可逆共价型自修复PBX构筑及其损伤愈合机制研究

高聚物粘结炸药（PBX）是一类高度填充含能晶体的聚合物基复合材料，保持结构完整是PBX展现优良力学性能与安全性质的前提；然而在制造或使用过程中，PBX不可避免会产生微观损伤，受到后续的环境应力作用，作为连续相的粘结剂基体会开裂，导致PBX的结构完整性遭到破坏。使PBX中的粘结剂具备自修复能力，防止基体受损开裂，就成为含能材料领域迫切需要解决的一个科学问题。本项目针对PBX的结构特性，拟向粘结剂分子引入具有可逆共价性质的官能团，设计构建具有本征型自修复特性的PBX，使其微结构损伤在加热作用下实现自动愈合。通过开展自修复粘结剂的分子设计与结构调控研究，厘清PBX的损伤修复效果与粘结剂分子结构间的关系，从分子链的多级结构以及与炸药的界面作用等多个层面，剖析不同的力、热作用下PBX损伤的自动愈合机理。本项目的研究不仅有利于丰富含能材料的性能调控途径，而且对于PBX的延寿也具有重要的实用价值。

Polymer bonded explosive (PBX) is a sort of polymeric composites highly-filled with energetic crystals, and it is a precondition for PBX provided with excellent mechanical property and good safety to maintenance its structure integrality. PBX materials may easily suffer from damages in their manufacture and use, the microcracks will generate inside of the PBX and often take place at the interface of explosive crystal and polymeric binder, then the crack of binder network may occur, which would reduce the material mechanical properties and diminish their using life. Therefore, it is an urgent problem needing to be resolved for energetic materials that how to avoid the binder network in PBX to crack by endowing polymeric binder with self-healing property. In this project, we plan to prepare an intrinsic self-healing PBX by introducing the functional groups with reversible-bonding property (i.e. Diels-Alder (DA) bonds) into the polymer binder, which can self-heal the microdamages in PBXs through heating. The effect of the reversible-bond content of as-prepared polymeric binder on healing efficiency of PBX will be investigated, and the damage-healing mechanism of this kind of PBX will be deeply understood, which would not only be helpful for us to develop the structure-accommodating approach for energetic materials, but also be provided with practical value for prolong the life of PBXs.