文献类型：期刊文献

英文题名：A Novel Strategy for Achieving High Melt Strength Polypropylene and an Investigation of Its Foamability

作者：Zhou, Shuai[1];Zhao, Shicheng[1];Xin, Zhong[1];Wang, Weixia[1]

机构：[1]E China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai 200237, Peoples R China

年份：2014

卷号：53

期号：10

起止页码：1695

外文期刊名：JOURNAL OF MACROMOLECULAR SCIENCE PART B-PHYSICS

收录：;EI(收录号：20145200357432);WOS:【SCI-EXPANDED(收录号:WOS:000345498300009)】；

基金：The authors thank the National Natural Science Funds of China (grant nos. 21106042 and u1162110), and the Fundamental Research Funds for the Central Universities of China for financial support.

语种：英文

外文关键词：foam; high melt strength; polypropylene; reactive extrusion; rheology; vinyl polydimethylsiloxane

摘要：A novel and feasible strategy for preparing high melt strength polypropylene (HMSPP) was developed by a melt grafting reaction in the presence of macro-monomer vinyl polydimethylsiloxane (VS), co-monomer styrene (St), and initiator benzoyl peroxide through a one-step reactive extrusion. The rheological behaviors, melt strength, and foaming ability of HMSPP were studied. The results showed that VS and St were successfully grafted onto polypropylene (PP), and the weight average molecular weight, molecular weight distribution, and melt strength ofHMSPP were dramatically increased compared with those of the virgin isotactic polypropylene (iPP). Especially, the melt strength of HMSPP increased from 0.022 N for the virgin iPP to 0.29 N, which made the foamability of HMSPP significantly improved when supercritical carbon dioxide was used as the blowing agent. The foaming condition was optimized to 160 degrees C and 14 MPa, for which HMSPP foams with a high expansion ratio of 66 times and a high cell density of about 5.8 x 10(7) cell/cm(3) were obtained, while the virgin iPP did not yield foams with good cell structure. Moreover, the resultant HMSPP could be foamed in a remarkably wide temperature range from 145 degrees C to 165 degrees C, which would be of great significance for industrial application.