One of the constituents of wood plastic composite materials
Wood fiber raw materials
Compared with mineral fibers, plant fiber raw materials have the characteristics of wide sources, low prices, reproducible processing, natural regeneration, and biodegradability. In addition, plant fibers have shown good mechanical properties in thermoplastics as a reinforcing material.
The most commonly used raw material is of course wood, and various wood processing residues can be processed into short fibers or fine particles, powder, sawdust, and sanding powder can be used directly. In addition, agricultural fiber raw materials also occupy a certain proportion. Especially in Europe and China, most factories use agricultural raw materials such as straw and rice husk.
Coupling agents and additives
As a structural material, wood plastic composite material is mainly used as a load-bearing or sub-bearing structure, so it is required to be lightweight, high in strength and stiffness, and able to withstand a certain temperature. When the wood plastic composite material is under load, the interface of the composite material should be able to transfer the stress on the matrix to the reinforcement, which requires the interface phase to have sufficient bond strength.
Coupling agents are substances that can improve the interface characteristics between fillers and polymer materials. There are generally two effective functional groups in its molecular structure. In this way, the coupling agent has a bridge effect, which can improve the interface properties of polymer materials and fillers, improve the interface adhesion, and thereby improve the performance of wood plastic composite materials.
The composition of WPC also needs to add a small amount of additives to improve processability and useability. Light stabilizers, pigments, lubricants, antioxidants and other additives used in general plastic processing can also be used in WPC manufacturing.