Preparation of long-lasting electret fiber felt by centrifugal air-assisted spinning process and electret post-treatment

The electret ultra-fine fiber filter material is prepared by the centrifugal airflow-assisted process. Moreover, the material can be used in the field of air filtration. A longitudinal air pressure draft sprinkler and a refined centrifugal spinning jet were designed to improve the fiber quality. According to different process parameters, in order to optimize the process of preparing ultra-fine fiber by centrifugal spinning, including the mass fraction of SiO2 (0%, 0.5%, 1%, and 1.5%), the effect of draft pressure (0, 0.05, and 0.15 MPa) on the diameter and morphology of the fiber was investigated. In addition, the effect of air pressure on the diameter and morphology of the fiber was investigated. The effects of key process parameters within the range of common production parameters on fiber quality and fiber morphology were expounded. For the prepared fiber felt, a preliminary test of the physical properties related to the molecular structure and filtration performance of the material was carried out, including the FTIR test and surface contact angle test of the material. After that, we carried out electret treatment of the ultra-fine fiber felt prepared by the centrifugal airflow-assisted process. Besides, we compared the surface electric potential and stability of the fiber felt by the needle electret process and wire electret process, respectively. Finally, the key physical properties of the filter media were tested. In addition, the filtration efficiency and resistance indices of the fiber felt prepared with different parameters were compared. Moreover, the effects of fiber morphology and the electret process on the performance of the filter felt were obtained. The study can provide new ideas and references for the preparation of electret ultra-fine fiber filter media.