纳米结构零件注射成型过程的分子动力学模拟  

Molecular Dynamic Simulation of Injection Molded Nanostructures

作　　者：蒋炳炎[1] 周明勇[1] 鲁立君[1] 翁灿[1] 

机构地区：[1]中南大学高性能复杂制造国家重点实验室,湖南长沙410083

出　　处：《高分子材料科学与工程》2015年第9期122-126,共5页Polymer Materials Science & Engineering

基　　金：国家自然科学基金重大研究计划培育项目(91123012);中南大学中央高校基本科研业务费专项资金(2013zzts035)

摘　　要：纳注射成型中,聚合物熔体在纳米型腔中的充填质量以及纳米结构的脱模完好性是决定纳结构零件复制质量的关键因素。文中采用分子动力学方法,建立聚甲基丙烯酸甲脂(PMMA)与金属镍模芯的界面模型,研究PMMA的玻璃化转变温度(Tg),深入分析注射成型过程中分子链的运动规律以及充填过程中的密度分布、体系能量等构象统计规律,并探讨纳米结构在脱模后的变形情况。结果表明,分子模拟得到的Tg与实验结果相符;纳米结构的充填主要发生在保压阶段,其平均充填率为55.8%;纳米结构在脱模后出现了一定程度的弯曲变形,但仍能保持其整体形貌。There are two main factors that determine the replication quality of nanostructures during nano injection molding process： the filling quality of polymer melt in nano cavity and the integrity of nanostructures after demolding. In this paper, an interracial model between poly methyl methacrylate （PMMA） and nickel metal insert was built by molecular dynamics method. The movements of PMMA molecular chains and the glass transition temperature （Tg） of PMMA, together with the density distribution, energy and other statistical regularities during the filling process were investigated. Afterwards, the deformation of nanostructures after demolding process was investigated. The results show that the calculated Tg is correlated with existing practical results. The filling process of nanostructures occurs mainly in the packing stage, and the average filling rate is about 55.8%. Nanostructures bend in a certain degree after demolding, but still can maintain their overall morphology.

关 键 词：注射成型 纳米结构 充填机理 分子动力学 聚甲基丙烯酸甲酯 

分 类 号：TQ320.66[化学工程—合成树脂塑料工业]