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Flax Fiber as Reinforcement in Recycled Tire Rubber and Thermoplastics Composite

Jimmy Fung and Satya PanigrahiAgricultural & Bioresource Engineering Dept.

University of Saskatchewan

CSBE/SCGAB 2008 Annual ConferenceVancouver, British Columbia

July 13 - 16, 2008

Paper No. CSBE08-191

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Outline

Introduction Objectives Materials Experimental Method Results & Discussions Conclusion

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Introduction

Natural fibers have been used as the reinforcement in plastic industry

Advantages with natural fiber: lower density, lower processing temperature, non-abrasive nature, renewable and relatively cheaper in cost

Scrap rubber: non-degradable, e.g. wasted carpet rubber underlay, industrial wasted rubber and wasted tires

Serious solid waste disposal and hazard environmental problem

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Introduction (con’t)

Developing new and innovative materials utilizing agricultural residue and recycled polymer Reduction of CO2

Add crop’s economic value Recycling

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Objectives

Investigate a viable biocomposite material from the flax fiber/shive, recycled tire rubber and thermoplastics

Develop the extrusion and compression molding process on this composite material

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MaterialsSaskatchewan-grown oilseed flax fiber Contains 80% fiber, 20% shives Without any treatment Thermal degradation temperature:

Cellulose: 300ºC Hemicellulose: 220 to 280ºC Lignin: 280 to 300ºC

Oilseed Flax FieldRetted Flax Bale

Decorticated Flax Fiber

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Materials (con’t)

Recycled ground tire rubber (GTR) Size about 0.4 mm, density 1226 kg/m3

Linear Low Density Polyethylene (LLDPE) Melting temperature is at 127 oC; and crystallization

temperature is 112.7 oC

Lubricant Improve the process smoothness

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Experimental Method

A 50 50 100B 60 40 100

Mixture Code

Ground Tire Rubber

LLDPE Total

Composition (% in weight)

1 A 90 0 102 A 85 5 103 A 80 10 104 A 75 15 105 B 90 0 106 B 85 5 107 B 80 10 108 B 75 15 10

Composition (% in weight)Sample Code

Mixture Code

Mixture Flax Wax

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Composite Preparation

Flax fiber – size used through 2 mm screen Mix the materials in different composition ratio Blend the mixture with mixer

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Processing ProcedureExtrusion

Single-screw extruder Cross-linked rubber can be broken

under high shear stress and high temperature

Fiber mixed into the polymer Max temperature used: 200°C

Compression Molding Heated press into 20 cm x 20 cm

square shape sample Heating temperature: 150°C

Extruder

Heated press

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Material & Properties Tests

Tearing test : ASTM D624-00 Tensile test : ASTM D412-98a Water absorption test: ASTM D570-98 Durometer hardness test : ASTM D2240-02b

Type C tearing test specimen

Dumbbell tensile test specimens

Instron testing machine

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Results & Discussions

Tearing test results of the biocomposites

GTR:LLDPE

8765 41 2 30

10

20

30

40

Flax Fiber Content (% w/w)

Me

an

of

Ma

x T

ea

r S

tre

ng

ht

(kN

/m)

60:40

50:50

60:40 23.523 22.905 22.871 22.538

50:50 32.876 31.143 32.300 28.404

0 5 10 15

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Results & Discussions (con’t)

GTR:LLDPE

5 6 7 81 2 3 40.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

Flax Fiber Content (% w/w)

Me

an

of

Te

ns

ile Y

ield

Str

es

s

(MP

a)

60:40

50:50

60:40 1.68 2.08 2.49 2.33

50:50 2.90 3.08 2.98 3.14

0 5 10 15

Tensile test results (in yield stress) of the biocomposites

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Results & Discussions (con’t)

GTR:LLDPE

8765 1 2 3 40

100

200

300

400

Flax Fiber Content (% w/w)

Me

an

of

Yo

un

g's

Mo

du

lus

(M

Pa

) 60:40

50:50

60:40 116.9 138.1 194.1 214.5

50:50 136.2 205.8 224.4 332.9

0 5 10 15

Tensile test results (in Young’s modulus) of the biocomposites

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Results & Discussions (con’t)

Water Absorption test results of the biocomposites

GTR:LLDPE

5

6 7 8

1

4320.0

0.5

1.0

1.5

2.0

2.5

3.0

Fiber Content (% w/w)

Mea

n o

f In

crea

se i

n W

eig

ht

(%

w/w

)

60:40

50:50

60:40 0.25 0.59 1.07 1.74

50:50 0.25 0.51 0.88 2.50

0 5 10 15

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Results & Discussions (con’t)

GTR:LLDPE

65 7 8 43210

10

20

30

40

50

Flax Fiber Content (% w/w)

Me

an

of

Sh

ore

Du

rom

ete

r R

ea

din

g

60:40

50:50

60:40 37.3 40.5 41.2 35.7

50:50 41.6 40.2 42.7 43.6

0 5 10 15

Hardness test results of the biocomposites

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Conclusion Composite can be done through the extrusion and

compression molding processes

Flax fiber has been successfully demonstrated as the reinforcement in the biocomposite

Tensile yield strength and stiffness of GTR - LLDPE composite are improved with adding flax fiber content

Higher LLDPE content exhibited higher tensile strength, better stiffness, improved tear strength, less water absorption and harder

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Acknowledgements

Saskatchewan Agriculture Research Chair Program in Engineering.

NSERC Biofibre Industries Ltd. SaskBet Inc Department of Agriculture and Bioresource

Engineering at the University of Saskatchewan

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References

Fukumori, K. and M. Matsushita. 2003. Material Recycling Technology of Crosslinked Rubber Waste – Review. R&D Review of Toyota CRDL. Vol. 38 No. 1. Science Links Japan. Available at: http://sciencelinks.jp/j-east/journal/R/ G0820B/ 2003.php (Accessed 29 September 2007)

Mohanty, A.K., M. Misra and L.T. Drzal. 2001. Surface modifications of natural fibers and performance of the resulting biocomposites: An overview. Composite Interfaces. Vol. 8: 313-343.

Saheb, N.D. and J.P. Jog. 1999. Natural fiber polymer composites: A review. In Advance in Polymer Technology. Vol. 18, No. 4, 351-363.

Van de Velde, K. and P. Kiekens. 2002. Thermal degradation of flax: the determination of kinetic parameters with thermogravimetric analysis. Journal of Applied Polymer Science. Vol. 3: 2634-2643.

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Thank You

Questions?