Dispersion control of perylene fluorophores in a polystyrene microsphere

ABSTRACT

Polystyrene (PS) microspheres embedding perylene fluorophores have been fabricated by the two kinds of encapsulation method; (A) seed polymerization of styrene using perylene nanocrystals as a seed, and (B) emulsion polymerization of perylene-styrene solution. In both methods, the PS microspheres formed were ca. 200 nm in size, roughly larger than bare perylene nanocrystals. Interestingly, the fluorescence peak positions in both the PS microspheres were located between those of solution and nanocrystal states. These facts suggest that the dispersion state of perylene fluorophores in PS microspheres would be changed to be intermediate between solution and nanocrystal states during the polymerization process.

KEYWORDS:

• Organic nanocrystals
• perylene
• reprecipitation
• polymer microspheres
• encapsulation