Synthesis of new biobased linear poly(ester amide)s

Abstract

In the present work, we investigated the synthesis of new biobased linear aliphatic PEAs with a controlled regicity, in a two steps procedure. First, dioldiamide derivatives were successfully synthesized, then polycondensation reaction using the usual alcohol plus acid reaction was performed. NMR analyses demonstrate that dioldiamide can be synthesized in one step from diacid and ethanolamine condensation with high conversion. A new library of polymers was then synthesized, and characterized. Overall, the reactivity of amine or alcohol or acid functions is investigated by in-depth 1H and 13C NMR versus HSQC NMR analysis. These results can be used to follow the complex evolution of monoesterification or diesterification reactions, monoamidation or diamidation reactions when dicarboxylic acids versus alcohol or amine are reacted. Thermal degradation was examined, and a good stability of all the polymers was evidenced. The thermal properties of the polymers were also analyzed, and high melting temperatures were measured, thanks to the control of the regicity. Comparing the melting and crystallization temperature revealed a fast rate of crystallization, an important feature for polymer melt processing. The solubility behavior of these polymers was found to be close to the one of polyamides, suggesting the use of this new polymers library to replace polyamides in applications where biodegradability of the materials is required.