中国塑料 ›› 2016, Vol. 30 ›› Issue (03): 16-21 .DOI: 10.19491/j.issn.1001-9278.2016.03.003

• 材料与性能 • 上一篇    下一篇

高温熔融对PP/EPR/PE-UHMW分子链扩散作用以及流变和结晶性能的影响

谢安准   

  1. 四川大学
  • 收稿日期:2015-10-08 修回日期:2015-12-03 出版日期:2016-03-26 发布日期:2016-03-26

Diffusion Effect of Melting at High Temperature on PP/EPR/PE-UHMW and Its Influence on Rheological and Crystallization Behavior

  • Received:2015-10-08 Revised:2015-12-03 Online:2016-03-26 Published:2016-03-26

摘要: 采用一种简便易行的方法使高度缠结的超高相对分子质量聚乙烯(PE-UHMW)与乙丙橡胶(EPR)的分子链得到有效的扩散,并最终将EPR/PE-UHMW预混物与聚丙烯(PP)共混形成PP/EPR/PE-UHMW三元共混物。并研究了该三元共混物的流变性能和结晶性能。结果表明,在预混物体系中,经历高温熔融处理后,流变曲线出现不同于一般EPR材料的难松弛结构的低频平台区,说明PE-UHMW与EPR分子链相互扩散形成长分子链缠结结构;其缠结结构在PP/EPR/PE-UHMW共混物中减慢了PP基体流变曲线低频平台区出现的趋势,限制了EPR向PP基体的扩散; EPR与PE-UHMW分子链之间的相互扩散,对高度缠结的PE-UHMW具有增塑作用,导致PE-UHMW结晶温度下降和结晶度上升;二元预混物添加进入PP基体中,促使PP多重熔融现象的发生。

关键词: 聚丙烯, 乙丙橡胶, 聚乙烯, 高温熔融

Abstract: A simple method was used to promote the diffusion of highlyentangled molecular chains of ultra high molecular weight polyethylene (PE-UHMW) and ethylene propylene rubber(EPR) leading to blends of EPR/PE-UHMW, which was further mixed with polypropylene (PP) forming PP/EPR/PE-UHMW ternary blends. The blends were characterized by rheological measurement and differential scanning calorimeter (DSC). The rheological tests displayed a long relaxation mechanism occurring in the lowfrequencies region. The interentanglement structure restricted the diffusion of EPR into PP matrix. DSC showed that the plasticization of PE-UHMW resulted in decreasing in crystallization temperature and increasing indegree of crystallinity. The addition of EPR/PE-UHMW blend to PP matrix caused a multiple melting behavior of PP.

Key words: polypropylene, ethylene propylene rubber, polyenthylene, high-temperature melting