Method for producing polyamides

Polyamides, oligomers thereof or mixtures thereof, if required with further reaction products, are prepared by reacting aminonitriles or dinitriles and diamines or a mixture containing aminonitrile, dinitrile and diamine, and, if required, further polyamide-forming monomers and/oligomers with water in a reactor ( 1 ) having a vertically oriented longitudinal axis, by a process in which, in the reactor ( 1 ), the reaction product is removed from the bottom and ammonia formed and any further low molecular weight compounds formed and water are taken off via the top ( 2 ), wherein the reactor ( 1 ) has at least two chambers ( 4 ) arranged one on top of the other in the longitudinal direction, the chambers ( 4 ) being separated from one another by liquid-tight trays ( 5 ), each chamber ( 4 ) being connected by a liquid overflow ( 6 ) to the chamber ( 4 ) directly underneath and a liquid product stream being taken off by the liquid overflow ( 6 ) of the lowermost chamber ( 4 ), the gas space ( 7 ) above the liquid level in each chamber ( 4 ) being connected to the chamber ( 4 ) arranged directly above in each case by one or more conduit pipes ( 8 ) which in each case opens or open into a gas distributor ( 9 ) having orifices ( 11 ) for gas exit below the liquid level, and comprising in each case at least one baffle plate ( 12 ) which is arranged vertically around each gas distributor ( 9 ) and whose upper end terminates below the liquid level and whose lower end terminates above the liquid-tight tray ( 5 ) of the chamber ( 4 ) and which separates each chamber ( 4 ) into one or more gassed ( 13 ) and into one or more ungassed ( 14 ) spaces.