{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T05:03:35Z","timestamp":1787029415403,"version":"build-2736575974"},"reference-count":54,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,4,18]],"date-time":"2026-04-18T00:00:00Z","timestamp":1776470400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"OMV Downstream GmbH"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Co-pyrolysis of polyolefins (LDPE, PP, PS) mixed with silicone rubber (SR) was investigated using a laboratory-scale pyrolysis apparatus to evaluate product composition, synergistic interactions, and siloxane recovery potential. Synergistic effects were assessed by comparing experimental mass balances and product distributions with calculated values derived from individual polymer pyrolysis. Co-pyrolysis resulted in a reduction in liquid yield and an increase in gaseous products and solid residue compared to calculated values, with liquid yields decreasing by up to \u224815 wt% at high SR content. This shift was accompanied by an enrichment in lighter hydrocarbons in both phases, reaching up to a \u224818% relative increase at high SR content, and by a redistribution towards smaller cyclic siloxanes. Chromatographic analysis confirmed that no new compounds were formed, but the proportion of low molecular weight species increased with silicone content. These effects are attributed to the distinct thermal behavior of the polymers, as silicone rubber does not melt but becomes brittle, allowing molten polyolefins to infiltrate surface cracks and prolong residence time, thereby promoting secondary cracking. Furthermore, recovery of hexamethylcyclotrisiloxane (D3), the primary silicone pyrolysis product, was demonstrated from the liquid co-pyrolysis products via solvent-assisted filtration using ethanol, achieving purities above 99.5% and recovery rates up to \u224875% compared to other possible methods. These findings provide insights into co-pyrolysis behavior and offer a basis for developing strategies for the recovery of siloxane and advanced recycling of mixed polymer waste.<\/jats:p>","DOI":"10.3390\/polym18080989","type":"journal-article","created":{"date-parts":[[2026,4,20]],"date-time":"2026-04-20T13:22:47Z","timestamp":1776691367000},"page":"989","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Co-Pyrolysis of Polyolefins and Silicone Rubber: Effects on Mass Balancing, Product Distribution, and Potential Siloxane Recovery"],"prefix":"10.3390","volume":"18","author":[{"given":"Lukas","family":"Eigenschink","sequence":"first","affiliation":[{"name":"Institute for Chemical Technology of Organic Materials, Johannes Kepler University Linz, Altenberger Stra\u00dfe 69, 4040 Linz, Austria"},{"name":"Institute of Chemical, Environmental and Bioscience Engineering, Vienna University of Technology (TU Wien), Getreidemarkt 9\/166, 1060 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wolfgang","family":"Eder","sequence":"additional","affiliation":[{"name":"OMV Downstream GmbH, Mannsw\u00f6rther Stra\u00dfe 28, 2320 Schwechat, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matthias","family":"Mastalir","sequence":"additional","affiliation":[{"name":"OMV Downstream GmbH, Mannsw\u00f6rther Stra\u00dfe 28, 2320 Schwechat, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6490-5840","authenticated-orcid":false,"given":"Michael","family":"Harasek","sequence":"additional","affiliation":[{"name":"Institute of Chemical, Environmental and Bioscience Engineering, Vienna University of Technology (TU Wien), Getreidemarkt 9\/166, 1060 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1177-1527","authenticated-orcid":false,"given":"Christian","family":"Paulik","sequence":"additional","affiliation":[{"name":"Institute for Chemical Technology of Organic Materials, Johannes Kepler University Linz, Altenberger Stra\u00dfe 69, 4040 Linz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"100220","DOI":"10.1016\/j.clema.2024.100220","article-title":"The world of plastic waste: A review","volume":"11","author":"Ratnayake","year":"2024","journal-title":"Clean. 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