Enhanced thermal stability of electrical properties in PVDF/PMMA blend

Electrostatic energy storage devices with high energy density play an important role in the rapid development of modern electronic technology, especially in pulse power supply devices, hybrid vehicle power systems. The thermal stability of the polymer structure is crucial to achieve stable energy density of ferroelectric polymer capacitors at high temperature. In this work, poly (vinylidene fluoride)/polymethyl methacrylate (PVDF/PMMA) blends of different additions are used to obtain better thermal stability and temperature stability of electrical properties. PVDF/PMMA composites with different components (90/10, 86.5/13.5, 83/17, 80/20 in mass ratio) were researched. It was found that PVDF/PMMA (80/20) had a higher breakdown strength (Eb=288.5kV/mm) and lower conductivity at 70°C. The energy density of the blend is about 4.82J/cm3, which is about 3 times that of polypropylene. Our research provides an idea for the development of dielectric materials with high energy storage density and thermal stability.