Effects of thermal modification on the water resistance and colour stability of wood species from Bosnia and Herzegovina

Hasanagić, Redžo (author), Mujanić, Selma (author), Bahmani, Mohsen (author), Humar, Miha (author)

This study investigates the impact of thermal modification on the water resistance and colour stability of Indigenous wood species from Bosnia and Herzegovina, including Norway spruce (Picea abies), silver fir (Abies alba), oak (Quercus sp.), and walnut (Juglans regia). Thermal modification, conducted in the presence of air, enhanced the hydrophobicity of all tested wood species by reducing their water absorption and limiting their susceptibility to moisture-driven dimensional changes. The modification process also induced notable colour changes, darkening each species in line with the degradation of lignin and other wood constituents. The degree of colour change was observed to increase with higher treatment temperatures, particularly at 210 °C, as measured by the CIE Lab colour system. These findings suggest that thermal modification provides an environmentally friendly method to improve both durability and aesthetic appeal in wood, extending the material’s application range for humid or outdoor environments.

• Language: English
• Keywords: thermal modification, sorption, water resistance, colour change, indigenous wood species
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: BF - Biotechnical Faculty
• Publication status: Published
• Publication version: Version of Record
• Publication date: 01.01.2025
• Year: 2025
• Number of pages: Str. 13-24
• Numbering: Let. 74, št. 1
• PID: 20.500.12556/RUL-169782
• UDC: 630*842
• ISSN on article: 2590-9932
• COBISS.SI-ID: 238973699
• Publication date in RUL: 11.06.2025

Record is a part of a journal

• Title: Les
• Publisher: Biotehniška fakulteta, Oddelek za lesarstvo, Biotehniška fakulteta, Oddelek za lesarstvo, Založba Univerze
• ISSN: 2590-9932
• COBISS.SI-ID: 290940672

Licences

• License: CC BY-SA 4.0, Creative Commons Attribution-ShareAlike 4.0 International
• Link: http://creativecommons.org/licenses/by-sa/4.0/
• Description: This Creative Commons license is very similar to the regular Attribution license, but requires the release of all derivative works under this same license.

Secondary language

• Language: Slovenian
• Title: Vpliv termične modifikacije na odpornost proti navlaževanju in spremembo barve lesa iz Bosne in Hercegovine

Abstract

Ta študija raziskuje vpliv termične modifikacije na vodoodpornost in barvno stabilnost različnih vrst lesa iz Bosne in Hercegovine, vključno z navadno smreko (Picea abies), belo jelko (Abies alba), hrastom (Quercus sp.) in orehom (Juglans regia). Termična modifikacija, izvedena v prisotnosti zraka, je povečala hidrofobnost vseh testiranih lesnih vrst z zmanjšanjem vpojnosti vode in omejitvijo njihove dovzetnosti za spremembe dimenzij zaradi vlage. Postopek modifikacije je povzročil tudi opazne barvne spremembe, pri čemer so vse vrste potemnele zaradi oksidacije lignina in drugih sestavin lesa. Opazili smo, da se stopnja spremembe barve povečuje z višjimi temperaturami modifikacije, zlasti pri 210 °C, na podlagi meritev v skladu s sistemom CIE Lab. Te ugotovitve kažejo, da termična modifikacija zagotavlja okolju prijazno metodo za izboljšanje življenjske dobe in estetske privlačnosti lesa, s čimer se razširi obseg uporabe materiala v vlažnih ali zunanjih okoljih.

• Keywords: termična modifikacija, sorpcija, vodoodpornost, sprememba barve, avtohtone lesne vrste