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US3749693A
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US
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Process for the preparation of polyphenylene ethers and compositions containing the same
Assignee: General Electric Co
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Filing: 1971-11-05
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Granted: 1973-07-31
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Expires: 1991-11-05
Abstract
Abstract A PROCESS FOR THE PREPARATION OF 2,6-DISUBSTITUTED-1,2PHENYLENE ETHER DIMERS, OLIGOMERS AND POLYMERS, SUCH AS THOSE OF THE FORMULA: (2-Q,6-Q'',4-CH3-PHENYL)-O-((3-Q,5-Q''-1,4-PHENYLENE)-O)N-H WHEREIN Q AND Q'' ARE SELECTED FROM THE GROUP CONSISTING OF LOWER ALIPHATIC RADICALS HAVING FROM 1-4 CARBON ATOMS AND PHENYL; AND N IS A WHOLE INTEGER OF FROM 1 TO ABOUT 300, WHICH COMPRISES POLYMERIZING A SUITABLE MONOMER IN THE PRESENCE OF OXYGEN AND A COPPER-AMINE CATALYST, THE HIGH MOLECULAR WEIGHT PRODUCTS ARE ENGINEERING THERMOPLASTICS, AND THE LOW MOLECULAR WEIGHT PRODUCTS ARE OXIDATION STABILIZERS AND MELT VISCOSITY IMPROVES FOR THERMOPLASTICS.
Inventors
- 👤 G Cooper
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 18:05
CPC Classifications
C; C08; C08L; C08L71/00; C08L71/08; C08L71/10; C08L71/12; C08L71/123; C08G; C08G65/00; C08G65/34; C08G65/38; C08G65/44
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-30 | 1977-01-29 | 1977-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-30 | 1981-01-29 | 1981-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-30 | 1985-01-29 | 1985-07-31 | $7700.00 | Window Closed / Lapsed |