Hydroquinone Based Sulfonated Copolytriazoles with Enhanced Proton Conductivity

A series of new fluorinated sulfonated copolytriazoles (PTHQSH‐XX) with ion exchange capacity (IEC_w) values ranging from 1.66 to 2.82 meq g⁻¹ are prepared via cuprous ion catalyzed azide‐alkyne click polymerization reaction between 1,4‐bis(prop‐2‐ynyloxy)benzene, 4,4′‐diazido‐2,2′‐stilbene disulfonic acid disodium salt (SA), and 4,4‐bis3′‐trifluoromethyl‐4′(4‐azidobenzoxy) benzyl] biphenyl (QAZ). The degree of sulfonation of the copolytriazoles is adjusted between 60% and 90% by varying the molar ratio of sulfonated monomer (SA) to the nonsulfonated monomer (QAZ). The structure of the copolytriazoles is characterized by Fourier transform infrared and NMR spectroscopy. The solution‐cast membranes of these copolymers exhibit high thermal, mechanical, oxidative and hydrolytic stability, and high proton conductivity (19–142 mS cm⁻¹ at 80 °C and 22–157 mS cm⁻¹ at 90 °C). Transmission electron microscopy confirms the formation of good phase separated morphology with ionic clusters in the range of 15–145 nm.