ABSTRACT
In this chapter, the authors discuss the relation between diameters and diameter distributions of microspheres and the parameters characterizing processes of their preparations from the earlier synthesized polymers. The diameters of microspheres by solvent extraction and solvent evaporation methods are much larger than the diameters of microspheres obtained by direct synthesis by ring-opening dispersion polymerization of L-lactide (Lc) and the diameters of the particles obtained by spray drying. The diameter distributions of particles obtained from the earlier synthesized polymers were significantly greater than in case of microspheres by dispersion polymerization of Lc. The perspective of obtaining microspheres with well-controlled shape, and diameter distribution was rather vague. The authors aim to investigate other methods, to obtain microspheres with controlled diameters and with low diameter polydispersity. The number average diameter of microspheres obtained from polymers synthesized, by emulsification of polymer solutions followed by solvent extraction and/or solvent evaporation methods, can be controlled by choosing the appropriate conditions at which particles are produced.
