Physical Origin of Distinct Mechanical Properties of Polymer Tethered Graphene Nanosheets Reinforced Polymer Nanocomposites Revealed by Nonequilibrium Molecular Dynamics Simulations,Macromolecular Theory and Simulations

当前位置： X-MOL 学术 › Macromol. Theor. Simul. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Physical Origin of Distinct Mechanical Properties of Polymer Tethered Graphene Nanosheets Reinforced Polymer Nanocomposites Revealed by Nonequilibrium Molecular Dynamics Simulations
Macromolecular Theory and Simulations ( IF 1.8 ) Pub Date : 2021-08-19 , DOI: 10.1002/mats.202100044
Xu Zhang ₁ , Jialiang Chen ₂ , Tianxi Liu _{1,

3}

Affiliation

A non-equilibrium deformation simulation based on standard molecular dynamics is employed to reveal the physical origin of distinct mechanical properties of polymer nanocomposites (PNCs) reinforced by polymer tethered graphene nanosheets (P/G-T). The effect of tethered polymer length (L) and interaction strength on the mechanical properties, including tensile stress, modulus, and yield strength, are examined. The simulation results show that the P/G-T systems exhibit improved mechanical properties as L and interaction strength increases. The strengthening in attractive interaction between matrix polymer and tethered polymer has a better effect on mechanical properties than that between P and graphene nanosheets. It is found that the bond orientation and nonbonding potential is of crucial importance in determining the mechanical properties of the P/G-T nanocomposite systems. The calculations of radial distribution functions and mean-squared displacement are further performed to reveal the physical origin of enhanced mechanical properties, suggesting that the stronger interfacial interactions will induce the closer packing distance with smaller free volume, higher polymer chain entanglement, and higher restriction of polymer chain movement, which synergistically contribute to the improvement in the mechanical properties. The results may provide useful guidance for promoting the development and practical application of the advanced PNCs with excellent performance.

中文翻译：

非平衡分子动力学模拟揭示聚合物束缚石墨烯纳米片不同机械性能的物理起源增强聚合物纳米复合材料

采用基于标准分子动力学的非平衡变形模拟来揭示由聚合物束缚石墨烯纳米片 (P/GT) 增强的聚合物纳米复合材料 (PNC) 的不同机械性能的物理起源。检查了束缚聚合物长度 ( L ) 和相互作用强度对机械性能的影响，包括拉伸应力、模量和屈服强度。模拟结果表明，P/GT 系统表现出改善的机械性能，如L和互动强度增加。基质聚合物和束缚聚合物之间的吸引力相互作用的加强对力学性能的影响比P和石墨烯纳米片之间的效果更好。研究发现，键的取向和非键势对于确定 P/GT 纳米复合材料体系的机械性能至关重要。进一步进行径向分布函数和均方位移的计算以揭示增强机械性能的物理原因，表明更强的界面相互作用将导致更紧密的堆积距离，更小的自由体积，更高的聚合物链缠结和更高的限制聚合物链运动，这协同地有助于改善机械性能。

更新日期：2021-08-19

点击分享查看原文

点击收藏

阅读更多本刊最新论文本刊介绍/投稿指南11