Synthesis and characterization of hydroxylated oligoamides obtained from renewable resources

Several hydroxylated oligoamides have been synthesized and characterized in order to obtain water soluble compounds with a high affinity for polar materials as wood, paper and natural fibres. The interest for the synthetic procedures is the use of renewable resources as starting compounds. In fact natural compounds or their derivatives, as tartaric acid, D(+)-glucaric acid and α, α-trehaluronic acid, have been used as diacids in the polycondensation reactions. In order to activate the acids, the dimethyl esters have been obtained using modified versions of the procedures reported in literature [1, 2]. The polycondensation reactions between different dimethyl esters and different diamines have been performed in order to obtain oligoamides with different behavior. In fact products with different molecular weight and different hydrophilic/hydrofobic ratio have been obtained using diamines as 1,2-ethylenediamine, 1,6-hexamethylenediamine, 1, 12-diaminododecane, 2,2 ’ –(ethylenedioxy)bis(ethylamine), p-xylylenediamine and several polyamines. Several attempts have been made by changing the reaction parameters (time, temperature, solvent, catalyst). Generally the best conditions for the synthesis have been found using methanol or DMSO as a solvent and triethylamine as a catalyst. All the compounds obtained in this study have been characterized through FT-IR, 1H, 13C NMR spectroscopy and through 2D NMR techniques (gCOSY, gHSQC) . The oligoamides with low molecular Weights have been employed in Wood consolidation. Other different applications for example as additives in the commercial formulations of polymers have been studied. [1] T. A. Houston, B. L. Wilkinson and J. T. Blanchfield, Org. Lett., 6, 2004, 679. [2] D. E. Kiely, L. Chen, US Patent 5 329 044, 1994, Chem. Abstr., I22, 1994, 56785.