静电纺多孔/无孔二醋纤复合膜的制备及过滤性能研究

Preparation of porous/nonporous cellulose acetate composite membrane for air filtration

采用静电纺丝技术,借助高挥发溶剂的制孔性,制备了多孔超细二醋酸纤维。通过调控纺丝过程中多孔超细二醋酸纤维和无孔纳米二醋酸纤维的比例,制备了不同交叉结构的多孔超细/无孔纳米二醋纤复合膜。通过扫描电镜观察纤维膜的形貌,利用电导率仪测试纺丝液电导率,运用黏度计测试纺丝液的黏度,利用多孔材料孔径分析仪测试复合膜的孔径分布,通过滤料综合性能测试台测试不同空气流量下复合膜的过滤性能。结果表明:随着无孔纳米纤维在复合膜中比例的增加,复合膜的孔径分布范围变窄,孔径减小,堆积密度增加;过滤效率和过滤阻力都呈增大的趋势;当纺丝过程中,多孔超细纤维与无孔纳米纤维纺丝针管数目比例为1∶2时,所制备的复合膜具有最好的品质因数,在空气流量为80L/min时,其过滤阻力仅为280Pa,过滤效率可达99.472%。

Cellulose acetate porous ultrafine fibers were produced from highly volatile solvent system by electrospinning.Different kinds of porous fibers/nonporous fibers interlaced structure composite membranes were prepared by adjusting the ratio of porous and nonporous fibers in the composite membranes.The surface morphology of membrane was studied by scanning electron microscopy（SEM）,the conductivity of spinning solution was measured by a conductivity meter.The solution viscosity was measured with viscometer,the pore size distribution of membrane was measured by pore size analyzer and filtration performance of composite membrane with different air flow was measured.The results showed that,with the increasing of content of nano-sized nonporous fiber,the pore size distribution became narrower,the pore size decreased,the packing density of membrane increased,the filtration efficiency and pressure drop increased.And when the spinning jets ratio of ultrafine porous fiber and nano-sized nonporous fiber was 1∶2,the composite membranes had the best filtration performance.The pressure drop was 280 Pa,the filtration efficiency was99.472% when the air flow was 80 L/min.