US3635931A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polyisoprene from amylenes via n-amylene isomerization oxidative dehydrogenation extractive distillation and polymerization of low-concentration isoprene
Assignee: Phillips Petroleum Co
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Filing: 1969-12-22
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Granted: 1972-01-18
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Expires: 1989-12-22
Abstract
Abstract A PROCESS FOR THE PRODUCTION OF POLYISPRENE FROM A RELATIVELY LOW-CONCENTRATION ISOPRENE STREAM OBTAINED FROM A FEEDSTOCK OF MIXED AMYLENES. ISOAMYLENES ARE SEPARATED FROM AN-AMYLENES BY MOLECULARE SIEVES, ISOAMYLENES IN PART DEHYDROGENATED TO ISOPRENE, CATALYST POISONS REMOVED BY EXTRACTIVE DISTILLATION, AND THE ISOPRENE CONTAINED IN THE STREAM THEN POLYMERIZED TO SYNTHETIC RUBBER. THE N-AMYLENES SEPARATED BY USE OF THE MOLECULAR SIEVES ARE SKELETALLY ISOMERIZED TO ISOAMYLENES AND RECYCLED TO THE MOLECULAR SIEVE SEPARATION.
Inventors
- 👤 Joseph W Davison
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:05
CPC Classifications
C; C08; C08F; C08F36/00; C08F36/02; C08F36/04; C07; C07C; C07C7/00; C07C7/12; C07C7/13
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) | 1975-01-17 | 1975-07-19 | 1976-01-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-17 | 1979-07-19 | 1980-01-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-17 | 1983-07-19 | 1984-01-18 | $7700.00 | Window Closed / Lapsed |