Preparation And Properties Of Flame Retardant And Antistatic Foamed Wood-plastic Composite

Foamed wood-plastic composites（FWPC）can reduce the cost of raw material use and meet the"reduction"requirements of the manufacturing industry.As the focus of future research,functional wood-plastics have practical significance for expanding the application of wood-plastic materials.In this paper,Salix and PE-HD wereused as raw materials to prepare FWPC by molding method.The effects of foaming process,wood-plastic interface modification process and functional modification additives on the performance of FWPC were studied,and light-weight,high-strength flame-retardant and antistatic FWPC was prepared,which provided theoretical basis and technical support for the performance optimization of wood-plastic materials.The main research contents and conclusions were as follows:（1）The effects of AC,Zn O and Nano-Ca CO₃ additions on the properties of FWPC were investigated.When the additions of AC,Zn O and Nano-Ca CO₃ were 1.5%,20%and 3%,respectively,FWPC formed a uniform network cell structure andthe density was 0.78g/cm³,the mechanical properties and dynamic thermomechanicalproperties were comparable to WPC,the elastic modulus was slightly increased,andthe heat resistance was slightly lower than that of WPC,achieving light weight andhigh strength to a certain extent.（2）Salix wood powder was treated with alkali to prepare FWPC with PE-HD,the effect of alkali treatment process on the properties of FWPC was studied.The thermal stability of Salix salix powder was improved after alkali treatment,and the surface grooves of Salix Salix were increased,and it was more closely combined with PE-HD.When the concentration of Na OH solution was 12%,the treatment time was 60min and the treatment temperature was 60℃,Compared to FWPC without alkali treatment,the static bending strength,elastic modulus,tensile strength and impact strength are increased by 12.93%,14.92%,18.97%and 9.21%,and the thermal deformation temperature is increased by 3.4℃,which further improves the strength of FWPC.（3）Nano-CB as conductive filler and KH550 as modifier,the Antistatic FWPC was prepared,and the effects of Nano-CB and KH550 on the properties of FWPC were studied.When the content of Nano-CB and KH550 is 8%and 4%,the mechanicalproperties of FWPC were relatively high,and the logarithm values of surface and volume resistivity reach 8 and7,which reach the requirements for the antistatic material.After adding modified Nano-CB,the heat release rate of FWPC was reduced,and the oxygen index reached 21.8%.The carbon layer formed by combustion could block oxygen and heat transfer,thereby inhibiting the oxidation reaction and thermal decomposition reaction of FWPC,and improving the flame retardant performance to a certain extent.（4）APP/ZB as synergistic flame retardant,the flame retardant and antistatic FWPC was prepared,and the effect of APP/ZB addition and ratio on the properties of FWPC was studied.When APP:ZB=4:1 and the total addition amount was 20%,the mechanical properties and heat resistance of FWPC were decreased,the antistaticproperties have no obvious change,the thermal stability was greatly improved,the oxygen index reached 27.3%,the heat release and smoke release rates decreased,the CO yield decreased significantly,the surface of the carbon layer was uneven after FWPC combustion,and the flame retardant and smoke suppression properties of the composite were improved.（5）Comprehensive analysis and selection of the best flame-retardant and antistatic FWPC preparation process:AC,Zn O and Nano-Ca CO₃ added at 1.5%,20%and3%respectively;alkali treatment process:Na OH solution concentration was 12%,treatment time was 60min and treatment temperature was 60℃;modified Nano-CB addition amount was 8%;total addition amount of synergistic flame retardant APP/ZB was 20%,and the mass ratio was 4:1.