{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,24]],"date-time":"2026-10-24T15:19:03Z","timestamp":1792855143649,"version":"4.5.0"},"reference-count":46,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2021,5,29]],"date-time":"2021-05-29T00:00:00Z","timestamp":1622246400000},"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>Tree bark is a by-product of the timber industry available in large amounts, considering that approximately 10% of the volume of a tree stem is bark. Bark is used primarily for low-value applications such as heat generation or as mulch. To the best of our knowledge, this study is the first one that scrutinises thermal insulation panels made from spruce bark fibres with different densities and fibre lengths manufactured in a wet process. The insulation boards with densities between 160 and 300 kg\/m3 were self-bonded. Internal bond, thermal conductivity, and dimensional stability (thickness swelling and water absorption), together with formaldehyde content, were analysed. The thermal properties of the boards were directly correlated with the density and reached about 0.044 W\/m*K, while the internal bond was rather influenced by the fibre length and was relatively low (on average 0.07 N\/mm2). The water absorption was high (from 55% to 380%), while the thickness swelling remained moderate (up to 23%). The results of this study have shown that widely available bark residues can be successfully utilised as an innovative raw material for efficient eco-friendly thermal insulation products.<\/jats:p>","DOI":"10.3390\/polym13111799","type":"journal-article","created":{"date-parts":[[2021,5,31]],"date-time":"2021-05-31T03:45:29Z","timestamp":1622432729000},"page":"1799","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":45,"title":["Binderless Thermal Insulation Panels Made of Spruce Bark Fibres"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6368-2227","authenticated-orcid":false,"given":"Jakob","family":"G\u00f6\u00dfwald","sequence":"first","affiliation":[{"name":"Forest Products Technology and Timber Construction Department, Salzburg University of Applied Sciences, Markt 136a, 5431 Kuchl, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0622-6038","authenticated-orcid":false,"given":"Marius-C\u0103t\u0103lin","family":"Barbu","sequence":"additional","affiliation":[{"name":"Forest Products Technology and Timber Construction Department, Salzburg University of Applied Sciences, Markt 136a, 5431 Kuchl, Austria"},{"name":"Faculty of Furniture Design and Wood Engineering, Transilvania University of Brasov, B-dul. Eroilor nr. 29, 500036 Brasov, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexander","family":"Petutschnigg","sequence":"additional","affiliation":[{"name":"Forest Products Technology and Timber Construction Department, Salzburg University of Applied Sciences, Markt 136a, 5431 Kuchl, Austria"},{"name":"Institute of Wood Technology and Renewable Materials, University of Natural Resources and Life Sciences (BOKU), Konrad Lorenz-Stra\u00dfe 24, 3340 Tulln, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2979-5893","authenticated-orcid":false,"given":"Eugenia Mariana","family":"Tudor","sequence":"additional","affiliation":[{"name":"Forest Products Technology and Timber Construction Department, Salzburg University of Applied Sciences, Markt 136a, 5431 Kuchl, Austria"},{"name":"Faculty of Furniture Design and Wood Engineering, Transilvania University of Brasov, B-dul. Eroilor nr. 29, 500036 Brasov, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"7859","DOI":"10.15376\/biores.11.3.Pasztory","article-title":"The utilization of tree bark","volume":"11","author":"Gorbacheva","year":"2016","journal-title":"Bioresources"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"303","DOI":"10.1016\/j.indcrop.2008.03.006","article-title":"Chemical constituents and physical properties of guayule wood and bark","volume":"28","author":"Chow","year":"2008","journal-title":"Ind. Crop. Prod."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"726","DOI":"10.1016\/j.biotechadv.2017.07.007","article-title":"Valorisation of softwood bark through extraction of utilizable chemicals. A review","volume":"35","author":"Jablonsky","year":"2017","journal-title":"Biotechnol. 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