Molecular level analysis of carbon nanofiber reinforced polymer composites

Abstract

The present study focuses on modeling of carbon nanofibers (CNFs) and evaluating the effect of their reinforcement in polypropylene (PP) matrix. A novel approach for modeling of CNF has been explained in this study. Molecular dynamics (MD) simulation has been used to study the effect of CNF volume fraction (Vf) and aspect ratio (l/d) on mechanical properties of CNF-PP composites. Materials Studio 5.5 has been used as a tool for finding the modulus and damping in composites. CNF composition in PP was varied by volume from 0 to 16%. Aspect ratio of CNF was varied from l/d = 5 to l/d = 100. Results have also been obtained for longitudinal loss factor (η11). To the best of the knowledge of the authors, till date there is no study, either experimental or analytical, which predicts η11 for CNF-PP composites at nanoscale. Hence, this will be a valuable addition in the area of nanocomposites. Results show that with only 2% addition by volume of CNF in PP, E11 increases by 748%. Thereafter, the increase is at a lower rate. Increase in E22 is very less in comparison to the increase in E11. With increase in CNF aspect ratio (l/d) till l/d = 60, the longitudinal loss factor (η11) decreases rapidly. Thereafter, the decrease is smaller. Results of this study are in agreement with those predicted by Shinichi et al.