Electrostatic Capture Efficiency Enhancement of Polypropylene Electret Filters with Barium Titanate

This study reports on the effects of BaTiO3—a high dielectric constant additive—addition on charging and filtration properties of meltblown polypropylene (PP) electret filters. Since electrostatic capture efficiency of electret filters is mainly dependent on electrical forces, surface potential and aerosol filtration properties were analyzed and compared. Due to quasi-permanent nature of electret property, stability of charging and filtration performance was also investigated via following an isothermal charge decay procedure. Addition of BaTiO3 did not alter fiber morphology significantly. Particularly, the stability of electrostatic filtration performance was found to be promising with the addition of BaTiO3. Possible microstructural changes after addition of BaTiO3 were investigated via wide angle X-ray diffraction. Changes in crystal structure of PP upon addition of BaTiO3 did not deteriorate electrostatic properties.