Ambient Temperature Curing Coating Composition
Published November 4, 2008
An ambient temperature curing coating composition was recently patented. A polysiloxane has a formula where each R1 is selected from alkyl, aryl and alkoxy groups having up to six carbon atoms, reactive glycidoxy groups and OSi(OR3)3 groups. Each R3 independently has the same meaning as R1. Each R2 is selected from alkyl and aryl groups having up to six carbon atoms. N is selected so that the molecular weight of the polysiloxanes is in the range of from 500 to about 2000. An alkoxysilyl-functional acrylic polymer is prepared by copolymerizing at least three different olefinically unsaturated monomers wherein at least one of the monomers is an alkoxysilyl-functional olefinically unsaturated monomer. Optionally water is used as a curing agent. The coating composition comprises more than 70% by weight of solids and has a viscosity of below 20 Poise at 25°C and is substantially free of colloidal silica.