The effect of using Alkali sulfit-Anthraquinone (AS-AQ) liquor powder as filler of urea formaldehyde resin on functional properties of plywood

In this research, the use of alkali sulfite - anthraquinone liqueur powder as filler of urea formaldehyde resin and replacing with wheat flour in the production of plywood was considered. The AS-AQ liquor powder was used as filler of UF resin in plywood manufacture at four levels of 0, 5, 10 and 15% based on oven dry weight of UF resin. Then the physical and mechanical properties of the samples, including thickness swelling after 2 and 24 hours immersion in water, bending strength and modulus of elasticity (parallel and perpendicular to surface grain) and bonding shear strength were measured. The results showed that the amount of thickness swelling of the boards after 2 and 24 hours of immersion in water did not increase significantly, and all the levels had a thickness swelling at the standard level. Increasing the consumption of liqueur powder did not have a negative significant effect on the dimensional stability of the boards. Bending strength and modulus of elasticity parallel and perpendicular to the surface layer fiber was improved by an increase in the use of liquor powder, but there was no significant difference between the difference levels. Therefore considering the physical and mechanical properties of the boards, it is appropriate to use alkali sulfite - anthraquinone (AS-AQ) liqueur powder as filler of urea formaldehyde resin.