Integrated Computational and Experimental Design of Ductile, Abrasion-Resistant Thermoplastic Polyurethane/Graphene Oxide Nanocomposites

Abstract

Polymer nanocomposites are widely studied for improving and developing novel materials. Incorporation of nanofillers in polymer matrices impart strong behavioral changes, with the extent of dispersion of fillers in polymers playing a key role. This not only limits the amount of filler one can incorporate but also often leads to enhancement of some material properties at the expense of others. Herein, for the first time, thermoplastic polyurethane (TPU) graphene oxide (GO) nanocomposites with improved abrasion resistance and ductility are produced by integrating mesoscale modeling and a solvent-free continuous and upscalable extrusion process. The role of GO in hard segment crystallization is established via dissipative particle dynamics simulations, which then informs processing in twin-screw extrusion involving extensional mixing elements to achieve desired deagglomeration and dispersion of GO. This approach allows a tough yet highly ductile composite suitable for high abrasion resistant applications to be produced. In comparison with composites obtained from conventional processing, ductility improved by more than 300%, strength increased by 80%, toughness enhanced by more than 500%, and abrasion resistance improved by 45%. Insights into the gradient of TPU hard block crystallinity, role of deagglomeration, and phase separation are also discussed.