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Aim of this article was to investigate the effect of grain boundaries on the interfacial properties of bi-crystalline graphene/polyethylene based nanocomposites. Molecular dynamics based atomistic simulations were performed in conjunction with the reactive force field parameters to capture atomic interactions within graphene and polyethylene atoms, whereas non-bonded interactions were considered for the interfacial properties. Atoms at the higher energy state in bi-crystalline graphene helps in improving the interaction at the nanocomposite interphase. Geometrical imperfections such as wrinkles and ripples helps the bi-crystalline graphene in increasing the number of adhesion points between the nanofiller and matrix, which eventually improves the strength and toughness of nanocomposite. These outcomes will help in opening new opportunities for defective nanofillers in the development of nanocomposites for future applications.

Due to their exceptional properties, graphene and hexagonal boron nitride (h‐BN) nanofillers are emerging as potential candidates for reinforcing the polymer‐based nanocomposites. Graphene and h‐BN have comparable mechanical and thermal properties, whereas due to high band gap in h‐BN (~5 eV), have contrasting electrical conductivities. Atomistic modeling techniques are viable alternatives to the costly and time‐consuming experimental techniques, and are accurate enough to predict the mechanical properties, fracture toughness, and thermal conductivities of graphene and h‐BN‐based nanocomposites. Success of any atomistic model entirely depends on the type of interatomic potential used in simulations. This review article encompasses different types of interatomic potentials that can be used for the modeling of graphene, h‐BN, and corresponding nanocomposites, and further elaborates on developments and challenges associated with the classical mechanics‐based approach along with synergic effects of these nano reinforcements on host polymer matrix. This article is categorized under: Molecular and Statistical Mechanics > Molecular Mechanics Structure and Mechanism > Computational Materials Science Molecular and Statistical Mechanics > Molecular Dynamics and Monte‐Carlo Methods

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In this article, experimental and classical mechanics-based approaches have been used to study the reinforcing capabilities of hexagonal boron nitride (h-BN) nanosheets for polyethylene (PE)-based nanocomposites. Experiments were performed with h-BN nanoflakes and high-density polyethylene-based nanocomposites. Experimental results reported 27.0 and 64.1% improvement in tensile strength and Young's modulus for 5 wt % h-BN loading in PE, respectively. Experimental analysis helps in developing a micro-and macrolevel understanding of the mechanical behavior of BN/PE nanocomposites, whereas the strength of these nanocomposites is governed by interfacial properties. Interfacial properties can be easily captured using atomistic simulations such as molecular dynamics. Molecular dynamics-based atomistic models were developed to study the effect of aspect ratio, weight fraction, morphology, distribution of h-BN nanosheets, and strain rate loading on mechanical properties of the nanocomposite. A reactive force field was employed to simulate the mechanical behavior of polyethylene and h-BN nanosheets, whereas nonbonded interactions were used for simulating the interphase in nanocomposites. It was predicted from the simulations that the aspect ratio, weight fraction, geometry distribution of h-BN nanosheets (dispersed or stacked), and stain rate loading significantly affect the mechanical behavior of h-BN/ polyethylene-based nanocomposites. The results obtained from the molecular dynamics approach are in close agreement with the experimental results, and both the characterization techniques provide a complete analysis of h-BN/PE nanocomposites.

The objective of this investigation was to elaborate on the influence of grain boundaries on the interfacial thermal conductance between bi-crystalline graphene and polyethylene in a nanocomposite.

In this article, molecular dynamics based simulations were carried out to study the tensile behaviour of boron nitride nanosheets (BNNSs). Four different sets of Tersoff potential parameters were used in the simulations for estimating the interatomic interactions between boron and nitrogen atoms. Modifications were incorporated in the Tersoff cut-off function to improve the accuracy of results with respect to fracture stress, fracture strain and Young's modulus. In this study, the original cut-off function was optimised in such a way that small and large cut-off distances were made equal, and hence a single cut-off distance was used with all sets of Tersoff potential parameters. The single value of cut-off distance for the Tersoff potential was chosen after analysing the potential energy and bond forces experienced by boron and nitrogen atoms subjected to bond stretching. The simulations performed with the optimised cut-off function help in identifying the Tersoff potential parameters that reproduce the experimentally evaluated mechanical behaviour of BNNSs.

Due to their exceptional mechanical properties, thermal conductivity and a wide band gap (5-6 eV), boron nitride nanotubes and nanosheets have promising applications in the field of engineering and biomedical science. Accurate modeling of failure or fracture in a nanomaterial inherently involves coupling of atomic domains of cracks and voids as well as a deformation mechanism originating from grain boundaries. This review highlights the recent progress made in the atomistic modeling of boron nitride nanofillers. Continuous improvements in computational power have made it possible to study the structural properties of these nanofillers at the atomistic scale.