摘要
为探究不同硅烷偶联剂改性二氧化硅(SiO_(2))对间位芳纶体系性能的影响,本文选取KH550、KH560、KH570和KH792四种硅烷偶联剂对SiO2进行接枝改性,并基于Materials Studio软件构建改性SiO_(2)与间位芳纶(PMIA)的复合体系模型(SiO_(2)/PMIA),通过分子动力学模拟,系统分析不同硅烷偶联剂对复合体系模型的玻璃化转化温度、力学性能、界面结合能和均方位移等的影响。结果表明:KH550修饰体系的玻璃化转变温度为579 K,比未修饰SiO_(2)/PMIA体系提高27 K,弹性模量和体积模量分别提升至7.756 1 GPa和4.256 1 GPa,增幅分别达31.6%和37.1%,显示出优异的热稳定性和力学性能。在不同温度下,KH792和KH550修饰体系对PMIA链分子运动的抑制效果最佳,均方位移分别为8.12Å2和12.5Å2,在高温条件下具有更优异的稳定性。界面结合能和氢键数量分析表明,KH792和KH550修饰体系在提升SiO_(2)/PMIA界面结合强度方面具有突出效果,较未修饰SiO_(2)/PMIA体系分别提升了116.8%和123.52%。
To investigate the effect of different silane coupling agents modified silica(SiO_(2))on the properties of metaaramid systems,this study selected four silane coupling agents-KH550,KH560,KH570,and KH792-to graft modify SiO_(2).The composite system models(SiO_(2)/PMIA)of modified SiO_(2) and meta-aramid(PMIA)were constructed using Materials Studio software.Molecular dynamics simulation were conducted to systematically analyze the effects of different silane coupling agents on the glass transition temperature,mechanical properties,interfacial binding energy,and mean square displacement of composite system models.The results show that the glass transition temperature of the KH550 modified system is 579 K,which is 27 K higher than that of the unmodified SiO_(2)/PMIA system.The elastic modulus and bulk modulus increases to 7.7561 GPa and 4.2561 GPa,respectively,with an improvement of 31.6%and 37.1%,respectively,demonstrating excellent thermal stability and mechanical properties.At different temperatures,the KH792 and KH550 modified systems exhibit the strongest inhibition on the movement of PMIA chain molecules,with mean square displacements of 8.12Å2 and 12.5Å2,respectively,demonstrating superior stability under high temperature conditions.The analysis of interface binding energy and hydrogen bond number indicates that the KH792 and KH550 modified systems have outstanding effects on improving the interface bonding strength of SiO_(2)/PMIA,with an increase of 116.8%and 123.52%respectively compared to the unmodified SiO_(2)/PMIA system..
作者
刘博闻
赵旭
毕瀚文
杜昀泽
律方成
郭腾
孙泽坤
LIU Bowen;ZHAO Xu;BI Hanwen;DU Yunze;LÜFangcheng;GUO Teng;SUN Zekun(Hebei Key Laboratory for Safety Defense of Power Transmission and Transformation Equipment,North China Electric Power University,Baoding 071003,China)
出处
《绝缘材料》
北大核心
2025年第12期74-84,共11页
Insulating Materials
基金
国家自然科学基金青年科学基金项目(52407022)。
关键词
硅烷偶联剂
间位芳纶
接枝改性
分子动力学模拟
silane coupling agent
meta-aramid
grafting modification
molecular dynamics simulation
