The Basic Knowledge of Wood Plastics
With the strengthening of people’s awareness of environmental protection, Waste wood and plastics with low recycling costs have become a common concern in industry and the scientific community, which has promoted the research and development of Wood Plastic Composite and made substantial progress, and its application has also been accelerating.
Waste wood and agricultural fibre used to be incinerated, and the carbon dioxide produced has a greenhouse effect on the planet, so wood processors are struggling to find ways to turn it into higher-value new products. At the same time, plastic recycling is also the key development direction of plastic industry technology, plastic recycling has become an important basis for many plastics processing industries. Under such circumstances, wood plastic composite materials came into being. Governments and relevant departments all attach great importance to and pay attention to the development and application of this new environmentally friendly material.
Wood plastic composite material combines the advantages of wood and plastic in one, not only have the appearance of the like natural lumber, and overcome its deficiencies, have anticorrosive, moistureproof, mothproof, high dimensional stability, no crack, no warping, etc, then pure plastic hardness is high, and there was a similar to the processability of lumber, for cutting, bonding, with nails or bolted connections, can be painted. It is by virtue of the dual advantages of cost and performance that wood-plastic composites have been expanding their application fields in recent years, entering new markets and replacing other traditional materials more and more.
Wood plastic composite material is mainly used in panel, wall panel, decorative board, building templates, highway noise barrier, seaside road plate with composite pallets, storage, packaging and logistics, also as a decorative border, fences, stair handrail, watch ship cabin partition, office partition, open tables and benches, storage box, flower boxes, activity, car inner decoration (door decorating plate, plate, spare wheel cover, seat, instrument panel, glove box, mask, headrest plug-ins, etc.), is developing the material and laminated, shutters, roof board, etc. Residential and commercial building plank is the biggest users of wood plastic composite, and on the rise, so the wood plastic composite materials processing and structure with the sheet (including different profile) is the most active part of the plastic extrusion industry, demand for double-digit growth rate, and other industrial and agricultural use the beach road board, platform terminal board and other facilities with plank is stable. Because wood is not sea water corrosion resistance, easy cracking and warping, short service life, made of wood plastic composite products have obvious advantages, the U.S. Navy for repair, replacement board costs by $250 million a year, so has launched a five-year, $10 million contract to the wood plastic composites to replace wood development project, shall be borne by the Washington state university. In addition, it was also found in the study that the performance of roofing board used for building by wood-plastic composite material exceeded that of the board, and the cost was 85% ~ 95% of the raw material of wood.
At present, the products which increase the added value of materials are more and more concerned by people. Wood plastic composite materials of environmental protection is the wood shavings, bamboo shavings, rice husk, straw, soybean husk, peanut shell, bagasse crops such as abandoned natural wood fiber as the main raw materials, research focus now mainly concentrated in the polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polystyrene (PS) and other thermoplastic plastic and wood powder, plant straw powder, wood powder as raw materials, such as plants shell after extrusion, injection molding, pressing forming made of composite materials. From the perspective of producing raw materials, the raw materials of wood-plastic composite materials can use all kinds of waste plastics, waste wood and the remains of crops. Therefore, the development and wide application of wood-plastic composite materials can help reduce the pollution of plastic waste and reduce the environmental pollution caused by the incineration of agricultural waste.
The production and use of wood-plastic composite materials will not emit volatiles harmful to human health to the surrounding environment. The materials themselves can be recycled and utilized, which is a new green environmental protection product as well as an ecological and clean composite material.