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自修复材料由于其延长材料使用寿命,节约成本和能源,具有可持续发展等优点,引起了广泛的关注.其中基于可逆共价键的自修复材料因其可以多次重复修复,且键能高于可逆非共价键,更适合于制备高强度的自修复材料.但良好的自修复效果和优异的机械性能往往不能共存,因为动态可逆共价键相较于传统的共价键键能较低,更容易受到破坏,而且良好的自修复效果要求分子链能够快速运动,在损伤表面进行重组.所以,目前对于基于动态共价交联键的聚合物,保持良好的自修复效果的同时提高其力学性能是当前研究的难题所在.为了提高自修复材料的力学性能,将分子尺度的乙烯基多面体低聚倍半硅氧烷(OVPOSS)通过巯基-烯反应引入交联网络.通过测试表明,OVPOSS质量分数达到10%时,复合材料的机械性能最好,断裂伸长率也有所增加;并且依然具有95%以上的恢复率,达到了在不影响其修复效果的情况下增加力学性能的目的.“,”Self-repairing materials have attracted extensive attention due to the advantages such as extending the service life of materials,saving cost and energy and promoting sustainable development.Of which,self-repairing materials based on reversible covalent bonds are more suitable for preparing high-strength self-repairing materials since it can repair repeatedly many times and the bond energy of its reversible covalent bond is higher than reversible non-covalent bond.However,good self-repairing effects can hardly coexist with excellent mechanical properties for a same material because the dynamically reversible covalent bond owns lower bond energy than traditional covalent bonds and is therefore easier to be damaged.Furthermore,good self-repairing effects require molecular chain to move fast in order to recombine on damaged surfaces.The difficult issue for current research is to make the dynamically covalently crosslinked bond-based polymer retain good self-repairing effect and enhance mechanical property.In order to improve the mechanical properties of self-repairing materials,molecular-scale polyhedral oligomeric silsesquioxanes (POSS) are drawn into the crosslinking network through the thiol-ene reaction.Tests show that the mechanical properties of the composite will be the best and its elongation at break can also be increased when the mass content of OVPOSS reaches 10%.Meanwhile the composite material can achieve a repair efficiency of more than 95%,achieving the purpose of improving the mechanical performance without affecting the repair efficiency.