Research On Preparation And Property Of The Long Bast Fiber Reinforced High Density Polyethylene Composite

The preparation of natural plant fiber reinforced thermoplastic was usually divided into two steps:granulation by twin screw extruder or mixer and molding by single screw extruder or injection machine, which resulted in that the natural fiber length in composite materials was not enough, seriously affecting the effects of reinforcement. In this paper, long jute fiber reinforced high density polyethylene (HDPE) composites was made by melt impregnation process. The natural fiber can reinforce thermoplastics effectively, due to avoid mixing shearing action of granulation by twin screw extruder or mixer. The following is the detail:1. According to the specificity of nature fiber, a device for thermoplastic melt impregnation of nature fiber was developed at our laboratory. Long jute fiber reinforced high density polyethylene was prepared by this equipment. The influence of preparation technology and forming processes on the properties of composites was studied2. The effect of fiber content, impregnation temperature, compatilizer malefic anhydride grafted polyethylene (MAPE) content and pellets length on the mechanical properties and microstructure of composites was studied. The optimization of preparation technology was determined.3. By designing orthogonal tests, the influence of screw speed, barrel temperature and injection rate on mechanical properties and microstructure of long jute/HDPE composites were studied, and optimized preparation technology of injection molding process was determined.4. Four kinds of compound board were made by extrusion molding, injection molding, compression molding and injection pressing molding. Through analysis and comparison, the optimization of forming process was studied.The periodic achievements of this paper can provide technology support for industrialization of long nature fiber reinforced thermoplastic composites.