Flexible high-temperature dielectric materials from polymer nanocomposites

Area of Science:

• Materials Science
• Polymer Science
• Nanotechnology

Background:

• Dielectric materials are crucial for electronics and power systems.
• Polymer dielectrics offer advantages over ceramics but are limited by low working temperatures.
• Extreme conditions in applications like electric vehicles necessitate high-temperature dielectric solutions.

Purpose of the Study:

• To develop polymer dielectrics with enhanced thermal stability and high-voltage energy storage capabilities.
• To investigate the effect of boron nitride nanosheets on the dielectric properties of crosslinked polymer nanocomposites.
• To overcome the temperature limitations of conventional polymer dielectrics for advanced applications.

Main Methods:

• Fabrication of crosslinked polymer nanocomposites incorporating boron nitride nanosheets.
• Characterization of dielectric properties, including breakdown strength and energy density, over a wide temperature range.
• Evaluation of electrical conduction, thermal conductivity, and mechanical flexibility.

Main Results:

• The developed nanocomposites exhibit stable dielectric properties across broad temperature and frequency ranges.
• Achieved record high-voltage capacitive energy storage at 250°C (403 MV/m breakdown strength, 1.8 J/cm³ energy density).
• Demonstrated significantly lower electrical conduction and improved thermal conductivity compared to pristine polymers, mitigating thermal runaway.

Conclusions:

• Boron nitride nanosheet incorporation enhances thermal stability and dielectric performance of polymer nanocomposites.
• These materials are suitable for high-temperature, high-voltage energy storage applications.
• The lightweight, flexible, and photopatternable nature of the nanocomposites broadens their applicability in advanced electronics.