Research on the dielectric properties of flexible β-CD/PVDF all-organic films

All-organic dielectric polymers are currently a hot topic in the study of dielectric materials. However, it is still challenging to improve the dielectric constant, breakdown strength, and energy storage density of materials simultaneously. This study used PVDF as the matrix, and β-CD/PVDF all-organic composite dielectric films were prepared using a solution blending method. The research found that after the introduction of β-Cyclodextrin (β-CD), the β-phase content of the polymer and the crystallinity of the films were 40.9 % and 48.96 %, respectively, which are 1.1 and 1.4 times that of pure PVDF. Improved microstructure significantly enhanced the dielectric performance and energy density of the composite films with β-CD. The composite films with β-CD with dielectric constant (ε_r), breakdown strength (E_b), and energy density reaching 12.35, 401.7 MV/m, and 6.11 J/cm³, respectively, which are 1.38, 1.1, and 1.3 times that of pure PVDF. This method provides a new pathway for preparing all-organic dielectric films with high dielectric constant, high breakdown strength, and high energy density.