Interfacial properties of defective carbon nanotube/polypropylene composites: a molecular dynamics approach

Carbon nanotube (CNT) reinforced nanocomposites have garnered a lot of attention as a very appealing alternative to traditional composite materials owing to their mechanical, chemical, thermal, and electrical characteristics. The interfacial properties of pristine CNT-polypropylene (CNT-PP) composites were evaluated in this study using molecular dynamics (MD) simulations. The pull-out process was performed for varying volume fractions (4%-14%) of the CNT. The maximum interfacial shear stress (IFSS) was obtained at a volume fraction of 6% for (6,6) armchair SWCNT. MD simulations have been performed on the nanocomposites to investigate the impact of Stone-Wales (SW) and vacancy defective CNT on the IFSS of the composites. The IFSS showed a maximum enhancement of 2.25% when 4.16% degree defects were loaded on the SWCNT in case of SW defects whereas the IFSS degraded by 11.97% for the same degree defect in case of vacancy defects. The presence of SW defects in the CNT enhanced the interfacial properties of composites whereas the CNTs with vacancy defects deteriorated the IFSS of the nanocomposite.