Ionic liquids (ILs) were proved to be efficient reaction media for polycondensations that are difficult or impossible to carry out in conventional media. Brønsted acid ionic liquids (BAILs) were used as both reaction media and catalysts for the polyesterification of 12-hydroxydodecanoic acid, of pre-synthesized oligoesters from diacid/diol equimolar mixtures and of 2,2-bis(hydroxymethyl)propanoic acid. The polyesterifications in the BAILs were much more efficient than conventional methods such as those in the bulk. Linear polyesters with a Mw of about 40000 g/mol were obtained after only 5-30 min reaction time at 90-110 °C in the BAILs, instead of several hours at 200 °C in the bulk. Similarly, hyperbranched polyesters of Mw=10000 g/mol were obtained in 1 h at 150 °C in the BAILs, whereas it takes at least 8 h in the bulk. Linear polyethers of long chain aliphatic diols, which are very difficult to synthesize by traditional methods, were obtained by direct polyetherification in BAILs. We also carried out syntheses of polyamides that are difficult or impossible to synthesize by direct polyamidation. We succeeded in obtaining homopolyamides of β-alanine, L-valine and L-isoleucine and copolyamides of 12-aminododecanoic acid and natural α− and β-amino acids in phosphoruscontaining ILs, in the presence of triphenylphosphite as condensing agent.
