Wood wastes and plastics have been a major environmental concern all over the world. And Plastic has become the biggest problem owing to its waste generated in large amount. Plastic has non-biodegradability property. Similarly, wood with some less amount where it is reducing forests and trees for various applications are ultimately generating the wastes mainly are either disposed or burned form. But the combination of wood and plastics offers potential for the provision of high-value wood plastic composites (WPC). Thus, the appreciated aesthetic effects of wood can be transferred to the world of plastics processing. The wood, in the form of fibers, is usually based on industrial wastes that can be ground. When the loading of wood fibre increases, the cost of the final composites is reduced. Compared to wood, WPC can have a longer service life with less need for maintenance, less water absorption, better dimensional stability and less bio deterioration. WPC can be used as a substitute for wood in a variety of applications, including decking, benches, marina boardwalks, and window and door profiles. The WPC’s performance can be optimized by controlling the raw materials used (type and quantity of wood and thermoplastic polymers), the processing, and the additives. For common WPC applications, the more important properties are mechanical strength, stiffness, impact resistance, density, and color. In terms of color characteristics, the demands for WPC include materials that do not stain and can provide a grained natural wood look. The consumer market is looking for more color variety, especially for dark colored woods. A great diversity of plant residues has been used in WPC, due to the low cost, high environ-mental acceptance, and good sustainability features.
Types of Wood plastic composite
Polypropylene is a semi-crystalline polymer that is used extensively due to its unique combination of properties, cost and ease of fabrication. All grades consist of polymer, a neutralizer and antioxidants. Polypropylene can be processed by a variety of fabrication techniques like film or sheet extrusion, multifilament, non-wovens, injection molding, blow molding and profile extrusion.
PVC comes in two basic forms such as flexible and rigid. It can be made flexible by addition of plasticizers (phthalates) and can be used in plumbing, electrical cable insulation etc.
Polyethylene is a thermoplastic which is comprise of chains of the ethylene and monomer. It is mostly used for plastic carry bags. Polyethylene is used for the production of water bottles and plastic milk cartons. There are three type of Polyethylene such as Low Density Polyethylene, High Density Polyethylene and Linear Low Density Polyethylene. Polyethylene is composed of two elements such as carbon and hydrogen.
Advantages of WPC
The most important factor is that this composite can be manufactured with fully recycled materials. Other advantages have been strength points including the resistance in opposition to biological deterioration especially for outdoor applications where untreated timber products are not suitable, the high availability of fine particles of wood waste is a main point of attraction which guarantees sustainability, improved thermal and creep performance relative to unfilled plastics where It can be produced to obtain structural building applications including: profiles, sheathings, decking, roof tiles, and window trims.