离子液体支载稀土催化剂催化2,2-二甲基-三亚甲基碳酸酯均聚及其与ε-己内酯的共聚

Ring-Opening Polymerization of 2,2-Dimethyltrimethylene Carbonate and Its Copolymerization with ε-Caprolactone by Ionic Liquid-Supported Rare Earth Metal Complex Catalysts

首次合成了离子液体支载稀土催化剂,并探讨了其催化2,2-二甲基-三亚甲基碳酸酯(DTC)均聚及其与ε-己内酯(ε-CL)的共聚,结果表明该新型催化剂能有效地催化DTC的均聚及其与ε-CL的共聚.研究了不同稀土以及加料顺序等反应条件对聚合的影响,发现轻稀土的催化活性比重稀土高,其中离子液体支载La催化剂的催化活性最高,而通过控制不同的加料顺序可以制备DTC和ε-CL的无规及嵌段共聚物.对共聚物结构进行了表征.

Homopolymerization of 2,2-dimethyhrimethylene carbonate and its copolymerization with ε-caprolactone （ε-CL） catalyzed by ionic liquid-supported rare earth catalysts were investigated for the first time. The results indicated that this novel catalyst is effective for the homopolymerization and copolymerization. Of all the rare earth catalysts prepared, LaCl3 showed the highest catalytic activity and can be used to prepare poly（2,2- dimethyhrimethylene carbonate） with a viscosity average molecular weight of 3.61 × 10^4 and a yield over 88% under mild conditions of ε-CL/La molar ratio = 200 and 60 ℃ in toluene. Moreover, both random and block copolymers can be prepared by changing the feed sequence with this catalyst only when ε-CL was polymerized first. When 2,2-dimethyhrimethylene carbonate was polymerized first, only homopolymer can be prepared. The copolymers were characterized by 1H NMR.