Water absorption and mechanical properties of scots pine (Pinus sylvestris L.) wood samples treated with alkyl ketene dimer / boric acid combinations

Abstract

In order to build resistance against liquids, alkyl ketene dimer (AKD) is mostly employed in paper industry because it modified some properties of the paper such as wet strength and printability. AKD gets into a reaction with wood hydroxyl groups and the subsequent orientation of hydrocarbon chains effectively contributes to esterification. Thus, the dimensional stability of wood is improved with AKD addition. Additionally, boron compounds are quite useful in wood protection as environmentally friendly chemicals and they are effective as insecticides and fungicides. On the other hand, they have negative sides such as higher water solubility and leaching. These can be prevented by combining boron compounds with AKD. In this study, Scots pine (Pinus sylvestris L.) wood samples were impregnated with AKD (5%, 10%, 18%) and boric acid (3% BA) combinations. AWPA E4 standards were used for water absorption and dimensional stability test, and TS 2471 standards were used for compression strength parallel to the grain of the wood. The results indicated that AKD/BA combination had lower water absorption. In the mechanical test, the mechanical properties of the samples improved somewhat with the synergistic effect of AKD and BA.

Keywords

• Alkyl ketene dimer
• mechanical properties
• dimensional stability

Alkil keten dimer / borik asit kombinasyonları ile emprenye edilen sarıçam (Pinus sylvestris L.) örneklerinin boyutsal kararlılığı ve mekanik özellikleri

Abstract

Alkil Keten Dimer (AKD); ıslak mukavemet ve kâğıdın basılabilirlik özelliklerini değiştirdiği için çoğunlukla kağıt endüstrisinde kullanılır. AKD, odunun hidroksil gruplarıyla reaksiyona girer ve hidrokarbon zincirlerinin etkili bir şekilde esterleşmesine katkıda bulunur. Oduna AKD ilavesi ile boyutsal kararlılığın arttırılması hedeflenmiştir. Ayrıca çevre dostu olan bor bileşikleri ahşabın biyolojik zararlılara karşı korunmasında oldukça etkilidir. Ancak bor bileşikleri odundan kolayca yıkanabilmektedir. AKD/BA sinerjik etkisi ile birlikte bu olumsuz özelik giderilmeye çalışılıp odunun boyutsal kararlılığı arttırılmaya çalışılmıştır. Bu çalışmada AKD (%5, %10, %18) ve borik asit (%3 BA) kombinasyonları ile emprenye edilmiş sarıçam (Pinus sylvestris L.) odun örnekleri kullanılmıştır. Örneklerin su alma ve boyutsal kararlılıkları ile mekanik özellikleri belirlenmiştir. Su alma ve boyutsal kararlılık testi için AWPA E4, liflere paralel basınç direnci için TS 2471 standartları kullanılmıştır. Elde edilen sonuçlara göre AKD/BA kombinasyonunun daha düşük su alma oranına sahip olduğu görülmüştür. Mekanik testte AKD ve BA sinerjik etkisi ile birlikte örneklerin mekanik özellikleri bir miktar iyileşmiştir.

Keywords

• alkil keten dimer
• mekanik özellikler
• boyutsal kararlılık

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