Patent US3640913A successfully refreshed from Google Patents.
US3640913A
Expired / Lapsed
US
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Process for heating polymers with dielectric heating
Assignee: Dow Chemical Co
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Filing: 1969-04-17
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Granted: 1972-02-08
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Expires: 1989-04-17
Abstract
Abstract POLYMERS ARE RAPIDLY HEATED BY AN IMPROVED PROCESS WHEREIN (1) A COMPOSITION CONTAINING AN ORGANIC POLYMER IS BLENDED WITH A ZINC HALIDE AND (2) THE RESULTANT BLEND IS HEATED BY APPLYING TO IT A HIGH FREQUENCY ALTERNATING ELECTRIC FIELD. THE IMPROVED PROCESS IS PARTICULARLY USEFUL IN PREPARING FOAMED POLYMERS WHEREIN A CONVENTIONAL BLOWING AGENT IS INCORPORATED INTO A BLEND OF ORGANIC POLYMER AND ZINC HALIDE AND THE BLEND IS THEN DIELECTRICALLY HEATED.
Inventors
- 👤 Peter A Cerra
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:56
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/0066; C08K; C08K3/00; C08K3/16; Y; Y10; Y10S; Y10S521/00; Y10S521/915
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) | 1975-02-07 | 1975-08-09 | 1976-02-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-07 | 1979-08-09 | 1980-02-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-07 | 1983-08-09 | 1984-02-08 | $7700.00 | Window Closed / Lapsed |