▎ 摘　　要

NOVELTY - A phosphonic acid modified graphene oxide crosslinked polyolefin grafted benzimidazole polymer composite material comprises polyolefin grafted benzimidazole polymer and phosphonic acid-modified graphene oxide. The phosphonic acid in the phosphonic acid-modified graphene oxide is selected from amino-containing phosphonic acid compounds. USE - The phosphonic acid modified graphene oxide crosslinked polyolefin grafted benzimidazole polymer composite material used for proton exchange membrane in the field of fuel cells or flow batteries (claimed). ADVANTAGE - The product has phosphoric acid doping level reduced to below 9, realizes improved proton conductivity of up to 10x 10-2 S/cm, the transverse swelling rate after immersion in phosphoric acid is as low as 6.9%, and the tensile strength exceeds 8 MPa.