Metathesized palm oil: Fractionation strategies for improving functional properties of lipid-based polyols and derived polyurethane foams

Palm oil metathesized triacylglycerol (PMTAG), the product of 1-butene cross-metathesis of palm oil stripped from it olefins, was fractionated using dry and solvent mediated crystallization. The fractionation yielded solid and liquid fractions (LF-PMTAG and SF-PMTAG, respectively) reminiscent of the stearin and olein portions of the natural palm oil. The polyol which was synthesized from LF-PMTAG (LF-Polyol) comprised similar to 30% more hydroxyl groups (diols, tetrols and hexols) and more short chain moieties than the polyol from SF-PMTAG (SF-Polyol). As a result, LF-Polyol presented a much higher OH value (184 mg KOH/g) than SF-Polyol (136 mg KOH/g) and more advantageous thermal and viscosity properties than SF-Polyol. The LF-Polyol was demonstrated to make improved rigid and flexible foams compared the polyol from PMTAG (PMTAG-Polyol) or from the natural palm oil. The rigid foam (RF) obtained with LF-Polyol presented compressive strength which was 1.5 times higher than the RF prepared with PMTAG-Polyol, indicating that the removal of stearin-like components can significantly increase the rigidity. The study demonstrate that controlled fractionation of PMTAG can produce customized functional feedstocks for enhanced polyurethane foams. (C) 2016 Elsevier B.V. All rights reserved.