▎ 摘　　要

NOVELTY - Phosphonic acid modified graphene oxide crosslinked polybenzimidazole-polysiloxane block copolymer composite material comprises polybenzimidazole-polysiloxane block copolymer and phosphonic acid-modified graphene oxide. The phosphonic acid in the phosphonic acid modified graphene oxide is selected from amino-containing phosphonic acid compound. USE - The phosphonic acid modified graphene oxide crosslinked polybenzimidazole-polysiloxane block copolymer composite material is used for proton exchange membrane useful in the field of fuel cell or liquid flow cell (all claimed). ADVANTAGE - In the composite material, phosphonic acid-modified graphene oxide is introduced into the polybenzimidazole-polysiloxane block copolymer by the form of a covalent bond, and because the introduction of a small amount of phosphonic acid modified graphene oxide makes the phosphoric acid doping level further reduced to less than 10, and proton conductivity is greatly improved and can reach 8.31x 10-2 S/cm, the transverse swelling rate after phosphoric acid immersion reaches 8.7%, the tensile strength is more than 7.5 MPa. The modification of the phosphonic acid modified graphene oxide in the composite material improves the compatibility and bonding force with the polybenzimidazole-polysiloxane block copolymer, which not only improves the ion conductivity, but further reduces the phosphoric acid doping level (ADL), improves the anti-swelling performance and mechanical performance, and optimizes the comprehensive performance of the composite material.