This work studies phase behavior, microstructure and percolation of the poly(ethylene glycol) (PEG), filled by multiwalled carbon nanotubes (MWCNTs), organo-modified montmorillonite (OMMT), and their mixtures, using differential scanning calorimentry (DSC), X-ray diffraction (XRD), electrical conductivity, and analysis of microscopic images. The DSC and XRD data showed a noticeable decrease of PEG crystallinity with increase of nanofiller content. Filling of PEG by MWCNTs was accompanied by a percolation threshold at ≈0.1 wt%, and the estimated electrical conductivity exponent ( t = 1.77 ± 0.07) was typical for the random percolation networks. The similar threshold behavior, but with higher percolation threshold ≈0.5–1.0 wt%, was observed for PEG filled by OMMT. The observed effect of OMMT-enhanced dispersion of MWCNTS in PEG at a high level of loading by nanoparticles offers good prospects for simultaneous improvement of the electrical and mechanical properties of PEG-based composites.
A new ethanol biosensor based on polyfluorene-g-poly(ethylene glycol) and multiwalled carbon nanotubes