Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
ACS Macro Lett. 2022 Dec 20;11(12):1331-1335. doi: 10.1021/acsmacrolett.2c00594. Epub 2022 Nov 10.
Structurally controlled high-molecular-weight (HMW) polystyrenes (PSts) and block copolymers consisting of HMW PSt segments were successfully synthesized by emulsion organotellurium-mediated radical polymerization (TERP). The hydrophilicity of the organotellurium group of TERP chain transfer agents (CTAs) was important for success, and CTAs and with di- and tetraethylene glycol units were suitable. By using and and using hexadecyltrimethylammonium bromide (CTAB) as the surfactant, PSts with MWs over 1 million and with low dispersity ( < 1.6) were synthesized with >96% monomer conversion. Because of the high monomer conversion, high end-group fidelity, and rapid monomer diffusion to polymer particles, HMW block copolymers with low dispersity were successfully synthesized by adding a second monomer after converting the first monomer without isolating the macroinitiators. Despite recent developments in reversible-deactivation radical polymerization (RDRP), the synthesis of HMW polymers, particularly PSts and block copolymers, has been a formidable challenge. This method provides a valuable route for fabricating polymer materials based on HMW PSts.
通过乳液有机碲介导的自由基聚合（TERP）成功合成了结构控制的高分子量（HMW）聚苯乙烯（PSt）和由 HMW PSt 段组成的嵌段共聚物。TERP 链转移剂（CTA）中有机碲基团的亲水性对于成功至关重要，具有二甘醇和四甘醇单元的 CTA 和 是合适的。使用 和 ，并使用十六烷基三甲基溴化铵（CTAB）作为表面活性剂，以超过 96%的单体转化率合成了分子量超过 100 万且分散度低（<1.6）的 PSt。由于高单体转化率、高端基保真度和单体向聚合物颗粒的快速扩散，在不分离大分子引发剂的情况下添加第二种单体后，成功合成了低分散度的 HMW 嵌段共聚物。尽管最近在可逆失活自由基聚合（RDRP）方面取得了进展，但 HMW 聚合物，特别是 PSt 和嵌段共聚物的合成仍然是一个艰巨的挑战。该方法为基于 HMW PSt 的聚合物材料的制备提供了有价值的途径。
