| 초록 |
Poly(vinyl alcohol) (PVA) membranes have been used in ethanol dehydration to break the ethanol-water azeotrope. Therefore PVA membrane is expected to decrease methanol permeability in DMFC. However, the highest reported proton conductivity is only 3.65 × 10-5 S/cm. To improve the proton conductivity of the PVA membranes, a number of research groups have investigated several combinations of PVA with acid or salts, such as phosphoric acid (H3PO4), etc. PVA membranes doped with H3PO4 shows higher proton conductivity, but PVA-H3PO4 blend is very soft, water soluble, and H3PO4 leaches out of the membrane easily and the proton conductivity drops rapidly. In order to overcome these drawbacks, we synthesized poly(Vinylphosphate-b-styrene) copolymer (Poly(VPP-b-St)) via consecutive telomerization of vinyl acetate (VAc), ATRP with styrene, saponification, and phosphorylation with phosphorous oxychloride. Then, the blend membranes of PPO with poly(VPP-b-St) were prepared by solution casting method. |
