Wood modification with glyoxal resins such as 1.3-dimethylol-4.5-dihydroxyethyleneurea (DMDHEU) has been studied extensively since the early 2000s (Emmerich et al. 2019). Originally developed for textile finishing, reactions of DMDHEU monomers in cellulose-based fabrics are cross-linking of cellulose molecules and self-condensation of DMDHEU via the reactive hydroxymethyl groups (Schindler and Hauser 2004). The same reaction types of the resin may be expected when utilizing DMDHEU in wood modification processes. However, recent results indicate that a reduction in maximum swelling is nearly entirely based on cell wall bulking, without a significant reduction in the water-saturated sample dimensions that would indicate a cross-linking effect (Krause et al. 2003). In this study, we used DMDHEU and methylolated DMDHEU molecules to analyze how cell wall bulking and cross-linking affect the water vapor sorption behavior and the hydroxyl accessibility of the modified wood.
Keywords: glyoxal resins, cell wall bulking, hydroxyl accessibility
Authors
Lukas Emmerich
University of Goettingen, WB and WP, Göttingen, Germany
Michael Altgen
Lauri Rautkari
Holger Militz
Login to download the PDF