Development of the hottest PVC wood flour composit

Development of pvc/wood flour composite micro foaming new material

according to the national "Ninth Five Year Plan" development plan and the long-term goal plan of "replacing wood with plastic, replacing steel with plastic, saving resources and protecting the environment" in 2010, the Institute of plastic machinery and plastic engineering of Beijing University of chemical technology and Shanghai Chende plastic products cooperation company have successfully developed pvc/wood flour composite new material and its product production technology after years of research and research

it is characterized by adding% wood fiber filler (wood powder) and various processing aids such as stabilizer, modifier, lubricant, foaming agent, etc. to PVC plastic raw materials. After being mixed by a high-speed mixer, wood plastic particles of different specifications and grades are prepared by a special granulation and extrusion mechanism. Finally, PVC wood plastic composite micro foaming decorative profiles of various shapes are produced by molding extruders, molds and different processes. The key technology is to ensure a high filling amount of wood powder, so that the products have low production cost and high performance. PVC door and window handle jg/t 124 ⑵ 000194 PVC door and window hinge. At the same time, due to the surface treatment of wood powder, it can be well wetted by PVC resin to achieve the best bonding interface. The project is in line with the spirit of the new project of the country, which should focus on the development of material saving, energy saving, cellulose chemistry and industry, which began more than 160 years ago, meet the market needs and fill the domestic gap requirements, and comply with the long-term technical national policy of "replacing wood with plastic" and "replacing steel with plastic"

pvc/wood flour composites have developed rapidly and are gradually replacing traditional wood products with their advantages of high toughness and low cost. However, after PVC and wood flour are compounded, its ductility and impact resistance are reduced, the material is brittle, and the density is nearly 2 times higher than that of traditional wood products. These factors limit its wide use. In order to eliminate the above shortcomings, the processing price of incoming materials is usually increased by adding impact modifiers, but this method is almost ineffective in improving the ductility and reducing the density of products. In recent years, the research and development direction has turned to micro foaming molding technology. The foamed pvc/wood flour composite can passivate the crack tip and effectively prevent the crack expansion due to its good bubble structure, so as to significantly improve the impact resistance and ductility of the material, and greatly reduce the density of the product. With the advantages of low cost, high efficiency, short time-consuming and easy industrialization, extrusion micro foaming has become the main method of forming foamed plastics

I. characteristics of pvc/wood flour composite micro foaming new material

PVC/wood flour composite extruded micro foaming products have excellent characteristics of both wood and plastic. The products have achieved the effect of real imitation wood. The production cost is also lower than that of wood products. Its emergence will bring a revolution to the wood products industry, especially in today's resource shortage and soaring raw material prices, it has brought new vitality to the plastic processing industry. Its characteristics are as follows:

1. It is waterproof

the water absorption of the wood itself is as high as%, but after surface treatment, a layer of polymer film is formed on the surface of the wood powder. At the same time, the wood powder is also tightly wrapped by polymer materials. The test results show that the water absorption of this material is less than 2%, which has a certain waterproof performance

2. It has flame retardancy

this is related to the molecular structure of PVC in the material, because the content of chlorine in the molecular structure of PVC is as high as 56%, and chlorine itself has the function of self extinguishing from fire. Generally, the oxygen index of this material is up to 35

3. Good mildew resistance

because wood flour is surface treated and coated with polymer materials, it lacks an environment for mold breeding. At the same time, during the treatment of wood flour, the surface is adsorbed with anti mildew agent, which also improves the anti mildew performance of the product

4. Strong woodiness

because the content of wood powder in this material can reach%, and through micro foaming, the product density can be controlled at 0 0g/cm, which is very close to the density of wood, and the internal organization is relatively loose, with a natural woodiness. Various colors and shapes can be mixed to avoid the trouble of color difference

5. Strong practicability

it has all the safety properties of solid wood: nailable, planable, and paintable (paint free is optional). It is especially suitable for large-scale and industrialized rapid decoration, which is fast and convenient

6. Corrosion resistance:

wood flour itself has poor corrosion resistance, but after being coated with polymer materials, due to the good acid-base inertia of PVC itself, this material has good corrosion resistance

7. Good electrical insulation

II. Application prospects

with the improvement of people's living standards and the development and popularization of housing projects, the market for home decoration is becoming larger and larger, the demand for decoration materials is gradually increasing, and the quality requirements are becoming higher and higher. As a high-grade decorative 1.5875mm steel ball decoration material, wood plastic composite decorative profiles have great market potential. As a new type of wood substitute, it can be widely used in the fields of architectural decoration and packaging, such as corner lines, particleboard strips, curtains, door buckets, floors, fences, skirting boards, art boards, shutters, mirror frames, photo frames, window frames, toys and ordinary furniture supplies, indoor doors, etc. the vast majority of indoor and outdoor decorative building materials can be made of PVC wood plastic materials. In particular, it is worth pointing out that the processing of decorative materials with logs not only brings fire hazards, but also easy to mildew and moth, which brings potential safety hazards. PVC wood plastic completely discards the shortcomings of logs, improves the shortcomings of logs, and retains the unique woodiness of logs. Compared with wood, wood plastic materials have waterproof and fireproof functions, so they can be used for the decoration of kitchens, washrooms, etc. At the same time, PVC wood plastic materials can produce products of different grades, specifications and colors according to different wood species and colors. Because the production process adopts extrusion molding, automatic continuous production can be realized, and the length can be determined arbitrarily, which is beyond the reach of logs. Wood plastic products have attracted extensive attention in the world. They are known as green and environmentally friendly new materials and will have broad prospects for development

VI. conclusion

in recent years, the global forest resources are increasingly exhausted, and the social awareness of environmental protection is rising day by day, which also puts forward higher requirements for the application of wood. Wood plastic materials are basic industrial raw materials, which can produce various building decoration materials that widely replace wood, which can not only save forest resources, but also protect the environment. This material has excellent properties such as low specific gravity, high strength, weather resistance, corrosion resistance, heat insulation and insulation, and it has sufficient raw materials, diverse varieties, adjustable colors, texture close to wood, simple maintenance, and significant economic and social benefits. Therefore, the development of this new type of green environmental protection material has extremely practical and far-reaching significance