Feasibility of using mixtures of silicone elastomers and silicone oils to model the mechanical behaviour of biological tissues

Mixtures of silicone elastomer and silicone oil were prepared and the values of their Young's moduli, E, determined in compression. The mixtures had volume fractions, phi, of silicone oil in the range of 0-0.73. Measurements were made, under displacement control, for strain rates, (epsilon) over dot, in the range of 0.04-3.85 s(-1). The behaviour of E as a function of phi and (epsilon) over dot was investigated using a response surface model. The effects of the two variables were independent for the silicones used in this investigation. As a result, the dependence of E values (measured in MPa) on phi and (epsilon) over dot (s(-1)) could be represented by E= 0.57 - 0.75 phi + 0.01 log(e)((epsilon)) over dot. This means that these silicones can be mixed to give materials with E values in the range of about 0.02-0.57 MPa, which includes E values for many biological tissues. Thus, the mixtures can be used for making models for training health-care professionals and may be useful in some research applications as model tissues that do not exhibit biological variability.