Montes A., Gordillo D., Pereyra C., Di Giacomo G., Martinez De La Ossa E., 2013, Poli (L-lactide) Micronization by Supercritical Fluids, Chemical Engineering Transactions, 32, 2215-2220.
Polymer microparticles are useful for several applications like stationary phases in chromatography, adsorbents and catalyst supports, as well as drug delivery systems. The application of supercritical fluids for particle precipitation has been developed an ideal alternative to conventional processes in the past decades. In this work Poly(L-lactic acid) (PLLA), a thermoplastic aliphatic polyester derived from renewable resources, such as corn starch, tapioca products or sugarcane has been processed by supercritical fluids, particularly with rapid expansion of supercritical solutions (RESS) and supercritical antisolvent (SAS) processes. RESS process experiments were failed but the morphology was greatly improved from irregular blocks to spherical microparticles in the SAS process. The polymer concentration and pressure effect have been too evaluated. At higher concentration of the initial solution the particle size was decreased. As well when pressure is increased the particle size is decreased.
