Graft polymerization and crosslinking in radiation processing are attractive techniques for modification of the chemical and physical properties of conventional polymers. The graft polymerization and subsequent chemical treatment can introduce a chelate agent function into a conventional polymer such as polyethylene. The obtained amidoxime fibrous adsorbent was applied to the recovery of uranium from seawater. Soaking of 350kg adsorbent 12 times in seawater led to the collection of 1kg of uranium. Natural polymers such as derivatives of starch and cellulose were radiation-crosslinked to form hydrogels. Mats of crosslinked carboxylmethyl cellulose were evaluated by 68 patients after surgical operation. No bedsore was observed in almost of all patients after operation. This product was commercialized as “Non-bedsore” in Japan.