Aliphatic polycarbonates and poly(ester carbonate)s from fatty acid derived monomers

Fatty acid derivatives were efficiently used as starting materials for the synthesis of polycarbonates and poly(ester carbonate)s. A novel AB-type self-condensable monomer, ethyl(9-hydroxy-10-methoxyoctadecyl)carbonate (EHMOC) and a dicarbonate monomer, 4-[(ethoxycarbonyl)oxy]butyl-12-[(ethoxycarbonyl)oxy]octadec-9-enoate (EOBEOE) were prepared from oleyl alcohol and ricinoleic acid, respectively. Of these, EHMOC was polymerized by the alcohol–carbonate exchange self-polycondensation approach, while EOBEOE was polycondensed with various biobased diols to give polycarbonates and poly(ester carbonate)s, respectively. The monomers and polymers were well characterized by FTIR and 1H-NMR spectroscopy. The 13C-NMR spectroscopy revealed the formation of randomly distributed sequences in the poly(ester carbonate)s due to the carbonate interchange reaction. An unexpected formation of polyricinoleate was observed and confirmed by NMR and MALDI-TOF spectroscopy. Most of the polymers displayed good thermal stability with the temperature at 10% weight loss in the range 273–325 °C. Due to the presence of aliphatic segments, these materials exhibit very low glass transition temperature.