Patent ID: 6521782
Filing Date: 2003-02-18
Classification: C07C

Abstract:
A process for the manufacture of aqueous solutions of unsaturated quaternary ammonium salts corresponding to the following formula (I): in which R represents a methyl or benzyl radical, by reaction, in the presence of water, of N,N-dimethyl-aminoethyl acrylate (DAMEA) with a quaternizing agent of formula (II): Râ€”Clâ€ƒâ€ƒ(II) â€ƒin which R is as defined above, (a) the reaction is carried out in a closed reactor, which comprises all the DAMEA and which has been pressurized by air or depleted air to 0.5 to 3 bar, by continuously introducing, at a temperature of 35 to 65Â° C., the quatemizing agent (II) and the water, until a concentration of salt (I) in the water is obtained, the start of the introduction of the water beginning when 0-20% of the amount by weight of the quaternizing agent (II) necessary for the reaction has been added and it being possible for the pressure at the end of the reaction to reach 9 bar; then (b) the reactor is depressurized while keeping the oxygen content constant by simultaneous introduction of air and, after returning to atmospheric pressure, the residual quaternizing agent is removed.