Patent US3883469A successfully refreshed from Google Patents.
US3883469A
Expired / Lapsed
US
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Process for the production of polyamide mouldings
Assignee: Bayer AG
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Filing: 1974-04-10
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Granted: 1975-05-13
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Expires: 1994-04-10
Abstract
Abstract An improved process for the activated anionic polymerisation of lactams having at least 5 ring members, the improvement comprising polymerising the lactam in the presence of at least one silicate of sheet structure.
Inventors
- 👤 Bert Brassat
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 12:39
CPC Classifications
C; C08; C08G; C08G69/00; C08G69/02; C08G69/08; C08G69/14; C08G69/16; C08G69/18
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
59 words
IN THE PROCESS FOR THE PRODUCTION OF POLYAMIDES WITH REDUCED RESIDUAL MONOMER CONTENT BY ACTIVATED ANIONIC POLYMERIZATION OF LACTAMS HAVING AT LEAST 5 RING MEMBERS, THE IMPROVEMENT WHICH COMPRISES POLYYMERIZING SAID LACTAM IN THE PRESENCE OF 0.5 TO 25% BY WEIGHT BASED ON THE LACTAM OF AT LEAST ONE SILICATE SELECTED FROM THE GROUP OF SILICATES HAVING SHEET STRUCTURE.
Claim 2
Dependent Claim
59 words
IN THE PROCESS FOR THE PRODUCTION OF POLYAMIDES WITH REDUCED RESIDUAL MONOMER CONTENT BY ACTIVATED ANIONIC POLYMERIZATION OF LACTAMS HAVING AT LEAST 5 RING MEMBERS, THE IMPROVEMENT WHICH COMPRISES POLYYMERIZING SAID LACTAM IN THE PRESENCE OF 0.5 TO 25% BY WEIGHT BASED ON THE LACTAM OF AT LEAST ONE SILICATE SELECTED FROM THE GROUP OF SILICATES HAVING SHEET STRUCTURE.
Claim 3
Dependent Claim
30 words
An improved process as claimed in claim 1 wherein a mineral of the talc pyrophyllite group, kaolin allophane group, mica group, a serpentine mineral or a chlorite mineral is used.
Claim 4
Dependent Claim
83 words
In the process for the production of polyamides with reduced residual monomer content by activated anionic polymerization of lactams having at least 5 ring members, the improvement which comprises polymerizing said lactam in the presence of 0.5 to 25% by weight based on the lactam of at least one silicate selected from the group of silicates having sheet structure, the reduction in monomer content being at least 30% when compared with the same polymerization process wherein no silicate having sheet structure is employed.
Claim 5
Dependent Claim
83 words
In the process for the production of polyamides with reduced residual monomer content by activated anionic polymerization of lactams having at least 5 ring members, the improvement which comprises polymerizing said lactam in the presence of 0.5 to 25% by weight based on the lactam of at least one silicate selected from the group of silicates having sheet structure, the reduction in monomer content being at least 30% when compared with the same polymerization process wherein no silicate having sheet structure is employed.
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) | 1978-05-12 | 1978-11-11 | 1979-05-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-12 | 1982-11-11 | 1983-05-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-12 | 1986-11-11 | 1987-05-13 | $7700.00 | Window Closed / Lapsed |