基体分子量对PP/EPR共混物力学性能的影响  

Effect of Matrix Molecular Weight on Mechanical Properties of PP/EPR Blends

作　　者：鞠翼龙 刘宣伯[2] 乔泽爽 白红伟[1] 傅强[1] JU Yi-long;LIU Xuan-bo;QIAO Ze-shuang;BAI Hong-wei;FU Qiang(College of Polymer Science and Engineering,State Key Laboratory of Polymer Materials Engineering,Sichuan University,Chengdu 610065,China;Institute of Material Science,SINOPEC Beijing Research Institute of Chemical Industry,Beijing 100013,China)

机构地区：[1]四川大学高分子科学与工程学院,高分子材料工程国家重点实验室,四川成都610065 [2]中国石化北京化工研究院材料科学研究所,北京100013

出　　处：《塑料科技》2022年第2期10-13,共4页Plastics Science and Technology

基　　金：中国石油化工股份有限公司科技部项目(219004-1)。

摘　　要：以二元乙丙橡胶(EPR)增韧的聚丙烯(PP)共混物为研究对象,探究PP基体分子量对PP/EPR共混物力学性能的影响。结果表明:随着基体分子量的增加,PP/EPR共混物的冲击韧性、拉伸强度和弹性模量均明显提高,且发生脆韧转变所需的临界EPR含量和脆韧转变温度均显著降低。当基体数均分子量(Mn)由3.8×10^(4) g/mol增至8.8×10^(4) g/mol,临界EPR含量从28%减至10%,脆韧转变温度从-17℃降至-30℃。分子量对基体结晶度和结晶形貌没有明显影响,但共混物的力学性能随分子量的变化不是单纯线性关系。当基体数均分子量为(5~7)×10^(4) g/mol的范围内,共混物的临界EPR含量和缺口冲击强度呈现跳跃性转变,该转变可能与EPR分散相尺寸减小有关,EPR粒子的尺寸越小,增韧效果越好。Taking ethylene propylene rubber(EPR)toughened polypropylene(PP)blends as research object,the effect of PP matrix molecular weight on the mechanical properties of PP/EPR blends was investigated.The results show that with the increasing of matrix molecular weight,the impact toughness,tensile strength and elastic modulus of the PP/EPR blends are significantly improved,and the critical EPR content and the brittle-ductile transition temperature required for the brittle ductile transition are significantly reduced.When the matrix number average molecular weight(Mn)is increased from 3.8×10^(4) g/mol to 8.8×10^(4) g/mol,the critical EPR content is decreased from 28%to 10%,and the brittle ductile transition temperature is decreased from-17℃to-30℃.The molecular weight has no obvious effect on the crystallinity and crystalline morphology of the matrix,but the mechanical properties of the blends is not simple linear relationship with molecular weight.When number average molecular weight of matrix is in the range of(5~7)×10^(4) g/mol,the critical EPR content and the notched impact strength of the blends show a jumping transition,which may be related to the reduction of the size of the EPR dispersed phase.The smaller the size,the better the toughening effect.

关 键 词：聚丙烯 二元乙丙橡胶 分子量 刚韧平衡 

分 类 号：TQ325.14[化学工程—合成树脂塑料工业]