Water repellent finishing on eri silk fabric using nano silica

Nano silica was extracted from rice husk and applied on eri silk fabric to impart water repellency. The efficiency of the water repellency was evaluated with water contact angle, water absorbency and spray test methods. In order to enhance the water repellent properties, a silicone-based polymer was also applied. The effect of nano silica coating on the physico-mechanical properties of the eri silk fabric was studied using standard methods. SEM, FTIR and EDX techniques were used for the confirmation of presence of nano silica on silk fabric. The results inferred the nano silica imparted hydropholic property to eri silk fabric, which was further enhanced to superhydrophobic by the incorporation of silica polymer. The nano silica coating slightly enhanced the whiteness and brightness of eri silk fabric. Other mechanical parameters like bending rigidity and crease recovery angle were found to be intact. The higher concentration of nano silica caused a slight reduction in fabric tensile strength.