Journal of Network Polymer,Japan
Online ISSN : 2186-537X
Print ISSN : 1342-0577
ISSN-L : 1342-0577
Special issues: Journal of Network Polymer,Japan
Volume 38, Issue 1
Networked Polymer Synthesis - Foundation and Application
Displaying 1-8 of 8 articles from this issue
Review
  • Takehiro Fujita, Shigeru yamago
    2017 Volume 38 Issue 1 Pages 4-13
    Published: January 10, 2017
    Released on J-STAGE: June 14, 2017
    JOURNAL FREE ACCESS

    Living radical polymerization (LRP) is a polymerization method to control molecular weight, distribution, and monomer sequence under radical conditions. Significant developments have been made to explore new LRP methods and their applications to fabricate polymer materials since the report by Georges in 1993. In this review, recent two topics related to the activation of dormant species in LRP are described. At first, use of photochemistry in the activation of dormant species is described. The new condition has several advantages including the increase of macromolecular structure and the lowering catalyst loading. Secondly, LRP of unconjugated monomers is discussed. While LRP of unconjugated monomers is more difficult than that of conjugated monomers, appropriate choice of LRP method and conditions allow the controlled homo and copolymerization of unconjugated monomers. These results clearly expand the synthetic ability of LRP for fabricating functional polymer materials.

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  • Toshihiro Tadaki
    2017 Volume 38 Issue 1 Pages 14-20
    Published: January 10, 2017
    Released on J-STAGE: June 14, 2017
    JOURNAL FREE ACCESS

    The anionic polymerization is available for synthesizing tailor-made polymers. Fuel efficient tire and semiconductor patterning as the recent advanced applications in industry are summarized in this article.

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  • Sadahito Aoshima, Arihito Kanazawa, Shokyoku Kanaoka
    2017 Volume 38 Issue 1 Pages 21-28
    Published: January 10, 2017
    Released on J-STAGE: June 14, 2017
    JOURNAL FREE ACCESS

    Cationic polymerization has a long history and various types of monomers have been examined. However, the inherently unstable propagating species causing a variety of side reactions had made it difficult to achieve controlled and/or living reactions in cationic polymerization, retarding the discovery of living cationic polymerization. The first part of this review focuses such historical and basic information about cationic polymerization and living cationic polymerization reactions including the HI/I2 system and the strong Lewis acid systems by using additives, weak Lewis bases and salts. In the second part, recent extensive researches on living cationic polymerization are demonstrated. For example, Lewis acid catalysts with a weak base led to unprecedented living reaction systems, such as a wide range of available choices of metal halide catalysts, fast living polymerization within 1-2 sec, heterogeneous living polymerization with Fe2O3. The last part summarizes new classes of monomers and reactions: new naturally occurring monomers available, novel controlled polymerization systems including the RAFT cationic polymerization, the alternating copolymerization of aldehydes and vinyl ethers, the monomer-selective copolymerization, and the concurrent cationic vinyl-addition and ring-opening copolymerization of vinyl ethers and oxiranes. Especially, the quantitative synthesis of star-shaped polymers with a narrow MWD by the base-assisting living cationic polymerization was described in detail.

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  • Takeshi Endo, Atsushi Sudo
    2017 Volume 38 Issue 1 Pages 29-38
    Published: January 10, 2017
    Released on J-STAGE: June 14, 2017
    JOURNAL FREE ACCESS

    Ring-opening polymerization is one of the most important strategies for synthesis of networked polymers. Its characteristics, (1) applicability to synthesis of polymers with main chains containing heteroatoms and functional groups, (2) tunability of polymerization behaviors by structural parameters of cyclic monomers such as ring size and elements which cyclic monomers are consisted of, (3) possibility to control their polymerizations by living polymerization techniques, (4) equilibrium nature, and (5) small volume shrinkages upon polymerizations, have allowed for the development of networked polymers with various functions and high performances. This review describes some typical examples of molecular designs of networked polymers based on the characteristics of ring-opening polymerization and their future prospects.

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  • Yoshimasa Matsumura, Bungo Ochiai
    2017 Volume 38 Issue 1 Pages 39-45
    Published: January 10, 2017
    Released on J-STAGE: June 14, 2017
    JOURNAL FREE ACCESS

    Ring-closing polymerization (cyclopolymerization) is a very useful synthetic method for preparation of polymers possessing cyclic structures. These polymers containing cyclic structures are applied for high strength materials, and so on due to their good rigidity and high density. In addition, these polymers are applicable as molecular sensors, scavengers, stationary phases for chromatography, and so on by their specific interactions with ions and molecules. Ring-closing polymerization through 5- or 6-membered ring formation proceeds smoothly owing to the thermodynamic stability of the ring structures. In contrast, that with large ring formation requires precise molecular design of corresponding monomers. The resulting large ring structures potentially exhibit excellent and unique molecular recognition abilities. Herein, we review recent studies on ring-closing polymerization through large ring formation and applications of polymers bearing large the cyclic structures obtained by these polymerizations.

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  • Daisuke Takeuchi, Kotaro Osakada
    2017 Volume 38 Issue 1 Pages 46-50
    Published: January 10, 2017
    Released on J-STAGE: June 14, 2017
    JOURNAL FREE ACCESS

    Basic topics and recent progress on olefin polymerization by transition metal catalysts are described. Various metal complexes have been utilized as catalysts for olefin polymerization, which enable control of stereoregularity and copolymer composition of polyolefins. Formation of polyolefins having network structure and their application as elastomers are also described.

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  • Hiroaki Imoto, Susumu Tanaka, Kensuke Naka
    2017 Volume 38 Issue 1 Pages 51-58
    Published: January 10, 2017
    Released on J-STAGE: June 14, 2017
    JOURNAL FREE ACCESS

    polymers having a unique structure, which is difficult to construct by conventional structures. During the past decade, these synthetic obstacles have been overcome through many creative procedures. Organic conjugated polymers are of much current academic and technological interest due to their optical and electronic properties. Various types of main group element-containing conjugated polymers have been synthesized using silicon, nitrogen, and sulfur. This review focuses on recent development of the main group element-containing conjugated polymers, such as conjugated organo-boron, silicon, germanium, -tin, -phosphorus, and -arsenic polymers. Synopsis Polymers containing inorganic elements in the main chain structure are of current interest as a result of their unique properties. The development of a new polymerization reaction makes it possible to create organic-inorganic hybrid.

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  • Mutsuhisa Furukawa
    2017 Volume 38 Issue 1 Pages 59-66
    Published: January 10, 2017
    Released on J-STAGE: June 14, 2017
    JOURNAL FREE ACCESS

    Polyurethanes are typical polymers synthesized by polyaddition reaction. This article reviews reactions used in polyurethane synthesis, reaction mechanism of isocyanate with active hydrogen groups by use of quantum computer chemistry, the role of hard segment length, and design criteria of high performance polyurethanes. The reactions were speculated to proceed via formation of hydrogen bonding and six membered ring 1: 2 complexed of isocyanate with alcohol, water, and amine. The calculated activation energy for reaction of phenyl isocyanate with ethanol or methylamine was 12.4 and 4.12 kcal mol-1, respectively. The design criteria of polyurethane are described from a point of view of chemical and physical factors.

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