Development and Characterization of Normoxic Polyhydroxyethylacrylate (PHEA) Gel Dosimeter using Raman Spectroscopy

Raman spectroscopy are used to characterize the chemical changes in normoxic polyhydroxyethylacrylate gel dosimeter (PHEA) induced by radiation. Irradiations in the low dose region are performed and the polymerizations of PHEA gels are monitored by the observing the changes of Raman shift intensity of the carbon covalent bond of PHEA originated from both monomer and the cross-linker. The variation in peak intensities with absorbed dose was observed. As the dose increase, the peak intensities of covalent bond of carbon in the polymer gels decrease. This point out that the amount of absorbed dose affect the polymerization of polymer gels. As the absorbed dose increase, the polymerizations also increase. Results verify that PHEA gel dosimeters are sensitive even in lower dose region.

Authors:

• Aifa Afirah Rozlan
• Mohamad Suhaimi Jaafar
• Azhar Abdul Rahman

Keywords:

• normoxic polymer gel
• ascorbic acid
• Ramanspectroscopy
• radiation dosimetry.

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