Multidimensional analysis of morphology–surface potential–filtration performance–hydrolytic degradation behavior relationship of PVDF/PBS nanofibrous filters produced by electro-blowing method

Nanofibrous air filters composed of polyvinylidene fluoride (PVDF) and polybutylene succinate (PBS) were fabricated using the electroblowing method. The influence of blend ratio on fiber morphology, surface potential, electret stability, filtration efficiency (η), and hydrolytic degradation behavior was systematically investigated. While droplet-free and uniform fiber formation was achieved in all compositions, it was observed that as the PBS ratio increased, the solution viscosity increased, leading to a significant rise in fiber diameters from 122 to 212 nm. Surface potential measurements after fabrication and corona treatment revealed that PVDF, due to its high dipole moment, possesses a permanent negative potential retention capacity approximately 3.3 times higher than that of PBS. In filtration tests, the 100% PVDF sample exhibited the highest η (over 99%) and quality factor (QF) both before and after corona treatment. However, as the PBS content increased, η, surface potential, and electret lifetime decreased significantly. Seven-day aging tests showed that electret stability deteriorated rapidly in compositions with PVDF content below 50%. In contrast, samples containing 75% PVDF or more exhibited only limited potential loss (30–35%). Multi-criteria performance analyses (correlation map, z-score mapping, and radar profiles) demonstrated the optimum performance was obtained in the 75% PVDF – 25% PBS composition through the integrated evaluation of metrics such as fiber diameter, surface potential, pressure drop (ΔP), and hydrolytic degradation behavior. Unlike conventional PVDF electret filtration studies primarily focusing on filtration efficiency enhancement, this study systematically investigates the coupled relationship between electrostatic behavior, porous morphology, airflow resistance, filtration performance, and hydrolytic degradation characteristics within electro-blown PVDF/PBS blend nanofibrous systems. These results demonstrate that both high-performance filters and with controlled chemical degradability potential can be produced by combining the superior electrostatic properties of PVDF with the hydrolytic degradation behavior advantage of PBS in controlled proportions.