High-k Polymer Nanocomposites Filled with Hyperbranched Phthalocyanine-Coated BaTiO₃ for High-Temperature and Elevated Field Applications

Abstract

Two sets of thermal stable nanocomposites were fabricated by using engineering plastics poly(ether sulfone) (PES) as a matrix and phthalocyanine molecules (CuPc) or hyperbranched phthalocyanine (HCuPc)-coated barium titanate (BT) nanoparticles as fillers for high electric field and high-temperature dielectric applications. By side-by-side comparison, the hyperbranched coating is finely addressed for enhancing the dielectric response and breakdown strength of the composites. Specifically, BT-HCuPc/PES exhibits 40% lower dielectric loss and about 110% larger breakdown strength than BT-CuPc/PES. The addition of hyperbranched phthalocyanine may enhance the compatibility and dispersion of the ceramic fillers in the polymer matrix and reduces the charge carrier between the filler and matrix. Meanwhile, high dielectric constant, high breakdown, and low dielectric loss are well-maintained in the composites filled with hyperbranched phthalocyanine-modified BT from room temperature to 150 °C. The discharged energy density of the composites (20 vol % BT-HCuPc/PES) can reach 2.0 J/cm at 300 MV/m, about 166% of that of the polymer matrix (1.2 J/cm). Our findings on hyperbranched coating structure could be applicable to other ceramic-polymer composites to enhance their dielectric response.

Ternary polymer nanocomposites with concurrently enhanced dielectric constant and breakdown strength for high‐temperature electrostatic capacitors

“…Therefore, U e is highly dependent on both K and E , where E limited by the breakdown strength of dielectrics . To enhance U e , extensive studies have been carried out to improve K by adding high K ceramic fillers such as barium titanate (BT), barium strontium titanate, and copper titanate calcium into polymer matrices . However, the thus‐designed polymer composites typically suffer from large reductions in breakdown strength, which preclude a substantial gain in U e .…”

“…25,26 To enhance U e , extensive studies have been carried out to improve K by adding high K ceramic fillers such as barium titanate (BT), barium strontium titanate, and copper titanate calcium into polymer matrices. [27][28][29][30][31][32] However, the thus-designed polymer composites typically suffer from large reductions in breakdown strength, which preclude a substantial gain in U e . Alternatively, wide-band-gap fillers such as aluminum oxide (Al 2 O 3 ), silicon dioxide (SiO 2 ), and boron nitride (BN) have been utilized to enhance breakdown strength of polymer composites.…”

Fabrication of BaTiO3-Loaded Graphene Nanosheets-Based Polyarylene Ether Nitrile Nanocomposites with Enhanced Dielectric and Crystallization Properties

“…Meanwhile, the mismatch in conductivity between the two phases of GO and ZnPc results in more and more free carriers accumulating at the interface and producing strong interfacial polarization, which further leads to an increase in dielectric constant. Furthermore, it is not hard to find that the dielectric constant of all nanocomposites decreases slightly with the increase of frequency, which is due to the polarization relaxation process [30]. However, when the content of BT@ZnPc-GO-1 nanoparticles was 15%, the change rate of dielectric constant was only 10.9% in the range of 100 Hz to 1 MHz, which suggested that the nanocomposites have a good dielectric constant-frequency stability.…”

Rational Design of Soluble Polyaramid for High‐Efficiency Energy Storage Dielectric Materials at Elevated Temperatures

“…The self‐healing properties of polymer dielectrics and the possibility of mass production are important properties for film capacitor industrial applications, which are generally lacking in conventional composite materials. [ 8,9 ] Designing a polymer material with intrinsically excellent electrical energy storage performance is the most convenient operation to improve capacitor performance. Biaxially oriented polypropylene (BOPP) has been a successful commercial dielectric material for its very low dielectric loss (DL < 0.018%) and excellent breakdown strength.…”