Adhesion performance and film formation of acrylic emulsion coating on medium density fiberboard treated with Ar plasma

This work investigates the adhesion properties of medium density fiberboard (MDF) panel surfaces treated by an argon plasma at two power levels (50 and 150 W) and four glow discharge times (10, 40, 60 and 120 s) and then coated with an acrylic emulsion. Wettability parameters and film formation kinetics were investigated by water apparent contact angle and diffusing wave spectroscopy, respectively. Pull-off strength was used to determine coating/wood adhesion. The aging effect of 300-days in storage at ambient conditions was examined by apparent contact angle measurements. The wettability of the MDF surface was enhanced significantly - especially at the 150 W power level – that improves coating/wood adhesion. A film formation process occurred in shorter time for plasma treated samples due to the faster motion of particles. MDF panels partially recovered their natural hydrophobicity in the first ten days of storage. Nevertheless, higher levels of power and time of glow discharge were able to slow down the aging effects.