Biopolymer-based multilayer films with natural coatings for food packaging

摘要

Food packaging made of plastics is specially customized to protect products against environmental influences,such as light,contamination,damage,and micro-organisms.In a joint research project,the Fraunhofer Institute for Microstructure of Materials and Systems IMWS and the technical film producer Polifilm Extrusion GmbH,are working to engineer biopolymer-based films for food packaging.In this project,the specialists relied on chi-tosan coatings to increase the resistance of food to microbiological impacts.Technical films and films for packaging-like those used,for instance,to protect drinking bottles,furniture surfaces,cargo transports,and others-are in great demand in the industry Food packaging primarily uses flexible,transparent film products that must meet multiple requirements:On the one hand,they must exhibit strong mechanical stability for protection during transport.On the other hand,thanks to the introduction of migration barriers,they retain the product's valuable smell and taste as well as its freshness and shelf life.To fulfil all these objectives,multilayer films that combine various material properties are frequently used.Most of these technical films are currently still made of the plastics polyethene(PE),polypropylene(PP),polyethene terephthalate(PET)and polyvinylchloride(PVC).