Hydrophilic monomer 2-hydroxyethyl acrylate（HEA） and a series of polyethylene glycol dimethacrylate monomers were copolymerised by radiation technique at low temperature（-78℃） and hydrophilic were obtained.The immobilization of yeast cells with these copolymeried carriers led to a higher ethanol productivity than free cells.Of all copolymer carriers

the ethanol yield with poly（HEA-14G） was the highest

about 2.45 times as high as that of free yeast cells.In addition

the ethanol productivity of 12 batch repeated reactions with poly（HEA-14G） carrier was all higher than that of free yeast cells.The ethanol productivity of immobilized yeast cells was dependent on the proportion of hydrophilic monomer to other monomers in copolymer systems

the chain length of the bifunctional monomer

the degree of hydration of copolymer carriers

the structure of copolymer carriers and porosity in the internal structure of carriers.The ethanol yield of immobilized cells depended on swelling ability and porosity of copolymer carriers.