Syntheses of New Functionalized Materials by Radical Ring-Opening Polymerization and Their Evaluation of Physical Properties

我们研究了市售乙烯基单体与自由基开环可聚合单体的共聚，以开发新的功能化材料，包括聚合物骨架中的酯基、醚基、酮基等官能团。新自由基开环可聚合单体的合成：(1)采用2,2-二苯基-4-亚甲基-1,3-二恶烷（DPMD）自由基聚合，定量消除二苯甲酮，得到聚酮。(2)亚甲基环丁烷进行乙烯基开环聚合，而乙烯基环丁烷进行自由基开环聚合得到聚1,6-己-2-烯。(3)乙烯基硫烷发生自由基聚合，在碳原子与硫原子之间的键处开环，而在乙烯基硫烷聚合过程中，氧环的碳-碳键发生断裂。(4)制备了含苯基、酯基、氰基等官能团的乙烯基环丙烷，均发生了自由基开环聚合。共聚：(1)将乙烯基环氧乙烷与乙烯进行共聚，得到以乙烯基醚为主体的聚乙烯。(2) DPMD与乙烯的共聚得到了在聚合物主链中含有酮和醚基团的聚乙烯。(3)将DPMD与苯乙烯共聚，得到了含酮基的聚苯乙烯。此外，通过改变DMPD的投料比，可以任意控制聚合物中酮基的含量。(4) DPMD还可以与其他乙烯基单体如n -乙烯基-2吡罗烷酮、醋酸乙烯和甲基丙烯酸甲酯等共聚生成相应的共聚物，包括聚合物主链中的酮基。对这些共聚物物理性质的进一步研究正在进行中。

We have investigated the copolymerization of commercially available vinyl monomers with radical ring-opening polymerizable monomers in order to develop new functionalized materials including the functional groups such as the ester group, ether group, and ketone group in the polymer backbone.1. Syntheses of New Radical Ring-Opening Polymerizabel Monomers: (1) Radical polymerization of 2,2-Diphenyl-4-methylene-1,3-dioxolane (DPMD) was carried out to obtain poly(ketone) with a quantitative elimination of benzophenone. (2) Methylenecyclobutane underwent vinyl polymerization without ring-opening, whereas vinylcyclobutane did radical ring-opening polymerization to afford poly(1,6-hex-2-ene). (3) Vinylthiirane underwent radical polymerization with the ring-opening at the bond between carbon and sulfur atom, although carbon-carbon bond of the oxirane ring was cleaved in the polymerization of vinyloxirane. (4) Vinylcyclopropanes bearing functional groups such as the phenyl group, ester group, and cyano group were prepared, and all of them were found to undergo radical ring-opening polymerization.2. Copolymerization: (1) Copolymerization of vinyloxirane with enhylene was carried out to obtain polyethylene bearing the vinyl ether groups in the polymer backbone. (2) Copolymerization of DPMD with enhylene afforded polyethylene containing the ketone and ether groups in the polymer backbone. (3) Copolymerization of DPMD with styrene was carried out to obtain polystyrene including the ketone groups in the polymer backbone. furthermore, the content of the ketone group in the polymer can be arbitrarily controlled by the change of DMPD's feed ratio. (4) DPMD can copolymerize also with other vinyl monomers such as N-vinyl-2 pyrrolidone, vinyl acetate, and methyl methacrylate to yield the corresponding copolymers including the ketone groups in the polymer backbone. Further investigation on physical propaties of these copolymers is in progress now.