A Nanoscale Investigation of Mechanical, Thermal Stability and Electrical Conductivity Properties of Reinforced Thermoplastic Polyurethane/Graphene Nanocomposite

Abstract

In the current research work reinforcement of a thermoplastic polyurethane (TPU) polymer with graphene powder (G, in the form of particles) as a nanofiller material by in-situ and ex-situ mixing of various weight fractions of G is reported. In addition, investigation on the effect of the weight fraction of G on the mechanical properties of the resulting TPU/graphene (TPU/G) nanocomposites is conducted. A number of different preparation methods have been employed in order to investigate the influence of the preparation process on the resulting TPU/G nanocomposites. Solvent (wet) mixing and mechanical (dry) mixing processes have been used. Significant enhancement in compressive strength, melt flow index and electrical conductivity were observed by employing the different mixing processes when compared with the pure TPU polymer processed under similar conditions. However, dry mixing process has shown enhanced mechanical, viscosity and electrical properties compared to wet mixing process. Moreover, dry mixing process has led to the formation of TPU/G nanocomposites with the highest compressive strength at 0.1 wt% G compared with 0.5, and 1 wt % G. It is believed that the processing technique plays a vital role in producing the desired TPU/G nanocomposites and is also affected by the dispersion of graphene nanofiller particles within the TPU polymer matrix. These results may lead to the development of novel applications of TPU/G nanocomposites across different disciplines.