ESR dosimetry and radical kinetics of gamma-irradiated propyl gallate

Propyl gallate (PG) is one of the most effective synthetic antioxidant. In the present work, the effects of gamma radiation on powder PG were investigated by Electron Spin Resonance (ESR) spectroscopy. The experimental spectra of irradiated PG were found to be consisted of two different overlapped spectra that originated for different radical species. Structural and kinetic features of the radicals which are responsible for experimental ESR spectrum were explored through the variations of the signal intensity with applied microwave power, variable sample temperature, and high-temperature annealing studies. Activation energies of the radical species were determined using the data derived from annealing studies. The dosimetric potential was also investigated in the range of 0.5–25.0 kGy. It was found that the G value of PG is about 0.35.