Fabrication of gelatin nanofiber webs via centrifugal spinning for N95 respiratory filters

Abstract

Due to the impact of the Covid-19 pandemic, the usage of numerous protective face masks has faced an explosion in demand around the world. Therefore, the need to reduce the environmental pollution caused by disposable single-use face masks has become vital. Recently, alternative raw material solutions have been discussed to eliminate the consumption of single-use plastics. Within this research, gelatin nanofibers were fabricated via centrifugal spinning technique, and filtration media were investigated in terms of air permeability and filtration efficiency. In addition, morphological properties were examined with scanning electron microscopy. Fabricated fibers have a changing average diameter range from 232 to 778 nm, and targeted 95% filtration efficiency was achieved in several compositions. It was proven that biodegradable gelatin nanofibers could be a sustainable alternative for disposable N95 respiratory filters.

Comparative Investigation of Electrospun and Centrifugal Spun Polylactic Acid for Filtration Performance and Reusability

“…This difference in Q f is primarily attributable to the inherent fiber spinning mechanisms of the two processes. CS samples exhibit a wider distribution of micro ( d > 1.0 μm) and nanofibers ( d < 1.0 μm), resulting in less tightly packed structures that offer less resistance to breathing . Such “bimodal” combination of fiber diameters also yielded similarly low Δ p with high FE via a modified electrospinning of PLA nanofibers by Wang et al; this was attributed to the high porosity of 91% in tandem with small pore size 0.73 μm, with each parameter leading to the high Δ p and FE, respectively.…”

“…To further analyze this finding, Figure compares an aggregate filtration performance parameter called quality factor, Q f , of CS and ES PLA against aerial mass for given mean fiber diameters. Q f is calculated using eq , Q normalf = prefix− ln ( 1 − η ) / normalΔ p where Δ p is the pressure drop and η is the FE. , …”

“…CS samples exhibit a wider distribution of micro (d > 1.0 μm) and nanofibers (d < 1.0 μm), resulting in less tightly packed structures that offer less resistance to breathing. 36 Such "bimodal" combination of fiber diameters also yielded similarly low Δp with high FE via a modified electrospinning of PLA nanofibers by Wang et al; 29 this was attributed to the high porosity of 91% in tandem with small pore size 0.73 μm, with each parameter leading to the high Δp and FE, respectively. It is reasonable to conjecture that a similar combination of high porosity and small pore size is present based on the wider diameter distribution of CS samples, effectively approaching "bimodal" distribution as seen by Wang et al 29 Other morphological factors such as thickness may be considered; however, no significant differences in thicknesses between CS and ES samples were observed as both were compactly deposited as ∼0.04 mm layer on top of a much thicker (0.24 mm) PP spunbound substrate (see Supporting Figure S5 for the photographs of CS and ES samples, and their associated data tabulated in Table S1).…”

“…There has been a growing interest in the utility of renewable polymers as nanofibers, driven by increasing concerns over the environmental impact of single-use plastics. Polylactic acid (PLA) is a biodegradable polymer which has gained attention for its desirable properties in PPE applications. − PLA exhibits excellent mechanical properties, processability, hydrophobicity, and antimicrobial activity, making it an ideal choice for biomedical applications. − PLA-based filters offer a unique advantage over other commercial filters as they can be fully decomposed . Additionally, PLA is derived from plant-based starch, such as corn, wheat, and cassava, making it an environmentally friendly raw material. − Notably, Soo et al investigated decomposition of three-layer PLA respirator; timely decomposition is difficult and requires specific chemical treatment although smaller diameter layer, e.g., melt-blown PLA, degrades more quickly than spunbond PLA due to higher specific surface area .…”

Degradation and Mechanical Behavior of Fish Gelatin/Polycaprolactone AC Electrospun Nanofibrous Meshes

“…Pristine gelatin and PCL micro and nanofibers have been produced by several spinning methods including electrospinning, [28][29][30][31][32] gas-jet spinning, [33,34] centrifugal spinning, [35,36] and gyration spinning. [37] While similar fiber diameters, fibrous material properties, and process productivities can be achieved depending on the method realization, precursor concentration, and spinneret design, electrospinning has been, so far, the most commonly used in the production of PCL, gelatin, and specially blended gelatin/PCL nanofibers.…”