The present invention is directed to an improved process for producing a viscosifying polymer. The process of the present invention comprises the steps of copolymerizing a carboxylic acid monomer and a polyfunctional cross-linker monomer in an effective mole ratio in a silicone solvent under an inert atmosphere in the presence of an effective amount of an initiator to form a viscosifying polymer that in a 0.5% by weight aqueous mucilage exhibits a viscosity of about 50,000 to 300,000 cps. The present invention is further directed to a viscosifying copolymer comprising a cross-linked copolymer of a carboxylic acid monomer and a polyfunctional cross-linker monomer, the viscosifying copolymer characterized in that a 0.5% by weight aqueous mucilage of the viscosifying copolymer exhibits a viscosity of about 50,000 to 300,000 cps. A preferred viscosifying copolymer includes acrylic acid as the carboxylic acid monomer and allyl methacrylate monomer as the polyfunctional cross-linker.