MOLDING TOOL FOR PRODUCING PLASTIC FOAM PARTS HAVING A HYBRID POLYMER COATING FOR IMPROVING THE DEMOLDING PROCESS, AND SILICIC ACID (HETERO) POLYCONDENSATE AS A COATING MATERIAL FOR THE MOLDING TOOL

摘要

The invention relates to a molding tool for curing elastomers, in particular polyurethane polymers, characterized by a coating that is composed of or comprises a silicic acid (hetero) polycondensate in which hydrocarbon groups bound to silicium atoms via carbon atoms are present and is applied to the interior of the mold, with the following specifications: (i) a portion of silicium atoms that is equal to at least 20% of the sum of all silicium and metal atoms contains groups bound via carbon atoms; (ii) 10% at most of all silicium atoms bear more than two groups bound by carbon atoms; (iii) 20-100 mol% of the groups bound by carbon atoms are selected from one or several alkyl, aryl, aryl alkyl and alkyl aryl groups (A), the carbon chain of which can optionally be interrupted by oxygen atoms if said carbon chain has at least three carbon atoms; (iv) at least 10% of all silicium atoms are components of pre-condensed structures in which at least three silicium atoms that each contain two groups (A) are directly linked together by oxygen atoms, and/or up to 30% of all groups (A) are substituted with fluorine. The invention further relates to the production and to the use thereof, and to a specific silicic acid (hetero) polycondensate that is suitable for producing the coating for the molding tool.