Development of disposable filtering mask recycled materials: Impact of blending with recycled mixed polyolefin and their aging stability

A survey on Covid-19 protecting masks habits carried out on the Italian population at the end of 2020 revealed that disposable face masks are the most used, thus resulting in a considerable quantity of waste. Therefore, a separate collection of these devices based on local platforms such as schools, offices and factories is proposed. This would limit collecting costs, ensure the origin and quantity and simplify the sanitizing treatment of the masks, in order to allow their introduction into the industrial recycling stream of plastic materials. In this scenario, an urban separate waste collection material (namely mixed polyolefin) was selected and melt blended in several ratios with the disposable filtering masks. Two recycling solutions have been envisaged: the use of the filtering part alone or the joint introduction of the ear loops. Compared to the mixed polyolefin, the resulting recycled materials from filtering face masks have lower viscosity but comparable toughness and superior stiffness and strength. The presence of ear loops in the recycled improves the rigidity but slightly decrease the viscosity and worsen both the strength and toughness. Furthermore, conceiving an outdoor application, the stability to photo oxidation was investigated through an accelerated aging process. The elaborated degradation rate of the masks material is similar to a commercial polypropylene, while for the mixed polyolefin is greatly reduced. The mixed compounds have intermediate degradation rates.