摘要 |
The invention relates to a process for the preparation of finely divided rubbers (rubber powders) by precipitation from aqueous mixtures, which comprise filler in the form of suspensions, water-soluble salts of a metal of groups IIa, IIb, IIIa and VIII of the periodic table of the elements and a rubber latex (polymer latex), aqueous emulsions of a rubber or rubber solution, in which one or more organosilicon compound(s) containing at least one alkoxy group is or are dissolved or emulsified, optionally in the presence of a surface-active substance, in water, or the compounds mentioned are mixed directly, optionally with a surface-active substance, with an aqueous suspension of an oxidic or silicatic finely divided filler or a mixture of these fillers at a temperature of 10 to 60 ° C, preferably at room temperature, while stirring, the amount of this mixture envisaged for incoporation in the rubber, based on the filler content, in general being divided into two batches.
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