Biodegradable polymer films: processability, technological properties and their viability for flexible packaging applications

Nowadays, there is a rising interest in the packaging industry regarding more environment-friendly (i.e. biodegradable and/or compostable) polymer-based solutions, especially for film blowing applications. However, replacing traditional, fossil resource-based polymers typically used for such applications is not an easy task, since the more environment-friendly solutions must have adequate features in terms of processability and final properties. In this work, three commercial biodegradable (and, at least partially, biobased) polymers were investigated by a preliminary rheological and mechanical analysis, in order to perform film manufacturing experiments in laboratory equipment. Furthermore, oxygen and water vapour barrier properties were studied by permeability measurements. The investigation was ultimately performed on films produced in industrial equipment, and the results were compared to those for a typical, standard polypropylene (PP) film used in flexible packaging applications. It was found that the mechanical properties were adequate (in some cases, even up to 25–30% higher than for the PP counterpart), as well as oxygen permeability. On the other hand, water permeability was significantly higher than that of PP films, and this should be taken into account in cases where high water vapour barrier properties are required. © 2024 Society of Industrial Chemistry.