Creep-Resistant Covalent Adaptable Networks with Excellent SelfHealing and Reprocessing Performance via Phase-Locked Dynamic Covalent Benzopyrazole-Urea Bonds  

作　　者：Miao Xie Xiao-Rong Wang Zhan-Hua Wang He-Sheng Xia 

机构地区：[1]State Key Laboratory of Polymer Materials Engineering,Polymer Research Institute,Sichuan University,Chengdu,610065,China [2]School of Petrochemical Engineering,Liaoning Petrochemical University,Fushun,113001,China

出　　处：《Chinese Journal of Polymer Science》2024年第10期1545-1556,I0013,共13页高分子科学（英文版）

基　　金：supported by the National Natural Science Foundation of China(No.52173113)。

摘　　要：Covalent adaptive networks(CANs)are capable of undergoing segment rearrangement after being heated,which endows the materials with excellent self-healing and reprocessing performance,providing an efficient solution to the environment pollution caused by the plastic wastes.The main challenge remains in developing CANs with both excellent reprocessing performance and creep-resistance property.In this study,a series of CANs containing dynamic covalent benzopyrazole-urea bonds were developed based on the addition reaction between benzopyrazole and isocyanate groups.DFT calculation confirmed that relatively low dissociation energy is obtained through undergoing a five-member ring transition state,confirming excellent dynamic property of the benzopyrazole-urea bonds.As verified by the FTIR results,this nice dynamic property can be well maintained after incorporating the benzopyrazole-urea bonds into polymer networks.Excellent self-healing and reprocessing performance is observed by the 3-ABP/PDMS elastomers owing to the dynamic benzopyrazole-urea bonds.Phase separation induced by the aggregation of the hard segments locked the benzopyrazole-urea bonds,which also makes the elastomers display excellent creep-resistance performance.This hard phase locking strategy provides an efficient approach to design CANs materials with both excellent reprocessing and creep-resistance performance.

关 键 词：Covalent adaptive networks Self-healing polymer Dynamic covalent bond 

分 类 号：TQ317[化学工程—高聚物工业]