Modeling of graphene-polymer interfacial mechanical behavior using molecular dynamics
Modeling of graphene-polymer interfacial mechanical behavior using molecular dynamics
复制标题
DOI：
10.1088/0965-0393/17/1/015002
复制
发表时间：
2009-01-01
影响因子：
1.8
通讯作者：
Hammerand, Daniel C.
中科院分区：
文献类型：
--
作者：
Awasthi, Amnaya P.;Lagoudas, Dimitris C.;Hammerand, Daniel C.
碳纳米管(CNT)聚合物基复合材料作为结构材料表现出良好的性能，需要寻找合适的本构模型来预测其宏观行为。确定这种材料均一化响应的可靠性取决于准确捕捉纳米管和聚合物基质之间的界面行为的能力。在这项工作中，使用分子动力学模拟，使用一致价力场(CVFF)来描述原子相互作用，研究了聚乙烯和石墨烯之间的纳米尺度的负载转移，选择了一个模型系统来表征碳纳米管和聚合物基质之间的力分离行为。对开启和滑动两种模式进行了分离研究，并对每种模式的粘结区参数，如峰值牵引力和分离能进行了评估。还研究了拉伸和压缩对滑模分离的影响。利用不同大小的计算域和不同的边界条件进行了尺寸相关性研究，以获得具有代表性的体积元素并连接到连续统级属性。这些结果为建立连续介质长度尺度的微观力学模型奠定了基础，该模型可用于确定包含界面现象的整体材料响应。
Carbon nanotube (CNT) polymer-matrix composites exhibit promising properties as structural materials for which appropriate constitutive models are sought, to predict their macroscale behavior. The reliability of determining the homogenized response of such materials depends upon the ability to accurately capture the interfacial behavior between the nanotubes and the polymer matrix. In this work, molecular dynamics simulations, using the Consistent Valence Force Field (CVFF) to describe the atomistic interactions, are used to study nanoscale load transfer between polyethylene and a graphene sheet, a model system chosen to characterize the force-separation behavior between CNTs and the polymer matrix. Separation studies are conducted for both opening as well as sliding modes and cohesive zone parameters such as peak traction and energy of separation are evaluated for each mode. Studies are also carried out to investigate the effect of tension and compression on sliding mode separation. Size dependence studies are conducted utilizing different sizes of the computational domain and different boundary conditions, to obtain the representative volume element and connect to continuum level properties. These results set the stage for continuum length-scale micromechanical models which may be used in determining the overall material response, incorporating interfacial phenomena.