{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T05:03:37Z","timestamp":1787029417433,"version":"build-2736575974"},"reference-count":44,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2023,2,17]],"date-time":"2023-02-17T00:00:00Z","timestamp":1676592000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Xunta de Galicia","award":["ED431G2019\/03"],"award-info":[{"award-number":["ED431G2019\/03"]}]},{"name":"Xunta de Galicia","award":["ED431B 2021\/23"],"award-info":[{"award-number":["ED431B 2021\/23"]}]},{"name":"European Regional Development Fund","award":["ED431G2019\/03"],"award-info":[{"award-number":["ED431G2019\/03"]}]},{"name":"European Regional Development Fund","award":["ED431B 2021\/23"],"award-info":[{"award-number":["ED431B 2021\/23"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>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 understand their long-term behavior under typical environmental conditions. Artificial aging of representative mask layers under isothermal conditions (110 \u00b0C) or accelerated photoaging 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 fibers. Results were validated through preliminary outdoor aging 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.<\/jats:p>","DOI":"10.3390\/polym15041001","type":"journal-article","created":{"date-parts":[[2023,2,17]],"date-time":"2023-02-17T03:27:41Z","timestamp":1676604461000},"page":"1001","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Study of the Long-Term Aging of Polypropylene-Made Disposable Surgical Masks and Filtering Facepiece Respirators"],"prefix":"10.3390","volume":"15","author":[{"given":"Sandra","family":"Carreiras-Su\u00e1rez","sequence":"first","affiliation":[{"name":"Departamento de Qu\u00edmica F\u00edsica, Facultade de Qu\u00edmica, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain"},{"name":"Centro Singular de Investigaci\u00f3n en Qu\u00edmica Biol\u00f3xica e Materiais Moleculares (CiQUS), Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8877-5246","authenticated-orcid":false,"given":"Lidia","family":"Dom\u00ednguez-Ramos","sequence":"additional","affiliation":[{"name":"Departamento de Qu\u00edmica F\u00edsica, Facultade de Qu\u00edmica, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain"},{"name":"Centro Singular de Investigaci\u00f3n en Qu\u00edmica Biol\u00f3xica e Materiais Moleculares (CiQUS), Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain"},{"name":"Departamento de Ingenier\u00eda Qu\u00edmica, ETSE, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1300-6711","authenticated-orcid":false,"given":"Massimo","family":"Lazzari","sequence":"additional","affiliation":[{"name":"Departamento de Qu\u00edmica F\u00edsica, Facultade de Qu\u00edmica, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain"},{"name":"Centro Singular de Investigaci\u00f3n en Qu\u00edmica Biol\u00f3xica e Materiais Moleculares (CiQUS), Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"531","DOI":"10.1021\/acsapm.0c01151","article-title":"Polymer Materials for Respiratory Protection: Processing, End Use, and Testing Methods","volume":"3","author":"Armentano","year":"2021","journal-title":"ACS Appl. 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