相对分子质量对β晶型等规聚丙烯性能的影响  

Effect of Relative Molecular Weight on Properties of β-Form Isotactic Polypropylene

作　　者：董穆[1] 张丽英[1] 徐凯[1] 吕芸[1] 张师军[1] 

机构地区：[1]中国石油化工股份有限公司北京化工研究院,北京100013

出　　处：《中国塑料》2012年第4期61-65,共5页China Plastics

摘　　要：利用熔体流动速率来反映等规聚丙烯(IPP)的相对分子质量,在添加自制β成核剂的条件下通过力学性能测试、差示扫描量热仪以及X射线衍射仪研究了相对分子质量对β晶型等规聚丙烯(β-PP)热行为、晶型组成和力学性能的影响。结果表明,加入β晶型成核剂后,IPP结晶温度、热变形温度均增加10℃左右,β晶型相对含量增加至60%～70%;相对分子质量较高的β-PP冲击强度提高一倍以上,相对分子质量较低的β-PP冲击性能改善有限;β-PP的弯曲模量和弯曲强度均下降,相对分子质量越低降低幅度越大。Melt flow rate was taken as a rough measure of molecular weight of isotactic polypropylene （Ipp）. Influence of molecular weight on the crystallization behavior, thermal property, and mechanical property of β-form IPP （ β-PP） were studied using differential scanning calorimeter, X-ray diffraction, and mechanical property test. It was observed that after adding/I- nucleating agent, both the crystallization temperature and heat distortion temperature of IPP increased about 10℃, and relative content of β-form crystallization increased to 60%-70 %. The impact strength of β-PP of high molecular weight increased at least 100 % while that of low molecular weight had little improvement. The flexural modulus and flexural strength of β-PP decreased compared with neat IPP; the lower the molecular weight, the more the decrease.

关 键 词：相对分子质量 等规聚丙烯 Β晶型 成核剂 熔体流动速率 

分 类 号：TQ325.14[化学工程—合成树脂塑料工业]