{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,24]],"date-time":"2026-04-24T13:24:10Z","timestamp":1777037050884,"version":"3.51.4"},"reference-count":54,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2025,2,25]],"date-time":"2025-02-25T00:00:00Z","timestamp":1740441600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Funda\u00e7\u00e3o La Caixa and Minist\u00e9rio para Ci\u00eancia e Tecnologia\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>This study explores the valorization of non-commercial chestnut waste from the Portuguese chestnut industry to develop biocomposites. The composites were obtained by hot compression molding, and a Box\u2013Behnken Design model was employed to optimize the mechanical, thermal, and water resistance properties of the chestnut-based composite, using fruit and shell fibers, respectively, as the polymeric matrix and reinforcement agent. The optimal formulation, comprising 70% chestnut, no glycerol, a molding temperature of 120 \u00b0C, and applying a pressure of 2.93 MPa for 30 min, achieved a Flexural Strength of 9.00 MPa and a Flexural Modulus of 950 MPa. To enhance water resistance, shellac was added as a natural hydrophobic coating. Water interaction tests indicated that shellac-treated biocomposites exhibited superior water resistance, absorbing approximately two times less water than those containing glycerol or untreated samples. Thermal analysis revealed that glycerol acted as a plasticizer, improving flexibility and reducing the glass transition temperature. Additionally, the chestnut-based biocomposite demonstrated an out-of-plane thermal conductivity of 0.79 W\/m\u00b7K, categorizing it as a thermal insulator. The final prototype application was a candle holder, showcasing the potential for the practical and sustainable use of chestnut-based composite. This research highlights the potential for chestnut waste to be repurposed into eco-friendly products, offering an alternative to conventional plastics and contributing to a circular economy.<\/jats:p>","DOI":"10.3390\/polym17050616","type":"journal-article","created":{"date-parts":[[2025,2,25]],"date-time":"2025-02-25T12:01:17Z","timestamp":1740484877000},"page":"616","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Eco-Friendly Biocomposites from Chestnut Waste: Production, Optimization, Characterization, and Application"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9857-9476","authenticated-orcid":false,"given":"Sim\u00e3o B.","family":"Silva","sequence":"first","affiliation":[{"name":"REQUIMTE\/LAQV, ISEP, Polytechnic of Porto, Rua Dr. Ant\u00f3nio Bernardino de Almeida 431, 4249-015 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2499-6143","authenticated-orcid":false,"given":"Olga M.","family":"Freitas","sequence":"additional","affiliation":[{"name":"REQUIMTE\/LAQV, ISEP, Polytechnic of Porto, Rua Dr. Ant\u00f3nio Bernardino de Almeida 431, 4249-015 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0301-6182","authenticated-orcid":false,"given":"Elsa F.","family":"Vieira","sequence":"additional","affiliation":[{"name":"REQUIMTE\/LAQV, ISEP, Polytechnic of Porto, Rua Dr. Ant\u00f3nio Bernardino de Almeida 431, 4249-015 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-2450-5667","authenticated-orcid":false,"given":"Am\u00e1lia","family":"Gomes","sequence":"additional","affiliation":[{"name":"CICECO\u2014Aveiro Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-5765-1248","authenticated-orcid":false,"given":"Ana R.","family":"Carreiras","sequence":"additional","affiliation":[{"name":"M4S\u2014Materials for Sustainability, ISEP, Polytechnic of Porto, 4249-015 Porto, Portugal"}]},{"given":"Diogo C.","family":"Moreira","sequence":"additional","affiliation":[{"name":"M4S\u2014Materials for Sustainability, ISEP, Polytechnic of Porto, 4249-015 Porto, Portugal"}]},{"given":"P\u00faria","family":"Esfandiari","sequence":"additional","affiliation":[{"name":"M4S\u2014Materials for Sustainability, ISEP, Polytechnic of Porto, 4249-015 Porto, Portugal"}]},{"given":"Jo\u00e3o F.","family":"Silva","sequence":"additional","affiliation":[{"name":"M4S\u2014Materials for Sustainability, ISEP, Polytechnic of Porto, 4249-015 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3924-776X","authenticated-orcid":false,"given":"Cristina","family":"Delerue-Matos","sequence":"additional","affiliation":[{"name":"REQUIMTE\/LAQV, ISEP, Polytechnic of Porto, Rua Dr. Ant\u00f3nio Bernardino de Almeida 431, 4249-015 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3472-849X","authenticated-orcid":false,"given":"Valentina F.","family":"Domingues","sequence":"additional","affiliation":[{"name":"REQUIMTE\/LAQV, ISEP, Polytechnic of Porto, Rua Dr. Ant\u00f3nio Bernardino de Almeida 431, 4249-015 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,2,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"19343","DOI":"10.1021\/acsomega.1c02760","article-title":"Plastic Pollution: A Perspective on Matters Arising: Challenges and Opportunities","volume":"6","author":"Iroegbu","year":"2021","journal-title":"ACS Omega"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Mohanty, A.K., Misra, M., and Drzal, L.T. 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