Process for the preparation of a polyamide
US6828413B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 24, 2002 |
| Grant date | Dec 7, 2004 |
| Priority date | — |
| Expiry date | Jul 26, 2022 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G69/16
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The invention relates to a process for the preparation of a polyamide comprising at least a step in which a composition that comprises at least (a) a primary aminocarbonamide and (b) an aminocarboxylic acid and/or a lactam is polymerised, said composition comprising at least(a) 10-90 wt. % primary aminocarbonamide;(b) 10-90 wt. % aminocarboxylic acid and/or lactam;(c) 0-4 wt. % water;the amounts being relative to the sum of the compounds (a+b+c). Preferably the sum of the compounds (a+b+c) is at least 75 wt. % of the total composition, more preferably 85 wt. %, most preferably 90 wt. %.The polyamide obtained with the process has a &eegr;rel of more than 2.2.The process is eminently suitable for the preparation of polyamide-6 (polycapronamide) from a composition comprising 6-aminocapronamide, 6-aminocaproic acid and/or &egr;-caprolactam. This composition is preferably obtained via the reductive amination of a 5-formylyalerate ester, preferably 5-formylmethylvalerate in water. The 5-formylvalerate ester can for example be obtained from butadiene via (a) a carbonylation and (b) a hydroformylation reaction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.