| 摘要 |
The process for preparing a polyamide based on dicarboxylic acids and diamines has the following stages: 1) providing an aqueous monomer mixture of dicarboxylic acids and diamines, the molar ratio of dicarboxylic acids to diamines being adjusted such that a molar deficiency of dicarboxylic acids or diamines of from 1 to 10 mol % is present at the outlet of stage 3), based on the other component in each case, 2) transferring the aqueous mixture from stage 1) to a continuous evaporator reactor in which diamines and dicarboxylic acids are reacted at a temperature in the range from 100 to 370° C. and a pressure in the range from 1 to 50 bar, 3) transferring the mixture from stage 2) to a separator which is operated at a temperature in the range from 100 to 370° C. with removal of gaseous components, 4) transferring the mixture from stage 3) together with diamine or dicarboxylic acid in an amount suitable to balance out the molar deficiency into an extruder which is operated at a temperature in the range from 150 to 400° C. for a residence time in the range from 10 seconds to 30 minutes to remove gaseous components through devolatilizing orifices.
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