Two Component Room Temperature Vulcanizable Silicone Rubbers

2 Two Component Room Temperature Vulcanizable Silicone Rubbers 

With room temperature vulcanizable two-component silicone rubbers, the polymer and the crosslinking component are mixed immediately before application. Two different crosslinking systems are used, one based on polycondensation and the other on polymer addition. 

In polycondensation systems, a poly(dimethylsiloxane) with hydroxy end-groups at either end and a viscosity of 10- to 10 mPa s is crosslinked with tetraalkoxysilanes, e.g. tetraethoxysilane, in the presence of a condensation-accelerating tin compound e.g. dibutyltin dilaurate. Since this hardening, in contrast with single component products, is not dependent upon water diffusion through the hardening mass, thick layers of such rubber systems can be crosslinked quickly and homogeneously. 

Room temperature hardenable vulcanizable two-component silicone rubbers are usually formulated as flowable materials. They contain reinforcing and extending fillers. Their flowability means that they are able to flow into the finest details of the to be reproduced item. After vulcanization a negative mold is produced, which is complete reproduction of the original in all its detail. This technology is utilized for the restoring and duplication of 

Room lemperalurc harticnabli, iwo-component rubbers arc crossliiikabic by  

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