Wood Plastic Composites - New property profile by refiner fibres

The mechanical properties and thus the application area of wood plastic composites with a wood content > 60 % shall be explicit increased by means of long wood fibres. The realization of a technological direct feeding system in extrusion process will enable an innovation jump of this wood like material.

Short Description




Wood Plastic Composites (WPC), the wood like materials consisting of wood shavings and 15 to 40 % thermoplastic resin which are processed by manufacturing technologies of the plastics industry, have been strongly established in the European market. The prediction for this material group is a strong increase in the Austrian polymer market, regarding to the an-nual increasing sales volume in the biggest WPC market in North America in the next years. Whereas the American WPC market is dominated by Polyetyhylen (PE) and Polyvinylchlo-ride (PVC) the more environmental friendly polyolefins mainly Polypropylene are preferred in Europe. One of the weaknesses of these material formulations is the serious decrease in impact strength with increasing wood content. Thus new WPC applications tend into the di-rection of lower wood content to offer ambitious products with sufficient toughness.

In the view of an increasing material-oriented use of renewable raw materials the aim of the development of wood plastic composites must be the increase of the wood content. Thereby the necessary enhancement of the functionality of the wood in the compound is only possible by the use of long fibres of wood, the so called “Refiner” fibres. At present the wood form is procedural limited to oblong/cubic particles. Aim of this project is to investigate new economic technologies for the possibilities of Refiner fibres as reinforcement fibres for extruded and injection moulded WPC. This is implemented by cooperation of machine manufacturers, a WPC producer, and a scientific facility.

In the first year the specification of refiner fiber compounds in different processes was tested, which is the basis for the technological approach to realize the direct extrusion technology. The expected specification profile of the gained WPC compounds from the direct extrusion process did not differ significantly to the one of an extrusion compound with pelletized fibers. From the economical point of view the single-step-process is the favourite one.

A new and unique process for feeding and dosing of this fibers has been developed and a prototype was implemented in an fibre-extrusion line.

Project Partners

Project management

Dr. Reinhard Forstner
Transfercenter für Kunststofftechnik GmbH

Project or cooperation partner

  • Mag. Erik Sehnal,DI Mathias Daniel
    Cincinnati Extrusion
  • DI Klaus Feichtinger, Georg Weigerstorfer, Roland Huber
    EREMA - Engineering Recycling Maschinen und Anlagen GmbH
  • Mag. Michael Theurl, DI Michael Oberloier, Rudolf Müller
    Theurl Leimholzbau
  • Dr. Wolfgang Stadlbauer, DI (FH) David Wimmer, Franz Hartl, Ing. Karl Moser, Ing. Andreas Gösweiner

Contact Address

Dr. Wolfgang Stadlbauer
Transfercenter für Kunststofftechnik - UAR GmbH
Hafenstraße 47-51, 4020 Linz
Tel.: +43 (7242) 2088 1002
E-Mail: wolfgang.stadlbauer@uar.at