聚氨酯/聚苯乙烯互穿聚合物网络的研究

互穿聚合物网络形态和力学性能的研究已有报道^1～3],但有关合成过程中分子量变化形态和性能的影响研究甚少。本文在动力学研究的基础上^4],用GPC、DSC和Instron万能机研究了聚氨酯/聚苯乙烯互穿聚合物网络(PU/PSt-IPN)的分子量,玻璃化转变温度和力能,考察了分子量与相分离点之间的关系。

Studies on Interpenetrating Polymer Networks of Polyurethane/Polystyrene

A series of interpenetrating polymer networks of polyurethane/polystyrene (PU/PSt-IPN) were synthesized by a simultaneous method. The. molecular weight,glass transition temperature and mechanical properties of the system were investigated by GPC, DSC and Instron Tester. The results show that the molecular weight of PSt decreases and its distribution becomes wider with increasing the ratio of PU in the system. During polymerization, the faster the molecular weight of the polymer in IPN increases,the earlier the phase separation of the system occurs. PU/PSt-IPN is an incompatible system. There are two rg's corresponding to the Tg's of the respective component polymers. The stiffness of the IPN increases with enhancing. DVB content and NCO/OH ratio or PSt ratio. The strain inbreak of the IPN is the largest at the composition ratio of 75/25.