Phase-Separated PVDF/Vitrimer Blends with Enhanced Mechanical and Chemical Stabilities Obtained by Reactive Processing

Reactive blending of a vitrimer phase within a thermoplastic matrix offers promising perspectives for the high-throughput synthesis and (re)processing of vitrimer materials using conventional equipment of the plastic industry. Herein, we report on blends between a poly(vinylidene fluoride) (PVDF) matrix with commercially available epoxy/acid vitrimer precursors at fractions ranging from 24 to 75 vol %. The formulation required to obtain a satisfactory dispersion is rationalized with a particular emphasis on the synthesis of a tailor-made poly(methyl methacrylate- co -glycidyl methacrylate) copolymer acting as a compatibilizer at the PVDF/vitrimer interphase. While formulations incorporating intermediate amounts of vitrimer (50–60 vol %) display remarkable toughness well beyond those of the pure components, higher vitrimer fractions (>75 vol %) are required to form a bicontinuous morphology where both PVDF and vitrimer form percolating networks, thus improving the solvent resistance and the high temperature dimensional stability, respectively.