Wood Science and Technology

, Volume 53, Issue 2, pp 425–445 | Cite as

Mechanical behaviour of chemically modified Norway spruce (Picea abies L. Karst.): Experimental mechanical studies on spruce wood after methacrylation and in situ polymerization of styrene

  • Samuel Oluyinka Olaniran
  • Benjamin Michen
  • Diego F. Mora Mendez
  • Falk K. Wittel
  • Erik Valentine Bachtiar
  • Ingo Burgert
  • Markus RüggebergEmail author


Chemical modification of wood mainly aims at improving dimensional stability, resistance to biodeterioration and surface degradation. In some cases, it is specifically targeted at adapting or improving mechanical performance. However, a general understanding of the effects of chemical modification on the mechanical properties of wood, which would facilitate more efficient modification strategies, is missing. Here, a combined experimental and simulation study is provided to gain a more general understanding of the mechanical behaviour of chemically modified wood. In the first part of this study, the mechanical properties of chemically modified Norway spruce are studied experimentally. In Mora Mendez et al. (Wood Sci Technol 2019), simulations of different types of chemical modifications will be presented using a multi-scale model and the outcome will be compared with the obtained experimental data. Chemical modification was based on a two-step modification process. The first step involved methacrylation of the OH-groups in the cell wall. In the second step, in situ polymerization of styrene was induced in the methacrylated samples, which resulted in a partial cell wall and lumen filling. Tensile stiffness and rolling shear stiffness were analysed for methacrylated and polymerized samples. Whereas only small changes in mechanical properties were found for methacrylated samples, the polymerization process led to pronounced increases in elastic modulus and shear stiffness because of weight percent gains of 60–95%. Yet, the specific stiffness was lowered, as the density increase was disproportionate to the stiffness increase. Moreover, a pronounced improvement in rolling shear modulus (GRT) by a factor of 4.5 was obtained for the in situ polymerized specimen.



SOO acknowledges the financial support provided by the Federal Commission for Scholarships for Foreign Students with the award of Swiss Government Excellence Scholarship for doctoral research (ESKAS2015.0612). IB, DM and FW acknowledge the Swiss National Science Foundation for financial support in the framework of NRP 66 Project: Improved wood materials for structures and interior applications (NRP 66, Project No. 406640_139986). We also thank Thomas Schnider, Tobias Keplinger, Huizhang Guo and Merve Özparpucu for support and valuable discussions.


  1. Akitsu H, Norimoto M, Morooka T, Rowell RM (1993) Effect of humidity on vibrational properties of chemically modified wood. Wood Fiber Sci 25:250–260Google Scholar
  2. Alma M, Hafizo lu H, Maldas D (1996) Dimensional stability of several wood species treated with vinyl monomers and polyethylene glycol-1000. Int J Polym Mater 32:93–99CrossRefGoogle Scholar
  3. Arcan M, Hashin Z, Voloshin A (1978) A method to produce uniform plane-stress states with applications to fiber-reinforced materials. Exp Mech 18:141–146CrossRefGoogle Scholar
  4. Bachtiar EV, Sanabria SJ, Mittig JP, Niemz P (2017) Moisture-dependent elastic characteristics of walnut and cherry wood by means of mechanical and ultrasonic test incorporating three different ultrasound data evaluation techniques. Wood Sci Technol 51:47–67CrossRefGoogle Scholar
  5. Bengtsson C (2001) Variation of moisture induced movements in Norway spruce (Picea abies). Ann For Sci 58:568–581CrossRefGoogle Scholar
  6. Blaber J, Adair B, Antoniou A (2015) Ncorr: open-source 2D digital image correlation Matlab software. Exp Mech 55:1105–1122CrossRefGoogle Scholar
  7. Bucur V (2006) Acoustics of wood. Springer series in wood science. Springer, BerlinGoogle Scholar
  8. Burgert I, Frühmann K, Keckes J, Fratzl P, Stanzl-Tschegg SE (2003) Microtensile testing of wood fibers combined with video extensometry for efficient strain detection. Holzforschung 57:661–664CrossRefGoogle Scholar
  9. Clausen CA (2012) Enhancing durability of wood-based composites with nanotechnology. General technical report FPL–GTR-218:8-12Google Scholar
  10. Dahl KB, Malo K (2009) Linear shear properties of spruce softwood. Wood Sci Technol 43:499–525CrossRefGoogle Scholar
  11. Devi RR, Ali I, Maji T (2003) Chemical modification of rubber wood with styrene in combination with a crosslinker: effect on dimensional stability and strength property. Bioresour Technol 88:185–188CrossRefGoogle Scholar
  12. Dinwoodie J (1981) Timber, its nature and behaviour. Van Nostrand Reinhold Co 190:60–61Google Scholar
  13. EN 12668-1 (2010) Non-destructive testing—characterization and verification of ultrasonic examination equipment—part 1: instruments. CEN European Committee for StandardizationGoogle Scholar
  14. Epmeier H, Kliger R (2005) Experimental study of material properties of modified Scots pine. Holz als Roh-und Werkstoff 63:430–436CrossRefGoogle Scholar
  15. Esteves B, Nunes L, Pereira H (2011) Properties of furfurylated wood (Pinus pinaster). Eur J Wood Wood Prod 69:521–525CrossRefGoogle Scholar
  16. Gérardin P (2016) New alternatives for wood preservation based on thermal and chemical modification of wood—a review. Ann For Sci 73:559–570CrossRefGoogle Scholar
  17. Gonçalves R, Trinca AJ, Cerri DGP (2011) Comparison of elastic constants of wood determined by ultrasonic wave propagation and static compression testing. Wood Fiber Sci 43:64–75Google Scholar
  18. Hansmann C, Deka M, Wimmer R, Gindl W (2006) Artificial weathering of wood surfaces modified by melamine formaldehyde resins. Holz als Roh-und werkstoff 64:198CrossRefGoogle Scholar
  19. Hillis W (1984) High temperature and chemical effects on wood stability. Wood Sci Technol 18:281–293CrossRefGoogle Scholar
  20. Homan WJ, Jorissen AJ (2004) Wood modification developments. Heron 49:360–369Google Scholar
  21. Imamura H (1989) Contribution of extractives to wood characteristics. In: Natural products of woody plants. Springer, pp 843–860Google Scholar
  22. Keplinger T, Cabane E, Chanana M, Hass P, Merk V, Gierlinger N, Burgert I (2015) A versatile strategy for grafting polymers to wood cell walls. Acta Biomater 11:256–263CrossRefGoogle Scholar
  23. Keunecke D, Sonderegger W, Pereteanu K, Lüthi T, Niemz P (2007) Determination of Young’s and shear moduli of common yew and Norway spruce by means of ultrasonic waves. Wood Sci Technol 41:309CrossRefGoogle Scholar
  24. Kim J-W, Harper DP, Taylor AM (2009) Effect of extractives on water sorption and durability of wood-plastic composites. Wood Fiber Sci 41:279–290Google Scholar
  25. Kohlhauser C, Hellmich C (2013) Ultrasonic contact pulse transmission for elastic wave velocity and stiffness determination: influence of specimen geometry and porosity. Eng Struct 47:115–133CrossRefGoogle Scholar
  26. Lande S, Eikenes M, Westin M, Schneider MH (2008) Furfurylation of wood: chemistry, properties, and commercialization. ACS Publications, New YorkGoogle Scholar
  27. Lubarsky G, Davidson M, Bradley R (2004) Elastic modulus, oxidation depth and adhesion force of surface modified polystyrene studied by AFM and XPS. Surf Sci 558:135–144CrossRefGoogle Scholar
  28. Militz H (1991) Improvements of stability and durability of Beechwood (Fagus sylvatica) by means of treatment with acetic anhydride. In: Proceedings of 22nd annual meeting international research group on wood preservation, working group 3. Preservatives and methods of treatment. Kyoto, Japan. Doc. no: IRG/WP/3645Google Scholar
  29. Militz H (1993) Treatment of timber with water soluble dimethylol resins to improve their dimensional stability and durability. Wood Sci Technol 27:347–355CrossRefGoogle Scholar
  30. Miyake K, Satomi N, Sasaki S (2006) Elastic modulus of polystyrene film from near surface to bulk measured by nanoindentation using atomic force microscopy. Appl Phys Lett 89:031925CrossRefGoogle Scholar
  31. Mora Mendez DF, Olaniran SO, Rüggeberg M, Burgert I, Hermann HJ, Wittel FK (2019) Mechanical behavior of chemically modified Norway spruce: a generic hierarchical model for wood modifications. Wood Sci Technol. Google Scholar
  32. Norimoto M, Gril J, Rowell RM (1992) Rheological properties of chemically modified wood: relationship between dimensional and creep stability. Wood Fiber Sci 24:25–35Google Scholar
  33. Ozyhar T, Hering S, Niemz P (2013) Moisture-dependent orthotropic tension-compression asymmetry of wood. Holzforschung 67:395–404Google Scholar
  34. Pugh TL, Heller W (1957) Density of polystyrene and polyvinyltoluene latex particles. J Colloid Sci 12:173–180CrossRefGoogle Scholar
  35. Rafsanjani A, Lanvermann C, Niemz P, Carmeliet J, Derome D (2013) Multiscale analysis of free swelling of Norway spruce. Compos A Appl Sci Manuf 54:70–78CrossRefGoogle Scholar
  36. Ramage MH et al (2017) The wood from the trees: the use of timber in construction. Renew Sustain Energy Rev 68:333–359CrossRefGoogle Scholar
  37. Rowell RM (1983) Chemical modification of wood. Prod Abstr Rev Artic 6:362–382Google Scholar
  38. Rowell RM (1996) Physical and mechanical properties of chemically modified wood. Chem Modif Lignocellul Mater 1:295–310Google Scholar
  39. Singleton R, DeBell DS, Gartner BL (2007) Effect of extraction on wood density of western hemlock (Tsuga heterophylla (Raf.) Sarg.). Wood Fiber Sci 35:363–369Google Scholar
  40. Socrates G (2001) Infrared and Raman characteristic group frequencies: tables and charts. Wiley, HobokenGoogle Scholar
  41. Xie Y, Krause A, Militz H, Turkulin H, Richter K, Mai C (2007) Effect of treatments with 1,3-dimethylol-4,5-dihydroxy-ethyleneurea (DMDHEU) on the tensile properties of wood. Holzforschung 61:43–50CrossRefGoogle Scholar
  42. Xie Y, Fu Q, Wang Q, Xiao Z, Militz H (2013) Effects of chemical modification on the mechanical properties of wood. Eur J Wood Wood Prod 71:401–416CrossRefGoogle Scholar
  43. Yildiz ÜC, Yildiz S, Gezer ED (2005) Mechanical properties and decay resistance of wood–polymer composites prepared from fast growing species in Turkey. Bioresour Technol 96:1003–1011CrossRefGoogle Scholar
  44. Zaoui A (2002) Continuum micromechanics: survey. J Eng Mech 128:808–816CrossRefGoogle Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Institute for Building MaterialsETH ZurichZurichSwitzerland
  2. 2.Laboratory for Cellulose and Wood MaterialsEmpaDübendorfSwitzerland
  3. 3.Paul Scherrer InstituteVilligenSwitzerland

Personalised recommendations