静电纺PA 6纳米纤维膜的过滤性能

Filtration performances of electrospun PA 6 nanofiber membranes

用98%甲酸溶解聚酰胺6(PA 6)制备质量浓度为13%纺丝液,经静电纺丝获得厚度31～60μm、纤维平均直径217 nm、表面平均孔径为234 nm的纳米纤维非织造膜。由于该纤维膜的断裂强度仅为8.06 MPa,实验以普通聚酯纤维织物为支撑基布,测试了不同样品的过滤性能。结果发现:在气流速度为2.83 L/min时,普通聚酯纤维基布对1μm微粒的过滤效率仅为9.92%,对0.5和0.3μm微粒无过滤作用;而在基布上覆盖一层面密度为1.25 g/m2的PA 6纤维膜后,对1、0.5和0.3μm微粒的过滤效率分别为92.16%、89.66%和87.38%;当覆盖的PA 6纤维膜面密度达到2.5 g/m2时,相应的过滤效率分别增加到97.03%、96.23%和95.65%,但透气量增加不大。实验结果表明,聚酯纤维基布与静电纺PA 6纤维膜复合材料具有良好的过滤性能,显示出在高效、精密过滤材料中的应用潜力。

PA 6 was firstly dissolved in 98% formic acid to produce the spinning liquor with concentration of 13wt% , and then be electrospun to obtain nanofiber membranes with the thickness of 31 to 60 txm, the average diameter of 217 nm and the surface average pore diameter of 234 nm. Because the breaking tenacity of the membrane was only 8.06 MPa, the polyester fabrics were selected as substrate to provide mechanical support to test the filtration performance of various specimens. The results showed that the filtration efficiency of the general polyester fiber substrate was only 9.92% on filtration of particle of 1 μm while the airflow speed be of 2.83 L/min, and no filtration efficiency on 0.5 μm and 0.3 μm particles, when they were covered with the electrospun PA 6 nanofiber membrane with the density of 1.25 g/m2, they could filter the former specification particles separately on filtration efficiency of 92.16%, 89.66% , 87.38% , respectively. Adopting the electrospun membrane with the density of 2.5 g/m2, the filtration efficiency reached 97.03%, 96.23%, 95.65% for 1 μm, 0.5 μm, 0.3 μm particles, and the permeability did not increased significantly. The excellent filtration performance, combined with a simple production process, suggested tremendous potential application for high-precision filter materials.