Wood compounding process

Compounded WPC pellets are an expensive feedstock option. However, the high initial cost is offset by the fact that these can be molded with less expensive and less complex machines without the need for any additional processing and specialized handling equipment for wood flour. A number of companies have set up plants to produce compounded WPC pellets to sell on to plastics processors. In the compounding process, the filler (wood flour) and additives are dispersed in the molten polymers to produce a homt eneous blend. 

Recent basic research has turned up new approaches for innovative materials combining elements of, and integrating the advantages of, wood and synthetic plastics. Lignin is one of the main components of this new class of plastic-like, wood-like biocomposites. The resulting mixture of lignin, natural fibers, and additives is a compound processable as a thermoplastic. The processed materials are short fiber composites. Arboform is a trade name for this class of compounds. 

Melamine Melamine and formaldehyde Coatings, moulding compounds, wood materials processing, friction linings, textile auxiliaries... 

Wood plastic composites (WPCs), which are produced from wood flour and TP, are used widely as industrial material in the fleld of biocomposites. WPC is included under the category of the filler for filling plastic material, which includes inorganic materials, such as sihca, talc, and calcium carbonate. Therefore, its method of production is also based on the method used for fillers for filling plastic, divided into the compounding process that makes molten mixture of wood flour as filler and... 

Figure 5.29 Fioccuiation of the wood flour in compound process.

A direct extrusion process without wood flour and plastic having to pass through the compound process was introduced in recent years (Figure 5.38). This process is characterized by the presence of a zone of full mixing inside the extrader. It is expected that the development of the extrusion machine will move forward corresponding to the specific features of the WPCs, with an expansion of the WPG market... 

Organic compounds are a major constituent of the FPM at all sites. The major sources of OC are combustion and atmospheric reactions involving gaseous VOCs. As is the case with VOCs, there are hundreds of different OC compounds in the atmosphere. A minor but ubiquitous aerosol constituent is elemental carbon. EC is the nonorganic, black constituent of soot. Combustion and pyrolysis are the only processes that produce EC, and diesel engines and wood burning are the most significant sources. 

---