PETN基PBX结合能和力学性能的理论研究

PETN(季戊四醇四硝酸酯)是著名的硝酸酯类猛炸药,用量子力学(QM)、分子力学(MM)和分子动力学(MD)方法,计算模拟其与高聚物组成的PBX(高聚物粘结炸药)的结合能和力学性能.以AM1-MO法和MM方法取PETN与系列高聚物的尺寸匹配原子簇模型,经几何全优化计算,发现两种方法求得的结合能彼此线性相关.对PETN超晶胞及其与系列氟聚物组成的双组分PBX,实施COMPASS力场下的分子动力学(MD)周期性模拟,求得其弹性系数、拉伸模量、体模量、剪切模量和泊松比,发现添加少量高聚物确能有效改善炸药的力学性能.

Theoretical study on binding energies and mechanical properties of PETN-based PBX

PETN(Pentaerythrol Tetranitrate) is a well-known ester high explosive.Quantum mechanics(QM),molecular mechanics(MM) and molecular dynamics(MD) were employed to calculate and simulate the binding energies and mechanical properties of PETN-based PBXs.The dimension matched atomic cluster models for PETN and a series of polymers were fully optimized using AM1 and MM method,and it is found that the calculated binding energies by different methods are linearly correlated to each other.Molecular dynamics has been used to simulate mechanical properties of PETN crystal and the PBXs involving PETN and a series of fluorine containing polymers.Elastic coefficients and effective isotropic mechanical properties such as tensile moduli,bulk moduli,shear moduli,and poisson's ratios are determined.The results indicate mechanical properties of PETN can be effectively improved by blending with fluorine containing polymers in small amounts.