METHOD FOR PRODUCING AN AQUEOUS SILICONE EMULSION COMPOSITION

摘要

METHOD FOR PRODUCING AN AQUEOUS SILICONE EMULSION COMPOSITION According to the present invention, an aqueous silicone emulsion composition is produced as follows. A base emulsion is prepared from prescribed quantities of an essentially straight-chain organopolysiloxane with at least 2 silicon-bonded hydroxyl groups in each molecule, colloidal silica or alkali metal silicate, a curing catalyst, an emulsifier and water. After the pH is adjusted to 9 to 12 and ripened until an elastomer material is formed by the removal of water at room temperature, prescribed quantities of an epoxy-functional silane coupling agent or its partial hydrolysis product or its partial hydrolysis condensation product, a filler and a dispersant are added. The produced aqueous silicone emulsion composition bonds tightly to porous substrates in contact with it during curing and is therefore extremely useful as a coating or sealing material for various porous substrates.