Polyethylene support in form of net or fabric, comprising, grafted on the surface of said support, a hydrogel comprising polyvinylpyrrolidone. Method for preparing said support comprising the steps of: immersing the support in a toluene solution (Sol1) containing: ethylene glycol dimethylacrylate (EGDMA) and cumene hydroperoxide (CHP)； immersing the support in an aqueous solution (Sol2) containing: FeCl2*4H2O, ascorbic acid and polyvinylpyrrolidone (PVP)； washing and drying the support.
