Polyurethane foams produced from pyrolysis oil - production and possible application

Rigid polyurethane (PU) foams are widely used for instance in building insulation. Two component systems comprising of a polyol (either polyether- or polyester-polyol) as component A and a diisocyanate as component B are generally applied. Both components are produced from fossil oil resources. The liquid products from fast pyrolysis of biomass, called biooil hereafter, contain a largevariety of organic compounds with -OH functional groups. This gives rise to the idea to substitute the polyol component in PU foams with such biomass based intermediates. Following some exploratory experiments a more systematic study is under way to examine the possibility of such substitution. Biooils derived from woody and herbaceous biomass were produced using a laboratory plant for ablative fast pyrolysis. The biooils were pretreated and samples of PU foams produced with a varying amount of biooil substituting the polyol component. Especially the biooils produced from straw showed good insulation property expressed as low thermal conductivity. The achieved thermal conductivity of 0.0283 W/mK with a substitution degree of 80 % was 8 % lower than for the foams produced from commercial components (0.0308 W/mK). These results show high potential for the application of bio-based intermediates in the building sector. Further investigation on other properties are necessary, but the main requirements for thermal conductivity are already met without optimization of the catalyst/stabilizer system.