| abstract |
The invention relates to a method for reacting synthetic poly(carboxylic acids) (A), containing at least 10 repetitive structural units of formula (I), wherein R9 represents hydrogen, a C1 to C4-alkyl group or a group of formula -CH2-COOH, R10 represents hydrogen or a C1 to C4-alkyl group, R11 represents hydrogen, a C1 to C4 alkyl group or -COOH or with amines (B) of general formula (II) HNR1R2 (II), wherein R1represents a hydrocarbon group having 3 to 50 C atoms, which can be substituted or can contain heteroatoms, and R2 represents hydrogen or a hydrocarbon group having 1 to 50 C atoms, which can be substituted or can contain heteroatoms, or R1 and R2 together form a ring with the nitrogen atom to which they are bound. According to the invention, a reaction mixture containing at least one synthetic poly(carboxylic acid) (A) and at least one amine of formula (II) in a solvent mixture which contains water, and with respect to the weight of the solvent mixture, 0.1 - 75 wt.-% of at least one organic solvent which can be mixed with water.,said organic solvent having a dielectric constant of at least 10 when measured at 25 °C, is introduced into a reaction path and is exposed to microwave radiation when it flows through the reaction path. Said reaction mixture is heated to temperatures over 100 °C by the microwave radiation in the reaction path. |