A radichromic dye of tris-(4-aminophenyl)methane incorporated into polymeric films for radiation dose monitoring

Abstract

With the goal of developing new dyed film dosimeters for radiation technology applications, radiochromic films based on tris(4-aminophenyl)methane, a radiation-sensitive dye, have been studied for dose monitoring in the dose range of 0.5–25 kGy. A chlorine-containing material, hexachloroethane, was incorporated into these films to improve their radiation sensitivity. In addition, a UV-absorber of tinuvin-P were employed to protect these films from the influence of light during storage and measurements. Subjecting these films to γ-irradiation induces a significant magenta color characterized by an absorption band at 553 nm. The intensity of this band increases linearly as the absorbed dose increases up to 25 kGy and 10 kGy for compositions without and with HCE, respectively. The radiation sensitivity of the films incorporating 5.0 phr HCE is ∼2.4 times greater than that of films without HCE. The irradiated dyed films remain stable at 6 °C over two months in the dark. The responses of films are relatively independent of relative humidity in the 53–75% range and temperature in the 8–34 °C range. However, the films’ response is temperature dependent above 34 °C, thus it is advisable to calibrate these films under actual used conditions. The estimated absorbed doses using these films have an uncertainty (2σ) of 6.63%. In conclusion, the prepared dyed films may be good candidates for use as chemical dosimeters or indicators for applications involving radiation processing, such as food irradiation and medical sterilization.