Compatibility and Thermal Properties of Poly (Ethylene Terephthalate)/Poly (Lactic Acid) Blends

In this study poly(ethylene terephthalate) (PET) and polylactic acid (PLA) were blended and different aspects of the blends were investigated. Melt blending was performed in a discontinuous internal mixer and blends were prepared with different compositions at different processing times. FTIR spectra showed blue shiftingand broadening of identical peaks of polymers which indicates partial compatibility of components. From DSC curves melting point depression could be observed; and DMTA demonstrated decrease in Tgs differences. These two results can confirm compatibility of the blends. Morphology of blends and influence of processing time were investigated by SEM and it was observed that blends formed matrix-droplet structure in which PET droplets have dispersed in PLA matrix