VEGETABLE OIL-BASED TRIOLS FROM HYDROFORMYLATED FATTY ACIDS AND POLYURETHANE ELASTOMERS

Novel bio-based polyols were prepared from hydroformylated oleic acid (9-hydroxymethyl-octadecanoic acid) methyl esters and trimethylol propane by transesterification. Hydroformylation produces primary hydroxyls, which allow relatively lower transesterification temperatures and better yields than hydroxy- fatty acids with secondary OH groups. These non-crystallizing polyols (HFME) have no double bonds and their viscosities are acceptable. Polyurethane elastomers prepared by reacting these polyols with diphenylmethane diisocyanate (MDI) had glass transitions temperatures from -33 to -56 oC, depending on the molecular weight of the triols. Tensile strength and Shore A hardness were higher and elongation, swelling and sol fraction lower than those of corresponding networks from polyricinoleic polyols. The plasticizing effect of longer dangling chains in HFME-based polyurethanes were matched to a certain degree by the presence of double bonds in the polyricinoleic polyols, effectively resulting in similar glass transitions.