Simulation of the thermomechanical behavior of graphene/PMMA nanocomposites via continuum mechanics

Abstract

Purpose The purpose of this paper is to simulate and investigate the thermomechanical properties of graphene-reinforced nanocomposites. Design/methodology/approach The analysis proposed consists of two stages. In the first stage, the temperature-dependent mechanical properties of graphene are estimated while in the second stage, using the previously derived properties, the temperature-dependent properties of graphene-reinforced PMMA nanocomposites are investigated. In the first stage of the analysis, graphene is modeled discretely using molecular mechanics theory where the interatomic interactions are simulated by spring elements of temperature-dependent stiffness. The graphene sheets are composed of either one or more (up to five) monolayer graphene sheets connected via van der Waals interactions. However, in the second analysis stage, graphene is modeled equivalently as continuum medium and is positioned between two layers of PMMA. Also, the interphase between two materials is modeled as a medium with mechanical properties defined and bounded by the two materials. Findings The mechanical properties including Young’s modulus, shear modulus and Poisson’s ratio due to temperature changes are estimated. The numerical results show that the temperature rise and the multiplicity of graphene layers considered lead to a decrease of the mechanical properties. Originality/value The present analysis proposes an easy and accurate method for the estimation of the temperature-dependent mechanical properties of graphene-reinforced nanocomposites.

Thermomechanical Behavior of Bone-Shaped SWCNT/Polyethylene Nanocomposites via Molecular Dynamics

“…Theoretical approximations for analyzing the thermomechanical properties of NCs include molecular dynamics (MD) [ 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 ], molecular mechanics (MM) [ 17 , 18 ], and continuum mechanics (CM) [ 19 ] based methods. In addition, multi-scale numerical schemes have recently been proposed, which combine atomistic simulations such as MD or MM with other CM methods such as FEM in an effort to provide reliable predictions with low-computational cost [ 17 , 18 , 20 ]. Despite the fact that the MM and the CM formulations require significantly smaller computational efforts, the MD approaches seem to be more versatile and provide more accurate and reliable numerical solutions when investigating multiphase nanomaterial components in the nanoscale.…”

Thermomechanical Response of Fullerene-Reinforced Polymers by Coupling MD and FEM

“…All the above investigations have been realized via MD, which is a method that demands extensive computational power. Due to the high pre-processing and main-processing computational times required for analyzing material components at the nanoscale, several multiscale techniques [ 16 , 17 , 18 ] have been proposed that combine the benefits of molecular and continuum modeling. Characteristically, Montazeria and Rafii-Tabar [ 16 ] presented a combination of MD, molecular mechanics (MM), and the finite element method (FEM) that is capable of computing the elastic constants of a polymeric nanocomposite embedded with graphene sheets and carbon nanotubes at various temperatures.…”

“…Characteristically, Montazeria and Rafii-Tabar [ 16 ] presented a combination of MD, molecular mechanics (MM), and the finite element method (FEM) that is capable of computing the elastic constants of a polymeric nanocomposite embedded with graphene sheets and carbon nanotubes at various temperatures. Similarly, Tsiamaki and Anifantis [ 17 ] have utilized a multiscale model based on MM and FEM to analyze the thermomechanical behavior of graphene/PMMA nanocomposites. Recently, Giannopoulos [ 18 ] proposed a formulation combining MD and FEM to predict the mechanical behavior of fullerene-reinforced nylon-12; however, this was at room temperature only.…”