Fabrication of Crosslinked Waterborne Polyurethane with Low-Gloss and Micro Roughness for Matting Application

Abstract

A groups of cross-linked waterborne polyurethane (CPU) coatings were successfully synthesized and characterized. The CPU emulsions could achieve low gloss effect without addition of any matting agents by the formation of self-roughed surface. Rheological research shows that the emulsions comply with the Herschel-bulkley pseudoplastic fluid model with a yield stress, and exhibited the same behaviors as the gel. SEM and AFM illustrated the rough surface morphology of the films, and a series of roughness parameters were calculated. In general, the resulted CPU emulsions can provide moderate roughness levels, good hardness and adhesive strengths after film-forming, which were very appropriate for use as matt coating.