In-situ synthesis, thermal and mechanical properties of biobased poly(ethylene 2,5-furandicarboxylate)/montmorillonite (PEF/MMT) nanocomposites

Poly(ethylene 2,5-furandicarboxylate) (PEF) is an emerging biobased polyester well-known for high gas barrier properties as well as high tensile modulus and strength , but PEF modification is still desired to improve its crystallization rate, toughness and even strength. In this study, PEF/Montmorillonite (MMT) nanocomposites were in-situ synthesized via melt polycondensation of dimethyl furandicarboxylate and ethylene glycol in the presence of a commercially available organically modified montmorillonite (OMMT), i.e., DK2, a montmorillonite clay modified with octadecyl hydroxyethyl dimethyl ammonium. The structure of nanocomposites was characterized by ATR-FTIR, 1 H NMR, WAXD and TEM, and their thermal and mechanical properties were assessed with DSC, TGA and tensile test. The OMMT was grafted with PEF chains and therefore exfoliated, at least partially, in the PEF matrix with intrinsic viscosity over 0.7 dL/g. With respect to pristine PEF, the nanocomposites containing 2.5 wt% DK2 showed significantly improved melt crystallization, tensile modulus and strength.