How do nanoparticles affect the UV shielding efficiency of acrylic coatings?

 

UV-shielding efficiency of water-borne acrylic coatings. Source: Pixabay

 

In a study, nanocomposite coatings based on pure acrylic emulsion and TiO2/or ZnO nanoparticles were prepared and tested with regard to the photostability and UV shielding efficiency.

The researchers used a UV/condensation weathering chamber equipped with UVB-313 fluorescent lamps to study the effect of the nanoparticles.

Promising potential

The results showed that the coatings with the 2 wt% TiO2/or ZnO nanoparticles and a thickness of 45 μm have the highest UV-shielding and photostability. These coatings could shield more than 98% (for TiO2) and 85% (for ZnO) of UV radiations in wavelength range from 230 to 380 nm. After 60 cycles of UV/CON exposure, the colour of coating samples protected by the TiO2 and ZnO nanocomposite coatings changed insignificantly, their adhesion only decreased slightly, from their initial values of 2.5 and 2.4 to the values of 2.3 and 2.1 N/mm2, respectively. These nanocomposite coatings have possibly a promising potential for UV shielding applications.

The study is published in: Progress in Organic Coatings, Volume 110, September 2017, Pages 114–121