Patent US3239490A successfully refreshed from Google Patents.
US3239490A
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Continuous anionic polymerisation of lactams
Assignee: Imperial Chemical Industries Ltd
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Filing: 1962-06-07
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Granted: 1966-03-08
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Expires: 1982-06-07
Abstract
No abstract record available.
Inventors
- 👤 Gee Kenneth Henry
- 👤 Small Percy Arthur
- 👤 Zichy Erno Laszlo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 20:59
CPC Classifications
C; C08; C08G; C08G69/00; C08G69/02; C08G69/08; C08G69/14; C08G69/16; C08G69/18
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
132 words
A CONTINUOUS PROCESS FOR THE PRODUCTION OF POLYAMIDES WHICH COMPRISES HEATING IN A FIRST ZONE A MIXTURE (1) CONTAINING AT LEAST ONE MONOMERIC LACTAM OF A NONOAMINO MONOCARBOXYLIC ACID, SAID LACTAM CONTAINING AT LEAST SIX CARBON ATOMS IN THE LACTAM RING, AN ALKALINE POLYMERISATION CATALYST AND A CATALYST PROMOTER, TO A TEMPERATURE ABOVE THE MELTING POINT OF THE POLYAMIDE, SAID MIXTURE (1), IN THE COURSE OF HEATING TO ELEVATED TEMPERATURES, UNDERGOING A REACTION IN WHICH THE VISCOSITY INCREASES TO A MAXIMUM AND THEN DECREASES ON CONTINUED HEATING, CONTINUALLY ADVANCING SAID MIXTURE (1) THROUGH SAID FIRST ZONE, THE RATE OF ADVANCEMENT OF THE MIXTURE BEING SUCH THAT, WHEN IT REACHES THE END OF SAID FIRST ZONE, IT BECOMES A MIXTURE (2), THE VISCOSITY (N) OF THE MIXTURE (2) BEING GIVEN BY THE FORMULA:
Claim 2
Dependent Claim
132 words
A CONTINUOUS PROCESS FOR THE PRODUCTION OF POLYAMIDES WHICH COMPRISES HEATING IN A FIRST ZONE A MIXTURE (1) CONTAINING AT LEAST ONE MONOMERIC LACTAM OF A NONOAMINO MONOCARBOXYLIC ACID, SAID LACTAM CONTAINING AT LEAST SIX CARBON ATOMS IN THE LACTAM RING, AN ALKALINE POLYMERISATION CATALYST AND A CATALYST PROMOTER, TO A TEMPERATURE ABOVE THE MELTING POINT OF THE POLYAMIDE, SAID MIXTURE (1), IN THE COURSE OF HEATING TO ELEVATED TEMPERATURES, UNDERGOING A REACTION IN WHICH THE VISCOSITY INCREASES TO A MAXIMUM AND THEN DECREASES ON CONTINUED HEATING, CONTINUALLY ADVANCING SAID MIXTURE (1) THROUGH SAID FIRST ZONE, THE RATE OF ADVANCEMENT OF THE MIXTURE BEING SUCH THAT, WHEN IT REACHES THE END OF SAID FIRST ZONE, IT BECOMES A MIXTURE (2), THE VISCOSITY (N) OF THE MIXTURE (2) BEING GIVEN BY THE FORMULA:
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-03-07 | 1969-09-06 | 1970-03-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-03-07 | 1973-09-06 | 1974-03-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-03-07 | 1977-09-06 | 1978-03-08 | $7700.00 | Window Closed / Lapsed |