丁羟推进剂黏结体系中增塑剂迁移的分子模拟

Molecular Simulation on Plasticizer Migration in the Bond System of HTPB Propellant

为克服固体推进剂中增塑剂与黏结体系之间加速老化实验手段的不足,构建了增塑剂和黏结体系的分子模型。利用分子模拟方法在COMPASS力场下分析了增塑剂癸二酸二辛酯(DOS)在由端羟基聚丁二烯(HTPB)和异佛尔酮二异氰酸酯(IPDI)组成的黏接体系中的相容性和扩散性。用无定形动力学方法计算组分的溶度参数,判断DOS与HTPB、IPDI的相容性。结果表明,DOS与HTPB、IPDI相容性较好。这与由共混方法计算的结合能得到相容性好的结论一致;通过分子动力学方法模拟计算得到增塑剂DOS在黏结体系(HTPB-IPDI)中的扩散系数为1.2×10-7cm2/s。

To overcome the disadvantage of experimental means, the molecular models of plasticizer and the bond system were constructed. The compatibility and the diffusibility of dioctyl sebaeate （DOS） in the bond system of hydroxyl terminated polybutadiene （HTPB） and isophorone diisocyanate （IPDI）, were investigated by molecular simulation method under the COMPASS （condensed-phase optimized molecular potentials for atomistic simulation studies）force field. The solubility parameters of components were calculated by amorphous cell dynamics method and the compatibitity of DOS with HTPB and IPDI was judged. The results show that.. DOS is well compatible with HTPB and IPDI, which is in good agreement with the conclusion of compatibility drawn by the bind energy gained by blend method. The diffusion coefficient of DOS in the bond system of HTPB and IPDI by the simulation method of molecular dynamics is 1.2×10 ^-7cm^2 · s^- 1.