A novel synthetic method for hyperbranched polymers is reported. A cobalt catalyst previously developed in our group promotes the catalytic alkyne [2 + 2 + 2] cycloaddition polymerization of aromatic diynes with internal alkynes, which proceeds without gelation or production of insoluble materials to give the corresponding soluble polymer in good yields. The method is reproducible, and the polymerization behavior can readily be predicted by the results of model reactions. Thus, the molecular weight and a degree of branching (DB) of the resulting polymer can be controlled by selecting the internal alkyne monomer and its loading amount. The occurrence of effective endcapping reaction was confirmed by degradation of the polymer derived from a diyne bearing a silyl ether linker, and a high DB of more than 0.5 was obtained.

报道了一种新的超支化聚合物的合成方法。先前在我们小组中开发的钴催化剂可促进芳族二炔与内部炔的催化炔[2 + 2 + 2]环加成聚合反应，该过程无需胶凝或产生不溶物即可进行，从而以高收率得到相应的可溶性聚合物。该方法是可重现的，聚合反应行为可以通过模型反应的结果轻松预测。因此，可以通过选择内部炔烃单体及其负载量来控制所得聚合物的分子量和支化度（DB）。通过衍生自带有甲硅烷基醚连接基的二炔的聚合物的降解证实了有效的封端反应的发生，并且获得了大于0.5的高DB。