Fabrication process of 2-dimensional nanomaterial reinforced polymer nanocomposites and their properties

Abstract

The polymer materials are well known for their specific properties, such as lightweight, flexibility, chemical composition and cheap prices. Monolithic polymers generally lack the mechanical properties required of engineering materials. Researchers have overcome many of the mechanical limitations of monolithic polymers by blending them with fillers and/or reinforcing additives such as fibers, whiskers, particles, or nanoparticles.

Although many types of filler have been investigated, the emergence of two-dimensional (2D) materials or molecules spearheaded the development of polymer nanocomposites. 2D materials have unique mechanical, thermal, electrical, and optical properties and are particularly interesting as novel reinforcing fillers in polymer nanocomposites. However, when blended into a fluid polymer matrix, the large surface area of most 2D nanomaterials causes them to aggregate via van der Waals interactions. Achieving a stable, uniform dispersion of nanomaterial in the polymer matrix is vital to realizing the full potential of a given polymer nanocomposite.

In this research, graphene nanoplatelets (GNPs) and boron nitride nanoplatelets (BNNPs) were incorporated into an epoxy polymer matrix to yield a nanocomposite material with enhanced mechanical and thermal properties. Each of the nanomaterials underwent both covalent and non-covalent functionalization in order to minimize aggregation and maximize interfacial bonding between the nanomaterial and the polymer matrix. Functionalized GNP/epoxy nanocomposites exhibited a 94.3% increase in Young’s modulus, 140% increase in fracture toughness and a 894% increase in thermal conductivity. The BNNP/epoxy nanocomposites exhibited 84.2% increase in Young’s modulus, 170% increase in fracture toughness and a 10-fold enhancement in thermal conductivity.

The simple and scalable functionalization processes described herein facilitate the development of other 2D nanomaterial-based polymer nanocomposites with enhanced mechanical and thermal properties.