Fuel Cell Nanomaterials Center, University of Yamanashi, 4 Takeda, Kofu 400-8510, Japan.
ACS Appl Mater Interfaces. 2009 Jun;1(6):1279-86. doi: 10.1021/am900165w.
A series of sulfonated poly(arylene ether sulfone)s (SPEs) block copolymers containing fluorenyl groups were synthesized. Bis(4-fluorophenyl)sulfone (FPS) and 2,2-bis(4-hydroxy-3,5-dimethylpheny)propane were used as comonomers for hydrophobic blocks, whereas FPS and 9,9-bis(4-hydroxyphenyl)fluorene were used as hydrophilic blocks. Sulfonation with chlorosulfonic acid gave sulfonated block copolymers with molecular weight (M(w)) higher than 150 kDa. Proton conductivity of the SPE block copolymer with the ion exchange capacity (IEC) = 2.20 mequiv/g was 0.14 S/cm [80% relative humidity (RH)] and 0.02 S/cm (40% RH) at 80 degrees C, which is higher or comparable to that of a perfluorinated ionomer (Nafion) membrane. The longer hydrophilic and hydrophobic blocks resulted in higher water uptake and higher proton conductivity. Scanning transmission electron microscopy observation revealed that phase separation of the SPE block copolymers was more pronounced than that of the SPE random copolymers. The SPE block copolymer membranes showed higher mechanical properties than those of the random ones. With these properties, the SPE block copolymer membranes seem promising for fuel-cell applications.
一系列含有芴基的磺化聚(芳醚砜)(SPE)嵌段共聚物被合成出来。双(4-氟苯基)砜(FPS)和 2,2-双(4-羟基-3,5-二甲基苯基)丙烷被用作疏水性嵌段的共聚单体,而 FPS 和 9,9-双(4-羟基苯基)芴则被用作亲水性嵌段。用氯磺酸磺化得到了分子量(M(w))高于 150 kDa 的磺化嵌段共聚物。离子交换容量(IEC)为 2.20 mequiv/g 的 SPE 嵌段共聚物的质子电导率在 80°C 时为 0.14 S/cm [80%相对湿度(RH)]和 0.02 S/cm(40% RH),高于或可与全氟离子交换膜(Nafion)相媲美。较长的亲水性和疏水性嵌段导致了更高的吸水率和更高的质子电导率。扫描透射电子显微镜观察表明,SPE 嵌段共聚物的相分离比 SPE 无规共聚物更为明显。SPE 嵌段共聚物膜具有比无规共聚物更高的机械性能。由于这些特性,SPE 嵌段共聚物膜似乎在燃料电池应用方面具有广阔的前景。