文献类型：期刊文献

英文题名：Internal structure and crystallinity investigation of segmented thermoplastic polyurethane elastomer degradation in supercritical methanol

作者：Liu, Lu[1];Wu, Yongqiang[1];Zhu, Zibin[1]

机构：[1]East China Univ Sci & Technol, Res Inst Chem Technol, Dept Chem Engn, 130,Meilong Rd, Shanghai 200237, Peoples R China

年份：2017

卷号：140

起止页码：17

外文期刊名：POLYMER DEGRADATION AND STABILITY

收录：;EI(收录号：20171603574421);WOS:【SCI-EXPANDED(收录号:WOS:000405880000003)】；

语种：英文

外文关键词：Internal structure; Crystallinity; Degradation behaviour; Segmented polyurethane; Supercritical methanol

摘要：This work is the first to investigate the internal structure and crystallinity variance of segmented thermoplastic polyurethane elastomer (TPU) degradation in supercritical methanol. Molecular weight distribution (MWD) and molecular structure were determined using GPC, FT-IR and NMR. DSC and XRD were employed to explore the thermal behaviour and morphologic change of TPU, respectively. Results indicated that the segmented TPU has unique degradation behavior because of the three kinds of morphology of hard segments. The short range hard segments dissolved in soft blocks were amorphous. The long range hard segments mixed with and separated from soft blocks formed crystallites. These crystallites ruptured from the soft blocks in initial time period and the soft blocks dissolved in methanol, as indicated by the disappearance of the undecomposed TPU peak in MWDs. The remaining residues were hard segments crystallites which had narrow sharp MWDs. The following process was in two phases. In solid phase, hard segments crystalline structures were destroyed gradually, the melting points decreased correspondingly; in liquid phase, soft segments broken from short range hard segments and fractured. (C) 2017 Published by Elsevier Ltd.