Poly(lactic acid) (PLA)-rich poly(lactic acid)/poly(e-caprolactone) (PLA/PCL) blends were melt-blended at different compositions. The compositions such as 90/10 and 80/20 were obtained using three different blending methods and processed by injection molding and hot pressing. All blends were immiscible. The crystallinity of PLA increased slightly in the presence of poly(ecaprolactone) (PCL), and the PCL exhibited fractionated crystallization in the presence of PLA. Injection molded specimens, compared with hot pressed specimens, presented much smaller PCL particles regardless of the blending method used. Some interfacial adhesion was observed in all cases. The stiffness of PLA/PCL blends decreased as the PCL content was increased and was independent of processing. Injection molded specimens showed ductile behavior and broke at elongation values close to 140%, while the elongation at break of the hot pressed specimens was clearly lower, most likely due to the larger size of the PCL particles. Although the impact strength of the blends remained low, it improved by approximately 200% with 30% PCL and by 350% with 40% PCL. V C 2015Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42641.

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Poly(lactic acid)/poly(ɛ‐caprolactone)/carbon nanotube (PLA/PCL/CNT) nanocomposites (NCs) were melt‐processed in a conventional industrial‐like twin‐screw extruder maintaining a constant PLA/PCL 80/20 wt. ratio. CNTs located in the thermodynamically favored PCL phase and, as a result, the “sea–island” morphology of the unfilled blend was replaced by a more continuous PCL dispersed phase in the ternary NCs. Rheological and electrical percolation took place at the same CNT contents (over 1.2 wt %) that TEM images suggest continuity of the PCL phase. The electrical and the low‐strain mechanical behaviors upon CNT addition were similar in the reference binary PLA/CNT and ternary PLA/PCL/CNT NCs. In the percolated NCs, the conductivity became 106–107 times higher than in the insulating compositions, while the Young modulus increased linearly upon the addition of CNT (12% increase at 4.9 wt % loading). Moreover, all the PLA/PCL/CNT NCs showed a ductile behavior (elongation at break >130%) similar to that of the unfilled PLA/PCL blend (140%), in contrast to the brittle behavior of binary PLA/CNT NCs. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45265.

Poly(lactic acid)/poly(e-caprolactone)/organically modified montmorillonite (PLA/PCL/OMMT) nanocomposites were melt-processed in a twin-screw extruder under high shear conditions. As a result of the processing conditions employed, the OMMT layers located in the less compatible PCL phase in all the ternary nanocomposites. The morphology of the PLA/PCL blend evolved from "sea-island" to co-continuous upon the addition of OMMT. Both the X-ray diffraction (XRD) and viscoelastic characterization suggested similar OMMT dispersion in the reference PLA binary and in the PLA/PCL ternary nanocomposites, regardless of its location in the PLA and PCL phase, respectively. The reinforcing effect of the organoclay was also similar. The addition of OMMT to the PLA/PCL blend fully compensated the loss in stiffness and oxygen barrier performance produced by PCL in PLA; the nanocomposite with 3% OMMT showed the same modulus and permeability values as those of pure PLA. Moreover, the ductile behavior (elongation at break > 80%) of the PLA/PCL blend remained constant even in the nanocomposite containing 5% OMMT. V C 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43815.