Porous polylactide particles regulated by phase separation

摘要

Porous poly(L-lactide) (PLLA) particles was produced through the phase separation process of PLLA/o-dichlorobenzene and diethylphthalate systems. The turbid system was obtained from a homogeneous solution of PLLA/o-dichlorobenzene. Spherulites were formed during the phase separation process, and most of the solvent was bound in the spherulites. The cluster radius of the solvent bound in the spherulites was a few tens run. The solvent was extracted by immersing in methanol, and then the particles were obtained. The nanopores were formed after the solvent was extracted. The particle size was regulated from 100 μm to 700 urn, depending on the quenching temperature. The particles have a macroporous structure, with a mesh size of a few μm. The quenching temperature has a strong effect on the porous morphology, which is essentially regulated by the crystallization of PLLA. As a result, it was shown that the porous PLLA particles consist not only of macropores measuring a few μm, but also of nanopores measuring a few tens nm. For the PLLA/diethylphthalate system, the porous particles were obtained by the same procedure. However the particle size was much smaller than that formed by an o-dichlorobenzene solution.