Composite wood products
Sina Khodaparast; Ahmad Jahan - Latibari; Mehran Rohnia
Abstract
The effect of compounding process applying two methods of one and two step mixing on the properties of nanocomposite is investigated. Nanocomposites were produced using polypropylene, cellulosic fibers, MAPP and nanolay as reinforcement. 1.5 and 3% MAPP and 0,2, and 4% nanoclay were used as the variable ...
Read More
The effect of compounding process applying two methods of one and two step mixing on the properties of nanocomposite is investigated. Nanocomposites were produced using polypropylene, cellulosic fibers, MAPP and nanolay as reinforcement. 1.5 and 3% MAPP and 0,2, and 4% nanoclay were used as the variable factor and 20% fibers was used. Melt flow index was measured on compounds produced using one or two steps mixing. Either compounds were mixed with fibers and MAPP and then the test specimens were made and tested according to ASTM test procedures. The results revealed that the two steps mixing increased the mechanical properties. The melt flow index of one step mixing was lower and the melt flow index of initial mixing of polypropylene with nanoclay was very high and it was reduced after compounding with fibers and MAPP. The results revealed that at higher dosages of the nanoclay tensile and bending modulus of the composite increased and tensile strength and modulus of rupture decreased.
Porya Rezaei niaraki; Ahmad Jahan Latibari; Azhang Tajadini; Mehran Roohnia
Abstract
The influence of fiber lignin content and the dosage of coupling agent on the strength and physical properties of cellulosic fiber-polypropylene composite were investigated. The old corrugated container (OCC) fibers were delignified using sodium hydroxide to reach the lignin content of 2.7, 3.78, 5.26 ...
Read More
The influence of fiber lignin content and the dosage of coupling agent on the strength and physical properties of cellulosic fiber-polypropylene composite were investigated. The old corrugated container (OCC) fibers were delignified using sodium hydroxide to reach the lignin content of 2.7, 3.78, 5.26 and 7%. Fibers were compounded with polypropylene by extrusion process using 20% fibers and 77% PP and the extrudate was cooled and grinded to fine granulates before injection molding. MAPP coupling agent was applied at three different levels (1, 2 and 3 percent based on the total weight of the composite). The strength properties of the composites were measured using relevant ASTM test methods and the results were statistically analyzed using factorial experiment under complete randomized design. The impact of fiber lignin content of flexural strength of composite was statistically significant at 98 percent significance level and the lowest and highest values of flexural strength of composite were measured at 3.78 percent and 7 percent lignin content of fiber. The interactive effect of fiber lignin and MAPP on the tensile strength and flexural modulus of elasticity of the composite showed that at lower values of lignin and higher dosage of MAPP, these properties are 38.7 and 3438 MPa respectively. Other strength values of the composites were also improved and at lower content of lignin and increaing dosages of the MAPP, the impact strength of the composites was increased from 52.82 J/m to 60.26 J/m.
Physics and anatomy
Alireza Ghotibi far; Saeid Kazemi najafi; Rabi Behroz
Abstract
This research focused on the influence of content (5, 10 and 15 %) of glass fiber on the water absorption and thickness swelling of wood flour/E-glass fiber hybrid polypropylene composites without and with MAPP. The samples (strips with 10 mm thickness and 70 mm width) were made using a laboratory twin-screw ...
Read More
This research focused on the influence of content (5, 10 and 15 %) of glass fiber on the water absorption and thickness swelling of wood flour/E-glass fiber hybrid polypropylene composites without and with MAPP. The samples (strips with 10 mm thickness and 70 mm width) were made using a laboratory twin-screw extruder. The water absorption and thickness swelling of the composites after 2h and 24h were determined. The results showed that adding glass fiber significantly increase water absorption and thickness swelling after 2h and 24h in absence of MAPP. Whereas in presence of 2% MAPP by addition glass fiber, no significant changes were observed in water absorption and thickness swelling of the composites after 2h and 24h. MAPP considerably decreased the water absorption and thickness swelling of the studied composites
Composite wood products
Ali akbar Enayati; Davood Rasooli; Hossein Usefi
Abstract
In this study, plywood manufacture with use of polypropylene as a binder has been studied. The variables were polypropylene in three levels of 80, 120 and 160 g/m2 and maleic anhydride polypropylene coupling agent in two levels of 0 and 4 g/m2 . ureformaldehyde and wheat flour were ...
Read More
In this study, plywood manufacture with use of polypropylene as a binder has been studied. The variables were polypropylene in three levels of 80, 120 and 160 g/m2 and maleic anhydride polypropylene coupling agent in two levels of 0 and 4 g/m2 . ureformaldehyde and wheat flour were used for control samples(120 and 40 g/m2 respectively). Physical and mechanical properties including MOR and MOE (parallel and perpendicular to grain of face layers), water absorption and thickness swelling after 2 and 24 hours of immersion in water were tested. The results showed that maleic anhydride polypropylene coupling agent has significant effect on MOR parallel to grain of face layers. With increase of maleic anhydride polypropylene coupling agent, MOR increased. Polypropylene has positive effect on thickness. With increase of maleic anhydride polypropylene coupling agent, water absorption after 24 hours improved. Although the results revealed improvement in board properties resulted from more polypropylene use but in all properties (except thickness swelling after 24 hours), control samples had better quality than plywood made from polypropylene.
Amir Nourbakhsh; Bohuslav V.Kokta; Abdolrahman Hosseinzadeh; Ahmad Jahan latibari; Abolfazl Kargarfard
Abstract
This study investigates the effect of maleic anhydride polypropylene (MAPP) addition as a coupling agent at four levels and also the type of cellulosic materials as a reinforcing component on processing and mechanical properties of modified Populus deltoides fiber and flour/ polypropylene composites.The ...
Read More
This study investigates the effect of maleic anhydride polypropylene (MAPP) addition as a coupling agent at four levels and also the type of cellulosic materials as a reinforcing component on processing and mechanical properties of modified Populus deltoides fiber and flour/ polypropylene composites.The results indicate that the interfacial bond between reinforcing-fiber/ flour and the matrix show great influence on the mechanical properties of composites. Furthermore it has been demonstrated that the addition of coupling agent during processing significantly improves the mechanical properties of fiber/ flour polypropylene composites. The results of this investigation indicates that the highest the mechanical properties of composites are as follow; The mechanical properties of the poplar fiber with 2% MAPP is higher than poplar flour without MAPP, which proves that the addition of functional group C=O acts as a good bonding agent. The notched Impact Izod strength value of poplar fiber with 2% MAPP is less than pure PP. But it is higher than other treatments. The results indicate that the interfacial bond between reinforcing fibers and flour with polymer matrix modified MAPP play a significant role in improving the measured mechanical properties of the composites.
