In one aspect, the present disclosure encompasses polymerization systems for the copolymerization of CO2 and epoxides comprising 1) a catalyst including a metal coordination compound having a permanent ligand set and at least one ligand that is a polymerization initiator, and 2) a chain transfer agent having two or more sites that can initiate polymerization. In a second aspect, the present disclosure encompasses methods for the synthesis of polycarbonate polyols using the inventive polymerization systems. In a third aspect, the present disclosure encompasses polycarbonate polyol compositions characterized in that the polymer chains have a high percentage of —OH end groups and a high percentage of carbonate linkages. The compositions are further characterized in that they contain polymer chains having an embedded polyfunctional moiety linked to a plurality of individual polycarbonate chains.
在一个方面,本发明公开了用于
二氧化碳和
环氧化物共聚的聚合体系,该体系包括:1)催化剂,包括具有永久配位体的
金属配位化合物和至少一种作为聚合
引发剂的配位体;2)链转移剂,该链转移剂具有两个或两个以上可引发聚合的位点。第二方面,本公开包括使用本发明聚合体系合成聚
碳酸酯多元醇的方法。第三方面,本公开包括聚
碳酸酯多元醇组合物,其特征在于聚合物链具有高比例的 -OH 端基和高比例的
碳酸酯链节。这些组合物的进一步特征在于,它们含有与多个单独的聚
碳酸酯链连接的嵌入式多官能团的聚合物链。