NEAR INFRARED SPECTROSCOPY ASSAY FOR THERMAL TREATMENT OF WOOD

Katsuya MITSUI
Dr. - Gifu Prefectural Human Life Technology Research Institute
Address: 1554 Yamada, Takayama 506-0058, Japan
E-mail: mitsui@wood.rd.pref.gifu.jp

Tetsuya INAGAKI
Nagoya University, Graduate School of Bioagricultural Science
Address: Furo-cho, Chikusa Nagoya 464-8601, Japan
E-mail: tetsuyaina@hotmail.com

Satoru TSUCHIKAWA
Prof.Dr. - Nagoya University, Graduate School of Bioagricultural Science
Address: Furo-cho, Chikusa Nagoya 464-8601, Japan
E-mail: st3842@nuagr1.agr.nagoya-u.ac.jp

Abstract: This paper deals the evaluation of thermally treated wood by near infrared (NIR) spectroscopy. In the NIR second derivative spectrum, the peak at 6913 cm-1, which has not been reported, appeared with the procession of heat treatment. It was guessed that it should be assigned to phenolic hydroxyl group originated from lignin because the acetylated wood did not have any peak at 6913 cm-1 in the second derivative spectrum. Moreover, the NIR spectra in the region of hydroxyl groups (7200 - 6100 cm-1) was separated by Gauss - Newton method, and the changes in the ratio of peak area after thermal treatment to that before treatment was discussed. As a result, it was guessed that the hydroxyl groups in cellulose degraded those in amorphous, in semi-crystalline, and in crystalline region, in that order.

Key words: hydroxyl groups, near infrared spectroscopy, thermal treatment.

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