某双基球扁药中DBP钝感剂的分布及扩散

Distribution and Diffusion of DBP Deterrent in a Double Base Oblate Spherical Propellant

采用显微红外光谱技术测试了某双基球扁药中邻苯二甲酸二丁酯(DBP)钝感剂的质量浓度分布,并采用液相色谱法验证了结果的可靠性;测定了某双基球扁药在71℃、28d的加速老化过程中,不同老化时间的DBP钝感剂质量浓度分布数据,并依据Fick第二定律的高斯解拟合分布曲线方程,推算出DBP钝感剂的扩散系数。结果表明,该双基球扁药中DBP钝感剂质量浓度由表及里呈指数规律下降,符合Fick第二定律的扩散模型,钝感层深度约60μm;通过DBP钝感剂质量浓度分布函数的三重积分获得双基球扁药中DBP钝感剂的总含量,与液相色谱测定值基本一致;DBP钝感剂的扩散系数在老化过程中不是一个恒定值:在0~3d的老化初期,DBP钝感剂的扩散速率相对较快,扩散系数为1.9×10^(-15)m^(2)/s;在3~28d的老化阶段,DBP钝感剂的扩散速率显著降低,扩散系数为5.2×10^(-16)m^(2)/s。

The concentration distribution of dibutyl phthalate(DBP)deterrent in a double base oblate spherical propellant was tested by FTIR microspectroscopy technique,and the reliability of the results was verified by liquid chromatography.The double base oblate spherical propellant was aged at 71℃for 28 d,and the concentration distribution of DBP deterrent with different aging time were obtained.The diffusion coefficients of DBP deterrent were calculated by fitting the distribution curve equation according to the Gaussian solution of Fick′second law.The results show that the DBP deterrent mass concentration in the propellant decreases exponentially from the surface inwards,which is in accord with the Fick′second diffusion model,and the diffusion depth of deterrent layer is about 60μm.The total DBP deterrent content in the propellant calculated by triple integral calculation of DBP deterrent distribution function is essentially in agreement with the value measured by liquid chromatography.The diffusion coefficient of DBP deterrent is not a constant value during the aging process:in the initial aging stage of 0-3d,the diffusion rate of DBP is relatively quick,and the diffusion coefficient is 1.9×10^(-15)m^(2)/s;in the aging stage of 3-28d,the diffusion rate of DBP deterrent is decreased significantly,and the diffusion coefficient is 5.2×10^(-16)m^(2)/s.