基于动态共价键制备可重复加工交联聚合物

Preparation of reprocessable cross-linked polymers via dynamic covalent bonds

通过动态共价键构建聚合物交联网络,一方面高度交联的化学结构使其具有优异机械物理性能,另一方面通过链段重排可赋予其良好的自修复和重复加工性能,突破热塑性聚合物和热固性聚合物的界限,具有十分诱人的工业应用前景。从酯交换反应、二硫键交换反应、硅醇交换反应、烯烃复分解、亚胺交换反应、酰腙键交换反应等动态共价化学作用机理出发,详细介绍了基于这些动态共价键制备可重复加工交联聚合物方法和特性的研究进展,并对发展前景和面对的挑战进行了展望。

Cross-linked polymer networks with highly cross-linking chemical structures constructed via dynamic covalent bonds can provide polymers with excellent physical and mechanical properties,and also good self-healing ability and reprocessability through chain rearrangement.The technique shows great potential application in industry by breaking the boundaries between thermoplastic and thermoset polymers.In this review,based on dynamic covalent mechanisms of transesterification,disulfide exchange,siloxane silanol exchange,olefin cross-metathesis,imine exchange and acylhydrazone exchange reactions,preparation and properties of reprocessable cross-linked polymers with these dynamic covalent bonds are introduced in detail.Furthermore,existing problems and development prospects in dynamic covalent cross-linked polymers are discussed.