Environmental impact reduction of food packaging plastics: from the exploitation of non-renewable resources to microplastics

The exploitation of plastic, especially in packaging, has raised growing concerns due to the poor management of plastic waste, leading to environmental contamination. In recent years, bio-based polymers as substitutes for fossil-based polymers are undergoing a phase of growing academic and industrial interest driven by environmental reasons and the expected depletion of crude oil. In this context, this work aims to contribute to the development of a pathway from bio-based building-blocks to new multifunctional polymeric materials. In particular, the present research work described thus concerns the synthesis, characterization and study of the different properties of bio-based materials based on polyfuran. In detail, poly(butylene furanoate) (PBF) and poly(pentamethylene furanoate) PPeF were synthetized and characterized. The welding behavior of amorphous and semi-crystalline PBF films was studied by means of thermal and ultrasonic welding. PBF can be considered an encouraging bio-based alternative for monomaterial packaging with promising sealing properties. Moreover, PPeF was successfully coated on paper obtaining a coating thickness around 20 µm. The study results are a promising starting point to develop novel multilayer materials that can enter the paper recycling stream. Plastic containers and packaging materials can degrade under different conditions, leading to microplastic formation, which can contaminate food during production processes. Despite the concerning implications, there is a lack of comprehensive research on global trends in microplastic contamination of food and beverages. To fill this gap, the presented work aims to contribute by developing methods for detecting microplastics in plastic-packaged foods. This study includes three main case studies: commercial vegetable oils, coffee capsules and chocolate bars. Different membranes (silicon filter and Anodisc) for the collection of the microplastics and the analysis via µ-FTIR and µ-Raman were tested. The present study could contribute to further increase knowledge of microplastics presence in the human diet.