▎ 摘　　要

Nanocomposites of waterborne polyurethane (WPU) containing graphene oxide sheets (GO) were prepared by an in-situ polymerization method at low temperature. The morphology and interface structure were characterized by atomic force microscopy (AFM), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Without under-going complicated functionalization processes, GO can be finely embed into a WPU matrix and present high degree of orientation at high GO contents, due to the formation of chemical bonds and hydrogen bonding. From the Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and dynamic mechanical analysis (DMA) results, incorporation of GO exists in two ways and shows inverse effects. At a content of 2.0 wt.% GO loading, the tensile elastic modulus of the GO-WPU film increased by 193% to neat WPU. The nanocomposites also displayed 30 degrees C higher thermal stability than WPU in thermogravimetric (TG) curves. This environment-friendly method may pave the way to design graphene-based polymer composites.