WOOD RESEARCH Volume 71, Number 2, 2026
Martina Hladová, JOZEF MARTINKA, PETER RANTUCH, LENKA BLINOVÁ, PETER GOGOLA, IGOR WACHTER, TOMÁŠ ŠTEFKO, and GEORGE I. MANTANIS

In situ synthesis of Mg-Al Layered Double Hydroxides in wood: a novel approach for Enhanced fire performance

This study presents a modified approach for enhancing the fire performance of white poplar wood (Populus alba L.) through the in situ formation of MgAl layered double hydroxides (LDHs) within the wood structure. The treated wood exhibited significantly improved fire properties. The limiting oxygen index (LOI) increased from 19% to 45%, while cone calorimetry results showed reductions of approximately 65% in peak heat release rate (HRR), 58% in total heat release (THR), 80% in maximum average rate of heat emission (MARHE), and 80% in total smoke production (TSP) compared to untreated poplar wood. The enhanced fire performance is attributed to the formation of a protective char layer and the presence of inorganic residues derived from LDH decomposition, which influences the thermal degradation and combustion behaviour of the wood. The results demonstrate that this simple modification approach provides an effective method for improving the fire performance and smoke suppression properties of fast-growing wood species.

WOOD RESEARCH Volume 67, Number 6, 2022
Peter Godovčin, JOZEF MARTINKA, PETER RANTUCH, Martina Hladová, JURAJ KOPÚNEK, Mária Otajovičová, and Mária Zuzana Bednáriková

Impact of temperature and ultraviolet radiation on changes of colour of fir and spruce wood

This study deals with the investigation of impact of temperature and ultraviolet (UV) radiation on spruce wood (Picea abies (L.) H. Karst.) and fir wood (Abies alba Mill.) colour changes. Samples of investigated woods species were loaded by temperatures of 110, 130, and 150°C and UV radiation (with 253.7 nm wavelength and 40 W m-2 intensity) during 72, 168, 336 and 672 hours. Colour changes were evaluated in the CIE Lab colour space. The neural network for prediction of both colour coordinates and total colour difference of spruce and fir wood was trained by data regarding exposure conditions (temperature, UV radiation and time) and by obtained results. Coefficient of determination (R2) of the neural network was above 0.99 for training, validation and testing. Average colour coordinates (± standard deviation) of the spruce and fir wood before exposure were L* = 80.08 ± 3.70, a* = 7.55 ± 2.13, b* = 21.56 ± 1.79, L* = 80.46 ± 1.91, a* = 6.84 ± 0.97, and b* = 18.90 ± 1.26, resp. Total colour differences after thermal loading were in the interval from ΔEab* = 3.76 ± 1.95 (spruce wood at 110°C) to ΔEab* = 45.37±1.46 (fir wood at 150°C). Total colour differences of both wood species exposed by UV radiation were approximately in intervals from ΔEab* = 12 to 13 (after 72 h) up to ΔEab* = 16 to 20 (after 168 to 672 h). Obtained results proven that both temperature and UV radiation have significant impact on the colour changes of the investigated woods.