Journal of Polymer Science Part A: Polymer Chemistry

Cover image for Journal of Polymer Science Part A: Polymer Chemistry

15 September 2005

Volume 43, Issue 18

Pages 4017–4322

  1. Articles

    1. Top of page
    2. Articles
    3. Rapid Communications
    4. Note
    1. Novel materials for bioanalytical and biomedical applications: Environmental response and binding/release capabilities of amphiphilic hydrogels with shape-persistent dendritic junctions (pages 4017–4029)

      Chao Zhu, Courtney Hard, Caiping Lin and Ivan Gitsov

      Article first published online: 26 JUL 2005 | DOI: 10.1002/pola.20898

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      The pH response of amphiphilic hydrogels containing poly (ethylene glycol) and poly(benzyl ether) dendrimers is investigated in an aqueous medium. The binding and release capabilities of networks of different crosslink densities, containing dendrimers of different generations, are evaluated with anionic pH indicators and cationic biological stains.

    2. Anionic copolymerization of styrenic-tipped macromonomers: A route to novel triblock–comb copolymers of styrene and isoprene (pages 4030–4039)

      Spiros Christodoulou, Hermis Iatrou, David J. Lohse and Nikos Hadjichristidis

      Article first published online: 26 JUL 2005 | DOI: 10.1002/pola.20890

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      The following triblock–comb copolymers of isoprene (I) and styrene (S)—PS-b-(PI-g-PI)-b-PS, PS-b-[PI-g-(PI-b-PS)]-b-PS, and (PS-g-PS)-b-(PI-g-PI)-b-(PS-g-PS) (where PS is polystyrene and PI is polyisoprene)—with PS contents of 20–30% were synthesized with high-vacuum techniques and the anionic copolymerization of styrenic-tipped macromonomers with I and S. The macromonomers, prepared by the end capping of living PI or PS with 4-(chlorodimethylsilyl) styrene, were used without isolation. Molecular characterization by size exclusion chromatography, size exclusion chromatography/two-angle laser light scattering, and NMR spectroscopy indicated that the triblock–comb copolymers had high molecular and compositional homogeneity.

    3. Novel block–comb/graft copolymers with the macromonomer strategy and anionic polymerization (pages 4040–4049)

      Giorgos Koutalas, David J. Lohse and Nikos Hadjichristidis

      Article first published online: 26 JUL 2005 | DOI: 10.1002/pola.20891

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      The macromonomer technique, in combination with anionic copolymerization, is proved to be a powerful method for the synthesis of block grafts (ABA, AB, ABC, and ABCBA, where one or all blocks are combs or grafts) and miktoarm stars (A2B, where B is a comb). All the products, characterized by size exclusion chromatography/two-angle laser light scattering, indicated high homogeneity. Following similar procedures and altering the combination of monomers can lead to the synthesis of a large number of different architectures based on comb and graft polymers.

    4. Properties of acrylic–polyurethane hybrid emulsions synthesized by the semibatch emulsion copolymerization of acrylates using different polyurethane particles (pages 4050–4069)

      Urška Šebenik and Matjaž Krajnc

      Article first published online: 29 JUL 2005 | DOI: 10.1002/pola.20896

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      Aqueous acrylic–polyurethane hybrid emulsions were prepared by the semibatch emulsion copolymerization of methyl methacrylate and butyl acrylate in the presence of eight polyurethane dispersions. The polyurethane dispersions were synthesized with isophorone diisocyanate, different polyols, butanediol, and dimethylol propionic acid. The effect of the use of different polyurethane seed particles and the effect of different weight ratios of methyl methacrylate to butyl acrylate on the emulsion properties, microphase structure, and mechanical properties of hybrid films was investigated. The interactions between the acrylic and polyurethane components in hybrid particles were studied.

    5. Anionic homo- and copolymerization of double-tailed macromonomers: A route to novel macromolecular architectures (pages 4070–4078)

      Paraskevi Driva, Hermis Iatrou, David J. Lohse and Nikos Hadjichristidis

      Article first published online: 29 JUL 2005 | DOI: 10.1002/pola.20895

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      The synthesis of model linear and star double-comb polybutadienes (PBds), as well as molecular double-brush PBds, is described. The synthetic approach involves the synthesis of a styrenic double-tailed macromonomer, followed by in situ homo- or copolymerization with butadiene. The star double comb was synthesized by the reaction of living double-comb PBd with trichloromethylsilane. Characterization carried out by size exclusion chromatography, with differential refractometer and light scattering detectors, indicated that the synthesized PBds had a high degree of molecular and structural homogeneity.

    6. Synthesis of zinc glutarates with various morphologies using an amphiphilic template and their catalytic activities in the copolymerization of carbon dioxide and propylene oxide (pages 4079–4088)

      Jong-Seong Kim, Hyunchul Kim, Jihwan Yoon, Kyuyoung Heo and Moonhor Ree

      Article first published online: 27 JUL 2005 | DOI: 10.1002/pola.20905

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      Zinc glutarate (ZnGA) catalysts in various shapes were synthesized in solvent systems of various polarities from zinc acetate dihydrate and glutaric acid with and without the aid of an amphiphilic block copolymer template. The presence of the template and the polarity of the solvent significantly affected the morphology, particle size, surface area, and crystallinity of the resulting catalyst. However, all the catalysts had the same crystal lattice unit cell structure and similar surface compositions. All these characteristics of the catalysts influenced the ZnGA-catalyzed copolymerization of carbon dioxide and propylene oxide. The catalytic activities of the catalysts in this copolymerization depended primarily on their surface area and secondarily on their crystallinity; a larger surface area and a higher crystallinity resulted in higher catalytic activity.

    7. Antimicrobial polymers containing melamine derivatives. II. Biocidal polymers derived from 2-vinyl-4,6-diamino-1,3,5-triazine (pages 4089–4098)

      Zhaobin Chen and Yuyu Sun

      Article first published online: 27 JUL 2005 | DOI: 10.1002/pola.20906

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      A polymerizable melamine derivative, 2-vinyl-4,6-diamino-1,3,5-triazine (VDAT), was smoothly homopolymerized and copolymerized with styrene through conventional free-radical polymerizations. Upon chlorine bleach treatment, chloromelamine structures were formed in the VDAT-containing polymeric materials. The polymeric chloromelamines demonstrated powerful, durable, and rechargeable antimicrobial functions against multidrug-resistant Gram-negative and Gram-positive bacteria, and this suggests that copolymerization with VDAT can be an effective approach to turn ordinary polymers into antimicrobial materials.

    8. Densely grafting copolymers of ethyl cellulose through atom transfer radical polymerization (pages 4099–4108)

      Dawa Shen, Hui Yu and Yong Huang

      Article first published online: 27 JUL 2005 | DOI: 10.1002/pola.20908

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      Densely grafting copolymers of ethyl cellulose with polystyrene and poly(methyl methacrylate) were synthesized through atom transfer radical polymerization. The molecular weight of the graft copolymers increased without any trace of the macroinitiator, and the polydispersity was low. The molecular weight of the side chains increased with the monomer conversion. A kinetic study indicated that the polymerization was first-order. The morphology of the densely grafted copolymer in solution was characterized through laser light scattering. The individual densely grafted copolymer molecules were observed through atomic force microscopy, which confirmed the synthesis of the densely grafted copolymer.

    9. Synthesis of well-defined aromatic polyesters by chain-growth polycondensation under suppression of transesterification (pages 4109–4117)

      Ken-ichi Iwashita, Akihiro Yokoyama and Tsutomu Yokozawa

      Article first published online: 29 JUL 2005 | DOI: 10.1002/pola.20907

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      The chain-growth polycondensation of active amide derivatives of 4-hydroxybenzoic acid, 1a and 1b, was investigated. The reaction conditions were examined to suppress the transesterification of the polymer backbone with the monomer. Under the optimized conditions, a diblock copolymer of 1a and 1b was synthesized.

    10. Polymerization of 1,2:5,6-diepithio-3,4-di-O-methyl-D-mannitol, 1,2:5,6-diepithio-3,4-di-O-methyl-L-iditol, and 1,2:5,6-diepithio-3,4-di-O-methyl-allitol using zinc complexes: The regio- and stereoselectivities and asymmetric synthesis of thiosugar polymers (pages 4118–4125)

      Toshifumi Satoh, Tomoko Imai, Norihiko Sugie, Hisaho Hashimoto and Toyoji Kakuchi

      Article first published online: 27 JUL 2005 | DOI: 10.1002/pola.20904

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      The polymerizations of 1,2:5,6-diepithio-3,4-di-O-methyl-D-mannitol (1a), 1,2:5,6-diepithio-3,4-di-O-methyl-L-iditol (1b), and 1,2:5,6-diepithio-3,4-di-O-methyl-allitol (1c) were carried out with zinc complexes. The polymerization of 1a using the ZnEt2/H2O (1/1) catalyst in tetrahydrofuran proceeded through a regio- and stereoselective cyclopolymerization mechanism to produce thiosugar polymers mainly consisting of 2,5-anhydro-1,5-dithio-3,4-di-O-methyl-D-glucitol units. The polymers obtained from 1b and 1c with ZnEt2/H2O exhibited lower stereoregularities than that from 1a. On the other hand, the polymerization of 1c using ZnEt2/(R or S)-BN asymmetrically proceeded, and optically active polymers consisting of desulfurized acyclic units were obtained. When ZnEt2/(R)-BN (1/1) in toluene was used, the polymer with [α]D23 = +56.9° was obtained.

    11. Synthesis of well-defined polymers end-functionalized with crosslinkable aziridine groups by living anionic polymerization (pages 4126–4135)

      Mamoru Kobayashi, Kentaro Uchino and Takashi Ishizone

      Article first published online: 27 JUL 2005 | DOI: 10.1002/pola.20777

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      Well-defined end-functionalized polystyrene, poly(α-methylstyrene), and polyisoprene with cationically polymerizable aziridine groups were synthesized by the termination reactions of the anionic living polymers of styrene, α-methylstyrene, and isoprene with 1-[2-(4-chlorobutoxy)ethyl]aziridine in tetrahydrofuran at −78 °C.

    12. Synthesis and properties of a bisphenol A based phthalonitrile resin (pages 4136–4143)

      Matthew Laskoski, Dawn D. Dominguez and Teddy M. Keller

      Article first published online: 29 JUL 2005 | DOI: 10.1002/pola.20901

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      A multiple aromatic ether linked phthalonitrile monomer was synthesized, characterized, and converted thermally to a thermosetting polymer. The oligomeric monomer was prepared from the reaction of an excess amount of bisphenol A with 4,4′-difluorobenzophenone in the presence of K2CO3 in an N,N-dimethylformamide/toluene solvent mixture, followed by end capping with 4-nitrophthalonitrile in a two-step, one-pot reaction. Upon curing to a thermoset, the oligomeric phthalonitrile polymer exhibited excellent thermooxidative stability, maintained good structural integrity at elevated temperatures, and showed low water absorption under ambient conditions.

    13. Fluorinated alcohols as surface-active agents in cationic photopolymerization of epoxy monomers (pages 4144–4150)

      M. Sangermano, R. Bongiovanni, A. Priola and D. Pospiech

      Article first published online: 1 AUG 2005 | DOI: 10.1002/pola.20865

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      The use of fluorinated alcohols as surface modifying agents through a chain transfer mechanism in cationic photopolymerization of epoxy system is reported. A surface modification of the photocured films is achieved in the presence of very low amount of fluoro additive.

    14. Automated parallel anionic polymerizations: Enhancing the possibilities of a widely used technique in polymer synthesis (pages 4151–4160)

      Carlos Guerrero-Sanchez, Caroline Abeln and Ulrich S. Schubert

      Article first published online: 4 AUG 2005 | DOI: 10.1002/pola.20887

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      Automated parallel anionic polymerization experiments have been successfully performed in a commercial automated synthesizer robot. This experimental technique enables detailed and fast kinetic studies of the anionic polymerization process to be performed. The synthesis of well-defined block copolymers is also possible in an automated fashion. This high-throughput approach can become a valuable experimental tool for the fast and systematic synthesis of well-defined polymers and for gaining better insight into the complex anionic polymerization process.

    15. PAN composite membrane with different solvent affinities controlled by surface modification methods (pages 4161–4171)

      Ecaterina Stela Dragan, Marcela Mihai, J. Schauer and Luminita Ghimici

      Article first published online: 4 AUG 2005 | DOI: 10.1002/pola.20869

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      PAN composite membranes with surface properties designed by either a chemical modification with ethylenediamine (EDA) or layer-by-layer (LbL) polyelectrolyte adsorption were investigated in this paper. The adsorbed polyion amount was controlled by the nature and concentration of the supporting electrolyte in polyion deposition solution. The swelling degree in pure alcohols of the LbL modified PAN composite membrane decreased with the increase of the solvent polarity and with the decrease of the pore volume by pore filling with polyelectrolyte complex multiplayer.

    16. Alternating copolymerization of carbon dioxide and epoxide catalyzed by an aluminum Schiff base–ammonium salt system (pages 4172–4186)

      Hiroshi Sugimoto, Hiroaki Ohtsuka and Shohei Inoue

      Article first published online: 1 AUG 2005 | DOI: 10.1002/pola.20894

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      The alternating copolymerization of carbon dioxide (CO2) and epoxide with an aluminum Schiff base complex in conjunction with an appropriate additive as a novel initiator is demonstrated. Typically, the copolymerization of CO2 and cyclohexene oxide took place smoothly under CO2 (50 atm) at 80 °C in CH2Cl2 and gave an alternating copolymer with a narrow molecular weight distribution in a high yield in 24 h.

    17. Influence of aggregate formation in the copolymerization of ethyl α-hydroxymethylacrylate with methyl methacrylate (pages 4187–4195)

      R. Cuervo-Rodríguez, R. París-Escribano, M. C. Fernández-Monreal, E. L. Madruga and M. Fernández-García

      Article first published online: 1 AUG 2005 | DOI: 10.1002/pola.20819

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      The free-radical copolymerization of ethyl α-hydroxymethylacrylate (EHMA) with methyl methacrylate (MMA) was carried out in chlorobenzene and 1,4-dioxane solutions at 50 °C. Although the copolymer composition was well described by the Mayo–Lewis terminal model, the copolymerization rate was not. The experimental data were well explained by the implicit penultimate effect model when rE × rM was equal to sE × sM. The differences observed for the EHMA–MMA system with the reaction medium were the results of the electronic effects of additional β-oxygen atoms and intramolecular and intermolecular interactions through hydrogen bonding.

    18. Methylated and pegylated PLA–PCL–PLA block copolymers via the chemical modification of di-hydroxy PCL combined with the ring opening polymerization of lactide (pages 4196–4205)

      Ming-Hsi Huang, Jean Coudane, Suming Li and Michel Vert

      Article first published online: 1 AUG 2005 | DOI: 10.1002/pola.20870

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      Methylated and pegylated poly(lactide)-block-poly(ε-caprolactone)-block-poly(lactide) copolymers, were prepared in three steps: combining the formation of carbanion-bearing dihydroxylated-PCL, the coupling of iodomethane or bromoacetylated α-hydroxyl-ω-methoxy-poly(ethylene glycol) onto the carbanionic PCL, and finally the ring opening polymerization of DL-lactide initiated by the preformed grafted diOH-PCL copolymers. Some properties of the resulting block copolymers were investigated, especially the degradation of the grafted copolymers in the presence of Pseudomonas cepacia lipase, and it is shown that the presence of the grafted substituents inhibited the enzymatic degradation of PCL segments.

    19. High-molecular-weight poly(1,5-dioxepan-2-one) via enzyme-catalyzed ring-opening polymerization (pages 4206–4216)

      Rajiv K. Srivastava and Ann-Christine Albertsson

      Article first published online: 4 AUG 2005 | DOI: 10.1002/pola.20888

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      Enzymatic ring-opening polymerization of 1,5-dioxepan-2-one (DXO) was performed with lipase CA as a biocatalyst. The polymerization has the characteristics of living polymerization. An initial activation via heating the enzyme to 60 °C was sufficient to start the polymerization. Effect of water, temperature, and amount of enzyme on monomer conversion and polymer molecular weight was evaluated. PDXO having Mn = 56,000 g/mol and Mw = 112,000 g/mol was obtained by polymerization with 10 wt% lipase (with respect to monomer) at 60 °C for 4 h. The rate of polymerization of DXO with lipase was faster than that of ε-caprolactone under identical reaction conditions.

    20. Melt amination of polypropylenes (pages 4217–4232)

      Q.-W. Lu, C. W. Macosko and J. Horrion

      Article first published online: 3 AUG 2005 | DOI: 10.1002/pola.20899

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      Amine (primary and secondary) functionalized polypropylenes were prepared by the melt blending of maleated polypropylenes with small diamines, including hexamethylenediamine (primary–primary diamine), p-xylylenediamine (primary–primary diamine), and N-hexylethylenediamine (primary–secondary diamine), at various diamine/anhydride molar ratios in a batch mixer and a twin-screw extruder. The experimental conversion data by Fourier transform infrared nearly agreed with the assumption of a complete reaction between the primary amine and anhydride. Chain extensions of the maleated polypropylenes by the diamines were monitored by the torques during mixing and further evaluated by rheological (dynamic shear rheometry) and mechanical measurements. We show that these amino polypropylenes are very effective adhesion promoters and compatibilizers of thermoplastic polyurethanes with polypropylene.

    21. Novel active ester-bridged copolynorbornene materials containing terminal functional hydroxyl, amino, methacryloyl, or ammonium groups via ring-opening metathesis polymerization (pages 4233–4247)

      Der-Jang Liaw, Tsang-Pin Chen and Ching-Cheng Huang

      Article first published online: 3 AUG 2005 | DOI: 10.1002/pola.20766

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      Several random and block copolynorbornenes with side chains containing terminal hydroxyl, amino, methacryloyl or ammonium groups were derived from the functional alkyl ester-containing norbornenes by ring-opening metathesis polymerization (ROMP). The main chain of ROMP-type polynorbornene played a more important role for Tg in comparison with vinyl addition polymerization. There is little effect on Tg (about −39 °C) of polynorbornenes with different length of alkyl side chain. These polymeric materials with various functional groups or amphiphilic architectures are accessible by ROMP, whose topology makes them particularly attractive for application potential such as biomedical and photoelectric materials.

    22. Ethylene and propylene polymerization with bis(indenyl)zirconium/Mao catalytic systems modified by sterically demanding alcohols (pages 4248–4259)

      Caio L. Firme, Andrei V. Grafov and Marcos L. Dias

      Article first published online: 3 AUG 2005 | DOI: 10.1002/pola.20839

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      Ethylene and propylene polymerization using Ind2ZrCl2 and Ind2Zr(CH3)2/MAO catalytic systems modified by the sterically demanding bridged alicyclic alcohols, adamantan-1-ol, adamantan-2-ol, 2-methyladamantan-2-ol, and fenchyl alcohol, was investigated. Lower alcohols like isopropanol completely deactivate the system, whereas in the case of catalysts modified by these voluminous alcohols only a slight decrease in the catalytic activity proportional to alcohol/metallocene molar ratio was observed. The addition of the modifiers gives rise to polymers with higher molecular weights than the nonmodified systems, but no structural changes in the polyethylenes were observed. The addition of the sterically demanding alcohols to the reaction medium changes the regioregularity of polypropylenes, but does not significantly influence their stereoregularity, at 30 °C. Propylene–ethylene copolymers containing up to 8.6% of ethylene units derived from 1,3-insertion and significant amount of rr-centered pentads were obtained by single-monomer polymerization of propylene with Ind2ZrCl2/MMAO/adamantan-1-ol, at 70 °C.

    23. Novel thermally latent self-crosslinkable copolymers bearing oxetane and hemiacetal ester moieties: The synthesis, self-crosslinking behavior, and thermal properties (pages 4260–4270)

      Hiroyuki Komatsu, Tetsuo Hino and Takeshi Endo

      Article first published online: 3 AUG 2005 | DOI: 10.1002/pola.20910

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      Novel thermally latent self-crosslinkable copolymers containing hemiacetal ester and oxetane moieties were synthesized by the radical copolymerizations of 1-propoxyethyl methacrylate, 3-ethyl-3-methacryloyloxymethyl oxetane, and/or n-butyl methacrylate at 60 °C in the presence of 2,2′-azoisobutyronitrile as an initiator. The obtained copolymers showed good solubility for common organic solvents. The thermal crosslinking behaviors were examined with several Lewis acid catalysts. In particular, the treatment with aluminum-2-ethylhexanate triethanolamine at 160 °C was found to efficiently yield the corresponding self-crosslinked polymers.

    24. Synthesis of well-defined AB20-type star polymers with cyclodextrin-core by combination of NMP and ATRP (pages 4271–4279)

      Yutaka Miura, Atsushi Narumi, Soh Matsuya, Toshifumi Satoh, Qian Duan, Harumi Kaga and Toyoji Kakuchi

      Article first published online: 4 AUG 2005 | DOI: 10.1002/pola.20837

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      The synthesis of an AB20-type heteroarm star polymer consisting of a polystyrene arm and 20-arms of poly(methyl methacrylate) or poly(tert-butyl acrylate) was carried out using the combination of nitroxide-mediated polymerization and atom transfer radical polymerization. The NMP of styrene was carried out using mono-6-[4-(1′-(2″,2″,6″,6″-tetramethyl-1″-piperidinyloxy)-ethyl)benzamido]-β-cyclodextrin peracetate (1) to afford end-functionalized polystyrene with an acetylated β-cyclodextrin (β-CyD) unit prepolymer 2 with a number-average molecular weight (Mn) of 11,700 and a polydispersity (Mw/Mn) of 1.17. After deacetylation of prepolymer 2, the resulting polymer was reacted with 2-bromoisobutyric anhydride to give end-functionalized polystyrene with 20(2-bromoisobutyrol)s β-CyD, macroinitiator 4. The copper (I)-mediated ATRP of methyl methacrylate and tert-butyl acrylate was carried out using macroinitiator 4. The resulting polymers were isolated by SEC fractionation to produce AB20-type star polymers with a β-CyD-core, 5. The well-defined structure of 5 with weight-average molecular weight (Mw)s of 13,500–65,300 and Mw/Mn's of 1.26–1.28 was demonstrated by SEC and light scattering measurements. The arm polymers were separated from 5 by destruction with 28 wt % sodium methoxide in order to analyze the details of their characteristic structure.

    25. Synthesis and characterization of a new acceptor (n-type) fluorinated and terminal-functionalized polythiophene (pages 4280–4287)

      Shanneth Thomas, Cheng Zhang and Sam-Shajing Sun

      Article first published online: 4 AUG 2005 | DOI: 10.1002/pola.20877

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      Fluorinated polythiophenes are very attractive for optoelectronic applications because of the presence of fluorine, which can withdraw electrons and also improve polymer chemical stability. A new monosubstituted thiophene monomer consisting of a fluorinated ester group was synthesized from 3-thiophene carboxylic acid and n-heptafluorobutanol. This group was expected to facilitate the acceptor properties of the polymer. The synthesis of an n-type fluorinated terminal-end functionalized polythiophene was accomplished with the Ullmann coupling reaction. A polymer soluble in tetrahydrofuran was obtained with a molecular weight of approximately 15,000 g/mol. In solution, it exhibited a band gap of 2.4 eV, and the photoluminescent excitation and emission maxima were 370 nm and 555 nm, respectively. All peaks were bathochromically shifted when they were measured in the solid state.

  2. Rapid Communications

    1. Top of page
    2. Articles
    3. Rapid Communications
    4. Note
    1. Instant living cationic polymerization using SnCl4/EtAlCl2 with a weak Lewis base: Ultrafast polymerization in seconds (pages 4288–4291)

      Tomohide Yoshida, Arihiro Kanazawa, Shokyoku Kanaoka and Sadahito Aoshima

      Article first published online: 4 AUG 2005 | DOI: 10.1002/pola.20902

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      The living cationic polymerization of isobutyl vinyl ether in 1–2 s is demonstrated with SnCl4 and EtAlCl2 in the presence of a weak base, ethyl chloroacetate, at subzero temperatures. The reaction proceeds 105 times faster than the reaction with conventional EtAlCl2 systems in the presence of a stronger base such as ethyl acetate at 0 °C yet remains highly controlled, yielding polymers with the near theoretical number-average molecular weight and with narrow molecular weight distributions (weight-average molecular weight/number-average molecular weight = 1.03). Two Lewis acids play different important roles in this system: EtAlCl2 generates initiating species quantitatively from an adduct of isobutyl vinyl ether and acetic acid, whereas SnCl4 promotes rapid polymerization.

    2. Photosensitive copolymers with various types of azobenzene side groups synthesized by living cationic polymerization (pages 4292–4297)

      Tomohide Yoshida, Shokyoku Kanaoka and Sadahito Aoshima

      Article first published online: 5 AUG 2005 | DOI: 10.1002/pola.20892

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      Well-defined photoresponsive polymers of vinyl ethers with various azo side groups were synthesized via living cationic copolymerization using Et1.5AlCl1.5 in the presence of an ester as an added base. Despite the apparently undesirable structures, too basic or bulky, of azo-containing monomers for cationic polymerization, all copolymerizations with an alkyl vinyl ether proceeded with livingness to yield the product polymers with extremely narrow MWDs (Mw/Mn = 1.06−1.13). It should be noted that living polymers were produced even from a monomer with the dimethylamino group. The different azo groups in the product copolymers permitted reversible photo-responsive isomerization at a specific wavelength related to the structure of the azo group.

    3. Electrochemical polymerization of 3,4-ethylenedioxythiophene in a DNA liquid-crystal electrolyte (pages 4298–4302)

      Hiromasa Goto, Nobuhiko Nomura and Kazuo Akagi

      Article first published online: 5 AUG 2005 | DOI: 10.1002/pola.20909

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      A composite film of optically active poly(3,4-ethylenedioxythiophene) was prepared by electrochemical polymerization in double-stranded DNA as a chiral nematic liquid-crystal field. The polymer film showed a Cotton effect in a circular dichroism spectrum, and it also showed honeycomb morphologies in a scanning electron microscopy image. The chirality of the polymer during the polymerization was preserved even after rigorous washing. The insolubility and infusibility of the polymer film were indispensable for preserving the metastable chiral structure.

  3. Note

    1. Top of page
    2. Articles
    3. Rapid Communications
    4. Note
    1. You have free access to this content
      Synthesis of maleimide-terminated n-butyl acrylate oligomers by atom transfer radical polymerization: Study of their copolymerization with vinyl ethers (pages 4303–4322)

      Cyrille Boyer, Belkacem Otazaghine, Bernard Boutevin, Christine Joly-Duhamel and Jean-Jacques Robin

      Article first published online: 5 AUG 2005 | DOI: 10.1002/pola.20878

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      New maleimide-terminated oligomers of n-butyl acrylate can be synthesized by atom transfer radical polymerization, using functional initiators. The oligomers have been synthesized using protected aromatic or aliphatic amines. The amine-terminated oligomers have been converted into the corresponding maleimide ones. The copolymerization of the maleimide compounds with vinyl ethers has been investigated, and the comparison of the kinetics of photopolymerization of aliphatic maleimides or aromatic ones with divinyl ethers shows the higher reactivity of the former. The acceptor/donor complex homopolymerization mechanism has been enlightened.

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