叠氮增塑剂与GAP黏合剂的相容性模拟计算

Simulation Calculation Research on Compatibility of Azide Plasticizers and GAP Binder

叠氮含能化合物在提高推进剂能量、改善燃烧性能、降低特征信号等方面优势明显，研究叠氮增塑剂与GAP的相容性可以促进叠氮含能化合物在推进剂中的应用。对6种叠氮含能化合物的生成热、玻璃化转变温度等进行了计算分析，探讨了它们作为含能增塑剂的使用性能。通过分子动力学模拟，发现6种叠氮化合物对内聚能密度和溶解度参数的贡献以范德华作用力为主，其贡献值约为静电力贡献值的1．0～3．0倍。计算得到的目标叠氮化合物的溶解度参数与分子结构中的极性基团存在一定的正相关性，即极性基团含量越高，溶解度参数值越大。模拟模型中N100在GAP中的混溶均匀性都没有IPDI和MDI好，但GAP／N100、GAP／IPDI、GAP／MDI的溶解度参数均与纯GAP的相近。叠氮增塑剂DEGBAA与GAP、GAP／N100、GAP／IPDI、GAP／MDI之间的互溶性较理想，PEAA和TMNTA次之。DEGBAA的乃和黏度都较低，更适合作GAP基推进剂的含能增塑剂。

The azide energetic compounds have significant superiorities of increasing energy of propellant, improving combustion performance, decreasing signature, and so on. Investigating the compatibility between azide plasticizer and GAP can promote the application of the azide energetic plasticizer in propellant. The heats of formation and glass transition temperatures of six azide energetic compounds were calculated and analyzed. The application performance of them as energetic plasticizers was discussed. By using the molecular dynamics simulation, it is found that the main contribution to the cohesive energy density and solubility parameter of six azide compounds is Van der Waals force, and the value contributed by Van der Waals force is 1.0 - 3.0 times of that contributed by electrostatic force. There is certain positive correlation between the calculated solubility parameter of the target azide compound and the polar group in its molecular structure, namely, the value of solubility parameter increases with the increase of the polar group content. In the simulated model, the mixed solution uniformity of N100 in GAP is less than that of IPDI and MDI in GAP, but the solubility parameters of GAP/N100, GAP/IPDI, GAP/MDI are all closed to that of the pure GAP. The miscibility of azide plasticizer DEGBAA with GAP, GAP/N100, GAP/IPDI, GAP/MDI is better, and followed by the PEAA and TMNTA. Because the Tg value and the viscosity of DEGBAA are all low, it is more suitable as an energetic plasticizer for GAP-based propellant.