Influences of UF adhesive consumption on HDF properties

In this study, high-density fiberboards were produced using five different Urea-Formaldehyde resin (0.98 mole) consumption amount (12.47, 11.55, 11.12, 10.65, and 10.1 % wt. of dry fiber), and physical, mechanical, and formaldehyde content properties of fiberboards were determined. Tested boards were produced using the continuous through-feed press in an operating factory instead of laboratory-type press equipment. According to results, a linear and stable increase or decrease tendencies with the increase in adhesive consumption was not observed for almost all properties. Contrary, values of properties oscillated with the increase in adhesive consumption. Except for the Surface Soundness (SS), means of the physical and mechanical properties presented significant differences. The most advanced properties was SS by 25.4% when UF consumption was 105 kg/m³. For the physical properties, it was Surface Abrasion by 15.7% improvement at the same consumption amount. For thickness swelling (TS 2h and 24 h) and water absorption 115 kg/m³ consumption provided highest improvement by 15.3%, 6.8% and 8.7% decreases. Therefore, considering all evaluated properties, a common consumption amount could not be determined which pointed out the best improvement. One of the most important points about the panels was the formaldehyde emission value. The FE around 17.6% decreased when UF consumption was 115 kg/m³. However, FE values are determined above the E1 class value which should be reduced for the market.