Monitoring the degradation status of biodegradable polymers by assessing thermal properties

International audience

إنجليزي. With the increase of the global population, the demand for plastic materials in every aspect of life and industry has become tremendous, the packaging sector being the first to both use plastics and produce plastic wastes, whose a great part will irremediably end up in both terrestrial and aquatic environments. To face the environmental issues stemming from the accumulation of conventional plastics, biodegradable plastics, whether they derive from renewable feedstocks or petroleum, are seen as promising alternatives. Among the biodegradable plastics suitable for replacing conventional plastics for food packaging applications for instance, several materials based on different polymer and formulations (PBAT, PLA, PHAs, PBS, PBSA, TPS) are currently available for satisfying the functional requirements of a daily use plastic with a lower environmental impact. Despite their promising potential, the development of these alternative solutions has given rise to debates about their performance under real conditions, particularly because of the risk of releasing microplastic residues, the persistence of which remains to be demonstrated. In this context, the present study aims at providing a critical assessment of the main methodological approaches commonly used to monitor the progress of the biodegradation process and evaluate the degradation status of plastic micro-fragments made of biodegradable polymers that could potentially be released into the environment. Amongst the methods highlighting morphological, structural, and chemical modifications induced on the surface and/or in the bulk of the material, measurements of thermal properties have emerged as relevant quantitative descriptors for assessing polymer degradation and predicting their fate in the environment.