Hermann K P, Geworski L, Muth M, Harder D
Phys Med Biol. 1985 Nov;30(11):1195-200. doi: 10.1088/0031-9155/30/11/002.
A water-equivalent plastic material RW-1, in the form of thin foils as well as of thicker sheets, has been produced by melting powdered polyethylene together with CaCO3 and MgO. The mixture has been developed in a three-step procedure, starting with provisional mixtures and using data from their measured attenuation curves to determine the final composition. The attenuation curves of RW-1 and of water, as well as their backscatter factors, are in excellent agreement for x-ray tube voltages from 10 to 100 kV.