This is a density functional theory (DFT)-based (M06) study on the polyurethane formation from 1,6-hexamethylenediisocyanate (1,6-HDI) reacting with the monoacylglycerol obtained from the babassu oil. As the lauric acid is the most abundant fatty acid in the vegetable oil, the 2-monolaurin was chosen to scrutinize the polyurethane formation. An analysis of two different mechanisms (stepwise and concerted) showed the concerted pathway as the most favorable, which involves the transference of the hydrogen in the 2-monolaurin to a nitrogen atom in the 1,6-HDI. Finally, the dimerization process takes place by coupling of urethane blocks, instead of growing the chain by adding 1,6-HDI after 2-monolaurin (or vice versa).
Keywords:
DFT; polyurethanes; babassu oil; 1,6-HDI
