Expanded Polystyrene (EPS), Polyurethane (EPU), Polyethylene (EPE) and Polypropylene (EPP) represent the most popular moulded cushion packaging materials applied for transport packaging applications. However, despite of their functionality, the widespread use of these polymer foams of synthetic origin implies considerable environmental concerns because of their non-renewable fossil raw material resources, the use of greenhouse gases, such as C₅H₁₂ and CO₂ as blowing agents, their non-biodegradable and non-compostable nature, the short life of cushion packaging products and the cost-ineffectiveness of their recycling.

With this in mind, bio-based plastics represent an emerging and highly promising solution for protective transport packaging provided that they can be processed in foamed products resulting in adequate functional requirements.

Within this framework, the project idea is to develop a flexible, energy-efficient and environmentally-sustainable manufacturing process enabling the production of biodegradable foamed 3D-shaped packaging originating from renewable raw materials (i.e. starch and water). Within the proposed process, expansion and foaming of the bio-polymer will be driven by pressurized microwave technology, exploiting the inner water content of the material itself to generate vapour.