Biobased Polymer\nRecycling: A Comprehensive Dive into\nthe Recycling Process of PLA and Its Decontamination Efficacy

The recycling process and the presence of contaminants\nplay important\nroles in alimentary security. In this research, poly(lactic acid)\n(PLA) samples were contaminated using an FDA-defined framework by\nimmersing them in a cocktail of five surrogates (benzophenone, tetracosane,\nheptane, chloroform, and toluene). Migration tests were then conducted\non the samples after different recycling stages by using two food\nsimulants and varying conditions. To this end, it was used SPME–GC–MS\nand GC–MS techniques in order to evaluate the efficiency of\nthe recycling technology. The contaminants in PLA samples decreased\nafter they were submitted to the total recycling cycle. Compounds\nsuch as tetracosane, heptane, and toluene showed decreased values\nbetween 73 and 80%, much higher than those obtained when the sample\nwent through only washing or mechanical recycling. The theoretical\nmolecular volume of contaminants, the type of food simulants, the\ntemperature of the test, and the interactions between the polymer\nand surrogates influence the input and output of contaminants. The\ninteraction energy values estimated from electronic structure calculations\nprove to be useful for predicting and analyzing global interaction\ntrends between contaminants and the polymer. Consistency was observed\nbetween the results obtained from the Hansen sphere analysis and the\ntheoretical approach.