US3909498A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparing granular powdered polyamide
Assignee: Stamicarbon BV
•
Filing: 1973-07-13
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Granted: 1975-09-30
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Expires: 1993-07-13
Abstract
Abstract A process for the preparation of polyamides in granular or powdered form is described, said process comprising heating a lactam or mixture of lactams in a suitable inert solvent at a temperature below the melting point of the polyamide to be formed, in the presence of a conventional anionic catalyst and a conventional promotor. The disclosure points out that the presence during polymerisation of one or more compounds from the group of alcohols, carboxylic esters and inert salts, dissolved or dispersed in the solvent, prevents the formation of lumps and the adhesion of the polyamide to the reactor walls.
Inventors
- 👤 Wilhelmus P Wolvers
- 👤 Jean M M Warnier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 11:02
CPC Classifications
C; C08; C08G; C08G69/00; C08G69/02; C08G69/08; C08G69/14; C08G69/16; C08G69/18
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
124 words
IN A PROCESS FOR PREPARING A GRANULAR OR POWDERED POLYAMIDE BY THE SOLUTION POLYMERIZATION OF A LACTAM OR MIXTURE OF LACTAMS IN AN INERT SOLVENT BY MEANS OF AN ANIONIC CATALYST AND A PROMOTER AT A TEMPERATURE BELOW THE MELTING POINT OF THE POLYAMIDE WHICH IS TO BE FORMED, THE IMPROVEMENT COMPRISING THE PRESENCE, DISSOLVED OR DISTRIBUTED IN THE SOLVENT, OF AT LEAST ONE MODIFIER SELECTED FROM THE GROUP CONSISTING OF ALCOHOLS CONTAINING FROM 6-30 CARBON ATOMS AND CARBOXYLIC ESTERS DERIVED FROM ALIPHATIC ALCHOLS CONTAINING 5-30 CARBON ATOMS, AND A MONOVALENT OR POLYVANT CARBOXYLIC ACID CONTAINING 5-30 CARBON ATOMS, DURING SAID POLYMERIZATION, WHEREIN THE AMOUNT OF MODIFIER IS ABOUT 20 TO ABOUT 200 MOLE PER CENT, CALCULATED WITH RESPECT TO THE AMOUNT OF PROMOTER.
Claim 2
Dependent Claim
124 words
IN A PROCESS FOR PREPARING A GRANULAR OR POWDERED POLYAMIDE BY THE SOLUTION POLYMERIZATION OF A LACTAM OR MIXTURE OF LACTAMS IN AN INERT SOLVENT BY MEANS OF AN ANIONIC CATALYST AND A PROMOTER AT A TEMPERATURE BELOW THE MELTING POINT OF THE POLYAMIDE WHICH IS TO BE FORMED, THE IMPROVEMENT COMPRISING THE PRESENCE, DISSOLVED OR DISTRIBUTED IN THE SOLVENT, OF AT LEAST ONE MODIFIER SELECTED FROM THE GROUP CONSISTING OF ALCOHOLS CONTAINING FROM 6-30 CARBON ATOMS AND CARBOXYLIC ESTERS DERIVED FROM ALIPHATIC ALCHOLS CONTAINING 5-30 CARBON ATOMS, AND A MONOVALENT OR POLYVANT CARBOXYLIC ACID CONTAINING 5-30 CARBON ATOMS, DURING SAID POLYMERIZATION, WHEREIN THE AMOUNT OF MODIFIER IS ABOUT 20 TO ABOUT 200 MOLE PER CENT, CALCULATED WITH RESPECT TO THE AMOUNT OF PROMOTER.
Claim 3
Dependent Claim
24 words
Process according to claim 1, characterized in that the amount of modifier is 25-100 moles %, calculated with respect to the amount of promoter.
Claim 4
Dependent Claim
21 words
Process according to claim 1, characterized in that the modifiers used is a monovalent or polyvalent alcohol with 6-30 carbon atoms.
Claim 5
Dependent Claim
32 words
Process according to claim 1, characterized in that the modifier used is an ester derived from a monovalent aliphatic alcohol with 6-30 carbon atoms and a monocarboxylic acid with 5-30 carbon atoms.
Claim 6
Dependent Claim
42 words
Process according to claim 1, characterized in that the promoter used in a compound that is capable of changing a lactam melt into a solid polyamide within 5 minutes at a temperature of 180*C and a promoter concentration of 1.0 mole %.
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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) | 1978-09-29 | 1979-03-31 | 1979-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-29 | 1983-03-31 | 1983-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-29 | 1987-03-31 | 1987-09-30 | $7700.00 | Window Closed / Lapsed |