Preparation of carboxyl-containing polymers

Abstract From the Canadian patent

A process for polymerizing olefinically unsaturated carboxylic acids contaning at least one activated carbon-to-carbon olefinic double bond and at least one carboxyl group in benzene in the presence of block copolymers of propylene oxide and ethylene oxides having molecular weights in the range of greater than about 1600 to about 20,000 resulting, in improved yields of carboyxl-containing polymers such as cross-linked polyacrylic acid as shown by an increase in total solids of the benzene slurry of about 50 percent, the polymers obtained at this higher total solids having increased bulk density.