Luk Sharmaine B, Maríc Milan
Department of Chemical Engineering, McGill University, 3610 Rue University, Montréal, Québec H3A 0C5, Canada.
ACS Omega. 2021 Feb 11;6(7):4939-4949. doi: 10.1021/acsomega.0c05992. eCollection 2021 Feb 23.
Biobased farnesene (Far) was polymerized by nitroxide-mediated polymerization in miniemulsions using two different alkoxyamine initiators, the SG1-based and succinimidyl-modified BlocBuilder (NHS-BB) and Dispolreg 007 (D7). Stable emulsions were observed after 30 h of reaction at 90 °C, where NHS-BB-initiated systems resulted in smaller particles (∼300 nm) than using D7 (∼400 nm). Successful chain extension of the poly(Far) macroinitiators (24,500-39,700 g mol) with styrene were achieved using 15 wt % surfactant relative to monomer concentration. Compartmentalization effects were not observed in these emulsions as the polymerization rate was still much slower compared to the bulk, even though -averaged particle sizes were around 300-400 nm. Finally, all biobased diblock copolymers were synthesized by chain-extending poly(Far) macroinitiators with isobornyl methacrylate (iBOMA), where the D7 initiator showed more effective chain extension (less unreacted macroinitiator) than NHS-BB.
采用两种不同的烷氧基胺引发剂，即基于SG1的琥珀酰亚胺基修饰的嵌段构建剂（NHS-BB）和Dispolreg 007（D7），通过细乳液中的氮氧自由基介导聚合反应使生物基法尼烯（Far）发生聚合。在90℃反应30小时后观察到稳定的乳液，其中NHS-BB引发的体系产生的颗粒（约300nm）比使用D7（约400nm）时更小。相对于单体浓度，使用15wt%的表面活性剂成功实现了聚（Far）大分子引发剂（24,500 - 39,700 g/mol）与苯乙烯的链增长。尽管平均粒径约为300 - 400nm，但由于聚合速率与本体相比仍然慢得多，在这些乳液中未观察到区室化效应。最后，通过用甲基丙烯酸异冰片酯（iBOMA）使聚（Far）大分子引发剂进行链增长合成了所有生物基二嵌段共聚物，其中D7引发剂比NHS-BB表现出更有效的链增长（未反应的大分子引发剂更少）。
