【摘要】 本文发展了一种高分子量聚合物熔融体的应力诱导结晶结构形态模型,它是由微晶聚集体(以下简称微区)-高分子链组网和缠结网的网络结构组成。基于上述模型,把二种网中的单个链组作为独立的统计单元和形变单元,计算了二种网中单个链组的末端距分布函数,进一步计算了二种网和总网的形变自由能。在此基础上,讨论了诱导结晶结晶机理和自增强聚合物网络自由能的依赖性,并着重地研究了超拉伸高聚物的起始熔点拉伸比间的关系。用超高分子量聚乙烯膜和超取向高密度聚乙烯纤维的起始熔点和拉伸比的实验数据进行处理,得到理论予期的近似直线关系,初步验证了聚合物网应力诱导结晶理论。更多还原

【Abstract】 A structure model of networks for UHMWPE which is composed of the two kinds of constituent Chains in these networks was proposed, and their probability distribution functions of the end-to-and vector were calculated by the present method. Based on the above model of networks for UHMWPE and the mechanism of large deformation the total free energy of stress-induced crystallization networks was calculated. Using the equation of the total free energy of deformation, the dependence of incipient melting temperature on extension ratio for polymer networks with stress-induced crystallization was derived.A series of expected lines were obtained, it shows that the thermodynamic theory of stres-induced crystalliization agrees with experimental results.更多还原