Preparation and Properties of Low Formaldehyde Emission Plywood with Flame Resistance
In order to improve the flame resistance and reduce the formaldehyde emission of plywood, a multifunctional formaldehyde scavenger with flame resistance (FSFR) was prepared and used to treat plywoods bonded with high molar ratio urea-formaldehyde (UF) resin. The weight percent gain (WPG), formaldehyde emission, oxygen index (OI), and bonding strength of plywoods after FSFR treated were measured to evaluated properties of FSFR. The results showed that the formaldehyde emission of the treated plywood was 0.1-0.32 mg/L, which could meet the E0 grade requirement (<0.5 mg/L ). The flame resistance of treated plywood increased significantly and the bonding strength changed little. The formaldehyde emission decreased 96.8 % and OI increased 47.2 % and the bonding strength kept unchanged when FSFR reached 8.87 % compared with that of untreated plywood.