Optical properties of unirradiated and irradiated rhizophora apiculata dyed polyvinyl alcohol solution dosimeter / Hanifah Md Ishak

Radiations have been used for centuries mainly in industrial processing. The technologies in radiation have widely used, therefore it need specific dosimeter system to act as process controller. Rhizophora Apiculata bark crude dye was extracted using 70% aqueous acetone and added into PV A solution. The dosimetry characteristic of Rhizophora Apiculata bark crude dye based PV A solution at different pH with dose of gamma irradiation up to 29 kGy were investigated. From the FTIR spectra, it is found that the intensity of C-OH and C=O stretching vibration decreased with the increased of the dose of gamma radiation. It also found that intensity of C-OH and C=O stretching vibration decreases with increases of pH. The UV-Vis absorbance were found decreased with the increase of gamma irradiation which resulting to a color bleaching of the Rhizophora Apiculata bark crude dye based PV A solution. The most suitable pH that can be used for radiation sensitive dosimeter is pH 12. It is because it responds to pH value changes very drastically with± 9.