Structural and electrochemical properties of PEO/PAN nanofibrous blends: Prediction of graphene localization

Quasi-solid-state electrolytes were prepared by employing electrospun mats based on a blend of poly (ethylene oxide) [PEO]/poly (acrylonitrile) [PAN]/graphene nanocomposites. The effects of dispersion of graphene oxide (GO) and graphene sheets (GS) on the morphology, structure, miscibility, thermal, and mechanical properties of the PEO/PAN fibrous mats were investigated. The resultant porous membranes are good absorbent of the liquid electrolyte and exhibit high ionic conductivity. Fourier transform infrared (FTIR) spectra, dynamic mechanical analysis (DMTA), and transmission electron microscopy (TEM), revealed a phase separated structure for all the samples. Furthermore, the theoretical prediction of the position of nanofillers showed that GO particles selectively located in the PEO phase, whereas GS had a tendency to place at the interface of the two phases. Results of wide-angle x-ray scattering (WAXS) and differential scanning calorimetry (DSC) experiments indicated that GS-loaded sample presents lower amount of crystallinity than PEO/PAN and PEO/PAN/GO. Apart from more amorphous nature, GS-containing mat showed more electrical conductivity which resulted in higher ionic conductivity as compared to the other samples. On the other hand, according to TEM and XRD results, uniformly distribution and exfoliation of GO nanosheets into PEO/PAN, led to a profound improvement of the mechanical properties in comparison with PEO/PAN/GS. POLYM. COMPOS., 39:3626-3635, 2018. (c) 2017 Society of Plastics Engineers