{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,13]],"date-time":"2026-02-13T06:56:37Z","timestamp":1770965797985,"version":"3.50.1"},"reference-count":27,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2022,2,23]],"date-time":"2022-02-23T00:00:00Z","timestamp":1645574400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["PTDC\/QUI-OUT\/31884\/2017"],"award-info":[{"award-number":["PTDC\/QUI-OUT\/31884\/2017"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["UIDB00102\/2020"],"award-info":[{"award-number":["UIDB00102\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["UID\/05488\/2018"],"award-info":[{"award-number":["UID\/05488\/2018"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100008530","name":"European Regional Development Fund","doi-asserted-by":"publisher","award":["CENTRO 01-0145-FEDER-031884"],"award-info":[{"award-number":["CENTRO 01-0145-FEDER-031884"]}],"id":[{"id":"10.13039\/501100008530","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Coatings"],"abstract":"<jats:p>Cellulose nanofibrils (CNFs) are nanomaterials with promising properties to be used in food packaging and printed electronics, thus being logical substitutes to petroleum-based polymers, specifically plastics. CNFs can be combined with other materials, such as clay minerals, to form composites, which are environmentally friendly materials, with acceptable costs and without compromising the final properties of the composite material. To produce composite films, two strategies can be used: solvent casting and filtration followed by hot pressing. The first approach is the simplest way to produce films, but the obtained films may present some limitations. In the present work, CNFs produced using enzymatic or TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl radical) oxidation pretreatments, followed by high-pressure homogenization, or only by mechanical treatment (homogenization), were used to produce films by both the available procedures. The films obtained by filtration + hot pressing presented higher tensile strength and Young\u2019s modulus compared with those obtained by solvent casting. In general, a decrease in the values of these mechanical properties of the films and a decrease in elongation at break, with the addition of sepiolite, were also observed. However, for the TEMPO CNF-based films, an improvement in tensile strength could be observed for 10% of the sepiolite content. Furthermore, the time necessary to produce films was largely reduced by employing the filtration procedure. Finally, the water vapour barrier properties of the films obtained by filtration are comparable to the literature values of net CNF films. Thus, this technique demonstrates to be the most suitable to produce CNF-based composite films in a fast way and with improved mechanical properties and suitable gas barrier properties.<\/jats:p>","DOI":"10.3390\/coatings12030303","type":"journal-article","created":{"date-parts":[[2022,2,23]],"date-time":"2022-02-23T09:34:38Z","timestamp":1645608878000},"page":"303","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Composite Films of Nanofibrillated Cellulose with Sepiolite: Effect of Preparation Strategy"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4447-5107","authenticated-orcid":false,"given":"Lu\u00eds","family":"Alves","sequence":"first","affiliation":[{"name":"CIEPQPF, Department of Chemical Engineering, University of Coimbra, Rua S\u00edlvio Lima, P\u00f3lo II, PT-3030-790 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7324-1070","authenticated-orcid":false,"given":"Ana","family":"Ramos","sequence":"additional","affiliation":[{"name":"FibEnTech, Departament of Chemistry, University of Beira Interior, Rua Marqu\u00eas d\u2019\u00c1vila e Bolama, PT-6201-001 Covilh\u00e3, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6084-4553","authenticated-orcid":false,"given":"Maria G.","family":"Rasteiro","sequence":"additional","affiliation":[{"name":"CIEPQPF, Department of Chemical Engineering, University of Coimbra, Rua S\u00edlvio Lima, P\u00f3lo II, PT-3030-790 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3424-548X","authenticated-orcid":false,"given":"Carla","family":"Vitorino","sequence":"additional","affiliation":[{"name":"CQC, Department of Chemistry, University of Coimbra, Rua Larga, PT-3004-535 Coimbra, Portugal"},{"name":"Faculty of Pharmacy, University of Coimbra, PT-3000-548 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4717-6305","authenticated-orcid":false,"given":"Eduardo","family":"Ferraz","sequence":"additional","affiliation":[{"name":"Techn&Art, Polytechnic Institute of Tomar, Quinta do Contador, Estrada da Serra, PT-2300-313 Tomar, Portugal"},{"name":"Geobiotec, Geosciences Department, University of Aveiro, Campus Universit\u00e1rio de Santiago, PT-3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4503-6811","authenticated-orcid":false,"given":"Paulo J. T.","family":"Ferreira","sequence":"additional","affiliation":[{"name":"CIEPQPF, Department of Chemical Engineering, University of Coimbra, Rua S\u00edlvio Lima, P\u00f3lo II, PT-3030-790 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3830-0263","authenticated-orcid":false,"given":"Maria L.","family":"Puertas","sequence":"additional","affiliation":[{"name":"Tolsa, SA, Research & Technology for New Businesses, Ctra. de Madrid a Rivas Jarama, 35, ES-28031 Madrid, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1474-767X","authenticated-orcid":false,"given":"Jos\u00e9 A. F.","family":"Gamelas","sequence":"additional","affiliation":[{"name":"CIEPQPF, Department of Chemical Engineering, University of Coimbra, Rua S\u00edlvio Lima, P\u00f3lo II, PT-3030-790 Coimbra, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,23]]},"reference":[{"key":"ref_1","first-page":"571","article-title":"High oxygen barrier polyethylene films","volume":"25","author":"Ayuso","year":"2017","journal-title":"Polym. Polym. Compos."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"101994","DOI":"10.1016\/j.cis.2019.101994","article-title":"Composites of nanofibrillated cellulose with clay minerals: A review","volume":"272","author":"Alves","year":"2019","journal-title":"Adv. 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