One-pot method for the synthesis of sulfonated poly(1,3,4-oxadiazoles) based on 4,4’-oxydibenzoic acid

Electrospun Separator Based on Sulfonated Polyoxadiazole with Outstanding Thermal Stability and Electrochemical Properties for Lithium-Ion Batteries

“…16−20 The solubility of PODs in common polar organic solvents, such as dimethyl sulfoxide (DMSO), dimethylformamide (DMF), and N-methyl pyrrolidone (NMP), can be easily improved by sulfonation during polymerization using oleum as both the solvent and sulfonating agent. 21,22 Due to their unique properties, the sulfonated PODs are extensively studied as proton-conducting membranes, 18,21,23−25 whereas, to the best of our knowledge, no separators based on sulfonated PODs for LIBs have been reported yet. In the sulfonated POD macromolecular structure, the abundant heteroatoms and sulfonate groups can not only enhance the electrolyte wettability and the Li + migration 10,14,24,26−28 but also benefit the improvement of the electrolyte's lithium-ion transference number (t Li + ) mainly by retarding anionic movement via electrostatic repulsion.…”

“…In the sulfonated POD macromolecular structure, the abundant heteroatoms and sulfonate groups can not only enhance the electrolyte wettability and the Li + migration 10,14,24,26−28 but also benefit the improvement of the electrolyte's lithium-ion transference number (t Li + ) mainly by retarding anionic movement via electrostatic repulsion. 29,30 Moreover, the sulfonated PODs are expected to possess a flame-retardant property, 21,22 which is a crucial factor for the security of LIBs as well.…”

Sulfonated polyoxadiazole synthesis and processing into ion‐conducting films

“…For film formation, it is necessary to know the appropriate solvents, while the feature of rigid-chain polymers with fragments of oxadiazole and DE is their solubility only, as far as is known, in concentrated sulfuric acid. 50 Therefore, a separate task is to find suitable solvents or mixtures thereof for the processing of such polymers. Moreover, for processing through solutions, it is necessary to choose the temperature conditions and polymer concentration, i.e.…”

“…In addition, it is known that the introduction of both phenoxathiine and phenoxathiine‐10,10‐dioxide (PD) into the macromolecular chain contributes to the growth of thermal stability 48,49 . Early, the possibility of one‐pot synthesis of sulfonated copolymers containing fragments of p ‐phenylene‐1,3,4‐oxadiazole, PD and DE was demonstrated using 4,4′‐oxybis(benzoic acid), terephthalic acid and hydrazine sulfate in the oleum medium 50,51 . These copolymers were hydrophobic due to the content of p ‐phenylene units, but nothing should interfere with the preparation of copolymers without them, which would also increase the relative content of sulfonic acid groups.…”

“…Since sulfonated aromatic polymers do not usually melt, their films can only be obtained from solutions. For film formation, it is necessary to know the appropriate solvents, while the feature of rigid‐chain polymers with fragments of oxadiazole and DE is their solubility only, as far as is known, in concentrated sulfuric acid 50 . Therefore, a separate task is to find suitable solvents or mixtures thereof for the processing of such polymers.…”