Electret melt-blown nonwovens are widely used for air purification due to their low pressure drop and high filtration efficiency. However, the charge stability could be affected by the ambient temperature and humidity, reducing the filtration efficiency, resulting in the electret melt blown filter not providing effective protection. Herein, we used corona charge to prepare electret melt-blown nonwovens and systematically studied the effects of different temperature and humidity on the structure, morphology, filtration performance, and surface potential within 24 h. The effect of treatment temperature and humidity on pressure drop was minimal because the fiber morphology and web structure of melt-blown nonwovens were not damaged. When the treatment temperature was lower than 70 °C, the effect on the filtration efficiency of the sample was small, but when the temperature increased to 90 or 110 °C, the filtration efficiency decreased significantly with the increase of the treatment time, and the surface potential also declined similarly. In conclusion, high temperatures will lead to charge escape and reduce the electrostatic adsorption effect. Furthermore, at the same temperature, increasing relative humidity can accelerate the charge release and make the filtration efficiency drop more. After the sample was treated at 110 °C and 90% relative humidity for 24 h, the filtration efficiency decreased from 95.49% to 38.16% at a flow rate of 14.16 cm s−1, and the surface potential dropped to the lowest value of −1.01 kV. This result shows that all links of electret melt-blown filter material from raw material to final use should be avoided in high temperature and high humidity conditions to ensure the protection effect.

A multifunctional composite filter combined with nanocrystalline MnO2 and a PE/PP bicomponent fiber by introducing corona charge technology has been fabricated and exhibited excellent filtration, adsorption and catalytic abilities in air pollutant abatement.

Fibrous composite materials provide distinct advantages in large surface area and enhanced molecular transport through the media, lending themselves to diverse applications. Despite substantial development in synthetic methods, it is still lacking in insights into structure-property relationships that can correlate features of the functional materials to absorptive, transport, and catalytic performance of the composites. Herein, for the first time, a systematic structure-property-function analysis is provided for Zr-based metalorganic frameworks (MOFs) coated onto polypropylene nonwoven textiles. MOF fraction on the fabric and defect density in MOF microstructures are controlled by an in situ seeded growth, where fiber surfaces are pretreated with metal-oxide by atomic layer deposition. The best performing MOF-fiber composite shows a rapid catalytic hydrolysis rate for a chemical warfare agent simulant, p-nitrophenyl phosphate with t 1/2 < 5 min, and a significant permeation restriction of a real agent GD-vapor through the composite. Of added advantage is the observed moisture vapor transport rate of 15 000 g m −2 day −1 for the composite, which is notably superior to that of other commercially available chemical-protective fabrics. The chemical-protective composites realized in this work overcome the breathability/detoxification trade-off and show promise for the materials to be deployed in a realistic field.

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