| 摘要 |
<p>Disclosed is a process for the preparation of polyamide 66 from an aqueous solution of hexamethylene diamine adipic acid salt (AH salt), wherein a solution of AH salt is first concentrated. The concentration is done in at least two steps, by at least two concentrators in series. The staged concentration is combined with subsequent polymerization in a plurality of reactors placed in parallel and operated in a batch mode. The process allows considerable energy-saving, by applying the steam from one concentrator as a heating medium in another concentrator.</p> |
