The main focus of Application Group 3 was the development of new natural thermoplastic and thermosetting binders suited for injection moulding or extrusion processing.
Wood Polymer Composites (WPC) made of wood fibres and thermoplastic binders such as polypropylene or PVC have gained an attractive market share in Europe, mainly for decking applications, but are suffering from durability problems. To address this issue, we suggested using wood fibres modified with furanic compounds, obtained from sawing residues of Application Group 1 products, in combination with natural binders. By specific esterification of lignin, we succeeded in formulating a good binder. In parallel, we also investigated the potential of PLA in combination with furfurylated wood fibres. Both esterified lignins and PLA are well compatible with furfurylated wood fibres. WPC samples produced on lab scale, using modified wood fibres and esterified lignins or PLA have comparable mechanical properties to conventional WPC’s, but a significantly better resistance to decay.Outdoor Fence Panels.
In the Alpine region, traditional roof shingles are made of wood. These shingles are quite expensive and are complex to install. Within the Ecobinders consortium, we developed a novel injectable wood shingle, based on compounds of wood flour and lignin. We choose a special design to significantly increase convenience and reduce the installation cost. This could be achieved by combining more shingles in 1 mould, designing a clip system and reducing the number of nails needed for fixation. Such shingles are also suited for wall covering. Over the 3 years of the project we overcame technical problems such as flow properties of the compounds, impact resistance, smell issues…, resulting in a design and formulation that is now ready for industrial production. Our shingles will be a cheaper and more convenient alternative to wooden shingles, based on forest waste and available in different colours and textures. Outdoor testing of these novel shingles is still in progress.Composite Decking Materials.
Surprisingly, we found out that compounds made of lignin, cellulignin and furan resins have excellent electrical insulation properties. These thermosetting compounds are suited for extrusion and injection moulding. They can be used for connectors, spacers, printed circuit boards… as natural alternatives to phenolic resins or epoxy resins. The technology is developed at lab scale. Samples and prototypes have been fully characterised, highlighting the insulation properties, but also mechanical properties such as strength and impact resistance, which need to be improved before future upscaling.
We finally also tested furanic compounds as thermosetting binders for cork stoppers. Unfortunately, these binders are too brittle and not registered for food contact, limiting the possibility to use them in the market.Wood Composite Panels.
The Ecobinders project resulted in the development of a new range of natural binders, both thermoplastic as thermosetting. These binders are available in large quantities and can be used in several applications such as wood industry (durable wood for decking, furniture, window frames…), fire resistant doors and panels, insulating panels, decking and flooring panels, roof and wall shingles, electrical compounds…