Exceptional interfacial properties of structurally defected CNT/polymer nanocomposites: A molecular dynamics study

초록

The interfacial properties of structurally defective single-walled carbon nanotube (CNT) embedded polymeric nanocomposites are quantitatively characterized through molecular dynamic simulations. Three different kinds of point defects including single vacancy, single adatom, and Stone-Wales are generated to pristine CNT respectively and nanotube pulling out simulation in CNT/PP nanocomposites unit cells are carried out using molecular mechanics calculation. The CNT-polymer interaction energy, CNT pulling out energy, interfacial bonding energy, and interfacial shear strength of modeled nanocomposites are derived and compared with each other according to the types and number of defect. Vacancy defect decreases the interfacial shear strength linearly as the number of defect increases whereas adatom and Stone-Wales defects increase the interfacial shear strength due to the strong adsorption characteristics of the heptagonal carbon ring in these two defect types with the polymer chains close to the nanotube. Those exceptional dependencies on the types of structural defect also can be observed from the other interfacial properties and local deformation of the matrix phase induced by the pulled CNT. © 2012 AIAA.