Transparent Wood Produced by Nitrate-Alkaline Delignification and its Properties
Kateřina Hájková* and Tomáš Holeček
ABSTRACT
Nowadays, emphasis is placed on the use of environmentally friendly materials both in terms of construction and the application of protective equipment. For this reason, dealing with wood products such as transparent wood is advisable, even though its production requires chemicals. Environmental friendliness is the main reason for producing transparent wood using the nitrate-alkali method. Transparent wood is mainly used indoors as a design element. This article deals with producing transparent wood from beech (Fagus sylvatica) and its impact on optical, mechanical properties, and fire resistance. Among the mechanical properties, the compressive strength was evaluated. The optical properties were very positive, especially regarding opacity, which had a zero value. Regarding fire resistance, maximum average rate of heat emission (MARHE) and limiting oxygen index (LOI) were evaluated, and from these values, the transparent wood does not reach the qualities of untreated wood. In the case of MARHE, the value for transparent wood was 2.6× higher than for beech wood, which was 208.38 kW∙m-2. The LOI was reduced from 24.55% for beech to 18.75% for thorny transparent wood. This research's results serve to understand better the production of transparent wood, which can be used in its application.
