US2896264A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making shaped articles of crystalline polystyrene
Assignee: Montedison SpA
•
Filing: 1957-11-05
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Granted: 1959-07-28
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Expires: 1977-11-05
Abstract
No abstract record available.
Inventors
- 👤 Natta Giulio
- 👤 Crespi Giovanni
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:57
CPC Classifications
C; C08; C08J; C08J7/00; C08J7/08; B; B29; B29B; B29B13/00; C08J5/00; C08J2325/00; C08J2325/02; C08J2325/04; C08J2325/06; Y; Y10; Y10S; Y10S264/00; Y10S264/64; Y10S8/00; Y10S8/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
122 words
A METHOD FOR MAKING SHAPED ARTICULES OF CRYSTALLINE, LINER HIGHER POLYMERS OF STYRENE FROM POLYSYRENES CONSISTING ESSENTIALLY OF A MIXTURE OF NON-CRYSTALLIZAVBLE, ATACTIC POLYMERS, BLOCK POLYMERS, ANS CRYSTALLIZABLE, ISOTACTIC POLYMERS OF STYRENE, WHICH COMPRISES SEPARATING AT LEAST THE NON-CRYSTASLLIZABLE ATACTIC POLYMER FROM THE MIXTURE OF POLYSTYRENES BY EXTRACTION WITH A SELECTIVE SOLVENT THEREFOR, AT A TEMPERATURE BELOW THE MELTING POINT OF THE CRYSTALLIZABLE, POLYMERS, SHAPING THE RESIDUE OF SUCH EXTRACTION AT A TEMPERATURE ABOVE THE MELTING POINT OF THE CRYSTALIZABLE, ISOTATIC PLYMERS TO OBTAINED A PREFORMED, ANNEALING THE PRE-FORMED AT A TEMPERATURE BELOW THE MELTING POINT TO EFFECT CRYSTALLIZATION OF THE CRYSTALLIZABLE, ISOTATIC POLYSTYRENE, AND THEN FINALLY SHAPING THE ANNEALED PRE-FORM AT A TEMPERATURE BELOW THE MELTING POINT OF THE CRYSTALLINE POLYSTYRENE.
Claim 2
Independent Claim
122 words
A METHOD FOR MAKING SHAPED ARTICULES OF CRYSTALLINE, LINER HIGHER POLYMERS OF STYRENE FROM POLYSYRENES CONSISTING ESSENTIALLY OF A MIXTURE OF NON-CRYSTALLIZAVBLE, ATACTIC POLYMERS, BLOCK POLYMERS, ANS CRYSTALLIZABLE, ISOTACTIC POLYMERS OF STYRENE, WHICH COMPRISES SEPARATING AT LEAST THE NON-CRYSTASLLIZABLE ATACTIC POLYMER FROM THE MIXTURE OF POLYSTYRENES BY EXTRACTION WITH A SELECTIVE SOLVENT THEREFOR, AT A TEMPERATURE BELOW THE MELTING POINT OF THE CRYSTALLIZABLE, POLYMERS, SHAPING THE RESIDUE OF SUCH EXTRACTION AT A TEMPERATURE ABOVE THE MELTING POINT OF THE CRYSTALIZABLE, ISOTATIC PLYMERS TO OBTAINED A PREFORMED, ANNEALING THE PRE-FORMED AT A TEMPERATURE BELOW THE MELTING POINT TO EFFECT CRYSTALLIZATION OF THE CRYSTALLIZABLE, ISOTATIC POLYSTYRENE, AND THEN FINALLY SHAPING THE ANNEALED PRE-FORM AT A TEMPERATURE BELOW THE MELTING POINT OF THE CRYSTALLINE POLYSTYRENE.
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) | 1962-07-27 | 1963-01-26 | 1963-07-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-07-27 | 1967-01-26 | 1967-07-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-07-27 | 1971-01-26 | 1971-07-28 | $7700.00 | Window Closed / Lapsed |