The bending and tension strength of furniture joints bonded with polyvinyl acetate nanocomposites

Furniture is the general name given for the portable equipment used in various human activities such as seating, working and relaxing. They can be a product of design and is considered a form of decorative art. They can widely be manufactured with different adhesives. Biodegradable and biobased adhesives which have no toxic compounds and non-dangerous elements have been selected since the furniture is generally benefited in interior locations. Meanwhile, polyvinyl acetate (PVAc) is a thermoplastic polymer which is widely used in the furniture industry. In this study, tension and bending strength of the furniture joints bonded with polyvinyl acetate adhesives filled with nano-TiO2 and nano-SiO2 were investigated. Three materials; oak (Quercus robur) wood, beech (Fagus orientalis) wood and plywood made with beech veneers were selected, and the joints were prepared by mortise and tenon joints. The results showed that the maximum value for the tension strength and bending strength were obtained to beech wood and oak wood in 2% addition of nano-SiO2 fillers. The minimum values for the tension and bending strength nano-SiO2 were found to plywood and 4% loading

Effects of Different Advanced Engineering Materials on Deformation Behaviour of Wood Structural Materials

Wooden composites reinforced with advanced engineering materials are promising as building materials. The use of these materials has been increasing in recent years. It is important to understand the behaviour of their deformation under load for optimum design of composite materials. There is limited information about the deformation behaviour of wooden composites under different loads. In this study, strain and displacement distributions were measured for wood structural materials made with glass fibre, carbon fibre, oak (Quercus robur), and polyurethane resin. The digital image correlation method (DIC) was used for this purpose. Deformation behaviours were determined from the images recorded under specific loads in the bending test. There was an increase of 17.3\% in bending strength of wood composites with the addition of glass fiber. The cracking process was visualized for different advanced engineering materials. The imagery clearly showed the development of the strain and displacement field. The deformation behaviours of reinforced and unreinforced wood composites were different. The strain distribution of wood composites significantly affected the strength properties

The quality comparison of particleboards produced from heartwood and sapwood of european larch

In this paper, the impacts of heartwood and sapwood usage on the physical, mechanical, and surface properties and formaldehyde emission of particleboard are investigated. European Larch (Larix decidua) trees are chosen as a raw material. The logs are divided into three segments: sapwood, heartwood and total wood. The highest amounts of cellulose (51.54%), and hemicelluloses (22.24%) in the sapwood, followed by total wood, and the heartwood, respectively. However, the highest amount of lignin (30.54%) was found in the heartwood. The highest extractives values are obtained from heartwood, followed by total wood, and the sapwood, respectively. While the lowest pH value (3.03) is found in heartwood, the sapwood samples provide the highest values (4.95). The highest ash (0.49%) content and amount of condensed tannin (13.89%) are extracted from heartwood, followed by total wood, and sapwood, respectively. The test panels manufactured from sapwood have the smoothest surface (7.49 µm (Ra), 48.86 µm (Ry), and 35.12 µm (Rz)) and the lowest contact angles (67.8ᵒ), while the roughest surface (14.20 µm (Ra), 68.05 µm (Ry), and 50.02 µm (Rz)) and highest contact angle (96.9ᵒ) are obtained from the panels of heartwood. The thickness swelling (19.88%) and formaldehyde emission (7.28%) values of the panels manufactured from heartwood are significantly lower than the panels manufactured from the total wood and sapwood. The highest modulus of rupture (MOR), modulus of elasticity (MOE), and internal bond (IB) values are observed on sapwood, respectively, 15.60 MPa (MOR), 2201 MPa (MOE), and 0.523 MPa (IB). These mechanical strength values (MOR, MOE, and IB) are followed by total wood, and the heartwood, respectively. Surface smoothness and wettability of the particleboards manufactured from sapwood are better than those of total wood and heartwood

Prediction of Wood Density by Using Red-Green-Blue (RGB) Color and Fuzzy Logic Techniques

Density is an important wood property since it correlates to mechanical properties of wood. Fuzzy logic, among the various available Artificial Intelligence techniques, emerges as a good technique in predicting. Digital image analysis is an powerful tool to obtain meaningful data out of an image. In this study, digital image processing based on a red-green-blue (RGB) color examination was practiced to measure the intensity of wood color. Densities of the test samples were measured. Then, a new fuzzy logic model was developed based on these measured values and RGB color intensity of wood. Afterwards, the experimental and modeling data results were compared. 98.17\% accuracy was observed between the measurement and the fuzzy logic model. Consequently, Fuzzy logic is visable method for the prediction of the wood density