{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,28]],"date-time":"2026-01-28T22:48:29Z","timestamp":1769640509287,"version":"3.49.0"},"reference-count":56,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2023,2,7]],"date-time":"2023-02-07T00:00:00Z","timestamp":1675728000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Two epoxy resins with different viscosities were enhanced up to 1 wt.%, applying a simple method with carbon nanofibers (CNFs). These were characterized in terms of static bending stress, stress relaxation, and creep tests. In bending, the contents of 0.5 wt.% and 0.75 wt.% of CNFs on Ebalta and Sicomin epoxies, respectively, promote higher relative bending stress (above 11.5% for both) and elastic modulus (13.1% for Sicomin and 16.2% for Ebalta). This highest bending stress and modulus occurs for the lower viscosity resin (Ebalta) due to its interfacial strength and dispersibility of the fillers. Creep behaviour and stress relaxation for three stress levels (20, 50, and 80 MPa) show the benefits obtained with the addition of CNFs, which act as a network that contributes to the immobility of the polymer chains. A long-term experiment of up to 100 h was successfully applied to fit the Kohlrausch\u2013Williams\u2013Watts (KWW) and Findley models to stress relaxation and creep behaviour with very good accuracy.<\/jats:p>","DOI":"10.3390\/polym15040821","type":"journal-article","created":{"date-parts":[[2023,2,8]],"date-time":"2023-02-08T04:57:41Z","timestamp":1675832261000},"page":"821","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Effect of Carbon Nanofibers on the Viscoelastic Response of Epoxy Resins"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9026-5966","authenticated-orcid":false,"given":"Paulo","family":"Santos","sequence":"first","affiliation":[{"name":"Centre for Mechanical and Aerospace Science and Technologies (C-MAST), University of Beira Interior, 6201-001 Covilh\u00e3, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2100-7223","authenticated-orcid":false,"given":"Ab\u00edlio P.","family":"Silva","sequence":"additional","affiliation":[{"name":"Centre for Mechanical and Aerospace Science and Technologies (C-MAST), University of Beira Interior, 6201-001 Covilh\u00e3, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5203-3670","authenticated-orcid":false,"given":"Paulo N. B.","family":"Reis","sequence":"additional","affiliation":[{"name":"University of Coimbra, CEMMPRE, Department of Mechanical Engineering, 3030-788 Coimbra, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.jiec.2015.03.026","article-title":"Synthesis and Application of Epoxy Resins: A Review","volume":"29","author":"Jin","year":"2015","journal-title":"J. Ind. Eng. Chem."},{"key":"ref_2","first-page":"1","article-title":"Epoxy Resins","volume":"Volume 11","author":"Higgins","year":"2018","journal-title":"Kanerva\u2019s Occupational Dermatology"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"198","DOI":"10.3221\/IGF-ESIS.55.15","article-title":"Mechanical Characterization of Different Epoxy Resins Enhanced with Carbon Nanofibers","volume":"15","author":"Maceiras","year":"2020","journal-title":"Frat. 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