Azobenzene-containing polymers offer tremendous advantages and opportunities over other stimuli-responsive materials to interface with biology. Azobenzene's fast, reversible, and innocuous cis–trans geometrical isomerization can be leveraged into dramatic intra- and inter-molecular changes when incorporated in polymeric materials. Azobenzene use has grown from a colorant, through to optical storage materials, and most recently in a variety of biologically themed applications. This review highlights the broad impact this photo-switch has had in recent years and offers a snapshot of the research landscape at the interface between photochemistry and biology. From photo-reversible micelles and peptides to controlled drug release and sensing, the versatility of azobenzene makes it a favored photo-switch found in many emerging applications. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Azobenzene-containing polymers offer a tremendous advantage and opportunity over other stimuli-responsive materials to interface with biology. Azobenzene's fast, reversible, and innocuous cis-trans geometrical isomerization when irradiated with light can be leveraged into dramatic intra-molecular and inter-molecular changes when intelligently designed in polymeric materials. From photo-reversible micelles and peptides, to controlled drug release and sensing, the versatility of azobenzene makes it a favored photo-switch to be found in many emerging applications.

A multifunctional ferrocene-modified poly(glycidyl methacrylate) (PGMA-Fc) and a difunctional β-cyclodextrin derivative (bis-CD) has been prepared for the construction of an electrically driven removable and self-healing polymeric materials based on the complexation reaction between ferrocene and β-CD groups. The chemical structures of PGMA-Fc and bis-CD have been characterized with Fourier transform infrared, ¹H nuclear magnetic resonance, and X-ray photoelectron spectroscopy. The effects of electrical voltages and medium conductivity on the decrosslinking efficiency of the crosslinked PGMA-Fc/CD polymer have been examined. The PGMA-Fc/CD network has shown removable feature and properties for application as a reworkable crosslinked material. Moreover, the crosslinked PGMA-Fc/CD sample has shown electrically driven self-healing behavior. The self-healing performance could be enhanced with wetting the sample to increase the electrical conductivity. As a result, the material could serve as a self-healing agent for commercial painting products. Preparation and application of a novel and efficient self-healing polymer have been demonstrated. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

The reversible complexation reaction of ferrocene and β-cyclodextrin has been applied for preparation of electrically-driven self-healing polymers. Addition of 20 wt % of this agent to a commercial product of car painting successfully brings the self-healing property to the coating product.

Polyesters constitute an important class of materials for in vivo biomedical applications. Poly(ɛ-caprolactone) (PCL) is a hydrophobic biodegradable polyester which is employed to a lesser extent in drug delivery applications due to its rather limited range of physicochemical characteristics. Here, we present a new paradigm for the synthesis of functionalized PCL via copolymerization of caprolactone with α,ω-epoxy esters. Ethyl 2-methyl-4-pentenoate oxide was used as a monomer which was copolymerized with ɛ-caprolactone to yield random copolymers of poly(ɛ-caprolactone-co-ethyl-2-methyl-4-pentenoate oxide). The reaction conditions were optimized to generate functionalization greater than 25%. The use of ester-epoxides favors a statistical and uniform distribution of monomer along the polymer backbone, which while preserving some of the key properties of PCL such as glass transition that is below room temperature, allows the tailoring of the melting behavior of PCL. The strategy presented herein opens up new avenues for engineering PCL properties for biomedical applications. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

In this work, a new paradigm to functionalize poly(ɛ-caprolactone) using α,ω-epoxy esters is demonstrated. The model α,ω-epoxy ester—ethyl 2-methyl-4-pentenoate oxide (EMPO) was synthesized via epoxidation and its incorporation into the PCL backbone via ring-opening copolymerization was investigated. Statistical, random copolymers of CL and EMPO were obtained and copolymerization parameters were determined to be 1.31 and 0.01, for ɛ-caprolactone and EMPO, respectively.

A reversible addition-fragmentation chain transfer (RAFT) agent was directly anchored onto superparamagnetic Fe₃O₄ nanoparticles (SPNPs) in a simple procedure using a ligand exchange reaction of 2-[(dodecylsulfanylcarbonylthiolsulfanyl) propionic acid] (DCPA) with oleic acid initially present on the surface of Fe₃O₄ nanoparticles. The DCPA-modified SPNPs were then used for the surface-mediated RAFT polymerization of di(ethylene glycol) ethyl ether acrylate and (oligoethylene glycol) methyl ether acrylate to fabricate structurally well-defined hybrid SPNPs with temperature-responsive poly[di(ethylene glycol) ethyl ether acrylate-co-(oligoethylene glycol) methyl ether acrylate] shell and magnetic Fe₃O₄ core. Evidence of a well-controlled surface-mediated RAFT polymerization was gained from a linear increase of number-average molecular weight with overall monomer conversions and relatively narrow polydispersity indices of the copolymers grown from the SPNPs. The resultant hybrid nanoparticles exhibited superparamagnetic property with a saturation magnetization of 55.1–19.4 emu/g and showed a temperature-responsive phenomenon as the temperature changed between 25 and 40 ^°C. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A Polym. Chem. 2013

Superparamagnetic and thermoresponsive hybrid nanoparticles composed of poly[di(ethylene glycol) ethyl ether acrylate-co-(oligoethylene glycol) methyl ether acrylate] shell and magnetic Fe₃O₄ core were synthesized via surface-mediated RAFT polymerization. The hybrid nanoparticles exhibited excellent magnetic susceptibility (M_s ≅ 55.1–19.4 emu/g) and showed a temperature-responsive behavior as the temperature changed between 25 and 40 ^°C.

Novel skipped-π polymers in which the π-components are connected with 2-substituted trimethylene tethering units exhibit bathochromically shifted, broadened ultraviolet absorption with a unique lower-energy absorption band and a largely red-shifted fluorescent emission. These results suggest that through-space π–π interactions owing to a stair-like stacking substructure in these polymers extend the π-conjugation of the components in the ground and excited states. As the photophysical properties of the polymers observed both in a solution and in a dried film are similar to those of the J-aggregates of π-molecules, these polymers may be considered as pseudo J-stacking (or J-like-stacking) polymers. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Novel skipped-π polymers comprising π-components connected with 2-substituted trimethylene tethering units that exist as stair-like stacking substructures were synthesized and found to exhibit bathochromically shifted, broadened UV absorption with a unique lower-energy absorption band and largely red-shifted fluorescent emission owing to the extended π-conjugation resulting from through-space π–π interactions in the ground and excited states.

Solvent-free nanofluids with surface functional groups composed of tetraalkylammonium ionic liquid organic salts and isothiocyanate decorating nanosilica cores are reported that exhibit viscous flow and glass transitions. These nanofluids when combined with hexamethylene diisocyanate and isophorone diisocyanate–polypropyleneglycol prepolymers are coated and autocured in humid air to produce thin films and clearcoats. These new resins are characterized thermally and by nanoindentation. Relative to the air-cured prepolymer control, low nanofluid loading (1–4% w/w) produces increased storage moduli and hardness and decreased loss factors. High loading (8 and 16%) results in softening with increased toughness. While the control exhibited marked viscoelastic recovery, this recovery was largely arrested in the nanocomposite coatings. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Solvent-free nanofluid and prepolymer are air cured to produce a tough and transparent clearcoat. The solvent-free nanofluid is prepared by surface modifying nanosilica (9–10 nm) with an ionic liquid type of organic salt and with reactive isothiocyanate. It is dissolved in a novel poly(propylene oxide) isophorone diisocyanate prepolymer, coated, and cured with atmospheric moisture at room temperature. The proportion of nanofluid (1-16%) tunes the moduli and produces nanocomposites harder (2×) to softer (½×) than the control.

This investigation reports the preparation and characterization of thermally amendable functional polymer bearing furfuryl functionality via reversible-addition fragmentation and chain transfer (RAFT) polymerization and Diels-Alder (DA) reaction. In this case, furfuryl methacrylate (FMA) was polymerized using 4-cyano-4-[(dodecylsulfanylthiocarbonyl)sulfanyl] pentanoic acid as RAFT reagent and 4,4′-azobis(4-cyanovaleric acid) as thermal initiator. ¹H NMR, ¹³C NMR, and matrix-assisted laser desorption ionization time-of-flight mass spectrometry analysis showed that furfuryl group in poly(furfuryl methacrylate) (PFMA) was not affected during RAFT polymerization and the tailor-made polymer had RAFT end group. The DA reaction was successfully carried out between the reactive furfuryl functionality of PFMA and different bismaleimides. The thermoreversible property of these DA polymers was characterized by FT-IR and DSC analysis. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Well-defined PFMA was successfully synthesized by reversible addition fragmentation chain-transfer (RAFT) polymerization technique using CDTSPA and 4 cyano-4-(thiobenzoylthio) pentanoic acid (CTBPA) as different chain transfer agents (CTA). Thereafter, reactive furfuryl group of PFMA was used to prepare crosslinked polymeric materials via DA reaction using different bismaleimides. These crosslinked polymers showed thermally amendable properties through DA and retro-DA click reaction only by applying temperature.

An efficient and novel one-pot process is developed to immobilize the atom transfer radical polymerization (ATRP) initiators onto the surface of fully pyrolyzed carbon hard spheres (CHSs) via a radical trapping process from the in situ thermal decomposition of bis(bromomethylbenzoyl)peroxide. The CHSs do not require any additional preparative treatment prior to the initiator immobilization. Styrene and methyl methacrylate are polymerized onto initiator-immobilized CHSs by surface-initiated atomic transfer radical polymerization (SI-ATRP). Samples are characterized using Fourier transform infrared, thermogravimetric analysis, scanning electron microscopy, and transmission electron microscopy. These methods of characterization confirmed that all the CHSs are coated with a uniform layer of grafted polymer. This efficient, one-pot immobilization of ATRP-initiators represents an exceptionally simple route for the rapid preparation of various polymer-coated carbon-based nanomaterials using SI-ATRP.

An atom transfer radical polymerization (ATRP) initiator has been chemically immobilized on the surface of carbon hard spheres (CHSs) in only one step by a radical trapping method. These initiator immobilized CHSs are used to graft polystyrene and poly(methyl methacrylate) chains via surface-initiated ATRP. The resultant grafted CHSs are covered by a dense uniform film of grafted polymers. The thickness of grafted polymer is controlled by tuning the amount of sacrificial free initiator during graft polymerization.

Poly(N-vinylcaprolactam) (PVCL) and poly(oligo(ethylene glycol) methyl ether methacrylate) (POEGMA) are well known for their thermoresponsive behavior in aqueous solutions. Indeed, they display lower critical solution temperatures (LCST) in the physiological range, which makes them interesting for biomedical devices and use in drug delivery systems. Homopolymers of N-vinylcaprolactam and di(ethylene glycol) methyl ether methacrylate as well as copolymers thereof were synthesized by solution and direct miniemulsion polymerizations. The cloud points of the copolymers in aqueous solution were investigated as a function of temperature, comonomer ratio, and in the presence of model pharmaceutical ingredients. By variation of the comonomer ratio, it was possible to control the cloud point temperature between 26 and 35 °C, which was found to be beneficial to attenuate the effect of the drugs that also altered the cloud points. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

N-Vinylcaprolactam and di(ethylene glycol) methyl ether methacrylate are copolymerized in high yield via miniemulsion polymerization. The lower critical solution temperature (LCST) of the obtained linear copolymers is controlled by their composition and the concentration of drugs in the solutions.

The microstructure of poly(1,3-pentadiene) synthesized by cationic polymerization of 1,3-pentadiene with ^tBuCl/TiCl₄ initiating system is analyzed using one-dimensional- and two-dimensional-NMR spectroscopy. It is shown that unsaturated part of chain contains only homo and mixed dyads with trans−1,4-, trans−1,2-, and cis−1,2-structures with regular and inverse (head-to-head or tail-to-tail) enchainment, whereas cis−1,4- and 3,4-units are totally absent. The new quantitative method for the calculation of content of different structural units in poly(1,3-pentadiene)s based on the comparison of methyl region of ¹³C NMR spectra of original and hydrogenated polymer is proposed. The signals of tert-butyl head and chloromethyl end groups are identified in a structure of poly(1,3-pentadiene) chain and the new approaches for the quantitative calculation of number-average functionality at the α- and ω-end are proposed. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Poly(1,3-pentadiene) synthesized by cationic polymerization of 1,3-pentadiene with ^tBuCl/TiCl₄ initiating system contains only homo and mixed dyads with trans−1,4-, trans−1,2-, and cis−1,2-structures with regular and inverse (head-to-head or tail-to-tail) enchainment, whereas cis−1,4- and 3,4-units are totally absent.

This article describes the synthesis of new cyclic compounds able to react with amines to get nonisocyanate polyurethanes (NIPUs). The contribution of the most studied five-membered cyclic carbonate was compared to five-membered cyclic dithiocarbonate analogous and to a six-membered cyclic carbonate. Difunctional reactive species were obtained by a simple substitution reaction or an efficient thiol–ene coupling reaction. The products, obtained with high yields, were characterized by 1H NMR, 13C NMR, and Fourier tansform infrared spectroscopy analysis. The dicyclocarbonates were then used to synthesize NIPUs by step growth polymerization with several diamines. These materials exhibited glass transition temperatures from 19 to −29 °C, molar mass from 1800 to 20,400 g mol⁻¹, and a 20% mass loss temperature (T_d = 20%) between 249 and 296 °C. Such materials are interesting candidates for coating applications. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Various bis(cyclic carbonates) were synthesized by thiol–ene coupling. Five- and six-membered cyclic carbonates and thiocarbonates were compared to yield nonisocyanate polyurethanes (PUs) with various amines. Synthesized PUs exhibit low T_g from −29 to 19 °C and high molar masses, interesting properties for coating applications.

The free radical reactivity ratios between styrene and different vinyl-1,2,3-triazole regioisomeric monomers in 1,4-dioxane at 65 °C have been established using nonlinear least square method. The results obtained for the reactivity ratio between regioisomers show exceptionally different polymerization behavior, highlighting the effects of the electronic and steric factors of these regioisomeric monomers. The experimental results highlight the effects of the electronic and sterics on the copolymerization behavior. In case of 1,4-vinyl-triazoles, it was found that without the steric effects, the reactivity is very similar to that of styrene and forms random copolymers. However, it was found that 1,5-vinyl-triazoles are more reactive than 1,4-vinyl triazoles. In the case of styrene-co-1,4-vinyl-1,2,3-triazoles, the reactivity ratios were calculated to be r_styrene: r_{1-octyl-4-vinyl-triazole} = 1.97:0.54, r_styrene : r_{1-benzyl-4-vinyl-triazole} = 1.62:0.50, and r_styrene: r_{1-methyl-4-vinyl-triazole} = 0.90:0.87. On the other hand, reactivity ratios for styrene-co-1,5-vinyl-1,2,3-triazoles were found to be r_styrene: r_{1-octyl-5-vinyl-triazole} = 0.13:0.66 and r_styrene: r_{1-benzyl-5-vinyl-triazole} = 0.34:0.49. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

This work investigates polymerization behavior of regioisomeric vinyl triazole monomers with styrene. The results obtained for the reactivity ratio between regioisomers show exceptionally different polymerization behavior highlighting the effects of the electronic and steric factors of these regioisomeric monomers. In the absence of any steric effects or electronic effects, a random copolymer is formed.

Novel thermo-responsive poly(N-isopropylacrylamide)-block-poly(l-lactide)-block-poly(N-isopropylacylamide) (PNIPAAm-b-PLLA-b-PNIPAAm) triblock copolymers were successfully prepared by atom transfer radical polymerization of NIPAAm with Br-PLLA-Br macroinitiator, using a CuCl/tris(2-dimethylaminoethyl) amine (Me₆TREN) complex as catalyst at 25 °C in a N,N-dimethylformamide/water mixture. The molecular weight of the copolymers ranges from 18,000 to 38,000 g mol⁻¹, and the dispersity from 1.10 to 1.28. Micelles are formed by self-assembly of copolymers in aqueous medium at room temperature, as evidenced by ¹H NMR, dynamic light scattering (DLS) and transmission electron microscopy (TEM). The critical micelle concentration determined by fluorescence spectroscopy ranges from 0.0077 to 0.016 mg mL⁻¹. ¹H NMR analysis in selective solvents confirmed the core-shell structure of micelles. The copolymers exhibit a lower critical solution temperature (LCST) between 32.1 and 32.8 °C. The micelles are spherical in shape with a mean diameter between 31.4 and 83.3 nm, as determined by TEM and DLS. When the temperature is raised above the LCST, micelle size increases at high copolymer concentrations due to aggregation. In contrast, at low copolymer concentrations, decrease of micelle size is observed due to collapse of PNIPAAm chains. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 00, 000–000

Novel thermo-responsive PNIPAAm-b-PLLA-b-PNIPAAm triblock copolymers were prepared by ATRP of NIPAAm with Br-PLLA-Br macroinitiator. Copolymers with excellent control over the molecular weight and narrow dispersity were obtained under mild condition. LCST was detected between 32.1 and 32.8 °C. Micelles are prepared by self-assembly of amphiphilic copolymers in aqueous medium. The micelles exhibit a thermo-responsive behavior, showing great potential as carrier of drugs.

Butyl rubber-poly(ethylene oxide) (PEO) graft copolymers with high PEO content (40–83 wt %) were synthesized by the functionalization and activation of the double bond moiety of butyl rubber containing high (7 mol %) isoprene content and subsequent reaction with PEO of different molecular weights from 750 to 5000 g/mol. The properties of these copolymers, along with other butyl rubber-PEO graft copolymers were studied in films and in aqueous solution. Despite the high PEO content, films of the copolymers were quite stable in water with respect to mass loss and were capable of releasing an encapsulated probe molecule in a manner that was dependent on the PEO content. At high PEO content they were resistant to the adhesion and growth of C2C12 cells. Despite the resistance of films to dissolution, it was possible to prepare nanosized aqueous assemblies via a THF-water exchange process and the sizes of the assemblies were tuned by their method of preparation. The assemblies were also able to encapsulate a probe molecule and were found to be nontoxic in vitro. Combined, this set of properties makes these new amphiphilic copolymers promising for a wide range of potential applications.

Butyl rubber-poly(ethylene oxide) (PEO) graft copolymers were synthesized through the derivatization of the isoprene moieties in butyl rubber containing high (7 mol %) isoprene content. Films of these graft copolymers exhibited interesting properties such as high stability in aqueous solution and resistance to the growth of cells at high PEO content. The copolymers also formed stable nanosized assemblies in aqueous solution and their size could be controlled through their preparation method.

We report the synthesis and characterization of a polythiophene block copolymer (P4) selectively functionalized with diaminopyrimidine moieties and a thymine tethered fullerene derivative (F1). Self-assembly between P4 and F1 through “three-point” complementary hydrogen bonding is studied by ¹H NMR spectroscopy and differential scanning calorimetry. A large Stern-Volmer constant (K_SV) of 1.2 × 10⁵ M⁻¹ is observed from fluorescence quenching experiments, revealing strong complexation between these two components. Solar cells employing P4 and F1 at different weight ratios as active layers are fabricated and tested; corresponding thin film morphologies are studied in detail by optical imaging and atomic force microscopy. Correlations between polymer complex structures, film morphologies, and device performance are discussed. Thermal stability of benchmark poly(3-hexylthiophene) bulk heterojunction solar cells is found to be improved by the addition of a few weight percent of P4/F1 complexes as compatibilizers. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 00, 000–000

A “rigid-rod bottle-brush” type conjugated copolymer–fullerene composite has been obtained through “three-point” complementary hydrogen bonding interactions between a selectively functionalized polythiophene block copolymer and a novel thymine tethered fullerene derivative. Such non-covalent interactions allow facile tuning of fullerene loading percentages and the relatively high binding strengths lead to solid-state morphology stabilization. Solar cells fabricated from such “rigid-rod bottle-brush” composite were studied in detail. Benchmark P3HT/PCBM BHJ device performance and thermal stability could be improved by adding a few percentage of such polymer/fullerene composite.

By CO₂ bubbling into an aqueous dimethyl sulfoxide solution, the polyamidine (Poly-Amd) prepared from hexamethylenediamine and triethyl orthoacetate was converted to the bicarbonate salt, Poly-AmdH·HCO₃, which formed aggregates. Conversely, the aggregates disappeared upon Ar bubbling to release the captured CO₂, reverting to Poly-Amd completely. Polyethyleneimine (PEI) also reversibly captured and released CO₂ molecules in solution by bubbling CO₂ and Ar, respectively, in an alternate manner. No appreciable difference was observed between Poly-Amd and PEI in CO₂ capture in solution. The binary system consisting of Poly-Amd and polyethylene glycol (PEG) captured CO₂ efficiently at ordinary pressure and reached a stationary state within 200 h, at which 66% of the amidine groups bound CO₂ molecules, which was released upon exposure to a N₂ flow. In contrast to the binary system with Poly-Amd, the binary system of PEI with PEG did not capture CO₂ efficiently, and only 5.7% of the amino groups bound CO₂ molecules after 600 h. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 00, 000–000

CO₂ capturing and releasing behavior of a linear polyamidine having a hexamethylene linker has been investigated in solution as well as in the solid state. The polyamidine captures and releases CO₂ in an aqueous solution to the same level as a common polyamine, polyethyleneimine. In contrast, a binary system consisting of the polyamidine and polyethylene glycol absorbs CO₂ much more efficiently than that with the polyethyleneimine and polyethylene glycol.

Electrochemical polymerization in crystal followed by polymerization in cholesteric liquid crystal allows production of crystal-liquid crystal ordered electro-optically active polymer. The polymer shows photonic insect like metallic reflection. The metallic color is tunable via electrochemical redox process.

Amino modified multiwall carbon nanotubes (MWNTs) are prepared, respectively, by two ways: the conventional one-step method that directly treats acyl chloride functionalized MWNTs with 4, 4′-diaminodiphenyl ether (ODA), giving the amino modified MWNT (Di-MWNT), as well as an improved two-step method in which acyl chloride functionalized MWNT react with mono-Boc protected ODA first and then the Boc-groups are deprotected to provide the amino modified MWNT (NH₂-MWNT). Anhydride-terminated polyimide (PI) composite films based on NH₂-MWNT and Di-MWNT are fabricated by solution blending and consequent planar casting. The exposed amino groups of NH₂-MWNT create strong covalent bonds with the anhydride-terminated polyamide acid in the course of N-acylation and curing chemical reactions. Solubility examinations of nanotubes and morphologies of the composite films indicate that the dispersion of NH₂-MWNT is significantly better than Di-MWNT in PI matrix and NH₂-MWNT can form connected network throughout the PI matrix which makes the NH₂-MWNT/PI film presenting superior conductivity. Both morphologies and mechanical properties of the composites show that NH₂-MWNT has stronger interfacial interaction with the PI matrix. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 00, 000–000

Amino functionalized multiwall carbon nanotubes (MWNTs) are obtained by two ways: conventional one-step method (Di-MWNT) and the improved two-step approach (NH₂-MWNT). Comparing with Di-MWNT, NH₂-MWNT shows more excellent dispersion and better compatibility in the polyimide (PI) matrix. NH₂-MWNTs can form connected network structure throughout the PI matrix, which makes the NH₂-MWNT/PI composite film having good conductivity, mechanical property, and thermal stability.

Vinylimidazole-based asymmetric ion pair comonomers (IPCs) which are free from nonpolymerizable counter ions have been synthesized, characterized and polymerized by free radical polymerization (FRP), atom transfer radical polymerization (ATRP), and reversible addition-fragmentation chain transfer (RAFT) mediated polymerizations in solution and by dispersion polymerization in water. The asymmetric nature of IPCs is due to the fact that cationic component of these IPCs is derived from vinylimidazole (VIm) and anionic component is derived from either styrenesulfonate (SS) or 2-acrylamido-2-methyl-1-propanesulfonate. Although under ATRP, conversions are either very low or negligible, FRP and RAFT produces polymers with high to moderate monomer conversions but with different solubility characteristics. This investigation provides insight to the polymerization behavior of each component of the asymmetric IPCs and also its effects on composition and solubility characteristics of the resulting polymers. The IPCs studied here are high temperature ionic liquid and thus the polymers synthesized from these IPCs are highly ionic in nature and possess very strong intermolecular interactions which makes some of these IPC based polymers completely insoluble in organic and aqueous solvents. This highly ionic interaction is exploited to synthesize ionically crosslinked PMMA. MMA on copolymerization with 5–6 mol % of IPC yielded copolymer which is insoluble in common organic solvents like THF, DMF, etc., unlike homo PMMA. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Three different vinylimidazole based asymmetric ion pair comonomers (IPCs) free from nonpolymerizable counter ions have been synthesized, characterized, and polymerized by different polymerization techniques including ATRP and RAFT. This investigation provides insight to the polymerization behavior of each individual component of these asymmetric IPCs and its effects on composition and solubility of polymer produced. The IPCs studied here are high temperature ionic liquids and the polymers synthesized from these IPCs are highly ionic in nature and possess very strong intermolecular interactions. This highly ionic interaction is exploited to synthesize ionically crosslinked PMMA.

Biohybrid nanogels are crosslinked colloidal networks that consist of biological and synthetic polymers as building blocks. Such polymer colloidal particles attracted much attention in recent years mainly due to their outstanding properties and huge application potential that by far overcome classical nanogels or microgels prepared from water-soluble synthetic polymers. In this report, we review recent developments on the synthesis and properties of biohybrid nanogels. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Biohybrid nanogels prepared synergistically by recapitulation of well-evolved biological mechanism with tailorable properties can be variedly used for different applications ranging from therapeutics to catalysis. Herein, we illustrate the recent developments in the fields of these biohybrids with elucidation of their potential application.

4′-Nonafluorobutylstyrene (3) was synthesized and polymerized by conventional and controlled radical polymerization (iodine transfer polymerization (ITP)). Such an aromatic fluoromonomer was prepared from Ullmann coupling between 1-iodoperfluorobutane and 4-bromoacetophenone followed by a reduction and a dehydration in 50% overall yield. Two radical polymerizations of (3) were initiated by AIBN either under conventional or controlled conditions, with 1-iodoperfluorohexane in 84% monomer conversion and in 50% yield. ITP of (3) featured a fast monomer conversion and a linear evolution of the ln([M]₀/[M]) versus time. The kinetics of radical homopolymerization of (3) enabled one to assess its square of the propagation rate to the termination rate (k_p²/k_t) in ITP conditions (36.2·10⁻² l·mol⁻²·sec⁻² at 80 °C) from the Tobolsky's kinetic law. Polydispersity index (Đ) of the fluoropolymer achieved by conventional polymerization was 1.30 while it worthed 1.15 when synthesized by ITP. Thermal stabilities of these oligomers were satisfactory (10% weight loss under air occurred from 305 °C) whereas the melting point was 47 °C. Contact angles and surface energies assessed from spin-coated poly(3) films obtained by conventional (hysteresis = 18°, surface energy 18 mN.m⁻¹) and ITP (hysteresis = 47°, surface energy 15 mN.m⁻¹) evidenced Đ values' influence onto surface properties of the synthesized polymers. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

4′-Nonafluorobutyl styrene (1) was synthesized and polymerized by conventional and controlled radical polymerizations namely iodine-transfer polymerization (ITP) technique in the presence of 1-iodoperfluorohexane. The kinetics of radical homopolymerization of (1) led to its k_p²/k_t value. Đ-values of these fluoropolymers were different (1.30 from conventional way and 1.15 from ITP). Thermal properties and surface energies of these homopolymers achieved for both techniques were discussed and evidenced the influence of Đ-values on their surface properties.

Crosslinking copolymerization of butyl methacrylate with a small amount of divinylbenzene (DVB) was carried out using single-electron transfer-living radical polymerization initiated with carbon tetrachloride (CCl₄) and catalyzed by Cu(0)/N-ligand in N,N-dimethylformamide to produce a highly oil-absorbing gel. The polymerization, gelation process, and oil-absorbing properties were studied in detail. Analysis of monomer conversion with reaction time showed that the polymerization followed first-order kinetics for both linear and crosslinking polymerization before gelation. Higher levels of DVB led to earlier gelation and the influence of N-ligand on gelation was also significant. Under optimal conditions, oil absorption of the prepared gel to chloroform could reach 42.1 g·g⁻¹. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Crosslinking copolymerization of butyl methacrylate with a small amount of divinylbenzene was carried out using single-electron transfer-living radical polymerization initiated with CCl₄ and catalyzed by Cu(0)/N-ligand in N,N-dimethylformamide to produce a highly oil-absorbing gel. The polymerization followed first-order kinetics for both linear and crosslinking polymerization before gelation. Under optimal conditions, oil absorption of the prepared gel to chloroform could reach 42.1 g·g⁻¹.

The first- and second-generation well-defined thermoresponsive amphiphilic linear–dendritic diblock copolymers based on hydrophilic linear poly(N-vinylcaprolactam) and hydrophobic dendritic aromatic polyamide have been synthesized via reversible addition fragmentation chain transfer polymerization of N-vinylcaprolactam by employing dendritic chain-transfer agents possessing a single dithiocarbamate moiety at the focal point. These linear–dendritic copolymers exhibit reversible temperature-dependent phase transition behaviors in aqueous solution as characterized by turbidity measurements using UV–vis spectroscopy. Their lower critical solution temperatures depend on the generation of the dendritic aromatic polyamides and the concentrations of the copolymer solutions. These amphiphilic copolymers are able to form nanospherical micelles in the aqueous solution as revealed by fluorescent spectroscopy, dynamic light scattering, and transmission electron microscope (TEM). The core–shell structure of micelles has been proved by ¹H NMR analyses of the micelles in D2O. The micelles loaded with indomethacin as a model drug showed high-drug loading capacity and thermoresponsive drug release behavior. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Thermoresponsive amphiphilic linear–dendritic block copolymers, composed of hydrophilic poly(N-vinylcaprolactam) chains and hydrophobic dendritic aromatic polyamide, have been designed and prepared by reversible addition fragmentation chain transfer polymerization. Their lower critical solution temperatures (LCSTs) depend on the generation of the dendrons and the concentrations of the copolymer solutions. They are capable of self-assembling into nanospherical micelles in water. A sustained drug release is achieved from the copolymer micelles, which is accelerated when the environmental temperature is raised slightly above the LCST.

The efficient Cu(0) wire-catalyzed single-electron transfer-living radical polymerization (SET-LRP) of oligo(ethylene oxide) methyl ether methacrylate (OEOMA) in DMSO and binary mixtures of DMSO with H₂O is reported. Addition of 10–80% H₂O to DMSO resulted in an increase in the apparent rate constant of propagation ( ), corresponding to an increase in the polarity and extent of disproportionation. At higher H₂O content, decreases, and in H₂O is slightly lower than that in DMSO. This unexpected behavior was attributed to the physical inaccessibility of Cu(0) wire catalyst to the hydrophobic reactive centers of OEOMA and initiator which self-assemble in H₂O into micellar aggregates and vesicles. This hypothesis was confirmed by the faster polymerization in H₂O than in DMSO during catalysis with Cu(0) nanoparticles generated by disproportionation of CuBr. SET-LRP of OEOMA can be performed in protic and dipolar aprotic solvents in air by the addition of hydrazine hydrate. The polymerization exhibited no induction period and identical as in the degassed experiment, and led to polymers with narrow molecular weigh distribution. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Efficient SET-LRP of oligo(ethylene oxide) methyl ether methacrylate (OEOMA) in DMSO, and binary mixtures of DMSO with H₂O in the absence and presence of air is reported. Both OEOMA and the initiator self-assemble in water into micellar aggregates and vesicles.

Terpolymers based on propylene with 1-pentene and 1-hexene as comonomeric units are satisfactorily synthesized using a metallocene catalyst. Thus, several terpolymers are prepared with distinct overall compositions in comonomers as well as three different 1-pentene/1-hexene ratios at a given composition to evaluate the influence on polymerization activity, intrinsic viscosity, and microstructural details. The new trigonal δ polymorph is observed in those quenched terpolymers with a global content in comonomers of about 14 mol %, independently of the ratio between both comonomers. However, preliminary results indicate a profound influence of that ratio on the crystallization rate. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Poly(propylene-co-1-pentene-co-1-hexene) terpolymers are synthesized and polymerization activity is evaluated as well as the molecular characteristics of the resulting materials. Moreover, the trigonal polymorph is developed in those terpolymers with the highest overall comonomers content independently of the ratio between both comonomers. Crystallization kinetics is, however, slowed down as 1-hexene concentration is increased.

(E)-1,3-pentadiene (EP) and (E)-2-methyl-1,3-pentadiene (2MP) were polymerized to cis-1,4 polymers with homogeneous and heterogeneous neodymium catalysts to examine the influence of the physical state of the catalyst on the polymerization stereoselectivity. Data on the polymerization of (E)-1,3-hexadiene (EH) are also reported. EP and EH gave cis-1,4 isotactic polymers both with the homogeneous and with the heterogeneous system, whereas 2MP gave an isotactic cis-1,4 polymer with the heterogeneous catalyst and a syndiotactic cis-1,4 polymer, never reported earlier, with the homogeneous one. For comparison, the results obtained with the soluble CpTiCl₃-based catalyst (Cp = cyclopentadienyl), which gives cis-1,4 isotactic poly(2MP), are examined. A tentative interpretation is given for the mechanism of the formation of the stereoregular polymers obtained and a complete NMR characterization of the cis-1,4-syndiotactic poly(2MP) is reported. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

(E)-2-methyl-1,3-pentadiene (2MP) was polymerized with heterogeneous and homogeneous neodymium catalysts, obtaining isotactic and syndiotactic cis-1,4 polymers, respectively. A tentative interpretation is given for the mechanism of the formation of these stereoregular polymers and a complete NMR characterization of the cis-1,4-syndiotactic poly(2MP) is reported.

Well-defined amphiphilic multiblock copolymers PDMAEMA-b-P(IBMD-co-PDO)-b-PEG-b-P(IBMD-co-PDO)-b-PDMAEMA [PDMAEMA-PIBMD-PPDO-PEG], based on poly(2-(dimethylamino)ethyl methacrylate) block (PDMAEMA), poly(3(S)-isobutyl-morpholine-2,5-dione-co-p-dioxanone) block (P(IBMD-co-PDO)), and poly(ethylene glycol) block (PEG) were successfully synthesized by combination of ring-opening polymerization (using 3(S)-isobutyl-morpholine-2,5-dione and p-dioxanone initiated by hydroxyl end of PEG) and atom transfer radical polymerization (ATRP). Furthermore, all these copolymers were characterized by ¹H NMR, ¹³C NMR, Fourier transformed-infrared, gel permeation chromatography, differential scanning calorimetry, and thermogravimetric analysis measurements. The degradation experiments showed that the molecular weight of PDMAEMA-PIBMD-PPDO-PEG decreased along with degradation time. In addition, these copolymers could readily self-assemble into nanosized microspheres in phosphate buffered solution. Ibuprofen (IBU) and doxorubicin (DOX) as a kind of combined model drugs were loaded into these microspheres by the combination of ionic interaction and hydrophobic effect. These copolymer microspheres exhibited high loading capacity (LC, up to 26.88%), encapsulation efficiency (EE, up to 61.29%), and sustained release behavior of IBU–DOX in phosphate buffered solution. The results of transmission electron microscopy and dynamic light scattering showed that the microspheres were well-defined uniform spherical particles with average diameter less than 120 nm. Therefore, it can be envisaged that these copolymer systems are promising candidates for controlled release application. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Well-defined amphiphilic multiblock copolymers PDMAEMA-b-P(IBMD-co-PDO)-b-PEG-b-P(IBMD-co-PDO)-b-PDMAEMA [PDMAEMA-PIBMD-PPDO-PEG], based on poly(2-(dimethylamino)ethyl methacrylate) block (PDMAEMA), poly(3(S)-isobutyl-morpholine-2,5-dione-co-p-dioxanone) block (P(IBMD-co-PDO)), and poly(ethylene glycol) block (PEG) were successfully synthesized by combination of ring-opening polymerization (ROP) (using 3(S)-isobutyl-morpholine-2,5-dione and p-dioxanone initiated by hydroxyl end of PEG) and atom transfer radical polymerization (ATRP). These multiblock copolymers PDMAEMA-PIBMD-PPDO-PEG could readily self-assemble into nanosized microspheres in PBS, combined model drugs ibuprofen (IBU) with doxorubicin (DOX) were loaded successfully into these microspheres, which exhibited high LC, EE, and drug release behavior in PBS. It can be envisaged that these copolymer systems are promising candidates for controlled release application.

Copper(0)-mediated controlled radical polymerization (CRP), or single-electron transfer-living radical polymerization (SET-LRP) is a robust and dynamic technique that has attracted considerable academic and industrial interest as a synthetic tool for novel value-added materials. Although SET-LRP possesses many advantages over other forms of CRP, this novel chemistry still requires concurrent engineering solutions for successful commercial application. In this highlight, the evolution of atom-transfer radical polymerization chemistry and development in continuous processes is presented, leading to recent research on the use of SET-LRP in continuous flow tubular reactors. The proofs of concept are reviewed, and remaining challenges and unexplored potential on the use of continuous flow processes with SET-LRP as a powerful platform for the synthesis of novel polymeric materials are discussed. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Copper-mediated controlled radical polymerization (CRP) has tremendous potential as a synthetic tool for value-added materials. Commercial viability of the technology hinges on decreasing production costs by reducing the concentration of copper metal used, and increasing production efficiency. In this highlight article, advancements in copper-mediated CRP chemistry and process development will be presented, with a particular focus on copper(0)-mediated CRP in continuous flow reactors as an environmentally friendly and economically viable platform for large-scale production of novel polymeric materials.

A set of three donor-acceptor conjugated (D-A) copolymers were designed and synthesized via Stille cross-coupling reactions with the aim of modulating the optical and electronic properties of a newly emerged naphtho[1,2-b:5,6-b′]dithiophene donor unit for polymer solar cell (PSCs) applications. The PTNDTT-BT, PTNDTT-BTz, and PTNDTT-DPP polymers incorporated naphtho[1,2-b:5,6-b′]dithiophene (NDT) as the donor and 2,2′-bithiazole (BTz), benzo[1,2,5]thiadiazole (BT), and pyrrolo[3,4-c]pyrrole-1,4(2H,5H)-dione (DPP), as the acceptor units. A number of experimental techniques such as differential scanning calorimetry, thermogravimetry, UV–vis absorption spectroscopy, cyclic voltammetry, X-ray diffraction, and atomic force microscopy were used to determine the thermal, optical, electrochemical, and morphological properties of the copolymers. By introducing acceptors of varying electron withdrawing strengths, the optical band gaps of these copolymers were effectively tuned between 1.58 and 1.9 eV and their HOMO and LUMO energy levels were varied between −5.14 to −5.26 eV and −3.13 to −3.5 eV, respectively. The spin-coated polymer thin film exhibited p-channel field-effect transistor properties with hole mobilities of 2.73 × 10⁻³ to 7.9 × 10⁻⁵ cm² V⁻¹ s⁻¹. Initial bulk-heterojunction PSCs fabricated using the copolymers as electron donor materials and [6,6]-phenyl C71 butyric acid methyl ester (PC₇₁BM) as the acceptor resulted in power conversion efficiencies in the range of 0.67–1.67%. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

New naphtho[1,2-b:5,6-b′]dithiophene-containing donor-acceptor conjugated copolymers have been designed and developed for application in polymer solar cells. The effect of different electron-acceptor groups on the optoelectronics and photovoltaic properties of the copolymers have been evaluated and described.

Microgels based on thermally responsive polymers have been widely investigated in the context of controlled release applications, with increasing recent interest on developing a clearer understanding of what physical, chemical, and biological parameters must be considered to rationally design a microgel to deliver a specific drug at a specific rate in a specific physiological context. In this contribution, we outline these key design parameters associated with engineering responsive microgels for drug delivery and discuss several recent examples of how these principles have been applied to the synthesis of microgels or microgel-based composites. Overall, we suggest that in vivo assessment of these materials is essential to bridge the existing gap between the fascinating properties observed in the lab and the practical use of microgels in the clinic. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Thermally responsive microgels have been widely investigated in the context of controlled release applications. In this feature article, we outline key design parameters associated with engineering responsive microgels for drug delivery and discuss several recent examples to illustrate how these principles have been applied to the synthesis of microgels or microgel-based composites. The existing gap between the fascinating properties observed in the lab and the practical use of microgels in the clinic needs to be bridged.

Thermally responsive poly (N-isopropylacrylamide) (pNIPAm)-based hydrogel particles (microgels) have been extensively studied over past few decades. We, and others, have found that assemblies of these microgels exhibit unique properties that make them useful such as nonfouling surface coatings, drug release/delivery vehicles, and sensors. In this submission, we review our efforts to develop novel water remediation systems and optical devices from pNIPAm-based microgels. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

The use of poly (N-isopropylacrylamide) (pNIPAm)-based microgels for water remediation and sensing/biosensing is highlighted. For water remediation, the microgels are used as a sorbent, which are capable of removing organic molecules from water. Sensing applications rely of the fabrication of pNIPAm microgel-based devices, which exhibit visual color. We show that the color of the devices depends on solution temperature, pH, and glucose concentration. This highlight also details our fundamental studies of these color tunable materials.

Polyprolines are attractive polymers because of their folding property into polyproline II (PPII) structure, their significance in protein/protein interactions, and their potential as new therapeutic targets. Silaproline (Sip) is an analogue of proline, which exhibits similar conformational properties. The presence of dimethylsilyl group confers to Sip a higher lipophilicity as well as an improved resistance to biodegradation. Enantiomerically pure Sip was available in gram quantities from resolution of the enantiomers by chiral high performance liquid chromatography. This study describes the first synthesis of Sip N-carboxyanhydride (NCA) and shows preliminary results on comparison of polymerization of (l)Pro-NCA and (d)Sip-NCA to obtain homopolypeptides with PPII structure, polyproline, and polysilaproline polymers. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Reported here are the synthesis and characterization of new homopolypeptides with PPII structure. These biopolymers were obtained by ring-opening polymerization of silaproline (silylated analogue of proline) N-carboxyanhydride. Homopolysilaprolines were characterized by NMR, MALDI-Tof and circular dichroism.

Dispersion RAFT polymerization of styrene in the alcohol/water mixture mediated with the brush macro-RAFT agent of poly[poly(ethylene oxide) methyl ether vinylphenyl-co-styrene] trithiocarbonate [P(mPEGV-co-St)-TTC] with similar molecular weight but different chemical composition is investigated. Well-controlled RAFT polymerization including an initial slow homogeneous polymerization and a subsequent fast heterogeneous polymerization at almost complete monomer conversion is achieved. The molecular weight of the synthesized block copolymer increases linearly with the monomer conversion, and the polydispersity is relatively narrow (PDI < 1.3). The RAFT polymerization kinetics is dependent on the chemical composition in the brush macro-RAFT agents, and those with high content of hydrophobic segment lead to fast RAFT polymerization. The growth of the block copolymer nano-objects during the RAFT polymerization is explored, and various block copolymer nano-objects such as nanospheres, worms, vesicles and large-compound-micelle-like particles are prepared. The parameters such as the chemical composition in the brush macro-RAFT agent, the chain length of the solvatophobic block, the concentration of the feeding monomer and the solvent character affecting the size and morphology of the block copolymer nano-objects are investigated. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Well-controlled dispersion RAFT polymerization of styrene in the alcohol/water mixture mediated with the brush macro-RAFT agent of poly[poly(ethylene oxide) methyl ether vinylphenyl-co-styrene] trithiocarbonate is performed and various block copolymer nano-objects such as nanospheres, worms, vesicles, and large-compound-micelle-like particles are prepared.

The synthetic polycations are ideal candidates as antimicrobial agents, because they resemble natural antimicrobial peptides, but to render hemocompatibility to these materials is a great challenge. Herein, we used 2-(tert-butyl-aminoethyl) methacrylate (TBAEMA), to synthesize its homopolymer and pegylated random and diblock copolymers with polyethyleneglycol methacrylate (PEGMA, M_n = 360 Da) by single-electron transfer–living radical polymerization (SET-LRP). In the second step, the secondary amino groups in the precursor polymers were quaternized with iodomethane and bromohexane, to obtain three series of quaternized polymers. The antimicrobial properties of these quaternized polymers were evaluated against Escherichia coli (E. coli), by studying the minimum inhibitory concentrations (MICs) which ranged between 32 and 200 mg L⁻¹ and showed higher values for the quaternized random than the diblock copolymers. In addition to, we have also demonstrated the grafting of these polycations onto polycarbonate urethane film surfaces, which showed good killing efficacy against E. coli. Furthermore, the hemolysis of these materials was investigated against human red blood cells, which indicated that except the quaternized homopolymers that showed highest hemolysis, all other amphiphilic polycations exhibited very low hemolytic activity. Therefore, our designed materials with controlled structures and functionality, synthesized from cheaply available resources could serve as useful agents in the field of biomedicines and implantable materials. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

The controlled design of three series of antibacterial amphiphilic polycations such as PTBAEMA, PTBAEMA-b-PEGMA, and PTBAEMA-co-PEGMA were carried out by SET-LRP. Their antibacterial properties were evaluated against E. coli and expressed as MICs, while for the PCU- modified film surfaces, depicted as percent killing. Upon interaction with bacterial cells, these polycations mimic AMPs and causes disruption of cytoplasmic membranes. The biocompatibility against mammalian RBCs indicated that PEGMA protect mammalian cell membranes from severe action, and also because of lesser number of cationic charges on its surface. Therefore, these materials can serve as useful candidates in future as pharmaceuticals.

Stimuli-responsive star polymers gain more and more interest over the last decades due to their unique properties compared to their linear counterparts. The branched structure for instance has influence on the responsive behavior of these polymers. This review offers an overview of stimuli-responsive star polymers generated by different polymerization techniques, e.g. anionic and controlled radical polymerization (CRP). Beside conventional branched homopolymers different other types like block copolymers, miktoarm star copolymers, core crosslinked star polymers (CCS) and comb polymers are also presented. Furthermore their responsive behavior in solution or immobilized on a substrate, and their applications are outlined. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Stimuli-responsive star polymers with various numbers of arms and compositions can be generated by different polymerization techniques, that is, anionic and controlled radical polymerization (CRP). Their stimuli-responsive behavior in solution or immobilized on a substrate as well as their potential application are reviewed.

Amphiphilic diblock copolymers with various block compositions were synthesized on poly(2-ethyl-2-oxazoline) (PEtOz) as a hydrophilic block and poly(4-methyl-ε-caprolactone) (PMCL) or poly(4-phenyl-ε-caprolactone) (PBCL) as a hydrophobic block. These PEtOz-b-PMCL and PEtOz-b-PBCL copolymers consisting of soft domains of amorphous PEtOz and PM(B)CL had no melting endothermal peaks but displayed T_g. The lower critical solution temperature (LCST) values for the PEtOz-b-PMCL, and the PEtOz-b-PBCL aqueous solution were observed to shift to lower temperature than PEtOz homopolymers. Their aqueous solutions were characterized using fluorescence techniques and dynamic light scattering (DLS). The block copolymers formed micelles with critical micelle concentrations (CMCs) in the range 0.6–11.1 mg L⁻¹ in an aqueous phase. As the length of the hydrophobic PMCL or PBCL blocks elongated, lower CMC values were generated. The mean diameters of the micelles were between 127 and 318 nm, with PDI in the range of 0.06–0.21, suggesting nearly monodisperse size distributions. The drug entrapment efficiency and drug-loading content of micelles depend on block polymer compositions. In vitro cell viability assay showed that PEtOz-b-PMCL has low cytotoxicity. Doxorubicin hydrochloride (DOX)-loaded micelles facilitated human cervical cancer (HeLa) cell uptake of DOX; uptake was completed within 2 h, and DOX was able to reach intracellular compartments and enter the nuclei by endocytosis. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Amphiphilic PEtOz-b-PMCL and PEtOz-b-PBCL showed low cytotoxicity. DOX-loaded micelles facilitated HeLa cell uptake of DOX, and DOX was able to reach intracellular compartments and enter the nuclei by endocytosis. PEtOz-b-PM(B)CL can be used as the drug delivery.

Based on 2, 5-bis[(4-alkoxyphenyl)oxycarbonyl]styrenes (M-OCm, m is the number of the carbons of alkyl tails, m = 1, 4, and 18), three series of binary copolymers with high-molecular weights, {poly(M-OC1-co-M-OC4), poly(M-OC1-co-M-OC18), and poly(M-OC4-co-M-OC18)} have been prepared via free-radical polymerization. The random nature of the copolymers was expected on the basis of the assumed similar reactivities because of the analogous monomers. The phase behaviors of copolymers were studied by DSC, POM, and one-dimensional wide-angle X-ray diffraction. The results showed that liquid crystalline (LC) phase structures of copolymers, containing smectic phase, reentrant isotropic phase, columnar phase. and isotropic phase, were strongly depended on the composition and the alkyl length due to the competing among the steric effect, the microphase separation and the driving force of the entropy. When one of them occupied a dominant position, the LC phase structure can be presented for the copolymers. Otherwise, the LC phase structure is lost despite the pair of corresponding homopolymers forming mesogenic structure. Therefore, through copolymerization, LC behavior of the mesogen-jacketed liquid crystalline polymers can be greatly varied. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Three series of binary copolymers with high-molecular weights have been prepared via free-radical polymerization based on 2, 5-bis[(4-alkoxyphenyl)oxycarbonyl]styrenes (M-OCm, m is the number of the carbons of alkyl tails, m = 1, 4, and 18). The phase behaviors of copolymers were studied by DSC, POM, and 1D WAXD. The experiment results showed that the self-assemble behavior of mesogen-jacketed liquid crystalline copolymers was strongly depended on the composition and the alkyl length due to the competing among the steric effect, the microphase separation, and the driving force of the entropy.

Microgels can switch their chemical/physical properties with external stimulus, and the colloidal behavior of microgels is strongly affected by interparticle interactions. In this article, we introduce smart microgels, focusing on Janus microgels and oscillating microgels developed by our group. Janus microgels show anisotropic shape and chemical/physical properties, and thus the structures of their flocs are also anisotropic. Oscillating microgels show autonomous swelling/deswelling and dispersing/flocculating oscillations through synchronization with chemical reactions. The interparticle interactions of these microgels are discussed. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Microgels can switch their chemical and physical properties on external stimulus, and the colloidal behavior of microgels is strongly affected by interparticle interactions between them. In this paperarticle, we introduce Janus microgels and oscillating microgels developed by our group. In particular, the interparticle interactions of these microgels are discussed.

Diblock and triblock dendron–polymer conjugates containing biodegradable polyester dendron blocks and polyethylene glycol (PEG) polymer were synthesized using the Diels–Alder “click” cycloaddition reaction. PEG polymers with furan-protected maleimide functionality were synthesized and reacted with biodegradable polyester dendrons containing an anthracene moiety at their focal point. First through third generations of biodegradable polyester dendrons containing an anthracene unit at their focal point were synthesized using a divergent strategy. Efficient conjugation of the dendrons to polymers was demonstrated using ¹HNMR and size exclusion chromatography. This modular approach provides an easy access to the design of multivalent PEG conjugates. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Dendron-–polymer conjugates derived from water -soluble and biocompatible polyethylene glycol polymers and biodegradable polyester dendrons were synthesized using the Diels-–Alder ‘“click'” chemistry. Furan -protected- maleimide containing end-functionalized polyethylene glycol (PEG) polymers were reacted with polyester dendrons containing an anthracene group at focal point. The method provides facile preparation of multivalent PEG polymers amenable to further functionalization.

The living free radical polymerizations of vinyl acetate (VAc) were successfully achieved in the presence of a novel organic selenium compound (diselenocarbonates), with 2,2′-azobisisobutyronitrile (AIBN) as the initiator. The living characteristics of the VAc polymerization were confirmed by the linear first-order kinetic plots and linear increase of molecular weights (M_n) of the polymers with monomer conversions, while keeping the relatively low molecular weight distributions. In addition, the end of the polymers contains selenium element which may be useful in biotechnological and biomedical applications. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

A novel organic selenium compound (diselenocarbonates) was successfully used as RAFT agent for the polymerization of VAc, which provide the way for the incorporation of selenium into polymer under the controlled manner.

To synthesize the novel molecular- and pH-stimulus-responsive hydrogel, we prepared poly(ethylene glycol)-based hydrogel containing ionic groups. We evaluated the fundamental swelling/shrinking properties of the hydrogels synthesized by various conditions. Decreasing the molecular weight of a crosslinker provided the increasing of the equilibrium swelling ratio. Also, the equilibrium swelling ratio was changed by the introduction of functional ionic monomers and its compositions. Furthermore, the swelling/shrinking behaviors of the hydrogels were affected by the environmental condition of aqueous solution, in fact the hydrogels were considerably shrunk (to one-fifth volume) using a di-ionic solute in the aqueous solution through the ionic interactions between the hydrogel and the solutes. Additionally, the specific shrinking to diamine compounds was also observed in response to pH change. These results clearly show the swelling/shrinking responsibility of the hydrogels toward the molecular recognitions and its pH conditions. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Polyethylene glycol (PEG)-based hydrogels exhibit that the equilibrium swelling ratios are changed by varying the length of PEG chains of PEG dimethacrylate, functional monomer, porogenic solvents, and its compositions. Furthermore, the swelling/shrinking behaviors of PEG-based hydrogels were affected by the environmental condition of aqueous solution, in fact the hydrogels were greatly shrunk (to one-fifth volume) using a di-ionic solute through the ionic interaction toward ionic groups in hydrogels. In addition, the specific shrinking behavior to diamine compounds was also observed in response to pH change. In other words, the hydrogels are responsively swelling/shrinking toward pH and molecular recognitions.

Microgels are crosslinked soft particles with a three-dimensional network structure that are swollen in a good solvent. They have frequently been termed “smart materials” since the size, softness, and interaction forces between particles are tunable by external stimuli such as temperature, pH, or magnetic and electric fields. It is this unique feature that has captured the interest of many scientists across a wide range of disciplines. This brief review covers the basic aspects of the relationships between the network structure and gel properties of the thermally sensitive poly(N-isopropylacrylamide) (pNIPAM) microgels including the phase transition process, the internal structure of microgels, and the phase behavior. Additionally, we highlight the impacts of microgels on the biomedical applications, especially in the gene delivery, cell matrix and differentiation of stem cells. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Microgels are crosslinked soft particles with a three-dimensional network structure that are swollen in a good solvent. Among them, pNIPAM based microgel received great attention due to their unique thermal transition property. Especially, the tunable property and excellent biocompatibility make pNIPAM microgels desirable in biomedical field. The roles of microgels, such as drug delivery vector or cell matrix is highly correlated with their physical properties, including the core-shell structure, the swollen to shrunk transition and so on.

Candidate materials for low-loss optical waveguides based on poly(glycidyl methacrylate-ran-pentafluostyrene) [P(GMA-ran-PFS)] copolymers were synthesized by nitroxide mediated polymerization (NMP) initiated with BlocBuilder^® [N-(2-methylpropyl)-N-(1-diethlphosphono-2,2-dimethylpropyl)-O-(2-carboxylprop-2-yl) hydroxylamine] bearing a succinimidyl ester group (NHS-BlocBuilder) at 90 °C in 1,4 dioxane. The copolymerizations yielded copolymers with low dispersity M¯_w/M¯_n between 1.2 and 1.4. The core structure of single-mode channel waveguides was fabricated by direct UV lithographic patterning. The copolymers with low M¯_w/M¯_n resulted in line width roughness (LWR) of about 0.16 μm, whereas LWR of copolymers with M¯_w/M¯_n=3.5 but similar compositions was about 0.5 μm. The improvement in microstructural control allotted by NMP permitted finer pattern replication for copolymers desired for optical waveguides, as suggested for photoresist polymers. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Photocrosslinkable optical waveguides consisting of well-defined GMA/PFS random copolymers synthesized by NMP are fabricated in this study. As features ∼1 μm were approached, lower polymer dispersity (M¯_w/M¯_n) afforded by NMP reduced the line edge roughness (LWR).

An array of highly fluorinated polymerizable phosphonium salts (HFPPS) were synthesized from PH₃ and utilized in UV-curable formulations. Inclusion of these salts at very low loading (0.1–1 wt %) into hexanediol diacrylate (HDDA) resulted in hydrophobic surfaces. The water repellency was achieved with short C₄F₉ fluorocarbon appendages in the monomer as opposed to the bioaccumulative C₈F₁₇ appended polymers. The physical properties of these new monomers were also characterized. The molecular architecture of the monomers had a pronounced effect on both their physical properties along with the degree of hydrophobicity imparted in the polymer. Salts utilizing the bis(trifluoromethylsulfonyl)imide anion displayed excellent compatibility with HDDA, while the chloride salts were insoluble. Time-of-flight secondary ion mass spectrometry (TOF-SIMS) confirmed the presence of the HFPPS at the surface of the polymer coating. For the first time this demonstrates how these salts may be used to functionalize the surface of a UV-cured film with ionic species. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Highly fluorinated phosphonium salts bearing a polymerizable group were synthesized and incorporated into photopolymerizable systems. This imparted hydrophobic behaviour to the cured films despite the presence of ionic charges. A structure-activity relationship was found between the structure and architecture of the phosphonium core and its hydrophobic performance. TOF-SIMS analysis confirmed the presence of the fluorinated species at the polymer/air interface.

Precision synthesis of polymers has been a hot topic in recent years. While this is notoriously difficult to address for polymers with a CC backbone, Merrifield has discovered a way many decades ago for polypeptides. Using a similar approach, N-substituted polypeptides, so-called polypeptoids have been synthesized and studied for about 20 years. In contrast, the living ring-opening polymerization (ROP) of N-substituted N-carboxyanhydrides was among the first living polymerizations to be discovered. More recently, a surge in new synthetic approaches led to the efficient synthesis of cyclic or linear multiblock copolypeptoids. Thus, polypeptoids can be synthesized either by solid phase synthesis to yield complex and exactly defined oligo- and small polymers or by ROP of appropriately N-substituted N-carboxyanhydrides (NNCA) to give linear, cyclic, or star-like polymers. Together with an excellent biocompatibility, this polymer family may have a bright future ahead as biomaterials. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Polypeptides are nature's precision polymers that exhibit sequence specific functions such as catalysis and molecular recognition. Other properties such as secondary structure formation or smart responses to external triggers do require defined but not sequence specific polymers. Polypeptoids have been shown to be able to address these issues. A comprehensive overview on the different synthetic routes towards molecularly defined polypeptoids and polypeptoids with narrow dispersities as well as on their properties is given.

Four novel helical poly(phenylacetylene)s with amino-functionalized cinchona alkaloid pendant groups connecting to the phenyl rings through a sulfonamide linkage were synthesized by the polymerization of the corresponding phenylacetylene monomers using Rh⁺(2,5-norbornadiene)[(η⁶-C₆H₅)B⁻(C₆H₅)₃] (Rh(nbd)BPh₄) as the catalyst. The optically active sulfonamide-linked polymers adopted a helical conformation with an excess of one-handedness as supported by the appearance of the induced Cotton effects in the main-chain chromophore regions, and efficiently catalyzed the enantioselective methanolytic desymmetrization of a cyclic anhydride and aza-Michael addition of aniline to chalcone, thereby producing the corresponding optically active products up to 86% enantiomeric excess. However, their enantioselectivities from the methanolytic desymmetrization were slightly lower than those catalyzed by the corresponding cinchona alkaloid-bound monomers. On the other hand, during the asymmetric aza-Michael addition, a unique enhancement of the enantioselectivity was observed for several sulfonamide-linked helical polymers, and thus affording a remarkably higher enantioselectivity compared to those of the corresponding monomers and nonhelical polymers bearing the identical cinchona alkaloid residues. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Novel helical poly(phenylacetylene)s with amino-functionalized cinchona alkaloid pendant groups connecting to the phenyl rings through a sulfonamide linkage were synthesized. The optically active sulfonamide-linked polymers adopted a helical conformation with an excess of one-handedness, and efficiently catalyzed the enantioselective aza-Michael addition of aniline to chalcone, and thus affording a remarkably higher enantioselectivity (up to 86% ee) than those of the corresponding monomers and nonhelical polymers.

A series of novel cyclic olefin copolymers (COCs), including ethylene/tricyclo[4.3.0.1^2,5]deca-3-ene (TDE), ethylene/tricyclo[4.4.0.1^2,5]undec-3-ene (TUE), and ethylene/tricyclo[6.4.0.1^9,12]tridec-10-ene (TTE) copolymers, have been synthesized via effective copolymerizations of ethylene with bulk cyclic olefin comonomers using bis(β-enaminoketonato) titanium catalysts (1a [PhNC(CH₃)CHC(CF₃)O]₂TiCl₂; 1b: [PhNC(CF₃)CHC(Ph)O]₂TiCl₂). With modified methylaluminoxane as a cocatalyst, both catalysts exhibit high catalytic activities, producing high molecular weight copolymers with high comonomer incorporations and unimodal molecular weight distributions. The microstructures of obtained ethylene/COCs are established by combination of ¹H, ¹³C NMR, ¹³C DEPT, HSQC ¹H¹³C, and ¹H¹H COSY NMR spectra. DSC analyses indicate that the glass transition temperature (T_g) increases with the enhancement of comonomer volume (TDE < TUE < TTE). High T_g value up to 180 °C is easily attained in ethylene/TTE copolymer with the low content of 35.8 mol %. TGA analyses reveal that these copolymers all possess high thermal stability with degradation temperatures (T_d) higher than 370 °C in N₂ and air. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 00, 000–000

Novel cyclic olefin copolymers (COCs) with high glass transition temperature and high thermal stability have been successfully obtained in this work via effective copolymerization of ethylene and bulky cyclic olefin.

In this article, the synthesis of a series of conjugated rod–rod block copolymers based on poly(3-hexylthiophene) (P3HT) and poly(phenyl isocyanide) (PPI) building blocks in a single pot is presented. Ni-catalyzed Grignard metathesis polymerization of 2,5-dibromo-3-hexylthiophene and subsequent addition of 4-isocyanobenzoyl-2-aminoisobutyric acid decyl ester in the presence of Ni(dppp)Cl₂ as a single catalyst afford P3HT-b-PPI with tunable molecular weights and compositions. In solid state, microphase separation occurred as differential scanning calorimetric analysis of P3HT-b-PPI revealed two glass transition temperatures. In solutions, the copolymers can self-assemble into spherical aggregates with P3HT core and PPI shell in tetrahydrofuran and exhibit amorphous state in CHCl₃. However, atomic force microscopy revealed that the block copolymers self-assemble into nanofibrils on the substrate. These unique features warrant the resultant conjugated rod–rod copolymers' potential study in organic photovoltaic and other electronic devices. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 00, 000–000

A series of molecular weights and compositions tunable conjugated rod–rod block copolymers, P3HT-b-PPI, has been synthesized in the presence of Ni(dppp)Cl₂ as a single catalyst in one pot. Spherical aggregates and amorphous state were observed in tetrahydrofuran and CHCl₃ solutions, respectively. Atomic force microscopy revealed that the block copolymers could self-assemble into nanofibrils from CHCl₃ on the substrate. The unique features warrant the resultant copolymers' potential study in organic photovoltaic and other electronic devices.

A series of electroactive polyetherimides (PEIs) with triphenylamine (TPA) units were prepared from the polycondensation reactions of 4,4′-bis(p-aminophenoxy)triphenylamine with aromatic tetracarboxylic dianhydrides via a conventional two-step technique. The PEIs showed high thermal stability, with glass-transition temperatures of 234–282 °C and decomposition temperatures in excess of 500 °C. They showed well-defined and reversible redox couples during both p- and n-doping processes, together with multielectrochromic behaviors. These polymers exhibited enhanced redox-stability and electrochromic performance as compared with the corresponding analogs without the phenoxy spacer between the TPA and imide units. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 00, 000–000

A series of electroactive polyetherimides (PEIs) were synthesized from 4,4′'-bis(p-aminophenoxy)triphenylamine and various aromatic dianhydrides. Insertion of a phenoxy spacer between the triphenylamine unit and the imide ring decreases the oxidation potentials and increases the electrochemical stability of the polyimides. All the PEIspolyetherimides exhibit an ambipolar electrochemical and electrochromic behavior. The PEIpolyetherimide films exhibit reversible electrochemical oxidation accompanied by strong color changes that can be switched through modulation of the applied potential.

Two phenazine donor–acceptor-conjugated copolymers (P1 and P2) with the same polymer backbone but different anchoring positions of alkoxy chain on the phenazine unit were investigated to identify the effect of changing the position of alkoxy chains on their optical, electrochemical, blend film morphology, and photovoltaic properties. Although the optical absorption and frontier orbital energy levels were insensitive to the position of alkoxy chains, the film morphologies and photovoltaic performances changed significantly. P1/PC₇₁BM blend film showed the formation of phase separation with large coarse aggregates, whereas P2/PC₇₁BM blend film was homogeneous and smooth. Accordingly, power conversion efficiency (PCE) of photovoltaic devices increased from 1.50% for P1 to 2.54% for P2. In addition, the PCE of the polymer solar cell based on P2/PC₇₁BM blend film could be further improved to 3.49% by using solvent vapor annealing treatment. These results clearly revealed that tuning the side-chain position could be an effective way to adjust the morphology of the active layer and the efficiency of the photovoltaic device. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 00, 000–000

Two phenazine-based donor–acceptor copolymers (P1 and P2) were synthesized. Although the effects of the position of alkoxy groups attached to the phenazine unit on optical and electrochemical properties of copolymers were limited, very different copolymer/PC₇₁BM blend morphologies and photovoltaic performance were observed.

A series of side-chain liquid-crystal polymers, poly[6-[4-(4′-n-alkyl benzoateazo)phenoxy]-hexylmethacrylate]s (PMAzoCOOR_m, m = 1, 2, 3, 4, 5, 6, 8, 10, 14, and 18) have been prepared by two synthetic methods. The chemical structure of the monomers was confirmed by ¹H NMR and mass spectrometry. The molecular characterizations of the polymers were performed with ¹H NMR and gel permeation chromatograph. The phase behaviors of polymers were investigated by the combination of techniques including differential scanning calorimetry, polarized optical microscopy, and small-angle X-ray scattering. For m = 1, 2, 3, 4, 5, and 6, the polymers exhibited a monosmectic A phase in which the smectic layer period was almost identical to the side-chain length. In addition, for m = 2, 3, 4, and 5, they presented the monosmectic C phase in low temperature; moreover, the tilt angle increased from 23.3 to 40.5°. For m = 8, 10, 14, and 18, the polymers showed a bilayer smectic A phase in which the layer spacing was larger than a fully extended side chain but less than two extended chains. On the other hand, for the clearing point, with the increasing of m, it first decreased, and then increased. All of these indicated that the length of alkyl tails played an important role in the phase behaviors of these polymers. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 00, 000–000

A series of side chain liquid -crystal polymers, the poly [6-[4-(4′′-n-alkyl benzoateazo)phenoxy]-hexylmethacrylate]s (PMazoCOOR_m, m is the number of the carbons of alkyl tails, m = 1, 2, 3, 4, 5, 6, 8, 10, 14, and 18) have been prepared by two synthetic methods. The phase behaviors of the polymers have been investigated by a combination of techniques including differential scanning calorimetry, polarized optical microscopy, and 1D small-angle X-ray scattering. The results of the experiments results indicated that the length of alkyl tails played an important role in the phase behaviors of these polymers.

In this study, the poly(N-isopropylacrylamide-methylacrylate acid)/Fe₃O₄/poly(N-isopropylacrylamide-methylacrylate acid) (poly(NIPAAm-MAA)/Fe₃O₄/poly(NIPAAm-MAA)) two-shell magnetic composite hollow latex particles were synthesized by four steps. The poly(methyl methacrylate-co-methylacrylate acid) (poly(MMA-MAA)) copolymer latex particles were synthesized first. Then, the second step was to polymerize NIPAAm, MAA, and crosslinking agent in the presence of poly(MMA-MAA) latex particles to form the linear poly(MMA-MAA)/crosslinking poly(NIPAAm-MAA) core–shell latex particles. Then, the core–shell latex particles were heated in the presence of NH₄OH to dissolve the linear poly(MMA-MAA) core to form the poly(NIPAAm-MAA) hollow latex particles. In the third step, the Fe₃O₄ nanoparticles were generated in the presence of poly(NIPAAm-MAA) hollow polymer latex particles and formed the poly(NIPAAm-MAA)/Fe₃O₄ magnetic composite hollow latex particles. The fourth step was to synthesize poly(NIPAAm-MAA) in the presence of poly(NIPAAm-MAA)/Fe₃O₄ latex particles to form the poly(NIPAAm-MAA)/Fe₃O₄/poly(NIPAAm-MAA) two-shell magnetic composite hollow latex particles. The effect of various variables such as reactant concentration, monomer ratio, and pH value on the morphology and volume-phase transition temperature of two-shell magnetic composite hollow latex particles was studied. Moreover, the latex particles were used as carriers to load with caffeine, and the caffeine-loading characteristics and caffeine release rate of latex particles were also studied. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 00, 000–000

The poly(N-isopropylacrylamide-methylacrylate acid) (poly(NIPAAm–-MAA))/Fe₃O₄/poly(NIPAAm-MAA) two-shells magnetic composite hollow latex particles were synthesized by four-steps reaction. Many factors such as reactant concentration, monomer ratio, and pH value influence the morphology of composite latex particles significantly. A transmission electron microscopy was used to observe the appearance morphology and cross-section morphology of magnetic composite latex particles that are shown as (a) and (b) respectively. The results appear that the latex particles possessed a hollow structure.

A new poly(3-dodecyltellurophene) (P3DDTe) was synthesized through a Suzuki polymerization reaction and the optoelectronic properties of P3DDTe were described.

Copolymers of ethylene and ethyl acrylate have been widely used as commodity materials in many fields. In this article, a general synthetic strategy toward fine tuning the ethyl acrylate content and facile control over the monomer sequence regularity of this important type of copolymer via acyclic diene metathesis (ADMET) polymerization followed by hydrogenation is demonstrated. Three structurally symmetric diene monomers (M1–M3) were synthesized in good yields via a three-step synthetic approach; each of the monomers contains two tail-to-tail linked ethyl acrylate units connected to the terminal alkenes by a methylene spacer with specific length. ADMET homopolymerization of M1–M3 and copolymerization of these monomers with 1,9-decadiene were conducted, and after hydrogenation, a family of periodic and random copolymers of ethylene and ethyl acrylate were obtained. All the polymer samples were characterized by gel permeation chromatography and nuclear magnetic resonance, and the thermal properties of the saturated copolymers were investigated with thermal gravimetric analysis and differential scanning calorimetry. The glass transition and melting behaviors of this family of ethylene and ethyl acrylate copolymers were found to be dependent on the ethyl acrylate content and the primary structure regularity in copolymers. Copolymers with low ethyl acrylate content and periodic microstructures exhibited better crystallinity. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Periodic and random ethylene–ethyl acrylate copolymers were synthesized via acyclic diene metathesis (co)polymerization. Differential scanning calorimetry results indicated that copolymers with low ethyl acrylate content and regular primary structure exhibited better crystallinity.

Well-defined polymethylene-block-polystyrene (PM-b-PS) diblock copolymers were synthesized via a combination of polyhomologation of ylides and reversible addition-fragmentation chain-transfer (RAFT) polymerization of styrene. Trithiocarbonate-terminated polymethylenes (PM-TTCB) (M_n = 1400 g mol⁻¹; M_w/M_n = 1.09 and M_n = 2100 g mol⁻¹; M_w/M_n = 1.20) were obtained via an esterification of S−1-dodecyl-S′-(α,α′-dimethyl-α″-acetate) trithiocarbonate with hydroxyl-terminated polymethylene synthesized via polyhomologation of ylides followed by oxidation. Then, a series of PM-b-PS (M_n = 5500–34,000 g mol⁻¹; M_w/M_n = 1.12–1.25) diblock copolymers were obtained by RAFT polymerization of styrene using PM-TTCB as a macromolecular chain-transfer agent. The chain structures of all the polymers were characterized by proton nuclear magnetic resonance (¹H NMR), gel permeation chromatography, and Fourier transform infrared spectroscopy. The thiocarbonylthio end-group of PM-b-PS was transformed into thiol group by aminolysis and confirmed by UV–vis spectroscopy. In addition, microfibers and microspheres of such diblock copolymers were fabricated by electrospinning process and observed by scanning electron microscopy (SEM). © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Well-defined polymethylene-b-polystyrene (PM-b-PS) diblock copolymers were synthesized via a combination of polyhomologation of ylides and reversible addition-fragmentation chain-transfer polymerization. The terminal thiocarbonylthio group of PM-b-PS was efficiently transformed into thiol group by aminolysis. The microspheres and microfibers of PM₁-b-PS₃ were fabricated by an electrospinning process using dimethylformamide and DMF-CHCl₃ as solvents and observed by SEM.

Novel bromine-functionalized photocrosslinkable low-bandgap copolymers, PBDTTT-Br25 and PBDTTT-Br50, are synthesized via Stille cross-coupling polymerization for the purpose of stabilizing the film morphology in polymer solar cells (PSCs). Photocrosslinking of PBDTTT-Br25 and PBDTTT-Br50 copolymers dramatically improves the solvent resistance of the active layer without disrupting the molecular ordering and charge transport, which is confirmed by the insolubility of the films washed by organic solvents and by their thermal behavior. As a result, the formation of large aggregations of fullerene is suppressed in polymer:fullerene blend films even after prolonged thermal annealing, and the stability of the device is enhanced when compared with cells based on noncrosslinkable PBDTTT. The power conversion efficiency of the PSCs based on PBDTTT-Br25 and PBDTTT-Br50 reaches 5.17% and 4.48%, respectively, which is improved obviously in comparison with that (4.26%) of the PSCs based on the control polymer PBDTTT. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Novel bromine-functionalized photocrosslinkable low-bandgap copolymers, PBDTTT-Br25 and PBDTTT-Br50, were synthesized via Stille cross-coupling polymerization for the purpose of stabilizing the film morphology in polymer solar cells (PSCs). The formation of large aggregations of fullerene was suppressed in polymer:fullerene blend films even after prolonged thermal annealing, and the stability of the device was enhanced when compared with cells based on noncrosslinkable PBDTTT. Our approach paves a way toward solvent-robust and operation-stable PSCs.

Hyperbranched vinyl polymers with high degrees of branching (DBs) up to 0.43 functionalized with numerous pendent allene groups have been successfully prepared via reversible addition fragmentation chain transfer polymerization of a state-of-art allene-derived asymmetrical divinyl monomer, allenemethyl methacrylate (AMMA). The gelation did not occur until high monomer conversions (above 90%), as a result of the optimized reactivity difference between the two vinyl groups in AMMA. The branched structure was confirmed by a combination of a triple-detection size exclusion chromatography (light scattering, refractive index, and viscosity detectors) and detailed ¹H NMR analyses. A two-step mechanism is proposed for the evolution of branching according to the dependence of molecular weight and DB on monomer conversion. Controlled radical polymerization proceeds until moderate conversions, mainly producing linear polymers. Subsequent initiation and propagation on the polymerizable allene side chains as well as the coupling of macromolecular chains generate numerous branches at moderate-to-high monomer conversions, dramatically increasing the molecular weight of the polymer. AMMA was also explored as a new branching agent to construct poly(methyl methacrylate)-type hyperbranched polymers by its copolymerization with methyl methacrylate. The DB can be effectively tuned by the amount of AMMA, showing a linear increase trend. The pendent allene groups in the side chains of the copolymers were further functionalized by epoxidation and thiol-ene chemistry in satisfactory yields. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Hyperbranched vinyl polymers with high degrees of branching and numerous functional pendent allene groups have been successfully prepared via RAFT polymerization of a new allene-derived asymmetrical divinyl monomer.

In this work, Fe(0)-mediated single electron-living radical copolymerization of styrene (St) and acrylamide (AM) was investigated at ambient temperature in N,N-dimethylformamide using carbon tetrachloride as initiator and tetramethylethylenediamine as ligand. Kinetic studies showed that the copolymerization followed the first-order kinetics model. The resulting copolymers of St and AM possessed predetermined molecular weights and narrow molecular weight distribution, which agreed with the character of controlled/living polymerization. On the basis of Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (NMR), the monomer reactivity ratios were calculated. The amount of ligand played an important role in copolymerization. The obtained polymer was characterized by FTIR, ¹H NMR, ¹³C NMR, and gel permeation chromatography. The living characteristics were demonstrated by chain extension experiment. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Copolymers of PSt-co-AM were synthesized by SET LRP 25 °C in DMF using CCl₄ as initiator with Fe(0)/TMEDA catalytic system. SET LRP technique was successfully developed by the group of Percec with the aim of reducing the catalyst concentration and the polymerization was performed at an ambient temperature. The macroinitiator has a M_n,GPC of 4700 g/mol and polydispersity index of 1.16 with the resulting copolymer having an experimentally determined M_n,GPC of 21,500 g/mol and polydispersity index of 1.60. The GPC traces indicated extremely high initiation efficiency with the resulting copolymer.

Biomass-derived furfuryl methacrylate (FMA) has been successfully polymerized for the first time by anionic polymerization to produce atactic (at-), isotactic (it-), or syndiotactic (st-) poly(furfuryl methacrylate) (PFMA), depending on initiator structure and reaction conditions. Thermal properties of the PFMA materials are strongly affected by the polymer tacticity. Most notably, while both isotactic and syndiotactic polymers can undergo inter- or intrachain crosslinking reactions when heated to 290 °C, there is no evidence for the atactic polymer to perform the same reaction. Furthermore, the PFMA tacticity also greatly affects the amount of stable carbonaceous materials it produces when heated to 650 °C, with st-PFMA forming the largest amount of such materials (26.9%), as compared to only 5.6% by at-PFMA. Using the Diels–Alder (DA) “click reaction” between the reactive furfuryl group within the PFMA polymers as the diene equivalent and a bismaleimide as the dienophile, thermoreversible smart polymers have been successfully prepared. Thermoreversibility of the preformed crosslinked polymers has been demonstrated, thanks to the facile retro-DA reaction upon heating and the DA reaction upon cooling of such self-healing materials. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

Biomass-derived furfuryl methacrylate has been successfully polymerized for the first time by anionic polymerization, leading to tactic or atactic polymers that exhibit sharply different thermal properties related to crosslinking and stable carbonaceous materials formation.

A new polymer blend comprised of a hydrogenated ring-opening polymer with an ester group as positive polymer and hydroxyl functionalized polystyrene as negative one produced the excellent transparent materials, which enabled a precise birefringence control in keeping with the other physical properties for optical film use. The excellent transparency even above those of T_g was attributed to a depressed phase separation that resulted from strong hydrogen bond between the ester and hydroxyl groups.

Two series of novel electro-optic (EO) polycarbonates containing two different kinds of nonlinear optical (NLO) chromophores with tricyanofurane (TCF) electron acceptor have been successfully prepared through the facile polycondensation between diol NLO chromophore and bisphenol A bis(chloroformate). These new polycarbonates which were characterized by ¹H-NMR and Fourier transform infrared exhibited good solubility in common polar organic solvents. They also showed glass transition temperatures (T_g) in the range of 124–156 °C. The morphology studies indicated that these polycarbonates had good film quality before and after corona poling. The EO coefficients (r₃₃) of two polycarbonates films were up to 45 pm/V (PC-TCFC-2) and 75 pm/V (PC-DFTC-3) at the wavelength of 1310 nm. Moreover, good temporal stability of the poling-induced dipole alignment was also achieved, and the resulting poled films of PC-TCFC-2 and PC-DFTC-3 could retain 90 and 80% of the initial EO activities at 85 °C for more than 500 h, respectively. Both EO activity and temporal stability results were better than the guest–host EO polymers containing the same concentration chromophores, which indicated that such kind of polycarbonates could effectively suppress the intermolecular electrostatic interaction and translate microscopic molecular hyperpolarizability into macroscopic EO activity. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013.

Electro-optic (EO) polycarbonates were prepared through copolymerization of the diol nonlinear optical chromophores and bisphenol A with bisphenol A bis(chloroformate) in solution. The obtained polycarbonates exhibited good film-forming properties and good thermal stability. The poled films of the resultant electro-optic polycarbonates revealed the maximum EO coefficient of 75 pm/V. Moreover, the obtained poled films also possessed better temporal stability. These good performances endow the resultant EO polycarbonates with device application in photonics.

Common CO₂-based biodegradable polycarbonates like poly(propylene carbonate) or poly(cyclohexene carbonate) are generally hydrophobic, leading to slow biodegradation rate and poor cell adhesion, which limit their applications in the biomedical field. Here hydrophilic polycarbonates were prepared by one-pot terpolymerization of CO₂, propylene oxide (PO), and 2-((2-(2-(2-methoxyethoxy)ethoxy)ethoxy)methyl)oxirane (ME₃MO) using binary Salen Co(III)-Cl/PPNCl catalyst system. The resultant terpolymers showed one glass transition temperature (T_g), which decreased with the increase of ME₃MO units in the terpolymers (F_ME3MO). Water contact angles of the resultant terpolymers with F_ME3MO of 4.2−23.6% were 68−25°, while that of poly(propylene carbonate) was 90°, indicating that the terpolymers became hydrophlilic. Furthermore, the terpolymers with F_ME3MO more than 25.8% exhibited reversible and rapid thermo-responsive property in water, and the lower critical solution temperature (LCST) was highly sensitive to F_ME3MO. In particular, aqueous solution of the terpolymer with F_ME3MO of 72.6% showed a LCST around 35.2 °C, close to body temperature, which was promising for biomedical applications, especially for in vivo applications. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013.

Hydrophilic CO2-based biodegradable polycarbonates are designed and prepared. The resultant terpolymers are more hydrophlilic than PPC; water contact angles of the terpolymers with 4.2–23.6% of F_ME3MO were 68–25°. Furthermore, the terpolymers with >25.8% of F_ME3MO showed rapid and reversible thermo-responsive property in water, whose LCST ranged from 7 to 36.2 °C.

Thiol-ene radical addition by photolysis is a highly efficient click reaction of sufhydryl groups with reactive enes that has been extensively explored as a promising means to construct multifunctional materials. Here, photo-induced thiol-ene crosslinked films composed of linear methacrylate copolymer polythiols (MCPsh) are reported. Well-defined MCPsh copolymers were prepared by thiol-responsive cleavage of pendant disulfide linkages positioned in the corresponding methacrylate copolymers with narrow molecular weight distribution which were synthesized by a controlled radical polymerization method. With a commercially available multifunctional acrylate as a model ene, photo-induced thiol-ene radical polyaddition of these polythiols is competitive to free-radical homopolymerization of acrylates, yielding crosslinked films exhibiting rapid cure, uniform network, and enhanced mechanical properties; these properties are required for high performance coating materials. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013.

New photo-induced thiol-ene crosslinked films composed of linear methacrylate copolymer polythiols, exhibiting rapid cure, uniform network, and enhanced mechanical properties for surface coatings applications.

The aim of this study was to investigate the effect of the asymmetry of the triblock copolymers on their thermoresponsive self-assembly behavior. To this end, nine ABA-type triblock copolymers with n-butyl methacrylate and 2-(dimethylamino)ethyl methacrylate (DMAEMA) consisting of the A and the B blocks, respectively, were synthesized. Polymers of three different DMAEMA contents (50, 60, and 70 wt %) were synthesized while varying the length ratio of the two hydrophobic A blocks. Specifically, one symmetric ABA triblock copolymer and two asymmetric ABA′ triblock copolymers with the length of the second A block to be twice or four times bigger than the length of the first A block (AB2A and AB4A triblock copolymer) were synthesized for each DMAEMA composition. Three statistical copolymers were also synthesized for comparison. The thermoresponsive behavior of the copolymers was studied and it was found that the cloud point and rheological properties of the polymers were strongly affected by the architecture (statistical vs. block) and less strongly by the DMAEMA composition and the asymmetry of the polymers. Nevertheless, interestingly the asymmetry of the ABA triblock copolymers did influence the thermoresponsive behavior with the more symmetric polymers presenting a sol–gel transition at lower temperatures. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013.

Thermoresponsive ABA triblock copolymers form flower-like micelles at room temperature and gels at higher temperatures and concentrations. Interestingly, this is influenced by the asymmetry of the triblocks; the more symmetric the architecture the lower the sol–gel temperature.

Well-defined amphiphilic A₈B₄ miktoarm star copolymers with eight poly(ethylene glycol) chains and four poly(ε-caprolactone) arms (R-8PEG-4PCL) were prepared using “click” reaction strategy and controlled ring-opening polymerization (CROP). First, multi-functional precursor (R-8N₃-4OH) with eight azides and four hydroxyls was synthesized based on the derivatization of resorcinarene. Then eight-PEG-arm star polymer (R-8PEG-4OH) was prepared through “click” reaction of R-8N₃-4OH with pre-synthesized alkyne-terminated monomethyl PEG (mPEG-A) in the presence of CuBr/N,N,N′,N″,N″′- pentamethyldiethylenetriamine (PMDETA) in DMF. Finally, R-8PEG-4OH was used as tetrafunctional macroinitiator to prepare resorcinarene-centered A₈B₄ miktoarm star copolymers via CROP of ε-caprolactone utilizing Sn(Oct)₂ as catalyst at 100 °C. These miktoarm star copolymers could self-assemble into spherical micelles in aqueous solution with resorcinarene moieties on the hydrophobic/hydrophilic interface, and the particle sizes could be controlled by the ratio of PCL to PEG. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013.

Well-defined resorcinarene-centered A₈B₄ miktoarm star copolymers were synthesized. These copolymers could self-assemble into spherical in aqueous solution with resorcinarene moieties on the hydrophilic/hydrophobic interface.

We present an efficient method for synthesis of block copolymer by radical addition cross-coupling reaction between two different polymeric radicals and different double bonds. Two different monobromo polymers (P₁-Br and P₂-Br) were reacted with Cu(0)/N,N,N′,N″,N″-pentamethyldiethylenetriamine in the presence of ethyl dithiobenzoate or 1,1-diphenylethylene (X) and the block copolymer (P₁-X-P₂) can be obtained with high efficiency, which cannot be prepared by normal atom transfer radical coupling of mixture of P₁-Br and P₂-Br. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013.

Block copolymer (P₁-X-P₂) are synthesized by radical addition cross-coupling reaction between two different polymeric radicals in-situ generated by two different bromopolymers (P₁-Br and P₂-Br) in the presence of ethyl dithiobenzoate or 1,1-diphenylethylene (X), which cannot be prepared by normal ATRC of mixture of P₁-Br and P₂-Br.

A new method to synthesize a variety of well-controlled polylactide (PLA)-based block copolymers having disulfide linkages at block junctions (PLA-ss-PATRPs) was investigated. The method uses a combination of ring-opening polymerization (ROP) and atom transfer radical polymerization (ATRP) that initiates the synthesis of a new disulfide-labeled double-head initiator having both terminal OH and Br groups (HO-ss-iBuBr). The amount of tin catalyst and polymerization time significantly influenced the control of ROP initiated with HO-ss-iBuBr. A series of ATRP of various methacrylates as well as acrylate and styrene in the presence of the resulting PLA-ss-iBuBr macroinitiators proceeded in a living manner. These well-controlled PLA-ss-PATRPs were further characterized for thermal properties using differential scanning calorimetry and thiol-responsive degradation upon the cleavage of disulfide linkages. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012

A new method using ring-opening polymerization and atom transfer radical polymerization that initiate a new disulfide-labeled double-head initiator for the synthesis of a variety of well-controlled polylactide-based block copolymers having disulfide linkages at block junctions.

Water-soluble luminescent material was developed by introducing europium (Eu(III)) ions into the core of a star polymer. Living radical polymerization was used to obtain the star polymer. The strategy to introduce Eu(III) ions into the star polymer was studied using poly(methyl methacrylate) as an arm. The best Eu(III) ion introduction was obtained by simultaneous introduction, resulting in about 30 µmol/g-polymer, which needed only one step for synthesis. The utilization of a hydrophilic polymer such as poly(ethylene oxide) (PEO) as an arm produced a water-soluble star polymer. The Eu(III)-bearing PEO star polymer obtained in this study was water soluble and showed fluorescence. In addition, it was stable in water after 1 month. The Eu(III)-bearing star polymer exhibited luminescent properties under UV light irradiation with relatively high quantum yields of 60% in organic solution and 19% in aqueous solution. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2527–2535

Eu(III)-bearing star polymers are synthesized in a simple and effective method of one-step introduction by living radical copolymerization of Eu(III) complex monomer [Eu(SDPO)] and divinyl linking monomer ethylene glycol dimethacrylate. A water-soluble Eu(III)-bearing star polymer is obtained using PEO as an arm, and is stable in water for 1 month. All of Eu(III)-bearing star polymers is showing red luminescence under UV irradiation.

We synthesized and characterized three new amorphous dithienylbenzothiadiazole (TBT)-triphenylamine (TPA) polymers for application in bulk-heterojunction (BHJ) organic photovoltaic (OPV) cells. Poly(3HTBT-TPA) has hexyl side chains on the thienyl groups (pointing toward the benzothiadiazole (BTD) unit), and poly(4HTBT-TPA) has hexyl side chains on the thienyl groups (pointing outward from the BTD unit). The incident photon to current conversion efficiencies (IPCEs) in the region from 550 to 650 nm for the OPV cells prepared using poly(4HTBT-TPA) were higher than those for the OPV cells prepared using poly(3HTBT-TPA) because the absorption spectrum for the poly(4HTBT-TPA) has a slightly red-shifted absorption edge. We also demonstrated that the poly(4HTBT-TPA)-based OPV performance is independent of the fabrication process, so using an amorphous film to fabricate BHJ OPV cells offers great advantages over using a polycrystalline film in terms of the high reproducibility of the OPV performance. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2536–2544

New amorphous dithienylbenzothiadiazole (TBT)-triphenylamine (TPA) polymers were synthesized for application in bulk-heterojunction (BHJ) organic photovoltaic (OPV) cells. The incident photon to current conversion efficiencies (IPCEs) in the region from 550 to 650 nm for the OPV cells prepared using poly(4HTBT-TPA) were higher than those for the OPV cells prepared using poly(3HTBT-TPA) because the absorption spectrum for the poly(4HTBT-TPA) has a slightly red-shifted absorption edge.

The work focuses on the design, synthesis, and characterization of a series of mesogen-jacketed liquid crystalline polymers (MJLCPs) based on the octyl substituted biphenyl mesogenic core through different linkage groups. The molecular characterizations of the polymers obtained by conventional free radical polymerization were performed with ¹H NMR, gel permeation chromatography, and thermogravimetric analysis. Their thermotropic liquid crystalline (LC) behaviors were investigated in detail by a combination of various techniques, such as polarized light microscopy, differential scanning calorimetry, and 1D and 2D wide-angle X-ray diffraction. Our results showed that all the polymers were thermally stable, and their LC phases were greatly dependent on the linking groups between the biphenyl mesogenic core and terminal alkyl group substituent. Polymers with ether/ester or ether linkage group exhibited an unusual phase behavior with temperature increasing, tetragonal columnar nematic LC phase, or columnar nematic phase developed at high temperatures for the polymers transformed into amorphous phase during cooling process, showing a re-entrant phase behaviors. However, polymers with ester linkage group were not LC with temperature varied. It is illustrated that subtle changes in the molecular structure brought about tremendous variation of the LC phase properties for MJLCPs. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2545–2554

A series of new mesogen-jacketed liquid crystalline (LC) polymers based on biphenyl mesogenic core with terminal alkyl through different connecting linkage groups were successfully synthesized. Phase transitions and phase structures of the polymers were investigated in detail, and dependence of the phase transformations on their structures was visually found. Polymers with ether/ester or ether linkage group exhibited an unusual phase behavior with temperature increasing, and tetragonal columnar nematic LC phase or columnar nematic phase developed at high temperatures transformed into amorphous phase during cooling process, showing a re-entrant phase behaviors. However, polymers with ester linkage group were not LC even at high temperatures.

A reddish-brown fluoroalkyl end-capped 2-acrylamido-2-methylpropanesulfonic acid (AMPS) oligomer/acetone composite was prepared by heating the white oligomer powder with acetone at 80 °C for 3 h. The color was not observed in the corresponding non-fluorinated AMPS oligomer/acetone composite, which was prepared under similar conditions. The coloring was probably caused by the formation of acetone polyaldol condensation products in the fluorinated oligomeric gel network cores. The colored R_F-(AMPS)_n-R_F/acetone composite powders were stable and did not exhibit any color change after 2 years in natural light at room temperature. The colored composite powders dissolved in methanol to give a reddish-brown solution at room temperature. However, the retro-polyaldol condensation decolored the solution after 1 day at room temperature. This is the first example of the retro-aldol polycondensation of acetone under mild conditions. The decoloration increased by between 38- and 70-fold under UV irradiation, compared with that in dark conditions. The coloring–decoloring behavior was consistent and repeatable; therefore our fluorinated oligomer/acetone composites are promising candidates for new fluorinated coloring materials. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2555–2564

Coloring–decoloring behavior of R_F-(AMPS)_n-R_F/acetone composite possessing a good repeatability.

Aryloxo-modified half-titanocenes, Cp′TiCl₂(O-2,6-ⁱPr₂C₆H₃) [Cp′ = Cp* (1), ^tBuC₅H₄ (2)], catalyze terpolymerization of ethylene and styrene with α-olefin (1-hexene and 1-decene) efficiently in the presence of cocatalyst, affording high-molecular-weight polymers with unimodal distributions (compositions). Efficient comonomer incorporations have been achieved by these catalysts. The content of each comonomer (α-olefin, styrene, etc.) could be controlled by varying the comonomer concentration charged, and resonances ascribed to styrene and α-olefin repeated insertion were negligible. The terpolymerization with p-methylstyrene (p-MS) in place of styrene also proceeded in the presence of [PhN(H)Me₂][B(C₆F₅)₄] and AlⁱBu₃ cocatalyst, and p-MS was incorporated in an efficient matter, affording high-molecular-weight polymers with uniform molecular weight distributions. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2565–2574

Aryloxo-modified half-titanocenes, Cp′TiCl₂(O-2,6-ⁱPr₂C₆H₃) [Cp′ = Cp* (1), ^tBuC₅H₄ (2)], catalyze terpolymerization of ethylene and styrene with α-olefin (1-hexene and 1-decene) efficiently in the presence of cocatalyst, affording high-molecular-weight polymers with unimodal distributions (compositions). The content of each monomer could be controlled by varying the comonomer concentration charged, and resonances ascribed to styrene and α-olefin repeated insertion were negligible. The terpolymerization with p-methylstyrene in place of styrene also proceeded in the presence of [PhN(H)Me₂][B(C₆F₅)₄] and AlⁱBu₃ cocatalyst, affording high-molecular-weight polymers with uniform distributions.

Ethylene copolymerizations with norbornene (NBE) using half-titanocenes containing imidazolin-2-iminato ligands, Cp′TiCl₂[1,3-R₂(CHN)₂CN] [Cp′ = Cp (1), ^tBuC₅H₄ (2); R = ^tBu (a), 2,6-ⁱPr₂C₆H₃ (b)], have been explored in the presence of methylaluminoxane (MAO) cocatalyst. Complex 1a exhibited remarkable catalytic activity with better NBE incorporation, affording high-molecular-weight copolymers with uniform molecular weight distributions, whereas the tert-BuC₅H₄ analog (2a) showed low activity, and the resultant polymer prepared by the Cp-2,6-diisopropylphenyl analog (1b) possessed broad molecular weight distribution. The microstructure analysis of the poly(ethylene-co-NBE)s prepared by 1a suggests the formation of random copolymers including two and three NBE repeating units. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2575–2580

Half-titanocenes containing imidazolin-2-iminato ligands, CpTiCl₂[1,3-^tBu₂(CHN)₂CN], exhibited remarkable catalytic activities with better norbornene (NBE) incorporations for ethylene copolymerization with norbornene in the presence of MAO cocatalyst, affording high-molecular-weight copolymers with uniform molecular weight distributions as well as with high NBE contents (high glass transition temperature, T_g = 230–258 °C). The microstructure analysis of the poly(ethylene-co-NBE)s suggests the formation of random copolymers including two and three NBE repeating units.

An efficient introduction of vinyl group into poly (ethylene-co-styrene) or poly(ethylene-co−1-hexene) has been achieved by the incorporation of 3,3′-divinylbiphenyl (DVBP) in terpolymerization of ethylene, styrene, or 1-hexene with DVBP using aryloxo-modified half-titanocenes, Cp′TiCl₂(O−2,6-ⁱPr₂C₆H₃) [Cp′ = Cp*, ^tBuC₅H₄, 1,2,4-Me₃C₅H₂], in the presence of MAO cocatalyst, affording high-molecular-weight polymers with unimodal distributions. Efficient comonomer incorporations have been achieved by these catalysts, and the content of each comonomer could be varied by its initial concentration charged. The postpolymerization of styrene was initiated from the vinyl group remained in the side chain by treatment with n-BuLi. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2581–2587

Introduction of vinyl group into poly(ethylene-co-styrene) or poly(ethylene-co−1-hexene) has been achieved by the incorporation of 3,3′-divinylbiphenyl (DVBP) in terpolymerization of ethylene, styrene, or 1-hexene with DVBP using aryloxo-modified half-titanocenes, Cp′TiCl₂(O−2,6-ⁱPr₂C₆H₃) [Cp′ = Cp*, ^tBuC₅H₄, 1,2,4-Me₃C₅H₂], and MAO catalysts. Efficient comonomer incorporations have been achieved by these catalysts, and the content of each comonomer could be varied by its concentration charged; postpolymerization of styrene was initiated from the vinyl group by treatment with n-BuLi.

Synthetic glycopolymers are important natural oligosaccharides mimics for many biological applications. To develop glycopolymeric drugs and therapeutic agents, factors that control the receptor-ligand interaction need to be investigated. A library of well-defined glycopolymers has been prepared by the combination of copper mediated living radical polymerization and CuAAC click reaction via post-functionalization of alkyne-containing precursor polymers with different sugar azides. Employing Concanavalin A as the model receptor, we explored the influence of the nature and densities of different sugars residues (mannose, galactose, and glucose) on the stoichiometry of the cluster, the rate of the cluster formation, the inhibitory potency of the glycopolymers, and the stability of the turbidity through quantitative precipitation assays, turbidimetry assays, inhibitory potency assays, and reversal aggregation assays. The diversities of binding properties contributed by different clustering parameters will make it possible to define the structures of the multivalent ligands and densities of binding epitopes tailor-made for specific functions in the lectin-ligand interaction. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2588–2597

Multivalent carbohydrate interactions play an important role in many biological processes. It is critical to understand and design the optimum glycopolymer structure to interact with the desired lectin. In this study, we have investigated the binding properties of a glycopolymer library to Con A via quantitative precipitation assay, turbidimetry assay, inhibitory potency assay and reversal aggregation assay.

Poly(1-oxodimethylene) was synthesized via oxidation of poly(vinyl alcohol) with a hydrogen peroxide/hydrobromic acid system. The content of the carbonyl groups in poly(1-oxodimethylene) depended on the amount of water added, and lower amounts of water were suitable for efficient oxidation due to higher acidity of the reaction system. The highest content of carbonyl groups was estimated to be above 88% by the titration with hydrazine that reacted with the carbonyl groups in poly(1-oxodimethylene). The obtained poly(1-oxodimethylene) complexed with Cu and Ni ions under basic conditions. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2598–2605

Poly(1-oxodimethylene) was synthesized via metal free oxidation of poly(vinyl alcohol) with a hydrogen peroxide/hydrobromic acid system. The obtained polymer mainly consisted of repeating β-diketone structures with the keto-enol tautomerism tilting toward the enol form. The conjugation was confirmed by IR spectroscopy showing broad absorption of the carbonyl groups at 1597–1712 cm⁻¹. The obtained poly(1-oxodimethylene) formed polymeric metal complexes with Ni and Cu acetates.

A series of selenium-substituted carbonates, S,Se-dibenzyl dithioselenocarbonate (DTSC), S,Se-dibenzyl thiodiselenocarbonate (TDSC), and Se,Se-dibenzyl triselenocarbonate (TSC), were synthesized and used as mediators in radical polymerization. The results indicate that these selenium-substituted carbonates can control the polymerization of styrene (St) and methyl acrylate, as evidenced by the number-average molecular weight that increased linearly with the monomer conversion, molecular weights that agreed well with the predicted values, and successful chain extensions. The treatment of the resultant polystyrene by hydrogen peroxide generated polymers with approximately half-reduced molecular weights, and the absence of carbonate groups and vinyl double bond-terminated chain ends. The polymerization with these selenium-substituted carbonates was the same polymerization mechanism as their analogue, the widely used S,S-dibenzyl trithiocarbonate. This work provided a flexible protocol to incorporate selenium into the polymer chain backbone. Specifically, the treatment of these polymers by oxidation produced “clickable” vinyl-terminated chain ends, which provided possibilities for further functionalization, for example, via a thiol-ene click reaction. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2606–2613

A series of selenium-substituted carbonates conveyed controls over the polymerization of styrene and methyl acrylate, affording a flexible protocol to incorporate selenium into the polymer chain backbone. The treatment of the polymers by oxidation produced “clickable” vinyl-terminated chain ends, which provided the possibility for further functionalization, for example, via a thiol-ene click reaction.

Hyperbranched polyglycerols (HPGs) are globular structures with a large number of functionalizable hydroxyl groups and have excellent in vitro and in vivo biocompatibility profiles comparable to polyethylene glycol. This work introduces a facile method for the synthesis of medium molecular weights (M_ws) (50–300 kDa) HPGs, which has been difficult to synthesize with low polydispersity, with the assistance of solvents by ring opening polymerization. The influence of different solvents (1,4-dioxane, tetrahydropyran (THP), ethylene glycol diethyl ether (EGDE) and decane), solvent to glycidol ratio, concentration of glycidol and the time of polymerization on M_w and polydispersity of HPGs has been studied. The M_w and polydispersity of HPGs are significantly affected by the nature of the polymerization phase (homogeneous or heterogeneous) and chemical structure of the solvent. The differences in the solvation of the potassium cations and change in the nucleophilicity of the alkoxide anion in various solvents may be responsible for the changes in M_w and PDI of the HPG. The M_w of the HPG decreases in the order 1,4-dioxane > THP > EGDE >decane. The microstructure, solution and thermal properties of the HPG do not depend on the nature of solvent. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2614–2621

A novel method for the synthesis of medium and high molecular weights (50–500 kg/mol) of hyperbranched polyglycerols (HPG) has been reported. The influence of various solvents on anionic ring opening polymerization glycidol has been investigated. We found that that the structure of solvents had a profound effect on polymerization and the molecular weight of HPG formed. The differences in the solvation of the K⁺ and change in the nucleophilicity of the alkoxide anion in various solvents may be responsible for the observation.

Three alternating donor–acceptor copolymers have been synthesized by Stille coupling polymerization of 2,6-(trimethyltin)−4,8-bis(5-dodecylthiophene-2-yl)benzo[1,2-b:4,5-b′]dithiophene with 1,3-dibromo-5-hexylthieno[3,4-c]pyrrole-4,6-dione, 4,7-dibromo-1,3-benzothiadiazole, and 5,7-dibromo-2,3-didodecylthieno[3,4-b]pyrazine, respectively. The synthesized polymers were tested in bulk heterojunction solar cells as blends with the acceptor [6,6]-phenyl-C₆₁-butyric acid methyl ester (PCBM). The thienopyrroledione copolymer displayed a power conversion efficiency of 3.00% which was increased to 3.86% by application of the additive 1,8-diiodooctane (DIO). Tapping mode atomic force microscopy analysis indicated that there was an increase in the phase separation between polymer and PCBM, leading to an improvement in the performance upon the addition of DIO. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2622–2630

Three donor–acceptor copolymers have been synthesized by Stille coupling polymerization of 2,6-(trimethyltin)−4,8-bis(5-dodecylthiophene-2-yl)benzo[1,2-b:4,5-b′]dithiophene with 1,3-dibromo-5-hexylthieno[3,4-c]pyrrole-4,6-dione,4,7-dibromo-1,3-benzothiadiazole, and 5,7-dibromo-2,3-didodecylthieno[3,4-b]pyrazine, respectively. The synthesized polymers were tested in bulk heterojunction solar cells as blends with the acceptor [6,6]-phenyl-C₆₁-butyric acid methyl ester. The thienopyrroledione donor–acceptor polymer displayed a power conversion efficiency of 3.00% which was increased to 3.86% by application of the additive 1,8-diiodooctane.

A series of networked polymers bearing isocyanurate moiety was synthesized by cyclotrimerization of diisocyanates, with employing methylenediphenyl 4,4′-diisocyanate and 1,6-hexamethylenediisocyanate (HMDI) in several feed ratios. In spite of the large difference in intrinsic reactivity between these two diisocyanates, their coannulation proceeded efficiently by using sodium p-toluenesulfinate (pTolSO₂Na) and 1,3-dimethyl-2-imidazolidinone as a catalyst and a solvent, respectively. The resulting networked polymers were transparent and exhibited excellent thermal stability. In addition, HMDI-rich feed ratios allowed for the formation of networked polymers with increased flexibility. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2631–2637

A series of networked polymers bearing isocyanurate moiety were synthesized by cyclotrimerization of diisocyanates, with employing methylene diphenyl 4,4′-diisocyanate and 1,6-hexamethylenediisocyanate (HMDI) in several feed ratios. In spite of the large difference in intrinsic reactivity between these two diisocyanates, their coannulation proceeded efficiently by using sodium p-toluenesulfinate and 1,3-dimethyl-2-imidazolidinone as a catalyst and a solvent, respectively. The resulting networked polymers were transparent and exhibited excellent thermal stability. In addition, HMDI-rich feed ratios allowed for the formation of networked polymers with increased flexibility.

Structural isomers of thermo-oxidatively stable poly(carborane-siloxane-arylacetylene) (PCSAA), namely, m-PCSAA and p-PCSAA, were synthesized by the reaction of the dimagnesium salts of m-diethynylbenzene or p-diethynylbenzene with 1,7-bis(chlorotetramethyldisiloxyl)-m-carborane. The developed polymers have exceptional thermo-oxidative properties similar to their diacetylene counterpart poly(carborane-siloxane-acetylene), PCSA. Thermal treatment of either of the PCSAAs results in a fully crosslinked thermoset by 500 °C resulting from the cycloaddition reactions involving the acetylene and aryl functionalities and subsequent formation of bridging disilylmethylene entities as discerned from Fourier transform infrared, ¹³C and ²⁹Si solid-state NMR, and XPS studies. X-ray diffraction analysis revealed that the thermosets obtained from p-PCSAA possess enhanced crystallinity when compared to that obtained from m-PCSAA possibly due to more efficient packing interactions of the p-diethynylbenzene groups during thermoset formation. The presence of the aryl groups in the backbone of the PCSAAs' chains appeared to have enhanced the storage and bulk moduli of their thermosets when compared to the thermoset of PCSA. Dielectric studies of m-PCSAA and p-PCSAA revealed segmental relaxation peaks, α, above their glass transition temperatures with p-PCSAA exhibiting a broader peak with a slower relaxation rate than m-PCSAA. © 2013 Wiley Periodicals, Inc.^† J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2638–2650

Thermo-oxidatively-stable structural isomers m-PCSAA and p-PCSAA have exceptional thermo-oxidative properties similar to PCSA. Their thermal treatment results in thermosets by the cycloadditions of acetylenes and aryls and subsequent formation of disilylmethylene entities. Thermoset of p-PCSAA appear more crystalline than that from m-PCSAA by XRD analysis. The aryl groups in the backbone of the PCSAAs' chains enhance the storage and bulk moduli of their thermosets when compared to that from PCSA. m-PCSAA and p-PCSAA exhibit segmental relaxation peaks, α, above their glass transition temperatures with p-PCSAA showing a broader peak with a slower relaxation rate than that of m-PCSAA.

One-step synthesis of block-graft copolymers by reversible addition-fragmentation chain transfer (RAFT) and ring-opening polymerization (ROP) by using a novel initiator was reported. Block-graft copolymers were synthesized in one-step by simultaneous RAFT polymerization of n-butylmethacrylate (nBMA) and ROP of ε-caprolacton (CL) in the presence of a novel macroinitiator (RAFT-ROP agent). For this purpose, first epichlorohydrin (EPCH) was polymerized by using H₂SO₄ via cationic ring-opening mechanism. And then a novel RAFT-ROP agent was synthesized by the reaction of potassium ethyl xanthogenate and polyepichlorohydrin (poly-EPCH). By using the RAFT-ROP agent, poly[CL-b-EPCH-b-CL-(g-nBMA)] block-graft copolymers were synthesized. The principal parameters such as monomer concentration, initiator concentration, and polymerization time that affect the one-step polymerization reaction were evaluated. The block lengths of the block-graft copolymers were calculated by using ¹H-nuclear magnetic resonance (¹H NMR) spectrum. The block length could be adjusted by varying the monomer and initiator concentrations. The characterization of the products was achieved using ¹H NMR, Fourier-transform infrared spectroscopy, gel-permeation chromatography, thermogravimetric analysis, differential scanning calorimetry, elemental analysis, and fractional precipitation (γ) techniques. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2651–2659

Epichlorohydrin was polymerized by cationic ring-opening mechanism. A novel RAFT-ROP agent was synthesized by the reaction of potassium ethyl xanthogenate and polyepichorohydrin. A set of one-pot synthesis and RAFT and ROP polymerization conditions of the block-graft copolymers were evaluated. The proposed procedure for the preparation of block-graft copolymers is simple and efficient. The block length can be adjusted by varying the monomer and initiator concentrations

Direct arylation polymerization (DArP) is an emerging alternative to Stille and Suzuki polymerizations. This method is attractive as it allows preparation of high-molecular-weight conjugated polymers in good yield without the need to metallate monomers. Despite this promise, for poly(3-hexylthiophene) (P3HT) and related polymers that have β-protons on the thiophene ring, DArP is known to produce β-defects, which make the polymer properties different from polymers produced by traditional methods. Here, we demonstrate that DArP conditions based on simple, inexpensive, and bench-stable reagents can be tuned to limit the amount of defects and produce P3HT with properties remarkably similar to Stille P3HT. Specifically, lowering the reaction temperature, lowering the amount of catalyst, and using a bulkier carboxylate ligand is critical. Optimized conditions include reacting 2-bromo-3-hexylthiophene with 0.25 mol % of Pd(OAc)₂, 1.5 equivalents of K₂CO₃, and 0.3 equivalents of neodecanoic acid in N,N-dimethylacetamide at 70 °C and give DArP P3HT with ∼60% yield, regioregularity of 93.5%, molecular weight of 20 kDa, polydispersity of 2.8, and melting point of 217 °C, providing a very close match to Stille P3HT, which is obtained with 70–80% yield, 91–94% regioregularity, molecular weight of 15–25 kDa, polydispersity of 2.5–2.8, and melting point of 214–221 °C. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2660–2668

Direct arylation polymerization is known to produce β-defects in conjugated polymer chains. These defects make polymer properties different from polymers produced by methods such as Stille, Rieke, or GRIM. Here, for the case of poly(3-hexylthiophene) (P3HT), we demonstrate that DArP conditions can be tuned to control the amount of defects and produce P3HT with properties remarkably similar to those of Stille P3HT.

Terpolymers of ethylene, norbornene, and 5-exo norbornene methyl alcohol are prepared using Pd phosphine sulfonates as catalysts. The pendant hydroxyl groups are then transformed into thioacetate groups. Films cast from the resulting polymers are then oxidized by hydrogen peroxide. This green oxidation method is found to quantitatively transform thioacetate groups into sulfonic acids, leading to the formation of sulfonated hydrocarbon ionomers. These ionomers are thermally stable, exhibit increasing conductivity up to 110 °C, and have a low water uptake, indicating that these materials are potentially interesting candidates for the preparation of fuel cell membranes. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2669–2676

Palladium-catalyzed polymerization is used to prepare copolymers of ethylene and 5-exo norbornene methyl alcohol which are then transformed into polymers bearing thioacetate pendant groups. Using a green oxidation method which uses H₂O₂ as oxidant, sulfonated polymers can be prepared and processed as free standing films. These ionomers are thermally stable, have a low water uptake, and have increasing proton conductivities up to 110 °C, indicating that these materials are potentially interesting candidates for the preparation of fuel cell membranes.

pH- and temperature-responsive poly(N-isopropylacrylamide-block−4-vinylbenzoic acid) (poly(NIPAAm-b-VBA)) diblock copolymer brushes on silicon wafers have been successfully prepared by combining click reaction, single-electron transfer-living radical polymerization (SET-LRP), and reversible addition-fragmentation chain-transfer (RAFT) polymerization. Azide-terminated poly(NIPAAm) brushes were obtained by SET-LRP followed by reaction with sodium azide. A click reaction was utilized to exchange the azide end group of a poly(NIPAAm) brushes to form a surface-immobilized macro-RAFT agent, which was successfully chain extended via RAFT polymerization to produce poly(NIPAAm-b-VBA) brushes. The addition of sacrificial initiator and/or chain-transfer agent permitted the formation of well-defined diblock copolymer brushes and free polymer chains in solution. The free polymer chains were isolated and used to estimate the molecular weights and polydispersity index of chains attached to the surface. Ellipsometry, contact angle measurements, grazing angle-Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy were used to characterize the immobilization of initiator on the silicon wafer, poly(NIPAAm) brush formation via SET-LRP, click reaction, and poly(NIPAAm-b-VBA) brush formation via RAFT polymerization. The poly(NIPAAm-b-VBA) brushes demonstrate stimuli-responsive behavior with respect to pH and temperature. The swollen brush thickness of poly(NIPAAm-b-VBA) brush increases with increasing pH, and decreases with increasing temperature. These results can provide guidance for the design of smart materials based on copolymer brushes. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2677–2685

Stimuli-responsive poly(N-isopropylacrylamide-block−4-vinylbenzoic acid) brushes were synthesized by the combination of click reaction, single-electron transfer-living radical polymerization, reversible addition-fragmentation chain-transfer polymerization, and the grafting-from strategy.

A phenolic OH-containing benzoxazine (F-ap), which cannot be directly synthesized from the condensation of bisphenol F, aminophenol, and formaldehyde by traditional procedures, has been successfully prepared in our alternative synthetic approach. F-ap was prepared by three steps including (a) condensation of 4-aminophenol and 5,5'-methylenebis(2-hydroxybenzaldehyde) (1), (b) reduction of the resulting imine linkage by sodium borohydride, and (c) ring closure condensation by formaldehyde. The key starting material, (1), was prepared from 2-hydroxybenzaldehyde and s-trioxane in the presence of sulfuric acid. F-ap is structurally similar to bis(3,4-dihydro-2H-3-phenyl-1,3-benzoxazinyl)methane (F-a, a commercial benzoxazine based on bisphenol F/aniline/formaldehyde) except for two phenolic OHs. The phenolic OHs can provide reaction sites with epoxy and 1,1'-(methylenedi-p-phenylene)bismaleimide (BMI). The structure–property relationships between the thermosets of F-ap/epoxy, F-a/epoxy, F-ap/BMI, and F-a/BMI were discussed. Experimental data showed that thermosets based on F-ap/epoxy and F-ap/BMI provided much better thermal properties than those based on F-a/epoxy and F-a/BMI. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2686–2694

A phenolic OH-containing benzoxazine (F-ap), which cannot be directly synthesized from the condensation of bisphenol F, aminophenol, and formaldehyde by traditional procedures, has been successfully prepared in our alternative synthetic approach.

An imidazole-terminated hyperbranched polymer with octafunctional POSS branching units denoted as POSS-HYPAM-Im was prepared by the polymerization of excess amounts of tris(2-aminoethyl)amine with the first-generation methyl ester-terminated POSS-core poly(amidoamine)-typed dendrimer, reacting with methyl acrylate, and ester-amide exchange reaction with 3-aminopropylimidazole. The imidazole-terminated hyperbranched poly(amidoamine) denoted as HYPAM-Im was also synthesized with 1-(3-aminopropyl)imidazole from a methyl ester-terminated hyperbranched poly(amidoamine) by the ester-amide exchange reaction. The transmittance of the POSS-HYPAM-Im solution drastically decreased when the solution pH was greater than 8.2. On the other hand, the transmittance of the HYPAM-Im solution gradually decreased when the solution pH at 8.5 and was greater than 9. Spectrophotometric titrations of the hyperbranched polymer aqueous solutions with Cu²⁺ ions indicated the variation of the coordination modes of POSS-HYPAM-Im from the Cu²⁺–N₄ complex to the Cu²⁺–N₂O₂ complex and the existence of the only one complexation mode of Cu²⁺–N₄ between Cu²⁺ ion and HYPAM-Im with increasing the concentrations. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2695–2701

An imidazole-terminated hyperbranched polymer with octafunctional POSS branching units (POSS-HYPAM-Im) was prepared and their solution properties were studied. The transmittance of the POSS-HYPAM-Im solution drastically decreased when the solution pH was greater than 8.2. The coordination modes of POSS-HYPAM-Im shifted from the Cu²⁺–N₄ complex to the Cu²⁺–N₂O₂ complex through intermediate coordination states. These results suggest that the terminal function groups in POSS-HYPAM-Im are isolated and inhibit movement of associating with neighboring branches.

One-pot synthesis of thermoresponsive magnetic composite microspheres with a poly(N-isopropylacrylamide) (PNIPAM) shell and a Fe₃O₄ core is demonstrated. Temperature sensitivity of PNIPAM was adopted to design the novel synthesis pathway. The as-prepared composite microspheres have an obvious core-shell structure with a mean size of approximately 250 nm. The Fe₃O₄ core is approximately 5 nm and the thickness of the PNIPAM shell is approximately 10 nm. The content of Fe₃O₄ in the composite microspheres can be controlled by this method. The composite microspheres experience a swelling and shrinking process in water by adjusting the temperature below and above the lower critical solution temperature (LCST) around 32 °C. These microspheres also show fine response to an external magnetic field. This work presents a platform to synthesize organic/inorganic composite microspheres in a facile and efficient approach. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2702–2708

A novel one-pot synthesis of thermoresponsive magnetic nanoparticles in core-shell structure with the aid of temperature sensitivity of PNIPAM is presented.

High-performance and flexible poly(pyrrolone imide)s (PPyIs) were firstly prepared by the reaction of dianhydrides with an unsymmetric phosphinated triamine, 1-(3,4-diaminophenyl)-1-(4-aminophenyl)-1-(6-oxido-6H -dibenz <c,e> <1,2> oxaphosphorin-6-yl)ethane (1), which was prepared by a facile, one-pot procedure from the reaction DOPO, 4-aminoacetophenone in excess o-phenylenediamine in the presence of p-toluenesulfonic acid. Thermal properties of the resulting PPyIs were evaluated and compared with those of phosphinated polyimides with a similar structure. All of the prepared PPyIs films are tough and creasable. They display higher T_g (374–412 °C), lower coefficient of thermal expansion (34–46 ppm/°C), and better thermal stability (T_d 5 wt %: 456–477 °C, 800 °C char yield: 59–63%) than analogous phosphinated polyimides. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2709–2715

Generally, poly(pyrrolone imide)s (PPyIs) were prepared by copolymerizing tetraamine/diamine and dianhydride. In this work, we firstly prepared PPyIs by the reaction of dianhydrides with an unsymmetric phosphinated triamine, which was prepared by a facile, one-pot procedure. The resulting PPyIs are tough and creasable, and display higher Tg, dimensional stability, and thermal stability than those of phosphinated polyimides with a similar structure.

Radical copolymerization behavior of alkyl cyclobutenecarboxylate-derivatives 4-6 and related norbornene-derived compounds 7–9 is described. A variety of alkyl cyclobutenecarboxylates fused with cycloaliphatic framework (4–6) were prepared by [2 + 2] cycloaddition of five, six, and eight-membered cycloolefins with alkyl propiolates [alkyl = Me, 2-hydroxyethyl, and 3-γ-butyrolactonyl (γ-BL)]. The fused cyclobutenecarboxylates 4–6 were radically copolymerized with n-butyl acrylate (nBA) to afford random copolymers, and terpolymerized with alkyl methacrylates with bulky ester groups [alkyl = γ-BL and 3-(3-methyladamantyl)]. The cyclobutane-containing bicyclic framework incorporated in the resulting polymer backbone contributes to raising T_g of resulting copolymers. Similar results were obtained when a mixture of related norbornene-derived compounds were used as monomers with an apparently enhanced T_g-raising effect in the copolymerization with nBA. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2716–2724

Radical copolymerization behavior of alkyl cyclobutenecarboxylate-derivatives and related norbornene-derived compounds is described. A variety of alkyl cyclobutenecarboxylates fused with cycloaliphatic framework were radically copolymerized with nBA to afford random copolymers, and terpolymerized with alkyl methacrylates having bulky ester groups. Likewise, a mixture of related norbornene-derived compounds were copolymerized with alkyl (meth)acrylates to afford copolymers incorporating fused norbornane frameworks, which exhibited T_g-raising effect of the resulting copolymers.

Well-defined aromatic polyamide grafted with poly(tetrahydrofuran) [poly(THF)] was obtained by chain-growth condensation polymerization of 4-aminobenzoic acid ester macromonomers 1 bearing poly(THF) on the amino group. The macromonomers were easily prepared by reaction of living poly(THF) with 4-aminobenzoic acid ester. Polymerization of phenyl ester monomer 1a at −10 °C was accompanied with self-polycondensation, whereas that of methyl ester monomer 1b at 10 °C proceeded exclusively in a chain-growth polymerization manner.