Evaluation of mechanical properties and formaldehyde emissions of particleboards with nanomaterial-added melamine-impregnated papers

The effects of various surface hot-pressing parameters, including temperature, time, and pressure, on the properties of particleboards with nanomaterial-added melamine-impregnated papers were investigated. Melamine formaldehyde resin (MUF) mixed with nano-TiO₂-pillared montmorillonite (TiO₂/MMT) was used to impregnate decor papers. Orthogonal experimental design was employed to determine the effects of different factors and to find the optimum levels of the parameters to achieve the most desirable properties. Mechanical and physical properties including modulus of rupture, internal bond strength, thickness swelling, and formaldehyde emission were determined according to Chinese national standards GB/T 15102 (2006) and GB/T 18580 (2001), respectively. With the incorporation of nanoparticles into the MUF resin, the mechanical and physical properties of the coated particleboards improved and formaldehyde emission decreased. Surface pressing temperature and time had a significant influence on the MOR and TS properties, while the pressure was less significant. On the other hand, the presence of nanoparticles in the impregnated resin and heat treatment during surface pressing resulted in less formaldehyde emission. Thus, low-formaldehyde-emission particleboard coated with nano-melamine impregnated papers can be obtained with 60 s of surface pressing at a temperature of 190 °C and pressure of 3.0 MPa.