High-Efficiency P(VDF-HFP)-Based Nanocomposite Dielectrics: Embedding PP Chain Segments to Offset the Efficiency Penalty of Ceramic Fillers

Poly(vinylidene fluoride) (PVDF)-based ferroelectrics are essential for film capacitors, yet their high dielectric loss and low charge/discharge efficiency caused by ferroelectric hysteresis severely limit practical applications. Linear polypropylene (PP), in contrast, dominates the commercial capacitor market due to its high efficiency and low loss, prompting extensive efforts to combine the advantages of both polymers. However, existing approaches often rely on costly molecular design or complex film-forming processes, conflicting with the demands for low-cost and miniaturized electronic devices. Here, we report a solution-based and scalable strategy that avoids high-temperature melt processing to fabricate a hybrid dielectric film comprising a P(VDF-HFP) matrix, embedded PP chain segments, and core–shell structured BT@SiO2 nanoparticles. Polypropylene chain segments are embedded into the poly(vinylidene fluoride-co-hexafluoropropylene) [P(VDF-HFP)] matrix via solution blending, forming molecularly interpenetrating interfaces that effectively suppress ferroelectric hysteresis. Core–shell structured BT@SiO2 nanoparticles are simultaneously incorporated to further enhance dielectric properties. The resulting P(VDF-HFP)-PP/BT@SiO2 nanocomposite films exhibit a high dielectric constant of 46, a charge/discharge efficiency consistently exceeding 80%, and a maximum energy density of 3.92 J/cm3. Phase-field simulations further reveal that the P(VDF-HFP)-PP/BT@SiO2 architecture with graded dielectric constants mitigates local electric field concentration, accounting for the excellent breakdown performance. Unlike conventional high-temperature melt processing or complex molecular design, this work offers a low-cost and scalable route that avoids high-temperature melt processing to high-performance polymer dielectrics, demonstrating that combining molecular interpenetration with core–shell filler engineering provides a promising pathway for next-generation capacitors.