Abstract:
Surface treatment of polycarbonate (PC) was carried out by atmospheric air plasma treatment technology, sandpaper grinding and coating primer. The contact angle, functional groups, micromorphology and chemical elements of PC surface were characterized, and polyurethane sealant was used as adhesive, combined with peel failure morphology and tensile shear test. The influence of different surface treatments on the surface bonding properties of PC was studied. The results show that compared with no surface treatment, the contact angle between PC surface and water and ethylene glycol was decreased after plasma treatment, the content of polar oxygen functional groups on the surface was increased, the surface wettability was improved, the surface failure mode was the same as sanding treatment, and it is still the interface adhesion failure. The tensile shear strength of the two surface treatments was slightly improved, and the bonding property was not significantly improved. After primer coating treatment, the surface morphology changed from the nano-scale grooving pits without surface treatment to the smooth surface of water wave, and the surface water contact angle decreased slightly, the surface polar oxygen-containing functional group content increased, the surface failure mode changed to adhesive cohesion failure, the tensile shear strength increased by about 13 times, and the bonding property was significantly improved.