This paper deals with the effect of synthetic and natural flame retardants on flammability characteristics and chemical changes in thermally treated meranti wood (Shorea spp.). The basic chemical composition (extractives, lignin, holocellulose, cellulose, and hemicelluloses) was evaluated to clarify the relationships of temperature modifications (160 °C, 180 °C, and 210 °C) and incineration for 600 s. Weight loss, burning speed, the maximum burning rate, and the time to reach the maximum burning rate were evaluated. Relationships between flammable properties and chemical changes in thermally modified wood were evaluated with the Spearman correlation. The thermal modification did not confirm a positive contribution to the flammability and combustion properties of meranti wood. The effect of the synthetic retardant on all combustion properties was significantly higher compared to that of the natural retardant.

Department of Wood Processing and Biomaterials Faculty of Forestry and Wood Sciences Czech University of Life Sciences Prague Kamýcká 1176 Praha 6 Suchdol 16521 Prague Czech Republic

Faculty of Wood Sciences and Technology Technical University in Zvolen T G Masaryka 24 960 01 Zvolen Slovakia

School of Civil Engineering Southeast University Nanjing 211189 China

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