Effect of heat treatment on the dimensional stability of ash (Fraxinus angustifolia Vahl.) wood

Abstract

The effect of heat treatment on the dimensional stability of ash ( Fraxinus angustifolia  Vahl.) wood Abstract:  In this study, effect of heat treatment on dimensional stability of ash ( Fraxinus angustifolia  Vahl.) woods that naturally grown in Turkey, was investigated. Heat treatment process was applied to ash wood samples at different temperatures (120, 160, 190 and 210 °C) and times (3, 6 and 9 h) in water vapor atmosphere. Water absorption (WA), water repellent effectiveness (WRE), anti-swell effectiveness (ASE, TS 4084) and ATR-FTIR were performed on the test samples. Generally, while the WA decreased with the raise of treatment temperature and times, mean of the WRE and ASE increased. It was determined that the decreases in the absorbance value of the peak belong to the -OH stretching vibration depending on the heat treatment temperature increases. Especially, ASE increased to over 40% with a rapid increase after the three hours application at 190 °C. The highest dimensional stability (58.4%) of ash wood was detected in the highest heat treatment temperature and times (210 °C and 9 h). As a result, it was showed that value and product quality of solid products produced from ash wood with the heat treatment can be improved without use of toxic chemicals. Keywords:  Ash wood, Dimensional stability, ATR-FTIR, Water absorption, water repellent effectiveness Disbudak ( Fraxinus angustifolia  Vahl.) odununun boyutsal stabilizasyonu uzerine isil islemin etkisi Ozet:  Bu calismada, Turkiye’de dogal olarak yetisen disbudak ( Fraxinus angustifolia  Vahl.) odununun boyutsal stabilizasyonu uzerine isil islemin etkisi arastirilmistir. Disbudak orneklerine su buhari ortaminda, farkli sicaklik (120, 160, 190 ve 210 °C) ve surelerde (3, 6 ve 9 saat) isil islem uygulanmistir. Deney ornekleri uzerinde, su alma orani (SAO), su itici etkinlik (SIE), genislemeyi onleyici etkinlik (GET) ve ATR-FTIR analizleri gerceklestirilmistir. Genel olarak isil islem sicaklik ve suresinin artisi ile SAO’larinda azalmalar meydana gelir iken, SIE ve GET degerlerinde artislar tespit edilmistir. Isil islem sicakliginin artisina bagli olarak, -OH gerilme titresimine ait piklerin absorbans degerlerinde azalmalar tespit edilmistir. Ozellikle 190 °C’de 3 saatlik uygulamada GET degerleri hizli bir artis ile %40’in uzerine cikmistir. Disbudak odununun en yuksek boyutsal stabilite degerleri (%58.4), en yuksek isil islem sicaklik ve suresinde (210 °C ve 9 saat) elde edilmistir. Sonuc olarak, isil islem uygulamasi ile disbudaktan uretilen masif odun urunlerinin kalite ve degerlerinin zehirleyici kimyasallar kullanilmadan artirilabilecegi gorulmustur. Anahtar Kelimeler:  Disbudak odunu ( Fraxinus angustifolia  Vahl.), boyutsal stabilizasyon, ATR-FTIR, su alma orani, su itici etkinlik Received (Gelis):  13.05.2016 -  Revised (Duzeltme):  06.06.2016 - Accepted (Kabul):  10.06.2016 Cite (Atif):  Sahin, H.I., Guler, C., 2017. The effect of heat treatment on the dimensional stability of ash ( Fraxinus angustifolia  Vahl.) wood.  Journal of the Faculty of Forestry Istanbul University  67(2): xxx-xxx. DOI: 10.17099/jffiu.xxxxx