Ultrafine PVDF Nanofibers for Filtration of Air-Borne Particulate Matters: A Comprehensive Review

Abstract

The ongoing global pandemic has bestowed high priority uponthe separation of air-borne particulate matters (PMs), aerosols, etc. using nonwoven fibrous materials, especially for face masks as a means of personal protection. Although spunbond or meltblown nonwoven materials are amongst the forerunners for polymer microfiber-based face mask or air filter development in mass scale, relatively new process of nonwoven manufacturing such as electrospinning is gaining a lot of momentum amongst the filter membrane manufacturers for its scalability of nanofiber-based filter membrane fabrication. There are several nanofiber-based face masks developing industries, which claim a very high efficiency in filtration of particulate matters (PM0.1–10) as well as other aerosols for their products. Polyvinylidene fluoride (PVDF), which is commonly known for its use of tactile sensors and energy harvesters, due to its piezoelectric property, is slowly gaining popularity among researchers and developers as an air filter material. Electrospun PVDF nanofibers can be as fine as 50 nm in mass scale, which allows the membrane to have large surface area compared to its volume, enhancing nanofiber–PM interaction. At the same time, the breathability index can be improved through these PVDF nanofiber membranes due to their architectural uniqueness that promotes slip flow around the fibers. The conductive nature of PVDF makes it advantageous as a promising electret filter allowing better capturing of ultrafine particles. This review aims to provide a comprehensive overview of such PVDF nanofiber-based filter membranes and their roles in air filtration, especially its application in filtrate of air-borne PMs.

State-of-the-art review of advanced electrospun nanofiber yarn-based textiles for biomedical applications

“…Electrospun NY-based textiles can serve as the filter layer to construct self-powered face masks that can potentially solve some fatal issues of single-use face masks [ 229 , 230 ]. Some polymers with tribo/piezoelectric characteristics, such as PVDF, PVDF-TrFE, and PVDF-HFP, can be fabricated into electrospinning-based NYs and further constructed into textile-shaped filter layers for face mask application [ 231 , 232 ]. The tribo/piezoelectric nanotextile filter layer can generate electrical charges during the breathing process, which can produce strong electrostatic attraction to effectively block the virus-containing aerosols [ 233 , 234 ].…”

Poly(vinylidene fluoride) electrospun nonwovens morphology: Prediction and optimization of the size and number of beads on fibers through response surface methodology and machine learning regressions

“…Ridge regression addresses some of the problems of ordinary least squares by imposing a penalty on the size of the coefficients, preventing overfitting. 64 The implemented algorithm minimized the loss function E RR shown in equation (2), where y i is the response variable for the i th sample and b y i the predicted value. The weight w j is squared, multiplied by an L2 penalty term (λ) and added to the residual sum of squares.…”

“…1 One of its outstanding applications is the development of poly(vinylidene fluoride) (PVDF) electrospun filters for high-efficiency face masks regarding the covid-19 outbreak. 2…”

Reuse of Textile Waste to Production of the Fibrous Antibacterial Membrane with Filtration Potential

“…Several groups studied electrospun nanofibers with various morphologies by using polymer materials, such as polyacrylonitrile [ 32 ], polystyrene [ 33 ], poly (ε-caprolactone) [ 34 ], cellulose acetate (CA) [ 35 ], silk fibroin (SF) [ 36 ], poly(lactic acid) (PLA) [ 37 ], poly(vinyl alcohol) (PVA) [ 38 , 39 ], polyvinylidene fluoride (PVDF) [ 40 ], poly(ethylene terephthalate) (PET) [ 21 ] and poly(methyl methacrylate) [ 41 ], for use in air filtration applications.…”