Study On The Interaction Mechanism Of Wood-plastic Composites

Wood plastic composite material is a new type of composite made of wood fiber and thermoplastic resin matrix,lubricants and interfacial modifiers as necessary auxiliaries,through mechanical mixing,melting and dispersing,forming and processing.Wood powder coated with epoxy resin coated wood powder and high density polyethylene,typical wood plastic composite lubricant and interfacial modifier are mixed to prepare wood plastic composite(wood powder filling amount is 60%).The effect of epoxy resin coated wood powder on the interaction of wood plastic additives is systematically studied.The effects of different auxiliaries on the interaction of components in low filling system were further studied by dynamic rheology.The main findings are as follows:(1)The analysis results of soluble substance content,thermal weight loss and surface micromorphology show that the one step addition method can improve the coating effect at low epoxy resin dosage and avoid the dispersion effect.The epoxy resin treatment of 6-8% can make the surface structure and state of wood flour achieve a basic steady state.(2)Study on the interaction of high filled composite system: the effects of epoxy resin coated wood powder on the interaction of system components were compared with the experimental methods of mechanical properties,rotational rheology,extrusion technology and water absorption under the condition of high filled wood plastic composite.The results show that the filling coating of epoxy resin on the surface of wood powder can inhibit the synergistic effect of PE wax / wax lubricants on MAPE or the negative effect of TPW604 lubricants,which shows the important role of porous structure of wood materials in the reinforced modification of wood plastic composites.(3)Study on the interaction of low filled composite systems: the effect of PE wax /paraffin lubricants and TPW604 lubricants on the WPC interface is also affected byepoxy resin under low filling system.It can be considered that the interface enhancement of WPC has a great correlation with the surface roughness and pore structure of the wood powder.30% the composite melt of wood powder content has the best interfacial properties,which further illustrates the existence and importance of interface interlocking mechanism due to the irregularity and roughness of wood powder.Different lubricants blocked the porous structure of wood flour and reduced the enhancement effect of MAPE on the interface,thus confirming the significance of porous structure to interface enhancement.