Stéphanie Sanjuan (Aimplas)
5 oct. 2023
Over the last months, the first task of the WP3, related to the mapping and selection of reusable materials has been carried out, where several meetings and research has allowed to the technological leaders of the WP3 (IPC, TUS and AIMPLAS) to select materials, of both petroleum and bio-based polymers, taking into account the requirements of each specific use cases:
VYTAL, with rigid take-away food trays,
ASEVI and SMURFIT KAPPA with Rigid refill bottles,
AUSOLAN with semi-rigid catering trays,
DAWN MEATS with semi-rigid skin pack for meat distribution
UZAJE with reusable semi-rigid delicatessen packaging
This selection includes biopolymers such as PLA, as well as recycled polyethylene materials with different content of recycled, and technical recycled materials, such as Tritan or PETG. Due to its food contact and fully recyclable properties, it has also been considered to include polypropylene. Finally, PBT material has been selected based on its use in some reusable packaging application on the basis of a study carried out in this field.After the definition of an ageing and cleaning protocol done by TUS, and performed by Eternity Systems, and the production of specimens by injection moulding in both AIMPLAS and IPC facilities, a series of mechanical and optical tests were performed in order to identify, in a first phase, weaknesses and strengths of the materials under consideration as possible candidates for reusable packaging.AIMPLAS was in charge of realizing flexural, impact and scratch tests whereas IPC has performed dimensional stability, transparency and colour tests.Regarding the materials ageing by microwave, we can conclude that:
All the materials were affected by microwaving in terms of dimensional stability
Best results were obtained for polyesters
Polyolefins undergo a major colour change after ageing
Concerning the other journey, where the samples are refrigerated, the conclusions are as follows:
In general, we observe that best results were obtained as well for polyesters
Polyolefins exhibit poorer dimensional stability and worse colour change.
Depending on the requirements of each use case, it will be necessary to further analyse all the results in a specific way, and, in this respect, more focused tests are foreseen for each use case in order to be able to select the materials for the next task in which functional materials development will be carried out to extend reusability of each use case with the goal of obtaining the first prototypes in the coming months.