{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,30]],"date-time":"2026-06-30T04:49:23Z","timestamp":1782794963565,"version":"3.54.5"},"reference-count":62,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2025,9,20]],"date-time":"2025-09-20T00:00:00Z","timestamp":1758326400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Secretariat of Science, Humanities, Technology and Innovation (SECIHTI)","award":["549489"],"award-info":[{"award-number":["549489"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>The C=C double bond is a typical feature in biodiesel components associated with their physicochemical behaviors, including metal degradation. In this work, copper was exposed to the gas-phase atmospheres of Methyl Hexanoate (MH) at 145 \u00b0C and 25% Methyl Trans-3-Hexenoate in Methyl Hexanoate (MT3H in MH) at 158 \u00b0C during 1000 h, representing saturated and unsaturated thermal degradation environments of biodiesel surrogates. FTIR, 1H NMR, and GC-MS were used to characterize the chemical changes in the gas-phase atmospheres, whereas SEM allowed us to inspect the copper surfaces. Weight loss assays enabled the estimation of corrosion rates for copper exposed to HM and MT3H in MH atmospheres of 3.81 \u00b1 1.27 and 5.08 \u00b1 1.27 \u03bcm\/year, respectively. Electrochemical measurements (linear polarization resistance (LPR) and electrochemical impedance spectroscopy (EIS)) were used to evaluate the corrosion behavior of copper using aqueous extracts of condensed compounds from gas-phase degraded environments. Our electrochemical results indicate that similar corrosion processes occur in both extracts, remaining nearly unchanged with increasing exposure time. A porous layer of corrosion products on copper revealed that it is more active in the products generated with the MT3H in MH extract, suggesting the significant impact of the C=C bond on copper deterioration.<\/jats:p>","DOI":"10.3390\/ma18184395","type":"journal-article","created":{"date-parts":[[2025,9,22]],"date-time":"2025-09-22T11:18:16Z","timestamp":1758539896000},"page":"4395","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Corrosion on Copper Induced by Biodiesel Surrogates in the Gas Phase: The Effect of the C=C Double Bond"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8160-9712","authenticated-orcid":false,"given":"Fabiola","family":"Vergara-Juarez","sequence":"first","affiliation":[{"name":"Departamento de Ingenier\u00eda Qu\u00edmica y Bioqu\u00edmica, Tecnol\u00f3gico Nacional de M\u00e9xico\/Instituto Tecnol\u00f3gico de Zacatepec, Calzada Tecnol\u00f3gico 27, Zacatepec 62780, Morelos, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emilio","family":"Hernandez-Medina","sequence":"additional","affiliation":[{"name":"Departamento de Ingenier\u00eda Qu\u00edmica y Bioqu\u00edmica, Tecnol\u00f3gico Nacional de M\u00e9xico\/Instituto Tecnol\u00f3gico de Zacatepec, Calzada Tecnol\u00f3gico 27, Zacatepec 62780, Morelos, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6943-3926","authenticated-orcid":false,"given":"Jesus","family":"Porcayo-Calderon","sequence":"additional","affiliation":[{"name":"Departamento de Ingenier\u00eda Qu\u00edmica y Metalurgia, Universidad de Sonora, Hermosillo 83000, Sonora, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Macdiel Emilio","family":"Acevedo-Quiroz","sequence":"additional","affiliation":[{"name":"Departamento de Ingenier\u00eda Qu\u00edmica y Bioqu\u00edmica, Tecnol\u00f3gico Nacional de M\u00e9xico\/Instituto Tecnol\u00f3gico de Zacatepec, Calzada Tecnol\u00f3gico 27, Zacatepec 62780, Morelos, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7230-9715","authenticated-orcid":false,"given":"Jose Trinidad","family":"Perez-Quiroz","sequence":"additional","affiliation":[{"name":"Instituto Mexicano del Transporte, Km. 12 Carretera Estatal No. 431, \u201cEl Colorado-Galindo\u201d, San Fandilla, Pedro Escobedo 76703, Queretaro, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0049-6539","authenticated-orcid":false,"given":"Alfredo","family":"Quinto-Hernandez","sequence":"additional","affiliation":[{"name":"Departamento de Ingenier\u00eda Qu\u00edmica y Bioqu\u00edmica, Tecnol\u00f3gico Nacional de M\u00e9xico\/Instituto Tecnol\u00f3gico de Zacatepec, Calzada Tecnol\u00f3gico 27, Zacatepec 62780, Morelos, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"72","DOI":"10.1038\/scientificamerican0200-72","article-title":"Capturing greenhouse gases","volume":"282","author":"Herzog","year":"2000","journal-title":"Sci. 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