Anagrafe della ricerca

Plastic packaging has an increasingly negative impact on the environment. In fact, only less than half of the plastic packaging waste generated is recycled in the EU (ca. 40% in 2019). In addition, plastic packaging production strongly relies on fossil sources, while sustainable alternatives may arise from the use of abundant, low cost, renewable, and biodegradable sources. StarLight aims to tackle both the issues by developing an innovative packaging material derived from a renewable agri-food waste such as starch. We expect that this new material can combine the properties of being recycled and/or composted on demand with good performances, competitive with those of plastic polymers currently used. Starch, a natural polymer obtainable from biomass and food waste, is water-sensitive, undergoes physico-chemical degradation at relatively low temperature, and lacks mechanical resistance. While these features are desirable for biodegradation, they hinder applications. Strategies to solve this issue are the addition of inorganic nanofillers and the use of reversible crosslinking processes. Within the project starch and nanofillers, such as 2D natural silicates or titanium dioxide, will be modified with reversibly photocrosslinkable groups. The resulting hybrid nanocomposite is expected to have mechanical performance and barrier to gases suitable for packaging. Key innovative points of StarLight are: i) reversibility of the curing reaction: reversible crosslinking groups introduced both on the starch chains and nanofiller surfaces ensure crosslinking upon irradiation at a given wavelength, and the dismantling of the composite (de-crosslinking) by irradiation at a different wavelength and/or by heating, allowing to re-obtain the prepolymers and the fillers, which can be then either composted or reprocessed/reused; ii) sustainability of the nanocomposite: the design of the material complies with the principles of green chemistry, i.e. the selected crosslinking reactions are eco-friendly, occur at room temperature, without organic solvents and harmful crosslinkers; iii) smart features of the nanocomposites combining mechanical stability, gas barrier, enhancement of the shelf life of the packaged product. The scientific outcomes of the project can open the way to the technological development of a new packaging satisfying the present requests of industry. On a long-term basis, the project may also have an impact on society in terms of packaging waste management. For these reasons, StarLight complies with mission 2 of the “PNRR” by tackling key issues such as circular economy and plastics recycling. Further objective of StarLight is the development of citizen’s awareness on sustainability, and training of young researchers recruited within the project, offering them professional skills useful for future employment in industry. Thus, StarLight also pursues the goals of mission 5 of the “PNRR” by reducing the gaps between research, society and industry.