European Journal of Wood and Wood Products

, Volume 76, Issue 2, pp 549–562 | Cite as

Effect of short-term thermomechanical densification of wood veneers on the properties of birch plywood

  • Pavlo BekhtaEmail author
  • Ján Sedliačik
  • Dennis Jones


In this study, the physical and mechanical properties of plywood panels made from pre-compressed birch (Betula verrucosa Ehrh.) veneer were evaluated. Veneer sheets underwent short-term thermo-mechanical (STTM) compression at temperatures of 150 or 180 °C and at pressures of 0.5, 1.0, 1.5, 2.0, 2.5, 3.0 or 3.5 MPa for a period of 1 min prior to adhesive being applied and pressed into panels using phenol formaldehyde adhesive at 100 g/m2 spread rate; this was one-third less than the adhesive spread used for the control panels (150 g/m2). The pressing pressure was 1.0 MPa, which was almost half of the pressure used for the control panels (1.8 MPa); and pressing time was 3 min, also half of the pressing time used for the control panels (6 min). The results showed that surface roughness of compressed veneer, water absorption and thickness swelling of plywood panels made from compressed veneer were significantly improved. The shear strength values of plywood panels made from compressed birch veneer even with reduced adhesive spread were higher than those of plywood panels made from uncompressed veneer. The findings in this study indicated that compression of birch veneer could be considered as an alternative to produce more eco-friendly (owing to smaller adhesive spread) value-added material with enhanced properties.



The authors acknowledge COST Action FP1303 “Performance of bio-based building materials” for support of STSM-FP1303-010615-060045. This work was supported by the Slovak Research and Development Agency under the contract no APVV-14-0506 and APVV-15-0235. Special thanks are extended to Ing. B. Lizoň for making microscopic images of veneer samples surfaces before and after densification.


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Copyright information

© Springer-Verlag GmbH Germany 2017

Authors and Affiliations

  1. 1.Department of Wood-Based CompositesCellulose and Paper, Ukrainian National Forestry UniversityLvivUkraine
  2. 2.Department of Furniture and Wood ProductsTechnical University in ZvolenZvolenSlovakia
  3. 3.SP Technical Research Institute of SwedenStockholmSweden

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