Patent US2943987A successfully refreshed from Google Patents.
US2943987A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low pressure polymerization of dienes
Assignee: Shell USA Inc
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Filing: 1958-02-25
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Granted: 1960-07-05
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Expires: 1978-02-25
Abstract
No abstract record available.
Inventors
- 👤 William S Anderson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 17:00
CPC Classifications
C; C08; C08F; C08F36/00; C08F36/02; C08F36/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
63 words
THE PROCESS COMPRISING POLYMERIZING A CONJUGATED DIENE IN THE PRESENCE OF A CATALYST COMPOSITION COMPRISING FREE MERCURY AND A HEAVY METAL SALT SELECTED FROM THE GROUP CONSISTING OF HALIDES, NITRATES AND SULFATES, THE POLYMERIZATION BEING CONDUCTED BY EXPOSING THE REACTION MIXTURE TO A MERCURY LIGHT SOURCE, AND RECOVERING A POLYMER CONTAINING A MAJOR PORTION OF THE CIS 1,4-ADDITION PRODUCT OF THE CONJUGATED DIENE.
Claim 2
Dependent Claim
63 words
THE PROCESS COMPRISING POLYMERIZING A CONJUGATED DIENE IN THE PRESENCE OF A CATALYST COMPOSITION COMPRISING FREE MERCURY AND A HEAVY METAL SALT SELECTED FROM THE GROUP CONSISTING OF HALIDES, NITRATES AND SULFATES, THE POLYMERIZATION BEING CONDUCTED BY EXPOSING THE REACTION MIXTURE TO A MERCURY LIGHT SOURCE, AND RECOVERING A POLYMER CONTAINING A MAJOR PORTION OF THE CIS 1,4-ADDITION PRODUCT OF THE CONJUGATED DIENE.
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) | 1963-07-05 | 1964-01-04 | 1964-07-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-07-05 | 1968-01-04 | 1968-07-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-07-05 | 1972-01-04 | 1972-07-05 | $7700.00 | Window Closed / Lapsed |