| With the fast development of outdoor applications of wood-plastic composite, the aging properties of it cause more and more people’s attention. Coating is a key pathway to increase the added value and expand applications of wood-plastic composite (WPC) by enhancing its anti-aging properties and decorative effects. In this paper, six types and sixteen kinds of coatings including wood wax, acrylate, polyurethane, fluorocarbon, silicone and acrylic polyurethane based coatings were employed to paint polyethylene (PE)-based and polypropylene(PP)-based WPC samples. The coating contact angle and film adhesion were tested to evaluate the finishing performance. Tests were carried out in accordance with the corresponding standards of polyolefin composites, including artificial accelerated ultraviolet aging, film adhesion test and composite mechanical performance test. The mechanical performance changes were characterized by static bending test and impact test. This study laid a preliminary theoretical foundation for the finishing of the polyolefin wood-plastics composites.The results showed that:(1)The contact angle of PE-based WPC was lower than that of PP-based WPC, while the contact angle between waterborne coating and WPC material was higher than that of organic solvent coating based on the same film-forming resin.(2)The film adhesion varied from the types and kinds of the coatings, while the film adhesion between PP-based WPC and most coatings were slightly higher than that of PE-based WPC. Based on the comprehensive consideration of the factors of the coating contact angle, film adhesion and appearance, five types of coatings including wood wax, polyurethane, fluorocarbon, organic silicon, and acrylic polyurethane based coatings were good, wherein the organic silicon and acrylic polyurethane based coatings were better.(3)The artificial accelerated ultraviolet aging test for polyolefin base all affect the performance of wood-plastic composite, but after finishing the polyolefin wood-plastic composite has been effectively protected, and coated with colored paint sample for the color of the pigments in the paint, and the material of the brightness and color change is relatively small, has good resistance to brightness, color change effect, coated with varnish of WPC, change to a larger color lightness, without any coating to protect the WPC, brightness, color change is very big.(4)Increases with the aging time film adhesion in Oh-1000h decreased gradually, in the1000h to1500h a few film adhesion improved slightly, fluorine carbon, acrylic polyurethane enamel coating of these two kinds of coatings film adhesion coating performance is slightly better than others. |
