Journal of Polymer Science Part A: Polymer Chemistry

Cover image for Vol. 42 Issue 3

Special Issue: Macromolecules in the 21st Century—Otto Vogl

1 February 2004

Volume 42, Issue 3

Pages 387–818

Issue edited by: E. Borsig, P. Hrdlovič

  1. Foreword

    1. Top of page
    2. Foreword
    3. Miscellaneous
    4. Articles
    1. You have free access to this content
      Foreword (pages 387–388)

      Eberhard Borsig and Pavol Hrdlovič

      Version of Record online: 11 DEC 2003 | DOI: 10.1002/pola.11085

  2. Miscellaneous

    1. Top of page
    2. Foreword
    3. Miscellaneous
    4. Articles
    1. You have free access to this content
      Otto Vogl from '74 to 75 (pages 389–390)

      David A. Tirrell

      Version of Record online: 11 DEC 2003 | DOI: 10.1002/pola.11086

  3. Articles

    1. Top of page
    2. Foreword
    3. Miscellaneous
    4. Articles
    1. The discovery of isotactic polypropylene and its impact on pure and applied science (pages 391–395)

      Paolo Corradini

      Version of Record online: 11 DEC 2003 | DOI: 10.1002/pola.10857

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      Crystalline polymers of propylene were obtained for the first time by Giulio Natta and his research group in March 1954, with metallorganic catalysts (now called Ziegler–Natta catalysts). By the end of the year, the peculiar isotactic configuration of the polymer molecules was established. The researcher recalls the events that brought the synthesis and structural characterization of many different stereoregular polymers in a very short time. Previously, stereoregular polymers were a monopoly of nature. Natta got the Nobel Prize in Chemistry with Ziegler in 1963. Because of its excellent properties, in less than 50 years from its discovery, the industrial production of crystalline isotactic polypropylene has reached more than 30 million tons per year in the world.

    2. Polyolefins: The most promising large-volume materials for the 21st century (pages 396–415)

      P. Galli and G. Vecellio

      Version of Record online: 18 DEC 2003 | DOI: 10.1002/pola.10804

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      This manuscript discusses the evolution of polyolefins, the most promising large-volume polymer materials for the 21st century.

    3. Uniform polymer in synthetic polymer chemistry (pages 416–431)

      Koichi Hatada, Tatsuki Kitayama, Koichi Ute and Takafumi Nishiura

      Version of Record online: 11 DEC 2003 | DOI: 10.1002/pola.10846

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      A uniform polymer is a polymer composed of molecules uniform with respect to their molecular weight and constitution. Natural polymers such as nucleic acids and polypeptides are known to be uniform with respect to their molecular weight, sequence arrangement, stereoregularity, and conformation. However, synthetic polymers are usually nonuniform. A typical method for the preparation of synthetic uniform polymers is a combination of living polymerization and supercritical fluid chromatography separation. End-functionalized uniform polymers enable us to prepare uniform polymer architectures such as block, graft, comb, and star polymers. The preparation of these synthetic uniform polymers and their use for understanding fundamental problems in polymer chemistry are described.

    4. Simultaneous introduction of phosphonic and carboxylic acid functions to hydroxylated macromolecules (pages 432–443)

      Stanislaw Penczek, Julia Pretula and Krzysztof Kaluzynski

      Version of Record online: 11 DEC 2003 | DOI: 10.1002/pola.10907

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      A general method of introducing into multihydroxy macromolecules phosphonic and carboxylic functions at the same carbon atom was investigated. As an example, a dihydrophilic ionic–nonionic block copolymer of ethylene oxide and glycidol was used.

    5. New functionalized polyesters to achieve controlled architectures (pages 444–452)

      Anna Finne and Ann-Christine Albertsson

      Version of Record online: 11 DEC 2003 | DOI: 10.1002/pola.10805

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      The need for advanced materials with specific properties is increasing, and so it is essential to design new specialized polymers with usable functionalities and controlled properties. The presence of functional groups in a polymer backbone provides sites for chemical modification, and through a variation in the structure, the physical properties of the polymers can be affected. In this study, the incorporation of a double bond into the backbone of poly(ϵ-caprolactone) was compared with the analogous reaction for poly(L-lactide). Furthermore, the incorporated C[DOUBLE BOND]C double bond in poly(L-lactide) was oxidized into epoxides with good yields and without any side reactions.

    6. Design of lactide copolymers as biomaterials (pages 453–462)

      Tatsuro Ouchi and Yuichi Ohya

      Version of Record online: 12 DEC 2003 | DOI: 10.1002/pola.10848

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      The synthetic methods and properties of the following novel lactide copolymers are reported: (1) random and block copolymers of depsipeptide and L-lactide with reactive (ionic) side-chain groups, (2) comb-type poly(L-lactide) (PLA) and branched PLA, and (3) PLA-grafted polysaccharide and PLA with terminal saccharide residues. Poly(depsipeptide-random-L-lactide)s and polydepsipeptide-block-poly(L-lactide)s with reactive (ionic) side-chain groups should be useful for the preparation of matrices and microspheres with reactive surfaces because of their amphiphilic structures. Comb-type PLA and branched PLA show lower crystallinities than linear PLA. PLA-grafted polysaccharide should be useful for the preparation of matrices with various microstructures and mechanical and degradation properties through the introduction of hydrophilic segments.

    7. Controlling the water content of never dried and reswollen bacterial cellulose by the addition of water-soluble polymers to the culture medium (pages 463–470)

      Marit Seifert, Stephanie Hesse, Vasken Kabrelian and Dieter Klemm

      Version of Record online: 12 DEC 2003 | DOI: 10.1002/pola.10862

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      Bacterial cellulose (BC) fleeces of Acetobacter xylinum have been produced in the presence of carboxymethylcellulose (CMC), methylcellulose (MC), and poly(vinyl alcohol) (PVA), respectively, in the Hestrin-Schramm culture medium. In the case of CMC and MC, a porelike cellulose network structure forms, increasing the water retention ability (expressed as the water content) in comparison with standard BC in never dried and reswollen states. The water content in BC can be reduced by the addition of PVA to the culture medium.

    8. Life—a complex polymer system (pages 471–478)

      Josef Schurz

      Version of Record online: 12 DEC 2003 | DOI: 10.1002/pola.10875

      System theory is a new paradigm in epistemology for understanding and describing nature. It has been very successfully applied for the study of living organisms, which represent complex systems made up essentially of high polymer molecules. The concerted and synchronized interaction of their components creates the phenomenon of life as an emergent system property. Living systems are open to the environment and exchange matter, energy, and information. They operate according to system laws, which are based on but not identical with natural laws. Systems can be described by their conditions, states, properties, and behavior. System theory can be readily generalized and applied to different fields such as engineering, sociology, psychology, ecology, and economy.

    9. Biopolymers for biocatalysis: Structure and catalytic mechanism of hydroxynitrile lyases (pages 479–486)

      Karl Gruber and Christoph Kratky

      Version of Record online: 15 DEC 2003 | DOI: 10.1002/pola.10845

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      Hydroxynitrile lyases (HNLs) catalyze the reversible cleavage of α-cyanohydrins to yield hydrocyanic acid and the corresponding aldehyde or ketone. Besides its biological interest, this class of enzymes is also of relevance in industrial biocatalysis for the enantioselective condensation of HCN with a variety of aldehydes and ketones. Several distinctly different types of HNLs are known, which must have originated through convergent evolution from different ancestral proteins. Three-dimensional structural data are known for three classes of HNLs. Insights into the reaction mechanisms emerged from a combination of structural, enzyme kinetic, spectroscopic, and molecular modeling data.

    10. Cellulose structure and biosynthesis: What is in store for the 21st century? (pages 487–495)

      R. Malcolm Brown Jr.

      Version of Record online: 12 DEC 2003 | DOI: 10.1002/pola.10877

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      This presentation summarizes historical developments in fundamental research covering cellulose structure and biosynthesis. Major advances in structure include: discovery of a new sub allomorph of cellulose I; lattice imaging of glucan chains showing no fringe micelle structure; parallel chain orientation in cellulose I; and discovery of nematic ordered cellulose. Advances in biosynthesis include: discovery of the TC (terminal synthesizing complex); isolation and purification of cellulose synthase; in vitro synthesis of cellulose I; and synthetic cellulose assembly. The presentation will focus on recent molecular biology advances with cellulose concluding with thoughts about future uses in textile and forest products industries.

    11. Preparation of polyethylene block copolymers by a combination of postmetallocene catalysis of ethylene polymerization and atom transfer radical polymerization (pages 496–504)

      Yoshihisa Inoue and Krzysztof Matyjaszewski

      Version of Record online: 15 DEC 2003 | DOI: 10.1002/pola.10876

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      The synthesis of block copolymers consisting of a polyethylene segment and either a poly(meth)acrylate or polystyrene segment was accomplished through the combination of postmetallocene-mediated ethylene polymerization and subsequent atom transfer radical polymerization. A vinyl-terminated polyethylene was synthesized by the polymerization of ethylene with a phenoxyimine zirconium complex as a catalyst. This polyethylene was efficiently converted into an atom transfer radical polymerization macroinitiator by the addition of α-bromoisobutyric acid to the vinyl chain end, and the polyethylene macroinitiator was used for the atom transfer radical polymerization of n-butyl acrylate, methyl methacrylate, or styrene; this resulted in defined polyethylene-b-poly(n-butyl acrylate), polyethylene-b-poly(methyl methacrylate), and polyethylene-b-polystyrene block copolymers.

    12. Toward self-assembling dendritic macromolecules from conventional monomers by a combination of living radical polymerization and irreversible terminator multifunctional initiator (pages 505–513)

      Virgil Percec, Cristian Grigoras and Hyoung-J. Kim

      Version of Record online: 12 DEC 2003 | DOI: 10.1002/pola.11014

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      TERMINI stands for irreversible terminator multifunctional initiator and represents a new concept elaborated in our laboratory for the design of novel macromolecules with complex architecture from a diversity of commercial monomers. This article elaborates a method for the iterative divergent synthesis of dendritic poly(methyl methacrylate) containing a bifunctional core at its focal point by using a combination of self-regulated metal-catalyzed living radical polymerization and TERMINI.

    13. Synthesis and characterization of linear tetrablock quarterpolymers of styrene, isoprene, dimethylsiloxane, and 2-vinylpyridine (pages 514–519)

      Panagiota G. Fragouli, Hermis Iatrou and Nikos Hadjichristidis

      Version of Record online: 15 DEC 2003 | DOI: 10.1002/pola.10856

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      Well-defined tetrablock quarterpolymers of styrene, isoprene, dimethylsiloxane, and 2-vinypyridine were synthesized with anionic polymerization high-vacuum techniques and selective linking reactions (heterofunctional linking agents).

    14. Novel reaction between cyclic formal and ethylene oxide (pages 520–533)

      Naoaki Yamasaki and Junzo Masamoto

      Version of Record online: 17 DEC 2003 | DOI: 10.1002/pola.10861

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      Novel reactions between trioxane and ethylene oxide were discovered, and three novel cyclic formals were isolated and identified. This type of reaction was not limited to the reaction between trioxane and ethylene oxide but was also found to be generalized to the reaction between the cyclic formal and ethylene oxide.

    15. Synthesis of block copolymers by combined ultrasonic irradiation and reverse atom transfer radical polymerization processes (pages 534–540)

      Mustafa Degirmenci, Huceste Catalgil-Giz and Yusuf Yagci

      Version of Record online: 15 DEC 2003 | DOI: 10.1002/pola.10879

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      A two-step procedure based on ultrasonic irradiation and reverse atom transfer radical polymerization (RATRP) for the synthesis of block copolymers is described. In the first step of the procedure, a stable chlorine-end-capped polymer is formed upon the ultrasonic irradiation of poly(methyl methacrylate) (PMMA) in dry benzene in the presence of a copper chloride/2,2′-bipyridine catalyst. Heating the system to 110 °C initiates the polymerization of the second monomer, styrene, and this results in the formation of the block copolymers. The degradation behavior of PMMA under ultrasonic irradiation has also been studied. The agreement of the experimentally obtained molecular weights and theoretical molecular weights and the unimodal shapes of the gel permeation chromatography curves of the block copolymers indicate the controlled nature of the RATRP process initiated by polymeric radicals formed by sonication.

    16. Synthesis, structural analysis, and self-assembly of phenylene ethynylene oligomers and their [BOND]F, [BOND]CF3, and [BOND]CH3 substituted derivatives (pages 541–550)

      Simona Percec, Ross Getty, Will Marshall, Gabriel Skidd and Roger French

      Version of Record online: 16 DEC 2003 | DOI: 10.1002/pola.10949

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      Oligomers consisting of aromatic building blocks linked together via alkynyl units were synthesized by Sonogashira cross-coupling of aryl halides with terminal acetylenes. Strong electron acceptors such as [BOND]F and [BOND]CF3 and weak electron donors like [BOND]CH3 were placed as substituents on one of the benzene rings. Single crystals were analyzed by X-ray diffraction experiments that revealed structural details that could lead to a better understanding of the electron-transport properties. Patterned self-assembled monolayers self-assembled monolayers (SAMs) of some of these molecules and comparison alkane thiols were obtained on gold by microcontact printing or flooding. Surface potential differences between adjacent SAMs or between SAMs and the gold substrate were measured by scanning surface potential microscopy under ambient conditions.

    17. Theoretical and experimental X-ray photoelectron spectroscopy investigation of ion-implanted nafion (pages 551–556)

      Eufrozina A. Hoffmann, Zoltan A. Fekete, Ljiljana S. Korugic-Karasz, Frank E. Karasz and Eugene Wilusz

      Version of Record online: 15 DEC 2003 | DOI: 10.1002/pola.10878

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      The membrane properties of a Nafion surface can be modified by ion implantation with N+ or F+. The results are presented of an X-ray photoelectron spectroscopy (XPS) study of implanted surfaces. For the interpretation of the XPS spectra, calculations using a semiempirical quantum chemical formalism (Austin Model 1) have been applied, in conjunction with a charge-potential model, to predict the C1s core electron binding energies.

    18. Competition between the formation of excimers and excitons during the photoluminescence of light-emitting polymer blends (pages 557–565)

      J. S. Lee, C. H. Kim, J.-W. Yu, J. K. Kim, D. Y. Kim, N. W. Song and C. Y. Kim

      Version of Record online: 15 DEC 2003 | DOI: 10.1002/pola.10931

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      A schematic representation of the pathways of energy transfer and excimer formation is shown. Thin arrows represent excitation, solid arrows represent light emission, and broken lines represent energy transfer. S0 is the ground state; S1(d) and S1(a) are the lowest excited states of the donor and acceptor, respectively; Sv is the energy-transfer level; Scr is the critical energy level for the formation of excimers; Sex is the energy level of excimers; and hν is the light emission.

    19. Stimuli-responsive polymers. VII. Photomodulated chiroptical switches: Periodic copolyaramides containing azobenzene, phenylene, and chiral binaphthylene main-chain linkages (pages 566–577)

      Gary D. Jaycox

      Version of Record online: 15 DEC 2003 | DOI: 10.1002/pola.10806

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      Conformationally restricted copolyaramides containing a combination of 4,4′-azobenzene, 1,4-phenylene, and chiral 2,2′-binaphthylene main-chain segments exhibit photoresponsive chiroptical behavior stemming from multiple trans-cis-isomerization reactions triggered within their polymer backbones. In contrast to their more randomly constructed counterparts, copolymer variants endowed with periodic backbone structures undergo reversible, wavelength-dependent inversions in their optical rotations in response to multiple ultraviolet-light/visible-light illumination cycles. Similar behavior is also observed for a smaller oligomer fitted with a periodic arrangement of its monomer units. In their present forms, the periodic constructs constitute a new class of solution-based, photomodulated chiroptical switches that may be suitable for applications in a number of emerging technological areas.

    20. Poly(vinyl chloride) on the way from the 19th century to the 21st century (pages 578–586)

      D. Braun

      Version of Record online: 24 DEC 2003 | DOI: 10.1002/pola.10906

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      This article discusses the evolution of poly(vinyl chloride) (PVC) from the 19th to the 21st century.

    21. Aminotelechelics: A convenient synthesis and characterization of primary amino-terminated telechelic poly(propylene glycol) and polyisobutylene (pages 587–596)

      Sándor Kéki, Miklós Nagy, György Deák, Pál Herczegh and Miklós Zsuga

      Version of Record online: 15 DEC 2003 | DOI: 10.1002/pola.10905

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      The synthesis of amino-terminated telechelic poly(propylene glycol) and polyisobutylene from their corresponding dihydroxy-terminated derivatives was studied. The synthesis of these aminotelechelics was achieved by the coupling of imidazolylformates with ethylenediamine. The structures of the resulting amino-functionalized polymers were determined by 1H NMR, 13C NMR, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. On the basis of the spectroscopic and spectrometric results, a complete conversion of dihydroxy termini into diamino end groups was observed; that is, the number-average functionality was found to be 2.

    22. Preparation of macromonomers by copolymerization of methyl acrylate dimer involving β fragmentation (pages 597–607)

      Takahiro Harada, Per B. Zetterlund and Bunichiro Yamada

      Version of Record online: 16 DEC 2003 | DOI: 10.1002/pola.10803

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      The copolymerization of the unsaturated dimer of methyl acrylate (MAD) with various monomers was found to be a convenient way of preparing acrylate–MAD copolymers with unsaturated end groups at the ω end (macromonomers) introduced via β fragmentation of the MAD propagating radical. The efficiency of end-group introduction increased with temperature for copolymerizations with cyclohexyl and n-butyl acrylate. Copolymerization with ethyl methacrylate (EMA) resulted in only low contents of unsaturated end groups, probably because of the reversible addition of the poly(EMA) radical to MAD. Copolymerization with ethyl α-ethyl acrylate did yield a copolymer containing unsaturated end groups, although the steric hindrance of the ethyl group caused low polymerization rates.

    23. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis of atom transfer radical polymerization macroinitiators derived from poly(3-ethyl-3-hydroxymethyloxetane) (pages 608–614)

      Melania Bednarek and Przemysław Kubisa

      Version of Record online: 17 DEC 2003 | DOI: 10.1002/pola.10850

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      An analysis of matrix-assisted laser desorption/ionization time-of-flight signal splitting due to the presence of 79Br and 81Br isotopes allows the exact determination of the functionality of multifunctional atom transfer radical polymerization macroinitiators obtained by the functionalization of poly(3-ethyl-3-hydroxymethyloxetane) with 2-bromoisobutyryl bromide.

    24. Studies of the surface layer structure and properties of poly(styrene/α-t-butoxy-ω-polyglycidol) microspheres by carbon nuclear magnetic resonance, X-ray photoelectron spectroscopy, and the adsorption of human serum albumin and γ-globulins (pages 615–623)

      Teresa Basinska, Stanislaw Slomkowski, Slawomir Kazmierski, Andrzej Dworak and Mohamed M. Chehimi

      Version of Record online: 17 DEC 2003 | DOI: 10.1002/pola.10863

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      Poly(styrene/α-t-butoxy-ω-polyglycidol) microspheres (diameter = 220 nm) were synthesized by the radical copolymerization of styrene and α-t-butoxy-ω-vinylbenzyl-polyglycidol macromonomers (number-average molecular weight = 950 or 2700). The surfaces of these microspheres were enriched with polyglycidol. The mobility of polyglycidol in the particle surface layers was characterized by spin–lattice relaxation times in 13C NMR spectra of particle suspensions. Longer polyglycidol chains at the particle surfaces were more mobile and more greatly reduced the adsorption of proteins onto the microspheres.

    25. Biofunctional rapid prototyping for tissue-engineering applications: 3D bioplotting versus 3D printing (pages 624–638)

      Andreas Pfister, Rüdiger Landers, Andres Laib, Ute Hübner, Rainer Schmelzeisen and Rolf Mülhaupt

      Version of Record online: 17 DEC 2003 | DOI: 10.1002/pola.10807

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      Polyurethane scaffolds for tissue-engineering applications were prepared with rapid-prototyping technologies (3D Printing and 3D Bioplotting). The scaffold architectures were monitored with X-ray microtomography. The scaffold performance was associated with heterogeneous and homogeneous polyurethane crosslinking.

    26. Analysis of surface mobility in polystyrene films with monodisperse and bimodal molecular weights by lateral force microscopy (pages 639–647)

      Tisato Kajiyama, Keiji Tanaka and Atsushi Takahara

      Version of Record online: 18 DEC 2003 | DOI: 10.1002/pola.10873

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      The surface glass-transition temperature (Tmath image) in monodisperse polystyrene (PS) films was examined on the basis of the temperature dependence of the lateral force at a given scanning rate. Tmath image of the PS films was found to be markedly lower than the corresponding bulk glass-transition temperature over the entire molecular weight range (4900–1,460,000). Also, the apparent activation energy of the surface segmental motion in the PS films was 230 ± 10 kJ mol−1, significantly smaller than that for bulk PS. Finally, Tmath image measurement by lateral force microscopy was applied to binary PS mixtures with different molecular weights. On the basis of the Gordon–Taylor equation, the surface composition of the shorter component in the blend films was successfully obtained.

    27. Thermal oxidation of nonstabilized and stabilized polymers and chemiluminescence (pages 648–660)

      L. Matisová-Rychlá and J. Rychlý

      Version of Record online: 18 DEC 2003 | DOI: 10.1002/pola.10847

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      The chemiluminescence under isothermal and nonisothermal conditions accompanying the oxidation of some polymers (polyolefins, polyamides, and polysaccharides) has been examined from the viewpoint of its relationship with the rate of oxidation. The position and applicability of the chemiluminescence method, among other approaches, to the investigation of polymer thermal oxidation is shown to the right.

    28. Hydrogen-bonded supramolecular poly(ether ketone)s (pages 661–674)

      Michael J. Kunz, Getraud Hayn, Robert Saf and Wolfgang H. Binder

      Version of Record online: 18 DEC 2003 | DOI: 10.1002/pola.10858

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      The preparation of 2,4-diamino-1,3,5-triazine telechelic poly(ether ketone)s (triazine PEKs) and the formation of supramolecular polymers with dodecyl-(α-ω)-bis(5-methyl-1,3-pyrimidine-2,4-dione) were investigated. Both structures interacted by complementing hydrogen-bonding units present at their respective chain ends, this being reminiscent of triple hydrogen bonding in DNA. The preparation of the triazine PEKs started from hydroxyl-terminated poly(ether ketone)s by a nucleophilic displacement reaction with 2,4-diamino-6-(4-fluorophenyl)-1,3,5-triazine. With this method and molecular weight control via the Carothers equation, a series of triazine PEKs with a complete degree of end-group functionalization were prepared. The structure of the polymers was proven by 13C NMR spectroscopy and matrix-assisted laser desorption/ionization spectroscopy. When mixed as a 1:1 complex in solution with dodecyl-(α-ω)-bis(5-methyl-1,3-pyrimidine-2,4-dione), short triazine PEKs (molecular weight = 5700 or 10,000) showed a temperature-dependent association behavior visible via dynamic NMR spectroscopy. Additional proof of the formation of a supramolecular, hydrogen-bonded network was derived from solid-state NMR spectroscopy, differential scanning calorimetry, and rheological investigations.

    29. Role of minority structures and mechanism of peroxide crosslinking of polyethylene (pages 675–688)

      Milan Lazár, Angela Kleinová, Agnesa Fiedlerová, Ivica Janigová and Eberhard Borsig

      Version of Record online: 19 DEC 2003 | DOI: 10.1002/pola.10809

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      Minority structures are considered to be defect structures that are formed during polyethylene (PE) preparation and during the crosslinking process in PE. The minority structures that play the predominant role in PE crosslinking are vinyl double bonds. Moreover, the decomposition of dicumyl peroxide in PE does not proceed according to first-order kinetics, but induced peroxide decomposition also takes part.

    30. Modified poly(ϵ-caprolactone)s and their use for drug-encapsulating nanoparticles (pages 689–700)

      Cristina Iojoiu, Thierry Hamaide, Valeria Harabagiu and Bogdan C. Simionescu

      Version of Record online: 18 DEC 2003 | DOI: 10.1002/pola.10849

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      Well-defined poly(ϵ-caprolactone) (PCL)-polydimethylsiloxane diblock and triblock copolymers and poly(ϵ-caprolactone-co-4-ethylcaprolactone) random copolymers were prepared through the homogeneously catalyzed coordination anionic polymerization of ϵ-caprolactone (CL) and the copolymerization of CL with 4-ethyl-ϵ-caprolactone in the presence of hydroxy-terminated polysiloxanes or allyl alcohol as chain-transfer agents, respectively. As proven by differential scanning calorimetry analysis, the presence of siloxane blocks and ethylcaprolactone units determined the diminished copolymer crystallinity, which was shown by the reduced melting temperatures and enthalpy of fusion with respect to those of pure PCL. Both types of copolymers were found to form, in the presence of a poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) emulsifier, monodisperse and stable nanoparticles able to encapsulate different types of bioactive compounds (Vitamin E and indomethacin).

    31. Polycationic salts. VI. Synthesis and in vitro studies of 2-ionene oligomer derivatives of styrene as bile acid sequestering agents (pages 701–713)

      Peter Zarras

      Version of Record online: 19 DEC 2003 | DOI: 10.1002/pola.10948

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      Several vinylbenzyltri-n-alkyl ammonium salts were prepared via the Menshutkin reaction as well as salts based on 2-ionene oligomers. These salts were polymerized using either aqueous or organic solvents with azo-initiators to high molecular weight polymers. Several of these polymers exhibited higher bile acid sequestering activity relative to cholestyramine.

    32. Phototriggered atmospheric degradation of poly[methyl(phenyl)silanediyl] in the presence of ultraviolet absorbers (pages 714–721)

      O. Meszároš, P. Schmidt, J. Pospíšil and S. Nešpůrek

      Version of Record online: 19 DEC 2003 | DOI: 10.1002/pola.10904

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      Oxidative changes in poly[methyl(phenyl)silanediyl (PMPSi) films exposed in a Weather-O-Meter ATLAS Ci 3000+ were monitored by Fourier transform infrared spectroscopy. Increases in absorption in the regions of oxygenated products, decreases in absorption in the polysilane backbone region, and changes in the aromatic C[BOND]H bond region were observed. Experiments in a gas cell in argon or air indicated the key role of oxygen in the process. The photooxidation of PMPSi was retarded by triazine- and oxalanilide-based ultraviolet absorbers [2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-(hexyloxy)phenol and N-(4-tert-butyl-2-ethoxyphenyl)-N′-(2-ethylphenyl)oxalanilide] protecting the polymer by the excited-state intramolecular proton-transfer mechanism.

    33. Design and synthesis of Ru(II-bipyridyl-containing conjugated polymers (pages 722–732)

      Thomas Pautzsch, Lars Blankenburg and Elisabeth Klemm

      Version of Record online: 19 DEC 2003 | DOI: 10.1002/pola.10874

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      A series of novel π-conjugated polymers containing ruthenium bipyridine complexes was synthesized by a cross-coupling reaction and characterized. These polymers exhibit absorption maxima around 330–350 nm (π-π*) and 460–500 nm metal-to-ligand charge transfer (MLCT), respectively. They are soluble in common organic solvents, and all polymers can be converted into transparent films. We investigated the influence of different donating and acceptor diethynylarenes of the ultra-violet-visible spectra. The oxidation potential, which was measured by cyclic- and square-wave voltametry, showed a typical Ru2+/3+ exhibited at 1.25 V versus the saturated calomel electrode. The polymers were further characterized with photoluminescence measurements. When excited at 442 nm (11a), the polymer exhibited an emission peak at 690 nm. This peak was attributed to the MLCT states.

    34. Structure and properties of poly(methyl methacrylate) particles prepared by a modified microemulsion polymerization (pages 733–741)

      Wan Jiang, Wuli Yang, Xianbiao Zeng and Shoukuan Fu

      Version of Record online: 19 DEC 2003 | DOI: 10.1002/pola.10864

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      Nanoscale poly(methyl methacrylate) (PMMA) particles were prepared by modified microemulsion polymerization. Different from those made by traditional microemulsion polymerization, the particles prepared by the modified procedure were multichain systems. PMMA samples prepared by these two procedures had glass-transition temperatures greater than 120 °C and were rich in syndiotactic content (55–61% rr).

    35. Influence of a cationic polyelectrolyte on the inverse micellar region of the ternary system sulfobetaine/water/alcohol (pages 742–751)

      J. Koetz, J. Bahnemann and S. Kosmella

      Version of Record online: 19 DEC 2003 | DOI: 10.1002/pola.10808

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      By the addition of a cationic polyelectrolyte to the sulfobetaine (SB)/water/heptanol system, the inverse microemulsion phase can be shifted in direction to the water corner, and polyelectrolyte-stuffed microemulsion droplets of about 40 nm can be detected by freeze-fracture electron microscopy.

    36. New photocleavable structures. II. α-Cleavable photoinitiators based on pyridines (pages 752–764)

      R. Liska and D. Herzog

      Version of Record online: 19 DEC 2003 | DOI: 10.1002/pola.10859

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      A series of novel pyridine-based type I photoinitiators were synthesized. UV spectroscopy revealed absorption characteristics very similar to those of a commercially available hydroxyalkylphenone [2-hydroxy-2-methyl-1-phenyl propan-1-one (1b)]. Photo-differential scanning calorimetry under a nitrogen atmosphere of a 3-substituted derivative [2-hydroxy-2-methyl-1-pyridin-3-yl-propan-1-one (3b)] gave results comparable to those obtained with 1b. Measurements under air indicated decreased sensitivity toward oxygen quenching reactions. Additionally, pyridine derivatives showed good water solubility (4.9 g/100 mL). With preliminary steady-state photolysis experiments, the α-cleavage mechanism was found to be the main reaction pathway. The quantum yields of α-cleavage were approximately 0.30 ± 0.04 for 3b and 0.18 ± 0.03 for 1b.

    37. Network formation of a phenyl vinyl ketone copolymer with 4-vinylbenzil and its photodecrosslinking in films (pages 765–771)

      Jaroslav Mosnáček, Ivan Lukáč, Štefan Chromik, Ivan Kostič and Pavol Hrdlovič

      Version of Record online: 19 DEC 2003 | DOI: 10.1002/pola.10860

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      The irradiation (λ > 400 nm) in air of a copolymer of phenyl vinyl ketone with 4-vinylbenzil (VBZ) containing 1.5 wt % VBZ structural units in film, followed by the thermal decomposition of the resulting pendant benzoyl peroxide groups, leads to crosslinking. The additional irradiation of the crosslinked polymer at 366 nm results in the cleavage of the poly(phenyl vinyl ketone) chain between the junction points of the polymer network through a Norrish type II reaction. Therefore, a novel type of photoresist based on polymer network decrosslinking can be prepared.

    38. Thermosensitive sol–gel transition behaviors of poly(ethylene oxide)/aliphatic polyester/poly(ethylene oxide) aqueous solutions (pages 772–784)

      M. J. Song, D. S. Lee, J. H. Ahn, D. J. Kim and S. C. Kim

      Version of Record online: 19 DEC 2003 | DOI: 10.1002/pola.10851

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      Triblock copolymers of PEO and aliphatic polyesters were prepared by hexamethylene diisocyanate coupling and dicyclohexyl carbodiimide coupling. Through changes in the molecular weight and hydrophobicity of the polyester middle block, the hydrophobic–hydrophilic balance of each block was systematically controlled. With the hydrophobicity and molecular weight of the middle block increasing, the critical micelle concentration at the critical micelle temperature decreased, and the absolute value of the micellization free energy increased. The micelle size was rather insensitive to temperature but slightly decreased with increasing temperature.

    39. Synthesis and characterization of stereoregular poly(methyl methacrylate)–silica hybrid utilizing stereocomplex formation (pages 785–794)

      Achimuthu Ashok Kumar, Kaoru Adachi and Yoshiki Chujo

      Version of Record online: 19 DEC 2003 | DOI: 10.1002/pola.10880

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      Stereoregular poly(methyl methacrylate) (PMMA)-silica nanocomposites were prepared using stereocomplex formation between isotactic PMMA and syndiotactic PMMA by an in situ method. The methodology adopted here is, the simultaneous formation of organic gel and inorganic gel, the so-called interpenetrating network formation (IPN). The gelation of isotactic and syndiotactic PMMA was performed by stereocomplex formation with the associated segments forming the crosslink points in the presence of tetramethoxysilane (TMOS).

    40. My life with polymer science (pages 795–818)

      Otto Vogl

      Version of Record online: 24 DEC 2003 | DOI: 10.1002/pola.10932

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      This summary covers nearly 55 years of my involvement in various areas of polymer science. Much of the work was done in polymer synthesis. The contributions were in the following fields: 1. Polymerization of higher aliphatic aldehydes, isotactic polyaldehydes and side chain crystallization; 2. Polymerization of chloral (and other trihaloacetaldehydes), macromolecular asymmetry and the single helix; 3. Functional polymers including polymeric stabilizers (with emphasis on UV stabilizers), polymeric drugs, spacers in polymers; 4. Polymers with unusual structures such as head-to-head polymers; regular copolyamides for desalination membranes and (novel methods to prepare) high-temperature polymers, polycations for bile acid sequestering to reduce blood cholesterol levels; 5. Novel polymerization techniques, including polymerization under extreme pressures, cryotachensic polymerization; 6. Oriental lacquers as a contribution to polymer science and the arts, chiral crystallization; and 7. As the last contribution we described the ultimate uniformity in polymer structures, the isotope distribution of uniform polymers.

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