Wood Plastic Composites An Overview

Presentation Outline

• Introduction to Wood Plastic Composites• Historical Development• Milestones in Commercialization• Technology Status• Benefits of wood plastic composites• Applications• Future markets & business opportunities

Definition

Wood Plastic Composite ( WPC )

Any composite that contains wood & thermoset

or thermoplastic

Thermoset : Epoxy , Phenolics

Thermoplastics: PE, PP, PVC, PS

Introduction

• First Generation WPCs Recycled woodchips / flour & binder

Designed for undemanding applications

• New Generation WPCs

High Performance products

Good mechanicals

High dimensional stability

Complex shapes

Extruded products with high dimensional tolerance

Introduction

“The new generation WPCs are produced by mixing wood flour or fiber & plastics to produce a material that can be processed like a conventional plastic & has the best features of wood & plastic”

Plastic Lumber

• Recycled Plastics

• Extruded profiles

• May / may not include wood flour

• Application – Sleepers on rail roads

Historical Perspectives

• 1900 : Bakelite ( Gear shift knobs for Rolls Royce)

• 1920: Birth of the WPC industry

Marriage of plastic processing

&

forest products industry

Initial Impediments to Growth

• Forest Product Industry Viewpoints– Alien to Plastic materials

– Few common material & equipment suppliers

– Only exposure to vinyl sidings

– Lack of Market Knowledge & application areas

• Plastic Industry Viewpoints– Conversant with mineral fillers & reinforcements

– Aversion to wood & natural fibers

Wood as a filler: Plastic Industry’s Viewpoints

• Low bulk density of wood flour vis-a vis plastics

( 0.5)• Low specific gravity of wood• Low thermal stability of wood• Tendency to absorb moisture

The Turn AroundThe last decade saw

• Greater awareness from both sides• Success of several WPC products• Greater understanding of wood filler• Developments in compounding equipments• Development in additives• Emerging opportunities in large volume building

application sector

Forest Products Industry: Change in Perception

• WPCs :Products with little maintenance• Low maintenance : USP Of WPCs• Forest Product companies : Suppliers of WPCs

Synergize knowledge of wood flour & core competence in building products

Milestones in The Commercialization Of WPCs

Year Company Product

1975 G.O.R., Italy Woodstock patent

1983 American Woodstock

Lear Corporation

50% WF/PP sheets for thermoforming for auto interiors

1990 Strandex Corporation Highly filled WPC extruded profiles& shapes

1991 AERT Later TREX 50 % WF/PE for deckboards, picnic tables etc

1993 Andersen Corporation WF reinforced PVC sub sills for French doors & window lines

Technology Status of WPCs

Market Potential

• Global market size : 320,000MT in 2000

• Expected Volume : More than double in 2005

Wood Filled Composites Natural Fiber Filled Composites

Technology Status Of WPCsMaterial Attributes

Thermoplastic Material End-Use

PE Virgin & recycled Exterior building components

PP Virgin Automotive

Profiles

PVC Virgin Building profiles & decking & windows

Technology Status Of WPCsPolymer Attributes

Selection of Thermoplastic matrix

* Inherent properties of polymer

* Product requirements

* Availability

* Cost

Technology Status Of WPCsAttributes of wood

• Wood flour : Particulate, l/d 2:1 to 4:1• Wood fiber : Reinforcing, l/d greater than 24:1• Commonly used species : Pine, Maple Oak• Typical particle size : 10 to 80 mesh• Price : Indian Rs. 15 to 20/- per Kg• Price : Imported Rs. 35 to 45/-per Kg

Technology Status Of WPCsManufacture & Processing

• Two stage Process: Compounded pellets & shaping

• Commonly Used processing Techniques Sheets & profile extrusion Thermoforming Compression Molding Injection Molding• New Trend In-Line Compounding & Processing

Salient Features of Extrusion of WPCs

• Two stage Process - compound & shaping

• Two Extruders in tandem Twin screw Compounding and shaping

Extrusion of WPCs

New Developments In Equipments

• American Maplan Corp : Counter rotating TSE, conical & parallel for direct extrusion

• Woodtruder American Davis Standard ( Crompton): First Stage drying extruder & side arm extruder for injection of polymer melt into the main extruder. Up to 80 % wood flour

• Wilmington Machinery: 375 tons two stage injection molding for foamed WPCs

Manufacturing Wood / PP Composites

Machinery For Wood PP Composites

Additive Developments Aid Growth of WPCs

• Tailor-made lubricants

• Non stearate & compatibilizer package

• Special HALS

• Antimicrobials

• Blowing agents

Wood Filled PP

Application Benefits

• Improved dimensional stability - increased strength

• Lower processing temperatures - less energy used

• Increased heat deflection temperature - reduced thermal expansion

• Up to 30% reduced cycle time for injection moulded products - increased productivity

• Approximately 10 - 20% lower specific gravity - lighter products

• Reduced shrinkage - lower internal shear in pultrusion application

• Low volumetric cost

ConventionalFillers Vs Wood Filler

AWF Wood Flour Weight Savings

Specific Gravity40% Filled Resin -

Polypropylene

Flexural MOE Versus %

Wood Flour2.0 2.2

3.23.8

4.5

0.0

1.0

2.0

3.0

4.0

5.0

20 30 40 50 60

% Wood Filler

Fle

xu

ral M

OE

(G

Pa

)

1.1

1.251.27 1.27

1

1.05

1.1

1.15

1.2

1.25

1.3

Wood Flour(AWF - 4020)

Talc CalciumCarbonate

Fiberglass

Fillers

We

igh

t

Wood Filled PP Products

Wood Filled PP Products

Wood Filled PP Products

Foaming Expands Possibilities For Wood Fibre / PP Composites

Foaming Expands Possibilities For Wood Fibre / PP Composites

Breakthrough Technology“Plastic Steel from Wood Filled PP”

• Expanded Oriented Wood filled PP• Low temperature die drawing • Synthetic Hardwood Technologies USA• Automotive side beams• Wood look – alike

Product Flexural Modulus ( M Pa )

PP 1800 EOW PP 7585

‘Plastics Steel’ Die Drawing Makes From Wood Filled PP

Material Flexural Strength Flexural Modulus

(MPa)

PP 48 1860

Wood 96 8946

O-PP 276 7585

EOW-PP 138 7585

Ram extrusion of PP / wood filled creates light weight wood-like material, even

stronger than wood

Wood Fibre Adds Stiffness & Value To Tight Tolerance Tubes

Polypropylene Developments

Wood Filled Repol PPfor Door Trims

PVC / Wood Composites

Outlook For The Future

• USA: 50 % growth rate of WPCs for building products

• ASTM Standards for building products based on WPCs

• Automotive : 15 % growth rate

Innovation in processing & product performance

Summary

The future of wood plastic composites will ultimately

depend on many factors; including new product

identification, product quality, consumer perception

& performance of these materials !