Decreasing in free formaldehyde emission by adding different chemicals into urea formaldehyde (UF) resin used for MDF production

In this study, fiberboards were produced with adding different ratios of formaldehit scavengers to urea formaldehyde resin has 1:1:17 mole ratio (U/F) under the optimized res conditions. Free formaldehyde content, some physical properties such as thickness swelling and water absorption values after 24h in distilled water; some mechanical properties such as internal bond, modulus of rupture and modulus of elasticity were determined. The effect of chemicals and their increasing ratios and decreasing resin ratios were evaluated on some of the physical and mechanical properties and on the changes of free formaldehyde content.It was concluded that the chemicals type, chemicals and resin ratios had different effects on the properties of MDF. It was determined significant decresases on free formaldehyde emission with inscreasing chemical ratios. Furthermore water absorption and thickness swelling values showed increasing tendency while internal bond, modulus of rupture and modulus of elasticity showed decreasing tendency. Moreover, the best results were obtained with amine compounds such as methylamine, cyclopentylamine, propylamine, and ethylamine in terms of pyhsical and mechanical properties and free formaldehit emissions.