A new type of non-woven filter composed of polysulfone and polyurethane nanofibers is proposed. Compared with nanofiber nonwovens with common structure, honeycomb nonwovens have higher filtration efficiency (about 99.939%), better mechanical strength (about 105.24 N g(-1)) and improved quality factor (About 0.04 Pa-1).
To control the fiber density and the arrangement across the electrospun mat, the electrospun nanofiber membrane was designed to remove aerosol particles. The air filtration efficiency of the membrane is in the range of 77.7% to 99.616%, and the quality factor is between 0.0026 and 0.0204. This shows that changing the fiber density is an effective way to improve air filtration performance.
In this study, we prepared polydimethylsiloxane (PDMS) modified polyurethane-polycaprolactone nanofiber membranes by electrospinning technology. The film exhibits robust mechanical properties, high strength (breaking stress = 11.7MPa) and excellent thermal stability. This indicates that they will be promising candidates for waterproof and breathable applications.
An efficient, environmentally friendly, translucent and multifunctional air purification filter is reported. For PM with sizes smaller than 2.5 and 10μm, the air filtration efficiency of the manufactured SNAF can reach 90% and 97%, respectively, which exceeds the performance of commercial semi-HEPA filters. After use, SNAF may degrade naturally.
A protein functionalized material with a hierarchical structure. This composite material is made of bacterial nanocellulose wrapped in protein nanoparticles and microcellulose fibers in wood pulp. The filtration efficiency for PM1-2.5 is as high as 99.5%, but the normalized pressure drop is only 0.194 kPa/g.
The new polyvinylidene fluoride (PVDF) nanofiber multilayer membrane has a very high filtration efficiency: the filtration efficiency of both PM2.5 and PM0.1 exceeds 99.00%. The permeability of the membrane changed from 288 to 3275 L/m (2) hbar.
UiO-66 was introduced into polyvinylidene fluoride/Ti(OH)(4) composite fabric by electrospinning, and its use in chemical protective clothing was evaluated. All samples have high moisture transmission and filtration efficiency. The addition of TEA reduces the air permeability of the fabric, but increases the catalytic activity of the composite fabric to DMNP and DFP.
The pressure drop is proportional to the surface velocity and the thickness of the filter. The product of drag coefficient and Reynolds number is a function of bulk density and Knudsen number. The semi-empirical model can reasonably predict the pressure drop on the nylon electrospun nanofiber filter, with a median relative error of 4.3%.
Summarized the latest developments in electrospun bionic nanofiber materials, which are inspired by nature, including lotus leaves, water ider legs, polar bear hair, spider webs and honeycombs. The potential applications of the prepared electrospinning bionic materials in self-cleaning, oil/water separation, air filtration, and heat insulation are analyzed.
The self-bending zein fabric has many important functions for filtration. Compared with traditional fabrics with rod-shaped fibers, the filtration performance is improved at the same time, including improved collection efficiency, filtration capacity and stability of air pressure drop, and reduced airflow resistance.
Developed a filter medium composed of electret polyethersulfone/barium titanate nanofiber membrane (PES / BaTiO3 NFM) integrated on a non-woven polypropylene substrate. The electret PES/BaTiO3 NFM1.5 medium with a low basis weight of 4.32 gm(-2) still shows a high filtration efficiency of 99.99% and a low pressure drop of 67 Pa after being treated at 200°C for 45 minutes.