US2921932A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High pressure polymerization of styrene
Assignee: Monsanto Chemicals Ltd
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Filing: 1954-01-28
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Granted: 1960-01-19
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Expires: 1974-01-28
Abstract
No abstract record available.
Inventors
- 👤 Lowell E Erbaugh
- 👤 John D Calfee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 07:58
CPC Classifications
C; C08; C08F; C08F12/00; C08F12/02; C08F12/04; C08F12/06; C08F12/08
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
101 words
A PROCESS WHICH COMPRISES SUBJECTING A MONOMERIC MATERIAL COMPRISING AT LEAST A MAJOR PROPORTION OF STYRENE AND NOT MORE THAN A MINOR PROPORTION OF AT LEAST ONE ETHYLENICALLY UNSATURATED MONOMER COPOLYMERIZABLE THEREWITH TO POLYMERIZATION AT A PRESSURE OF AT LEAST 10,000 POUNDS PER SQUARE INCH, FIRST AT A TEMPERATURE WITHIN THE RANGE OF 90 TO 160*C. UNTIL AT LEAST 90% OF SAID MONOMERIC MATERIAL HAS BECOME POLYMERIZED AND THEN AT A TEMPERATURE ABOVE 170*C. UNTIL THE UNREACTED MONOMER CONTENT OF THE RESULTING REACTION PRODUCT IS LESS THAN 1.5 WEIGHT PERCENT, RESULTING IN THE PRODUCTION OF HIGH MOLECULAR WEIGHT RESINOUS STYRENE POLYMER.
Claim 2
Dependent Claim
101 words
A PROCESS WHICH COMPRISES SUBJECTING A MONOMERIC MATERIAL COMPRISING AT LEAST A MAJOR PROPORTION OF STYRENE AND NOT MORE THAN A MINOR PROPORTION OF AT LEAST ONE ETHYLENICALLY UNSATURATED MONOMER COPOLYMERIZABLE THEREWITH TO POLYMERIZATION AT A PRESSURE OF AT LEAST 10,000 POUNDS PER SQUARE INCH, FIRST AT A TEMPERATURE WITHIN THE RANGE OF 90 TO 160*C. UNTIL AT LEAST 90% OF SAID MONOMERIC MATERIAL HAS BECOME POLYMERIZED AND THEN AT A TEMPERATURE ABOVE 170*C. UNTIL THE UNREACTED MONOMER CONTENT OF THE RESULTING REACTION PRODUCT IS LESS THAN 1.5 WEIGHT PERCENT, RESULTING IN THE PRODUCTION OF HIGH MOLECULAR WEIGHT RESINOUS STYRENE POLYMER.
References Cited (Backward Citations)
US2685575A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-01-18 | 1963-07-20 | 1964-01-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-01-18 | 1967-07-20 | 1968-01-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-01-18 | 1971-07-20 | 1972-01-19 | $7700.00 | Window Closed / Lapsed |