Electric Field Generated Stress Moduli in Polythiophene/Polyisoprene Elastomer Blends

The effects of crosslinking ratio and electric field strength on the rheological properties of polyisoprene and polythiophene/polyisoprene (Pth/PI) blendss were investigated as potential electroactive actuator. Electrorheological properties of polyisoprene and blends were measured under the oscillatory shear mode with the applied electric filed strength varying from 0 to 2 kV/mm. The dynamic moduli, G$'$ and G$''$, of the pure polyisoprene depend on the crosslinking ratio and the electric filed strength; the storage modulus (G$'$) increases but the loss modulus (G$''$) decreases with increasing crosslinking ratio. The storage modulus (G$'$) and the loss modulus (G$''$) of the pure polyisoprene fluid exhibit no change with increasing electric field strength. For PI with the crosslinking ratios of 2, 3, 5 and 7 (PI{\_}02, 03, 05 and 07), the storage modulus sensitivity, $\Delta $G'/G'$_{o}$, increases with electric field strength and attains maximum values of 10{\%}, 60{\%}, 25{\%}, and 30{\%} at the electric field strength of 2 kV/mm, respectively. The loss modulus (G$''$) of the PI with the crosslinking ratios of 2 and 3 increases with the electric field, but for the blends of the crosslinking ratios of 5 and 7, it decreases. For the blends of polythiophene with PI at concentrations of 5{\%}, 10{\%} and 20{\%} by vol, G$'$ and G$''$ are generally higher than those of pure polyisoprene.