Melting behavior of compression molded poly(ester amide) from 2,5-furandicarboxylic acid

EA 46 is a biobased polymer with promising properties for sustainable packaging applications, which can be obtained via polymerization of a furan 2,5-dicarboxylic acid (2,5-FDCA) derivative and a diol monomer containing internal amide bonds (46 amido diol). In the literature, PEA 46 showed a complex series of thermal transitions during DSC scans. For this reason, in this initial exploratory study PEA 46 was subjected to compression molding and the melting behavior of film samples was investigated with parallel DSC and WAXS analyses. At room temperature, a mesomorph phase was the only one observed. Subjecting the samples to heating scans led to the formation of phase α, caused by a sequence of partially overlapping melting and recrystallization phenomena. An additional melting and recrystallization phenomenon resulted in the development of a phase β, which melted at approximately 173 °C, the temperature after which the material was completely amorphous and isotropic. Phase α could be enhanced via thermal annealing, whereas phase β could be enhanced via a melt crystallization treatment.