Wood Science and Technology

, Volume 45, Issue 3, pp 521–532 | Cite as

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

  • Sébastien Migneault
  • Ahmed KoubaaEmail author
  • Fouad Erchiqui
  • Abdelkader Chaala
  • Karl Englund
  • Michael P. Wolcott


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.


Injection Molding Fiber Orientation HDPE Tensile Modulus Interfacial Shear Stress 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



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.


  1. Baïlon JP, Dorlot JM (2000) Des matériaux, troisième édition. Presses Internationales Polytechnique, MontréalGoogle Scholar
  2. Beckermann GW, Pickering KL (2009) Engineering and evaluation of hemp fibre reinforced polypropylene composites: micro-mechanics and strength prediction modelling. Composites Part A 40:210–217CrossRefGoogle Scholar
  3. Clemons C (2002) Wood-plastic composites in the United States-The interfacing of two industries. Forest Prod J 52(6):10–18Google Scholar
  4. Cox HL (1952) The elasticity and strength of paper and other fibrous materials. Br J Appl Phys 3:72–79CrossRefGoogle Scholar
  5. Doan TTL, Gao SL, Mäder E (2006) Jute/polypropylene composites I. Effect of matrix modification. Compos Sci Technol 66:952–963CrossRefGoogle Scholar
  6. Gibson RF (2007) Principles of composite material mechanics. CRC Press, New YorkGoogle Scholar
  7. 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 69:139–146CrossRefGoogle Scholar
  8. Halpin JC (1969) Stiffness and expansion estimates for oriented short fiber composites. J Compos Mater 3:732–734Google Scholar
  9. Herra-Franco PJ, Valadez-González A (2005) A study of the mechanical properties of short natural-fiber reinforced composites. Composites Part B 36:597–608Google Scholar
  10. 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 32:4261–4267CrossRefGoogle Scholar
  11. Kelly A (1973) Strong solids, vol 2. Clarendon Press, OxfordGoogle Scholar
  12. Li H, Law S, Sain M (2004) Process rheology and mechanical property correlationship of wood flour-polypropylene composites. J Reinf Plast Compos 23(11):1153–1158CrossRefGoogle Scholar
  13. Mark RE, Habeger CC, Borch J, Lyne BM, Murakami K (2002) Handbook of physical testing of paper, vol 1, 2nd edn. Marcel Dekker, New YorkGoogle Scholar
  14. 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):2377–2405CrossRefGoogle Scholar
  15. 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 40:80–85CrossRefGoogle Scholar
  16. Neagu CR, Gamstedt KE, Berthold F (2006) Stiffness contribution of various wood fibers to composite materials. J Compos Mater 40(8):663–698CrossRefGoogle Scholar
  17. 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, AtlantaGoogle Scholar
  18. Rowell RM (2007) Challenges in biomass–thermoplastic composites. J Polym Environ 15:229–235CrossRefGoogle Scholar
  19. Simonsen J (1997) Efficiency of reinforcing materials in filled polymer composites. Forest Prod J 47(1):74–81Google Scholar
  20. Smith PM, Wolcott MP (2006) Opportunities for wood/natural fiber–plastic composites in residential and industrial applications. Forest Prod J 56(3):4–11Google Scholar
  21. Smook GA (2002) Handbook for pulp & paper technologists, 3rd edn. Angus Wilde publications, VancouverGoogle Scholar
  22. 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):1406–1412CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Sébastien Migneault
    • 1
  • Ahmed Koubaa
    • 2
    Email author
  • Fouad Erchiqui
    • 2
  • Abdelkader Chaala
    • 3
  • Karl Englund
    • 4
  • Michael P. Wolcott
    • 4
  1. 1.Centre de recherche sur le boisUniversité LavalQuébecCanada
  2. 2.Université du Québec en Abitibi–TémiscamingueRouyn–NorandaCanada
  3. 3.Service de recherche et d’expertise en transformation des produits forestiersAmquiCanada
  4. 4.Wood Materials and Engineering LaboratoryWashington State UniversityPullmanUSA

Personalised recommendations