Stretchable thermoplastic polyurethane/single-walled carbon nanotube masterbatch nanocomposites with enhanced electrical conductivity and thermal properties

Abstract

A thermoplastic polyurethane (TPU)/single-walled carbon nanotube (SWCNT) nanocomposite was developed using a twin-screw extrusion process followed by injection molding. This study aimed to enhance the properties of TPU by incorporating a SWCNT masterbatch, with a polyol ester serving as the carrier resin. The electrical conductivity, rheological behavior, mechanical performance, and thermal properties of the TPU/SWCNT nanocomposites were systematically evaluated. The incorporation of the SWCNT masterbatch significantly improved the electrical conductivity of the TPU nanocomposites. With SWCNT loading levels below 0.6 wt%, the viscosity and processability of the nanocomposites were maintained. However, a noticeable decrease in viscosity was observed when the SWCNT content exceeded 0.6 wt%. The tensile and storage modulus of the nanocomposites increased, attributed to the stiffness and reinforcing effects of SWCNTs. Despite a slight reduction in tensile strength and elongation at break upon SWCNT addition, the tensile properties of the TPU/SWCNT nanocomposites at a loading of 0.4 wt% remained well-suited for strain sensor applications. The polyol ester in the SWCNT masterbatch facilitated the uniform dispersion of carbon nanotubes within the TPU matrix and enhanced the nucleation ability of SWCNTs, contributing to improved performance characteristics.