Cyclo-depolymerizations of polycarbonates in solution: Use of the macrocyclic oligomers obtained in entropically-driven ring-opening polymerizations and copolymerizations to give carbonate–carbonate and carbonate–carboxylate ester copolymers
作者:Philip Hodge、Stephen D. Kamau、Abderrazak Ben-Haida、Richard T. Williams
DOI:10.1016/j.reactfunctpolym.2012.07.004
日期:2012.11
carbonate) and two poly(alkylene carbonate)s to give, in each case, mixtures of macrocyclic oligomers (MCOs). The aromatic carbonate was less reactive than the aliphatic carbonates. Using various catalysts small-scale entropically-driven ring-opening polymerizations (ED-ROPs) of the MCOs reformed the original polymers. Tetra-n-butylammonium tetraphenylborate was the most generally useful catalyst of
我们报道了在每种情况下,聚(双酚A碳酸酯)和两种聚(碳酸亚烷基酯)溶液的环解聚反应,得到大环低聚物(MCO)的混合物。芳族碳酸酯的反应性低于脂族碳酸酯。使用各种催化剂,MCO的小规模熵驱动开环聚合(ED-ROP)重整了原始聚合物。四苯基硼酸四正丁基铵是所研究那些中最普遍使用的催化剂。在230°C下不添加催化剂的情况下,对含脂肪族碳酸酯的MCO进行热ED-ROP。为了探究在共聚物合成中扩展使用ED-ROP的可能性,研究了含碳酸酯的MCO相互之间以及与含羧酸酯的MCO的共聚反应。这些以高收率提供了一系列共聚物,其中13 C NMR光谱法显示其中一些具有随机序列的重复单元。这种含有碳酸酯键的共聚物的合成方法具有用于合成聚合物库的潜力。