Preparation Research of PLA Microspheres

Polylactic acid(PLA) microspheres were prepared by O/W emulsion/solvent evaporation method applied PLA as foundation material and polyvinyl alcohol as emulsifier.On the basis of assuring the quality of produced particles,the concentration of emulsifier and other factors in a certain range were adjusted to control the average particle size of microspheres after fixed the confirmable factors.Single factor experiment results showed that there were four factors significantly affected the performance of the microspheres: concentration of PLA and emulsifier,stirring rate and dropping speed.The best process to obtain PLA microspheres sized about 100μm was found through orthogonal-designed experiment:stirring rate was 600r/min,concentration of PLA was 9 %(g/mL),concentration of PVA was 0.5%(g/mL) and the dropping speed was 1.5mL/min.