The Preparation and Characterization of Poly(lactic acid)/Poly(ε-caprolactone) Polymer Blends: The Effect of Bisphenol A Diglycidyl Ether Addition as a Compatibilizer

The problems created by conventional polymers after their end use have driven research into new biodegradable polymeric materials. PLA is a compostable polymer obtained from renewable sources, but its main drawbacks are its fragility and slow crystallization kinetics. These drawbacks limit its use in different applications. In order to overcome fragility, in the current study, different compositions of PLA/PCL blends, rich in PLA content and without and with DGEBA, were prepared and characterized by means of different techniques, such as FTIR, DSC, DMA, and the mechanical properties. Some compositions show a certain improvement in the deformation capacity compared to the neat PLA at a low test speed. However, when the test speed increases, no improvement is observed in terms of deformation capacity. By SEM, the morphology of injection-molded specimens was observed. All blends showed a biphasic morphology where the PCL droplets are dispersed within the continuous PLA matrix. In the current study, an attempt has been made to improve the compatibility and adhesion between the phases by incorporating a diglycidyl bisphenol A compound. The results obtained indicate that the epoxy groups seem to react with the end groups of the PLA chain; however, the interactions that it creates with the PCL phase are weak, which is in agreement with the FTIR and DSC results obtained.