O. Weichold

European Polymer Congress, 13. Juni 2019, Kreta

Fighting fire with feathers – transforming natural waste into flame-retardant materials

ABSTRACT: Keratin is a natural fibre protein widely found in the animal kingdom, where it is the basis of e. g. wool and hair, horns, scales, and feathers. Besides its broad spectrum of mechanical properties, keratin is particularly characterized by its poor flammability and even self-extinguishing behaviour. Most approaches which use keratin as a chemical feedstock require a solubilisation step, and this can be accomplished by either alkaline hydrolysis or reduction of the disulphide bridges. We have refined the latter to be more convenient and economical, but more importantly to produce two kreatin fractions, which were both found to be valuable intermediates in producing flame-retarding materials. The first fraction consists of water-soluble protein hydrolysates, which can be used as impregnation for particle and fibre boards. The second fraction is a gel, which can be transformed into foamed boards. These materials match commercial EPS/XPS boards in terms of their thermal conductivities, but will not ignite or burn when subjected to an open flame. The contribution will present our latest results on the preparation and application of these two fractions.