剪切场下聚丙烯柱晶的形成与机理研究回顾(英文)  

Review of shear induced crystallization of isotactic polypropylene based materials

作　　者：董侠[1] 孙同臣[1] 孟昆[1] 张成贵[1] 韩志超[1] 

机构地区：[1]中国科学院化学研究所高分子物理与化学国家重点实验室,北京100190

出　　处：《西安工程大学学报》2009年第2期41-49,共9页Journal of Xi’an Polytechnic University

基　　金：Supported of by NSFC (20574081,50773087,20490220)

摘　　要：分析、对比、讨论了聚丙烯及其弹性体共混体系和纳米粘土复合材料体系在剪切场中的柱晶形成形貌和机理.对近期所作的剪切诱导结晶工作进行了回顾与总结.剪切场下缠结的高分子链被拉伸并形成柱晶的晶核是剪切诱导结晶的首要条件,柱晶的形貌受材料体系、相分离过程、纳米填料的介观网络结构形成与分散状况及剪切条件的影响.The mechanism and morphology of shear induced crystallization of isotactic polypropylene （iPP） in its blends or composites were analyzed, compared and discussed in this work. For pure iPP, crystalline structure of cylindrites can be observed easily under very low shear rate. But for iPP/poly （ethylene-co-octene） （PEOc） blends, cyllndrites were observed after shear in the very late stage of phase separation only when the shear rate was large enough. The morphologies of cylindrites were multi-formed and different from the pure iPP because PEOc is an elastermer and the PP/PEOc blend system is phase separated. For PP/OMMT （organo-montmorillonite, clay） composites the fillers could form mesescale network in the polymer matrix. The effect of shear on the heterogeneous nucleation, cylindrites formation and morphology of spherulltes were discussed and compared with pure iPP and PP/ PEOc blend. The clay content is also a very important parameter in the crystallization behavior. For all three systems the mecbanism of shear induced cylindrites was initiated by the structure of the entangled polymer chain network which formed bunddled core nuclei.

关 键 词：剪切诱导结晶 聚丙烯 共混 纳米复合材料 

分 类 号：TB383[一般工业技术—材料科学与工程]