3D porous poly(l-lactic acid) materials with controllable multi-scale microstructures and their potential application in oil-water separation

Hydrophobic PLLA porous materials exhibits excellent oil-removal performance, fabricated by a simple slow solvent-evaporation induced precipitation method, which is of significance for curbing oil-pollution environment. Therefore, porous PLLA materials with tunable microstructures (fibrous networks, microsphere and multiple structures) were conveniently manufactured by adjusting the preparation parameters, solution concentration and precipitation temperature. The results show the wettability of the prepared porous materials could be controlled by the tailorable hierarchical structures. The apparent contact angle of porous PLLA materials was 121°, significantly improved in contrast with 67° of the solvent-casting bulk PLLA film. Moreover, the PLLA materials with high porosity up to 48.4% were obtained from 5 wt% PLLA chloroform solution at the precipitating temperature of 30 °C. Predictably, due to the favorable porosity and the excellent surface hydrophobicity, the porous PLLA materials have great potential in the wild application of oil-water separation.