聚合物分子与官能化纳米管相互作用及扩散特性的分子动力学模拟

用全原子分子动力学方法研究典型聚合物分子（PE，PEO和PP）与碳纳米管（CNT）及官能化碳纳米管（FCNT）界面的相互作用及扩散特性.动力学模拟显示：—CH₃官能团具有减弱CNT与PE和PP的相互作用，但是，—CH₃官能化后的CNT与PEO之间确有增强作用.分析含氧官能团（—OH和—COOH）官能化的CNT与PE，PEO和PP的相互作用，可知含氧官能团的确具有增强表面相互作用的功能，而且含氧原子越多，相互作用就越强.此外，—CH₃，—OH，—COOH官能化后的CNT与PE，PP和PEO体系的总能量均减少，而且能量满足—COOH < —OH < —CH₃.分析非键相互作用势（库仑能和范德瓦尔斯能），可知库伦相互作用是增强界面相互作用的主要作用能.官能化后的CNT/PE，CNT/PEO，CNT/PP体系的扩散系数都明显减小，且扩散系数大小满足—COOH < —OH < —CH₃.

Interfacial Interaction and Diffusion Properties of Functionalized CNT/Polymer Systems: Molecular Dynamics Simulations

Molecular dynamics simulations are used to study interfacial interaction and diffusion properties of CNT/polymer chains. It shows that —CH₃ decreases interfacial interaction energies of PE/CNT and PP/CNT systems. However, interfacial interaction energy of CNT/PEO modified with —CH₃ is increased. Compare interaction energies between pure CNT and PE, PP and PEO, we found that the interfacial interaction energy increased as CNT modified with —OH and —COOH. And the strength satisfies —COOH<—OH. Besides, total energies of PE/CNT, PP/CNT and PEO/CNT modified with —CH₃, —OH and —COOH are reduced. The decrease rate follows rule: —COOH < —OH < —CH₃. Coulomb energy plays the main role in the non-bond energies rather than vdW energy. Moreover, diffusion coefficient of functional CNT/PE, CNT/PP and CNT/PEO are obviously reduced by the impose of function groups, and the diffusion coefficient of the polymer chains satisfy —COOH<—OH<—CH₃.