Patent ID: 8110697

Claim:
A process for the production of polymerizable silicones of the formula P—Y-Sp-Si(R 2 ) n (OSiR 1 3 ) (3-n) (I), comprising the following steps: (a) admixing disiloxane (1) of the formula (R 1 ) 3 SiOSi(R 1 ) 3 (II) with acetic acid (2) and sulfuric acid (3) and optionally acidic catalyst (4), (b) at a temperature of from −20° to 0° C., metering in a substituted alkoxysilane (5) of the formula P—Y-Sp-Si(R 2 ) n (OR 3 ) (3-n) (III), (c) following a phase separation, separating off an acid phase from a product phase, (d) adding 0.02-1.0 mol of hexamethyldisilazane (6), based on 1 mol of alkoxysilane (5) to the product phase, (e) after filtering off a resulting salt from the product phase, removing readily volatile constituents and distilling to recover a polymerizable silicone product, and (f) optionally filtering the product, where R 1 are each identical or different and are hydrogen or an optionally substituted monovalent hydrocarbon radical having 1 to 18 carbon atoms, R 2 are each identical or different and are hydrogen or an optionally substituted monovalent hydrocarbon radical having 1 to 18 carbon atoms, R 3 are each identical or different and are alkyl radicals having 1 to 18 carbon atoms optionally substituted with alkoxy groups, Sp is a single bond or a divalent hydrocarbon radical having 1 to 8 carbon atoms, Y is a single bond or —O—, P is an acryloxy, methacryloxy, vinyl or allyl radical, and n is 0, 1 or 2.