Preparation and electrorheological properties of montmorillonite/titania composite

A new kind of montmorillonite/titania (MMT/TiO2) composite particles is synthesized by means of sol-gel technique for use in electrorheological (ER) active materials. FT-IR, XRD and SEM measurements show that titania is deposited on the surface of montmorillonite particles as anatase nanocrystallites. The MMT/TiO2 composites are used as ER fluid by dispersing them in silicone oil. It is found that the MMT/TiO2 ER fluid has a notable ER effect under DC electric field. When 3 kV/mm electric field is applied, the static yield stress of typical MMT/22.7 wt% TiO2 ER fluid ( phi = 25%) is about 8.3 kPa, which is 4 times of that of pure MMT ER fluid. Furthermore, it is demonstrated that the TiO2 coating content has an important influence on the ER effect.