Enhanced electro-responsive electrorheological efficiency of polyethylene oxide-intercalated montmorillonite nanocomposite suspension

Polyethylene oxide (PEO)-salt complex is an important polymer electrolyte-based anhydrous electrorheological (ER) material. However, it is difficult to get PEO-based ER material in particle form owing to the low glass transition temperature. Cross-linking and copolymerization with other polymers are widely used ways to form polyether-salt complex with desired dimensions and stability. However, these ways are relatively complex, and the ionic conductivity of resulting products is also too high for ER application. In this paper, we report a simple way to form PEO-based nanocomposite ER particles by intercalation chemistry with montmorillonite (PEO-MMT) under the help of ethanol solvent. The structure and composition of samples were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetry, and so on. An increase in basal d001-spacings demonstrates successful intercalation of PEO in MMT. The electro-responsive ER effect of PEO-MMT suspension under electric fields was studied. It demonstrated that PEO intercalation not only effectively solved the problem of difficult granulation of PEO ER material but also replaced the absorbed water in the interlayer of MMT and greatly limited the ionic conductivity of MMT. Under electric fields, the suspension of PEO-MMT nanocomposite was found to show significant ER effect, weak current density, and wide working temperature range. A significant interfacial polarization process was observed by dielectric spectra measurement, which can explain the significant ER effect of PEO-MMT nanocomposite.