Surface modification of high heat resistant UV cured polyurethane dispersions

To modify the surface of UV cured polyurethane dispersion (UV-PUD), fluorinated PU called surface modifying agent (SMA) was blended with base PU prior to dispersion in water. X-ray photoelectron spectroscopy (XPS) and contact angle measurements showed that surfaces of dispersion cast film are significantly enriched with fluorine groups. Atomic force microscopy (AFM) showed that surface was roughened with the addition of SMA, which provided possible mechanism of increased water resistance as well as low friction coefficient of the film. On the other hand, hardness, mechanical and dynamic mechanical properties indicated that the bulk properties are marginally altered by the additive amount of SMA.