Abstract
Wetting of soy protein adhesives modified by urea on wood surfaces was investigated with sessile liquid droplet method. Dynamic contact angles were used to illustrate the wetting process. The effects of wood surface roughness and urea concentration on contact angles were investigated. Moreover, two wetting models were used to describe the dynamic contact angle process, in which the contact angle change rate constant (K) can be used to quantify the adhesive spreading and penetration during the wetting process. The results showed that the wetting models could accurately describe the dynamic wetting process of soy protein adhesives on wood surfaces.
Zusammenfassung
Der Auftrag von mit Harnstoff modifiziertem Sojaproteinklebstoff auf Holzoberflächen wurde mit dem Verfahren des „ruhenden Tropfens“ (Sessile-Drop-Verfahren) untersucht. Der Benetzungsverlauf wurde mittels dynamischer Kontaktwinkelmessung aufgezeigt. Die Einflüsse der Oberflächenrauhigkeit des Holzes sowie der Harnstoffkonzentration auf die Kontaktwinkel wurden untersucht. Anhand zweier Benetzungsmodelle wurde der dynamische Kontaktwinkelverlauf beschrieben, wobei die Konstante (K) der Funktion der Kontaktwinkeländerung zur Bestimmung der Klebstoffverteilung und der Eindringung in das Holz während der Benetzung verwendet wird. Die Ergebnisse zeigten, dass mit den Benetzungsmodellen der dynamische Benetzungsprozess von Sojaproteinklebstoff auf Holzoberflächen zutreffend dargestellt werden kann.
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The study was financed by the International Cooperation Fund from Zhejiang Science and Technology Department (No. 2010C34007).
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Xu, HN., Shen, QY., Ouyang, XK. et al. Wetting of soy protein adhesives modified by urea on wood surfaces. Eur. J. Wood Prod. 70, 11–16 (2012). https://doi.org/10.1007/s00107-010-0502-2
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DOI: https://doi.org/10.1007/s00107-010-0502-2