蓖麻油作交联剂的聚氨酯弹性体的合成及性能

摘要

At first,the prepolymer were prepared from PTMG and HDI with different molar ratio, then PU were synthesized respectively with BD, CO and the mixture of BD and CO as crosslinker. The hydrogen bonding degree, morphology, mechanical properties and thermal properties of the PU with various hard segment content and CO content were studied by FTIR,AFM, tensile test and TGA. The results show that the type and dosage of the isocyanate and crosslinker have a great influence on the performance of the PU. As the content of the diisocyanate increases, the mechanical properties and thermal stability properties of the PU increases. As the quantity of CO increases, the hydrogen bonding degree of the PU decreases, the micro phase separation degree of the soft and hard segment decreases, and the mechanical performance decreases ,but the thermal stability were improved when the crosslinking and branched degree of segment were improved due to the increase of the content of the CO.%以不同摩尔比的四氢呋喃均聚醚（PTMG）和1，6-亚己基二异氰酸酯（HDI）合成聚氨酯（PU）预聚体，再分别用丁二醇（BD）、蓖麻油（CO）以及BD和CO混合物进行扩链交联，合成了一系列不同CO含量的PU.通过FTIR、AFM、拉伸实验和TGA，对不同硬段含量和CO含量PU的氢键化程度、相形态结构、力学性能和热性能进行了比较。结果表明，二异氰酸酯和扩链剂的种类及用量对PU的性能均有很大的影响。随着PU中二异氰酸酯用量的增加，其力学性能和热稳定性能提高。随着扩链剂中CO用量的增加，PU氨酯键的氢键化程度降低，其软、硬段的微相分离程度降低，导致其力学性能降低。但CO用量的增加会提高PU分子链的交联和支化，因而其热稳定性能得到提高。