Process for the production of aqueous dispersions of solid free radical-generating initiators

The process for the production of stable aqueous dispersions of free radical-generating polymerization initiators that are solid at temperatures above 0.degree. C. that comprises the steps of

• (a) forming a suspension that contains from 10% to 40% by weight of a free radical-generating polymerization initiator that is solid at temperatures above 0.degree. C. in an aqueous medium that comprises from 1% to 5% by weight of a suspending agent selected from the group consisting of water-soluble cellulose derivatives, gelatin, polyvinyl alcohol, starch, methyl vinyl ether-maleic anhydride copolymers, vinyl acetate-maleic anhydride copolymers, metal salts of carboxymethylcellulose and polyacrylic acids, and mixtures thereof;
• from 0.1% to 2% by weight of a wetting agent selected from the group consisting of polyoxyethylene alkyl ethers, polyoxyethylene alkyl esters, polyoxyethylene alkyl aryl ethers, sorbitan alkyl esters, polyoxyethylene-propylene glycol ethers, polyoxyethylenesorbitan alkyl esters, fatty acid monoglycerides, fatty acid soaps, sulfates, alkyl aryl sulfonates, dialkylsulfosuccinates, alkyl sulfonates, ethylene oxide adducts of alkylphenols, and mixtures thereof;
• and from 8% to 20% by weight of a polyalkylene glycol, said percentages being based on the weight of the suspension, and
• (b) homogenizing said suspension to form a stable initiator dispersion.