Sol-gel coating including silica based material with pendent functional groups.
A coating compn. for hydrophilizating surfaces, esp. for coating fuel cell bipolar cells comprises a silica-based material including plurality of functional groups such as urea or propylurea, ionic or ionizable groups and could be applied onto a substrate by polymg. by hydrolysis a preliminary prepd. sol-gel compn. contg. a functionalized silica precursor. Thus, mixing 1 wt. part of 1 N aq. soln. HCl, 2 wt. parts N-(triethoxysilylpropyl)urea and 1 wt. part tetramethoxysilane, hydrolyzing this soln., dilg. with water and spraying the resulting sol-gel compn. onto fuel cell component gave a layer having thickness 2 - 20 μm, which could be crosslinked by heating in air at 85 - 120°. [on SciFinder(R)]