Synthesis and characterization of renewable polyurethane foams using different biobased polyols from olive oil

Abstract

The overall purpose of this study was to synthesize biobased polyols to replace conventional fossil-based polyols in polyurethane foams (PUF) in a multistep approach based on green chemistry, in order to bring both improved properties and sustainability. Oleochemistry has been largely used for PUFs elaboration, but for as far as we know the use of olive oil to obtain such systems had never been reported. The synthesis of the biobased polyols is based on robust approach based on the epoxidation of the double bonds from olive oil using hydrogen peroxide, followed by the ring opening of the epoxides with acetic acid or ethanol to yield polyols with different chemical structures. The chemical structures were determined and checked by NMR and FTIR. The molar masses, the thermal stability and the viscosity were also evaluated. These biobased polyols were further tested making biobased and flexible PUF (FPUFs), with open cells. In this respect, a conventional and fossil-based polyol was partially replaced by up to 35% of each synthesized biobased polyol, alone or mixed. The structural, morphological, mechanical and thermal properties of the PFUFs obtained from the mixture of the biobased polyols were superior to the ones obtained using a sole biobased polyol. Surprisingly, these biobased foams present higher properties than the conventional and fully fossil-based PUF.