Journal of Polymer Science Part A: Polymer Chemistry

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

15 January 2003

Volume 41, Issue 2

Pages 223–364

  1. Articles

    1. Top of page
    2. Articles
    1. Characterization and rheological properties of model alkali-soluble rheology modifiers synthesized by reversible addition–fragmentation chain-transfer polymerization (pages 223–235)

      E. Sprong, D. De Wet-Roos, M. P. Tonge and R. D. Sanderson

      Version of Record online: 3 DEC 2002 | DOI: 10.1002/pola.10503

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      Model conventional and associative alkali-soluble rheology modifiers were synthesized via reversible addition–fragmentation chain-transfer polymerization. The relationship between the rheological properties of the model alkali-soluble thickeners synthesized and the chain architecture and molar mass of the different rheology modifiers is dicussed.

    2. Determination of the cumulative degree of polymerization for the dead-end polymerization of styrene (pages 236–247)

      G. David, B. Boutevin and J. J. Robin

      Version of Record online: 3 DEC 2002 | DOI: 10.1002/pola.10569

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      The radical polymerization in dead-end polymerization conditions of styrene is investigated with 4,4′-azobiscyanovalericacid at 90 °C. The cumulative number-average degree of polymerization (DPn)cum was determined for several initial initiator and monomer concentration ratios (20% ≤ C0 ≤ 0.1%) by size exclusion chromatography. A new relation that joins (DPn)cum to experimental conditions was found [eq 1 is the relation of the (DPn)inst; (DPn)cum was obtained by iteration]. The image shows that our relation is correlated with experiments but not the (DPn)cum relation determined by Tobolsky.

    3. Polymerization of vinyl chloride with half-titanocene/methylaluminoxane catalysts (pages 248–256)

      Kiyoshi Endo and Makoto Saitoh

      Version of Record online: 3 DEC 2002 | DOI: 10.1002/pola.10574

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      The polymerization of vinyl chloride (VC) with half-titanocene/methylaluminoxane (MAO) catalysts is investigated. The polymerization of VC with the Cp*Ti(OCH3)3/MAO catalyst (Cp* = η5-pentamethylcyclopentadienyl) afforded high-molecular-weight poly(vinyl chloride) (PVC) in good yields. However, the polymer yields were low with the Cp*TiCl3/MAO catalyst. The optimum conditions of the MAO/Ti molar ratio and reaction temperature for the polymerization of VC with the Cp*Ti(OCH3)3/MAO catalyst were 10 and 20 °C, respectively. The polymer obtained with Cp*Ti(OCH3)3/MAO catalyst consisted of only regular head-to-tail units without any anomalous structure, whereas the Cp*Ti(OCH3)3/MAO catalyst gave the PVC-bearing anomalous units.

    4. Poly(silylenemethylene)-based polymer blends. III. Synthesis and properties of polymer blends containing siloxane-crosslinked poly(silylenemethylene)s (pages 257–263)

      Takuya Ogawa and Masashi Murakami

      Version of Record online: 4 DEC 2002 | DOI: 10.1002/pola.10575

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      Soft–hard binary polymer blends consisting of amorphous poly(silylenemethylene)s (PSMs) and crystalline poly(diphenylsilylene methylene) were prepared by both melt processing at 360 °C and in situ polymerization at 300 °C. Linear and siloxane-crosslinked PSMs were used as amorphous components for the purpose of determining how the crosslinks affected the interactions between the component polymers. Differential scanning calorimetry and dynamic mechanical analysis indirectly suggested that discernable differences between the blends containing linear and crosslinked PSMs were attributable to the degree of interactions between the amorphous and crystalline components.

    5. Polyelectrolyte complexes. V. Solid-state properties of some polycation/azo dye complexes controlled by the dye structure (pages 264–272)

      Stela Dragan and Daniel Timpu

      Version of Record online: 4 DEC 2002 | DOI: 10.1002/pola.10577

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      The solid-state properties of some polycation/azo dye complexes, with N,N-dimethyl-2-hydroxypropyleneammonium chloride (PCA5) units employed as polycations and with eight azo dyes (Crystal Scarlet, Congo Red, Crocein Scarlet MOO, Ponceau SS, Amaranth, Ponceau S, Direct Blue 1, and Direct Red 80), were studied. The physical properties of the PCA5/azo dye complexes (the complex stoichiometry, glass-transition temperature, and content of the crystalline phase) were controlled mainly by the dye structure but also by the polycation concentration and the presence of NaCl.

    6. Biodegradable brushlike graft polymers. I. Polymerization of ϵ-caprolactone onto water-soluble hydroxypropyl cellulose as the backbone by the protection of the trimethylsilyl group (pages 273–280)

      Caiqi Wang, Yuping Dong and Huimin Tan

      Version of Record online: 5 DEC 2002 | DOI: 10.1002/pola.10580

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      After the protection of partial hydroxyl groups with trimethylsilyl (TMS) groups, hydroxypropyl cellulose becomes soluble in organic solvents, and the number of hydroxyl groups as initiating groups can be controlled. As a result, a new brushlike graft poly(ϵ-caprolactone) can be prepared with hydroxypropyl cellulose as the backbone polymer by homogeneous ring-opening graft polymerization and deprotection. The protection and deprotection of the TMS group during the entire procedure were carefully monitored with Fourier transform infrared (FTIR) and NMR, and the final graft copolymers were characterized with FTIR, 1H NMR, 13C NMR, gel permeation chromatography, and differential scanning calorimetry.

    7. Cationic cyclopolymerization of new divinyl ethers: The effect of ether and ester neighboring functional groups on their cyclopolymerization tendency (pages 281–292)

      Md. Saifur Rahman, Tamotsu Hashimoto and Toshiyuki Kodaira

      Version of Record online: 6 DEC 2002 | DOI: 10.1002/pola.10572

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      The cationic polymerizations of two new divinyl ethers, 1-(2-vinyloxyethoxy)-2-[(2-vinyloxyethoxy)carbonyl]benzene (2) and 1,2-bis[(2-vinyloxyethoxy)carbonyl]benzene (3), as well as 1,2-bis(2-vinyloxyethoxy)benzene (1), were investigated with BF3OEt2 as an initiator and with the HCl/ZnCl2 initiating system in CH2Cl2 at 0 °C, and their cyclopolymerization tendency was found to be in the following order: 1 > 2 > 3. The differences in the cyclopolymerization tendencies among the divinyl ethers was explained by the differences in the solvation powers of their functional groups toward the active center: the ether oxygen of the ether group solvates intramolecularly with the active center to accelerate the intramolecular propagation, but such an interaction is less effective with the ester oxygen attached to the carbonyl group.

    8. Nickel- and palladium-catalyzed olefin polymerization under high pressures (pages 293–302)

      Noriyuki Suzuki, Jian Yu, Yuji Masubuchi, Akira Horiuchi and Yasuo Wakatsuki

      Version of Record online: 6 DEC 2002 | DOI: 10.1002/pola.10519

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      The polymerization of 1-hexene under high pressures (100–750 MPa) was investigated with nickel–α-diimine complex/methylaluminoxane and palladium–α-diimine complex/methylaluminoxane as catalyst systems. The catalytic activity of both the nickel and palladium complexes monotonously increased as pressure rose and became two to four times higher than that observed at atmospheric pressure. The pressure effects on the molecular weights depended greatly on the metal and monomer concentrations. The living-like character in the palladium-catalyzed polymerizations was somewhat emphasized under higher pressures. The nickel-catalyzed polymerizations under high pressures were not living, probably because the chain-transfer reaction was accelerated by high pressures.

    9. Synthesis and characterization of photocrosslinkable, side-chain, second-order nonlinear optical poly(ester imide)s with great film-forming ability and long-term dipole orientation stability (pages 303–312)

      Jiongxin Lu and Jie Yin

      Version of Record online: 6 DEC 2002 | DOI: 10.1002/pola.10579

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      A series of photocrosslinkable, side-chain, second-order nonlinear optical (NLO) poly(ester imide)s (PEIs) based on a chromophore-containing dianhydride, 2,2′-{4-[(4-nitrophenyl)-azo]phenyl}iminobis(ethyl benzene-1,2-dicarboxylic acid anhydride-4-carboxylate), benzophenone-3,3′,4,4′-tetracarboxylic dianhydride, and 4,4′-diamino-3,3′-dimethyl diphenylmethane were prepared. The resulting PEIs exhibited many useful physical characteristics, such as good organosolubility, excellent film-forming properties, high glass-transition temperatures (186–229 °C), and high thermal decomposition temperatures. The electrooptic coefficient value of PEI3 at 650 nm was 11.5 pm/V, and high long-term stability of the NLO chromophore alignment in the poled PEI3 film at 120 °C was observed. The temporal stability of the dipole orientation at 150 °C was further enhanced by ultraviolet irradiation because of photocrosslinking.

    10. Compositional and configurational sequence determination of methyl methacrylate/ethyl acrylate copolymers by one- and two-dimensional nuclear magnetic resonance spectroscopy (pages 313–326)

      A. S. Brar, Sunita Hooda and Rajeev Kumar

      Version of Record online: 9 DEC 2002 | DOI: 10.1002/pola.10581

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      The complete spectral assignments, in terms of the compositional and configurational sequences of the copolymers, were made with the help of distortionless enhancement by polarization transfer and two-dimensional heteronuclear single quantum coherence spectroscopy. The α-(CH3)M, [BOND]CH (E), [BOND]CH2, and 〉C[DOUBLE BOND]O carbons of both methyl methacrylate (M) and ethyl acrylate (E) units were found to be sensitive to various compositional and configurational sequences.

    11. Mechanism and kinetics of the imidazolidinone nitroxide-mediated free-radical polymerization of styrene (pages 327–334)

      Paul Dervan, Fawaz Aldabbagh, Per B. Zetterlund and Bunichiro Yamada

      Version of Record online: 9 DEC 2002 | DOI: 10.1002/pola.10582

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      We report the first polymerization of styrene initiated by low molecular weight polymeric alkoxyamines of imidazolidinone nitroxides. Experimentally obtained rate constants and equilibrium constants are used to interpret the mechanism of the polymerization process.

    12. Hydrogen-bonded thermotropic liquid-crystalline polyester–amides from bis(hydroxy alkamido)aranes: Synthesis and properties (pages 335–346)

      J. D. Sudha and C. K. S. Pillai

      Version of Record online: 9 DEC 2002 | DOI: 10.1002/pola.10576

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      Hydrogen-bonded aromatic–aliphatic polyester–amides (PEAs) were prepared by solution/melt polycondensation of aromatic–aliphatic amidodiols with terephthaloyl chloride/dimethyl terephthalate. The polymers exhibited liquid crystallinity with layered structures formed by self-organization of the hetero intermolecular hydrogen-bonded networks indicating smectic phases except for PEAs prepared from 1,4-bis(4-hydroxybutyramide)benzene (BHBB). The hydrogen atom of the phenyl-substituent group forces the neighboring carbonyl groups out of plane of the rings preventing formation of layered structures in the case of BHBB. The PEAs retained intermolecular hydrogen bonding even in the mesomorphic state, and variations in the hydrogen-bonded lamellae/micelles might be responsible for the variations from one smectic to another texture.

    13. Preparation and spectroscopic characterization of surface-enriched (with active sites) polymer-supported phase-transfer catalysts and their efficiency in organic addition reactions: A kinetic study (pages 347–364)

      T. Balakrishnan and E. Murugan

      Version of Record online: 9 DEC 2002 | DOI: 10.1002/pola.10562

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      Two batches of surface-enriched polymer-supported phase-transfer catalysts (SE-PSPTCs) with the same volume of the supporting monomers (St/DVB) and functional monomer (VBC) used in the conventional suspension copolymerization method were prepared, but with marginal changes in the experimental strategy; that is, the delayed introduction of VBC in the prepolymerized poly(St/DVB) led to the surface grafting of poly(VBC) onto poly(St/DVB) beads. As a result, when these beads were converted into catalysts by a treatment with triethylamine, there was effective quaternization, and so high concentrations of catalytic sites were available on the surfaces of the beads. The surface enrichment of the active sites on the poly(St/DVB) beads was confirmed by the chloride-ion concentration, Fourier transform infrared, scanning electron microscopy, EDAX, and ESCA. Furthermore, the catalytic efficiency of the conventional and SE-PSPTC catalysts were examined through the kinetics of dichlorocarbene addition to various olefins. The performance of the SE-PSPTCs was distinctly superior (twofold enhancement) to that of their conventional analogues.