Foaming the polyvinyl acetate (PVA) and poly urethane (PU) wood adhesive and characterization

Abstract

In this study, polyvinyl acetate (PVA) and polyurethane (PU) wood adhesives were foamed. It was aimed to achieve adhesive savings by allowing the adhesives to cover a larger surface area through foaming. Egg white (EW), wheat flour (WF), and Sodium Lauretha Sulfate (SLES) were used as foaming agents for the adhesives. The foaming agents were mechanically mixed within a glass container to foaming, and then adhesive was added to the foam and mixed again using a mechanical mixer. The characterization of the foamed adhesives was conducted through viscosity and perpendicular adhesive strength (PB)analyses according to TSE standards. According to the analysis results, it has been determined that foaming PU adhesive with foaming agents is more successful. The foam stability of PVA adhesive was significantly low, as the foam completely deflated after approximately 30 minutes. The addition of EW and WF to PU resulted in a more solid and rigid foam. Thanks to this characteristic, PU foams can be used in the production of wood sandwich panels. According to the study results, further research is anticipated to be conducted on the foaming of PU adhesive, and the obtained foams are predicted to be used in the furniture industry for panel production.