摘要
用端氨基硅氧烷(ATPS)、2,5-二甲基-2,5-己二醇(DMHDO)、异佛尔酮二异氰酸酯(IPDI)和端羟基聚丁二烯(HTPB)合成了基于氢键交换的本征型自愈合聚氨酯。n(IPDI)∶n(HTPB)∶n(ATPS)∶n(DMHDO)为1.8∶1∶0.8∶0的样品(P5)在室温(25℃)下自愈合效率达70%;n(IPDI)∶n(HTPB)∶n(ATPS)∶n(DMHDO)为1.8∶1∶0.6∶0.2的样品(P4)在50℃下自愈合效率达90%。硅氧烷的引入减少了空间位阻作用,利于氢键交换,使其可以在25℃下自愈合。利用分子动力学模拟探究自愈合过程中的主导氢键类型,扩链剂为受阻醇时的样品(P1),主导氢键是硬段末端氨酯键(TYPE-1)和受阻醇氨酯键(TYPE-4)所形成的氢键;两种扩链剂等比例混合的样品(P3),主导氢键有三种,分别为TYPE-1、ATPS脲键(TYPE-2)、TYPE-4氢键。扩链剂为硅氧烷的样品(P5),主导氢键是TYPE-1氢键。
Intrinsic self-healing polyurethane based on hydrogen bond exchange is synthesized with amino-terminated siloxane(ATPS),2,5-dimethyl-2,5-hexanediol(DMHDO),isophorone diisocyanate(IPDI),and hydroxyl-terminated polybutadiene(HTPB).The sample with IPDI∶HTPB∶ATPS∶DMHDO of 1.8∶1∶0.8∶0(P5)achieved a self-healing efficiency of 70%at room temperature;the sample of IPDI∶HTPB∶ATPS∶DMHDO of 1.8∶1∶0.6∶0.2(P4)self-healing efficiency of 90%at 50℃.The addition of siloxane reduces steric hindrance and facilitates hydrogen bond exchange.Molecular dynamics simulation was used to explore the dominant hydrogen bond type in the self-healing process.The dominant hydrogen bond of the chain extender is hindered alcohol(P1)which is formed by the urethane bond at the end of the hard segment and the hindered alcohol urethane bond;The chain extender is siloxane(P5)which is formed by the urethane bond at the end of the hard segment.The two chain extenders mixed in equal proportions(P3)has three types dominant hydrogen bonds,which are composed of hard segment end urethane bonds,hindered alcohol urethane bonds and ATPS urea bonds.
作者
谢高长
李佳萱
陈嘉梁
余旺旺
罗艳龙
XIE Gaochang;LI Jiaxuan;CHEN Jialiang;YU Wangwang;LUO Yanlong(Nanjing Vocational University of Industry Technology,Nanjing 210023,China;College of Science,Nanjing Forestry University,Nanjing 210037,China;School of Mechanical Engineering,Nanjing Vocational University of Industry Technology,Nanjing 210023,China)
出处
《弹性体》
CAS
2024年第2期37-43,共7页
China Elastomerics
基金
国家自然科学基金项目(51903122)
江苏省高校自然基金重大项目(22KJA430012)
江苏省大学生身体素养发展特征及提升策略研究项目(2023SJYB0548)。
关键词
聚氨酯
自愈合
氢键
分子动力学模拟
polyurethane
self-healing
hydrogen bonding
molecular dynamics simulation
