PHOTOEFFECTS ON ELECTRORHEOLOGICAL PROPERTIES OF TIO2 PARTICLE SUSPENSIONS

The electrorheological (ER) effect of TiO2/silicone oil fluids was inv estigated under illumination. Two types of commercial TiO2 powders sho wed opposite photoeffects on the ER properties. While the photoinduced increase in the ER effect for the first type arises from the polariza tion of photogenerated charges, the decrease in the effect of the latt er type appears to be due to photoelectrophoresis, which may be facili tated by effects associated with the large surface area and high water content.