Water-free dewaxing of grey cotton fabric using supercritical carbon dioxide
The journal of Supercritical Fluids
Grey cotton shows low water wettability owing to contamination of the fibre surface with hydrophobic non-cellulosic impurities, such as waxes. This study investigated the efficiency of supercritical carbon dioxide (scCO2) water-free treatment for dewaxing grey cotton pile fabric to improve its hydrophilicity. The wettability of the virgin grey fabric was initially 14,400 s, and this value increased to 10,800 s upon treatment in pure scCO2 compared to 1200 in scCO2 containing acetone. The addition of polyoxyethylene lauryl ether to scCO2 containing acetone dramatically enhanced the water wettability to 6 s. Fourier-transform infrared (FT-IR) analysis of the change in the surface chemical composition of the fabric suggested the removal of wax by treatment in scCO2 containing acetone and polyoxyethylene lauryl ether. The study revealed that scCO2 is an alternative waterless method for improving the wettability of grey cotton fabrics.
Grey cotton, supercritical fluid, CO2