| 摘要 |
FIELD: chemistry.SUBSTANCE: method of producing polyamide by direct polycondensation of a diamine component and a dicarboxylic acid component involves: adding the diamine component, which contains 70 mol % or more p-xylylenediamine, to the dicarboxylic acid component, which contains 70 mol % or more of a straight-chain aliphatic dicarboxylic acid, which is kept in molten state by heating to melting point thereof or higher, while keeping the reaction mixture in a molten state under pressure; and reducing the pressure of the reaction system to atmospheric pressure for 50 minutes or longer at a rate of 1.0 MPa/h or less, after adding the diamine component.EFFECT: method provides easy production of a polyamide with low molecular weight dispersion.4 cl, 4 ex |
