Journal of Colloid and Interface Science, Vol.199, No.2, 197-205, 1998
Encapsulation of levitated microparticles
Multi-layered polymer microspheres with diameters of order 10 mu m were produced by polymerizing monomer droplets levitated in an electrodynamic balance. The polymer spheres were subsequently coated with additional monomer by combining the levitated particle with a charged droplet of opposite polarity, and the monomer coating was photochemically polymerized to form a solid shell. The thickness of the shell was determined by comparing the angular light scattering with Mie theory. A polymer coating was also applied to levitated NaNO3 particles, and Raman spectroscopy was used to explore the effect of the polymer shell on the Raman signal associated with the salt core, The coating significantly reduced the Raman signal from the salt core, and these results are shown to be consistent with a decrease in the internal electromagnetic field in the salt core computed using Mie theory,
Keywords:FLUORESCENT SCATTERING;CHEMICAL-REACTIONS;POLYMER COLLOIDS;EVAPORATION CHARACTERISTICS;STRUCTURAL RESONANCES;SMALL PARTICLES;COATED SPHERE;RAMAN;AEROSOLS;DROPLETS