Method for preparing floride-free super-hydrophobic cotton fabric

The invention provides a preparation method of fluoride-free super-hydrophobic cotton fabrics, pertaining to the technical field of water repellent finishing of cotton fabrics. The preparation method is characterized in that the concrete steps comprise: 3ml to 6ml of ammonia water with a mass concentration of 25wt percent to 28wt percent is added into 50ml to 100ml of ethanol and stirred. 5ml to 6ml of N-tetraethyl silicate is added in a dropwise manner and aged for 30min to 80min to obtain silica sol; the cotton fabric is immersed in the silica sol, dipped and rolled, and then dried at 60 DEG C to 100 DEG C for 1min to 5min; and the cotton fabric is immersed in alkane siloxane hydrolyzate, dried at room temperature and roasted for 30min to 120min in an oven which is preheated to 120 DEG C to 160 DEG C. The preparation method is environmentally-friendly, convenient and effective and meets the requirements of ecotypic textiles; the preparation method has wide sources of raw materials and the contact angle of t