Research On Forming Process And Properties Of Biomass Fiber/Waste Plastic Foamed Complsite Material

For now, WPC has poor toughness, plastic, large density and so on. It’simportant to study the interfacial compatibility, foaming and molding process,the preparation of biomass fiber/recycled plastic foaming composite material,for improving the mechanical properties of WPC, and reducing defects and costof WPC. This research can reduce environmental pollution and a wide range ofcosts through using waste plastics, in order to improve the market developmentof WPC and be widely used.First of all, we improves the interfacial compatibility and toughnessbetween biomass fibers and waste plastics through experimental on themodification of the waste matrix, different kinds of wood fiber, the type andcontent of coupling agent, and the elastomer type and ccontent etc, then theresults show that:(1)The modification of the waste plastics, to add20%new material HDPE,can improve the interfacial compatibility and comprehensive mechanicalproperties of WPC.(2)To improve the interfacial compatibility of composites, PP-g-MAH isbetter; on the aspect of improving the toughness of composites, SBS is better.The influence of nano CaCO3content on impact strength of composites is moreobvious, the addition of6%nano CaCO3can greatly improve the toughness ofthe material.(3)The content of PP-g-MAH, straw powder, SBS have different degreesof influence on impact, tensile and bending strength of fiber/waste plasticscomposite. The effect of straw powder content on the impact strength，thebending strength and tensile strength of composites is better. (4)Comparing the mechanical properties of fiber/waste plastics composite,the optimum combination: the content of SBS is10%, the content of strawpowder is30%, the content of PP-g-MAH is4%.Second, we studied the density, impact, tensile and bending strength ofbiomass fiber/waste plastics foaming composite through a large number ofstudyings on the content of AC foaming agent, different kinds of wood fiber, thespecies and content of coupling agent and elastomer etc, then the results showthat:(1)After adding foaming agent, comparing with “flat”, then toughness(impact strength) increased and density dropped substantially.(2)On the aspect of improving the mechanicl properties of the foamingWPC, PP-g-MAH is better, and when the content is4%, WPC has goodinterfacial compatibility; on the aspect of improving toughness, SBS is better,and when the content is15%, it has good mechanical properties; when nanoCaCO3content is4%, it also has good mechanical properties.(3)The content of AC foaming agent, straw powder, SBS have differentdegrees of influence on impact, tensile and bending strength of biomassfiber/waste plastics foaming composite. The effect of AC foaming agent contenton the impact strength and the bending strength of composites is better. Theeffect of straw powder content on tensile strength of composites is better.(4)For the comprehensive mechanics properties of biomass fiber/wasteplastics foaming composite, the optimum combination: AC foaming agentcontent is2%, the straw powder content is35%, the content of SBS is15%.Third, we successfully makes the foaming WPC and biomass fiber/wasteplastics foaming composite through extrusion, and we studied the densitythrough AC foaming agent content, different kinds and content of elastomer ofthe new material and waste plastic, then we get the following conclusions:(1)After adding foaming agent, comparing with “flat”, then densitydropped substantially.(2)Adding SBS is more conducive for the foaming.(3)When the SBS content is5%, the density of the composites is relativelyminimum, foaming effect is best.The last, according to analyse and summarize the process factors of composite material foaming effect and mechanical effect in experiments, and theresults are as follows:The collected waste plastics have many impurities. Plant fiber should bedrying, and coupling agent shoud pretreat before extrusion. The extrusionprocess of aggregates will appear that aggregate surface roughness, aggregateinternal being air pocket which are related to material barrel temperature, headtemperature and screw speed. Injection molding process will appear performanceand appearance problems, process problems which are closely related to thematerial barrel temperature, injection pressure and the the temperature of mould.Extrusion process also appears performance and appearance problems which areclosely related to the barrel temperature, plastic temperature, screw temperature,pressure, extrusion rate, and artificial cutting parts etc.