【摘要】 为了探究硝酸羟胺基凝胶推进剂的凝胶化机制，采用分子动力学（MD），在分子水平上研究了聚丙烯酰胺（PAM）分子在硝酸羟胺/聚丙烯酰胺/甲醇/水凝胶推进剂体系中的微观行为、最终交联构型以及影响体系稳定性的氢键分布及其对体系动力学性质的影响。计算结果表明PAM分子主要通过分子间氢键相互作用形成相互作用节点，进一步促使分子链铺展并构建三维网状骨架。随着PAM质量分数从2.7%增加到10.7%,PAM分子间形成的氢键数目从11.98增加到109。范德华力相互作用和氢键共同驱动PAM分子进行自促进交联过程。硝酸羟胺中羟胺基团和硝酸根离子的径向分布呈双峰特性，PAM的引入减弱了第一峰的强度，因其通过交联“域”降低了局部相互作用和能量密度，从而提高了推进剂的稳定性。更多还原

【Abstract】 To explore the gel mechanism of hydroxylamine nitrate-based gel propellant, the molecular dynamics(MD) simulations were employed to investigate the microscopic behavior, final crosslinking configuration, and the hydrogen bonding distribution that influences the stability of the hydroxylammonium nitrate/polyacrylamide(PAM)/methanol/water propellant gel system of PAM molecules. Results show that PAM molecules primarily form interaction nodes through intermolecular hydrogen bonding interactions, further promoting the expansion of molecular chains and the construction of a three-dimensional network framework. As the mass fraction of PAM increases from 2.7% to 10.7%, the number of hydrogen bonds formed between PAM molecules increases from 11.98 to 109. Both Van der Waals force interactions and hydrogen bonding jointly drive a self-accelerating crosslinking process of PAM molecules. The radial distribution of hydroxylammonium groups and nitrate ions in hydroxylammonium nitrate shows a bimodal characteristic. The introduction of PAM weakens the intensity of the first peak, as it reduces local interaction and energy density by forming crosslinking "domains", thereby enhancing the stability of the propellant.更多还原