Production Lines (direct extrusion):• Cincinnati Konos 38 & Fiberex 58 (up to 80kg/h) Lab scale• Conical co-rotating twin-screw extruder (up to 250kg/h) Production scale

Raw material: • Post industrial wooden waste• Polymer matrix materials: pre-mixed PVC (Solvay) dry-blend, PP (Borealis)

General condition:• Melt quality(1 -5): 3 (sufficient plasticized in venting zone)• Smell: minor smell (like in typical industrial wood-production plants)• Assessment of extruded products: mostly perfect samples• Uncolored sample color: Medium to dark brown

Proceedings of the 1st International Conference on Processing Technologies for the Forest and Bio-based Products Industries. Salzburg/Kuchl, Austria, 07-08 October 2010

Post industrial wooden raw material as natural fiber base for wood plastic composites (WPC) based on PVC and PP matrix materialDipl.-Ing. Sven WOLF1,2, Ing. Mag. Dr. Peter HAUSBERGER1, Ing. Mihaly SZAKACS, BSc.1

1FH-Technikum Wien, Institut für Advanced Technologies, Hochstädtplatz 5, Vienna, AUSTRIA 2extruwood GmbH, Industriepark 22, Pasching, AUSTRIA

What is WPC?„Wood plastic composite“ consists of:•Wood fibers (50-80%)•Additives (up to 5%)•Polymer matrix material: PE, PP, PVC(complementary percentage)

What is „post industrial wooden raw material“?Reprocessed wood from used products like:•Medium/High-density fiberboards (MDF/HDF)•OSB: Oriented strand board•Three-layer slab, …

Background Design of experiments

Target: To prove the concept of using post industrial wooden raw material for exterior WPC profiles

Selected results

DensityWPC: between 900 and 1400 kg/m³ MDF: between 600 and 800 kg/m³)WPC have a higher density than its single components due to compacting and compression of porous wood structure (cavities are filled with matrix polymer)

Test profile for the productionof material samples on lab scale:

TRIAL PLAN

PVC WOOD CONTENT PP

50 % 50 %45 % 55 %40 % 60 % 40 %

70 % 30 %75 % 25 %80 % 20 %

Advantages of using post industrialwooden raw material for WPC:• low price• large quantities• stable in quality• low cost on logistics • well documented origin

Challenges• contamination with resin• higher dust content

≥60% outdoor-use => important technical issues:Weatherability, water absorption, fading

Growing market demand leads to increased consumption of tropical woods. Usage of WPC can substitute this demand

Outlook

Essential Properties:• Improved Strength (against Plastic)• Reduced swelling and absorption of water (against wood) • Wooden-like visual appearance and haptic

This project was supported by the EU under the CORNET directive

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Water absorption:

With optimized production and recipe formulations, post industrial waste wood and PVC based WPC will come close to natural wood in many properties

Especially due to high strength and reduced creep behavior constructive wood engineering might be possible with those developments

Creep behavior:

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Optimization of mechanical strength by processing and recipe:

Decking; 57%

Siding; 11%

Other applicatons; 32%

WPC product market share EU

Decking; 40%

Molding & trim; 29%

Landscaping & outdoor products;

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Fencing; 10%

Other applications; 10%

WPC product market share US

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