聚合物纳米复合材料拉伸与剪切形变下的微观结构演变的分子动力学模拟研究

项目名称： 聚合物纳米复合材料拉伸与剪切形变下的微观结构演变的分子动力学模拟研究

项目编号： No.51503081

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 一般工业技术

项目作者： 沈建祥

作者单位： 嘉兴学院

项目金额： 20万元

中文摘要： 实时追踪聚合物纳米复合材料形变过程中其微观结构的演变是高分子材料科学中一直未能解决的科学难题，是探索和研究材料微观结构和宏观性能之间的定量关系的前提和基础，而传统的实验表征手段是很难触及材料微观结构演变的。本项目通过建立不同形状的填料填充的聚合物纳米复合材料的全原子及粗粒度模型，采用分子动力学模拟方法对聚合物纳米复合材料在拉伸和剪切下的微观结构演变进行研究。通过表征出模拟体系中存在的各种微观结构包括填料网络结构、填料聚集体分形结构、分子链搭建的远程填料网络结构等，实时追踪这些微观结构在简单形变以及动态形变过程中是如何演变的，并确定这些微观结构在外力形变下的稳定性差异。从而找出模拟体系的微观结构演变与宏观表现之间的有效关联，提出一个解释和预测材料宏观性能的且普适度高的理论模型，为优化聚合物纳米复合材料的宏观力学性能提供科学的理论指导。

中文关键词： 分子动力学模拟；微观结构；分散与界面；结构与性能；纳米复合材料

英文摘要： The characterization of the micro-structural evolution of polymer nanocomposites (PNCs) under the deformations, which is the precondition and foundation of understanding the quantitative structure-property relation, cannot be real-time traced by traditional experimental tools such as SEM, TEM, and AFM etc. In order to understand how the micro-structures change to influence the macro-properties, this project is expected to investigate the micro-structural evolution of PNCs under the tensile deformation and shear deformation using the molecular dynamics simulation method. In this project, the atomistic and coarse-grained models of PNCs filled with different nanoparticles such as spherical carbon black or silica, graphene sheets and carbon nanotubes will be established. Various micro-structures in the PNCs such as the filler network structure, fractal nanostructure of fillers and filler network mediated by polymer segments will be characterized systematically and comprehensively. By performing the tensile deformation and shear deformation through the non-equilibrium molecular dynamics simulations (NEMD), the micro-structural evolution is hoped to be real-time on-line monitored. Therefore, by combining the changes of micro-structure with the macro-properties, the quantitative or qualitative structure-property relation will be investigated. This project may shed some light on how to solve the structure-property relation problem to predict the macro-properties of PNCs, and is believed to provide some guidance on optimizing the macro-properties of PNCs.

英文关键词： molecular dynamics simulation;micro-structure;dispersion and interface;structure-property relation;nanocomposite