Improvement in Toughness of Poly(ethylene 2,5-furandicarboxylate) by Melt Blending with Bio-based Polyamide11 in the Presence of a Reactive Compatibilizer

The objective of this study was to improve the toughness of bio-based brittle poly(ethylene 2,5-furandicarboxylate) (PEF) by melt blending with bio-based polyamide11 (PA11) in the presence of a reactive multifunctional epoxy compatibilizer (Joncryl ADR (R)-4368). The morphological, thermal, rheological, and mechanical properties of PEF/PA11 blends were investigated. Compared with neat PEF, the toughness of PEF/PA11 blend was not improved in the absence of the reactive compatibilizer due to the poor compatibility between the two polymers. When Joncryl was incorporated into PEF/PA11 blends, the interfacial tension between PEF and PA11 was obviously reduced, reflecting in the fine average particle size and narrow distribution of PA11 dispersed phase as observed by scanning electron microscopy (SEM). The complex viscosities of PEF/PA11 blends with Joncryl were much higher than that of PEF/PA11 blend, which could be ascribed to the formation of graft copolymers through the epoxy groups of Joncryl reacting with the end groups of PEF and PA11 molecular chains. Thus, the compatibility and interfacial adhesion between PEF and PA11 were greatly improved in the presence of Joncryl. The compatibilized PEF/PA11 blend with 1.5 phr Joncryl exhibited significantly improved elongation at break and unnotch impact strength with values of 90.1% and 30.3 kJ/m(2), respectively, compared with those of 3.6% and 3.8 kJ/m(2)for neat PEF, respectively. This work provides an effective approach to improve the toughness of PEF which may expand its widespread application in packaging.