摘要
为解决自修复弹性体同时具有优异的力学性能和自修复性能的矛盾,首先将原料胱氨酸(CYS)进行甲酯化得到含双硫键的二胺扩链剂胱氨酸二甲酯(CDE),然后以聚四氢呋喃醚二醇(PTMG)为软段,异佛尔酮二异氰酸酯(IPDI)和CDE为硬段,固定摩尔比为1∶3∶2,采用两步法制备了自修复聚氨酯脲(SH-PUU)弹性体,并对SH-PUU进行了红外光谱测试、拉曼光谱测试、力学性能测试、自修复性能测试、划痕修复微观形貌观察、应力松弛和动态力学性能测试。实验结果表明:SH-PUU的软段和硬段的玻璃化转变温度分别为−38.5℃和77.6℃,微相分离程度较高,SH-PUU具有良好的力学性能,拉伸强度为13.6MPa,断裂伸长率达531.3%;同时SH-PUU具有高效的自修复能力,试样在经过80℃修复2h后,基于拉伸强度的自修复效率达到97.1%,SH-PUU的力学性能和自修复性能达到较好的平衡。SH-PUU的高自修复能力是由动态双硫键和氢键协效增强引起的,其通过加热方式的自修复机理为:SH-PUU中的动态双硫键在80℃发生可逆交换反应,SH-PUU中的氢键在低于100℃时会重新形成。
In order to solve the contradiction between excellent mechanical properties and self-healing properties of self-healing elastomers,a diamine chain extender cystine dimethyl ester(CDE)containing disulfide bond was obtained by methyl esterification of cysteine(CYS).The self-healing poly(urethane urea)(SH-PUU)elastomer was prepared through two-step approach by using polytetramethylene ether glycol(PTMG)as the soft segments and isophorone diisocyanate(IPDI)and CDE as the hard segments,with the molar ratio of 1︰3︰2.The SH-PUU was characterized by infrared spectrum,Raman spectrum,mechanical property test,self-healing property test,micromorphology observation of scratch healing,stress relaxation and dynamic mechanical property analysis.The results showed that the glass transition temperature of soft segments and hard segments was−38.5℃and 77.6℃,respectively,indicating that SH-PUU had a high degree of microphase separation.SH-PUU had outstanding mechanical properties,which tensile strength and elongation at break was 13.6MPa and 531.3%,respectively.The self-healing efficiency of 97.1%after healing at 80℃for 2h based on tensile strength indicated the performance of SH-PUU got a good balance between mechanical properties and self-healing properties.The high self-healing ability of SH-PUU was caused by the enhancement of the synergistic effect of dynamic disulfide bonds and hydrogen bonds.The self-healing mechanism of SH-PUU is that the dynamic disulfide bonds in SH-PUU occur exchange reaction reversibly at 80℃,and the hydrogen bonds in SH-PUU regenerate at less than 100℃.
作者
王玉龙
胡国胜
张静婷
白静静
吕秦牛
李振中
WANG Yulong;HU Guosheng;ZHANG Jingting;BAI Jingjing;LYU Qinniu;LI Zhenzhong(Institute of Macromolecules and Bioengineering,North University of China,Taiyuan 030051,Shanxi,China;Department of Materials Engineering,Taiyuan Institute of Technology,Taiyuan 030051,Shanxi,China)
出处
《化工进展》
EI
CAS
CSCD
北大核心
2021年第1期324-331,共8页
Chemical Industry and Engineering Progress
基金
西安近代化学研究所开放合作创新基金(204-J-2019-0387-1/6-18)
山西省“1331工程”重点学科建设项目(2017-6-02-17)。
关键词
双硫键
氢键
聚氨酯脲
自修复
胱氨酸二甲酯
disulfide bonds
hydrogen bonds
poly(urethane urea)
self-healing
cystine dimethyl ester
