CHEMICAL MODIFICATION OF PAULOWNIA, POPLAR, AND EUCALYPTUS WOOD BY ε-CAPROLACTONE GRAFTING INSIDE CELL WALLS TO IMPROVE WOOD PROPERTIES

Abstract

Wood is an excellent engineering material with its light weight and high mechanical properties, and has been used for furniture production from the early ages of humankind. However, its susceptibility to biodegradation due to its hygroscopic nature and chemical composition limits usage of wood as outdoor furniture. For the outdoor utilization, chemical modification methods may provide long service-life to the products. Water repellence and dimensional stability can be both improved up to 70% and 40% respectively by inserting hydrophobic molecules inside spruce wood cell walls. Paulownia, Poplar, and Eucalyptus are fast growing trees and their wood has different properties. In this study, a pretty new modification method was carried out by grafting a hydrophobic polymer poly(ε-caprolactone) (PCL) onto economically valuable Paulownia, Poplar, and Eucalyptus wood cell walls. The water absorption, dimensional stability (ASE), equilibrium moisture content (EMC), and density change of poly(ε-caprolactone) grafted wood were characterized and found that dimensional stability and water repellence has significantly better compared to references for poplar wood but not for the paulownia and eucalptus. 

Keywords

• poli(ε-caprolacton)
• wood
• chemical modification
• dimensional stability

PAVLONYA, KAVAK VE ÖKALİPTUS AHŞABININ ÖZELLİKLERİNİN İYİLEŞTİRİLMESİ İÇİN ԐKAPROLAKTON İLE KİMYASAL MODİFİKASYONU

Öz

Ahşap düşük özgül ağırlığına karşın yüksek direnç özelliklerine sahip olması nedeniyle mükemmel bir mühendislik malzemesidir ve insanlığın erken çağlarından bu yana mobilya üretiminde kullanılmaktadır. Bununla birlikte, biyolojik bozunmaya duyarlılığı, higroskopik yapısı ve kimyasal bileşiminden dolayı dış ortam mobilyalarında kullanımı kısıtlıdır. Dış mekanda kullanım için kimyasal modifikasyon metotları ürünlere uzun servis ömrü sağlayabilir. Ladin odun hücre duvarlarına hidrofobik moleküller yerleştirerek su iticiliği ve boyutsal kararlılığı sırasıyla %70 ve %40 oranında arttırılabilir. Pavlonya, Kavak ve Ökaliptus hızlı büyüyen ağaçlardır ve ahşapları farklı özelliklere sahiptir. Bu çalışmada ekonomik olarak değeri olan Pavlonya, Kavak ve Ökaliptus ahşap hücre çeperlerine hidrofobik bir polimer olan poli(ε-kaprolakton) (PCL) aşılanmasıyla çok yeni bir modifikasyon yöntemi uygulanmıştır Poli (ε-kaprolakton) aşılanmış farklı ahşap türlerinin su emme, boyutsal kararlılığı (ASE), denge rutubet miktarı (DRM) ve yoğunluk değişimi karakterize edildi. Kavak ahşabının özelliklerinin yüksek oranda iyileşmiş ancak pavlonya ve okaliptüste iyileşme görülmemiştir.

 

Anahtar Kelimeler

• poli(ε-kaprolakton)
• ahşap
• kimyasal modifikasyon
• boyutsal stabilite

Kaynakça

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