| 摘要 |
To prepare nitrogen-containing polycondensates, a starting substance which still contains reactive end groups is dispersed in a high-boiling inert solvent, preferably in the presence of a dispersing auxiliary, low molecular weight by-products are distilled off at elevated temperature, the batch is cooled and the dispersed polycondensate is isolated. To prepare the starting substance, a mixture of at least two monomers which react with one another is heated up to a constant reaction temperature, a melt being formed at least in part, but initially no homogeneous melt occurring. The reaction is continued until a homogeneous melt is present. The precondensate formed is then dispersed in the high-boiling inert solvent and the condensation reaction is brought to completion.
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