摘要
聚合物基复合材料的微观结构与宏观性能之间存在密切的关联性,对其建立起结构-性能的联系,在工程应用和材料设计中有着重要的意义。通过分子动力学模拟方法探究了从低温环境(100 K)到玻璃化转变温度(T_g)的温度范围内,单壁碳纳米管(SWCNTs)对环氧树脂基体弹性模量的提高效果,并从微观结构角度分析了影响机制。发现随着温度的升高,体系内聚能密度(E_(coh))不断减小,自由体积分数(V_f)不断增加,共同导致了弹性模量随温度的升高而降低。SWCNTs对基体弹性模量的提高是由于其在任一温度点均明显提高了基体的E_(coh)和径向分布函数,对基体V_f增长的抑制效果也随温度的升高而更加明显。弹性模量的实验结果验证了模拟的计算和分析结果,证明了分子模拟方法预测材料宏观性能的可靠性。
According to the corresponding relationships between microstructure parameter and macro performance in high-low temperature of polymer composites,the predication of the structure-performance relationship need to be concerned in engineering application.In this paper,the effects of single-walled carbon nanotubes(SWCNTs)on elastic modulus of epoxy resin matrix from low temperature(100 K)until their T g were investigated through molecular dynamics simulation.Then mechanisms of microstructure parameter were investigated in depth.The results show that with the increase of temperature,the ever-reduced cohesive energy density(E coh)and ever-increasing free volume fraction(V f)result in the decreasing of elastic modulus.Molecular simulation reveales that E coh and radial distribution function(F radial)of epoxy matrix are significantly increased as the addition of SWCNTs.Compared to the neat epoxy matrix,the inhibitory effect of SWCNT on the ascent of the V f of the matrix at high temperatures was also more pronounced with increasing temperature.Elastic modulus in experiments verifies simulation results,which proves that molecular simulation was reliability to predict the macroscopic properties of polymer composites.
作者
张文卿
李浩
隋刚
ZHANG Wen-qing;LI Hao;SUI Gang(State Key Laboratory of Organic-Inorganic Composites,Beijing University of Chemical Technology, Beijing 100029,China)
出处
《玻璃钢／复合材料》
CSCD
北大核心
2018年第11期15-20,共6页
Fiber Reinforced Plastics/Composites
基金
国家自然科学基金(U1664251
51873011)
关键词
碳纳米管
环氧树脂
弹性模量
分子模拟
结构-性能关系
carbon nanotubes
epoxy resin
elastic modulus
molecular simulation
structure-performance relationship
作者简介
张文卿(1993-),女,博士研究生,主要从事纳米增强增韧环氧树脂/碳纤维复合材料及分子模拟方面的研究;通讯作者:隋刚(1972-),男,博士,教授,主要从事纳米复合材料、功能树脂基复合材料方面的研究,suigang@mail.buct.edu.cn。
