Non-fluorinated superhydrophobic finish of cotton fabric

The aim of this study is to prepare water repellent cotton fabric via sol-gel method using non-fluorinated additives,thus avoiding the potential risk for environment from fluoroalkyl compounds.Superhydrophobic cotton fabric was successfully obtained first by dip-coating the silica sol,then the fabric was modified with alkyltrialkoxysilanes through self-assembly methods.Silica sols with different sizes were prepared by controlling the concentration of ammonia.The influence of silica nanoparticle sizes,structure and concentration of alkyltrialkoxysilanes,and washing cycles on water contact angle were discussed.Superhydrophobic cotton fabric with water contact angle of 155° can be achieved by this method.Scanning electron microscopy was used to observe the cotton fabric surfaces treated with and without silica sol.Physical and mechanical properties of cotton fabric showed a slight change after treatment.