传统的热固性树脂因不可逆的交联网络结构而不溶、不熔,导致其难以降解回收,造成环境污染及资源浪费。通过分子设计,将可裂解键或动态共价键引入到热固性树脂的交联网络,在一定的降解条件可实现传统热固性树脂的可控降解是解决上述问题的有效途径之一。介绍了传统热固性树脂回收利用面临的问题,综述了不同类型可降解热固性树脂的降解机理、制备方法及可回收性,最后指出目前可降解热固性树脂存在的问题,并对未来重点的研究方向进行展望。
Conventional thermosetting resins are infusible and insoluble due to their irreversible cross-linking network structure,which makes them difficult to degrade,recycle and reuse,causing environmental pollution and waste of resources.One effective strategy to solve the above issues is that the cleavable bonds or dynamic covalent bonds are incorporated into the crosslinking network of thermosetting resins by molecular design,and the controllable degradation of traditional thermosetting resins can be achieved under certain degradation conditions.In this review,the problems faced by the recycling of conventional thermosetting resins were introduced.The degradation mechanisms,preparation methods and recyclability of different types of degradable thermosetting resins were reviewed.Finally,the current challenges in degradable thermosetting resins were pointed out,and the future research directions were envisioned.
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