中文摘要：

对剪切场作用下的全同聚丙烯/弹性体乙烯-辛烯共聚物（iPP/PEcO）的共混物结晶行为进行研究,结果表明,剪切使得iPP球晶密度增加,微晶和片晶均发生取向,且片晶取向明显;片晶取向度随共混物中PEcO含量的增加而增大,而微晶取向度随PEcO含量的增加而减小;强剪切诱导出现纤维状结晶形态.利用同步辐射（SAXS）技术对共混物在剪切场下的等温结晶行为进行研究,结果表明,随结晶的进行长周期呈现先减少而后固定的趋势;高剪切速率缩短了结晶诱导时间,加快了共混物中结晶部分的结晶动力学过程.

英文摘要：

Crystallization behavior of sheared iPP/PEcO blends were investigated via small-angle X-ray scattering（SAXS）,Wide-angle X-ray scattering（WAXS） and Polarizing Optical Microscope（POM）.The results indicate that the morphology of sphere crystal obviously changes with PEcO content in the blend.Shear not only increases the density of spherulite but also induces the formation of fiber-like crystal.The lamellar orientation and crystallite orientation were affected by shear,especially the orientation of lamellae was more obvious than that of crystallites.The degree of lamellar orientation enhances with the increasing amount of elastomer,whereas the degree of crystallite orientation decreases with the increasing of elastomer.In situ synchrotron SAXS data shows that the long period of lamellae decreases at the early period of crystallization and afterwards remains fixed.The high shear intensity decreases the induction time for crystallization and obviously accelerates the process of crystallization kinetics.The evolvement of crystalline structure and the degree of orientation differences between crystallite and lamellae of the blend crystallization under shear may support the mesomorphic phase concept of flexible polymer crystallization process proposed by Strobl.Based on all the analyses a relatively stable mesomorphic structure is thought to have formed before shear is composed and the shear-induced initial states of polymer play an important role in affecting the crystallization behavior.