嵌入小分子物质的主客体炸药设计、制备及性能研究

The synthesis of higher density, greater energy containing and more stable high power explosives is one of the most exciting areas in energetic material research. In this project, host-guest chemistry is introduced into the design of novel energetic materials. A novel explosive crystal with high explosive as host and small molecules as guests is constructed via molecule engineering. Theoretical calculation methods such as DFT are used to investigate the interactions between host and guest molecules, evaluate the structural stability and explosive performance of the designed explosive crystals. Molecular dynamic simulation is applied to demonstrate the incorporation of CL-20（HMX）and guest molecules in different conditions，thus proper synthsis condition and synthesis route can be predicted theoretically. Based on the results of theoretical calculation and molecular dynamic simulation, two synthesis routs will be adopted for the synthesis of a series of host-guest explosives: (1) high pressure synthesis, in which the reaction between the gust molecules and the CL-20 (HMX) crystals in a most stalbe form or pre-transferred to a larger cavity form will process under high presure around 10MPa; (2) in-stiu crystallization, in which the guest molecules will be introduced during the recrystallization of CL-20 (HMX). The crystal structures of the resulting products will be determined and the stability, safety and energy density will be measured. Combined with the theoretical calculatiion results, the relationship between the content and the structure of the corresponding components and the resulting explosive properties，the interaction between host and guest molecules and the formation mechanism of host-guest explosives will be illuminated. This research may further enhance the energy density of present high energy explosives, change the explosion mechanism and effect, explore a novel route for the property improvement of high power explosives and provide a theoretical foundation and practical direction for the design and synthesis of novel high explosives.

设计和制备综合性能优良的高能炸药是目前含能材料研究的热点方向之一。将主客体化学思想引入炸药晶体设计，构建以CL-20（HMX）炸药为主体，嵌入小分子物质为客体的填隙式主客体炸药晶体，采用DFT计算主客体分子间相互作用，预估其结构和性能。运用MD模拟探索客体分子进入炸药晶体的条件和方式。基于MD模拟结果，拟采用两种方法进行主客体炸药制备（1）高压法:小分子物质在10MPa左右与炸药晶体反应，炸药晶体为最稳定晶型或预先转化成晶胞空腔更大的晶型；（2）原位结晶法:溶解重结晶过程通入小分子物质。测定其晶体结构、稳定性、安全性和能量等，结合理论计算成果，揭示主客体炸药组成、结构与稳定性、安全性和能量的构效关系，阐明主客体分子相互作用机理及主客体炸药形成机理。该研究可望提高炸药能量密度、或改变爆炸反应机理和效应，开辟通过嵌入小分子物质进行炸药性能调控的新途径，为新型高能炸药设计提供理论指导和技术支撑。

现代武器对含能材料提出了“精确打击、高效毁伤、高生存能力”等更高要求，致使传统含能材料面临严峻挑战。针对高能炸药常规设计思路难以在近期内大幅度提高炸药性能的难题，本项目将主客体化学思想引入炸药晶体设计，构建了以高能炸药CL-20为主体，在晶胞空腔内嵌入活性小分子物质为客体的新型填隙式主客体炸药晶体。. 首先，采用理论计算方法对主客体炸药进行设计，筛选了合适的客体分子，并探索了客体分子进入炸药晶体的条件和方式。其次，创造性的开发了基于气-液共组装技术、气-固置换反应技术、低温重结晶技术、超临界流体技术及金刚石对顶砧高压负载技术的主客体炸药构筑方法。成功将多种客体分子，例如N2O、CO2、O2、H2O2、NH2OH、CH3OH等分子嵌入到高能炸药CL-20的晶胞空腔中，制备获得了至少5种的新型主客体炸药晶体，其中CL-20/N2O主客体炸药的综合性能与ε-CL-20相比，得到了显著提升。并通过优化实验条件，获得了温和实验条件下主客体炸药的放大制备方法，目前已能实现单次百克量级的CL-20基主客体炸药晶体的制备。最后，利用单晶衍射仪解析获得了新型主客体炸药的晶体结构，表征获得了主客体炸药的粉末XRD、FTIR、拉曼、固体核磁、DSC-TG、TG-FTIR、原位XRD等理化性能，测试获得了主客体炸药摩擦感度、撞击感度、静电火花感度、冲击波感度等安全性能，试验获得了部分主客体炸药的燃速、爆热和爆压等数据。而且结合理论计算模拟结果，揭示了客体组分、占位率、晶体结构等参数与稳定性、安全性和爆轰能量的构效关系。利用理论计算方法，阐明了主客体分子之间的相互作用机理，并且分别提出了基于气-液反应和气-固反应的主客体炸药形成机制。. 通过本项目的研究全面完成了预期的研究内容，达到了预定目标，满足结题要求。该研究可望提升炸药晶体密度、改善氧平衡、增加释气量，并改变爆炸反应机理和效应，开辟通过晶胞内嵌活性物质进行炸药性能调控的新途径，为新型含能材料设计提供理论指导和技术支撑。