| 主权项 |
1. A process for preparing a semiaromatic polyamide, comprising:
a) providing a reactant composition comprising
A) at least one unsubstituted or substituted aromatic dicarboxylic acid or a derivative thereof, andB) at least one aliphatic or cycloaliphatic diamine, or a salt of at least one compound A) and at least one compound B), b) feeding the reactant composition provided in step a) into at least one polymerization zone and subjecting the reactant composition to a polymerization at elevated temperature and, at least at the start of the polymerization, at elevated pressure, c) withdrawing a water-containing gas phase from the polymerization zone in the course of the polymerization, with the proviso that the diamine component B) is used in the reactant composition with a stoichiometric excess of 300 to 650 meq/kg, wherein the stoichiometric excess of the diamine component B) in the reactant composition is increased by any portion of the diamine component B) which is discharged from the polymerization zone together with the water-containing gas phase in the course of the polymerization. |
