Abstract: Lightly cross-linked, water-insoluble copolymers of maleic anhydride with suitable vinyl monomers are dispersed with the aid of a surfactant in a cellulosic pulp slurry or papermaking furnish to prepare molded pulp or paper products incorporating said copolymer in finely divided form. The resulting product is treated with an alkaline agent such as ammonia gas or an alcoholic solution of an alkali metal hydroxide to convert the copolymer to a water-swellable salt form whereby the treated molded pulp or paper product has a high absorbency for aqueous fluids.