{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,30]],"date-time":"2026-01-30T04:46:44Z","timestamp":1769748404437,"version":"3.49.0"},"reference-count":29,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,1,29]],"date-time":"2026-01-29T00:00:00Z","timestamp":1769644800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union\u2019s Horizon Europe research and innovation program","award":["101091668"],"award-info":[{"award-number":["101091668"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Fiber-reinforced polymer composites (FRPCs) are increasingly used in construction due to their high performance and low environmental footprint. However, their widespread adoption has raised concerns over end-of-life management, particularly under European regulations mandating high recycling rates for construction and demolition waste (CDW). This study evaluates different systems for the chemical recycling of FRPCs through microwave (MW)-assisted solvolysis using green solvents, including deep eutectic solvents (DESs) and biobased acetic acid. The process targets thermoset resin depolymerization while preserving fiber integrity, operating at reduced temperatures (\u2264230 \u00b0C) and lower energy demand than conventional techniques, such as pyrolysis. A systematic experimental design was applied to CDW-derived polyester composites and extended to industrial epoxy and vinyl ester composites. Among the tested solvents, glacial acetic acid + ZnCl2 (5 wt.%), achieved the highest degradation efficiency, exceeding 94% in small-scale trials and maintaining over 78% upon upscaling. Recovered fibers showed moderate property retention, with tensile strength and elongation losses of ~30% and ~45% for infusion-based epoxy composites, while those from pultrusion-based epoxy composites exhibited 16\u201319% and retained similar properties to the virgin material, respectively. The method facilitates fiber recovery with limited degradation and aligns with circular economy principles through solvent reuse and minimizing environmental impact.<\/jats:p>","DOI":"10.3390\/polym18030362","type":"journal-article","created":{"date-parts":[[2026,1,29]],"date-time":"2026-01-29T14:52:36Z","timestamp":1769698356000},"page":"362","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Microwave-Assisted Bio-Based Chemical Recycling of Fiber-Reinforced Composites from Construction and Demolition Waste"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0009-0008-6927-6589","authenticated-orcid":false,"given":"Gonzalo","family":"Murillo-Ciordia","sequence":"first","affiliation":[{"name":"CIRCE\u2014Technology Centre for Energy Resources and Consumption, Parque Empresarial Dinamiza, Av. Ranillas 3D, 1st Floor, 50018 Zaragoza, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cecilia","family":"Chaine","sequence":"additional","affiliation":[{"name":"CIRCE\u2014Technology Centre for Energy Resources and Consumption, Parque Empresarial Dinamiza, Av. Ranillas 3D, 1st Floor, 50018 Zaragoza, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"100742","DOI":"10.1016\/j.jobe.2019.100742","article-title":"Recycled construction and demolition waste as a possible source of materials for composite manufacturing","volume":"24","author":"Sormunen","year":"2019","journal-title":"J. Build. 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