The present invention provides methods of making covalently crosslinked vinyl polymer hydrogels having advantageous physical properties, and covalently crosslinked vinyl polymer hydrogel compositions made by such methods, as well as articles of manufacture comprising such covalently crosslinked vinyl...http://www.google.es/patents/US7985781?utm_source=gb-gplus-sharePatente US7985781 - PVA hydrogel
