Self-Assembled Polymer-Grafted Nanoparticles for Photonic Coating Applications

Control of a regular arrangement of nanoparticles and their mechanical stability in a form of arrays and films becomes important in various particle-based technologies such as photonic bandgap materials. Here, we present that polymer-grafted nanoparticles (i.e. polystyrene-grafted silica nanospheres), synthesized by surface-initiated atom radical polymerization (SI-ATRP), can achieve ordered yet mechanically robust films by tuning the polymer brush architecture such as molecular weight and grafting density. Evolution of the particle arrangement in the polymer-grafted nanoparticle films is observed and associated with their wavelength at the maximum reflectance as well as their mechanical characteristics. This could open up new opportunities for fabrication of durable and highly ordered colloidal crystal structures such as photonic coating applications.