Electrorheological fluids of polypyrrole-tin oxide nanocomposite particles

The electrorheological (ER) response of polypyrrole(PPy)-tin oxide nanocomposite ER fluids increased with the increase in the tin oxide/pyrrole weight ratio, particle volume fraction, and electric field strength. The dielectric properties and direct current (dc) conductivity of PPy-tin oxide nanocomposite particles and the dielectric properties of PPy-tin oxide nanocomposite ER fluids agreed with the ER behaviors. The ER behavior of PPy-tin oxide nanocomposite ER fluids was well fitted to τ = 0.0248ϕE 1.5 and showed a transition from that of the polarization model (τ ∼ E 2) to that of the conduction model (τ ∼ E 1.5) depending on the tin oxide/pyrrole weight ratio.