Techniology & Performance Research Of Electrospinning & Electret Meltblown Compound Nonwoven Material

By now, electrospinning technology is one of the main methods of producing nano-fibers. And it attracts great attention by the scientific research personnel at home and abroad. Electrets technology can make nonwoven materials achieving the steady charge on the surface, which can strengthen the adsorption function of filtration materials during the filtering process. Although this technology has already put in actual production, the research of combining electrospinning and electret technology is at the beginning stage. In this research, electrets PET meltblowns were used as the collecting materials for PET electrospinning and PET nanofibers were deposited on the surface of PET mefltblown. By this method, kind of high efficiency filtration materials were prepared.In this paper, PET meltblown nonwoven materials were used as foundation to receive PET electrospinning nanofiber. The mixed solution of trifluoroacetic acid and dichloromethane (volume ratio 1:1) were chosen as the electrospinning spinning solvent. By analysing the fiber microstructure produced in different electrospinning conditions, the conclusions were got:the optimal conditions of PET electrospinning-solution concentration are 25%; the spinning voltage 25 kv; the feeding speed of the spinning solution 0.8 ml/h.Started with the change of PET electrospinning spinning solution concentration, the electrospinning voltage and the feeding speed of the spinning solution, it is found that:1. With the other conditions invariable, when the spinning solution concentration increases in 20%～25%, the fiber average diameter will increase and the droplet phenomenon will gradually disappear. When the spinning solution concentration is 25%. there is almost no small droplet, and at the same time fiber diameter is minimum.2. With the other conditions invariable, when the spinning voltage increases in 20kv～30kv, the fiber average diameter is firstly reduce, and then increase. When the spinning voltage is 25kv, the fiber morphology is more uniformity. When further increasing the spinning voltage, the spinning fiber will excessively draft, and will appear broken section.3. With the other conditions invariable, when the feeding speeds of the spinning solution increases in 0.6 ml/h～2.0 ml/h, as the jet of solute in unit time increasing; the fiber average diameter will increase. The optimal feeding speed og solution is 0.6ml/h.When the meltblown nonwovens with the electret pretreatment were used for the depositing of PET electrospinning nanofibers, the fiber average diameter decreases for higher drawing of spinning solution at the invariable spinning parameters. When the electrets treatment was processed after PET electrospinning on PET meltblown, it has higher filtration efficiency for sodium chloride aerosols testing. And the filtration performances of them were better than that of PET electrospinning materials or PET meltblowns. It is obvious that the electret pretreatment can optimize the performance of electrospinning product and strengthen filtering precision, so it is feasible in filtering products application field.