Effect of Alkaline Concentration on Mechanical Properties of Wood Flour Filled PVC Composites

Abstract

This study was carried out to determine the effect of modified wood flour on thermoplastic composites. For this purpose, wood flour treated with alkali (sodium hydroxide (NaOH)) at different concentrations (0-3-6-12%) were added to polyvinyl chloride (PVC) polymer to produce wood-PVC composites. In order to determine the effect of alkali treatment on the mechanical properties of wood-PVC composites, tensile strength, tensile modulus, flexural strength, flexural modulus and hardness values were determined. It was determined that the tensile strength, flexural strength and modulus of elasticity values of the composite samples containing alkali-treated wood flour were higher than those containing untreated wood flour. The highest tensile and flexural strength values were determined in the composite sample containing 6% NaOH treated wood flour. In addition, it was observed that the hardness values of the composite samples were not affected much by the alkali treatment. In addition, thermogravimetric analysis (TGA) results showed that alkali treatment caused an increase in the thermal stability of composite materials.

Keywords

• Alkali treatment
• mechanical properties
• wood flour
• polyvinyl chloride

Alkali Konsantrasyonunun Odun Unu Takviyeli PVC Kompozitlerin Mekanik Özelliklerine Etkisi

Öz

Bu çalışma, modifiye edilmiş odun ununun termoplastik kompozitler üzerindeki etkisini belirlemek amacıyla yapılmıştır. Bu amaçla, farklı konsantrasyonlarda (%0-3-6-12) alkali (sodyum hidroksit (NaOH)) ile muamele edilmiş odun unu, polivinil klorür (PVC) polimerine ilave edilerek odun-PVC kompozitleri üretilmiştir. Alkali muamelesinin odun-PVC kompozitlerin mekanik özelliklerine etkisini tespit etmek için çekme direnci, çekmede elastikiyet modülü, eğilme direnci, eğilmede elastikiyet modülü ve sertlik değerleri belirlenmiştir. Alkali ile muamele edilmiş odun unu içeren kompozit numunelerin çekme direnci, eğilme direnci ve elastikiyet modülü değerleri muamele edilmemiş odun unu içerenlerinkine kıyasla daha yüksek tespit edilmiştir. En yüksek çekme ve eğilme direnci değerleri %6 NaOH muameleli odun unu içeren kompozit numunesinde tespit edilmiştir. Ayrıca, kompozitlerin sertlik değerlerinin, alkali muamelesinden çok fazla etkilenmediği görülmüştür. Bunlara ek olarak, termogravimetrik analiz (TGA) sonuçları, alkali muamelesinin kompozit malzemelerin termal kararlılığında artışa sebep olduğunu göstermiştir..

Anahtar Kelimeler

• Alkali muamelesi
• odun unu
• polivinil klorür
• mekanik özellikler

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