1.1 Definition of wood plastic composite materials
Wood Plastic Composite (WPC) is a booming new type of composite materials at home and abroad in recent years, which refers to the use of polyethylene and polyvinyl chloride instead of usal resin adhisive, mixed with more than 50% of the rice husk and wood powder, straw and other waste plant fiber to shape new wood materials by extrusion,molding,injection molding and other plastic processing to produce plates or sections. These products are mainly ueed for building materials, furniture, logistics, packaging and other fields. The palstic and wood powder are mixed at a certain ratio then extrude to the plate, which is called extrusion wood plastic composite board.
1.2 The main characteristics
The basis of wood plastic composite materials are high-density polyethylene and wood fiber, which determins their own characteristics of both wood and palstic
1) Excellent process ability
Wood plastic composite materials contain plastic and fiber, therefore, it has the processing performance that is similar to timber so it can be sawed, nailed, planed by using carpentry tools, meanwhile, the ability of nail holding of WPC products is much better than that of other synthetic materials, and mechanical properties of them are better than that of wood materials. The ability of nail holding of WPC products is 3 times than that of wood, 5 times than that of particleboard.
2) Excellent property of strength
WPC materials possess better elastic modulus because of containing plastic. In addition, because the embedded fibers and plastic are fully mixed, it has physically mechanical properties of compression and bending, which are similar to hardwood, and its durabilty is much better than that of ordinary wood materials. The hardness of surface treatment is 2-5 times than that of general wood.
3) Anti-water, anti-corrosion with long service life
Compared with wood, WPC material and its products can be strong acid and alkali resistance, anti-water, anti-corrosion, anti-bacteria, anti-moth, anti-fungus with long service life of over 50 years.
4) Excellent adjustable performance
Polymerization, foaming, curing, modification and other changes happen to palstic by using additives, which not only changes the density and strength of WPC materials, but also achieves some special requirements, for example, anti-aging, anti-static, flame retardation.
5) It has good qualities of UV light stability and painting.
6) Its biggest advantages is to turn waste into treature, and can be recycled 100% reproduction. It can be decomposed, which does not cause white pollution. Thus WPC material is the real green environmental protection product.
7) Extensive sources of raw materials
The main raw material of WPC material is high density polyethylene, and wood fiber can be wood flour, bran or wooden fiber, in addition, a small a mount of additives is necessary
8) It can be made to any shape and size according to the reqiurements.