▎ 摘　　要

NOVELTY - Hydrophobic agent composition comprises 68-70 pts. wt. polytetrafluoroethylene micropowder, 8-10 pts. wt. polypropylene powder, 8-10 pts. wt. nano-graphene powder and 8-10 pts. wt. polyvinyl alcohol as granulation binder. USE - The hydrophobic agent composition is useful for long-life hydrogen fuel cell gas diffusion layer (claimed). ADVANTAGE - The hydrophobic agent: utilizes nano-graphene powder, which can improve strength of the hydrophobic agent; has sufficient strength to support the membrane electrode to avoid deformation due to excessive water absorption of the carbon paper after the hydrophobic agent is coated on the surface of the carbon paper; ensures the passage of the reaction gas; discharges the water of the fuel cell reaction; and avoids the problem of flooding. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparing hydrophobic agent comprising (i) mixing and stirring polytetrafluoroethylene micropowder, polypropylene powder and nano-graphene powder for 40-50 minutes to obtain prefabricated materials, (ii) adding the granulation binder polyvinyl alcohol into pure water and heating to dissolve to obtain aqueous polyvinyl alcohol solution, then spraying aqueous polyvinyl alcohol solution onto the prefabricated material, drying and agglomerating to obtain granulated powder, (iii) adding the granulated powder into a injection device and spraying it evenly on the carbon paper, (iv) adding the carbon paper into an air oven for drying, and (v) taking out the carbon paper, adding the carbon paper into a vacuum oven for semi-melting to obtain hydrophobic agent.