Wood Plastics

Task

The extrusion of plastics with a high content of wood fibers has been known for quite some time. The maximum wood fraction in wood plastic composites usually is 70% (typically less than 50%). The process technologies and tools used so far are not suitable for composites with a very high wood fraction as the resulting quality of the profiles is insufficient and the low output is economically inefficient.

Innovation

The present project aimed to increase the wood fraction to more than 90%. In addition, researchers developed a new process and tool technology, which ensures a high quality of the profiles and, at the same time, permits an economically efficient production of profiles. In order to further improve economic efficiency, researchers designed a device that permits to process wood fibers or chips together with several other components (additives, pigments, starch) in the extruder and without any additional process stage.

Benefits

The main component of this newly developed composite is wood fiber, which means that a large part of plastic material can be replaced by a renewable raw material. Using wood fibers or chips in a high-quality composite material will considerably increase the value-added of wood fibers and chips which otherwise can only be used as by-products (e.g. pellets, chip and fiber boards).

Results

Optimized formulations for new wood composites, systematic property matrices of the new materials, new technology to control the wood fraction fed into the extruder, adapted and optimized processing and tool technology, clearly improved profile quality through newly developed tools, improved economic efficiency of the production process.

Fotoquelle: Petra Blauensteiner