Call name: FFG-Mobilität der Zukunft
Adhesive bonding is gaining importance as joining method in various industrial sectors, as it enables a promising method for joining different (lightweight) materials. However, beside its merits, adhesive bonding does have challenging aspects, as it complicates recycling or repair, respectively. Currently, debonding is achieved via thermal processes or the introduction of force, which typically result in adherent damage.
Consequently, this proposal addresses “deboning on demand” in order to increase sustainability as well as resource efficiency of bonding processes. Hereby, polymers with covalent adaptable networks, in particular polyurethane-based vitrimers, will be used. Vitrimers are a class of polymers that possess dynamic (i.e. reversible) covalent bonds leading to thermoset-like properties while at the same time to thermoplastic-like (re)processability. Polyurethane-based adhesives are a widespread type of adhesives in the automotive industry, hence polyurethane-based vitrimers are expected to offer high potential in this industrial sector. However, these vitrimers have not been widely investigated as adhesives for the automotive industry. In this research project, polyurethane-based vitrimers will be validated for this area of operation. In particular, their adhesion to materials typical for automotive lightweight design, including hybrid joints, will be studied. Special emphasis will be laid on durability in aging and corrosion tests. Another aspect studied will be the ability to debond on demand, especially after conditioning. As polyurethane-based vitrimers have not been optimized to function as adhesives, the results gained from this project will demonstrate their current limitations and will at the same time provide guidance for further project work, thereby laying the foundations for a reversible, recycling-friendly joining method.