Preparation and Characterization of Waterborne Multihydroxy Crosslinked Polyurethane Hybrid Core–Shell Emulsion

Abstract

The use of waterborne polyurethane (WPU) is becoming increasingly prevalent in the effort to address the issue of glare. However, WPU continues to exhibit certain limitations in terms of its performance, including deficiencies in mechanical properties, and low chemical resistance. Consequently, this study employed polyacrylate (PA) modification to create waterborne polyurethane/acrylate (WPUA) hybrid emulsions with a core–shell structure, aiming to enhance their optical properties. Furthermore, different types of alcohol crosslinkers were added to investigate their effects on the optical and mechanical properties of the coatings. Accordingly, this paper presented the design and preparation of a multihydroxyl crosslinking modified antiglare core–shell PU@PA heteropolymer resin utilizing five different hydroxyl-containing crosslinking agents: polyhydroxy alcohols, trimethylolpropane, pentaerythritol, xylitol, and dipentaerythritol. The impact of selecting crosslinkers with varying hydroxyl numbers as well as optimizing their concentrations on particle size, gloss, and tensile strength of WPUA was thoroughly examined. Results revealed that with xylitol as the crosslinker at a mass fraction of 0.9%, the emulsion's average particle size was 680.6 nm, the gloss of the coating reached 42.8 GU, and the tensile strength was 22.31 MPa. The resulting functional WPUA exhibited excellent optical and mechanical properties, offering new insights for the development of antiglare coatings.