Polyethylene/Polypropylene Bicomponent Spunbond Air Filtration Materials Containing Magnesium Stearate for Efficient Fine Particle Capture

Particulate matter (PM) poses a threat to people's living environment. Fresh air ventilation systems can filter particulate matter and play an important role in enhancing indoor air quality. A high filtration efficiency material with low pressure drop prolongs the service life of the filters and reduces energy consumption. However, maintaining the long-term storage of charge in electret materials remains a challenge. Herein, we report a novel sheath/core bicomponent spunbond (BCS) electret material with low pressure drop and improved charge stability using polyethylene/polypropylene (PE/PP) as the matrix polymer and magnesium stearate (MgSt) as the charge enhancer. Benefiting from the three-dimensional (3D) fluffy structure created by the spunbond technique and through-air reinforcement, the resulting electret materials exhibit a low pressure drop of 37.92 Pa, excellent dust holding capacity of 10.87 g m-2, and high filtration efficiency of 98.94%. Moreover, due to the introduction of MgSt, the filtration efficiency only decreased by 4.1% in 90 days. The successful fabrication of PE/PP BCS materials with MgSt not only provided a promising medium for particle capture but also developed a new approach for the design of fresh air filtration materials.