聚乙烯晶体形态及排列方向对其力学性能的影响  

Effect of Crystal Morphology and Alignment Direction on Mechanical Performance of Polyethylene

作　　者：张大合 聂敏[2] 石艳[1] ZHANG Da-he;NIE Min;SHI Yan(Sichuan Provincial Key Lab of Process Equipment and Control,Sichuan University of Science&Engineering,Zigong 643002,China;State Key Laboratory of Polymer Materials Engineering,Polymer Research Institute of Sichuan University,Chengdu 610065,China)

机构地区：[1]过程装备与控制工程四川省高校重点实验室,四川理工学院,四川自贡643002 [2]高分子材料工程国家重点实验室,四川大学高分子研究所,四川成都610065

出　　处：《塑料工业》2021年第1期30-33,共4页China Plastics Industry

基　　金：过程装备与控制工程四川省高校重点实验室开放基金(GK201720)。

摘　　要：采用模压和流延成型工艺,制备了具有各向同性球晶和各向异性串晶结构的聚乙烯(PE)样品,系统研究了晶体形态及串晶排列对PE强度和蠕变性能的影响。结果表明,PE的性能不仅与晶体形态相关,还取决于外加载荷与串晶排列的方向。随着外加载荷与串晶排列方向夹角的增大,有效晶片间的系带分子tie分子链数目减少,材料的破坏形式从片晶分离转变为片晶滑移,使得样品的强度和耐蠕变性能显著降低。Molding and casting processes were used to prepare polyethylene(PE)samples with isotropic spherulites and anisotropic shish-kebab structures and the effects of crystal morphology and arrangement on the strength and creep properties were systematically studied.The results show that the performance of PE is not only related to the crystal morphology,but also depends on the angle between the applied load and the shish kebab.With the increasing angle,the effective number of tie molecular chains decrease,and the failure mode of the material changes from lamella separation to crystal slip,which significantly reduces the strength and creep resistance of the sample.

关 键 词：聚乙烯 取向 排列方向 蠕变 强度 

分 类 号：TQ325.12[化学工程—合成树脂塑料工业]