Table 7.3. Directions For Preparing Simulated Brain Material
For 915 and 2450 MHz (Guy, 1971a; Chou et al., 1984)
  1. Weigh all ingredients and determine percentages by weight.

  2. Mix ingredients except TX-150 in 14-20°C water with a 4-in. shear stirrer rotating at 450 rpm on a variable-speed drill press until all polyethylene powder is wet. Add one drop of household liquid detergent to help wet the polyethylene powder.

  3. Add TX-150 and increase drill press speed to 1200 rpm.

  4. Mix for about 45-120 s. When the mixture becomes thick, slow the drill press to about 800 rpm to avoid generating air bubbles. Since the setting time of TX-150 varies with factory batch, proper water temperature and mixing time must be determined by experience. If stirred too long, the mixture may be filled with air; if not stirred enough, the polyethylene powder will float. The larger amount of polyethylene powder in this mixture makes it more difficult to determine the correct stirring time.

  5. When the mixture looks soupy, pour it into a plastic bag and let it set; then force it into the mold.