Self-healed microcracks in polymer bonded explosives via thermoreversible covalent bond and hydrogen actions  

作　　者：Yu-bin Li Xu Zhao Ya-jun Luo Zhi-jian Yang Li-ping Pan Cheng-cheng Zeng Cong-mei Lin Xue Zheng 

机构地区：[1]Institute of Chemical Materials,China Academy of Engineering Physics,Mianyang,621900,China

出　　处：《Defence Technology（防务技术）》2023年第10期183-194,共12页Defence Technology

基　　金：the National Natural Science Foundation of China(Grant No.21875229);NSAF(Grant No.U2030202)for grants in support of this wok。

摘　　要：Polymeric materials used for the polymer bonded explosive(PBX)or other energetic composite materials(ECMs)that simultaneously possess excellent mechanical properties and high self-healing ability,convenient healing,and facile fabrication are always a huge challenge.Herein,self-healing linear polyurethane elastomers(PTMEG2000-IPDI-DAPU,denoted as 2I-DAPU)with high healing efficiency and mechanical properties were facilely fabricated by constructing reversible covalent bonds and dynamic hard domains into polymer chains.Furthermore,a TATB-based PBX using as-prepared 2I-DAPU polymer as the binder was constructed,disclosing an excellent self-healing property to heal cracks generated during fabrication,transportation and storage.The damage healing manner of such a PBX sample was investigated by means of prefabricated damage through mechanical load,heal treatment via heating at high temperature,and CT-scanning the inner structure and mechanical property characterization via Brazilian test.The self-healing mechanism of internal damage in PBX was preliminarily explored.We propose that this 2I-DAPU binder with Diels-Alder bonds could generate plentiful active surface groups resulting from damage and drive self-healing at fitting temperature and increase the slightly packed hard phase via incorporating a small amount of hydrogen bonds.This work may offer a novel strategy for improving mechanical property and healing ability in the field of self-healing material which could help expand its applications with enhanced versatility in mechanical-enhanced functional materials.

关 键 词：Polymer bonded explosives Self-healing polymers Diels-alder(DA)bonds H-BOND 

分 类 号：TQ560.1[化学工程—炸药化工]