Claims
- 1. A process for producing diorganopolysiloxane polymers having a viscosity from 1,000 to 200,000,000 centipoise at 25.degree. C. where at least one of the organo groups is an aliphatic or haloaliphatic radical of at least 3 carbon atoms or more consisting essentially of
- (a) reacting cyclic polysiloxanes of the formula
- (RR'SiO).sub.4
- at a temperature in the range of 0.degree. to 90.degree. C. in the presence of 5 to 300 parts per million of a catalyst selected from the class consisting of CsOH, and ##STR5## where R.sup.2 is selected from the class consisting of alkyl radicals of 1 to 8 carbon atoms, cycloalkyl radicals of 4 to 8 carbon atoms and phenyl, B is selected from the class consisting of nitrogen and phosphorous, R.sup.3 is selected from the class consisting of alkyl radicals of 1 to 8 carbon atoms, cycloalkyl radicals of 4 to 8 carbon atoms, phenyl, siloxane chains of the unit formula R.sub.a.sup.4 SiO.sub.(4-a)/2 and mixtures thereof where R.sup.4 is selected from the class consisting of monovalent hydrocarbon radicals and halogenated monovalent hydrocarbon radicals, a varies from 1.5 to 2.5 until equilibration is reached, and (b) neutralizing the catalyst in the reaction mixture after equilibrium has been reached where R is selected from the class consisting of methyl, ethyl, vinyl and phenyl, R' is R.sup.5 CH.sub.2 CH.sub.2 -- and R.sup.5 is a perfluoroalkyl radical of 1 to 6 carbon atoms.
- 2. The process of claim 1 wherein the catalyst is neutralized with an ingredient selected from the class consisting of phosphoric acid and of the formula, R.sub.b.sup.6 SiX.sub.4-b, where R.sup.6 is selected from the class consisting of alkyl radicals, cycloalkyl radicals, vinyl radicals and phenyl radicals, X is selected from the class consisting of bromine and chlorine, and b varies from 0 to 3.
- 3. The process of claim 1 wherein after step (b) further comprising heating the reaction mixture to 150.degree. to 200.degree. C. at a vacuum of 1 to 100 mm of Hg to strip off all volatiles so as to result in the desired product.
- 4. The process of claim 1 wherein the cyclic polysiloxanes are reacted with the catalyst for a period of time varying from 1/2 hour to 10 hours.
- 5. The process of claim 1 wherein the cyclic polysiloxanes and mixtures thereof contains less than 20 parts per million of trifunctional siloxanes, less than 200 parts per million of monofunctional siloxanes, and 0 to 5% by weight of other cyclic polysiloxanes and less than 10 parts per million of water.
Parent Case Info
This application is a continuation of parent application Ser. No. 463,435 filed Apr. 24, 1974 which is now U.S. Pat. No. 3,937,684.
US Referenced Citations (7)
Continuations (1)
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Number |
Date |
Country |
Parent |
463435 |
Apr 1974 |
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