Starting from an organohydrogenpolysiloxane having at least two hydrogen atoms directly bonded to the silicone atoms, an organohydrogenpolysiloxane is obtained in which part of the silicon-bonded hydrogen atoms have been converted into organic groups and the remaining silicon-bonded hydrogen atoms are left unreacted. The starting organohydrogenpolysiloxane is brought to the partial addition reaction with less than equivalent amount of an organic unsaturated compound having aliphatic double bond in the molecule in the presence of a platinum catalyst, and the reaction mixture is subjected to distillation while the platinum catalyst is deactivated by added benzothiazole or derivatives thereof, thus providing for the production of the organohydrogenpolysiloxane of the invention in reproducibly in high yield. The compounds are useful as crosslinking agents in the manufacture of various silicone products.
Organopolysiloxanes having a viscosity of at least 100 mPa.s at 25.degree. C. and having both SiC-bonded acryloxyalkyl groups and Si-bonded hydrogen atoms in the same molecule are described herein. These are preferably prepared by adding an allyl alcohol to diorganopolysiloxanes containing an Si-bonded hydrogen atom in each of their terminal units, then esterifying the hydroxyl groups of the resultant reaction product with acrylic acid and subsequently equilibrating the resultant diorganopolysiloxanes containing an SiC-bonded acryloxypropyl group in each of their terminal units, with organo(poly)siloxanes containing an Si-bonded hydroxyl group in each of their terminal units, in which the organo(poly)siloxanes contain methylhydrogensiloxane units and optionally diorganosiloxane units of the formula as well as other organo(poly)siloxanes. These organopolysiloxanes may be crosslinked by high energy radiation and are useful as adhesive-repellent coatings for paper or for manufacturing optical glass fibers.
Organopolysiloxanes having a viscosity of at least 100 mPa.s at 25.degree. C. and having both SiC-bonded acryloxyalkyl groups and Si-bonded hydrogen atoms in the same molecule are described herein. These are preferably prepared by adding an allyl alcohol to diorganopolysiloxanes containing an Si-bonded hydrogen atom in each of their terminal units, then esterifying the hydroxyl groups of the resultant reaction product with acrylic acid and subsequently equilibrating the resultant diorganopolysiloxanes containing an SiC-bonded acryloxypropyl group in each of their terminal units, with organo(poly)siloxanes containing an Si-bonded hydroxyl group in each of their terminal units, in which the organo(poly)siloxanes contain methylhydrogensiloxane units and optionally diorganosiloxane units of the formula as well as other organo(poly)siloxanes. These organopolysiloxanes may be crosslinked by high energy radiation and are useful as adhesive-repellent coatings for paper or for manufacturing optical glass fibers.
A method for preventing unwanted continued polymerization with aging of a polymer, e.g., a silicone gel, which was catalytically cured comprises treating the cured polymer with a catalytic deactivating agent or stabilization of cured resin.
An organopolysiloxane of the formula ##STR1## in which x=0 to 500, y=5 to 500, z=5 to 500, R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 independently of one another, represent a saturated and/or unsaturated, optionally also branched alkyl radical having 1 to 4 C atoms, and/or an aryl radical having 6 to 9 C atoms, which may also be optionally alkyl-substituted, R.sub.7 represents an alkyl radical having 6 to 18 C atoms, and in which in each case at least 3% of the radicals bonded to Si are R.sub.7 and H. They are reactive with substrates and thus wash-resistant.
An adhesive silicone composition comprising (A) an alkenyl group-containing organopolysiloxane, (B) an organohydrogen-polysiloxane having at least three hydrogen atoms each directly bonded to a silicon atom in a molecule, (C) a compound having at least one aliphatic unsaturated group and at least two phenyl skeletons in a molecule, and (D) a platinum catalyst is well adhesive to both metals and reins, and even to difficult-to-adhere resins such as nylon, polycarbonate and acryl resins.
