空气过滤用聚丙烯腈静电纺纤维膜的制备及其性能

Preparation and properties of polyacrylonitrile nanofiber membranes used for air filtering by electrospinning

为开发用于空气过滤的纳米纤维,采用静电纺丝技术制备了聚丙烯腈(PAN)纳米纤维膜,探讨了其纺丝液质量分数及纺丝电压对所纺纤维微观形貌的影响,同时研究了纤维膜厚度对过滤效率和压降的影响。实验结果表明:PAN纺丝液质量分数为12%,纺丝电压为20 k V时,所得纤维粗细均匀,平均直径为230 nm;当纤维膜厚度由18μm增至35μm时,过滤压降则由121.93 Pa升至591.75 Pa,而过滤效率由81.78%升至99.24%。对过滤性能较好的纤维膜分别进行力学性能和泡压法滤膜孔径测试,测得此纤维膜的弹性模量为223.67 MPa,断裂伸长率为51.96%,拉伸断裂应力为5.93 MPa,拉伸强度为7.77 MPa,拉伸屈服应力为2.79 MPa,平均孔径为2.064 3μm。

In order to develop nanofibers for air filtering,polyacrylonitrile（PAN） nanofiber membranes were prepared by electrospinning.The influence of spinning solution concentration and electrospinning voltage on microstructure of the electrospun nanofibers,as well as the influence of membrane thickness on filtration efficiency and pressure drop were investigated.The results show that when the concentration of PAN spinning solution is 12% and the voltage is 20 kV,the well-distributed nanofibers with mean diameter of 230 nm can be formed.The pressure drop increases from 121.93 Pa to 591.75 Pa when membrane thickness increased from 18 μm to 35 μm,while the filtration efficiency of DOP aerosol particle sized 0.33 μm increases from 81.78% to 99.24%.Besides,mechanical properties and pore size distribution determined by the fiber diameter with the better filtration efficiency were tested.Results reveal that its elastic modulus is 223.67 MPa,elongation at break is 51.96%,tensile fracture stress is5.93 MPa,tensile strength is 7.77 MPa,tensile yield stress is 2.79 MPa,and the average pore size tested by bubble pressure method is 2.064 3 μm.