writer：Fushi Li, Yunbao Gao, Nan Yan, Chunyu Zhang, Xuequan Zhang, Wei Jiang
keywords：韧性与刚性平衡, 脆韧转变, 均聚聚丙烯, 分子量分布
source：期刊
specific source：Journal of Applied Polymer Science, 2022, 139(12), e51834
Issue time：2022年

摘要：本文将数均分子量（Mn）相同但分子量分布（MWD）不同的均聚聚丙烯（HPP）与聚烯烃弹性体（POE）直接熔融共混，研究HPP的MWD对PP/POE复合材料脆韧转变（BDT）及韧性和刚性平衡的影响。结果表明，对于数均分子量相同的HPP，MWD越宽，HPP的脆性强度σb越高，复合材料的临界粒子间距（IDc）越大。较大的IDc意味着较低改性剂含量即可诱导BDT，从而降低复合材料模量损失。即MWD较宽的增韧HPP可具有更好的韧性和刚性平衡。

Abstract：In this study, homo-polypropylene (HPP) with the same number average molecular weight (Mn) while different molecular weight distribution (MWD) are directly melt blended with a polyolefin elastomer (POE) in order to study the effects of the MWD of HPP on the brittle-ductile transition (BDT) and the balance between toughness and rigidity of the PP/POE composites. The results show that for the same number average molecular weight HPP, the wider the MWD, the higher the brittle strength σb of the HPP is, and the larger the critical interparticle distance (IDc) of the composite is. Larger IDc means lower modifier content can induce the BDT, and thereby leads to less modulus loss of the composites. Namely, the toughened HPP with wider MWD can have a better balance between toughness and rigidity.

论文链接：https://doi.org/10.1002/app.51834