2016-08-242016-08-241996-06-25http://hdl.handle.net/10919/72320A method is described for the chemical modification of pre-shaped hydrogels in non-aqueous medium. The conditions permit the reaction of highly expanded, porous hydrogel particles, such as spherical beads, using pseudo homogeneous reaction conditions in the absence of water. The method involves a three step procedure in which the porous gels are solvent exchanged int a water-free solvent (step 1) with minimal change in gel dimension and porosity; followed by reaction under non-aqueous condition (step 2); and followed by solvent exchange into water (step 3). Many different types of reactions requiring non-aqueous conditions may be carried out using these conditions. The method has particularly been demonstrated for crosslinking fluorinating beads, and for esterifying beads in a reaction involving multifunctional free carboxylic acids in the presence of dicyclohexylcarbodiimide (DCC).application/pdfen-USPatenthttp://pimg-fpiw.uspto.gov/fdd/11/301/055/0.pdf8296171536/56536/58536/84536/124C08B3/00C08B3/145530111