Preparation & characterization of polyvinyl alcohol/thymol blue composites gel and films for low radiation dosimetry

Background

Exposure to low radiation has been indispensable due to it is necessity in radiography and it is induced potential effects in patients and radiology staff. Hence the measurement and detection became inevitable for radiation practitioners and the patients. The study aimed to present the synthesis of polyvinyl alcohol gel doped with Thymol Blue dye (PVA/TB) as gel and films for low radiation dosimetry.

Method

The polymer was prepared under controlled parameters (PVA 5%, temperature 80 °C, dopped with 0.01, 0.03, 0.05, 0.07, 0.09 mw of TB). The formed gel and films were irradiated with x-ray as: 0, 2, 4, 6, 8, 10 mGy.

Results

Gel and films showed color quenching from yellow to light yellow as the radiation dose increased, as well as gradual significant (R² = 0.97) reduction in optical density for all concentration (0.01, 0.02–0.09 mw of TB). The UV-spectroscope for (PVA/TB_0.01mw) gel showed absorbance peaks at λ = 435, 326 and 279 nm, that decreased significantly (R² = 0.97) as the radiation dose increases. And XRD for (PVA/TB_{0.01 mw}) reveals the crystallinity of PVA at 2 thetas = 19.5° which increased to 40.5% at 10 mGy. FTIR revealed the chemical bonds with relevant intensities (CH (725.1–781 & 3030 cm⁻¹), C – C (883.2 & 1170.6 cm⁻¹), C – O (1063- 1096 cm⁻¹), CH₂ (1357.6 cm⁻¹ wagging, 2879.2 cm⁻¹ alkyl stretch), C = C (1623.8–1651.5 cm⁻¹), C = O (1681.6–1683.6 cm⁻¹), C – OH (3288 cm⁻¹)) that decreased as the radiation dose increased and new radiogenic bonds at vibrational bands 1063–1096 cm⁻¹ referring to C – O – C of Polysaccharide's pyranose and at 2125.1 cm⁻¹ for C ≡ C alkenyl).

Conclusion

Both forms of PVA/TB films and gel showed feasibility and applicability for radiation detection and measurement.