To avoid sequence bias in the chain growth process of multicomponent periodic polymers, we reported an indirect method for the synthesis of strictly periodic polymers using nonpolar monomers. Using 1,1-diphenylethylene (DPE) as the comonomer, the precise sequence was achieved through living anionic polymerization (LAP) and hydrogenation. Four dienes (isoprene (Ip), 2,3-dimethylbuta-1,3-diene (DMBD), 2,3-diphenylbutadiene-1,3-diene (DPB), and 1-phenyl-1,3-butadiene (1-PB)) and an olefin with cyclic tension 1-cyclobutylvinylbenzene (CBVB) were copolymerized with DPE to prepare the alternating precursors. The periodic sequences of DPE–styrene–propylene (pd-DSP), DPE–propylene–propylene (pd-DPP), DPE–ethylene–styrene (pd-DES), DPE–styrene–styrene (pd-DSS) and DPE–ethylene–styrene–styrene (pd-DESS) were successfully synthesized with hydrogenation of these alternating precursors, and the nonpolar olefin units were successfully introduced into the periodic polymer. The results showed that the modification of the backbone carbon framework structure caused a consistent change in the thermal properties of the polymers. Moreover, the steric hindrance and arrangement density of the side chain substituents could significantly affect the performance of the periodic copolymers. This study provides a feasible method for the synthesis of non-polar periodic copolymers with precise periodic arrangements.

中文翻译：

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基于阴离子交替共聚反应的周期性聚烯烃的合成


为了避免多组分周期性聚合物链生长过程中的序列偏差，我们报道了一种使用非极性单体合成严格周期性聚合物的间接方法。以 1,1-二苯乙烯 （DPE） 为共聚单体，通过活阴离子聚合 （LAP） 和氢化获得精确的序列。将四种二烯（异戊二烯 （Ip）、2,3-二甲基丁-1,3-二烯 （DMBD）、2,3-二苯基丁二烯-1,3-二烯 （DPB） 和 1-苯基-1,3-丁二烯 （1-PB）） 和一种具有环状张力的烯烃 1-环丁基乙烯基苯 （CBVB） 与 DPE 共聚，制备交替前驱体。通过这些交替前驱体的加氢，成功合成了DPE-苯乙烯-丙烯（pd-DSP）、DPE-丙烯-丙烯（pd-DPP）、DPE-乙烯-苯乙烯（pd-DES）、DPE-苯乙烯-苯乙烯（pd-DSS）和DPE-乙烯-苯乙烯-苯乙烯（pd-DESS）的周期序列，并将非极性烯烃单元成功引入周期性聚合物中。结果表明，主链碳框架结构的改性导致聚合物的热性能发生持续变化。此外，侧链取代基的空间位阻和排列密度会显着影响周期共聚物的性能。本研究为合成具有精确周期排列的非极性周期共聚物提供了一种可行的方法。