The Effect of Nano-Wollastonite on Physical and Mechanical Properties of Wood Plastic Composites Made With Sunflower Stem Waste and Alder

The effects of nano-wollastonite on physical and mechanical properties of wood plastic composites made with dried sunflower stalks and alder wood flour, were studied. Five levels of sunflower stalk flour in ratio of the mass wood dry flour containing 0, 25, 50, 75 and 100 percent and nano-wollastonite Powder in three levels, 3, and 5% were considered as variables of the study. Physical and mechanical properties, perpendicular to the screw strength, bending strength, modulus of elasticity, water absorption and thickness swelling after 2 and 24 soaking hours in water were measured in accordance with the standard DIN- EN. In order to examine the intersection of wood and polymer as well as distribution patterns of nanoparticles in the polymer matrix microscopic photos were taken. The results showed that by increasing of sunflower stalk flour in the mixing with wood flour up to 25% increased resistance to screw withdrawal and up to 50 percent increase in flexural strength and modulus of elasticity of wood-plastic composites, respectively. Sunflower stalk flour mixed with alder wood flour increased water absorption and thickness swelling after 2 and 24 hours immersion in water. The use of nano-wollastonite up 5% in relation to the total mass of all the boards improved the physical and mechanical properties of wood-polymer composite.