近年来,人们发现具有共价适应性网络(CAN,或动态共价网络)的环氧树脂及其复合材料可以兼具传统热固性塑料优异的机械性能、热性能和热塑性塑料的可再加工属性,这些特性使得回收再利用热固性材料变成了可能。首先概述了当前基于CAN合成可回收热固性塑料的策略,分别介绍了酯交换、狄尔斯-阿尔德反应、亚胺键、二硫键复分解和多个共价键共同作用。介绍了可回收热固性材料和热固性复合材料在工业中的新兴应用,包括粘合剂、可穿戴设备、涂料和3D打印材料等。最后,简要总结了现有遇到的挑战和对未来前景的看法。
In recent years,it has been discovered that epoxy resins and their composites with covalent adaptive networks (CAN,or dynamic covalent networks) can combine the excellent mechanical and thermal properties of traditional thermosets with the reworkable properties of thermoplastics.These properties make it possible to recycle thermoset materials.The current strategies for the synthesis of recyclable thermosetting plastics based on CAN were firstly summarized,and introduced respectively the transesterification,Diels-Alder reaction,imine bond,disulfide bond metathesis,and multiple covalent bonds.Emerging applications of recyclable thermosets and thermoset composites in industry were presented,including adhesives,wearable devices,coatings,and 3D printing materials.Finally,brief summary of existing challenges and perspectives on future prospects was given.
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