US3789054A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing polyphenylene ethers
Assignee: Asahi Kasei Corp
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Filing: 1971-12-06
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Granted: 1974-01-29
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Expires: 1991-12-06
Abstract
Abstract Polyphenylene ethers of 5 microns or more in particle size which are useful for preparation of parts of electric devices are continuously produced according to oxidative polymerization of 2,6-disubstituted phenols by preparing a 15 to 35 % (by weight) solution of 2,6-disubstituted phenol in dimethylformamide or in a mixed solvent composed of toluene and methanol, subjecting the solution to polymerization in one zone while maintaining the reaction system in the state of a homogeneous solution, and transferring the polymerization liquid to another zone to complete the polymerization while allowing the resulting polymer to precipitate.
Inventors
- 👤 S Izawa
- 👤 K Toyama
- 👤 H Okamoto
- 👤 Y Sugawara
- 👤 T Tanaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 15:06
CPC Classifications
C; C08; C08G; C08G65/00; C08G65/34; C08G65/38; C08G65/44; C08F; C08F12/00; C08F12/02; C08F12/04; C08F283/00; C08F283/06; C08F283/08
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
14 words
A process according to claim 1 wherein the 2,6-disubstituted phenol is 2,6-dimethylphenol or 2,6-diethylphenol.
Claim 2
Dependent Claim
35 words
A process according to claim 1, wherein the medium is one member selected from the group consisting of dimethylformamide, dimethylacetamide, trimethylene glycol, hexamethylene glycol, dimethyl sulfoxide, hexamethyl phosphotriamide, methylethylketone, diethylketone, acetylacetone, benzylmethylketone and diethyl carbonate.
Claim 3
Dependent Claim
102 words
A process according to claim 1, wherein the medium is a mixture of at least one member selected from the group consisting of benzene, toluene, xylene, chlorobenzene, dichlorobenzene, nitrobenzene, ethylbenzene, styrene, methylstyrene, chlorostyrene, dimethylstyrene, methylene dichloride, chloroform, dichloroethylene, trichloroethylene, bromoform, benzonitrile, furan, thiophene, cyclopentanone and cyclohexanone, with at least one member selected from the group consisting of methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, tert-butanol, n-hexanol, n-heptanol, benzyl alcohol, cyclopentanol, cyclohexanol, water, acetonitrile, propionitrile, acrylonitrile, diethyl ether, tetrahydrofuran, pentane, n-hexane, 2-methylpentane, n-heptane, n-octane, iso-octane, cyclopentane, cyclohexane, dimethylformamide, dimethylacetamide, trimethylene glycol, hexamethylene glycol, dimethyl sulfoxide, hexamethyl phosphotriamide, methylethylketone, diethylketone, acetyLacetone, benzylmethylketone and diethyl carbonate.
Claim 4
Dependent Claim
22 words
A process according to claim 1, wherein the reaction temperatures in both the first and second steps are individually 20* to 70*C.
Claim 5
Dependent Claim
25 words
A process according to claim 1, wherein the average staying times in both the first and second steps are individually 15 minutes to 7 hours.
Claim 6
Dependent Claim
25 words
A process according to claim 1, wherein the average staying times in both the first and second steps are individually 30 minutes to 4 hours.
Claim 7
Dependent Claim
23 words
A process according to claim 1, wherein the first step is carried out while removing the heat of polymerization as much as possible.
Claim 8
Dependent Claim
19 words
A process according to claim 1, wherein the reaction liquid is further subjected to a third step for aging.
Claim 9
Dependent Claim
16 words
A process according to claim 1, wherein each step is subdivided into two or more steps.
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) | 1977-01-28 | 1977-07-30 | 1978-01-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-28 | 1981-07-30 | 1982-01-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-28 | 1985-07-30 | 1986-01-29 | $7700.00 | Window Closed / Lapsed |