We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Simulation of the Long-Term Ageing of Polypropylene-Made Disposable Surgical Masks and Filtering Facepiece Respirators
Summary
Researchers artificially aged polypropylene surgical masks under simulated environmental conditions and modeled their long-term oxidative degradation, finding that mask polymers undergo progressive fragmentation that will generate microplastics for years to decades after disposal in the environment.
The main purpose of this work is to contribute to understanding the mechanism of oxidation of the polymeric components of common disposable masks used during the COVID-19 pandemic to offer the chemical basis to predict their long-term behaviour under typical environmental conditions. Artificial ageing of representative mask layers under isothermal conditions (110℃) or accelerated photoageing showed that all the PP-made components underwent a fast oxidation process, following the typical hydrocarbon oxidation mechanism. In particular, yellowing and the melting temperature drop are early indicators of their diffusion-limited oxidation. Morphology changes also induced a loss of mechanical properties, observable as embrittlement of the fabric fibres. Results were validated through preliminary outdoor ageing of masks, which allows us to predict they will suffer fast and extensive oxidation only in the case of contemporary exposure to sunlight and relatively high environmental temperature, leading to their extensive breakdown in the form of microfiber fragments, i.e., microplastics.