以新型磺化二胺单体,1,4-双(4-胺基-2-磺酸基苯氧基)苯(DS—TBDA)与非磺化单体1,4'-二胺基二苯醚(0DA)、1,4,5,8-萘四酸二酐(NTDA)为原料,采用高温聚合法,制备了一系列具有不同磺化度的萘酐型磺化聚酰亚胺(S—PI)质子交换膜材料,并研究了材料性能与结构的关系.磺化度超过33%时,质子传导率可达到与Nafion膜同一数量级的水平,而甲醇透过率均在2.85×10^-7cm^2/s以下,比Nafion膜低1.2个数量级.研究结果表明,该膜有望在直接甲醇燃料电池(DMFC)中获得应用.
To prepare proton conductive membrane for DMFC, a novel sulfonated diamine 1,4-bis (4-amino- 2-sulfonic-phenoxy)-benzene (DS-TBDA) was synthesized and polymerized with a non-sulfonated diamine (ODA) and naphthalene-1,4,5,8-tetracaboxylic dianhydride(NTDA) to get a series of naphalenic sulfonated polyimides(S-PI). The sulfonation degree of the polymers was controlled by changing the molar ratio of the monomers. The obtained SPI membrane was characterized by FTIR and the properties, such as water uptake, proton conductivity and methanol permeability, were investigated. With the increase of sulfonation degree, the proton conductivity and methanol permeability raise gradually. The proton conductivities of the SPI membranes are in a range of from 0. 007 9 to 0. 072 S/cm and the methanol permeability is less than 2.85 × 10^ -7 cm^2/s. The experiment result indicats they are great potential candidates for fuel cell applications.