Preparation and antibacterial properties of waterborne UV cured coating modified by quaternary ammonium compounds

In this article, the antibacterial properties and mechanism of waterborne UV cured acrylic coatings (WUV) modified by quaternary ammonium compounds (QAC) is discussed, as well as the changes in the antibacterial properties of QAC under the action of different additives. (60 wt% methanol, 60 wt% ethanol, and 75 wt% ethanol). And the chemical cross-linking method is used to combine WUV with QAC. The scanning electron microscopy (SEM), Fourier transforms infrared spectrometer (FTIR), and X-ray photoelectron spectroscopy (XPS) was employed to characterize the modified WUV. The antibacterial properties of three antibacterial agents in liquid coatings (WUV-L) and cured coating films (WUV-C) are investigated. The SEM images showed many irregular wrinkles appeared on the surface of modified coating films. The FTIR result showed the hydroxyl groups promoted the binding ability of the antibacterial agents and coating, and the XPS result revealed that the increase of −NR₄⁺ concentration enhanced the antibacterial properties of coating films. The antibacterial properties of WUV-L and WUV-C improved with the increase of QAC. Theoretical antibacterial agents mass fraction of 5% or higher was found to have the highest antibacterial rate (>90.00%) for WUV modification, among, the WUV modified by QAC-m60 is the best with the antibacterial rate reaching to 99.73% in WUV-L and 99.67% in WUV-C.