{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,24]],"date-time":"2026-02-24T20:57:55Z","timestamp":1771966675663,"version":"3.50.1"},"reference-count":22,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2024,11,8]],"date-time":"2024-11-08T00:00:00Z","timestamp":1731024000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"CICECO-Aveiro Institute of Materials","award":["UIDB\/50011\/2020"],"award-info":[{"award-number":["UIDB\/50011\/2020"]}]},{"name":"CICECO-Aveiro Institute of Materials","award":["UIDP\/50011\/2020"],"award-info":[{"award-number":["UIDP\/50011\/2020"]}]},{"name":"CICECO-Aveiro Institute of Materials","award":["LA\/P\/0006\/2020"],"award-info":[{"award-number":["LA\/P\/0006\/2020"]}]},{"name":"FEDER","award":["UIDB\/50011\/2020"],"award-info":[{"award-number":["UIDB\/50011\/2020"]}]},{"name":"FEDER","award":["UIDP\/50011\/2020"],"award-info":[{"award-number":["UIDP\/50011\/2020"]}]},{"name":"FEDER","award":["LA\/P\/0006\/2020"],"award-info":[{"award-number":["LA\/P\/0006\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sustainability"],"abstract":"<jats:p>Polyamides (PAs) are extensively utilized across various applications, yet the accumulation of PA residues presents significant ecological and environmental challenges. Given that a substantial portion of fishing nets are composed of nylon, a type of PA, this material\u2019s disposal raises environmental concerns impacting marine life and the global ecosystem. Therefore, to enhance sustainability, they could be collected and recycled. This study introduces a method for the chemical recycling of PA waste using hydrochloric acid (HCl). Through solvolysis, a PA was depolymerized, and the effect of various reaction conditions on the depolymerization yield was analyzed, being the best conditions established in this work (100 \u00b0C, 4 h, and an HCl\/PA ratio of 11:1, wt.wt\u22121). Next, a novel separation methodology was employed to isolate recycled products from salts formed during neutralization. Subsequently, these recycled products were incorporated as a partial substitute (up to 10% wt.wt\u22121) for a conventional PA in a new material production. The results indicate that the presence of recycled products enhances material stiffness due to crystallinity differences compared to the virgin matrix. In turn, the introduction of lower-molecular-weight species increases the materials\u2019 glass transition temperature (Tg) and their melt flow index (MFI). This research underscores a sustainable pathway for PA recycling aligned with circular economy principles, contributing positively to environmental conservation efforts.<\/jats:p>","DOI":"10.3390\/su16229725","type":"journal-article","created":{"date-parts":[[2024,11,8]],"date-time":"2024-11-08T06:05:41Z","timestamp":1731045941000},"page":"9725","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Solvolysis of Nylon: A Pathway to Sustainable Recycling and Circular Economy"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1865-098X","authenticated-orcid":false,"given":"Nuno","family":"Gama","sequence":"first","affiliation":[{"name":"CICECO\u2014Aveiro Institute of Materials and Department of Chemistry, University of Aveiro, Campus Santiago, 3810-193 Aveiro, Portugal"}]},{"given":"J\u00e9ssica","family":"Ara\u00fajo","sequence":"additional","affiliation":[{"name":"CICECO\u2014Aveiro Institute of Materials and Department of Chemistry, University of Aveiro, Campus Santiago, 3810-193 Aveiro, Portugal"}]},{"given":"Bruno","family":"Godinho","sequence":"additional","affiliation":[{"name":"CICECO\u2014Aveiro Institute of Materials and Department of Chemistry, University of Aveiro, Campus Santiago, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1785-4048","authenticated-orcid":false,"given":"Artur","family":"Ferreira","sequence":"additional","affiliation":[{"name":"CICECO\u2014Aveiro Institute of Materials and \u00c1gueda School of Technology and Management, Rua Comandante Pinho e Freitas, No. 28, 3750-127 \u00c1gueda, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6462-8679","authenticated-orcid":false,"given":"Ana","family":"Barros-Timmons","sequence":"additional","affiliation":[{"name":"CICECO\u2014Aveiro Institute of Materials and Department of Chemistry, University of Aveiro, Campus Santiago, 3810-193 Aveiro, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2024,11,8]]},"reference":[{"key":"ref_1","unstructured":"Fried, J.R. 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