有机极性小分子/ACM复合体系氢键结构和阻尼性能分子动力学模拟

Moleculardynamics simulation of hydrogen bond structure and damping properties of organic polar small molecules/ACM composite system

采用分子动力学模拟对受阻酚AO-70/丙烯酸酯橡胶(ACM)和受阻胺GW-622/ACM体系的氢键结构和阻尼性能进行研究。AO-70与ACM的溶解度参数更接近,AO-70/ACM体系更稳定,其相容性优于GW-622/ACM体系。径向分布函数和氢键分析表明有机极性小分子/ACM复合体系中均存在分子间和分子内氢键,随AO-70和GW-622含量增多,产生的氢键数目增加,成键概率增大。AO-70和GW-622含量相同时,分子间氢键数量相同,但AO-70与ACM的相容性更佳,AO-70/ACM体系阻尼性能更优。有机极性小分子/ACM复合体系中分子间氢键数量增多,自由体积分数降低,内聚能密度增加,链段更密集,断、成键过程能耗增加,阻尼性能提升。模拟结果可为高阻尼复合材料氢键结构与阻尼性能关系的相关研究提供参考。

Molecular dynamics simulation is used to study the hydrogen bond structure and damping properties of hindered phenol AO-70/acrylate rubber(ACM)and hindered amine GW-622/ACM system.The solubility parameters of AO-70 are closer to ACM,the AO-70/ACM system is more stable,and its compatibility is better than that of the GW-622/ACM system.Radial distribution function and hydrogen bond analysis show that intermolecular and intramolecular hydrogen bonds are existed in both systems.As the content of AO-70 and GW-622 increases,the number of hydrogen bonds generated increases,and the probability of bonding increase.When the content of AO-70 and GW-622 are the same,the number of intermolecular hydrogen bonds are the same in both composite systems,but the compatibility of AO-70 and ACM is better,and thus AO-70/ACM system possess better damping performance.The increased number of intermolecular hydrogen bonds in the composite system induce the increase of intermolecular interaction force,decrease of free volume fraction,increase of cohesive energy density.Furthermore,the molecular chains are stacked tighter,the energy consumption in the process of breaking and forming bonds increase,and the damping performance improve.The simulation results provide some references for studying the relationship between hydrogen bond structure and damping performance of high-damping organic composite materials.