Original diols from sunflower and ricin oils: Synthesis, characterization, and use as polyurethane building blocks
Résumé
A series of novel fatty acid-based diols were designed and synthesized from sunflower and ricin oils using optimized chemical reactions and purifications. These diols were categorized in two different types: (i) fatty acid-based monoester containing diols (FAmE-1 to FAmE-6) and (ii) fatty acid-based diester containing diols (FAdE-1 to FAdE-8). Their synthesis involved a series of reactions such as transesterification, epoxidation, ring opening of epoxide, and thiol-ene additions. Analyses of these new fatty acid-based diols were performed by HPLC/GC and NMR spectroscopy. The latter were then demonstrated as polyurethane (PU) precursors in the bulk polymerization with isophorone diisocyanate in the presence of dibutyl tin dilaurate as a catalyst. The effects of the diol nature and purity on the PU synthesis and properties were investigated. The structural characterization of the different PUs was carried out by means of FTIR, 1H NMR, and 1H DOSY NMR spectroscopy. The thermomechanical and rheological properties of these new PUs were found dependent on the chemical structure and purity of the diol building block. (C) 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012