CAJ | 학술논문

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.
분석、대비、토론료취병희급기탄성체공혼체계화납미점토복합재료체계재전절장중적주정형성형모화궤리.대근기소작적전절유도결정공작진행료회고여총결.전절장하전결적고분자련피랍신병형성주정적정핵시전절유도결정적수요조건,주정적형모수재료체계、상분리과정、납미전료적개관망락결구형성여분산상황급전절조건적영향.
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, cylindrites 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 mesoscale network in the polymer matrix. The effect of shear on the heterogeneous nucleation, cylindrites formation and morphology of sphemlites 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 mechanism of shear induced cylindrites was initiated by the structure of the entangled polymer chain network which formed bunddled core nuclei.