Patent ID: 6274668
Filing Date: 2001-08-14
Classification: C08F,Y10S

Abstract:
A process of reducing the content of residual monomers in dispersions or emulsions obtained by polymerization or copolymerization of aqueous phase acrylic monomer, includingadding a redox couple comprisinga reducing agent selected from the group consisting of ascorbic acid or an aldehyde having four or more carbon atoms and containing at least an organic or inorganic salifiable hydrogen, or its salts, the inorganic salifiable hydrogen being added to a carboxylic group; the aldehyde reducing agent or its salts being at least 5% by weight soluble in water;an oxidizing agent, said oxidizing agent being a salt of a hydroperoxide in aqueous solution,the residual monomers in the dispersion or emulsion having a total VOC content lower than 600 ppm, a VOC content deriving from the monomers utilized to obtain the dispersion or emulsion lower than 100 ppm, a wet coagula content of 500 ppm or less after wet filtering on 125 micron filter of the dispersion or emulsion at the outlet after the various reduction phases.