Asymmetric and symmetric aromatic triol isomers were synthesized from erucic acid. The pure asymmetric and symmetric triols were crosslinked with MDI into their corresponding polyurethane sheets. The physico-chemical properties of these polyurethanes were studied by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), thermogravimetric analysis coupled with Fourier transform infrared (TGA-FTIR) spectroscopy, and tensile analysis. The A-PU and S-PU demonstrated differences in their glass transition temperatures (T-g) and crosslinking densities. The difference in T-g of these polyurethanes could be explained by the differences in crosslinking densities, which could be related to the increase in steric hindrance, to the crosslinking MDI molecules, between adjacent hydroxyl groups of the asymmetric triol monomers. Overall, it was found that both polyurethanes had similar mechanical and thermal properties. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 117: 3196-3203, 2010