South Korean researchers have developed a face mask that decomposes within a month and can be used repetitively. The newly developed mask is expected to help solve the problem of mask waste, which has become a new source of pollution amid the prolonged COVID-19 pandemic.
A team of researchers at the Korea Research Institute of Chemical Technology including head researcher Hwang Seong-yeon and senior researchers Oh Dong-yeop and Park Je-yeong said on Monday that they developed a biodegradable face mask that is moisture-resistant and multi-usable as well as delivering the same protection as the KF94 model.
Most of the materials of a face mask, such as outer cloth and ear loops, cause environmental pollution since they are non-disposable and non-recyclable.
The research team made a mesh-type non-woven fabric that is difficult for viruses to pass through by layering polybutylene succinate (PBS) nano-fiber, a biodegradable plastic that has similar tensile strength to polypropylene mesh. The researchers then coated the fabric with chitosan extracted from crab shell. Chitosan nanoparticles are positively charged, causing viruses or fine dust, which are negatively charged, to adhere. A mix of nanofibers and microfibers has made the mask highly breathable while keeping viruses and fine dust at bay. Unlike conventional mask filters that use an electrostatic method, which is non-resistant to moisture, the newly-developed filter offers similar protection even after being reused for more than 45 times and fully decomposed in the soil within 28 days.
The filter is found to block 98.3% of fine particulate matter (PM 2.5). The research team said the filter offers the same level of protection as KF94 masks. Their work was published as a cover paper of the Advanced Science on March 17.