Abstract: Water-insoluble, water-swellable fibers adapted to bind aqueous fluids such as body exudates are prepared by spinning fibers from an organic solvent solution of a copolymer of maleic anhydride with suitable vinyl monomers. The copolymer solution also contains a small amount of a polyfunctional cross-linking agent such as a glycol or alkylene diamine which reacts to cross-link the copolymer chains when the fibers are heated and dried. The cross-linked copolymer fibers are then rendered hydrophilic and water-swellable by reaction with ammonia or an alkali metal hydroxide.