Development of biodegradable composites based on Poly(Lactic acid)/Poly(Vinylidene fluoride) blend for use as Nanofibrous filter pads in face mask

Abstract

The increasing use of disposable face masks has raised significant environmental concerns due to their non-biodegradable polymer composition. In response, this study focuses on developing a sustainable alternative by creating biodegradable face mask filters using blends of poly(L-lactic acid) (PLA) and poly(vinylidene fluoride) (PVDF) fabricated through electrospinning. For the electrospinning process, the most suitable solution concentrations for PLA and PVDF were determined to be 10% and 3% w/v, respectively, in an N,N-dimethylacetamide/acetone mixture with a ratio of 4:1 (v/v). Coated and composite filters containing 1% silver nitrate (AgNO3) nanoparticles to enhance their antibacterial properties were also evaluated. The PLA/PVDF/AgNO; electrospun nanofibers were characterized using Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA), confirming the successful incorporation of AgNO3 nanoparticles. The optimized 10/3% w/v PLA/PVDF blend with a 1% AgNO3 coating resulted in an average fiber diameter of 0.45-0.06 um. These electrospun nanofibers exhibited a tensile strength of 6.62-0.25 MPa, a water contact angle of 119.8t1.8 , and significantly improved antibacterial resistance against both Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). Our respective filter pads for face masks not only demonstrated high filtering efficiency against fine particulate matters (PMs) (53% for 0.3 um). The stability of the membrane against severe simulated weathering (ASTM G154:2006) was confirmed, making them suitable for potential use as filters in airconditioning or outdoor spaces. In conclusion, this study has successfully demonstrated the feasibility of developing electrospun nanofibers with enhanced antibacterial properties, highlighting their potential for filtering applications while addressing both environmental and public health concerns.