Interface‐Strengthened Polymer Nanocomposites with Reduced Dielectric Relaxation Exhibit High Energy Density at Elevated Temperatures Utilizing a Facile Dual Crosslinked Network

Abstract

High‐temperature ceramic/polymer nanocomposites with large energy density as the reinforcement exhibit great potential for energy storage applications in modern electronic and electrical power systems. Yet, a general drawback is that the increased dielectric constant is usually achieved at the cost of decreased breakdown strength, thus leading to moderate improvement of energy density and even displaying a marked deterioration under high temperatures and high electric fields. Herein, a new strategy is reported to simultaneously improve breakdown strength and discharged energy density by a step‐by‐step, controllable dual crosslinking process, which constructs a strengthened interface as well as reduces molecular chains relaxation under elevated temperatures. Great breakdown strength and discharged energy density is achieved in the dual crosslinked network BT‐BCB@DPAES nanocomposites at elevated temperatures when compared to noninterfacial‐strengthened, BT/DPAES composites, i.e., an enhanced breakdown strength and a discharged energy density of 442 MV m−1 and 3.1 J cm−3, increasing by 66% and 162%, and a stable cyclic performance over 10 000 cycles is demonstrated at 150 °C. Moreover, the enhancement through the synergy of two crosslinked networks is rationalized via a comprehensive phase‐field model for the composites. This work offers a strategy to enhance the electric storage performances of composites at high temperatures.

Based On Confined Polymerization: In Situ Synthesis of PANI/PEEK Composite Film in One‐Step

“…[47,39] Figure 4b shows the relationship between electrical conductivity and PEEKt film thickness at room temperature and 1000 Hz, which shows the conductivity of the 75 μm-PEEK/PANI film reaching the maximum. [69][70][71] As the thickness increases to 75 μm, the aniline on the outside of the film diffuses into the solution, but the aniline on the inside is restricted to the inside of the film due to diffusion hindered, and the formed PANI gradually aggregates into a conductive path, and the conductivity increases. The conductivity of the 75 μm-PANI/PEEK film reaches a maximum of 3.01×10 −4 S m −1 .…”

Effect of organic Na+‐montmorillonite on the dielectric and energy storage properties of polypropylene nanocomposites with polypropylene‐graft‐maleic anhydride as compatibilizer

“…where P is the cumulative probability corresponding to the dielectric breakdown, α is the characteristic breakdown strength of 63.2% failure probability, and β is a shape parameter to evaluate the dispersion of data. 6,45 A linear fit was used to calculate the characteristic E b , and each characteristic curve of this linear fit corresponds to 15 specimens per sample. As shown in Figure 6a, compared with PP, PP/PP-g-MAH blend shows higher breakdown strength, which increases from 327 MV/m of PP to 375 MV/m of PP/PP-g-MAH.…”

In‐situ fabrication of barium titanate@polyvinyl pyrrolidone in polyvinylidene fluoride polymer nanocomposites for dielectric capacitor applications

“…To minimize both, the surface functionalization of the nanofillers becomes essential for homogeneous dispersion and interfacial properties. [5][6][7][8][9] The researchers have used polydopamine (PDA), 10,11 polyurea, 12 fluoropolymers, 13,14 silicon dioxide (SiO 2 ), 15 polyvinylpyrrolidone (PVP), 16,17 and so forth. Besides dielectrics, polymer nanocomposites also have extensive applications in piezoelectrics, triboelectric, biomedical, and food packaging.…”