Characterizing nanotube–polymer interaction using molecular dynamics simulation

Abstract

Theoretical characterization of the interaction between Carbon nanotube (CNT) and surrounding polymer is presented in this article using molecular dynamics simulation. Firstly, isolated non-defected and defected CNTs are simulated. The reduction level in Young’s modulus of CNT is analyzed due to the induced vacancy defects in CNT nanostructure. Then, embedded CNT in polymer is simulated focusing on the CNT and polymer interaction. The effect of chemical functionalization on mechanical properties of nanocomposites is discussed at micro level. Stochastic analysis is conducted treating numbers of established covalent bonds between CNT and polymer and their positions as random parameters. Young’s modulus of the interphase region as an intermediate phase between CNT and polymer for continuum modeling is extracted. It is revealed that increasing numbers of transverse covalent bonds between CNT and polymer, Young’s modulus of the nanocomposites decreases arisen from induced vacancy defects in CNT. Although functionalization can improve the interfacial shear strength between CNT and polymer, it has a disadvantage in reducing Young’s modulus of the interphase region leading to weak stress transferring from resin to CNT.