An investigation on microscopic and mechanical properties of polyethylene/boron nitride graphene nanocomposites by DFT calculations

Abstract

In this paper, the molecular dynamics (MD) simulation is used to explore the mechanical properties of polyethylene (PE) /boron nitride (BN) graphene nanocomposite in the pressure range of 0–20 GPa and temperature range of 100–600 K. Parameters of the adsorption energy, Young's modulus, glass transition temperature and radius of gyration are analyzed. For the interaction between PE and BN-graphene, the constant adsorption energy is reached with the eight degree of polymerization. Meanwhile, the Young's modulus, bulk modulus, shear modulus and Poisson's ratio of PE/BN-graphene nanocomposite are all improved, where the PE/BN-graphene nanocomposite performs well in resisting the changes in volume and shape to reflect the enhanced mechanical effect of BN-graphene on polyethylene. The mechanical properties of the PE/BN-graphene nanocomposite during the pressurization process are strong enough without fracture, and the best performance is achieved at 18 GPa. BN-graphene heightens the glass transition temperature of the nanocomposite with the enhanced structural and thermal stability. Besides, friction and wear properties of the PE/BN-graphene are guaranteed according to the gyration radius diagram.