Organopolysiloxanes having aliphatically unsaturated radicals, the preparation thereof and the use thereof in crosslinkable materials

PCT No. PCT/EP96/05721 Sec. 371 Date Jun. 19, 1998 Sec. 102(e) Date Jun. 19, 1998 PCT Filed Dec. 19, 1996 PCT Pub. No. WO97/23548 PCT Pub. Date Jul. 3, 1997The invention relates to organopolysiloxanes which have aliphatically unsaturated radicals, are soluble to at least 80 wt % in organic solvents selected from xylene and toluol at a temperature of 25 DEG C. and a pressure of from 900 to 1100 hPa and contain at least one unit of the following formula (I) R1aR2-aSiO2/2, at least one unit of the following formula (II) R1bR3-bSiO1/2, at least one unit of the following formula (III) O1/2R2SiOxYRSiO2/2, and optionally at least one unit of the following formula (IV) O1/2R2SiOxYR2SiO1/2, in which: R can be identical or different and is a monovalent, substituted or unsubstituted, SiC-bonded, aliphatically saturated hydrocarbon radical. R1 can be identical or different and is a monovalent, SiC-bonded, substituted or unsubstituted, aliphatically unsaturated hydrocarbon radical, a is 0, 1 or 2, b is 0, 1, 2 or 3, x is 0 or 1 and y is a radical -(CR32)nCHR3- with at least two carbon atoms, where n is 0 or an integer from 1 to 3 and R3 is a hydrogen atom or is as defined for R, with the proviso that the organopolysiloxane includes at least one unit of the formula (II) where b is not 0. It also relates to the preparation of the organopolysiloxanes and the use thereof in crosslinkable materials.