Multifunctional cotton fabrics with graphene/polyurethane coatings with far-infrared emission, electrical conductivity, and ultraviolet-blocking properties

In order to introduce multifunctional properties into flexible cotton fabric, graphene and waterborne anionic aliphatic polyurethane composites were prepared and then deposited on the surface of the fabric substrate through facile pad-dry-cure process. The fabrics thus obtained were characterized by scanning electron microscopy and Fourier transform infrared spectroscopy, and their functional properties such as far-infrared emission, electrical conductivity, and ultraviolet (UV) blocking were studied. The coating process enhanced the far-infrared emissivity up to 0.911 in the wavelength range of 4-18 μm. In addition, the ultraviolet protection factor (UPF) of the fabric with 0.8-wt% graphene could reach 500, up to 60-fold higher than that of pristine cotton fabric (UPF 8.19), and its electrical resistivity was decreased from 1.15 × 107 to 2.94 × 10−1 Ω m, which is almost 8 orders of magnitude. The fabrics have also been found to be stable even after 10 cycles of laundering.