Cellulose nanofiber as mask/personal protective equipment surface agent for enhanced anti-bacterial performance

Abstract

The utilization of face-covering masks as an extended form of personal protective equipment has led to exponential waste measures during the COVID-19 pandemic, with estimations of up to 7200 tons of medical-type waste daily. A primary cause of this waste is surgical layered disposable masks that are constructed by melt-blown nonwovens usually made of non-biodegradable thermoplastic polymers like polypropylene. To increase widespread sustainable options to the public, commercialized or do-it-yourself-based fabric masks serve as a solution, but their resistance to harmful molecules is less than that of the medical-grade masks due to the fabric structure that leaves space for penetration. This project examines a water-soluble dispersion composed of cellulose nanofiber and polyvinyl alcohol, as a spray agent capable of treating the mask fabric surface to promote protection and sustainability against harmful aerosol particles. Cellulose nanofiber spray is also low-cost and biocompatible and could allow multi-use through home laundering. Polyvinyl alcohol was chosen as the water-soluble bonding system and polymer matrix to effectively adhere cellulose nanofiber onto the mask surface. This project follows the biomimic concept of dragonfly wings having uneven nanopillar surfaces to trap and rip bacterial membranes, as the spray decreases the water droplet contact angle on fabric surface, resulting in an increase in adhesion for incident bacteria and/or viruses.