Application of Attenuated Total Reflection - Fourier Transform Infrared spectroscopy to characterize the degradation of littered multilayer food packaging plastics

Abstract

Multilayer packaging is used in food consumables as disposable packs. The Attenuated Total Reflection – Fourier Transform Infrared spectroscopy (ATR-FTIR) spectroscopy is used in detecting defects in manufactured food packs. The consumed food packs like chips, biscuits and chocolates are littered without recycling. This is the first study that focused on the degradation potential of littered multilayer food packaging plastics from a dumpsite. The multilayer polymeric composition of various commercial packs was identified by ATR-FTIR spectroscopy based on the functional groups. The multilayer polymeric composition of a certain brand chips packs (commercial and littered) was similar. It has four polymers with the following sequence, Polypropylene (PP), Low-Density Polyethylene (LDPE), metalized-Polyethylene terephthalate (m-PET) and Linear Low-Density Polyethylene (LLDPE). Polypropylene was the printed layer, LLDPE was the inner food contact layer, whereas LDPE and m-PET were the binding layers of the other polymers in the pack. The degradation potential of littered packs from a dumpsite was characterized by ATR-FTIR spectroscopy. The littered multilayer chips packs (2016b and 2015c) were oxidized among the other packs. It was observed based on the OH group formation in the polyolefins, which states the surface degradation. The ATR-FTIR spectroscopy aided in the characterization of polymer degradation from a littered sample.