为探究本征型自修复聚氨酯材料结构与性能的关系,平衡其自修复效率与强度之间的矛盾,采用六亚乙基二异氰酸酯(HDI)三聚体作交联剂,4,4-二氨基二苯二硫醚(AFD)作扩链剂,将可逆双硫键引入聚酯型聚氨酯弹性体中。研究发现:制备的自修复聚氨酯弹性体拉伸强度可达7.7MPa,在60℃,修复时间为24h的条件下,基于拉伸强度的自修复效率高达97.4%;而普通不含有双硫键(只含氢键作用)的弹性体拉伸强度为9.3MPa,在同等条件下的自修复效率为58.0%,表明双硫键的存在使得弹性体自修复效率在原来的基础上提高了67.9%。制备的弹性体具有多次自修复能力,其二次自修复效率为62.3%。
In order to investigate the structure and property relationships of intrinsic self-healing poly-urethane and balance the seemly contradictory forces between its self-healing efficiency and mechanical strength, the reversible disulfide bonds were introduced into polyester-polyurethane by taking hexam- ethylene diisocyanate (HDI) trimers as the cross-linker and 4,4-diamino diphenyl disulfide as the chain-extender. The results show that the optimal self-healing elastomer exhibits a tensile strength of 7. 7MPa and a maximum self-healing efficiency of 97. 4% at 60°Cafter 24 hours, whereas the common elastomer synthesized without disulfide bonds (via H-bonding interactions) only exhibits a tensile strength of 9. 3MPa and a maximum self-healing efficiency of 58. 0% under the same condition, indica-ting that the existence of disulfide bonds helps to increase the self-healing efficiency by 67. 9%. The prepared elastomer is found to have multi time self-healing capabilities and the second time self-healing efficiency is 62. 3%.