Study On The Technology Of Composite Manufactrring For Strengthened Poplar Veneer

By the way of wood modification, especially strengthened wood, the natural defects of wood can be improved, at the same time endowing wood some specific function; Which can expand the field of application of wood, improve the wood quality of fast-growing forest plantation and achieve the purpose of using poor wood as high-quality wood. It's an effective way to solve the problem that precious wood is in shortage and in under provision. This paper mainly studied the technique by which the wood composite material is manufactured by strengthened poplar veneers. Non-saturated vinyl monomers impregnate into poplar veneers, and then the monomers polymerize as a kind of macromolecule polymers through the function of initiators. Finally through the way of heat pressure strengthened poplar veneer composite material is manufactured by wood adhesive. The mechanics property of abrasion resistance, surface hardness, bending strength, modulus of elasticity (MOE) are improved, comparing with untreated polar veneers. This kind of strengthened wood composites improve the natural defects, expand the field of application and extend the usable life of poplar.OIn this study we first impregnate ternary polymerization: Styrene(St), Methyl methacrylate (MMA), Vinyl acetate (VAc) into poplar veneers together, and add initiators to make alternative copolymers. This structure is superior to homopolymer that formed by single monomer in function, which is because alternative copolymer changes the mechanical and chemical properties of homopolymer to a large extent. As for experimental method orthogonal design is employed to design the component ratio of the mixed resin liquid, the impregnating process of monomers, the selection of initiators and the process of heating press. The experimental data is researched by variance analysis. The performance targets of the strengthened poplar veneers are tested according to the testing way to the chemical and mechanical performance features of the wood-base panel in National standard GB/T17657-1999. On the means of analysis, the modern advanced testing technique of Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM) are used to analyze the chemistry constitutes of the strengthened poplar veneer qualitatively. From experiments the results are followed:1) While selecting the mixed resin liquid, Conversion Loading decide the performance of the resin liquid.2) By the way of pressure to treat wood, Monomer Loading depends on press and pressure time. Monomer Loading is the best parameter to investigate the effectiveness of impregnation under the optimum ratio of the mixed resin liquid. The optimum process condition is that the press is Fy3, the pressure time is ty2. And the Monomer Loading will get 129.62 percent3) The Conversion Loading of the three monomers lies on the degree of monomers turning into macromolecule polymers. The higher is Conversion Loading, the higher is Ternary polymerization. And the Conversion Loading is relative to the species and density of initiators, and the polymerization temperature and heating time.