This deliverable describes the obtention of multilayer structures at laboratory scale according to the different demonstrators defined in WP2 for DANONE and FERRERO. Very promising oxygen barrier values have been obtained. The scale-up of the different formulations (protein and PHA coating and bio-adhesives) and metallization has also been successfully carried out.
The use of bio-based materials for packaging has drawn attention worldwide in order to minimise the environmental impact of petroleum-based plastics. Great number of studies have focused on the performance improvement of these polymers as a single biopolymer rarely has comparable properties to the fossil ones. To overcome this limitation, multilayer structures are needed where two or more materials are combined to improve the performance of biopolymers. Polysaccharides, proteins and polyhydroxyalkanoates (PHAs) can be used to formulate bio-based functional coatings in order to improve the properties of biopolymers.
The PRESERVE project is in line with what has been mentioned. The main objective is the substitution of fossil fuel-derived plastics for bio-based ones used in food and drink packaging. This confidential deliverable D3.7. describes the upscaling of the different coatings (protein and PHA) and bio-adhesives (polyurethane-based and hot-melt) developed in WP3 and the obtention of multilayer structures in order to get the target properties of the demonstrators defined in WP2 (snack Flowpack, beverage brick, pouch, FFS container for liquid products and moulded pulp Packaging).
The protein coating was successfully scaled-up as well as the metallization process. The 100% solids PHA formulation from CENTEXBEL and the water-based one from AIMPLAS were also upscaled with success. Regarding the bio-based adhesive, 8 Kg were obtained with good functionality, reactivity and bond and seal strength values. Concerning the development of multilayer structures, this deliverable describes their obtention at lab-scale level according to each demonstrator including the characterization of barrier properties. Oxygen barrier values of the order of 10 cm3 /m2 ·d·bar have been obtained for PET and PLA substrates. After metallization these values have decreased considerably to values below 1 cm3 /m2 ·d·bar for PLA and around 2 cm3 /m2 ·d·bar for PET. These values may decrease even more once multilayer laminated structures are characterised.
At pilot plant level, only the protein coating application and the metallization process was performed and is described in this deliverable. The obtention of laminated structures at pilot plant level will be included in D3.8.
This is a confidential deliverable, as such the full deliverable is not available to the public.