One-Pot Two-Step Synthesis of Hydroxymethylated Unsaturated VHOSO and Its Application to the Synthesis of Biobased Polyurethanes

A one-pot two-step procedure is developed to catalytically convert very high-oleic sunflower oil (VHOSO) into hydroxymethylated unsaturated derivatives featuring both primary alcohols and carbon-carbon double bonds. The degree of functionalization in alcohols and C=C double bonds can be accurately controlled affording low and high substituted hydroxymethylated VHOSO. The key point to achieve such control is to partly hydroformylate the C=C bonds at 80 degrees C and to subsequently reduce the reaction temperature to 20 degrees C to selectively reduce the aldehydes, while keeping a high CO/H-2 pressure. Step-growth polymerization of highly substituted hydroxymethylated VHOSO with cyclohexyl isocyanate or 4,4MODIFIER LETTER PRIME-methylenebis(cyclohexyl isocyanate) furnishes biobased polyurethanes with improved thermal stability compared to similar polyurethanes synthesized from castor oil. Practical Applications: This study highlights the implementation of triglycerides featuring both C=C double bonds and hydroxymethyl groups. The synthesis proceeds through a one-pot two-steps procedure that consists of a hydroformylation reaction at 80 degrees C followed by a hydrogenation reaction carried out at room temperature. This simple synthetic procedure is of major interest in a context of an industrial-environmental approach. The high reactivity of the obtained primary alcohols allows the synthesis of bio-PUs, displaying untouched C=C double bonds, which could be further functionalized. This finding is of importance as the obtained bio-PUs can be used in many industrial areas such as foams, elastomers, thermoplastics, thermosets, adhesives, coatings, sealants and fibers.