Polyrtaxane Networks as a topologically cross-linked polymer: Synthesis and properties in Supramolecular Polymer Chemistry Willey-VCH 2012 Author:Yasuhito Koyama, Takayuki Arai, Yasuhiro Kohsaka, Masahiro Shioya, Toshikazu Takata
論文 High-Speed Synthesis of Thermo-responsive Polymers by Boosted Polymerization of N,N-Diethyl Acrylamide in High-Temperature Water Industrial & Engineering Chemistry Research,61(46):17012-17016 2022(Nov. 09) Author:Sumito Ishii, Akinori Sezai, Yasuhiro Kohsaka, Shigeru Deguchi, and Mitsumasa Osada
Diverse chemically recyclable polymers obtained by cationic vinyl and ring-opening polymerizations of the cyclic ketene acetal ester “dehydroaspirin” Polymer Chemistry 2022(Oct. 17) Author:Akane Kazama, Yasuhiro Kohsaka
(REVIEW) Polymer Chemistry of alpha-Substituted Acrylates Designed for Functional-Group Synergy Journal of Macromolecular Science, Part A 2021(Oct. 13) Author:Y. Kohsaka, Y. Akae, R. Kawatani, A. Kazama Abstract:This article overviews the polymer chemistry of acrylates designed for functional-group synergy among the vinyl group and ester- and alpha-substituents. alpha-Substituents have been incorporated to tune the reactivity of the vinyl group; for example, ethyl alpha-cyanoacrylate, known as instant adhesions, has high reactivity to initiate anionic polymerization using moisture. Moreover, alpha-acyloxyacrylates undergo radical polymerization, increasing the degree of polymerization in proportion to monomer conversions due to the stabilized radical species by the captodative effect. alpha-Arylacrylates produced alternating copolymers with methyl methacrylate (MMA) using anionic polymerization, which exhibited specific fluorescence. alpha-(Aminomethyl)acrylates stabilized by intramolecular hydrogen bonding yielded a pH-/thermo-responsive polymer. Anionic polymerization of alpha-(alkoxymethyl)acrylates resulted in high isotacticity due to the chelating effect at the propagating chain end. alpha-(Halomethyl)acrylates underwent a nucleophilic conjugate substation reaction, applied to end-functionalization, polycondensation, and polymer degradation. For a long time, ring-opening polymerization of cyclic acrylates has been considered difficult; however, it was recently achieved using sophisticated monomer design.
Synthesis of polyarylates and aliphatic polyesters by divalent acyl-1,2,4-triazole: a route to metal-free synthesis at low temperature Polymer Jouranl,53(8):887-893 2021(Apr. 20) Author:Y. Kohsaka, I. Mori, K. Homma, Y. Akae, D. Matsuura, Y. Kimura Abstract:Aromatic, semiaromatic, and aliphatic polyesters were synthesized at moderate temperatures (25–80 °C) by the polymerization of divalent acyl-1,2,4-triazoles using 4-(dimethylamino)pyridine as a catalyst. The monomers were prepared from divalent acyl chloride in high yields, although some of them required that toluene and pyridine be used as solvents due to their high crystallinity. Melt polymerization in diphenyl ether was effective in affording semiaromatic and aliphatic polyesters. However, this method was not suitable for aromatic polyesters, as the reaction system became heterogeneous at 80 °C. Nevertheless, solution and interfacial polymerization reactions were effective in obtaining aromatic polyesters. The novel monomers provided polyester synthesis at moderate temperature without the use of any metal catalyst or halide monomers.
（総説）官能基シナジーを引き出すビニルモノマーの設計と重合，機能 塗装工学,56(7):248-256 2021( 30) Author:髙坂泰弘 Abstract:This report reviews a strategy to design vinyl monomers using functional group synergy, which defined as intramolecular interaction between two or more functional group near polymerization points. One of the attractive motifs is alpha-functionalized acrylates, as the functionalized alpha-substituent can interact with vinyl and carbonyl groups by conjugation, hyperconjugation and intramolecular hydrogen bond. For example, alpha-arylacrylates undergoes alternating anionic copolymerization with methyl methacrylate; the alternating copolymers exhibited strong monomer emission, whereas the homopolymer, poly(alpha-arylacrylate)s exhibited excimer emission. alpha-(Halomethyl)acrylate undergoes nucleophilic conjugate substitution reaction in quantitative yield at room temperature even under air. This reaction was applied to monomer synthesis, end-functionalization, polycondensation and main chain scission reaction. This review also covers the design of recyclable vinyl polymer; a cyclic ketenacetal ester, dehydroaspirin, afforded the corresponding vinyl polymer by radical polymerization. The acid hydrolysis of the obtained vinyl polymer resulted in main chain scission with releasing the raw product of monomer, salicylic acid and acetic acid.
Controls and Effects of Monomer Junctions and Sequences in Curable and Degradable Polyarylate Containing Acrylate Moieties Macromol. Rapid Commun. 2021 Author:Y. Kohsaka, N. Nagai
Magnesium bromide (MgBr2) as a catalyst for living cationic polymerization and ring-expansion cationic polymerization" Polym. Chem 2021 Author:Y. Daito, R. Kojima, N. Kusuyama, Y. Kohsaka, M. Ouchi
Synthesis of Poly(Conjugated Ester)s by Ring-Opening Polymerization of Cyclic Hemiacetal Ester Bearing Acryl Skeleton European Polymer Journal,120:109185 2020 Author:Yasuhiro Kohsaka, Mai Yamashita, Yosuke Matsuhashi, Shuji Yamashita
End-reactive poly(tetrahydrofuran) for functionalization and graft copolymer synthesis via a conjugate substitution reaction Polymer Journal,52:75 2020 Author:Yasuhiro Kohsaka, Naoki Nagatsuka
Divergence of polycondensation by a tandem reaction based on sequential conjugate substitutions Polymer Chemistry,:5128 2020 Author:Keito Hagiwara, Yasuhiro Kohsaka
(FOCUS REVIEW) Conjugate substitution reaction of α-(substituted methyl)acrylates in polymer chemistry Polymer Journal,52:1175 2020 Author:Yasuhiro Kohsaka
Degradable and curable poly(conjugated ester)s prepared by acryl- and conjugate-substitutions of the ‘smallest’ monomer Eur. Polym. J.,141:110049 2020 Author:Y. Kohsaka, K. Nagai,
Radical Polymerization of ‘Dehydroaspirin’ with a Formation of Hemiacetal Ester Skeleton: A Hint for Recyclable Vinyl Polymers Polymer Chemistry,10:2764 2019 Author:Akane Kazama, Yasuhiro Kohsaka
Synthesis and properties of polyethers containing 1,3-butadiene skeleton in the backbones Chemistry Letters,48(8):894 2019 Author:Yasuhiro Kohsaka, Akira HIramatsu
Esterification with Aromatic Acyl-1,2,4-triazole Catalyzed by Weak Base at the Rate Comparable to Acyl Chloride CHEMISTRY LETTERS,47(1):100-102 2018 Author:Kohsaka, Yasuhiro; Homma, Kazumasa; Sugiyama, Susumu; Kimura, Yoshikazu;
Bifunctional Acyl-1,2,4-triazole: An Alternative Monomer of Dicarbonyl Chloride for Metal- and Halogen-free Polyester Synthesis CHEMISTRY LETTERS,47(2):221-224 2018 Author:Kohsaka, Yasuhiro; Homma, Kazumasa; Mori, Ichiro; Sugiyama, Susumu; Kimura, Yoshikazu;
(INVITED) Conjugate substitution and addition of alpha-substituted acrylate: a highly efficient, facile, convenient, and versatile approach to fabricate degradable polymers by dynamic covalent chemistry POLYMER CHEMISTRY,9(13):1610-1617 2018 Author:Kohsaka, Yasuhiro; Miyazaki, Takumi; Hagiwara, Keito;
Synthesis of isotactic poly[alpha-(hydroxymethyl)acrylate] by anionic polymerization of the protected monomer POLYMER BULLETIN,74(5):1935-1948 2017(May) Author:Kohsaka, Yasuhiro; Yamamoto, Kazuki; Suzawa, Kazuha; Kitayama, Tatsuki;
Synthesis and reaction of block copolymer composed of independently clickable segments via monomer-selective living copolymerization MICROSYSTEM TECHNOLOGIES-MICRO-AND NANOSYSTEMS-INFORMATION STORAGE AND PROCESSING SYSTEMS,23(5):1133-1140 2017(May) Author:Ladelta, Viko; Kohsaka, Yasuhiro; Kitayama, Tatsuki;
Polymerization of α-(Halomethyl)acrylates through Sequential Nucleophilic Attack of Dithiols using a Combination of Addition–Elimination and Click Reactions Polym. Chem.,8:976-979 2017 Author:Yasuhiro Kohsaka, Keito Hagiwara, Keiichiro Ito
Polymerization of alpha-(halomethyl)acrylates through sequential nucleophilic attack of dithiols using a combination of addition-elimination and click reactions POLYMER CHEMISTRY,8(6):976-979 2017 Author:Kohsaka, Yasuhiro; Hagiwara, Keito; Ito, Keiichiro;
Anionic polymerization of ethyl acrylate initiated by tetrabutylammonium azide: direct synthesis of end-clickable polyacrylate POLYMER CHEMISTRY,8(26):3858-3861 2017 Author:Kataoka, Yuki; Kohsaka, Yasuhiro; Kitaura, Takehiro; Domae, Shogo; Ishihara, Shoya; Kitayama, Tatsuki;
Acid- or photo-cleavable polyrotaxane: Subdivision of supramolecular main-chain type polyrotaxane structure induced by acidolysis or photolysis POLYMER,125:134-137 2017 Author:Araki, Jun; Honda, Yuta; Kohsaka, Yasuhiro;
α-Exomethylene lactone possessing acetal–ester linkage: Polymerization and postpolymerization modification for water-soluble polymer Journal of Polymer Science Part A: Polymer Chemistry,54(7):955-961 2016 Author:Kohsaka, Y; Matsumoto, Y; Zhang, T; Matsuhashi, Y; Kitayama, T Abstract:Spotlight Articleとして特別枠で収録
Synthesis of thermo-responsive polymer via radical (co)polymerization of N,N-dimethyl-α-(hydroxymethyl)acrylamide with N,N-diethylacrylamide Polymers,8:374 2016 Author:Yasuhiro Kohsaka, Yoshiaki Tanimoto
Synthesis and post-polymerization reaction of end-clickable stereoregular polymethacrylates via termination of stereospecific living anionic polymerization POLYMER CHEMISTRY,6(7):1078-1087 2015 Author:Kohsaka, Yasuhiro; Kurata, Takashi; Yamamoto, Kazuki; Ishihara, Shoya; Kitayama, Tatsuki;
Stereospecific Anionic Polymerization of α-(Hydroxymethyl)acrylate with Protective Group Macromol. Symp.,350:86-98 2015 Author:Yasuhiro Kohsaka, Kazuha Suzawa, Tatsuki Kitayama
C60-Containing polymethacrylates: synthesis, properties, and potential application as n-type semiconductor for organic solar cell Polym. Bull.,72:1265-1280 2015 Author:Viko Ladelta, Yasuhiro Kohsaka, Toshihiro Ohnishi, Michio Matsumura, Tatsuki Kitayama
Stereoregular poly(methyl methacrylate) with double-clickable omega-end: synthesis and click reaction POLYMER CHEMISTRY,6(19):3601-3607 2015 Author:Kohsaka, Yasuhiro; Yamamoto, Kazuki; Kitayama, Tatsuki;
Termination of living anionic polymerization of butyl acrylate with α-(chloromethyl)acrylate for end-functionalization and application to the evaluation of monomer reactivity Macromol. Chem. Phys.,216(14):1534-1539 2015 Author:Yasuhiro Kohsaka, Shoya Ishihara, Tatsuki Kitayama
α-(Aminomethyl)acrylate: Polymerization and spontaneous post-polymerization modification of β-amino acid ester for pH- / temperature-responsive material Polym. Chem.,6:5026-5029 2015 Author:Yasuhiro Kohsaka, Yusuke Matsumoto, Tatsuki Kitayama
（総説）メタクリル酸メチルの精密アニオン重合 : 分子量,立体規則性,末端構造の三元同時制御 日本ゴム協会誌 = Journal of the Society of Rubber Science and Technology, Japan,88(3):80-85 2015 Author:髙坂 泰弘; 北山 辰樹; Abstract:執筆依頼 Keywords:Living Anionic Ploymerization; Stereoregularity; End-functionalization; Stereospecific Polymerization; Tacticity; Click Chemistry;
Stimuli-degradable cross-linked polymers synthesized by radical polymerization using a size-complementary [3]rotaxane cross-linker POLYMER JOURNAL,46(1):67-72 2014 Author:Iijima, Keisuke; Kohsaka, Yasuhiro; Koyama, Yasuhito; Nakazono, Kazuko; Uchida, Satoshi; Asai, Shigeo; Takata, Toshikazu;
Anionic Alternating Copolymerization of alpha-Arylacrylates with Methyl Methacrylate: Effect of Monomer Sequence on Fluorescence JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY,52(19):2806-2814 2014 Author:Kohsaka, Yasuhiro; Yamaguchi, Eiji; Kitayama, Tatsuki;
Photodegradable cross-linked polymer derived from a vinylic rotaxane cross-linker possessing aromatic disulfide axle PURE AND APPLIED CHEMISTRY,85(4):835-842 2013 Author:Koyama, Yasuhito; Yoshii, Takahiro; Kohsaka, Yasuhiro; Takata, Toshikazu;
End-functional stereoregular poly(methyl methacrylate) with clickable C=C bonds: facile synthesis and thiol-ene reaction POLYMER CHEMISTRY,4(19):5043-5047 2013 Author:Kohsaka, Yasuhiro; Kurata, Takashi; Kitayama, Tatsuki;
An efficient synthetic entry to rotaxanes utilising reversible cleavage of aromatic disulphide bonds SUPRAMOLECULAR CHEMISTRY,23(1-2):65-68 2011 Author:Yoshii, Takahiro; Kohsaka, Yasuhiro; Moriyama, Taichi; Suzuki, Takao; Koyama, Yasuhito; Takata, Toshikazu;
Size-Complementary Rotaxane Cross-Linking for the Stabilization and Degradation of a Supramolecular Network ANGEWANDTE CHEMIE-INTERNATIONAL EDITION,50(21):4872-4875 2011 Author:Kohsaka, Yasuhiro; Nakazono, Kazuko; Koyama, Yasuhito; Asai, Shigeo; Takata, Toshikazu;
Graft Polyrotaxanes: A New Class of Graft Copolymers with Mobile Graft Chains ANGEWANDTE CHEMIE-INTERNATIONAL EDITION,50(44):10417-10420 2011 Author:Kohsaka, Yasuhiro; Koyama, Yasuhito; Takata, Toshikazu;
Main chain-type polyrotaxane with controlled ratio of rotaxanated units CHEMISTRY LETTERS,36(2):292-293 2007 Author:Takata, Toshikazu; Kohsaka, Yasuhiro; Konishi, Gen-ichi;
Polymer Synthesis, Degradation, Functionalization and Transformation by Conjugate Substitution Reaction S-Membrane International Conference 2019 (SMIC2019) 2019(Sep. 06) Presenter:Yasuhiro Kohsaka
Chemoselective Degradable Polymer by Monomer Designing International Symposium on Polymer Synthesis and Materials (PolySM) 2019(Sep. 04) Presenter:Yasuhiro Kohsaka
Conjugate substitution: Robust Chemistry for Polymer Synthesis, Degradation and Main Chain Exchanges The Polymer Society of Korea, 2019 Annual Spring Meeting”, Korea-Japan Joint Symposium: Fundamental Polymer Science for Future Technology 2019(Apr. 12) Presenter:Yasuhiro Kohsaka
Designed Monomers for Polymers Leading Backbone Destruction and Reconstruction Reactions The 99th Annual Meeting of The Chemical Society of Japan, Asian International Symposium - Polymer - 2019(Mar. 19) Presenter:Yasuhiro Kohsaka
Synthesis and Degradation of Polymers Prepared from Vinyl Monomers Bearing Cyclic Hemiacetal Ester Moieties The 10th International Conference of Modification, Degradation, and Stabilization of Polymers (MoDeSt2018) 2018 Presenter:Yasuhiro Kohsaka
Synthesis of Poly(conjugated ester)s by Polycondensation and Ring-Opening Polymerization for Chemically Degradable Biocompatible Polymers IUPAC Macro2018 2018 Presenter:Yasuhiro Kohsaka
Atropos Polymerization: Controlled Polymerization by Programmed Termination and Application Thereof 12th IUPAC International Conference on Ionic Polymerization (IP2017) 2017 Presenter:Yasuhiro Kohsaka
Polymer Synthesis by Tandem Reaction of α-(Halomethyl)acrylate via Addition-Fragmentation and Click Reactions The 12th International Conference on Advanced Polymers via Macromolecular Engineering (APME 2017) 2017 Presenter:Yasuhiro Kohsaka, Keito Hagiwara, Takumi Miyazaki,
Polymer Synthesis by Conjugate Substitution of α-(Halomethyl)acrylate 日本ゴム協会 第28回エラストマー討論会（英語招待講演） 2017 Presenter:Yasuhiro Kohsaka
Preparation of a ‘One-by-one Chain-Tethered’ type sliding graft copolymer 9th International Conference on Fiber and Polymer Biotechnology (IFPB2016) 2016 Presenter:Chihiro Otsubo, Yasuhiro Kohsaka, Jun Araki
Anionic Polymerization of Acrylates by Onium Salts with Aluminum Lewis Acid Activator World Congress on Living Polymerizations and Polymers (LPP16) 2016 Presenter:Kentaro Shirota, Yusuke Kataoka, Shogo Domae, Takehiro Kitaura, Yasuhiro Kohsaka, Tatsuki Kitayama
Anionic cyclopolymerization of α-linked diacrylate World Congress on Living Polymerizations and Polymers (LPP16) 2016 Presenter:Seungmin Choi, Nobuya Tanaka, Ren Sakamoto, Yasuhiro Kohsaka, Tatsuki Kitayama
Atropos Polymerization: Controlled Polymerization by Programmed Termination World Congress on Living Polymerizations and Polymers (LPP16) 2016 Presenter:Yasuhiro Kohsaka, Tatsuki Kitayama
Polymerization of Protected 2-(Hydroxymethyl)acrylate and Insolubilization/Water-Solubilization by Acid-hydrolysis Asian Conference on Adhesion 2016 (ACA2016) 2016 Presenter:Yasuhiro Kohsaka, Yusuke Matsumoto, Kazuki Yamamoto, Kazuha Suzawa, Tianyi Zhang, Yosuke Matsuhashi, Tatsuki Kitayama
One pot Ｓynthesis of Stereoregular Graft Copolymer of Polymethacrylate One-pot synthesis of Stereoregular Graft Copolymer of Polymethacrylate via Selective Termination with Monomer-bearing Terminator via Selective Termination with Monomer-bearing Term The 11th International Conference on Advanced Polymers via Macromolecular Engineering (APME 2014) 2015 Presenter:Shu Kano, Yasuhiro Kohsaka, Tatsuki Kitayama
Ring Opening Polymerization of β–butyrolactone by Onium Salts and Bulky Aluminum Phenoxide via O-Alkyl Scission Mechanism The 11th International Conference on Advanced Polymers via Macromolecular Engineering (APME 2015) 2015 Presenter:Taka-aki Tanaka, Takehiro Kitaura, Yasuhiro Kohsaka, Tatsuki Kitayama
Precise synthesis of poly(methyl methacrylate): Controls of molecular weight, stereoregularity, and end-Functionality International Conference on Smart Systems Engineering 2015 (SmaSys 2015) 2015 Presenter:Yasuhiro Kohsaka
Ethyl α-(aminomethyl)acrylate: An β-amino acid ester for pH/temperature-responsive polymers The 11th International Conference on Advanced Polymers via Macromolecular Engineering (APME 2015) 2015 Presenter:Yasuhiro Kohsaka, Yusuke Matsumoto, Tatsuki Kitayama
Ethyl α-(aminomethyl)acrylate : An amphiphilic monomer for pH- Temperature-responsive Polymers International symposium on Amphiphilic polymers, networks gels, and membranes (APNGM15) 2015 Presenter:Yasuhiro Kohsaka, Yusuke Matsumoto, Tatsuki Kitayama
End-clickable stereoregular poly(methyl methacrylate)s by termination of stereospecific anionic polymerization nternational Science and Nature Congress (ISNaC) 2015 2015 Presenter:Yasuhiro Kohsaka
Atropos polymerization: Spontaneous controls of molecular weight and end-functionality via programmed termination International Symposium on Ionic Polymerization 2015 (IP15’) 2015 Presenter:Yasuhiro Kohsaka, Shoya Ishihara, Tatsuki Kitayama
pH- / Temperature-responsive Materials Prepared from β-Amino Acid Ester Carrying Polymerizable Group The 13 th Asian Textile Conference 2015 Presenter:Yasuhiro Kohsaka, Yusuke Matsumoto, Tatsuki Kitayama
特許等知的財産
登録済特許 2価アルコール類、ポリカーボネート樹脂、ポリエステル樹脂、それらからなる成形体、および光学素子 ポリ擬ロタキサンの製造方法、架橋体の製造方法及びポリマーの回収方法 ロタキサン、架橋剤、架橋方法、架橋ポリマー及び架橋ポリマーの分解方法 Diol, and polycarbonate resin or polyester resin , PCT/JP2010/054467, WO 2010104199 A3 高分子化合物 α－（ハロメチル）アクリル化合物、重合体、重合体の製造方法、硬化物の製造方法及び硬化物 ポリ共役エステル及びその製造方法並びに硬化性組成物及びその硬化物 共役ジエン単位を有するポリマー及びその製造方法 フルオレン化合物及びその重合体並びにそれらの製造方法 フルオレン化合物の製造方法並びにフルオレン化合物の用途 フルオレン化合物およびその製造方法ならびにその前駆体および重合体 両末端反応性ポリマー、多価アクリル系ポリマー、架橋多価アクリル系ポリマー、環状ポリマー、及び環状グラフトポリマー スルフィド基を有するアリル位置換メタクリル酸エステルの製造方法 α－（置換メチル）アクリルアミド類及びその製造方法 α－（ヒドロキシメチル）アクリル化合物およびその製造方法、ならびにその重合体
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