Modeling and Analysis of Interfacial Bonding and Load Transfer in SWNT-Reinforced Composites

摘要

A fundamental understanding of the mechanisms and magnitude of interfacial bonding and load transfer between carbon nanotubes and polymer matrices is critical for developing high performance nanotube-reinforced composites. Molecular dynamics (MD) simulation is an effective approach to investigate nanoscale interfacial phenomena. In this study, MD simulation models of the pullout of nanotubes were utilized to investigate the energy of material systems and to characterize interfacial shear strength in SWNT/polymer composites. The interfacial bonding and load transfer behaviors between the different SWNTs' configurations (open ends, capped ends, functionalized ends) were also examined. Additional theoretical calculations were performed to determine the effect of sidewall functionalization of the SWNTs on interfacial shear strength. The calculations revealed the effects of the different tube configurations on interfacial shear strength. The results indicated that the interfacial shear strengths are only 50~60MPa for the nanotubes with different end configurations there is no chemical bonding between tubes and resin matrix. The results of loading transfer analysis show that more than 600MPa interfacial shearing strength is needed to reach the full mechanical potential of (10,10) SWNTs with a length of 500nm and a tensile strength of lOOGPa. Approximate 15% of the carbon atoms on the nanotube sidewall must be functionalized. The results of the MD simulation were also compared with available experimental results and observations.