US3595840A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Control of particle size in vinyl monomer polymerization
Assignee: Phillips Petroleum Co
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Filing: 1968-11-25
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Granted: 1971-07-27
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Expires: 1988-11-25
Abstract
Abstract A PORTION OF THE POLYMER PARTICLES WITHDRAWN FROM A VAPOR PHASE POLYMERIZATION REACTOR ARE GROUND TO PRODUCE SEED POLYMER PARTICLES WHICH ARE THEN IMPREGNATED WITH A CATALYST AND REINTRODUCED INTO THE POLYMERIZATION REACTOR. THE PORTION TO BE GROUND CAN BE THE PARTICLES HAVING A PARTICLE SIZE GREATER THAN A DESIRED VALUE WHICH ARE OBTAINED BY SCREENING THE REACTOR EFFLUENT. POLYMER PARTICLES BELOW A MINIMUM SIZE CAN ALSO BE RETURNED TO THE REACTOR. STABILIZERS CAN BE ADDED TO THE REACTOR TO IMPROVED THE PROPERTIES OF THE POLYMER.
Inventors
- 👤 Charles W Moberly
- 👤 Gerald R Kahle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 23:50
CPC Classifications
C; C08; C08F; C08F291/00; Y; Y10; Y10S; Y10S526/00; Y10S526/909; Y10S526/913
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) | 1974-07-26 | 1975-01-25 | 1975-07-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-26 | 1979-01-25 | 1979-07-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-26 | 1983-01-25 | 1983-07-27 | $7700.00 | Window Closed / Lapsed |