超声雾化喷涂工艺制备醋酸纤维素多孔膜

聚合物多孔膜在纳米合成、生物电子、清洁能源等新兴领域扮演着重要的角色。为探索面向高性能多孔膜制备的新工艺，基于相转变原理，采用超声雾化喷涂技术实现了孔径、孔隙率可调的醋酸纤维素多孔膜制备。多孔膜的孔隙率随着"聚合物-溶剂-非溶剂"三元体系中非溶剂比例提高而提升，其孔径可通过改变喷头与基底间的距离予以调控。基于"醋酸纤维素-丙酮-水"三元体系，采用醋酸纤维素质量分数为2%、醋酸纤维素与水质量比为1∶4的前驱体溶液，在喷头与基底间距为3 cm的条件下制备了平均孔径为171 nm、孔隙率为58%、断裂强度为3. 42 MPa的醋酸纤维素多孔膜。与流延工艺相比，超声雾化喷涂技术制备的醋酸纤维素多孔膜具有更规整的孔结构，提高了其在纳米合成、锂电池和生物传感等领域中的应用潜力。

Polymer porous membranes play a key role in nanoscale synthesis, bioelectronics, and renewable energy. To develop alternative processes for the fabrication of high performance porous membranes, ultrasonic spraying was used to prepare cellulose acetate (CA) porous membranes with tunable porosity and pore size, based on phase conversion method. The porosity of the as-prepared membrane increases as the proportion of nonsolvent increases in the ternary system of polymer-solvent-nonsolvent. The pore size can be adjusted by varying the distance between the nozzle and substrate. Based on the ternary system of CA-acetonewater, a CA membrane with an average pore size of 171 nm, a porosity of 58%,and a breaking strength of 3.42 MPa was prepared, when the weight percent of CA was 2%,the weight ratio of CA/water was 1∶4,and the distance between the nozzle and substrate was 3 cm. Comparing to tape casting, ultrasonic spraying leads to more regular porous structure in the membrane, which significantly improves the potentiality of porous membranes in the application of nanoscale synthesis, lithium batteries, and biosensors.