Effect of Polymer Structure on Compatibility, Thermal and Rheological Properties of Poly (Ethylene Terephthalate)/Poly (Lactic Acid) Blend

Different blends based on PLA, PET and glycol modified PET (PETG) were prepared by melt blending. The effect of PLA modification via long chain branching and Ti(OBu)4 as catalyst were studied. Melt blending was performed in a discontinuous internal mixer and the compatibility, thermal and rheological properties of blends were investigated. SEM was used to study morphology differences of the samples. Their compatibility was surveyed by rheological tests and FTIR. Thermal properties of blends were studied through DSC, DMTA and TGA. A fine morphology was found for modified PLA/PET blend. The use of catalyst led to better dispersion of PLA through transesterification. The viscosity ratio of different components was the key parameter affecting final blend morphology