Electrorheological Properties of Polyaniline Suspensions
نویسندگان
چکیده
Polyaniline (PANI) was synthesized via an oxidative coupling polymerization in acid condition and dedoped in ammonium hydroxide solution. Rheological properties of the PANI/silicone oil suspensions were investigated in the oscillatory shear mode to explore the effects of electric field strength, particle concentration, and host fluid viscosity on electrorheological (ER) characteristics. The PANI-based ER fluids exhibit unusual viscoelastic behaviors under an applied electric field and the ER response is enhanced with increasing electric field strength. The dynamic moduli, G’ and G” dramatically increase by 6 orders of magnitude when the electric field strength is increased up to 2 kV/mm. ER response increases with electric field strength, particle concentration and silicone oil viscosity. The sol-gel transition point is determined and found to occur about 50-200 V/mm for the system investigated.
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