HMX和HMX／HTPBPBX的晶体缺陷理论研究  

A Theoretical Study on Crystal Defect of HMX and HMX/HTPB PBX

作　　者：马秀芳[1] 肖继军[1] 黄辉[2] 李金山[2] 肖鹤鸣[1] 

机构地区：[1]南京理工大学化学系分子与材料计算研究所,南京210094 [2]中国工程物理研究院化工材料研究所,绵阳621900

出　　处：《化学学报》2008年第8期897-901,共5页Acta Chimica Sinica

基　　金：中国工程物理研究院重大基金(No.2004Z0503)资助项目

摘　　要：建立空位和掺杂点缺陷模型,用分子动力学(MD)方法,研究晶体缺陷对β-环四亚甲基硝胺(HMX)和β-HMX/HTPB(端羟基聚丁二烯)高聚物粘结炸药(PBX)的力学性能和爆炸性能的影响.结果表明,相对于HMX"完美"晶体(1)考察缺陷晶体(2和3),以及相对于HMX完美晶体基PBX(1)考察缺陷PBX2和PBX3,均发现弹性系数和(拉伸、体积、剪切)模量下降,导致体系刚性减弱,延展性和韧性增强.这与在基炸药HMX晶体(1,2和3)中分别加入HTPB高聚物粘结剂形成PBX1,PBX2和PBX3呈现类似的相应的变化趋势和效果.此外,研究表明,爆炸性质也依赖于体系的组成和结构.因加入的是低能高聚物,故PBX(1),PBX(2)和PBX(3)的爆热、爆速和爆压均比相应的基炸药(1,2和3)低,即晶体(1)>PBX(1),晶体(2)>PBX(2),晶体(3)>PBX(3).PBX(1),PBX(2),PBX(3)与对应基炸药(1,2,3)的爆速和爆压取相同变化次序,亦即PBX(1)>PBX(2)>PBX(3)对应于晶体(1)>晶体(2)>晶体(3).这些计算结果和规律对PBX配方设计显然具有指导作用.Abstract Based on the established models with vacancy and doping point defects, molecular dynamics （MD） simulation has been used to explore the effects of crystal defects on mechanical and detonation properties of perfect β-HMX crystal and β-HMX based polymer-bonded explosives （PBX）, in which the hydroxyl terminated polybutadiene （HTPB） is used as a binder. The mechanical properties were obtained by analyzing MD simulation trajectories and the detonation properties were calculated using a corrected Kamlet-J equation. It was found that compared to the elastic coefficients and modulus （tensile, bulk and share） of perfect HMX crystal （1）, those of the defect crystals （2 and 3） were decreased and the values of Cauchy pressure and K/G were increased gradually. These account for rigidity weakening comparatively, ductibility and tenacity strengthening comparatively step by step. The mechanical properties of their corresponding three PBXs follow the same changing trends. In addition, detonation property depends on the constitutes and structures of systems. Owing to the inert polymer, the detonation properties of three PBXs decrease com- paratively to those of the corresponding three based HMX crystals, that is, crystal（1）〉PBX（1）, crystal（2）〉 PBX（2） and crystal（3）〉PBX（3）. The order of detonation velocity and pressure of PBXs 1, PBXs 2 and PBXs 3 is PBX（1）〉PBX（2）〉PBX（3）, coinciding with the one of base explosives （1, 2 and 3）, crystal（1）〉 crystal（2） 〉crystal（3）. All these results and rules can provide guidance to the design of PBX formulations.

关 键 词：晶体缺陷 掺杂 高聚物粘结炸药 分子动力学 力学性能 爆轰性能 

分 类 号：O77[理学—晶体学] TQ564[化学工程—炸药化工]