Inorganic-organic hybrid hydrophilic coatings were fabricated using the organo alkoxysilane and organic hydrophilic monomer by way of the sol-gel method. To fabricate the hydrophilic coatings, these two method were used in this investigation. 3-Glycidoxypropyl-trimethoxysilane(GPTS) and 3-Aminopropyl-triethoxysilane(APTES) were used as organoalkoxysilanes to fabricate hydrophilic coatings. Epoxy ring in GPTS can be changed into the glycol group in acid or base condition, and can react with amine group in APTES, these can increase the hydrophilic property of the coatings. HCl and CH3COOH as acid catalysts did not effectively change epoxy ring into glycol group, so the hydrophilic property of the coatings slightly increased. As the concentration of H2SO4 and APTES in the sol increased, the hydrophilic property of the coatings increased, so the contact angles between water droplet and coatings decreased and the times at which fogging appeared on the coatings lengthened.
2-Hydroxyethylmethacrlyate(HEMA) was used as a organic hydrophilic monomer to increase hydrophilic property of the coating.
And 3-Methacryloxypropyl-trimethoxysilane(MPTS) was chosen as the inorganic network precursor and the methacrylate in MPTS can be polymerized with HEMA by dibenzoylperoxide(DBPO) which is a thermal polymerization initiator. AS HEMA contains the hydroxy(OH) group, the hydrophilic property of the coatings increased with increasing HEMA content in the sols. By the addition of 4wt % polyethylene oleyl ether (Brij 96) to the sol, the hydrophilic property of the coatings extremely increased, so water droplet on the coatings completely wetted and fogging was not detected.
