针对丁羟推进剂/衬层界面增塑剂的迁移问题,研究增塑剂的扩散特性。采用分子动力学方法模拟增塑剂在丁羟粘合剂体系中的运动,再通过爱因斯坦关系式求得扩散系数;采用对衬层加厚的粘接试件进行加速老化实验方法,再通过费克第二定律计算得到增塑剂的扩散系数;考察不同环境温度和不同增塑剂含量条件下癸二酸二辛酯的扩散系数的变化。分析认为,增塑剂在丁羟粘合体系高分子链段运动产生的间隙中,以“跳跃”方式发生空间位置迁移。结果表明,扩散系数模拟值和实验值基本一致,数量级为10-12m2/s;温度升高,增塑剂运动活性加强,有效活动空间增大,扩散系数增大;粘合体系与增塑剂的共容限量使得增塑剂含量大于3%时,模拟得到的扩散系数依次略有下降。分子动力学方法计算增塑剂扩散系数更具优势。 Aiming at the problem of the migration of the plasticizer in the butyrolactone / liner interface, the diffusion characteristics of the plasticizer were studied. Molecular dynamics simulation was used to simulate the movement of plasticizer in the system of butadiene and hydroxyl. The diffusion coefficient was calculated by Einstein’s relationship. The accelerated aging test was carried out on the bonded specimen with thickened lining. Diffusion coefficient of plasticizer was calculated by Fick’s second law. Differences of diffusion coefficients of dioctyl sebacate under different ambient temperatures and different plasticizer contents were investigated. The analysis shows that the plasticizer migrates in the position of “jumping ” in the space produced by the movement of the polymer chain segment of the polybutadiene system. The results show that the simulation values ​​of diffusion coefficients are in good agreement with the experimental values, and the order of magnitude is 10-12m2 / s. With the increase of temperature, the activity of plasticizer increases, the available space increases and the diffusion coefficient increases. Of the total allowable limit makes the plasticizer content is greater than 3%, the simulated diffusion coefficient decreased slightly in turn. Molecular dynamics method to calculate plasticizer diffusion coefficient has more advantages.