Effect of Thermal Treatment on Fracture Properties and Adsorption Properties of Spruce Wood

Materials

Koji Murata¹  Yasuhiro Watanabe² 

[1] Division of Forest and Biomaterials Science, Graduate School of Agriculture, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan; E-Mail:;Canon Inc., Ota-ku, Tokyo 146-8501, Japan; E-Mail:

关键词: wood;    thermal treatment;    fracture energy;    strain-softening behavior;    fiber saturation point;    adsorption isotherm;   

DOI  :  10.3390/ma6094186

来源: mdpi

【 摘 要 】

The effect of thermal treatment on spruce is examined by analyzing the fracture and hygroscopic properties. Specimens were heated at temperatures within the range 120–200 °C for 1 h. Fracture energy was measured using a single-edge notched bending test and the strain-softening index was estimated by dividing the fracture energy by the maximum load. Adsorption properties were estimated using adsorption isotherms. Fiber saturation points (FSPs) were estimated by extrapolating the moisture adsorption isotherm curve. Langmuir’s adsorption coefficient and number of adsorption sites were obtained using Langmuir’s theory and the Hailwood-Horrobin theory, respectively. The fracture energy, FSPs, and specimen weights decreased at temperatures higher than 150 °C, but the critical point for the strain-softening index and the number of adsorption sites was shown to be 180 °C. We hypothesize that the fracture energy and FSP depend on the chemical structure of the cell wall, whereas the strain-softening behavior may be influenced by the number of adsorption sites, and in turn the number of hydrogen bonds in hemicellulose.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.