| 摘要 |
A process is disclosed for continuously preparing polyamides from a mixture of at least one lactam and water, as well as if required other monomer units and/or usual additives and fillers in polyamide-forming conditions. The mixture of initial substances is heated in the liquid phase in a first reaction zone until a conversion rate of at least 70% is reached, then is adiabatically expanded and further polymerised in another reaction zone. In the first reaction zone, 0.5 to 7 % by weight water are added to the mixture, the mixture is heated up to a temperature range from 220 to 310 .degree.C and polymerised until a conversion rate of at least 85 % is reached. In the second reaction zone, after the mixture is expanded, it is further polymerised at temperatures in a range from 215 to 300 .degree.C without further heating.
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