The research and application of modified silica sol for superhydrophobic cotton fabrics

No-fluorine superhydrophobic modified silica sol was prepared based on n-dodecyltrimethoxysi- lane and tetraethoxysilane by sol-gel technique at ambient temperature.The prepared silica sol was applied on pure cotton fabrics by dip-pad-cure method.The particle size measurement result indicated that the obtained particles were mainly distributed between 5 nm and 8 nm.The silica element was detected on the treated cotton fabric surface by energy dispersive spectroscopy.Contact angles were measured and the water contact angle of the treated cotton fabric was 151°for 5μL water droplet compared with 0°of the untreated fabric.The result of the scanning probe microscope showed that the roughness of the treated cotton fiber was drastically increased compared with the original cotton fiber.The increased roughness and the introduction of low surface energy chemicals account for the superhydrophobicity and this wetting was in accord with Wenzel model.