Synthesis of polystyrene spheres with various sizes by controlling synthetic condition

Abstract

Nowadays nanoparticles are used in many part. Due to their electronic, optical and catalytic properties they are used as exciting building blocks for nanoscale assemblies, structures and devices. Furthermore characteristic electrical charging properties of these particles, as well as their optical and photophysical features allow the addressing of particles by external electronic and photonic signals. Nanoparticles also have been used in fillers for improvement of mechanical properties of some materials. Nanoparticles have been used in photonic crystals, too. Moreover they can be used in special paints or inks. In addition to these engineering applications nanoparticles are used in biological applications. Nanoparticles can be used in drugs, peptides, vaccines, oligonucleotides and gene delivery system. Nanoparticles are also utilized in biological imaging because they do not show harmful influence to cell. In these days nanoparticles are used in Light-emitting diode (LED). Nanoparticles are usually coated on the sapphire substrate and various properties of LED are improved by it. In these nanoparticles polystyrene sphere is widely used. So to raise understanding of polystyrene sphere and to synthesize various sizes of polystyrene sphere effectively are become goal of this study. At first relations between various factors and size of polystyrene sphere were investigated. Factors were polarity of solvent, concentration of monomer, concentration of stabilizer and concentration of initiator. Decrease of polarity of solvent causes increase of size of polystyrene sphere. Increase of monomer concentration in solvent causes increase of size of polystyrene sphere, too. Increase of stabilizer concentration in solvent causes decrease of size of polystyrene sphere. Finally increase of initiator concentration in solvent also causes increase of size of polystyrene sphere. At second using the relationships between various factors and the size of polystyrene sphere specific sizes of polystyrene nanospheres were synthesized. The target diameters of polystyrene spheres were 200 nm, 300 nm, 400 nm respectively. The polystyrene sphere whose diameter is about 220 nm and the polystyrene sphere whose diameter is about 300 nm were easily synthesized repeatedly. However, reproducibility of the polystyrene sphere whose diameter is about 400 nm was not good. Finally polystyrene sphere whose diameter is larger than 1000 nm was synthesized. For this kind of initiator and solvent are changed and also polarity of solvent, concentration of stabilizer and concentration of initiator was controlled respectively. As a result relationships between factors and the size of polystyrene sphere are same and control of polarity of solvent was most efficient method.