The current trend of developing environmentally friendly products leads researchers to look for alternative materials in a variety of applications. Wood Plastic Composite (WPC) is becoming popular in many sectors, particularly in construction and automotive, due to the attractive properties it presents compared to traditional materials like wood.
This type of material belongs to the family of bio-composites comprised mainly of cellulosic materials and a thermoplastic polymeric matrix, which can be virgin, recycled, or bio-based.
Generally, the polymers used for this type of composite are Polyethylene (PE), Polyvinyl chloride (PVC), and Polypropene (PP).
Regarding vegetable fibres, usually wood flours (pine, maple, oak, dried fruit husks) or fibres (rice, wheat, or hemp straw) are used. Up to 60%-70% in weight can be incorporated into the polymer and they can act as a filler or as a matrix reinforcement agent.
Originally wood plastic composites were focussed on non-structural applications, mainly in the automotive and construction sectors.
At present, these areas continue to be of great interest, but they are also present in various sectors such as:
Figure 3. AIMPLAS capacity scheme in WPC.
AIMPLAS has extensive experience in projects with bio-composites and WPC, being able to carry out the complete process of its fabrication in their facilities, from the design of the product, optimisation of the formulation and extrusion, and injection of the composite.
They have the ability to develop it in 1 “one-step” stage, direct extrusion (with a co-rotative or counter-rotative, twin screw extruder, according to the polymer base and the profile to obtain), or in 2 stages combining the technology of compounding and extrusion/injection (single screw).
With regard to projects, AIMPLAS has conducted nationally and internationally subsidised projects and private projects with companies. Products with very varied properties have been studied and developed from auxiliary office furniture, coat hangers, interior lorry parts to profiles for outdoor use.
Marta Pérez Argilés
Construction and Renewable Energies researcher