Abstract

Roja K.*, Revathi H., Jeeva K., Saminathan C.

ABSTRACT

The extensive use of polyethylene terephthalate (PET) bottles for packaged drinking water has raised concerns regarding the release of microplastic-derived chemical leachates during environmental exposure and storage. The present study aimed to evaluate the photodegradation kinetics and thermal-induced degradation behavior of PET-derived microplastic leachates using UV–Visible and Fourier Transform Infrared (FTIR) spectroscopy. UV spectroscopic analysis was carried out using terephthalic acid as a reference compound, and the maximum absorbance wavelength (λmax) was identified at 241 nm. Photodegradation studies performed under sunlight exposure which shows progressive reduction in absorbance with increasing exposure time, indicating degradation of aromatic PET-derived compounds. Thermal degradation studies conducted at 40 °C, 60 °C, and 80 °C shows notable structural modifications in PET leachates, as detected45r by FTIR spectral changes in carbonyl, hydroxyl, and ester functional groups. Increased carbonyl index values at elevated temperatures suggested enhanced thermo-oxidative degradation. The findings indicate that environmental stress conditions may accelerate PET degradation and contribute to the formation of microplastic-derived contaminants in packaged drinking water.