Morphological, rheological, and mechanical properties of PLA/TPU/nanoclay blends compatibilized with epoxy‐based Joncryl chain extender

This study investigates the synergistic effects of Cloisite 30B nanoclay and epoxy-based Joncryl chain extender on the morphological, rheological, and mechanical properties of PLA/TPU blends. Blends of PLA and 25 wt% TPU were melt compounded with nanoclay at various contents of 1, 3, and 5 wt% with and without 0.5 wt% Joncryl. Transmission and scanning electron microscopy analyses confirmed the interfacial localization of nanoclay. While the presence of nanoclay at the interface refined the droplet morphology, the incorporation of chain extender further decreased the TPU droplet size. Such interfacial localization of clay and its excessive dispersion within PLA as well as the refinement of droplets improved the melt viscoelastic properties of the blends specifically at low frequencies. The addition of chain extender also improved the impact strength and ductility of the blends, although the nanoclay incorporation suppressed these characteristics. The addition of nanoclay, however, enhanced the strength and modulus of the blend systems.