Development of Wood Plastic Extrusion Technology

Wood plastic composites (WPC) are a new type of composite material made by extrusion molding process using wood or cellulose as the base material and plastic (including the use of various plastic substrates) as the main raw material. It is a new generation of recycled materials. In recent years, China has invested a large amount of manpower, material resources, and financial resources to accelerate the development and application of wood plastic products. In addition, with the advocacy and promotion of environmental protection, circular economy, and sustainable development, the prospect of the wood plastic composite industry is attractive, and its development is advancing rapidly.

Plastic templates are modified and extruded from wood fibers or plant fibers, reinforced with processing aids, and have the advantages of both wood and plastic components and properties, replacing wood. Wood plastic composite materials, an emerging environmentally friendly material product, are receiving increasing attention and recognition worldwide, with their production and usage increasing rapidly year by year. Currently, global production exceeds 2 million tons. Among them, China's production ranks first with 900000 tons, followed by 700000 tons in the United States, 200000 tons in Japan, and 200000 tons in Germany and other regions. Many countries have invested efforts to accelerate the pace of development and application, especially in the production of sheet metal, which is known as a "hot topic".

The development trend of extrusion molding technology for wood plastic composite materials

(1) Firstly, develop specialized equipment. On the basis of traditional equipment, technological transformation is carried out to develop specialized equipment suitable for processing wood plastic composite materials.

(2) Develop molding processes. Develop foaming process technology to reduce costs and expand the applicability and field of materials.

(3) Develop specialized and functional additives. Such as compatibilizers, modifiers, colorants, light stabilizers, antibacterial preservatives, etc., transform products from low added value to high added value, and improve cost-effectiveness.

(4) Developing from single extrusion molding to composite co extrusion molding. If steel and aluminum are used as the main substrate, wood plastic materials are wrapped around the periphery to improve strength, stiffness, aesthetic effect, and anti-corrosion performance.

(5) Continuously expanding the range of raw material selection. Currently, wood plastic composite materials are mostly composed of single component plastic resins (such as PE, PP, PVC) and wood fibers. As is well known, recycled waste plastics are a mixture of various plastics, which is difficult to separate and costly. How to use multi-component mixed recycled waste plastics to directly composite with wood fibers to reduce costs and improve the effective utilization of resources will become a new research direction. For example, developing a "universal compatibilizer" that mixes various recycled plastics to solve the high cost of separation.