Author(s)

Naullage I. Perera, Manik Pavan Maheswaram, Dhruthiman Mantheni, Dhanuja D. Perera, M. Ellen Matthews, Alan Riga, Tobili Sam Yellowe

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Three electrorheological fluids (ERFs) of recently synthesized Polyaniline.HCl and Cellulose fluids as well as a commercial product from Fludicon® (Germany), were evaluated with a two-electrode probe unit and by Dielectric Analysis (DEA). The study was a part of an ongoing medical device development project. The dielectric response times were calculated using the critical peak frequency in a corresponding Debye plot of Tan Delta (loss factor/permittivity) vs. log frequency. The DEA revealed the response times (tau, τ) in ms. The Fludicon® ERF was DEA durable (repeat cycles produced same results) and the τ was temperature dependent: 16 ms at 25°C and 0.16 ms at 80°C. The Cellulose ERF was somewhat DEA durable and the τ was 5.5 ms at 25°C and 0.21 ms at 80°C. The response times were logarithmic with the temperature (°C) with a correlation coefficient of >0.98 for the Cellulose and Fludicon® ERFs. The Polyaniline ERF had a τ of 53 ms at 25°C in the 1^st DEA run and there was no indication of a τ for the remaining DEA tests.

ERF, Tan Delta, DEA, Fibrillation, Debye Plot, Response Time

N. Perera, M. Maheswaram, D. Mantheni, D. Perera, M. Matthews, A. Riga and T. Yellowe, "Dielectric Analysis of Response Time in Electrorheological Fluids Developed for Medical Devices," American Journal of Analytical Chemistry, Vol. 2 No. 2, 2011, pp. 85-92. doi: 10.4236/ajac.2011.22009.