摘要 |
The present invention relates to a multi-component system for making impressions which contains (a) at least one compound having at least two alkenyl groups; (b) at least one organohydrogenpolysiloxane; (c) at least one hydrosilylation catalyst; characterized by containing (d1) at least one polymeric compound having at least one alkynyl group and/or (d2) at least one compound having at least one Si-OR structural unit, wherein R=H, alkyl, alkoxyalkyl or acyl; and when a compound (d2) having at least one Si-OR structural unit is contained, (e) at least one condensation catalyst and/or condensation cross-linking agent. After the mixing of the components, the materials according to the invention cure in two steps. At the beginning of mixing, the mixture, in a first state, has a mixer-suitable consistency, whereupon the mixture undergoes transition to a heavier-bodied second state due to condensation reactions of SiOR groups and/or hydrosilylation reactions of alkynyl groups with SiH groups, followed by transition to a third solid, elastic state following curing through a hydrosilylation reaction of alkenyl groups with SiH groups. The invention also relates to mixtures and components comprising further ingredients, as well as methods for the preparation of impressions.
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