The Research Of The Impact Of Mechanical Parameters On The Mechanical Properties Of WPCs

The key point to this research consists in the compounding process and improving the compatibility between wood fiber and thermoplastic polymer.In addition,optimize the bonding state of wood fiber and thermoplastic;develop the designable property of composite and improve the dimension stability of pure wood material.In this paper we used birch powder and HDPE as the main raw material to manufacture composite by the process of melting extrusion.Study the effect which caused by the change in temperature and rotational speed of the extruder as well as the coupling agent on the properties of composite materials.The use of analysis such as regression analysis,image processing, DMA and SEM to get the relationship between extruder speed as well as temperature and the mechanical properties of materials.1.Extrusion of birch powder-HDPE composite.A set of 30 twin screw and 45 single screw were used for extruding at 150-195℃temperature.Both bending strength and compact strength of extruded material were higher,which implied extrusion compounding technology is suitable for wood/plastic material manufacturing and the extruded material may replace wood products in certain application.The bending strength and modulus of elasticity of wood fiber composite containing MAPE coupling agent are obviously higher than that of composite without coupling agent.It will be facility to compound with plant fibers and coupling agent by ester or hydrogen bond at certain temperature.Therefore,graft copolymerization occurs between plastic polymer and plant fibers,and bonding strength improves.Strength of samples increased slightly with adding coupling agent.With an increasing proportion of the coupling agent,a slight increase in the strength of materials. 2.Change the temperature of three zones of twin-screw extruder and screw speed,testing the mechanical properties of composite materials,combine with image processing technology, discuss the relationship between raw materials mixed and temperature,speed,to explore the online testing of composite materials performance.3.SEM and DMA observation and analysis showed that the interface performance of the composite can be improved by adding the coupling agent,and it must be in the suitable proportion.