Impact of Gamma Irradiation on the Structural, Optical, Chemical and Mechanical Properties of Pet Plastic Waste

Abstract

In this study, the effects of γ-irradiation on the structural, chemical, optical, and mechanical properties of polyethylene terephthalate (PET) plastic waste were investigated with particular relevance to its potential reuse in plastic film and sheeting applications. Industrial post-consumer PET bottle waste was processed and irradiated over an absorbed dose range of 0–1.5 MGy. FTIR analysis indicated modifications in carbonyl and ether groups, suggesting radiation-induced chain scission processes that influence film-forming capability. UV–Vis spectroscopy demonstrated a dose-dependent increase in absorbance, attributed to the formation of chromophoric groups, which may affect optical clarity and light transmission properties of PET films. EPR measurements confirmed the formation of radiation-induced free radicals, influencing the stability and long-term performance of processed films.Mechanical analysis showed an increase in Young’s modulus along with a decrease in elongation at break, indicating a transition from ductile to brittle behavior, which is critical for determining the suitability of irradiated PET in film and sheeting applications.Overall, the results suggest that γ-irradiation can be used as a controlled modification technique to tailor the structure and properties of recycled PET for potential application in plastic film and sheeting materials, contributing to sustainable plastic waste management.