Thermal stability, surface wettability and mechanical behavior of highly ordered ZnO-doped thermoplastic polyurethane films with hierarchically porous structures

In this paper, the effect of ZnO nanoparticle on thermal, microstructure, mechanical behavior, superhydrophobicity of thermoplastic polyurethane (TPU), ZnO/TPU composite materials with doped-ZnO nanoparticles were obtained via a solution blending method. The results show that the melting temperature region in soft segments of ZnO/TPU composite materials was the transition temperature region. The added ZnO slightly enhances the crystalline slipped of ZnO/TPU composite materials, and effectively hinder the transfer of high temperature small gas molecules. Due to the added ZnO nanoparticles, the microphase separation and ordered structures in TPU are reduced. In TPU, and between TPU and ZnO nanoparticles, there are variations in electron density at hard phase and soft phase interfaces. The good ZnO/TPU composites exhibit high water repellence with water contact angle of ~157°. The prepared ZnO/TPU nanocomposites show mechanical properties that are superior to those of pristine TPU. Tensile strength and storage modulus increase by 47.1% and 39.8% at ZnO loading values of 10 wt%. The results indicate that thermal behavior, microstructure, superhydrophobicity and the mechanical behavior of TPU composite materials can be enhanced by the doped ZnO.