US2835658A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparing polystyrene block polymers
Assignee: Dow Chemical Co
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Filing: 1957-03-01
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Granted: 1958-05-20
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Expires: 1977-03-01
Abstract
No abstract record available.
Inventors
- 👤 John L Lang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 22:09
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/91; C08F; C08F212/00; C08F212/02; C08F212/04; C08F212/06; C08F212/08
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
34 words
A PROCESS FOR PREPARING POLYSTRENE BLOCK POLYMERS HAVING SPECIFIC END GROUPS CONSISTIONG OF SEQUENTIALLY SUBJECTING A MIXTURE OF STYRENE AND BETA-PROPIOLACTONE TO A FREE-RADICAL BULK POLYMERIZATION AND HYDROLYZING THE SO FORMED POLYMER WITH WATER.
Claim 2
Dependent Claim
34 words
A PROCESS FOR PREPARING POLYSTRENE BLOCK POLYMERS HAVING SPECIFIC END GROUPS CONSISTIONG OF SEQUENTIALLY SUBJECTING A MIXTURE OF STYRENE AND BETA-PROPIOLACTONE TO A FREE-RADICAL BULK POLYMERIZATION AND HYDROLYZING THE SO FORMED POLYMER WITH WATER.
Claim 3
Dependent Claim
82 words
A PROCESS FOR PREPARING POLYSTYRENE BLOCK POLYMERS HAVING THE SAME SPECIFIC END GROUPS CONSISTING OF SEQUENTIALLY SUBJECTING A MIXTURE OF STYRENE AND BETAPROPIOLACTONE TO A FREE RADICAL POLYMERIZATION, HYDROLYZING THE SO-FORMED POLYMER WITH WATER AND BRINGING THE SO-FORMED BLOCKS INTO REACTIVE CONTACT WITH A POLYFUNCTIONAL COMPOUND CAPABLE OF REACTING WITH A GROUP SELECTED FROM HYDROXYL AND CARBOXYL WITH ONLY ONE TYPE OF FUNCTIONAL GROUP PRESENT IN THE HYDROLYZED PRODUCT, TO FORM A COMPOUND OF THE CLASS CONSISTING OF POLYESTERPOLYACIDS, POLYESTERPOLYALCOHOLS, AND POLYAMINDEPOLYALCOHOLS.
Claim 4
Dependent Claim
82 words
A PROCESS FOR PREPARING POLYSTYRENE BLOCK POLYMERS HAVING THE SAME SPECIFIC END GROUPS CONSISTING OF SEQUENTIALLY SUBJECTING A MIXTURE OF STYRENE AND BETAPROPIOLACTONE TO A FREE RADICAL POLYMERIZATION, HYDROLYZING THE SO-FORMED POLYMER WITH WATER AND BRINGING THE SO-FORMED BLOCKS INTO REACTIVE CONTACT WITH A POLYFUNCTIONAL COMPOUND CAPABLE OF REACTING WITH A GROUP SELECTED FROM HYDROXYL AND CARBOXYL WITH ONLY ONE TYPE OF FUNCTIONAL GROUP PRESENT IN THE HYDROLYZED PRODUCT, TO FORM A COMPOUND OF THE CLASS CONSISTING OF POLYESTERPOLYACIDS, POLYESTERPOLYALCOHOLS, AND POLYAMINDEPOLYALCOHOLS.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-05-19 | 1961-11-18 | 1962-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-05-19 | 1965-11-18 | 1966-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-05-19 | 1969-11-18 | 1970-05-20 | $7700.00 | Window Closed / Lapsed |