{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,11]],"date-time":"2025-11-11T14:00:17Z","timestamp":1762869617466,"version":"build-2065373602"},"reference-count":59,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T00:00:00Z","timestamp":1760140800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002322","name":"Coordination of Higher Education Personnel\u2014CAPES","doi-asserted-by":"publisher","award":["001"],"award-info":[{"award-number":["001"]}],"id":[{"id":"10.13039\/501100002322","id-type":"DOI","asserted-by":"publisher"}]},{"name":"CAPES Institutional Internationalization Program\u2014CAPES-PrInt","award":["88887.889025\/2023-00"],"award-info":[{"award-number":["88887.889025\/2023-00"]}]},{"DOI":"10.13039\/501100001807","name":"S\u00e3o Paulo Research Foundation\u2014FAPESP","doi-asserted-by":"publisher","award":["2016\/25703-2"],"award-info":[{"award-number":["2016\/25703-2"]}],"id":[{"id":"10.13039\/501100001807","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003593","name":"CNPq research grant","doi-asserted-by":"publisher","award":["308760\/2022-0"],"award-info":[{"award-number":["308760\/2022-0"]}],"id":[{"id":"10.13039\/501100003593","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>UV-C radiation has emerged as a germicidal agent against pathogens, particularly following the COVID-19 pandemic. While UV-C effectively reduces cross-contamination in hospitals, it induces photodegradation in polymer devices, potentially damaging and posing risks to patient safety. Therefore, it is crucial to detect the effects of UV-C photodegradation on early stages, as well as the effects of prolonged UV-C exposure. In this study, we investigated the UV-C photodegradation (254 nm, 471 kJ\/mol) of isotactic polypropylene homopolymer (PP), commonly used in medication packaging. The impact of UV-C on PP was evaluated through rheology and infrared spectroscopy. Surface energy was measured by the contact angles formed by drops of water and diiodomethane. The effects of photodegradation on the polymer\u2019s morphology were examined using scanning electron microscopy, and the melting temperature and crystallinity by differential scanning calorimetry. Lastly, the effect of UV-C on molecular mobility was studied using 1H Time Domain Nuclear Magnetic Resonance (1H TD-NMR). These techniques proved to be valuable tools for identifying the early stages of UV-C photodegradation, and 1H TD-NMR was a sensitive method to identify the chain branching as a photodegradation product. This study highlights the impact of UV-C on PP photodegradation and hence the importance of understanding UV-C-induced degradation.<\/jats:p>","DOI":"10.3390\/polym17202727","type":"journal-article","created":{"date-parts":[[2025,10,14]],"date-time":"2025-10-14T05:48:21Z","timestamp":1760420901000},"page":"2727","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["1H Time Domain Nuclear Magnetic Resonance and Oscillatory Rheology as a Tool for Uncovering the Impact of UV-C Radiation on Polypropylene"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0478-6480","authenticated-orcid":false,"given":"Jessica Caroline Ferreira","family":"Gimenez","sequence":"first","affiliation":[{"name":"Department of Chemistry, Exact Sciences and Technology Center (CCET), Federal University of S\u00e3o Carlos (UFSCar), Rodovia Washington Lu\u00eds, Km 235, SP-310, S\u00e3o Carlos 13565-905, SP, Brazil"},{"name":"Department of Mechanical Engineering, \u00c9cole de Technologie Sup\u00e9rieure (\u00c9TS), 1100 Notre-Dame St W, Montr\u00e9al, QC H3C 1K3, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3139-8667","authenticated-orcid":false,"given":"Sophia Helena Felisbino","family":"Bonatti","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Exact Sciences and Technology Center (CCET), Federal University of S\u00e3o Carlos (UFSCar), Rodovia Washington Lu\u00eds, Km 235, SP-310, S\u00e3o Carlos 13565-905, SP, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5947-3879","authenticated-orcid":false,"given":"Marcos Vin\u00edcius","family":"Basaglia","sequence":"additional","affiliation":[{"name":"Department of Materials Engineering, Exact Sciences and Technology Center (CCET), Federal University of S\u00e3o Carlos (UFSCar), Rodovia Washington Lu\u00eds, Km 235, SP-310, S\u00e3o Carlos 13565-905, SP, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rodrigo Henrique dos Santos","family":"Garcia","sequence":"additional","affiliation":[{"name":"Physics Institute of S\u00e3o Carlos, IFSC, University of S\u00e3o Paulo, Avenida Trabalhador S\u00e3ocarlense, 400, S\u00e3o Carlos 13566-590, SP, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5814-3624","authenticated-orcid":false,"given":"Alef","family":"dos Santos","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Exact Sciences and Technology Center (CCET), Federal University of S\u00e3o Carlos (UFSCar), Rodovia Washington Lu\u00eds, Km 235, SP-310, S\u00e3o Carlos 13565-905, SP, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lucas Henrique","family":"Staffa","sequence":"additional","affiliation":[{"name":"Department of Materials Engineering, Exact Sciences and Technology Center (CCET), Federal University of S\u00e3o Carlos (UFSCar), Rodovia Washington Lu\u00eds, Km 235, SP-310, S\u00e3o Carlos 13565-905, SP, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mazen","family":"Samara","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, \u00c9cole de Technologie Sup\u00e9rieure (\u00c9TS), 1100 Notre-Dame St W, Montr\u00e9al, QC H3C 1K3, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6549-2980","authenticated-orcid":false,"given":"Silvia Helena Prado","family":"Bettini","sequence":"additional","affiliation":[{"name":"Department of Materials Engineering, Exact Sciences and Technology Center (CCET), Federal University of S\u00e3o Carlos (UFSCar), Rodovia Washington Lu\u00eds, Km 235, SP-310, S\u00e3o Carlos 13565-905, SP, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2461-4755","authenticated-orcid":false,"given":"Eduardo Ribeiro","family":"de Azevedo","sequence":"additional","affiliation":[{"name":"Physics Institute of S\u00e3o Carlos, IFSC, University of S\u00e3o Paulo, Avenida Trabalhador S\u00e3ocarlense, 400, S\u00e3o Carlos 13566-590, SP, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Emna","family":"Helal","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, \u00c9cole de Technologie Sup\u00e9rieure (\u00c9TS), 1100 Notre-Dame St W, Montr\u00e9al, QC H3C 1K3, Canada"},{"name":"NanoXplore Inc., 4500 Thimens Blvd, Saint-Laurent, Montr\u00e9al, QC H4R 2P2, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8935-5443","authenticated-orcid":false,"given":"Nicole Raymonde","family":"Demarquette","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, \u00c9cole de Technologie Sup\u00e9rieure (\u00c9TS), 1100 Notre-Dame St W, Montr\u00e9al, QC H3C 1K3, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6640-664X","authenticated-orcid":false,"given":"Manoel Gustavo Petrucelli","family":"Homem","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Exact Sciences and Technology Center (CCET), Federal University of S\u00e3o Carlos (UFSCar), Rodovia Washington Lu\u00eds, Km 235, SP-310, S\u00e3o Carlos 13565-905, SP, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sandra Andrea","family":"Cruz","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Exact Sciences and Technology Center (CCET), Federal University of S\u00e3o Carlos (UFSCar), Rodovia Washington Lu\u00eds, Km 235, SP-310, S\u00e3o Carlos 13565-905, SP, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"356","DOI":"10.1016\/j.ijfoodmicro.2013.07.021","article-title":"Fate of E. coli O157:H7, Salmonella Spp. and Potential Surrogate Bacteria on Apricot Fruit, Following Exposure to UV-C Light","volume":"166","author":"Yun","year":"2013","journal-title":"Int. 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