基于分子链演化的NEPE推进剂基体超弹本构模型  

The Hyperelastic Constitutive Model of NEPE Propellant Matrix Based on Molecular Chain Evolution

作　　者：刘俊 梁爽 刘向阳[2] 郜婕 LIU Jun;LIANG Shuang;LIU Xiang-yang;GAO Jie(School of Aerospace Engineering,Huazhong University of Science and Technology,Wuhan 430070,China;School of Aerospace Engineering,BeijingInstitute of Technology,Beijing 100081,China;The 41st Institute of the Fourth Academy of CASC,Xi′an 710025,China)

机构地区：[1]华中科技大学航空航天学院,湖北武汉430070 [2]北京理工大学宇航学院,北京100081 [3]中国航天科技集团有限公司四院四十一所,陕西西安710025

出　　处：《含能材料》2024年第5期518-527,共10页Chinese Journal of Energetic Materials

摘　　要：为了揭示硝酸酯增塑聚醚(NEPE)推进剂基体内高分子链结构演化与超弹性力学行为间的构效关系,采用多尺度方法,对复杂变形状态下NEPE推进剂基体内的高分子链演化过程及其表征模型进行了研究。首先,在基体黏合剂、固化剂和增塑剂等组分微观模型的基础上,通过对基体体系的分子动力学模拟,发展了描述复杂变形状态下交联链和自由链构形演化的动力学模型。随后,基于统计力学理论对系统自由能中交联链和自由链演化的贡献进行了定量表征,并建立了考虑高分子链交联、缠结效应的超弹本构模型。最后,结合NEPE推进剂基体胶片准静态拉伸实验数据对本构模型进行了验证。结果表明,相较于经典Arruda-Boyce超弹本构模型,基于物理机制的本构模型中本构参数具有真实的物理意义,可以通过物化实验进行参数标定,能较好地预测复杂变形状态下的基体超弹性行为,从而为推进剂基体力学性能的调控和组分优化提供模型支持。To reveal the relationship between the evolutions of polymer chains within the NEPE propellant matrix and the hyper-elastic mechanical behavior,a multiscale approach was adopted to investigate the evolution behavior and characterization mod-el of polymer chains under different deformation states.Firstly,based on the microscopic models of components such as matrix adhesives,curing agents,and plasticizers,a dynamic model describing the evolution of cross-linked and free chain configura-tions under complex deformation states was developed through molecular dynamics simulation of the matrix system Subsequent-ly,the free energy contributed bycrosslinked and free chains was quantitatively characterized based on statistical mechanics,and a hyperelastic constitutive model considering the cross-linking and entanglement effects was established.Finally,the devel-oped constitutive model was validated by using the quasi-static tensile experimental data of NEPE propellant matrix samples.Compared with the classical Arruda-Boyce model,the constitutive parameters in the present model have real physical signifi-cances and can be obtained by experimental methods,which enables the present model to better predict the hyperelastic behav-ior of the propellant matrix under different deformation states,and thus provide model for the regulation of mechanical proper-ties and component optimization of propellant matrix.

关 键 词：推进剂基体 超弹性 本构模型 物理机制 分子动力学 高分子链密度 

分 类 号：TJ5[兵器科学与技术—军事化学与烟火技术] V512.3[航空宇航科学与技术—航空宇航推进理论与工程]