文献类型：期刊文献

英文题名：Effects of crystal structure on the foaming of isotactic polypropylene using supercritical carbon dioxide as a foaming agent

作者：Jiang, Xiu-Lei[1];Liu, Tao[1];Xu, Zhi-Mei[1];Zhao, Ling[1];Hu, Guo-Hua[2,3];Yuan, Wei-Kang[1]

机构：[1]E China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[2]Nancy Univ, Lab Chem Engn Sci, CNRS, ENSIC,INPL, F-54001 Nancy, France;[3]Inst Univ France, F-75005 Paris, France

年份：2009

卷号：48

期号：2

起止页码：167

外文期刊名：JOURNAL OF SUPERCRITICAL FLUIDS

收录：;EI(收录号：20091512028360);WOS:【SCI-EXPANDED(收录号:WOS:000264250800010)】；

基金：The authors are grateful to the National Science Foundation of China and PetroChina for the support of a joint project on multi-scale methodologies (20490204), the National Science Foundation of China (50703011), Program for Changjiang Scholars and Innovative Research Team in University (IRT0721) and the 111 Project (1308021).

语种：英文

外文关键词：Supercritical carbon dioxide; Foaming; Polypropylene; Crystal structure; Cell structure; Semi-crystalline polymer

摘要：This paper aims to study, for the first time, the effect of crystal structure on the cell formation in an isotactic polypropylene (iPP) during a solid-state foaming process using supercritical carbon dioxide (scCO(2)) as a foaming agent. Results show that the spherulite structure exerted a significant impact on the cell morphology of foamed iPP. Very interestingly, under a relatively low pressure, microcells could appear at the centers of spherulites of iPP where the melting started proceeding first. They also appeared in the amorphous domains located in between spherulites and the interlamellar regions of spherulites of iPP. The larger the size of an amorphous area, the lower the CO2 saturation pressure needed to induce cell formation. When microcells were generated in the interlamellar regions, tie fibrils bridging lamellae could be stretched. gamma-Crystals were formed at very high CO2 saturation pressure. (C) 2008 Elsevier B.V. All rights reserved.