Multi-layer structures with aluminum (vapor-deposited or laminated) is one of the most important packaging materials as they protect sensitive foodstuffs against oxygen, water vapor and light while being cost-effective, lightweight, flexible and mechanically stable. However, the combination of different materials presents a potential weak point: ingredients from the packed products such as oils, acids, alcohols can migrate into the laminate over time (migration) and can cause chemical and structural changes within the packaging material. Even low mechanical loads e.g. during transport can weaken the bond and allow corrosion on the aluminum layer. As a result, delamination phenomena of the packaging laminate and migrations of the corrosion products into the food are possible. In order to counteract these processes, it must first be determined which processes contribute to this failure and when the failure occurs. These new findings, which will be gained within this project, should be considered later during the development of a packaging. At the moment, a complex search for more suitable materials or adhesives begins only in the event of damage, which often entails a new development of the packaging.
The aim of the project is therefore to use typical food specific simulants to clarify how chemical reactions in the packaging material affect the mechanical load capacity. Since this is a complex multidisciplinary problem, three of the most important research institutes in the field of plastics research (Leibniz Institute for Polymer Research Dresden eV – IPF), corrosion phenomena (Institute for Corrosion Protection Dresden GmbH – IKS) and packaging development (Fraunhofer Institute for Process Engineering and Packaging – IVV) have joined together as the scientific consortium.
The project will investigate chemical delamination phenomena in aluminum laminate packaging based on theoretical considerations (Phase 1), simplified model systems (Phase 2) and finally market-ready packaging solutions with selected products (Phase 3). The results are decision support systems and databases for the targeted packaging development of chemically active products. The elucidation of the corrosion and damage processes after storage makes it possible to prevent damage and to specifically predict the shelf-life of the packaging solutions. This minimizes the amount of materials used in the laminate by matching the shelf-life of the packaging with the desired shelf-life of the product. The companies involved in the project can bring in concrete cases of damage in phase 3 and thus gain direct benefit from the project results.