The synergistic effect of microwave drying and plasma surface treatments on the wettability of green wood

Sinergistični učinek mikrovalovnega sušenja in obdelave s plazmo na omočljivost svežega lesa


  • Sauradipta Ganguly
  • Jure Žigon
  • Kavyashree Srinivasa
  • Marko Petrič
  • Sebastian Dahle



Norway spruce wood, Wood drying, Microwave processing, Gliding arc plasma


In spite of being both a one-step solution to several problems associated with woodworking and also energy efficient, the application of microwave (MW) modification in wood research has remained very limited and this promising method has practically no use in wood industries across the globe. Research done so far in this field primarily sheds light on its potential in enhancing wood permeability, treatability and uniform wood drying. While MW treatments are mostly used on wet or green wood, another modification technique, plasma, has potential benefits to synergistically enhance the effects of MW treatment, but so far has not been applied on wet or green wood specimens. This study takes a first step to investigate the effects of plasma treatments (PT) on green wood specimens, as well as combinations of MW and plasma treatments. As a preliminary study, the methodology focuses on water contact angle measurements, since these are most commonly used as indicators for surface modifications in industrial applications. An exponential time dependence was found for the contact angle on the investigated samples of Norway spruce (Picea abies Karst.). Initial contact angles after droplet deposition increased due to drying and migration of organic molecules during treatments. In comparison with the literature, the effect of plasma was significantly less pronounced on wet wood specimens. The initial contact angles showed the lowest statistical variations after MW treatment, whereas plasma increased inhomogeneities. The final contact angles on treated specimens was lowest for PT-only specimens as well as specimens treated with plasma after MW. In contrast to the initial contact angles, the final contact angles showed the lowest variations after PT. Wetting rates were insignificantly improved by plasma, with reduced statistical variations after all treatments.


Download data is not yet available.


Avramidis, G., Wascher, R., Militz, H., & Viöl, W. (2016). Impact of air-plasma treatment at atmospheric pressure on wood and wood extractives. International Wood Products Journal, 7 (2), 76-79. DOI:

Awoyemi, L. (2004). Effects of microwave modification on the kiln drying time of Eucalyptus obliqua wood. Journal of Indian Academy of Wood Science, 1, 83-88.

Balboni, B. M., Ozarska, B., Garcia, J. N., & Torgovnikov, G. (2018). Microwave treatment of Eucalyptus macrorhyncha timber for reducing drying defects and its impact on physical and mechanical wood. European Journal of Wood and Wood Products, 76, 861–870. DOI:

Bartoli, M., Frediani, M., Briens, C., Berruti, F., & Rosi, L. (2019). An overview of temperature issues in microwave-assisted pyrolysis. Processes, 7 (10), 658. DOI:

Boehme, C., & Hora, G. (1996). Water absorption and contact angle measurement of native European, North American and tropical wood species to predict gluing properties. Holzforschung, 50 (3), 269-276. DOI:

Brodie, G. (2010). Wood: Microwave modification of properties. Encycl. Agric. Food Biol. Eng., 2010, 1878–1881.

Dahle, S., Žigon, J., Petrič, M., & Kariž, M. (2020a). Plasma treatment of spruce wood changes its dielectric properties. Les/Wood, 69 (2), 83-95. DOI:

Dahle, S., Žigon, J., Gospodarič, B., Zaplotnik, R., Merhar, M., & Petrič, M. (2020b). Open-source integrated plasma treatment and CNC machining system. Zenodo. DOI:

Dahle, S., Ganguly, S., Žigon, J., Srinivasa, K., & Petrič, M. (2021). Raw and analyzed data for the manuscript "The synergistic effect of microwave drying and plasma surface treatments on the wettability of green wood". (1.0.0) [Data set]. Zenodo. DOI:

ISO standard EN 13183-1:2002 Moisture content of a piece of sawn timber - Part 1: Determination by oven dry method.

Ganguly, S., Hom, S. K., Tripathi, S., Ghosh, S., Kanyal, R., & Samani, A. (2021a). Quantitative evaluation of microwave irradiation on short-rotation plantation wood species. Maderas Ciencia y Tecnologia, 23, 1–14.

Ganguly, S., Balzano, A., Petrič, M., Kržišnik, D., Tripathi, S., Žigon, J., & Merela, M. (2021b). Effects of different energy intensities of microwave treatment on heartwood and sapwood microstructures in Norway spruce. Forests, 2021 (12), 598. DOI:

Guanben, D., Siqun, W., & Zhiyong, C. (2005). Microwave drying of wood strands. Drying Technology, 23, 1–16.

Haase, J. G., Leung, L. H., & Evans, P. D. (2019). Plasma pre-treatments to improve the weather resistance of polyurethane coatings on black spruce wood. Coatings, 9 (1), 8. DOI:

Hämäläinen, K., & Kärki, T. (2013). Effects of atmospheric plasma treatment on the surface properties of wood-plastic composites. Advanced Materials Research, 718-720, 176-185. DOI:

He, S., Lin, L., Fu, F., Zhou, Y., & Fan, M. (2014). Microwave treatment for enhancing the liquid permeability of Chinese fir. BioResources, 9 (2), 1924-1938.

Hermoso, E., & Vega, A. (2016). Effect of microwave treatment on the impregnability and mechanical properties of eucalyptus globulus wood. Maderas Ciencia y Tecnologia, 18, 55–64.

Herron, J. T., & Green, D. S. (2001). Chemical kinetics database and predictive schemes for nonthermal humid air plasma chemistry. Part II. Neutral species reactions. Plasma Chemistry and Plasma Processing, 21, 459–481. DOI:

Hong-Hai, L., Qing-Wen, W., Lin, Y., Tao J., & Ying-Chun, C. (2005). Modification of larch wood by intensive microwave irradiation. Journal of Forestry Research, 16, 237–240. DOI:

Kalnins, M., Katzenberger, C., Schmieding, S., & Brooks, J. (1988). Contact angle measurement on wood using videotape technique. Journal of Colloid and Interface Science, 125 (1), 344–346. DOI:

Klarhöfer, L., Viöl, W., & Maus-Friedrichs, W. (2010). Electron spectroscopy on plasma treated lignin and cellulose. Holzforschung, 64, 331-336. DOI:

Král, P., Ráhel, J., Stupavská, M., Šrajer, J., Klímek, P., Mishra, P. K., & Wimmer, R. (2015). XPS depth profile of plasma-activated surface of beech wood (Fagus sylvatica) and its impact on polyvinyl acetate tensile shear bond strength. Wood Science and Technology, 49, 319-330. DOI:

Krapež Tomec, D., Žigon, J., Kitek Kuzman, M., Dahle, S., Šernek, M., & Kariž, M. (2021). Effect of plasma treatment of 3D printed parts on bonding to wood with PVAc adhesive. Polymers, 13 (8), 1211. DOI:

Liu, H. H., Wang, Q. W., Yang, L., Jiang, T., & Cai, Y. C. (2005). Modification of larch wood by intensive microwave irradiation. Journal of Forestry Research, 16 (3), 237-240. DOI:

Mekhtiev, M. A., & Torgovnikov, G. (2004). Method of check analysis of microwave-modified wood. Wood Science and Technology, 38 (7), 507-519. DOI:

Melamies, I. A. (2014). Feeling the rush of speed - New impregnation process for race skis. JOT International Surface Technology, 3.2014, 32-35.

Oloyede, A., & Groombridge, P. (2000). The Influence of microwave heating on the mechanical properties of wood. Journal of Materials Processing Technology, 100, 67–73.

Ouertani, S., Hassini, L., Azzouz, S., Torres, S. S., Belghith, A., & Koubaa, A. (2015). Modeling of combined microwave and convective drying of wood: prediction of mechanical behavior via internal gas pressure. Drying Technology, 33, 1234-1242. DOI:

Papp, E. A., & Csiha, C. (2017). Contact angle as function of surface roughness of different wood species. Surfaces and Interfaces, 8, 54-59. DOI:

Prysiazhnyi, V., Zaporojchen, V., Kersten, H., & Černák, M. (2012). Influence of humidity on atmospheric pressure air plasma treatment of aluminium surfaces. Applied Surface Science, 258 (14), 5467-5471. DOI:

Rehn, P., Wolkenhauer, A., Bente, M., Förster, S., & Viöl, W. (2003). Wood surface modification in dielectric barrier discharges at atmospheric pressure. Surface and Coatings Technology, 174–175, 515-518. DOI:

Riedl, B., Angel, C., Prégent, J., Blanchet, P., & Stafford, L. (2014). Effect of wood surface modification by atmospheric-pressure plasma on waterborne coating adhesion. Bioresources, 9 (3), 4908-4923.

Sakiyama, Y., Graves, D. B., Chang, H.-W., Shimizu, T., & Morfill, G. E. (2012). Plasma chemistry model of surface microdischarge in humid air and dynamics of reactive neutral species. Journal of Physics D: Applied Physics, 45 (42), 425201. DOI:

Samani, A., Ganguly, S., Kanyal, R., & Tripathi, S. (2019). Effect of microwave pre-treatment on preservative retention and treatability of Melia composita wood. Journal of Forest Science, 65, 391–396.

Sethy, A. K., Torgovnikov, G., Vinden, P., & Przewloka, S. (2016). Moisture conditioning of wood using a continuous microwave dryer. Drying Technology, 34, 318–323.

Šernek, M. (2002). Influence of drying temperature on properties of wood surfaces. Zbornik gozdarstva in lesarstva, 67, 173-191.

Terziev, N., Daniel, G., Torgovnikov, G., & Vinden, P. (2020). Effect of microwave treatment on the wood structure of Norway spruce and radiata pine. Bioresources, 15 (3), 5616-5626. DOI:

Torgovnikov, G., & Vinden, P. (2009). High-intensity microwave wood modification for increasing permeability. Forest Products Journal, 59, 84–92.

Torgovnikov, G., & Vinden, P. (2010). Microwave wood modification technology and its applications. Forest Products Journal, 60, 173–182.

Treu, A., Rieche, H., & Militz, H. (2008). Spruce and pine heartwood treatment by means of microwave radiation. In: Proceedings of the 39th Annual Meeting the International Research Group on Wood Protection, 2008.

Wascher, R., Avramidis, G., & Viöl, W. (2021). Plywood made from plasma-treated veneers: investigation of performance differences between plasma-pretreated and untreated beech veneers at comparable melamine resin load. Forests, 12 (10), 1423. DOI:

Weng, X., Zhou, Y., Fu, Z., Gao, X., Zhou, F., & Jiang, J. (2021). Effects of microwave pretreatment on drying of 50 mm-thickness Chinese fir lumber. Journal of Wood Science, 67, 1–9.

Weng, X., Zhou, Y., Fu, Z., Gao, X., Zhou, F., & Fu, F. (2020). Effects of microwave treatment on microstructure of Chinese fir. Forests, 11, 772. DOI:

Žigon, J., Petrič, M., & Dahle, S. (2018). Dielectric barrier discharge (DBD) plasma pretreatment of lignocellulosic materials in air at atmospheric pressure for their improved wettability: A literature review. Holzforschung, 72 (11), 979-991. DOI:

Žigon, J., Pavlič, M., Kibleur, P., van den Bulcke, J., Petrič, M., van Acker, J., & Dahle, S. (2020a). Treatment of wood with atmospheric plasma discharge: study of the treatment process, dynamic wettability and interactions with a waterborne coating. Holzforschung, 75 (7), 603-613. DOI:

Žigon, J., Kovač, J., Zaplotnik, R., Saražin, J., Šernek, M., Petrič, M., & Dahle S. (2020b). Enhancement of strength of adhesive bond between wood and metal using atmospheric plasma treatment. Cellulose, 27, 6411-6424. DOI:







How to Cite

Ganguly, S., Žigon, J., Srinivasa, K., Petrič, M., & Dahle, S. (2022). The synergistic effect of microwave drying and plasma surface treatments on the wettability of green wood: Sinergistični učinek mikrovalovnega sušenja in obdelave s plazmo na omočljivost svežega lesa. Les/Wood, 71(1), 5-14.

Similar Articles

1-10 of 114

You may also start an advanced similarity search for this article.

Most read articles by the same author(s)

1 2 > >>