Immiscible Poly(L-lactide)/Poly(e-caprolactone) Blends: Influence of the Addition of a Poly(L-lactide)/poly(oxyethylene) Block Copolymer on Thermal Behaviour an Morphology

A binary PLLA/PCL (70/30 by wt) and ternary (70/30/2) blends, containing a diblock PLLA-PEO or a PLLA-PCL-PLLA triblock copolymer as third components, were obtained by melt extrusion and studied by DSC, POM and SEM techniques. The size of the dispersed PCL domains were strongly reduced in the presence of the copolymer and the emulsifying effect was enhanced with the PLLA-PEO copolymer. The results were analyzed on the basis of the solubility parameters of the blend components