| 학회 | 한국고분자학회 |
| 학술대회 | 2002년 가을 (10/11 ~ 10/12, 군산대학교) |
| 권호 | 27권 2호, p.2 |
| 발표분야 | 초청특별강연 |
| 제목 | POLYMERIC ELECTROLYTE MEMBRANE (PEM) NANOCOMPOSITES for FUEL CELLS VIA DIRECT POLYCONDENSATION |
| 초록 | Polymeric electrolyte membrane (PEM) based fuel cell systems for automobiles, homes, and portable power fuel cells are already important for high energy density and very good environmentally benign energy sources [1]. Currently, film forming fluorinated sulfonic acid containing copolymers are utilized primarily at 80℃ or lower for cost insensitive applications, such as the NASA space program. An increase in the fuel cell utilization temperature is desired for a number of reasons, including better efficiency and to improve the tolerance to impurities in fuels derived from H2 , methanol, natural gas, biomass or reformed gasoline, such as carbon monoxide. New and improved mechanisms for conductivity above the boiling point of water are needed, which operate with little or no water. We have been interested in the direct copolymerization of sulfonic acid containing monomers to afford ion conducting systems such as poly (arylene ethers), including sulfones and ketones, and naphthalene dianhydride 6 membered ring based polyimides. Both random (statistical) copolymers and block copolymers based on these two major classes of materials are being investigated [2-7]. Several of these systems are surprisingly highly compatible with important additives, e.g., heteropoly acids (HPA), such as phosphotungstic acid, and zirconium hydrogen phosphate, which have potential for allowing conductivity above 100℃. Highly dispersed nanocomposites have been achieved, which are possible because of specific interactions between the inorganic additive and the host copolymer, including hydrogen bonding, and dipolar interactions between the HPA and the sulfonic acid groups and/or backbone functionality. That highly dispersed HPA systems have been achieved can be demonstrated by FE-SEM, AFM and water extraction studies, and the fact that conductivity values of > 0.1 S/cm are possible at temperatures approaching 140℃. Excellent adhesion of the HPA to the matrix affords transparent mechanically robust films. In contrast, the fluorocopolymers under identical conditions produce opaque films in which the HPA is readily extracted by water. The synthesis and characterization of the polymer matrix systems, as well as the development of the nanocomposites and their thermal, mechanical, and conductivity characterization, will be presented with a particular orientation toward proton exchange membranes for fuel cells. Reference 1. http://education.lanl.gov/resources/fuelcells/ (LANL Website) 2. M.A. Hickner, F. Wang, B. Pivovar, T.A. Zawodzinski, and J.E. McGrath, “New Proton Exchange Membranes Via Direct Step or Polycondensation,” Electrochemical Society Meeting Proceedings, March 26, 2001, Washington, D.C. 3. F. Wang, M.A. Hickner, Q. Ji, W. Harrison, J.B. Mecham, T.A. Zawodzinski, and J.E. McGrath, Macromolecular Symposia, 175(1), 387-396, 2001. 4. M Hickner, Y.S. Kim, F. Wang, T.A. Zawodzinski, and J.E. McGrath, “Proton Exchange Membrane Nanocomposites,” Proceedings, American Society for Composites, 16th Annual Technical Conference, Virginia Tech, September 9-12, 2001. 5. F. Wang, M. Hickner, Y.S. Kim, T. Zawodzinski and J.E. McGrath, Journal of Membrane Science, 197 (2002), 231-242. 6. F. Wang, M. Hickner, Y.S. Kim, T. Zawodzinski, and J.E. McGrath, Polymer Preprints, 43, 000, (2002). 7. Y.S. Kim, M. Hill, F. Wang, M. Hickner, T.A. Zawodzinski, and J.E. McGrath, “Zirconium Hydrogen Phosphate/Sulfonated Poly(arylene ether sulfone) Copolymer Composite Membranes for Elevated Temperature Fuel Cell Applications,” AICHE Preprints, New Orleans, March 2002. |
| 저자 | James E. McGrath |
| 소속 | Virginia Polytechnic Institute and State Univ. |
| 키워드 | polymeric electrolyte membrane; fuel cell; nanocomposites; direct copolymerization |
| VOD | VOD 보기 |
