Synthesis and characterisation of a new sulphonated hydrocarbon polymer for application as a solid proton-conducting electrolyte

Nafion/sulfonated poly(indene) polyelectrolyte membranes for fuel cell application

“…Poly(indene) (PInd) has a repeating unit comprised of a five-membered ring with an aromatic ring attached to it, which easily undergoes electrophilic substitution with a sulfonic acid (-SO 3 H) group. Sulfonated poly(indene) (SPInd) shows thermal stability up to 200 ºC and good proton conductivity [12] . SPInd with DS 35 or 45% (SPInd35 and SPInd45, respectively) was used to prepare blended Nafion/SPInd membranes with 10, 15 or 20 wt.% SPInd.…”

“…The bands at 1410cm −1 and 850cm −1 correspond to S=O and S-OH stretching of the SO 3 H group and the band at 1052cm −1 was related to the symmetric SO 3 − stretching vibration [16] . For comparison, the FT-IR and NMR spectra for PInd and SPInd20 were reported in previous publications from our group [12,13] . Figure 2 shows the thermogravimetric (TG) and derivative (DTG) curves of recast Nafion and blended Nafion/SPInd membranes.…”

“…Nafion was modified with sulfonated poly(indene) (SPInd) using a simple, inexpensive process, aiming to improve the membrane water content, while maintaining good proton conductivity. SPInd was obtained through the sulfonation of poly(indene) with chlorosulfonic acid, previously reported by our group as a potential polymer electrolyte [12] . The SPInd has a thermally stable cyclic backbone with sulfonic groups attached to phenylene groups, making it hydrophilic.…”

Maghnite‐H+ Catalytic Synthesis and Characterization of Polyindenes and Oxidized Derivatives

“…Accordingly, PIns find potential application in areas such as solar energy systems, (photo)electronics, electrochromic devices, etc., apart from thermoplastics industry or gas separation . On the other hand, chemical modifications of PIns via sulfonation or hydrogenation have been studied to obtain polymers for proton‐exchange membrane fuel cells (PEMFCs) and/or with interesting thermal properties, respectively. Furthermore, oxidized PIns were found interesting for a variety of applications, and PIns and their composites with inorganic particles have exhibited interesting electrorheological properties …”

“…Various procedures to synthesize PIns can be found in literature, highlighting the electrochemical polymerization in CH 2 Cl 2 at room temperature; and chemical oxidative polymerization using different acidic/oxidizing catalysts and conditions: (i) AlCl 3 in CH 3 CH 2 Cl 2 , and cumyl methyl ether/TiCl 4 and CCl 3 COOH/ SnCl 4 in CH 2 Cl 2 , at low temperature (−20 to −65 °C); (ii) and FeCl 3 in CHCl 3 or concentrated H 2 SO 4 at ambient temperature 15–25 °C. All these processes to obtain PIn are based on the cationic polymerization mechanism and were carried out under inert atmosphere and anhydrous conditions.…”