文献类型：期刊文献

英文题名：Good extrusion foaming performance of long-chain branched PET induced by its enhanced crystallization property

作者：Yao, Shun[1];Guo, Tianhao[1];Liu, Tao[1];Xi, Zhenhao[1];Xu, Zhimei[1];Zhao, Ling[1,2]

机构：[1]East China Univ Sci & Technol, Shanghai Key Lab Multiphase Mat Chem Engn, Shanghai 200237, Peoples R China;[2]Xinjiang Univ, Coll Chem & Chem Engn, Urumqi, Peoples R China

年份：2020

卷号：137

期号：41

外文期刊名：JOURNAL OF APPLIED POLYMER SCIENCE

收录：;EI(收录号：20201308365030);WOS:【SCI-EXPANDED(收录号:WOS:000521850500001)】；

基金：Fundamental Research Funds for the Central Universities, Grant/Award Number: 22221714005; National Key Research and Development Program of China, Grant/Award Number: 2016YFB0302200

语种：英文

外文关键词：crystallization; foams; poly(ethylene terephthalate); rheology

摘要：Poly(ethylene terephthalate) (PET) was modified by regulating different contents of branching agent epoxy-based multifunctional oligomer and chain extender pyromellitic dianhydride in reactive extrusion process. The modified PET with better long-chain branched (LCB) structure boosted its rheological properties, and its enhancement of melt viscoelasticity resulted in excellent foamability in molten-state foaming process using supercritical CO2 as blowing agent. More importantly, the branched structures acted as crystal sites to accelerate the crystallization kinetic of LCB PET whether under atmospheric pressure or high-pressure CO2. The shear and elongation flow inside die further quickly induced the crystallization of LCB PET. The rapidly generated fine crystals could both introduce heterogeneous cell nucleation and suppress CO2 escape, so the cell morphology of LCB PET in continuous extrusion foaming process exhibited a three-fold increase in cell density and smaller uniform cell size with respect to those of other foam-grade PET with long-chain structure.