Gradual Precipitation to Fabricate PLLA Materials with High Porosity and Tunable Strength Formed by High Crystalline Nanosheets

In this study, a facile method about generating porous poly (L-lactide) (PLLA) materials with uniform morphology by gradual precipitation is reported. By adjusting the solvents, concentrations of polymer solution, and drying process, petal-like PLLA nanosheets can be conveniently obtained, which can further form porous materials with tunable porosities (85-92%). X-ray diffraction affirms that a-form crystals of PLLA with high crystallinity (51.66% according to differential scanning calorimetry) can be obtained. Mechanical test shows that the compression modulus is tunable with values ranging from 1.76 to 19.98 MPa. Notably, because of its high porosity, interconnected pore structure, and tunable mechanical properties, these versatile porous materials are especially fit for being utilized in polymer scaffold field.