Preparation of hexadecyltrimethoxysilane-modified silica nanocomposite hydrosol and superhydrophobic cotton coating

The hexadecyltrimethoxysilane(HDTMS)-modified silica (H-SiO2) nanocomposite hydrosol was prepared via water-based sol-gel reaction with methyltrimethoxysilane (MTMS) and HDTMS as precursors under alkaline condition in the presence of surfactant. The influences of base catalyst amount and surfactant concentration on the particle size and distribution of H-SiO2 nanocomposite hydrosol were analyzed. The obtained H-SiO2 nanocomposite was characterized by particle size analyzer, Fourier-transform infrared spectrometry (FTIR), thermal gravimetric (TG) and field emission scanning electron microscopy (FE-SEM), respectively. The H-SiO2 nanocomposite hydrosol was applied to coat onto the cotton fabric sample via one-step process. The cooperative action of rough surface structure due to the silica nanoparticles and the low surface energy caused by long-chain alkylsilane in the H-SiO2 nanocomposite coating provided the treated cotton fabric with excellent superhydrophobicity.