Electrospun Multiwalled Carbon Nanotubes/Poly(m‐Phenylene Isophthalamide) Nanofibrous Membrane for an Efficient High‐Temperature <scp>PM0.3</scp> Filter

ABSTRACT Multiwalled carbon nanotubes (MWCNTs)/poly(m‐phenylene isophthalamide) (PMIA) nanofibrous membranes were fabricated to systematically investigate the influence of MWCNT content on filtration performance, mechanical properties, and resistance to harsh environments. The incorporation of an appropriate amount of MWCNTs promotes the formation of bonding structures, induces nanoscale surface protrusions, and facilitates the development of sub‐100 nm fibers within the fibrous network, thereby simultaneously improving filtration efficiency and mechanical strength. The membrane containing 0.9 wt% MWCNTs exhibits optimal performance, achieving a tensile strength of 35.153 MPa and a filtration efficiency of 99.720% against PM0.3 (particulate matter with an aerodynamic diameter ≤ 0.3 μm). Notably, the MWCNTs/PMIA composite membranes exhibit superior performance over their pristine PMIA counterparts, especially under high‐temperature conditions and chemically harsh environments. Upon exposure to 300°C, 30 wt% H 2 SO 4 , and 10 wt% NaOH, the tensile strength of the composite membrane increases by 234%, 235%, and 238%, respectively. Furthermore, filtration efficiency improves by approximately 133% after operation at 250°C. These results indicate that the incorporation of MWCNTs synergistically enhances filtration performance, mechanical properties, and environmental stability, offering valuable insights for the design and development of advanced PM0.3 filtration materials.