Wood-plastic Composites Preparation And Properties Of Foam Materials Research

Wood-plastic composites (WPCs) are made from thermoplastic polymer mixed with sawdust or wood flour, plant fiber powder and a variety of processing aids. After a high-temperature mixing, extrusion, molding, injection molding, a kinds of environmentally friendly composite materials can be obtained. Because the material is low cost, WPCs can be widely used in construction, transportation, light industry and have broad market prospects and environmental value. But the Wood-plastic composites have some shortcomings. The density of WPCs is usually twice of wood. As a result of the addition of wood flours, negative effects on ductility and impact strength of the WPCs are observed. The objective of this study is to investigate and produce the foamed wood-plastic composites in the following aspects.(1)Obtained the formula by compared with the WPC made from PP and PE. The effects of wood flour content, compatibilizer content and coupling agent content on the mechanical properties of WPCs are observed. At last we have the optimum ratio of wood flour / MAPP of 60%:8%.(2)Selected the appropriate foam in the optimum ratio of the WPCs. The effects of the foaming agent content, wood flour content on the mechanical properties of the WPCs made from PP and PE are investigated. The results showed that the density of foaming wood-plastic composites have a significant decrease and impact strength is improved. However, tensile and bending strength decreased with increasing the foaming agent content. when foaming agent dosage is 1.5%, the density of the WPCs made from PP reduced by 17%, impact strength is 23.3kJ/m2. And the density of the WPCs made from PE reduce the density of by 18.8%, the impact strength increased by 23%. The WPCs made from PP should be used foaming agent TA-210, and the best dosage is 1.5%. The WPCs made from PE should be used foaming agent TA-600, and the best dosage is 1%. The density of the WPCs has a slightly increase with the addition of wood flours, while the mechanical properties of materials is decreased. But the cost of materials can be reduced significantly ,so we can add a appropriate amount of wood flour.(3)Compared the WPCs using homemade foaming agent and foaming agent, processing conditions on the foaming properties of the material . Observed the foam pore structure by electron microscopy. The results showed that the properties of foam WPCs is better than the WPCs did not foam. The amount of foaming agent is determined the amount of bubble. In our study, the experiment is micro-foam. The more the foaming agent used, the more the mechanical properties decreased. The amount of blowing agent of 0.5% is best. The addition of nucleating agents can increase the number of bubble , make bubble holes evenly distributed and pore size uniform performance, so the mechanical properties of the WPCs can be increased. If nucleating agents increase so much, it will become a filler. Then the mechanical properties will be decreased. In this paper, the amount of 8% is the best. The controlling factor is very important in the production of wood-plastic foam. According to the plastic, the best processing temperature of this experiment is 180℃. But in order to protect their non-feeding, let the sample cool down after the shot, then storage material. Observed by electron microscopy, foam structure of the WPCs using foaming agent is more uniform and the bubble hole diameter smaller than the WPCs without the foaming agent.(4)This paper study the properties of WPCs made from the recycled plastic, rice husk powder or bamboo powder that replace a new plastic and wood flour. The results showed that if the production conditions are not changed, using recycled materials instead of new materials is feasible. The mechanical properties of WPCs made from recycled plastic is lower than the new. But the difference is not obvious. However, recycled materials can reduce the waste plastics in the environmental and can also reduce production costs . The WPCs made from bamboo powder has the highest density and the bending strength. The WPCs made from rice husk powder has the best impact strength. This Show that the formula has a strong applicability and has a good guidance in the actual production.