US2500149A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sulfonation of copolymers of monovinyl-and polyvinyl-aromatic compounds
Assignee: Dow Chemical Co
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Filing: 1947-02-21
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Granted: 1950-03-14
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Expires: 1967-02-21
Abstract
No abstract record available.
Inventors
- 👤 Raymond F Boyer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 21:47
CPC Classifications
B; B01; B01J; B01J39/00; B01J39/08; B01J39/16; B01J39/18; B01J39/20; C; C08; C08F; C08F8/00; C08F8/34; C08F8/36; B29; B29B; B29B9/00; B29B9/12; B29B9/16; C08F2800/00; C08F2800/20
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
74 words
IN A METHOD WHEREIN A BENZENE-SWELLABLE COPOLYMER OF AT LEAST ONE MONOVINYL-AROMATIC COMPOUND, OF THE CLASS CONSISTING OF MONOVINYL-AROMATIC HYDROCARBONS AND AR-MONOCHLORO-MONOVINYL-AROMATIC HYDROCARBONS, AND FROM 3 TO 20 PER CENT BY WEIGHT OF A POLYVINYL-AROMATIC HYDROCARBON IS SULPHONATED BY REACTION WITH A SULPHONATING AGENT, THE IMPROVEMENT WHICH CONSISTS IN SWELLING THE COPOLYMER BY CONTACTING THE SAME WITH AN ORGANIC LIQUID CAPABLE OF SWELLING POLYSTYRENE AND THEREAFTER REACTING THE SWOLLEN COPOLYMER WITH THE SULPHONATING AGENT.
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) | 1953-03-13 | 1953-09-12 | 1954-03-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-03-13 | 1957-09-12 | 1958-03-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-03-13 | 1961-09-12 | 1962-03-14 | $7700.00 | Window Closed / Lapsed |