Patent US2283924A successfully refreshed from Google Patents.
US2809958A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polymerization procedures for 2-pyrrolidone
Assignee: GAF Chemicals Corp
•
Filing: 1953-02-24
•
Granted: 1957-10-15
•
Expires: 1973-02-24
Abstract
No abstract record available.
Inventors
- 👤 Carl E Barnes
- 👤 Jr William O Ney
- 👤 William R Nummy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 17:34
CPC Classifications
C; C08; C08G; C08G69/00; C08G69/02; C08G69/08; C08G69/14; C08G69/24
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
109 words
IN THE POLYMERIZATION OF 2-PYRROLIDONE USING A POLYMERIZATION CATALYST SELECTED FROM THE GROUP CONSISTING OF ALKALI METALS, THEIR SALTS, HYDROXIDES, OXIDES AND AMIDES, ALKALINE EARTH METALS AND HYDROXIDES AND STRONGLY BASIC ORGANIC METALLIC COMPOUNDS, THE IMPROVEMENT WHICH COMPRISES EFFECTING POLYMERIZATION IN THE PRESENCE OF AN ACYL ACTIVATOR EACH ACYL RADICAL OF WHICH IS AN ACYL RADICAL OF A CARBOXYLIC ACID AND SELECTED FROM THE GROUP CONSISTING OF ORGANIC ACYL PEROXIDES AND CARBOXYLIC ACID ANHYDRIDES, LACTONES, LACTIDES, N-ACYL DERIVATIVES OF LACTAMS, ACYL HALIDES AND ALCOHOL ESTERES OF CARBOXYLIC ACIDS AND WHEREIN THE CONCENTRATION OF SAID ACYL ACTIVATOR IS BETWEEN 0.001% AND 25% OF THE WEIGHT OF SAID PYRROLIDONE BEING POLYMERIZED.
Claim 2
Dependent Claim
109 words
IN THE POLYMERIZATION OF 2-PYRROLIDONE USING A POLYMERIZATION CATALYST SELECTED FROM THE GROUP CONSISTING OF ALKALI METALS, THEIR SALTS, HYDROXIDES, OXIDES AND AMIDES, ALKALINE EARTH METALS AND HYDROXIDES AND STRONGLY BASIC ORGANIC METALLIC COMPOUNDS, THE IMPROVEMENT WHICH COMPRISES EFFECTING POLYMERIZATION IN THE PRESENCE OF AN ACYL ACTIVATOR EACH ACYL RADICAL OF WHICH IS AN ACYL RADICAL OF A CARBOXYLIC ACID AND SELECTED FROM THE GROUP CONSISTING OF ORGANIC ACYL PEROXIDES AND CARBOXYLIC ACID ANHYDRIDES, LACTONES, LACTIDES, N-ACYL DERIVATIVES OF LACTAMS, ACYL HALIDES AND ALCOHOL ESTERES OF CARBOXYLIC ACIDS AND WHEREIN THE CONCENTRATION OF SAID ACYL ACTIVATOR IS BETWEEN 0.001% AND 25% OF THE WEIGHT OF SAID PYRROLIDONE BEING POLYMERIZED.
References Cited (Backward Citations)
US2251519A
Cited
US2638463A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-10-14 | 1961-04-15 | 1961-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-10-14 | 1965-04-15 | 1965-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-10-14 | 1969-04-15 | 1969-10-15 | $7700.00 | Window Closed / Lapsed |