文摘
In the present work, a new sulfonated tetraamine and the corresponding sulfonated polybenzimidazoles (sPBI) were synthesized. For the sake of determining the best polymerization conditions, a study involvingmodel compounds was first performed. A strong acid medium was used as polymerization solvent, which allowedto obtain high molecular weight sPBI. A series of polymers with ion exchange capacity (IEC) ranging from 0 to2.6 mequiv/g were synthesized using a non-sulfonated tetraamine as a comonomer. The chemical structure ofthose polymers was confirmed by nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) aswell as by titration. Thermogravimetric analysis (TGA) and viscosity measurement were performed as well. Onthe other hand, different architectures of the copolymers were prepared, i.e., random, sequenced copolymers, andblends of the homopolymers. The membranes prepared from the sPBI display low water uptake. The ionicconductivities measured in the hydrated state at room temperature ranged from 10-6 to 4 × 10-4 S cm-1.