US3046245A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of crystalline polystyrene solutions
Assignee: Monsanto Chemicals Ltd
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Filing: 1957-01-15
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Granted: 1962-07-24
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Expires: 1977-01-15
Abstract
No abstract record available.
Inventors
- 👤 Roland J Kern
- 👤 Allen S Kenyon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 16:47
CPC Classifications
C; C08; C08J; C08J3/00; C08J3/02; C08J3/09; C08J3/091; C08J2325/00; C08J2325/02; C08J2325/04; C08J2325/06
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
92 words
THE METHOD OF PREPARING A SOLUTION OF AT LEAST ABOUT 2 WEIGHT PERCENT OF ISOTACTIC POLYSTYRENE, WHICH METHOD COMPRISES HEATING CRYSTALLINE POLYSTYRENE TO A TEMPERATURE ABOVE THE MELTING POINT OF THE CRYSTALLINE PORTION THEREOF AND BELOW THE DECOMPOSITION POINT OF THE POLYSTYRENE, COOLING SAID POLYSTYRENE TO A TEMPERATURE BELOW ABOUT 110*C. AT A RATE SUFFICIENTLY RAPID TO OBTAIN AN AMORPHOUS ISOTACTIC POLYSTYRENE HAVING LESS THAN ONE PERCENT CRYSTALLINITY, AND THEREAFTER DISSOLVING SAID POLYSRYRENE IN BETWEEN ABOUT 1 AND ABOUT 49 TIMES BY WEIGHT OF A SOLVENT WHICH WILL DISSOLVE CONVENTIONAL AMORPHOUS POLYSTYRENE.
Claim 2
Independent Claim
92 words
THE METHOD OF PREPARING A SOLUTION OF AT LEAST ABOUT 2 WEIGHT PERCENT OF ISOTACTIC POLYSTYRENE, WHICH METHOD COMPRISES HEATING CRYSTALLINE POLYSTYRENE TO A TEMPERATURE ABOVE THE MELTING POINT OF THE CRYSTALLINE PORTION THEREOF AND BELOW THE DECOMPOSITION POINT OF THE POLYSTYRENE, COOLING SAID POLYSTYRENE TO A TEMPERATURE BELOW ABOUT 110*C. AT A RATE SUFFICIENTLY RAPID TO OBTAIN AN AMORPHOUS ISOTACTIC POLYSTYRENE HAVING LESS THAN ONE PERCENT CRYSTALLINITY, AND THEREAFTER DISSOLVING SAID POLYSRYRENE IN BETWEEN ABOUT 1 AND ABOUT 49 TIMES BY WEIGHT OF A SOLVENT WHICH WILL DISSOLVE CONVENTIONAL AMORPHOUS POLYSTYRENE.
References Cited (Backward Citations)
CA503973A
Cited
US2581922A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1965-07-23 | 1966-01-22 | 1966-07-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1969-07-23 | 1970-01-22 | 1970-07-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1973-07-23 | 1974-01-22 | 1974-07-24 | $7700.00 | Window Closed / Lapsed |