The analysis of thermal transmittance in some types of wood modified using natural wood tannin

The present study aims to analyze changes in coefficient of thermal conductivity (λ) and coefficient of thermal transmittance (U) values following the impregnation of wood material obtained from Pine (Pinus Sylvestris), Sessile Oak (Quercus Petraea) and Chestnut (Castanea Sativa), which are widely used in the field of woodwork industry, using natural tannin solution produced from walnut leaves and outer shell. To this aim, a total of 75 measurement samples consisting of 60 impregnated measurement samples and 15 non- impregnated control samples with 5 wood samples in three different wood categories, which were impregnated at different levels (3-times and 6-times brushing, 4-hour and 8-hour dipping), were prepared. The samples were firstly air-conditioned at a temperature of 20±2 °C and a relative humidity of 65% ± 5, later at 40±2 °C and 35% ± 5 and, finally, at 10±2 °C and 50% ± 5 in order to calculate their λ and U values and determine their thermal properties. In conclusion, when compared with control samples, it was observed that 6-times brushing and 8-hour dipping processes reduced thermal conductivity of the samples by 1,5% and 2,9% (making them non-conducting) respectively and that 8-hour dipping and 6-times brushing processes reduced thermal transmittance (U) by 3,6% and 3,7% respectively, thus making the samples more non-conducting.