Influence of paper mill sludge on the long term hygroscopic behavior of flat pressed wood-plastic composites

Lignocellulosic material used as raw material in pulp and paper production due to major chemical alterations produce different waste compounds and composite manufacturing is an area providing the opportunity to utilize such wastes. In order to investigate the feasibility of using papermaking sludge in composite production, four combinations of wood flour/ papermaking sludge/ high density polyethylene ratio were formulated, then composite panels  were made and the physical properties of manufactured panels were evaluated. The content of maleated polyethylene (MAPE) and the polymer was constant 2% and 38% respectively, for all formulations. The results indicated that long term water absorption in particular thickness swelling decreased with increasing sludge content. Furthermore, moisture diffusion coefficient of samples containing 30% sludge and 30% wood flour was more than others. The results revealed that using papermaking sludge can be an alternative option for lignocellulosic raw material

Study on the effect of urea addition to urea-formaldehyde adhesive on physical and mechanical properties of poplar particleboard

In this research, the effect of increasing content of urea to urea-formaldehyde adhesive on physical and mechanical properties of  poplar wood particleboard was investigated. The content of urea added to the adhesive four levels (zero, 4.1, 8.2 and 16 % based on the solid content of adhesive) and two press temperatures of 170 and 180° C as the variable factors were selected. Boards with density of 0.63 gr/cm3 and 10% of the adhesive dosage were made. Mechanical properties including modulus of rupture (MOR), internal bond (IB) and physical properties including water absorption and thickness swelling were measured. Results showed that urea addition to urea formaldehyde adhesive improved the mechanical strengths of the board especially internal bonding reduced the water absorption and thickness swelling. Also, the impact of press temperature on mechanical and physical properties of boards was noticeable and boards produced applying press temperature of 170° C were superior

Utilization of date palm and kenaf fibers for reinforcement of practical properties of plywood

Utilization of date palm and kenaf fibers for reinforcement of plywood was investigated and after making plywood with layers of horn beam wood (Carpinus betulus), physical and mechanical properties were analyzed. Variables were the type of fiber (kenaf and date palm), the type of filler (wheat flour and waste paper) and the content of resin (150 and 200 g/m2). The results of this study show that utilization of kenaf and date palm fibers was effective in improvement of physical and mechanical properties of plywood. The mean of specific gravity for reinforced plywood with kenaf and date palm fibers was 0.723 and 0.739 g/cm3 respectively and specific gravity of control was 0.656 g/cm3. The least water absorption and thickness swelling were about reinforced boards with kenaf fibers and 200 g/m2 resin with wheat flour filler .The reinforced boards with kenaf fibers and 150g/m2 resin with wheat flour filler have the best mechanical properties. So the kenaf fibers for reinforcement of properties of plywood were better than date palm fibers and the utilization of wheat flour in manufacture of these boards had better results compared to waste paper filler

Effect of mat moisture content and Cu nanoparticles on heat transfer and physical and mechanical properties of poplar particleboard

Effects of mat moisture content (MC) and Cu nanoparticles on heat transfer and physical and mechanical properties of poplar particleboard were investigated. Three levels of mat moisture content (9, 12 and 15%. based on oven dried wood particles) and two levels of Cu nanoparticles (0 and 15% based on oven dried resin) were selected as variable factors. Results indicated that mechanical properties of particleboard improved as MC increases. Cu nanoparticles accelerated the heat transfer from the surface layer to the core layer of the mat and subsequently increased the internal bonding. This positive effect was evident as MC increased. Water absorption and thickness swelling increased as either MC or Cu nanoparticles content was raised. It was observed that the efficiency of Cu nanoparticles on heat transfer was superior at higher MC. Energy Dispersive X-Ray Spectroscopy (EDS) and Scanning Electron Microscopy (SEM) determination revealed that the presence and very well dispersion of Cu nanoparticles in glue line

Evaluation of steam pretreatment of poplar wood particles on the mechanical and physical properties of particleboard

In this research the effect of steam pretreatment on the physical and mechanical properties of particleboard were evaluated. Steam pre-treatment was applied on the particles of poplar wood in a stainless steel reactor at four different temperature (155, 165, 175 and 185 ◦C) and three different retention time (15, 30 and 45 min). The obtained results indicated that mechanical properties include MOR and IB content of the particleboard decreased, whereas MOE increased initially then decreased with severity of treatment conditions. The physical properties of the board i.e. thickness swelling, water absorption and consequently dimensional stability were improved by steam pretreatment. The observed changes can be attributed to reduction in hemicelluloses content and hydroxyl groups within wood component

Effect of filler material and foaming agent on practical properties of wood plastic composites

In this study, feasibility of foaming wood plastic composites using injection molding process was investigated. The effect of lignocellulosic raw material (Poplar saw dust and soybean straw flour) on the properties of composites was examined. Wood plastic composite boards with 3.2 mm thickness, 105 mm width and 105 mm length were prepared using high density polyethylene granules.  The foaming agent (Azodicarbonamide) at 2 wt % was also used. The scanning electron microscope micrographs confirmed that foaming process has been successfully carried out. The Results showed that all mechanical properties (except the impact strength) decreased while water absorption increased as the microcellular foaming method was used. Adding soybean straw flour to the foam structure led to​​ the decrease in flexural strength, flexural modulus of elasticity and tensile strength. Water absorption and thickness swelling were negatively affected with the addition of soybean straw flour

Investigation of OCC Fiber/Polymers Composites in Air – Forming Production

This study investigated the effects of production variables on physical and strength properties of air-formed OCC fibers / polymer composites. A combination of 12  treatments of OCC fibers and coupling agents for air-forming were investigated. Physical and mechanical properties of the sample were analyzed using factorial experimental design with completely randomized and DMRT test is used to classified the averages. The results of this study showed that addition of 70% OCC fibers to the polymers in air forming resulted in composites with higher strengths and modulus of rupture and 55% OCC fibers increased internal bonding, tensile strength and modulus, and lowered thickness swelling. Thickness swelling after 2 h water-soak and mechanical properties were improved by addition 2 and 4 % coupling agen