{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,29]],"date-time":"2025-12-29T08:04:36Z","timestamp":1766995476189,"version":"3.48.0"},"reference-count":36,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2025,12,27]],"date-time":"2025-12-27T00:00:00Z","timestamp":1766793600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Federal Ministry of Research, Technology and Space, the Lower Saxony Ministry of Science and Culture and the Joint Science Conference in the federal-state program \u201cFH-Personal\u201d"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>This study evaluates the influence of repeated processing, \u03b3-irradiation (25 kGy), and additive formulation including Irgafos 168 (I168), Tinuvin 622 (T622), and Calcium Stearate (CaSt) on a polypropylene copolymer (PP-C). Motivated by medical technology applications, the study assessed effects on optical properties, yellowing, crystallization, mechanical performance, and viscosity using a full factorial design of experiments (DoE). Results showed \u03b3-irradiation had the most significant impact, especially on zero-shear viscosity, which decreased by 84% after the first irradiation. The Yellowness Index (YI) changed measurably, but discoloration remained imperceptible. Crystallization temperature was influenced mainly by additive interactions, while specific enthalpy was affected by processing and \u03b3-irradiation. Elongation at break and tensile strength were predominantly influenced by \u03b3-irradiation, with elongation at break being a sensitive indicator of degradation. Zero-shear viscosity, correlating with molecular weight, was mainly controlled by \u03b3-irradiation, indicating chain scission without critical embrittlement. Overall, \u03b3-irradiation exerted a stronger effect than processing or additive formulation. Zero-shear viscosity proved a reliable measure of degradation, while elongation at break offered complementary insights. Despite significant viscosity reduction, mechanical properties remained high, confirming the material\u2019s suitability for its intended applications.<\/jats:p>","DOI":"10.3390\/polym18010083","type":"journal-article","created":{"date-parts":[[2025,12,29]],"date-time":"2025-12-29T07:52:59Z","timestamp":1766994779000},"page":"83","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Design of Experiment (DoE) Approach to Evaluate the Recyclability of a Polypropylene Copolymer in Medical Technology Under the Aspect of Additive Composition"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-7985-6790","authenticated-orcid":false,"given":"Nele","family":"Espelage","sequence":"first","affiliation":[{"name":"Laboratory of Polymer Engineering, University of Applied Sciences Osnabr\u00fcck, Albrechtstra\u00dfe 30, 49076 Osnabr\u00fcck, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9541-1889","authenticated-orcid":false,"given":"Markus Lothar","family":"Susoff","sequence":"additional","affiliation":[{"name":"Laboratory of Polymer Engineering, University of Applied Sciences Osnabr\u00fcck, Albrechtstra\u00dfe 30, 49076 Osnabr\u00fcck, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cathrin","family":"Schr\u00f6der","sequence":"additional","affiliation":[{"name":"Laboratory of Polymer Engineering, University of Applied Sciences Osnabr\u00fcck, Albrechtstra\u00dfe 30, 49076 Osnabr\u00fcck, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Peter","family":"Bl\u00f6mer","sequence":"additional","affiliation":[{"name":"Center for Materials and Technology, Private University of Applied Sciences for Business and Technology, Am Campus 3, 49356 Diepholz, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5174-6879","authenticated-orcid":false,"given":"Svea","family":"Petersen","sequence":"additional","affiliation":[{"name":"Laboratory of Polymer Engineering, University of Applied Sciences Osnabr\u00fcck, Albrechtstra\u00dfe 30, 49076 Osnabr\u00fcck, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,27]]},"reference":[{"key":"ref_1","first-page":"199","article-title":"Recycling of medical plastics","volume":"4","author":"Joseph","year":"2021","journal-title":"Adv. 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