Crystallization mechanism of polymer

研究了聚合物结晶的形成机理，重点研究了成核前的结晶诱导期。本工作可分为以下四个方面。(1)聚合物结晶准备过程中的结构形成：我们利用实验室研制的超温跳变装置，直接观察到了等规聚丙烯(IPP)从熔融状态到介晶态的转变过程。(2)剪切流动下的聚合物结晶：我们利用时间分辨去偏振光散射、小角X射线散射、小角中子散射和广角中子散射技术，研究了剪切流作用下iPP结晶过程中所谓的石灰串结构的结构形成过程。(3)取向玻璃聚合物的结晶机理：为了阐明所谓长周期的形成机理，我们采用了时间分辨的去偏振光散射、小角X射线散射、小角中子散射和广角中子散射技术。我们用时间分辨广角散射技术研究了取向聚对苯二甲酸乙二酯的结晶过程。(4)研究了棒状聚合物和柔性聚合物混合体系中相分离对聚合物结晶的影响，阐明了聚合物结晶过程中的耗尽效应。

We have studied formation mechanism of polymer crystallization, focusing our attention on induction period of crystallization before nucleation. This work can be classified into the following four subjects.(1)Structural formation in preparatory process of polymer crystallization : We have directly observed transformation process from molten state to mesomorphic state of isotactic polypropylene(iPP) using super temperature jump apparatus developed by our laboratory.(2)Polymer crystallization under shear flow : We have evaluated structure formation process of so-called shishi-kebab structure in crystallization of iPP under shear flow, using time resolved depolarized light scattering, small angel X-ray scattering, small angel neutron scattering and wide angel neutron scattering techniques.(3)Crystallization mechanism of polymers from oriented glass : In order clarify the mechanism of formation of so-called long period, we have studied crystallization process of oriented poly (ethylene terephthalate) using a time resolved wide angel scattering technique(4)We investigated effects of phase separation on polymer crystallization in mixture of rod-like polymers and flexible polymers and clarified depletion effects in polymer crystallization.