{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,6]],"date-time":"2026-03-06T02:32:38Z","timestamp":1772764358505,"version":"3.50.1"},"reference-count":35,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2023,11,13]],"date-time":"2023-11-13T00:00:00Z","timestamp":1699833600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"A smart and eco-friendly adhesively bonded structure for the next generation mobility platforms","doi-asserted-by":"publisher","award":["PTDC\/EME-EME\/6442\/2020"],"award-info":[{"award-number":["PTDC\/EME-EME\/6442\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"A smart and eco-friendly adhesively bonded structure for the next generation mobility platforms","doi-asserted-by":"publisher","award":["CEECIND\/03276\/2018"],"award-info":[{"award-number":["CEECIND\/03276\/2018"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"A smart and eco-friendly adhesively bonded structure for the next generation mobility platforms","doi-asserted-by":"publisher","award":["2022.12426.BD"],"award-info":[{"award-number":["2022.12426.BD"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Portuguese Foundation for Science and Technology (FCT)","doi-asserted-by":"publisher","award":["PTDC\/EME-EME\/6442\/2020"],"award-info":[{"award-number":["PTDC\/EME-EME\/6442\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Portuguese Foundation for Science and Technology (FCT)","doi-asserted-by":"publisher","award":["CEECIND\/03276\/2018"],"award-info":[{"award-number":["CEECIND\/03276\/2018"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Portuguese Foundation for Science and Technology (FCT)","doi-asserted-by":"publisher","award":["2022.12426.BD"],"award-info":[{"award-number":["2022.12426.BD"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>This study investigates a sustainable alternative for composites and adhesives in high-performance industries like civil and automotive. This study pioneers the development and application of a new methodology to characterize a bio-based, zero-thickness adhesive. This method facilitates precise measurements of the adhesive\u2019s strength and fracture properties under zero-thickness conditions. The research also encompasses the characterization of densified pine wood, an innovative wood product distinguished by enhanced mechanical properties, which is subsequently compared to natural pine wood. We conducted a comprehensive characterization of wood\u2019s strength properties, utilizing dogbone-shaped samples in the fiber direction, and block specimens in the transverse direction. Butt joints were employed for adhesive testing. Mode I fracture properties were determined via compact tension (CT) and double cantilever beam (DCB) tests for wood and adhesive, respectively, while mode II response was assessed through end-loaded split (ELS) tests. The densification procedure, encompassing chemical and mechanical processes, was a focal point of the study. Initially, wood was subjected to acid boiling to remove the wood matrix, followed by the application of pressure to enhance density. As a result, wood density increased by approximately 100 percent, accompanied by substantial improvements in strength and fracture energy along the fiber direction by about 120 percent. However, it is worth noting that due to the delignification nature of the densification method, properties in the transverse direction, mainly reliant on the lignin matrix, exhibited compromises. Also introduced was an innovative technique to evaluate the bio-based adhesive, applied as a zero-thickness layer. The results from this method reveal promising mechanical properties, highlighting the bio-based adhesive\u2019s potential as an eco-friendly substitute for synthetic adhesives in the wood industry.<\/jats:p>","DOI":"10.3390\/ma16227147","type":"journal-article","created":{"date-parts":[[2023,11,14]],"date-time":"2023-11-14T02:20:37Z","timestamp":1699928437000},"page":"7147","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Characterization of Densified Pine Wood and a Zero-Thickness Bio-Based Adhesive for Eco-Friendly Structural Applications"],"prefix":"10.3390","volume":"16","author":[{"given":"Shahin","family":"Jalali","sequence":"first","affiliation":[{"name":"Institute of Science and Innovation in Mechanical and Industrial Engineering (INEGI), Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]},{"given":"Catarina da Silva Pereira","family":"Borges","sequence":"additional","affiliation":[{"name":"Institute of Science and Innovation in Mechanical and Industrial Engineering (INEGI), Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1933-0865","authenticated-orcid":false,"given":"Ricardo Jo\u00e3o Camilo","family":"Carbas","sequence":"additional","affiliation":[{"name":"Institute of Science and Innovation in Mechanical and Industrial Engineering (INEGI), Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"},{"name":"Departamento de Engenharia Mec\u00e2nica, Faculdade de Engenharia, Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]},{"given":"Eduardo Andr\u00e9 de Sousa","family":"Marques","sequence":"additional","affiliation":[{"name":"Departamento de Engenharia Mec\u00e2nica, Faculdade de Engenharia, Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]},{"given":"Jo\u00e3o Carlos Moura","family":"Bordado","sequence":"additional","affiliation":[{"name":"Centro de Recursos Naturais E Ambiennte (CERENA), Instituto Superior T\u00e9cnico, University of Lisbon, 1049-001 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3272-4591","authenticated-orcid":false,"given":"Lucas Filipe Martins","family":"da Silva","sequence":"additional","affiliation":[{"name":"Departamento de Engenharia Mec\u00e2nica, Faculdade de Engenharia, Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2023,11,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"989","DOI":"10.1289\/ehp.1003220","article-title":"Most plastic products release estrogenic chemicals: A potential health problem that can be solved","volume":"119","author":"Yang","year":"2011","journal-title":"Environ. 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