Waterborne epoxy resins modified by reactive polyacrylate modifier with fluorinated side chains

Abstract

Waterborne difunctional polyacrylate with long fluorinated side chains and epoxy groups (WALF) was successfully synthesized and used as emulsifier and reactive surface modifier for epoxy resin. The structure of WALF was characterized by FTIR and 1H NMR. In order to investigate the effect of the length and the content of the fluorinated side chains on the properties of the epoxy thermosets, a waterborne difunctional polyacrylate with short fluorinated side chains and epoxy groups (WASF) was developed as a contrast modifier. The waterborne epoxy emulsion modified by WALF or WASF was prepared through phase inversion method. Transmission electron microscopy (TEM) signified that the waterborne epoxy emulsion has a particle size range of 201.4–590.2 nm, indicating excellent water dispersion property. In addition, the surface properties, thermal properties, and mechanical properties of the waterborne epoxy coating were also analyzed in detail. Compared with WASF, the epoxy coating modified by WALF had higher surface fluorine atomic concentration, lower surface energy, and higher thermal stability.