化工学报2019，Vol.70Issue(10)：4043-4051,9.DOI:10.11949/0438-1157.20190477
软段结构对聚氨酯弹性体性能的影响
Effect of soft segment structure on properties of polyurethane elastomers
张聪聪 1郑梦凯 1李伯耿1
作者信息
- 1. 化学工程联合国家重点实验室,浙江大学化学工程与生物工程学院,浙江杭州310027
- 折叠
摘要
Abstract
Using four different soft segments, i. e. polyterahydrofuran diol (PTMG), polycaprolactone diol (PCL), hydroxyl-terminated polybutadiene with high cis-1, 4 content (HTPB), and commercial hydroxyl-terminated polybutadiene produced by free radical polymerization (FHTPB), four kinds of polyurethane elastomers (PUE) were prepared by a two-step solution polymerization. The effects of soft segment structure on mechanical properties and thermal properties at room temperature and low temperature were investigated by tensile test, dynamic mechanical property analysis (DMA), differential scanning calorimetry (DSC) and thermogravimetric analysis. It has been found that the tensile strength and elongation at break of the four PUEs at low temperature (-30℃) are superior to those at room temperature. This is not only related to the autofrettage effect induced by crystallization of soft segment at low temperature, but also to the increase of the degree of micro-phase separation between the soft and hard segments. Compared with the other three kinds of PUE, the soft segment in HTPB-PUE has lowest polarity and glass transition temperature (Tg), so the micro-phase separation is in highest degree, and the elastomer has the most excellent flexibility. Even at -30℃, elongation at break of the HTPB-PUE is up to 660%. PCL-PUE and PTMG-PUE are rigid because their soft segments are easy to crystallize and their degree of micro-phase separation between soft and hard segment is low. The cyclic tensile testing indicated that HTPB-PUE and FHTPB-PUE still have excellent elasticity at-30℃. The results from DSC and DMA showed that the Tg of HTPB-PUE is much lower than the other three PUEs, and the value from DSC is about -103℃. The initial thermal decomposition temperatures of the four PUEs are very similar, and are all around 270℃.关键词
聚氨酯/弹性体/软段/结构/性能Key words
polyurethane/elastomer/soft segment/structure/properties分类
化学化工引用本文复制引用
张聪聪,郑梦凯,李伯耿..软段结构对聚氨酯弹性体性能的影响[J].化工学报,2019,70(10):4043-4051,9.
