Synthesis and Characterization of Non-Fluorine Aqueous Super Water Repellent Agent

Abstract

Fakir droplet or superhydrophobic state on fiber surfaces are usually obtained by fluorochemical treatment or convoluted surface modification. In this work we obtain aqueous water repellent agent via facile method with the absence of solvent and fluorochemical compound. Treated fabric has contact angle in the range of 160o (Superhydrophobic) and water repellency rating as 80 by AATCC 22-2005. Fabric retains water repellency rating as 50 after 20 times of washing cycle. As proven by SEM micrographs, superhydrophobicity of fabric's surface is achieved by imparting lotus-like siloxane network on each fiber. We observed no interconnection between modified fibers which ensure soft hand feeling of superhydrophobic fabric. Polydimethylsiloxane roles as siloxane backbone and long carbon chain of silane modifiers are incorporated to lower the intrinsic surface tension of polydimethylsiloane. The most optimum curing condition was achieved at 160oC for 10 minute curing time. FTIR analysis shows evidence of PDMS modification by noticeable additional peak at 1641.22 cm^(-1), 1565.12 cm^(-1), 1480 cm(-1), 1180 cm(-1), 3400 cm^(-1) and 779 cm(-1), which correspond to the structure of modifier. XRF analysis shows Si attachment to the fabric prior to the application of water repellent agent and Si remains attached after 20 times of washing cycle.