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In this study, effect of nano-wollastonite on fire resistance characteristics of wood flour/polypropylene composite was investigated. The composites samples were manufactured using a dry blend/hot press method. In this study, the dried wood flour of beech as the filler in a 60%, poly propylene as the matrix in a 37% and polyethylene grafted with maleic anhydride as the coupling agent in a 3% total weight was used. Also, nano-wollastonite was used in four levels of dried wood flour loading (0, 1, 3 and 5%). Nominal density and dimensions of the composites were 1 g/cm3 and 1*20*25 cm, respectively.Bending strenght according to ASTM standard and Fire resistance characteristics such as, flammability duration, duration of flame after removing the burner, duration of glow after removing the burner and mass reduction were measured acceding to ISO 11925. Results indicated that by increasing the nano-wollastonite increases the bending strengh,MOE and flammability duration increased but mass reduction, duration of flame and duration of glow decreased. Also the dispersion of nano-wollastonite in composites was evaluated by Filed Emission Scanning Electron Microscopy (FE-SEM).

In this study the effect of white and brown-rot fungi on durability and hardness characteristics of Bagasse/Polypropylene composite was evaluated. The test specimens were prepared using Bagasse fibers (38%), Polypropylene (60%), and maleic anhydride (2%) according to respective standard and by hot press method. Then specimens were exposed to white (Coriolus versicolor) and brown-rot (Coniophora puteana) fungi according to BS 838:1961 standard and Kollescale method at 8, 12 and 16 weeks. After that, superficial damage, weight loss, and hardness strength of samples were determined. The results showed that superficial damage of brown-rot fungus was lower than white-rot fungus. The weight loss of white-rotted samples were significantly (P

In study, the influence of flour content and immersion time in water on the creep behavior of composites made from mixes PB (Particle Board) and MDF (Medium Density Fiber Board) flour and high density polyethylene (HDPE) waste and was investigated. Mixing was done by a twin screw extruder and the sample was manufactured by flat hot press. Firstly, the modulus of elasticity and bending strength of various mixes PB and MDF flour-polyethylene composites (WPCS) were measured before performing the creep test.It was shown that the modulus of WPCs increases with the increase in mixes PB and MDF flour content from 60% to 70% and then decreases as the flour content reaches to 80%. It is found that the bending strengths of WPCs significantly and linearly decreases with the increase in flour content from 60% to 80%. The results showed that, the creep strain decreases as the lignocellulosic flour level increases. Water absorption has negative effect on creep behavior of mixes PB and MDF flour/HDPE composites. For all filler contents, it can be seen that the creep strain increases when the immersion time increases.

The possibility of producing wood-plastic panels using two methods including melt blend and dry blend was studied in this research. Methods were compared with each other in order to select the best. Wood-Plastic panels were made from high density polyethylene (as resin) and particle board waste (as natural fiber) at 60, 70 and 80% by weight fiber loading. Density and dimensions of the panels were lg/cm3 and 35*35*1 cm, respectively. Mechanical properties of the panels including flexural modulus, flexural strength, screw and nail withdrawal resistance, and impact strength were under investigation. Maximum values of flexural modulus of wood plastic panels were found at 70% fiber content in both methods. Flexural strength, screw and nail withdrawal resistance and impact strength of wood plastic composites reduced with the increase in fiber content from this is not a reduction 60% to 80% is increase. Mechanical properties of samples made with dry blend method were generally higher than those of samples made with melt blend method for an corresponding formulations.

The possibility of producing wood-plastic panels using melt blend method was studied in this research and mechanical properties of the panels including flexural modulus, flexural strength, screw and nail withdrawal resistance, and impact strength were studied.Wood -Plastic panels were made from high density polyethylene (as resin) and MDF waste and particleboard waste (as natural fiber) at 60, 70 and 80% by weight fiber loading. Density and dimensions of the panels were 1g/cm3and 35*35*1 cm, respectively. Results indicated that the mechanical properties of the composites are strongly affected by the proportion of the wood flour and polymer in the material. Maximum values of flexural modulus of wood plastic panels were found at 70% fiber content in both methods. Flexural strength, screw and nail withdrawal resistance and impact strength of wood plastic composites reduced with the increase in fiber content from 60% to 80%.