Superhydrophilic surface modification of fabric via coating with nano-TiO2 by UV and alkaline treatment

Abstract Increasing the hydrophilicity of poly(ethylene terephthalate) (PET) fabric has been an ongoing research goal. In this study, a rapid, environmentally friendly, and highly efficient method for modifying the surface of PET fabric is presented. In a solution of 30 g/L nano-TiO 2 , 50 g/L H 2 O 2 , and 30 g/L NaOH, PET fabric was modified to become superhydrophilic by ultraviolet (UV) irradiation (1000 W) for only 30–40 min. The water contact angle of the modified PET fabric was decreased to 0°, and the water absorption rate of the modified PET fabric was increased from 85% to 104%. The capillary rise height increased from 0.2 cm to 6.2 cm, and the spraying rating decreased from 4 to 1. The crease recovery angles of modified PET fabrics were reduced by only 1.2–8.8%. The mechanical and physical properties of the modified PET fabric remained good. Compared to the surface of unmodified PET fabric, scanning electron microscopy showed that the surface of the modified PET fiber was rough and covered by a layer of other materials. Fourier transform infrared spectroscopy showed the materials on the surface of modified PET fibers likely included COOH and OH groups. X-ray diffraction demonstrated the formation of crystalline material. Finally, differential scanning calorimetry thermograms showed that the modification process slightly improved the thermostability of PET fibers.