Frequency dependence of viscoelastic properties of medical grade silicones

Abstract Cylinders of medical grade silicone elastomers, (29 mm in diameter and 13 mm thick), immersed in physiological saline solution at 37°C, were investigated by dynamic mechanical analysis (DMA). A sinusoidal cyclic compression of 40 ± 5 N was applied over a frequency range, f, of 0.02–100 Hz. Values of the storage, E′, and loss, E″, moduli for the cylinders were found to depend on f; the dependence of E′ or E″ on the logarithm (base 10) of f was represented by a third‐order polynomial. Above about 0.3 Hz, the cylindrical specimens appeared to be undergoing the onset of a transition from the rubbery to the glassy state. There was no significant difference between results obtained at 37 and 23°C; pretreatment of specimens in physiological saline at 37°C for 24 h and 29 days had no appreciable effect on the results. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009