阴离子嵌段共聚的交联聚苯乙烯的网络链长多分散性与网络结构非均一性

Polydispersity of Network Chain Length and the Heterogeneity of the Anionic Block Copolymerized Styrene-Divinylbenzene Networks

用链长分布不同的活性聚苯乙烯子聚物与二乙烯基苯进行阴离子嵌段共聚,合成了一系列两相模型交联网络。以作者等提出的方法测定了所合成网络的结构非均一因子Z。实验测定的网络结构非均一因子Z与交联前聚苯乙烯活性链的分子量分布宽度指数d之间有平行的相应变化规律,表明所给予的非均一因子Z的物理意义是合理的。同时说明,子聚物链长分布较宽时,在网络的高交联区中除了二乙烯基苯外,还有一些对溶胀无贡献的子聚物以悬挂链的形式存在。

A number of model networks were prepared by anionic block copolymerization of divinylbenzene with various living polystyrene precursors having different chain length distribution. The tructural heterogeneity factor Z of the network was determined by using the method proposed by the authors. The variation of the experimentally determined heterogeneity factor Z of these model networks is in parallel with the inhomogeneity indexes of the living polystyrene chains before crosslinking. This fact indicates the physical meaning incorporated to the heterogeneity factor Z is reasonable. The data also demonstrated that some polystyrene precursors with only one living chain end are connected to the poly-divinylbenzene nodules as pendant chains contributing nothing to the swelling of the whole network.