防渗油PBX炸药中石蜡微胶囊与粘结剂界面作用机制的研究

It's an insurmountable problem in explosives system that the paraffin wax is greatly insensitive on one hand, while highly unstable because of the uneven distribution, oil-leaking (under high temperature) and crystal separation on the other hand. This problem largely hinders the further development of insensitive high explosives. The main goal of this project is to synthesize and structurally characterize a series of new paraffin microcapsule. By doing some surface modifications on the surface of the microcapsule, it can be used to replace part of the paraffin wax in PBX explosive system. The strong interaction effect between the microcapsule and the adhesive will replace the weak interaction effect between the paraffin wax and the adhesive. Since the amount of exposed paraffin wax in the system will considerably decrease, the paraffin leakage is prevented. The new explosive system will maintain the insensitivity of the old system while largely improve its mechanical properties. In this project, we will analyze the connection between the synthesis conditions and the wall structure, property, amount of the core materials of the microcapsules. We will also study the influence of the shape, size, thickness of the walls, elasticity, polarity and surface morphology of the microcapsule on the mechanical property and insensitivity of the explosive system. We will state the microstructure and interaction mechanism between the microcapsule wall and the interface of the adhesive. It's worth noticing that up till now, there is no research concerning the application of paraffin microcapsules on explosives. The implementation of this project will provide a new approach and theoretical foundation to the design of new microcapsules and the synthesis of the high-performance PBX explosives.

石蜡的高效钝感和由于石蜡的非极性造成的分布不均匀、高温渗油及结晶析出而影响体系稳定性之间的矛盾，长期以来一直是火炸药领域无法克服的难题，极大地阻碍了钝感炸药的发展。本项目致力于合成及结构表征一系列新型的石蜡微胶囊并对其表面进行改性处理，代替PBX炸药体系中的部分石蜡，通过微胶囊与粘结剂间较强的相互作用代替石蜡与粘结剂间弱的相互作用，减少裸露石蜡用量从而避免石蜡流淌，在保持钝感效果的同时改善体系的力学性能，构建新型的PBX炸药体系。深入考察合成条件与微胶囊的壁材结构、性质及芯材含量之间的关系。探索在胶料聚合、固化和撞击过程中，微胶囊颗粒的形状、大小、囊壁厚度、弹性、极性、表面形态对体系力学性能和钝感效果的影响规律，阐明囊壁与粘结剂界面层的微观结构和相互作用机制。截至目前，尚未见石蜡微胶囊在炸药中应用的相关报道。本项目的实施，有望为新型微胶囊的设计和高性能PBX炸药的制备提供新思路和理论依据。

本课题组通过四年的探索和研究，按照计划全面完成了本项基金课题的任务，并取得了突破性进展。石蜡的高效钝感和由于石蜡非极性造成的分布不均匀、高温渗油及结晶析出而影响体系稳定性之间的矛盾，长期以来一直是火炸药领域无法克服的难题，极大地阻碍了钝感炸药的发展。对此，本项目进行了如下3方面的工作：1）以熔点在50 ℃以上的普通固体石蜡为芯材，合成并结构表征了四种壁材的新型石蜡微胶囊，且对其表面进行改性处理。深入探究合成条件与微胶囊的粒径、壁材结构、性质及芯材含量之间的关系，合成综合性能优异的微胶囊。2）采用PBX炸药所用胶料配方，以微胶囊替代部分石蜡制备HTPB粘结剂，研究发现微胶囊在HTPB基体中分布均匀，并能有效减少石蜡在胶料断面的脱粘现象，同时提高胶料的热稳定性和力学性能。3）采用石蜡微胶囊代替部分石蜡，使PBX炸药的渗油率降低了3/4，同时提升了药柱的力学性能，并保持原有的钝感效果不变，属于PBX炸药的钝感防渗油研究方面的突破性进展，目前国内外尚未见有此类报道。这一研究结果，对于研制新型防渗油深钝感PBX炸药具有重要意义。.相关工作已申请国家发明专利5项，发表SCI收录论文15篇，EI收录论文9篇。培养硕士研究生9名，博士研究生5名。