ATOMISTIC SIMULATION TO STUDY THE EFFECT OF DEFECTIVE NANO FILLER ON INTERFACIAL STRENGTH OF NANOCOMPOSITE

Abstract

Aim of this dissertation was to develop an atomistic model to study the effect of defective Nanofiller (h-BN nanosheet) on interfacial strength of polymer (high density polyethylene) based nanocomposite. In this study molecular dynamics-based simulations were performed in conjunction with reactive force field. Reactive force field was utilized to simulate the interatomic interactions between atoms in h-BN nanosheet and polyethylene. The cross interaction between the nanosheet and polymer matrix was captured using the Lennard Jones non-bonded interactions. Molecular dynamics-based simulations were performed to capture the uni-axial tensile deformation in polyethylene reinforced with pristine and defective (bi-crystalline) h-BN nanosheets. In second stage of simulations, a traction separate law (TSL) was also extracted to multiscale the problem at micro level. The interfacial shear force (ISF) and interfacial shear stress (ISS) between h-BN nanosheets and PE matrix were evaluated. Through atomistic simulations, it is projected that the tensile strength of neat PE can witness a nearly 32% enhancement when reinforced with approximately 4.7% pristine h-BN nanosheets. The efficacy of any nanofiller in reinforcement hinges on the strength of the interface between the matrix and the reinforcement material. In this context, the interface between h-BN and PE is construed to be governed by non-bonded van der Waals interactions. Moreover, the investigation extends to assess the impact of defective h-BN nanosheets on their reinforcing capabilities within the PE matrix. The simulations reveal that specific geometrical defects exhibit a favorable influence on the interfacial properties between h-BN and PE. These findings are poised to pave the way for leveraging defective nanofillers in crafting cost-effective nanocomposites for diverse applications in the future.