Patent US3092407A successfully refreshed from Google Patents.
Patent US2687231A successfully refreshed from Google Patents.
Patent US2520733A successfully refreshed from Google Patents.
US2520733A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polymers of trimethylene glycol
Assignee: Shell Development Co
•
Filing: 1946-08-26
•
Granted: 1950-08-29
•
Expires: 1966-08-26
Abstract
No abstract record available.
Inventors
- 👤 Rupert C Morris
- 👤 Snider Alva Vance
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:13
CPC Classifications
C; C08; C08G; C08G65/00; C08G65/34; C10; C10M; C10M3/00; C10M2209/00; C10M2209/10; C10M2209/103; C10M2209/104; C10M2209/105; C10M2209/106; C10M2209/107; C10M2209/109; C10M2213/00; C10M2213/04; C10M2213/06; C10M2215/00; C10M2215/02; C10M2215/06; C10M2215/064; C10M2215/065; C10M2215/066; C10M2215/20; C10M2217/00; C10M2217/02; C10M2217/04; C10M2217/042; C10M2217/043; C10M2219/00; C10M2219/04; C10M2219/042; C10M2221/00; C10M2221/04; C10M2221/043; C10M2225/00; C10M2225/02; C10N; C10N2020/00; C10N2020/01; C10N2040/00; C10N2040/08; C10N2050/00; C10N2050/10
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
62 words
A PROCESS FOR THE PREPARATION OF POLYMERIC MATERIALS WHICH COMPRISES HEATING TRIMETHYLENE GLYCOL AT A TEMPERATURE FROM ABOUT 170*C. TO ABOUT 300*C. IN THE PRESENCE OF FROM 2.5% TO 6% BY WEIGHT OF SAID GLYCOL OF AN ACID-ACTING CATALYST, WHEREBY A MIXTURE OF POLYMERS OF SAID GLYCOL IS FORMED, SAID MIXTURE HAVING AN AVERAGE MOLECULAR WEIGHT FROM ABOUT 200 TO ABOUT 1500.
Claim 2
Dependent Claim
62 words
A PROCESS FOR THE PREPARATION OF POLYMERIC MATERIALS WHICH COMPRISES HEATING TRIMETHYLENE GLYCOL AT A TEMPERATURE FROM ABOUT 170*C. TO ABOUT 300*C. IN THE PRESENCE OF FROM 2.5% TO 6% BY WEIGHT OF SAID GLYCOL OF AN ACID-ACTING CATALYST, WHEREBY A MIXTURE OF POLYMERS OF SAID GLYCOL IS FORMED, SAID MIXTURE HAVING AN AVERAGE MOLECULAR WEIGHT FROM ABOUT 200 TO ABOUT 1500.
References Cited (Backward Citations)
US2253723A
Cited
US2355823A
Cited
US1930572A
Cited
DE566032C
Cited
US2069336A
Cited
US2043688A
Cited
US2120227A
Cited
US2411150A
Cited
US2383915A
Cited
US2383916A
Cited
US2366042A
Cited
US2425755A
Cited
US2425845A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-08-28 | 1954-02-27 | 1954-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-08-28 | 1958-02-27 | 1958-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-08-28 | 1962-02-27 | 1962-08-29 | $7700.00 | Window Closed / Lapsed |