Skip to main content
Log in

Application of micromechanical models to tensile properties of wood–plastic composites

  • Original
  • Published:
Wood Science and Technology Aims and scope Submit manuscript


Wood–plastic composites (WPC) were produced with white birch pulp fibers of different aspect ratios (length-to-diameter), high-density polyethylene, and using two common processes: extrusion or injection molding. Three additive levels were also used: no additive, compatibility agent, and process lubricant. Fiber size was measured with an optical fiber quality analyzer. Tensile properties of WPC were measured and modeled as a function of fiber aspect ratio. Models were fitted to experimental values using the minimum sum of squared error method. A shift from the oriented fiber case (injection molding) to the randomly oriented fiber case (extrusion) was achieved using a fiber orientation factor. Fiber/matrix stress transfer increased with increasing fiber aspect ratio. Stress transfer was reduced with the use of process lubricant. Unexpectedly, the compatibility agent had the same effect. Fiber strength and stiffness contributions to the composite were lower than those of intrinsic fiber properties.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5

Similar content being viewed by others


  • Baïlon JP, Dorlot JM (2000) Des matériaux, troisième édition. Presses Internationales Polytechnique, Montréal

  • Beckermann GW, Pickering KL (2009) Engineering and evaluation of hemp fibre reinforced polypropylene composites: micro-mechanics and strength prediction modelling. Composites Part A 40:210–217

    Article  Google Scholar 

  • Clemons C (2002) Wood-plastic composites in the United States-The interfacing of two industries. Forest Prod J 52(6):10–18

    Google Scholar 

  • Cox HL (1952) The elasticity and strength of paper and other fibrous materials. Br J Appl Phys 3:72–79

    Article  Google Scholar 

  • Doan TTL, Gao SL, Mäder E (2006) Jute/polypropylene composites I. Effect of matrix modification. Compos Sci Technol 66:952–963

    Article  CAS  Google Scholar 

  • Gibson RF (2007) Principles of composite material mechanics. CRC Press, New York

    Google Scholar 

  • Godara A, Raabe D, Bergmann I, Putz R, Müller U (2009) Influence of additives on the global mechanical behavior and the microscopic strain localization in wood reinforced polypropylene composites during tensile deformation investigated using digital image correlation. Compos Sci Technol 69:139–146

    Article  CAS  Google Scholar 

  • Halpin JC (1969) Stiffness and expansion estimates for oriented short fiber composites. J Compos Mater 3:732–734

    Google Scholar 

  • Herra-Franco PJ, Valadez-González A (2005) A study of the mechanical properties of short natural-fiber reinforced composites. Composites Part B 36:597–608

    Google Scholar 

  • Kalaprasad G, Joseph K, Thomas S, Pavithran C (1997) Theoretical modelling of tensile properties of short sisal fibre-reinforced low-density polyethylene composites. J Mater Sci 32:4261–4267

    Article  CAS  Google Scholar 

  • Kelly A (1973) Strong solids, vol 2. Clarendon Press, Oxford

    Google Scholar 

  • Li H, Law S, Sain M (2004) Process rheology and mechanical property correlationship of wood flour-polypropylene composites. J Reinf Plast Compos 23(11):1153–1158

    Article  CAS  Google Scholar 

  • Mark RE, Habeger CC, Borch J, Lyne BM, Murakami K (2002) Handbook of physical testing of paper, vol 1, 2nd edn. Marcel Dekker, New York

    Google Scholar 

  • Marklund E, Varna J, Neagu CR, Gamstedt KE (2008) Stiffness of aligned wood fiber composites: effect of microstructure and phase properties. J Compos Mater 42(22):2377–2405

    Article  Google Scholar 

  • Migneault S, Koubaa A, Erchiqui F, Chaala A, Englund K, Wolcott MP (2009) Effects of processing method and fiber size on the structure and properties of wood–plastic composites. Composites Part A 40:80–85

    Article  Google Scholar 

  • Neagu CR, Gamstedt KE, Berthold F (2006) Stiffness contribution of various wood fibers to composite materials. J Compos Mater 40(8):663–698

    Article  CAS  Google Scholar 

  • TAPPI (1996) Zero–span breaking strength of pulp (dry zero–span tensile). Standard T 231 cm–96. Technical association of the pulp and paper industry, Atlanta

    Google Scholar 

  • Rowell RM (2007) Challenges in biomass–thermoplastic composites. J Polym Environ 15:229–235

    Article  CAS  Google Scholar 

  • Simonsen J (1997) Efficiency of reinforcing materials in filled polymer composites. Forest Prod J 47(1):74–81

    CAS  Google Scholar 

  • Smith PM, Wolcott MP (2006) Opportunities for wood/natural fiber–plastic composites in residential and industrial applications. Forest Prod J 56(3):4–11

    Google Scholar 

  • Smook GA (2002) Handbook for pulp & paper technologists, 3rd edn. Angus Wilde publications, Vancouver

    Google Scholar 

  • Sretenovic A, Müller U, Gindl W (2006) Mechanism of stress transfer in a single wood fibre–LDPE composite by means of electronic laser speckle interferometry. Composites Part A 37(9):1406–1412

    Article  Google Scholar 

Download references


The authors are grateful to the Canada Research Chair Program, the Ministère du développement économique et de l’innovation et de l’Exportation (MDEIE) du Québec, NSERC, Caisse Populaire Desjardins, Tembec, and the UQAT Foundation for financial support. The authors wish to thank Professor Michael Wolcott and Dr. Karl Englund from Washington State University for granting access to the Wood Engineering Material Laboratory and for their collaboration on this project.

Author information

Authors and Affiliations


Corresponding author

Correspondence to Ahmed Koubaa.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Migneault, S., Koubaa, A., Erchiqui, F. et al. Application of micromechanical models to tensile properties of wood–plastic composites. Wood Sci Technol 45, 521–532 (2011).

Download citation

  • Received:

  • Published:

  • Issue Date:

  • DOI: