Nishida Takenori, Satoh Kotaro, Nagano Shusaku, Seki Takahiro, Tamura Masazumi, Li Yingai, Tomishige Keiichi, Kamigaito Masami
Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.
Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, 2-12-1-H120 Ookayama, Meguro-ku, Tokyo 152-8550, Japan.
ACS Macro Lett. 2020 Aug 18;9(8):1178-1183. doi: 10.1021/acsmacrolett.0c00479. Epub 2020 Jul 31.
Carvone, a naturally abundant chiral cyclic α,β-unsaturated carbonyl compound, was chemically transformed into cyclic -methylene conjugated dienes. The -methylene group had high reactivity in cationic polymerization and was efficiently polymerized in a controlled manner via regioselective 1,4-conjugated additions using initiating systems effective for living cationic polymerization of vinyl ethers. The obtained polymers with 1,3-cyclohexenyl units and tetra-substituted olefins in the main chain showed high glass transition temperatures over 110 °C. The chiral monomer underwent stereospecific polymerization to result in polymers with low solubility and weak packing of the rigid main chain in the lamellar layers. The racemic mixture resulted in soluble amorphous polymers, which were subsequently hydrogenated into cycloolefin polymers with enhanced thermal properties.
香芹酮是一种天然丰富的手性环状α,β-不饱和羰基化合物，可通过化学方法转化为环状亚甲基共轭二烯。亚甲基在阳离子聚合反应中具有高反应活性，并通过使用对乙烯基醚活性阳离子聚合有效的引发体系，通过区域选择性1,4-共轭加成以可控方式高效聚合。所得主链含有1,3-环己烯基单元和四取代烯烃的聚合物显示出超过110°C的高玻璃化转变温度。手性单体进行立体定向聚合，生成在层状结构中刚性主链溶解性低且堆积松散的聚合物。外消旋混合物则生成可溶性无定形聚合物，随后将其氢化成为热性能增强的环烯烃聚合物。
