丁羟推进剂模型体系中键合剂作用机理的分子模拟研究

为研究不同键合剂在丁羟(HTPB)推进剂中作用机理,采用分子动力学(MD)方法和COMPASS力场对固本填料(Al/Al_2O_3)晶面、键合剂及HTPB所组成的层面模型进行了模拟计算,求得了吸附能与静态力学性能,研究了键合剂对体系力学性能的影响;在303 K温度下对推进剂中氧化剂分解气体O_2和H_2O在键合剂膜层中的扩散进行了模拟,探讨了键合剂对推进剂抗老化性能影响.结果表明,键合剂加入能够增强固体填料同HTPB界面吸附能力,使体系弹性系数增强,刚度增加;而键合剂膜层对气体扩散的阻碍能力也同提高体系抗老化性能趋势一致.

Molecular Simulation on Mechanism of Bonding Agents in HTPB Solid Propellant Model

In order to explore the effect of bonding agents on the mechanical properties and chemical ageing resistance of hydroxyl-terminated polybutadiene (HTPB) solid propellant, molecular dynamics method and COMPASS force field were adopted to simulate the adsorption energy and mechanical properties of the interfaces constructed by HTPB, bonding agents and crystal faces of Al and Al/Al₂O₃. Then simulations were applied to estimate the diffusion coefficients of H₂O and O₂ in different bonding agents membranes. The results show that bonding agents increases the interaction of solid grain and HTPB, and improves elastic modul of Al/HTPB layer showing the enhancement of HTPB system rigidity. The trend of ability of restraining the diffusion of gas is consistent with experimental chemical ageing resistance of different bonding agents.