Change of the properties of plywood during the thermomodification of veneer and the polarization of the glue

Bonding performance of Chinese fir heartwood and sapwood with different coatings under a high voltage electric field

“…The ndings demonstrated a signi cant decrease in the viscosity and wetting properties of urea-formaldehyde resin on the wood surface under the in uence of physical elds, resulting in a remarkable 196% increase in the bonding strength of the composite materials (Popov et al 2020). Zamilova et al (2017) conducted research showing that electric elds induce changes in the structure of the adhesive polymer matrix, leading to the formation of new molecular bonds through macromolecular crosslinking, thereby increasing plywood bonding strength by 135%. When subjected to high-voltage electric elds (> 1 kV), electron excitation in the excited state facilitates the aggregation of more active functional groups on the material surface, thereby promoting an increase in surface free energy.…”