Abstract:

The natural wood Alder was mainly impregnated by vinyl monomers, which mixed in with acrylonitrile (AN), methyl methacrylate (MMA) and acrylic acid (AA) that produced ternary polymerization (AMA) in the experiment. The new-style macromolecule organic polymers material (AMA-wood) was made by thermochemical manufacturing processes. The experimental method below includes the wood impregnation with vinyl monomers by full-cell pressure mehtod and the heat treatment of impregnated wood by heat-initiator method producing vinyl WPC. At the same time ZnCl₂ adding into the cell walls activated Alder. Studies probe some of the physical-mechanical properties and forming behavior of wood polymer composite material by the national standard (GB1927-1943). Other operating properties such as graft loading, microscopic structure have been considered and compared with those of natural wood by means of FTIR and scanning electron microscope. The data presented suggest that physics-mechanical properties of WPC-Alder are much better than in unmodified wood. Density, compressive strength parallel to grain of wood, bending strength, static bending, hardness of cross section, hardness of radial section, hardness of tangential section are among these, which is increased by 59.8%, 76.7%, 90.4%, 22.2%, 102.3%, 153.6%, 152.2% respectively. The water absorption of AMA-wood is 56.7% lower, as well as the swelling of AMA-wood 19.0% lower than that of natural wood.

Key words: Alder(Alnus nepalensis D. Don), Wood polymer composites (WPC), Vinyl monomers, Physical properties, Mechanical strength