Patent US2833318A successfully refreshed from Google Patents.
Patent US2601673A successfully refreshed from Google Patents.
US2601673A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Shortstopping the addition polymerization of unsaturated organic compounds
Assignee: Shell Development Co
•
Filing: 1951-04-09
•
Granted: 1952-06-24
•
Expires: 1971-04-09
Abstract
No abstract record available.
Inventors
- 👤 Frank M Mcmillan
- 👤 Eugene T Bishop
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 05:16
CPC Classifications
C; C08; C08F; C08F2/00; C08F2/12; C08F2/16; C08F36/00; C08F36/02; C08F36/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
67 words
IN THE POLYMERIZATION OF STYRENE IN THE FORM OF AN AQUEOUS EMULSION, THE STEP OF ADDING TO THE EMULSION AND IN THE PRESENCE OF A PEROXYGEN POLYMERIZATION CATALYST 0.001 TO 2 PARTS BY WEIGHT OF 2,2,4,6 - TETRAMETHYLDIHYDROPYRIDINE PER 100 PARTS BY WEIGHT OF STYRENE ORIGINALLY PRESENT IN THE EMULSION AFTER POLYMERIZATION OF STYRENE IN THE EMULSION OT POLYSTYRENE AND WHILE SAID EMULSION STILL CONTAINS UNCOVERTED STYRENE.
Claim 2
Dependent Claim
67 words
IN THE POLYMERIZATION OF STYRENE IN THE FORM OF AN AQUEOUS EMULSION, THE STEP OF ADDING TO THE EMULSION AND IN THE PRESENCE OF A PEROXYGEN POLYMERIZATION CATALYST 0.001 TO 2 PARTS BY WEIGHT OF 2,2,4,6 - TETRAMETHYLDIHYDROPYRIDINE PER 100 PARTS BY WEIGHT OF STYRENE ORIGINALLY PRESENT IN THE EMULSION AFTER POLYMERIZATION OF STYRENE IN THE EMULSION OT POLYSTYRENE AND WHILE SAID EMULSION STILL CONTAINS UNCOVERTED STYRENE.
References Cited (Backward Citations)
US2516625A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-06-24 | 1955-12-24 | 1956-06-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-06-24 | 1959-12-24 | 1960-06-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-06-24 | 1963-12-24 | 1964-06-24 | $7700.00 | Window Closed / Lapsed |