HMF–glycerol acetals as additives for the debonding of polyurethane adhesives

Diols prepared via solvent-free acetalisation of hydroxymethylfurfural with glycerol were incorporated as additives into polyurethanes based on a bioderived polyether polyol. Moisture-cured as well as acrylate cross-linked films of these PUs were prepared. Both materials displayed excellent thermal stability and could be cleaved in acidic solutions. In particular the highly cross-linked film produced from the acrylate endcapped polyurethanes displayed a clear tuneability of the degradation behaviour according to the amount of acetal additive incorporated. This system has the potential to be used for the selective debonding of polyurethane-based adhesives at the end of their lifetime to facilitate the recycling of expensive components and raw materials from complex devices such as consumer electronics.