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为了预测高分子粘结剂端羟基聚丁二烯(HTPB)与增塑剂癸二酸二辛酯(DOS)、硝化甘油(NG)的相容性及HTPB/ 增塑剂共混物的玻璃化转变温度(Tg)和力学性能,在COMPASS力场条件下采用分子动力学(MD)模拟方法对相容体系 (HTPB-DOS)和不相容体系(HTPB-NG)进行了研究.结果表明,通过比较溶度参数差值(△δ)的大小可以预测HTPB与增 塑剂的相容性,即HTPB与DOS属于相容体系,而HTPB与NG不相容.通过温度一比容曲线可以得到HTPB、 HTPB/DOS与HTPB/NG的Tg分别为197.54,176.30和200.03 K.力学性能分析结果表明,添加DOS增塑剂后使HFPB 的弹性模量(E),体积模量(K)和剪切模量(G)下降,材料刚性减弱,柔性增强,力学性能得到改善.本模拟方法可以作为 预测聚合物/增塑剂共混物性能的有利工具,也可以为固体推进剂和高聚物粘结炸药的配方设计提供理论指导.“,”Two systems, one miscible (hydroxyl-terminated polybutadiene-dioctyl sebacate or HTPB-DOS) and the other immiscible (HTPB-nitroglycerine or HTPB-NG) were simulated by molecular dynamics (MD) simulations with the COMPASS force field for predicting properties of HTPB/plasticizer blends such as the compatibility of polymer binder and plasticizer, the glass transition temperature (Tg) and mechanical properties of polymer/plasticizer blends. Results show that HTPB/DOS is a miscible system but HTPB/NG is not miscible, which can be predicted by comparing the difference in the solubility parameters value (△δ). The Tg has been determined by the slope of the V-T simulation data, the Tg of HTPB, HTPB/DOS, HTPB/NG is 197.54, 176.30 and 200.03 K. respectively. Mechanical properties such as tensile modulus (E), bulk modulus (K) and shear modulus (G) can also be predicted by MD simulations. The mechanical properties can be ef- fectively improved by the addition of DOS plasticizer, which may provide a more flexible mixture, with a lower E, K, G and an increased ductility. Therefore, the method used in this work is a useful tool to provide properties of a given polymer/plasticizer blend. In addition, it is a promising technique to help screen solid propellants and polymer bonded explosive (PBX) formulations before experimental tests.