Study On The Effect Of Mechanical Properties Of Wood-plastic Composite Materials After Environmental Temperature Effects

During the use of wood-plastic composites, they will be subject to the combined action of the external loading and environmental factors, which the representation of the mechanical properties is the deformation and fracture. The mechanical properties of wood-plastic composites are restricted to two sides, that is, both the properties of thermoplastic matrix resin and plant fiber fillers, in which the performance of thermoplastic matrix resin is the major influence factors. The relationship between the mechanical properties of polymers and both temperature and timeofoperation is significant. So temperature and timeofoperation are important parameters to study the mechanical properties of wood-plastic composites. And it is of great significance that the effect of temperature on the mechanical properties of wood-plastic composite is studied.The paper mainly focuses on HDPE-based wood flour/rice hulk composites which were treated in different temperatures'environments.Four aspects are included in this paper,the first interst is the change of bending properties of two kinds of wood-plastic composites, including HDPE+ wood flour and HDPE+ rice husk, after different temperatures'disposal; another focus of this study is the change of bending properties of two kinds of wood-plastic composites after different temperatures'balanced disposal; the third aspect is the effect the disposal of the temperature conditions on the bending properties of two kinds of wood-plastic composites; and the last content is the effect of the disposal of the temperature conditions on the creep behavior of two kinds of wood-plastic composites.According to the tests, the conclusions are drawn as follows:(1) The mechanical properties of wood-plastic composites are decreasing as the increase of temperature when they are subjected to different temperatures. When the treatment temperature is between -30℃and 50℃, the bending strength, elastic modulus, as well as the proportion of strain energy in the elastic region of HDPE-based wood flour composites and HDPE-based rice husk composites is dropping significantly. Such as when the treatment temperature is between -30℃and 50℃, the temperature rise every 10℃, and then the bending strength of HDPE-based wood flour/rice hulk composites separatly reduce about 3.15MPa,2.65MPa.(2) After different temperatures'balanced disposal, the mechanical properties come up obvious recovery. The parameters of flexural performance, bending strength, as well as the proportion of strain energy in the elastic region of HDPE-based wood flour composites and HDPE-based rice husk composites is decreased as the treatment temperature increased, but the range is less. Such as when the treatment temperature is between -30℃and 50℃, the temperature rise every 10℃, and then the bending strength of HDPE-based wood flour/rice hulk composites separately reduce about 0.87MPa,0.8MPa.(3) Because of different structural characteristics of flour and rice husk, both the compactness and the creep stability of HDPE-based rice husk composites is more than HDPE-based wood flour composites'. So the effect of temperature on the mechanical properties of HDPE-based wood flour composites is greater.