초록 |
Poly(tetrafluoroethylene-co-hexafluoropropylene) (FEP) film was grafted with styrene monomer for usage of fuel cell as polymer electrolyte membrane. Two irradiation methods, pr-irradiation andsimultaneous, were compared each other. Simultaneous irradiation method was superior to pre-irradiation one, which leads to high degree of grafting with uniform distribution inside film. Grafting was almost accomplished within 24 hours with doses of 10-100kGy and grafting temperature of 24-60oC, and it is more sensitive to grafting temperature than irradiation dose. Simultaneous irradiation method can make the distribution profile of sulfur components be almost uniform across film within two hours, leading to high values of IEC and IC. Such properties as IEC, IC and methanol crossover for FEP membrane manufactured in this study were superior to Nafion membrane commercialized. |