Changes of crystallinity and spherulite morphology in isotactic polypropylene after rolling and heat treatment  

作　　者：Juan Jia Weimin Mao Dierk Raabe 

机构地区：[1]School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China [2]Max-Planck-Institut fur Eisenforschung, Max-Planck-Str. 1, Düsseldorf 40237, Germany

出　　处：《Journal of University of Science and Technology Beijing》2008年第4期514-520,共7页北京科技大学学报（英文版）

摘　　要：The spherulite morphology of the rolled and subsequent heat-treated isotactic polypropylene （iPP） was observed by polarized microscopy, and the crystallinity evolution of materials was also measured by the wide angle X-ray scattering （WAXS）. Rolling led to the oblate spherulites in the deformed iPP samples. The sheared crystalline lamellae broke apart into sets of crystalline blocks during rolling. As a result, the crystallinity of the iPP samples was greatly reduced during deformation, which induced the unclear spherulites and spherulite boundaries. Subsequent heat treatment resulted in the strong reerystallization of the rolled iPP samples. But the recrystaUizatinn in this work only meant the rearrangement of the macromolecule along the unbroken crystalline lamellae and the existing small crystalline blocks in the deformed spherulites. Heat treatment did not change the shape of the spherulites formed during deformation. The recrystallization also resulted in very clear spherulites and spherulite boundaries.The spherulite morphology of the rolled and subsequent heat-treated isotactic polypropylene （iPP） was observed by polarized microscopy, and the crystallinity evolution of materials was also measured by the wide angle X-ray scattering （WAXS）. Rolling led to the oblate spherulites in the deformed iPP samples. The sheared crystalline lamellae broke apart into sets of crystalline blocks during rolling. As a result, the crystallinity of the iPP samples was greatly reduced during deformation, which induced the unclear spherulites and spherulite boundaries. Subsequent heat treatment resulted in the strong reerystallization of the rolled iPP samples. But the recrystaUizatinn in this work only meant the rearrangement of the macromolecule along the unbroken crystalline lamellae and the existing small crystalline blocks in the deformed spherulites. Heat treatment did not change the shape of the spherulites formed during deformation. The recrystallization also resulted in very clear spherulites and spherulite boundaries.

关 键 词：isotaetic polypropylene （iPP） ROLLING heat treatment X-ray diffraction CRYSTALLINITY SPHERULITES 

分 类 号：TQ325.14[化学工程—合成树脂塑料工业]