Functionalized coating materials based on inorganic-organic polymers

ORMOCER(R)s (ORMOCER(R) Trademark of Fraunhofer-Gesellschaft zur Forderung der angew and ten Forschung e.V.) as inorganic organic polymers synthesized by a two-step sol-gel processing method can be applied as thin transparent coatings on various substrates (polymers, metals, ceramics). The curing of ORMOCER(R)s is performed thermally (at temperatures below 200 degrees C) or by W-radiation. Their high abrasion resistance and good chemical stability led to several actual industrial applications. Beside mechanical protection functions (e.g. for sensitive polymer substrates) additional functionalities of ORMOCER(R) surfaces are investigated to find new application areas. This paper presents two additional surface functions of abrasion resistant ORMOCER" coatings: Antiadhesive and antistatic properties. Incorporation of perfluorinated alkoxysilane compounds via sol-gel processing decreases the surface energy of the cured layer. Water as well as non-polar substances lose their adhesion to the surface, wetting is reduced, solutions are drained off and particles can be removed easily. By addition of polar and/or ionic compounds bearing hydrolyzable alkoxysilyl groups a scratch resistant antistatic coating for polycarbonate was developed. Compared to the uncoated substrate, the specific surface resistance was decreased from 10(15) to 10(8) Omega. Electrostatic charging is decreased and attraction of particles inhibited or reduced. The coatings are abrasion resistant and show very good adhesion even in a wet climate.