Chen Dian-Feng, Bernsten Simone, Miyake Garret M
Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States.
Macromolecules. 2020 Oct 13;53(19):8352-8359. doi: 10.1021/acs.macromol.0c01367. Epub 2020 Sep 1.
Organocatalyzed photoredox radical ring-opening polymerization (rROP) of vinylcyclopropanes (VCPs) is employed for the synthesis of polymers with controlled molecular weight (MW), dispersity, and composition. Herein, we report the study on the rROP of a variety of VCP monomers bearing diverse functional groups (such as amide, alkene, ketal, urea, hemiaminal ether, and so on) under organocatalyzed conditions with varying light sources and temperature. Notably, VCP monomers bearing natural product functionality or their derivatives can be polymerized in a controlled manner to produce poly(VCPs) with predictable MW, low dispersity, tunable composition, high thermal stability, and tailored glass transition temperature ( ), ranging 39 to 107 °C. Lastly, successful "grafting through" synthesis of molecular brush copolymers containing 1.0 or 5.0 kDa polydimethylsiloxane (PDMS) side chains from readily accessible EtVCP-PDMS macromonomers further demonstrates the robustness of this organocatalyzed photoredox rROP.
乙烯基环丙烷（VCPs）的有机催化光氧化还原自由基开环聚合（rROP）用于合成具有可控分子量（MW）、分散度和组成的聚合物。在此，我们报道了在有机催化条件下，使用不同光源和温度，对多种带有不同官能团（如酰胺、烯烃、缩酮、脲、半胺基醚等）的VCP单体进行rROP的研究。值得注意的是，带有天然产物官能团的VCP单体或其衍生物能够以可控方式聚合，生成具有可预测分子量、低分散度、可调组成、高热稳定性以及39至107°C范围内定制玻璃化转变温度（ ）的聚（VCPs）。最后，从易于获得的EtVCP-PDMS大分子单体成功“接枝合成”含1.0或5.0 kDa聚二甲基硅氧烷（PDMS）侧链的分子刷共聚物，进一步证明了这种有机催化光氧化还原rROP的稳健性。
