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Advanced polymers with high energy density and high efficiency are urgently needed in pulse power capacitor applications. Here, we present a practical design approach towards all-organic polymers with high energy density and high efficiency by enhancing dipolar polarization at the molecular level. Flexible segments were introduced into the backbones of rigid polar aromatic polymers to increase the flexibility of dipoles. Dielectric spectroscopy measurements of designed polymers revealed multiple strong sub-glass transition (sub- T g ) relaxation peaks with low activation energies, which indicated the enhanced movement freedom of dipoles below the glass transition temperature. As a result, dielectric constants were increased up to 46% when compared with their base polymers and D – E loop measurements showed that all these designed polymers had high energy densities above 11 J cm −3 with efficiencies above 90%. These results unveiled a novel approach towards high dielectric constant organic polymers for electrical energy storage.
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High‐Temperature and High‐Energy‐Density Dipolar Glass Polymers Based on Sulfonylated Poly(2,6‐dimethyl‐1,4‐phenylene oxide)
Abstract A new class of high‐temperature dipolar polymers based on sulfonylated poly(2,6‐dimethyl‐1,4‐phenylene oxide) (SO2‐PPO) was synthesized by post‐polymer functionalization. Owing to the efficient rotation of highly polar methylsulfonyl side groups below the glass transition temperature (Tg≈220 °C), the dipolar polarization of these SO2‐PPOs was enhanced, and thus the dielectric constant was high. Consequently, the discharge energy density reached up to 22 J cm−3. Owing to its highTg , the SO2‐PPO25sample also exhibited a low dielectric loss. For example, the dissipation factor (tan δ) was 0.003, and the discharge efficiency at 800 MV m−1was 92 %. Therefore, these dipolar glass polymers are promising for high‐temperature, high‐energy‐density, and low‐loss electrical energy storage applications.
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- Award ID(s):
- 1708990
- PAR ID:
- 10049643
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 57
- Issue:
- 6
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 1528-1531
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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