聚醚砜酮及其与ε-CL-20复合体系性能的分子动力学模拟

摘要

A new poly(phthalazinone ether sulfone ketone) (PPESK) was designed by introducing azide and amine into phthalazinone, and its effects on the stability and mechanical properties of ε-hexanitrohexaazaisowurtzitane (ε-CL-20) were studied.Based on COMPASS force field, the amorphous cell of PPESK was constructed and its density and glass transition temperature were studied.The molecular dynamics (MD) simulations of interface crystal model composed of four main growth face of ε-CL-20 and PPESK were performed, and the cohesive energy densities, binding energies and mechanical properties of PPESK/ε-CL-20 composite system were obtained.The results show that the density and glass transition temperature of PPESK obtained by calculation are accurate compared with literature.The difference of the solubility parameters (Δδ) between ε-CL-20 and PPESK is 8.512 (J/cm3)1/2, indicating that they have certain compatibility.The order of binding energy between PPESK and the main growth face of ε-CL-20 is (0 1 1) > (0 0 2) > (1 0-1) > (1 1 0).In which, the proportion of (0 1 1) face is 38.2% and it is the largest one;the mechanical coefficients of four kinds of PPESK/ε-CL-20 composite system are greatly decreased, indicating that the addition of PPESK can effectively reduce the rigidity and isotropy of ε-CL-20, and the plasticity of systems can be enhanced.%通过在二氮杂萘酮中引入叠氮基和氨基,设计了一种新型聚醚砜酮(PPESK),并研究了其对六硝基六氮杂异伍兹烷(ε-CL-20)稳定性和力学性能的影响.应用COMPASS力场,构建PPESK无定型晶胞并研究了其密度和玻璃化转变温度;对ε-CL-20的4个主要生长面与PPESK组成的界面晶体模型进行了分子动力学(MD)模拟,求得PPESK/ε-CL-20复合体系的内聚能密度、结合能和力学性能.结果表明,与文献相比,计算所得的PPESK密度和玻璃化温度较为准确;ε-CL-20与PPESK的溶度参数差值(Δδ)为8.512 (J/cm3)1/2,两者具有一定相容性;PPESK与ε-CL-20主要生长面的结合能大小依次为:(0 1 1) > (0 0 2) > (1 0-1) > (1 1 0),其中(0 1 1)为最大生长面,所占比例为38.2%;4种复合体系的力学系数均大幅度减小,表明PPESK的加入有效降低了ε-CL-20的刚性和各向同性,体系塑性增强.