Development of radiochromic dosimeters based on polyvinyl chloride films containing leuco crystal violet

Abstract

We fabricated polyvinyl chloride (PVC) films containing leuco crystal violet (LCV) to develop a radiochromic material with high sensitivity to radiation. For comparison, polyvinyl butyral, polystyrene, and poly(methyl methacrylate) films containing LCV were additionally prepared. The absorption spectra of these films before and after X-ray irradiation were measured. The change in the absorbance of the PVC film at 600 nm was 2.9-32 times those of other films at a radiation dose of 4 kGy. This result suggested that the generation of crystal violet (CV + ) proceeded efficiently by radicals generated from PVC. The addition of 1 wt% trichloroacetic acid (TCA) to a PVC film containing LCV increased the change in absorbance 1.2 times. This result suggested that the radicals generated by the decomposition of TCA induced the generation of CV + . The sensitivity to radiation of the film was 4.2-28 times greater than those of conventional plastics containing leuco dyes.

Development of radiochromic dosimeters based on polyvinyl chloride films containing 2′-anilino-6′-di-n-pentylamino-3′-methylfluoran (Black305)

“…The change in absorbance of the film containing 0.5 wt% TCA is almost the same as that of the film without TCA, and the absorbance of the film containing 1 wt% TCA is smaller than that of the film without TCA, in contrast to our previous study on LCV. 20) Table I shows the changes in the absorbance of plastic films containing leuco dyes in this study and previous reports. [20][21][22][23][24]31) We compared the sensitivity, as indicated by the change in absorbance/thickness [mm −1 ] per unit dose [kGy −1 ] at the largest absorption peak.…”

“…20) Table I shows the changes in the absorbance of plastic films containing leuco dyes in this study and previous reports. [20][21][22][23][24]31) We compared the sensitivity, as indicated by the change in absorbance/thickness [mm −1 ] per unit dose [kGy −1 ] at the largest absorption peak. The sensitivity of PVC containing Black305 was 11 mm −1 • kGy −1 at 600 nm.…”

“…We have developed radiochromic plastics, 10,20) and Table II shows the lower limit of detection of these materials and of PVC containing Black305. In this table, the lower limit of detection is estimated from the absorbance integrated over a certain wavelength range.…”

“…In addition, the effect of the addition of trichloroacetic acid (TCA) was investigated; in a previous study on the radiochromism of PVC containing LCV, it was reported to enhance sensitivity via the production of alkyl and chlorine radicals upon irradiation. 20)…”

1,10-Bis(diphenylamino)-4,6-decadiyne as an active component of a radiochromic film dosimeter

“…Absorbed doses used in such processes span a wide range going from a few tens of grays to over 100 kGy (ISO/ASTM, 2013). Thus, manufacturing dosimeters in the form of films (Chu et al, 1990;Kawamura et al, 2020;Soliman et al, 2016) or gels (Baldock et al, 2010;Basfar et al, 2019;El Gohary et al, 2016;Koeva et al, 2008;Soliman et al, 2017;Sun et al, 2016) that can accurately measure absorbed doses is an important endeavor.…”