Some Physical Properties of Heat-Treated Paulownia (Paulownia elongata) Wood

Abstract

The aim of this study was to determine the changes in physical properties of Paulownia (Paulownia elongata) wood, a fast-growing species, during heat treatment at three different temperatures (160, 180, and 200°C) and durations (3, 5, and 7 h). After heat treatment, changes in swelling, density, color, and equilibrium moisture content at 35, 65, and 85% RH were investigated. The results indicated that the minimum and maximum decrease swelling ratios were 6–46% for tangential, 4–32% for radial, and 12–64% for longitudinal. The equilibrium moisture contents were 1–26% for 35% RH, 1–33% for 65% RH, and 1–38% for 85 RH, respectively; the density of air-dried and oven-dried samples decreased by 1–16% and 1.5–15%, respectively, and color changes values (L∗) were 10–40%.

Keywords:

• Heat treatment
• Paulownia
• Paulownia elongata
• Physical properties
• Wood

Notes

X: Average, ±s: Standard deviation, V: Coefficient of variation.

Homogeneity groups: Same letters in each column indicate that there is no statistical difference between the samples according to the Duncan's multiply range test at p < 0.05. Comparisons were done between the each control and test. Thirty replicates were used in each test. All data in variance and one-way ANOVA tests were done at a confidence level of p < 0.05 (95%).