Patent US4719276A successfully refreshed from Google Patents.
US4719276A
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Neutralization of catalyst in polymerization of polydiorganosiloxane
Assignee: Dow Silicones Corp
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Filing: 1986-10-27
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Granted: 1988-01-12
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Expires: 2006-10-27
Abstract
Abstract A high molecular weight polydiorganosiloxane, produced by the alkaline catalysis of dialkylcyclotetrasiloxane, has a lower --SiOH content when the catalyst is neutralized with a composition of the formula R' 3 SiOC(O)R" where R' is a hydrocarbon radical of from 1 to 6 carbon atoms inclusive and R" is a hydrocarbon radical of from 1 to 8 carbon atoms inclusive.
Inventors
- 👤 Leo F. Stebleton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 13:22
CPC Classifications
C; C08; C08G; C08G77/00; C08G77/04; C08G77/32
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
64 words
A method of neutralizing the catalyst used in the alkaline polymerization of diorganocyclosiloxane in which the neutralizing agent is a composition of the formula R' 3 SiOC(O)R", where R' is a hydrocarbon radical of from 1 to 6 carbon atoms inclusive and R" is a hydrocarbon radical of from 1 to 8 carbon atoms inclusive which comprises admixing the neutralizing agent with the catalyst.
Claim 2
Independent Claim
64 words
A method of neutralizing the catalyst used in the alkaline polymerization of diorganocyclosiloxane in which the neutralizing agent is a composition of the formula R' 3 SiOC(O)R", where R' is a hydrocarbon radical of from 1 to 6 carbon atoms inclusive and R" is a hydrocarbon radical of from 1 to 8 carbon atoms inclusive which comprises admixing the neutralizing agent with the catalyst.
Claim 3
Independent Claim
111 words
A method of polymerizing diorganocyclosiloxane comprising (A) mixing a diorganocyclosiloxane of the formula (R 2 SiO) x where R is selected from the group consisting of methyl, ethyl, phenyl, vinyl, and 3,3,3-trifluoropropyl, and x is from 3 to 5 inclusive with a catalytic amount of an alkaline polymerization catalyst, B. polymerizing the mixture until the desired molecular weight of the resulting polydiorganosiloxane is reached, and then (C) neutralizing the catalyst with the necessary amount of a composition of the formula R' 3 SiOC(O)R" where R' is a hydrocarbon radical of from 1 to 6 carbon atoms inclusive and R" is a hydrocarbon radical of from 1 to 8 carbon atoms inclusive.
Claim 4
Independent Claim
111 words
A method of polymerizing diorganocyclosiloxane comprising (A) mixing a diorganocyclosiloxane of the formula (R 2 SiO) x where R is selected from the group consisting of methyl, ethyl, phenyl, vinyl, and 3,3,3-trifluoropropyl, and x is from 3 to 5 inclusive with a catalytic amount of an alkaline polymerization catalyst, B. polymerizing the mixture until the desired molecular weight of the resulting polydiorganosiloxane is reached, and then (C) neutralizing the catalyst with the necessary amount of a composition of the formula R' 3 SiOC(O)R" where R' is a hydrocarbon radical of from 1 to 6 carbon atoms inclusive and R" is a hydrocarbon radical of from 1 to 8 carbon atoms inclusive.
Claim 5
Dependent Claim
13 words
The method of claim 1 in which R' and R" are methyl radicals.
Claim 6
Independent Claim
82 words
A method of polymerizing diorganocyclosiloxane of the type in which diorganocyclosiloxane is mixed with a catalytic amount of an alkaline polymerization catalyst and polymerized until the desired molecular weight of the resulting polydiorganosiloxane is reached, whereinthe improvement comprises neutralizing the catalyst with the necessary amount of a composition of the formula R' 3 SiOC(O)R" where R' is a hydrocarbon radical of from 1 to 6 carbon atoms inclusive and R" is a hydrocarbon radical of from 1 to 8 carbon atoms inclusive.
Claim 7
Independent Claim
82 words
A method of polymerizing diorganocyclosiloxane of the type in which diorganocyclosiloxane is mixed with a catalytic amount of an alkaline polymerization catalyst and polymerized until the desired molecular weight of the resulting polydiorganosiloxane is reached, whereinthe improvement comprises neutralizing the catalyst with the necessary amount of a composition of the formula R' 3 SiOC(O)R" where R' is a hydrocarbon radical of from 1 to 6 carbon atoms inclusive and R" is a hydrocarbon radical of from 1 to 8 carbon atoms inclusive.
Claim 8
Dependent Claim
13 words
The method of claim 2 in which R' and R" are methyl radicals.
Claim 9
Dependent Claim
13 words
The method of claim 4 in which R' and R" are methyl radicals.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-01-11 | 1991-07-13 | 1992-01-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-01-11 | 1995-07-13 | 1996-01-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-01-11 | 1999-07-13 | 2000-01-12 | $7700.00 | Window Closed / Lapsed |