Patent US4348532A successfully refreshed from Google Patents.
US4348532A
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Monoorganosiloxy containing siloxane fluids
Assignee: Dow Silicones Corp
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Filing: 1981-10-05
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Granted: 1982-09-07
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Expires: 2001-10-05
Abstract
Abstract Organosiloxane fluids containing polyfunctional silicon atoms are made by reacting a mixture of chlorosilanes containing a silane or disilane having at least 3 chlorine atoms with methanol in contact with certain quaternary ammonium halide catalysts. For example a fluid methylpolysiloxane was obtained by reacting a mixture of 30 weight percent methyltrichlorosilane and 70 weight percent dimethyldichlorosilane with methanol in contact with methyl pyridinium chloride.
Inventors
- 👤 Allan M. Alanko
- 👤 Ollie W. Marko
- 👤 Charles E. Skinner
- 👤 Larry H. Wood
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 15:01
CPC Classifications
C; C08; C08G; C08G77/00; C08G77/04; C08G77/06; C08G77/08; C07; C07C; C07C17/00; C07C17/093; C07C17/16
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
260 words
In a method for preparing siloxanes and methyl chloride by reacting methanol with chlorosilanes in contact with a quaternary ammonium catalyst of the group consisting of: (1) pyridinium chlorides of the formula ##STR3## (2) compounds of the formula R'" 4 N + Cl - , ##STR4## where R' is a hydrocarbon radical having 18 or less carbon atoms; "a" is an integer from 0-5; "m" is an integer greater than 1, R" is a lower alkyl radical; and R'" is selected from the group consisting of methyl, hydroxy alkyl of 2-4 inclusive carbon atoms, aromatic hydrocarbon radicals, and ArCH 2 -- radicals in which Ar is an aromatic hydrocarbon radical there being no more than 18 carbon atoms total in the R'" group, the improvement comprising employing as the chlorosilanes a mixture of R 2 SiCl 2 and a silane (A) selected from the group consisting of RSiCl 3 and R n Cl 3-n SiSiR n' Cl 3-n' and optionally R 3 SiCl in which mixture there is from 2 to 50 percent by weight based upon the total weight of the chlorosilane mixture of a silane containing at least 3 chlorine atoms per molecule, said reaction being carried out at a temperature of at least about 100° C. and under temperature/pressure relationship such that water escapes from the reaction zone, whereby stable polysiloxane fluids are obtained, in said silanes R is methyl, ethyl, 3-chloropropyl, or 3,3,3-trifluoropropyl and n and n' are each integers from 0 to 2, the total value of n and n' being from 1 to 3.
Claim 2
Dependent Claim
260 words
In a method for preparing siloxanes and methyl chloride by reacting methanol with chlorosilanes in contact with a quaternary ammonium catalyst of the group consisting of: (1) pyridinium chlorides of the formula ##STR3## (2) compounds of the formula R'" 4 N + Cl - , ##STR4## where R' is a hydrocarbon radical having 18 or less carbon atoms; "a" is an integer from 0-5; "m" is an integer greater than 1, R" is a lower alkyl radical; and R'" is selected from the group consisting of methyl, hydroxy alkyl of 2-4 inclusive carbon atoms, aromatic hydrocarbon radicals, and ArCH 2 -- radicals in which Ar is an aromatic hydrocarbon radical there being no more than 18 carbon atoms total in the R'" group, the improvement comprising employing as the chlorosilanes a mixture of R 2 SiCl 2 and a silane (A) selected from the group consisting of RSiCl 3 and R n Cl 3-n SiSiR n' Cl 3-n' and optionally R 3 SiCl in which mixture there is from 2 to 50 percent by weight based upon the total weight of the chlorosilane mixture of a silane containing at least 3 chlorine atoms per molecule, said reaction being carried out at a temperature of at least about 100° C. and under temperature/pressure relationship such that water escapes from the reaction zone, whereby stable polysiloxane fluids are obtained, in said silanes R is methyl, ethyl, 3-chloropropyl, or 3,3,3-trifluoropropyl and n and n' are each integers from 0 to 2, the total value of n and n' being from 1 to 3.
Claim 3
Dependent Claim
18 words
The method of claim 1 in which the chlorosilane mixture and methanol are passed through a molten catalyst.
Claim 4
Dependent Claim
10 words
The method of claim 1 in which R is methyl.
Claim 5
Dependent Claim
10 words
The method of claim 2 in which R is methyl.
Claim 6
Dependent Claim
19 words
The method of claim 1 or 2 in which (A) is methyltrichlorosilane and the catalyst is methyl pyridinium chloride.
References Cited (Backward Citations)
US4108882A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-09-06 | 1986-03-08 | 1986-09-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-09-06 | 1990-03-08 | 1990-09-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-09-06 | 1994-03-08 | 1994-09-07 | $7700.00 | Window Closed / Lapsed |