Study On Preparation Of FRP Waste/Straw Fiber Wood Plastic Composites

The waste agriculture and forestry straw has brought serious environmental pollution. Meanwhile, our country is facing a serious shortage of timber. The thermosetting fiber reinforced plastics(FRP) was crosslinked molecular chain in the manufacturing process.The thermosetting fiber reinforced plastics cannot remelt or dissolve, so it is difficult to be recycled. Fiber reinforced thermosetting plastics(glass fiber reinforced plastic(GFRP) and carbon fiber reinforced plastics(CFRP))waste, and the straw fiber instead of wood fiber were used to the prepare the PVC based wood plastic composite(WPC) in this paper. We found a new way to solve the treatment problems of waste agriculture and forestry straw and waste thermosetting FRP.In order to improve the interface bonding of straw fiber and PVC resin. First of all, straw fiber was treated with sodium hydroxide solution, and then the mixed waste GFRP and corn straw fiber were introduced into the WPC. The synergistic enhancement effect of glass fiber and corn straw fiber was investigated. In order to further improve the strength of WPC, the KH550 solution was used to deal with waste GFRP. With 30 phr(parts per hundreds of resin) waste FRP, the tensile strength, flexural strength and impact strength of WPC were improved to 25 MPa, 68 MPa and 19 KJ/m2, increased by 33%, 26% and 53% with respect to starting WPC. The results show that there was a good physical interlock network structure among glass fiber of waste FRP, corn straw fiber and poly(vinyl chloride)(PVC) in WPC, which led to the enhancement of mechanical properties of WPC. Physical interlock network structure can effectively improve the mechanical performance, heat resistant performance, waterproof performance of composite materials.AC foaming agent was added to the raw material, the effect on the properties of WPC was researched. WPC distribution within a large number of pores can decrease its density. Smaller pore size were distributed homogeneously in WPC. Corn straw fiber evenly distributed within the resin matrix and was coated by PVC resin matrix. Corn straw fiber has good compatibility with PVC. Research finding, foaming agent is added to the 1.5% of the total weight of WPC; the density of WPC dropped to 0.98 g/cm3; density was reduced by 37%.Recycled carbon fiber(CF) was introduced into wood plastic composite(WPC). The electromagnetic interference(EMI) shielding effectiveness(SE) of WPC in the X-band region(8.2-12.4 GHz) was studied. The effect of different recycled carbon fiber content on the properties of WPC electromagnetic shielding was studied. with the increase of recycled carbon fiber content, the electromagnetic shielding performance was improved. When CF mass fraction reaches 4 wt.%, SE reaches 23 dB.Graphene oxide(GO)-deposited CF(GO-CF) and reduced GO-deposited CF(rGO-CF) were introduced into wood plastic composite(WPC). The results showed that GO-CF and rGO-CF were found to be more effective than CF in providing EMI shielding of WPC. rGO and GO sheets between CF and PVC resin make contribution to improve the EMI SE absorbing ability of the composites. With 4 wt.% rGO-CF and a shielding thickness of 4 mm, a SE of 29 d B was attained. The WPC filled with rGO-CF has a promising prospect in EMI shielding materials.