Life cycle assessment of bio-based, waterborne PU adhesives for fast industrial bonding processes
Aqueous PU dispersion adhesives based on high molecular weight, semi-crystalline polyurethane polymers have long demonstrated their outstanding performance and are a well-established bonding technology in several industrial applications. Due to their thermal activation properties and sharp melting area, these adhesives allow for efficient bonding processes with short bond strength build-up times. State-of-the-art is the use of polyester building blocks from fossil raw material resources to synthesize the base polymers. As the use of biobased raw materials and sustainability is increasingly a factor in public and customer perception, it is also becoming increasingly important in industrial processes and company strategies. For these reasons, a consortium of industrial and research partners is working to develop bio-based solutions for PU dispersion adhesives using significant amounts (> 50 %) of renewable raw materials. Target applications include the automobile, furniture and shoe industries. In order to investigate the environmental performance of the new biobased adhesive, a life cycle assessment is carried out. First results indicate that the carbon footprint of the adhesive can be reduced by more than 25% when comparing the biobased adhesive to fossil-based PU dispersions. This project is supported by the ""Fachagentur Nachwachsende Rohstoffe"" (FNR) on behalf of the German Federal Ministry of Food and Agriculture (BMEL) by decision of the German Bundestag.