Structure and crystallization kinetics of PVDF/organoclay nanocomposites processed by twin-screw extrusion and electrical contact poling

Poly(vinylidene fluoride) (PVDF) is a strongly anisotropic electroactive polymer whose piezoelectric and ferroelectric properties comes from the way dipoles align cooperatively in the polar and crystalline phases. However, producing these phases and controlling their orientation to favor a texturation during melt processing is still a challenge. This study demonstrates a combined approach using a quaternary ammonium-modified montmorillonite (Dellite® 67 G) and high-temperature electrical poling to promote PVDF phase selection and induce microstructural texturation. PVDF nanocomposites containing – clay were prepared via twin-screw extrusion, ensuring reproducible dispersion. Differential scanning calorimetry and polarized optical microscopy show that the organoclay enhances nucleation, helping PVDF to crystallize faster. That heterogeneous crystallization increases the crystallization temperature by up to . WAXD and FTIR analyses reveal that the clay stimulate the formation of polar and phases even at low loadings. A main objective of this work is to investigate the synergy between clay-induced nucleation and electrical-field-induced chain and dipole alignment. Contact poling at maximizes this coupling, yielding electroactive phase content in the nanocomposite, compared with in neat PVDF. This enhancement is attributed to ion-dipole interactions at the clay interfaces and the way the electric field drives PVDF chains into aligned conformations. Overall, this study gives a reproducible melt-processing route that allows control over PVDF’s crystalline phase by exploiting the combined action of nanofillers and electrical poling at elevated-temperature. This approach establishes a foundation for scalable production of highly anisotropic, high-performance electroactive materials for sensing, energy harvesting, and actuation applications. • PVDF-organomodified clay nanocomposites were produced by melt extruding. • The crystallization kinetics of PVDF and its nanocomposites were studied. • The nanocomposite favors crystallization into the electroactive and PVDF phases. • Poling at 75 at 160 leads to electroactive content in the composite. • Hypotheses are suggested to explain the atypical crystallization behavior.