Study On Wood Flour/HDPE Foaming Composites

Wood-plastics composites are a kind of new material, which are formed by wood, wood fiber(including wood flour, straw, shell of paddy) or other lignocellulose fibers with various plastics in different combining paths. With the integrating performance characteristic of wood and plastics, the new material will be utilized in very extensive field.In this paper, the optimum contents of the additives in HDPE/wood flour composite was investigated. Based on the fore-going formulation, the relationship between the composition, the structure and properties of HDPE/wood flour composite foams was studied systematically. Depending on the SEM micrographs, to observe the microcosmic configuration and structure of foam. In addition, the pilot study on the craftwork parameter such as rev of screw and temperature of machine foreside how to affect property of foam.The main works and conclusions were listed as following:1. HDPE /wood flour composite was prepared from HDPE and wood flour, the effects of the content of the wood flour, the effects of the type and content of surface treatment agent on the properties of WPC were studied. The results showed that the overall property of the composite was the optimum when the content of the wood flour was 100-150 phr, and the best content of the coupling agent was 5 % of the mass weight of the wood flour.2. Reserching the effects on the Mechanical Properties Of Wood-Plastics-Composite resulted by four different kind compatibilizers EVA, EAA,MA-PP,MA-PE. According to the Mechanical Properties and microcosmic physiognomy's testing result, it can be concluded that, firstly, rigidity of composite-materials has been increased, but tenacity fallen because of wood-powder being added; secondly, the Mechanical Properties of composite-materials with the addition of the Silane coupling agent are preferable; finally, MA-PP gave the best combined properties. Moreover, compared the effect of improving tenacity brought by two common used elastomers EPDM and SBS. The results showed that tenacity of composite materials has been improved after mixing inte elastomers and EPDM better than SBS.3. Foaming composite materials by adopting foaming method by used mould. After DSC analysis discovered that the use of chemical foaming agent(CFA) could decrease the specific weight of the composite effectively and improve the impact of the composite material. As to the blowing effect, the endothermic-exothermic balanced CFA was better than exothermic CFA. In addition, depending on comparing composite material and some common used wood, it is showed that in holding nail and static tension foaming-composite material is almost as well as some common used wood.4. Studied the extruding course of foaming-composite material, and then discussed the craftwork parameter how to affect the mechanical properties of foaming-composite-materials. The results showed that rev of screw should be set about 12 rpm and temperature of machine foreside controlled in the range near melting point of HDPE in that can make the mechanical properties of composite-materials best.