Synthesis and characterization of poly(ester amide amide)s of different alkylene chain lengths

In this work, a series of aliphatic biodegradable poly(ester amide amide) polymers was synthesized by melt polycondensation of a tailor-made amide-containing monomer based on 1,4-diaminobutane and e-caprolactone and different dicarboxylic acid methyl esters with even number of methylene groups. The synthesized polymers were characterized by 1H NMR, FT-IR spectroscopy, GPC, SAXS and WAXS. DSC results show that the melting point is located at about 150 °C for all polymers. X-ray scattering experiments in small and wide angles reveal formation of crystals with extended-chain conformation resulting in strict periodicity of electron density along the main chain. TGA data indicate the high thermal stability of polymers to temperatures above 350 °C, which are much above the melting point. The obtained characteristics of the newly synthesized PEAAs can open new perspectives for melt processing to fabricate films, highly oriented fibers and injection-molded parts with good thermal stability and mechanical performance.