The formation of the S-shaped edge-on lamellae on the thin porous polylactic acid membrane via phase separation induced by water microdroplets

Biodegradable polymers have received increased attention due to their potential application in the medicine and food industries; in particular, poly(lactic acid) (PLA) is a primary biopolymer because of its excellent biocompatibility and absorbability features. In this study, a porous PLA membrane was fabricated by phase separation using water microdroplets produced by an ultrasonic atomizer as a coagulation bath. The formation of S-type clusters was attributed to the slow exchange rate between solvent and coagulant, which provided time for the movement of polymer molecules. The effect of preparation conditions on the structure of S-type clusters, including polymer concentration in solution and ambient temperature was investigated. The PLA porous membrane prepared from water micro-droplets with different morphology compared with the sample fabricated from distilled water has potential application in fields of tissue engineering and artificial organ generation. (c) 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43355.