On the Mechanism of Electron Beam Radiation-Induced Modification of Poly(lactic acid) for Applications in Biodegradable Food Packaging

Poly(lactic acid) (PLA) is a biodegradable polymer used for food packaging. The effects of electron beam radiation on the chemical and physical properties amorphous PLA were studied. In this study, amorphous, racemic was irradiated at doses 5, 10, 15, 20 kGy in absence oxygen. Utilizing paramagnetic resonance spectrometry, it found that alkoxyl radicals are initially formed as result C-O-C bond scissions backbone PLA. dominant mechanism determined to be H-abstraction by form C-centered radicals. undergo subsequent peroxidation reaction with gel permeation chromatography (GPC) results indicate reduction molecular mass. differential scanning calorimetry X-ray diffraction showed subtle increase crystallinity Water vapor transmission rates unaffected irradiation. conclusion, these support suitable material applications irradiation packaging, including sterilization biodegradation.