What is wood plastic composite - Knowledge

WPC 1.1 definition

Wood plastic composites (WPC) is a new type of composite materials which is booming at home and abroad in recent years. It refers to the use of polyethylene, polypropylene and PVC instead of the usual resin adhesive, and more than 50% of wood powder, rice husk, straw and other waste plant fibers mixed into new wood materials, and then through extrusion, molding, injection molding and other plastic processing technology, Plate or profile produced. Mainly used in building materials, furniture, logistics packaging and other industries. The extruded wood plastic composite board is made by hot extrusion after mixing plastic and wood powder in a certain proportion.

1.2 main features

The basis of WPC is HDPE and wood fiber, which determines that WPC has some characteristics of plastic and wood.

1) Good processability

Wood plastic composite contains plastic and fiber, so it has similar processing performance with wood. It can be sawed, nailed and planed. It can be completed by using woodworking tools, and the nail holding force is obviously better than other synthetic materials. The mechanical property is better than that of wood. The nail holding force is generally three times that of wood and five times that of particleboard.

2) Good strength performance

Wood plastic composites contain plastic, so they have better elastic modulus. In addition, because it contains fiber and is fully mixed with plastic, it has the same physical and mechanical properties as hardwood, such as compression resistance and bending resistance, and its durability is obviously better than ordinary wood materials. The surface hardness is high, generally 2-5 times that of wood.

3) With water resistance, corrosion resistance, long service life

Compared with wood, wood plastic materials and their products are resistant to strong acid and alkali, water and corrosion, and do not breed bacteria, are not easy to be eaten by insects, and do not grow fungi. Long service life, up to 50 years.

4) Excellent adjustability

With the aid of additives, plastics can be changed by polymerization, foaming, curing and modification, thus changing the density and strength characteristics of wood plastic materials, and achieving special requirements such as anti-aging, antistatic, flame retarding and so on.

5) It has UV light stability and good colorability.

6) Its biggest advantage is to turn waste into treasure, and can be 100% recycled for reproduction. It can be decomposed and will not cause "white pollution". It is a real green environmental protection product.

7) A wide range of raw materials

The main raw materials for producing WPC are HDPE or pp. the wood fiber can be wood powder, rice bran or wood fiber. In addition, a small amount of additives and other processing aids are needed.

8) It can be made into any shape and size according to the need.

1.3 scope of application

One of the main uses of wood plastic composites is to replace solid wood in various fields, among which the most widely used is in construction products, accounting for 75% of the total amount of wood plastic composites. See table 1.3-1 for the main application places and uses of WPC.

Table 1.3-1 main application places and uses of WPC

Place