US4163833A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for making aromatic cyclic polyformal
Assignee: General Electric Co
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Filing: 1978-05-15
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Granted: 1979-08-07
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Expires: 1998-05-15
Abstract
Abstract There is provided, a method for making cyclic poly-formal substantially free of linear polyformal by agitating a plural phase mixture of an aqueous alkali metal salt solution of bisphenol in contact with methylene halide and a phase transfer catalyst. The cyclic polyformal can be used to make wire coating compositions.
Inventors
- 👤 Donald S. Johnson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 04:46
CPC Classifications
C; C08; C08G; C08G65/00; C08G65/34; C08G65/38; C08G65/40; C08G65/4006; C08G4/00; C08G65/4081; C08G2650/00; C08G2650/28; C08G2650/38; C08G2650/44; C08G2650/46; C08G2650/48
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
142 words
A method for making aromatic cyclic polyformal which comprises (A) refluxing a plural phase mixture comprising (a) a bisphenol of the formula, HO--R--OH, (b) alkali metal hydroxide, (c) water, (d) methylene halide and (e) a phase transfer catalyst, where in the plural phase mixture, the concentration of bisphenol does not exceed 3% by weight of the aqueous phase, there is utilized per mole of the bisphenol, more than 2 moles of alkali metal hydroxide and more than 1 mole of methylene halide, and there is present by volume at least 0.5 part of organic phase, per part of aqueous phase, (B) recovering aromatic cyclic polyformal from the mixture of (A), by effecting the separation of the aromatic cyclic polyformal by the use of methanol or by effecting the evaporation of organic solvent therefrom, where R is selected from C.sub.(6-25) divalent aromatic radicals.
Claim 2
Independent Claim
142 words
A method for making aromatic cyclic polyformal which comprises (A) refluxing a plural phase mixture comprising (a) a bisphenol of the formula, HO--R--OH, (b) alkali metal hydroxide, (c) water, (d) methylene halide and (e) a phase transfer catalyst, where in the plural phase mixture, the concentration of bisphenol does not exceed 3% by weight of the aqueous phase, there is utilized per mole of the bisphenol, more than 2 moles of alkali metal hydroxide and more than 1 mole of methylene halide, and there is present by volume at least 0.5 part of organic phase, per part of aqueous phase, (B) recovering aromatic cyclic polyformal from the mixture of (A), by effecting the separation of the aromatic cyclic polyformal by the use of methanol or by effecting the evaporation of organic solvent therefrom, where R is selected from C.sub.(6-25) divalent aromatic radicals.
Claim 3
Dependent Claim
12 words
A method in accordance with claim 1, where the bisphenol is 2,2-bis(4-hydroxyphenyl)ethylene.
Claim 4
Dependent Claim
14 words
A method in accordance with claim 1, where the methylene halide is methylene chloride.
Claim 5
Dependent Claim
15 words
A method in accordance with claim 1, where the alkali metal hydroxide is sodium hydroxide.
Claim 6
Dependent Claim
12 words
A method in accordance with claim 1, where the bisphenol is 1,1-dichloro-2,2-(4-hydroxyphenyl)ethylene.
References Cited (Backward Citations)
US3069386A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-08-06 | 1983-02-05 | 1983-08-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-08-06 | 1987-02-05 | 1987-08-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-08-06 | 1991-02-05 | 1991-08-07 | $7700.00 | Window Closed / Lapsed |