Formation of novel and crack free nanocomposites based on sol gel process for corrosion protection of copper

► Sol gel coatings were developed on copper based on Phenyltrimethoxysilane (PTMS). ► Crack free coatings were obtained after the addition of sodium montmorillonite (MMT). ► Anti-corrosive properties of coatings were improved by addition of MMT nanoparticles. ► Addition of nanoparticle significantly decreases the water penetration ability.