Characterisation of Silver-coated Teflon fabric-reinforced Nafion ionic polymer metal composite with carbon nanotubes and graphene nanoparticles

Teflon fabric-reinforced Nafion (TFRN) is a novel perfluorosulfonic acid polymer membrane with good proton conductivity, mechanical-thermal stability and good bio-compatibility. In this investigation, the viscoelastic behaviour of Nafion 438 (TFRN membrane) was observed using dynamic mechanical analysis (DMA) after coating with silver, silver with carbon nanotubes (CNT) and silver with graphene nanoparticles on both sides of the Nafion 438 (N438) membrane using chemical decomposition technique. The investigation results are compared and verified with the storage modulus (E-l), loss modulus (E-ll) and glass transition temperature (T-g) of the samples. A drastic rise in the E-l value indicates that the strength of the material has enhanced compared to the original pure TFRN. In creep analysis, the membrane of N438 coated with silver (Ag) showed less creep resistance, due to its pendant groups and degree of secondary bonding. The T-g values increased by above 89.39% for all samples and showed higher T-g values of 220 degrees C and 210 degrees C for N438 coated with Ag-CNT (0.01 w/v ratio) and Ag membrane. Whereas, Ag-graphene-coated N-438 exhibited higher strength (2.6 x 10(11) Pa) and viscoelastic nature with lower T-g values. This divulges that N438 ionic polymer metal composite (IPMC) membrane has superior mechanical properties compared to pure N438. At the end, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were brought into focus for thermal characterization of the samples. From the DSC and TGA thermograms, strong and weak endothermic peaks were observed between 310 and 400 degrees C for all samples and noticed that these samples are thermally stable below 420 degrees C. [GRAPHICS] .

Automated summary

In this study, the viscoelastic behavior of Teflon fabric-reinforced Nafion (TFRN) membrane was observed after coating with silver, silver with carbon nanotubes, and silver with graphene nanoparticles. The results showed that the coated membranes had enhanced strength and different levels of creep resistance. The addition of graphene nanoparticles resulted in higher strength and lower glass transition temperatures. Differential scanning calorimetry and thermogravimetric analysis were used to characterize the thermal properties of the samples, indicating that they were thermally stable up to 420 degrees C.