聚合物在压力下的流动诱导结晶

发布时间：2018-03-27 15:10

  本文选题：压力　切入点：流动场　出处：《高分子通报》2017年10期

【摘要】：流动诱导聚合物结晶研究很少在压力场下开展,其原因是压力下流动诱导聚合物结晶对实验设备要求较高。然而,实际加工中不仅存在流动场,还有压力场。为此,作者课题组利用自制的装置对压力下流动诱导聚合物结晶开展了系统研究,发现其结晶行为与常压的流动诱导结晶有较大差别。等规聚丙烯(iPP)在压力和剪切场下可形成独特取向球形晶体形态。在短时间内(30min),iPP片晶可快速增厚,形成熔点接近平衡熔点的厚片晶(近180℃),其原因是在压力和流动场协同作用下,片晶增厚活化能快速减小。同时,从研究结果也获得了添加β成核剂的iPP体系在压力和流动场下形成β晶的窗口条件。对聚乳酸(PLA)的研究也发现了相似的片晶快速增厚规律。另外,在压力和流动场下,可直接从PLA熔体中获得可增韧PLA的β晶。研究成果为实际加工中的聚合物形态结构调控提供了理论和实验依据。
[Abstract]:The research of flow-induced polymer crystallization is seldom carried out under pressure field, because the flow induced polymer crystallization under pressure requires high experimental equipment. However, there is not only flow field but also pressure field in practical processing. The author's team has carried out a systematic study of flow-induced polymer crystallization under pressure by using a self-made device. It is found that the crystallization behavior of IPP is different from that of fluid-induced crystallization under atmospheric pressure. Ipp can form a unique oriented spherical crystal form under the pressure and shear field. In a short period of time, the IPP wafer can be rapidly thickened. The formation of thick wafer crystals with melting point close to equilibrium melting point (nearly 180 鈩，

本文编号：1672049