Four kinds of iron oxide pigments were added into wood-fiber/high-density-polyethylene composites （WF/HDPE） at three different concentrations, to determine the effects of pigments on the changes in the color and mec...Four kinds of iron oxide pigments were added into wood-fiber/high-density-polyethylene composites （WF/HDPE） at three different concentrations, to determine the effects of pigments on the changes in the color and mechanical properties of the composites before and after UV accelerated weathering. HDPE, wood fibers, pigments and other processing additives were dry-mixed in a high-speed mixer. The mixtures were extruded by two-step extrusion process with a self-designed twin-screw/single-screw extruder system. Color of the samples was determined according to CIE 1976 L^＊a^＊b^＊ system by a spec- trophotometer and the bending properties were tested to evaluate the mechanical properties before and after accelerated UV weathering. The result shows that the modulus of elasticity of WF/HDPE did not obvi- ously changed after incorporating with the pigments, but the bending strength increased. After accelerated aging for 2000 h, both color and mechanical properties significantly changed. Iron oxide red and black performed better than the other two pigments, and the pigments dosage of 2.28% in the composites is favourable.展开更多
In recent years,natural fiber reinforced composites have been widely applied to various industrial products for their excellent environmental-friendly performance.It is essential to understand the mechanical propertie...In recent years,natural fiber reinforced composites have been widely applied to various industrial products for their excellent environmental-friendly performance.It is essential to understand the mechanical properties of natural fiber reinforced composites under their in-service environment.Compared with synthetic fibers,the hydrophilicity of natural fibers could result in a much larger quantity of water absorption from the moisture atmosphere,which would have adverse consequences for the durability of natural fiber reinforced composites[1].The environmental temperature would affect the展开更多
基金supported by the National Natural Science Foundation of China (30671644, 30771680)
文摘Four kinds of iron oxide pigments were added into wood-fiber/high-density-polyethylene composites （WF/HDPE） at three different concentrations, to determine the effects of pigments on the changes in the color and mechanical properties of the composites before and after UV accelerated weathering. HDPE, wood fibers, pigments and other processing additives were dry-mixed in a high-speed mixer. The mixtures were extruded by two-step extrusion process with a self-designed twin-screw/single-screw extruder system. Color of the samples was determined according to CIE 1976 L^＊a^＊b^＊ system by a spec- trophotometer and the bending properties were tested to evaluate the mechanical properties before and after accelerated UV weathering. The result shows that the modulus of elasticity of WF/HDPE did not obvi- ously changed after incorporating with the pigments, but the bending strength increased. After accelerated aging for 2000 h, both color and mechanical properties significantly changed. Iron oxide red and black performed better than the other two pigments, and the pigments dosage of 2.28% in the composites is favourable.
基金supported by the Shenzhen Municipal Government through the Fundamental Research Project(Grant No.JCYJ20170307151049286)the National Natural Science Foundation of China(Grant No.11572227)
文摘In recent years,natural fiber reinforced composites have been widely applied to various industrial products for their excellent environmental-friendly performance.It is essential to understand the mechanical properties of natural fiber reinforced composites under their in-service environment.Compared with synthetic fibers,the hydrophilicity of natural fibers could result in a much larger quantity of water absorption from the moisture atmosphere,which would have adverse consequences for the durability of natural fiber reinforced composites[1].The environmental temperature would affect the
