Electrospinning Technique And Structure And Performance Of Electrospinning Products

Early in 1934,Formals has mentioned the conception about electrospinning. However, the people have not systematically researched electrospinning theories and made a lot of experiments until recent ten years. Electrospinning is a new development of traditional dry spinning and melt spinning of synthetic fibres. Electrospinning fiber with diameters normally from more than 10 nm to urns is much finer than traditional spun fiber. Electrospinning has been an important method to fabricate super-fine fibers and nanofibers recently. The form of electrospinning fiber product is mainly non-woven fibre membrane. The membrane has high specific surface area, high surface-to-volume ratio and excellent mechanical performance. Therefore, it has the wide application potential in the domain of biomedical material, filtration and composite, and so on.Poly(vinyl alcohol)(PVA)/H₂O solution was used as electrospinning solution and spun to fibers by electrospinning in this research. Basing on designing the electrospinning equipment and comprehending the electrospinning theory deeply, we fabricated nanoscale PVA fiber membrane with good quality of diameter dimension, analyzed influences of electrospinning process parameters on the diameter and morphology of fibers, discussed relations between the structure and performances of electrospinning fiber product with emphasis, expected to offer certain theoretical basis for the electrospinning researches.The results showed: electrospinning process parameters-voltage, distance between capillary and screen(C-SD) and concentration, had important influences on the diameter, morphology and crystal structure of fibers, mechanical performance and air transport performance of the membrane. The diameter of electrospinning PVA fiber increased with the increasing of concentration of the solution; With the increasing of voltage, it increased firstly and decreased later; The broadening of C-SD augmented the diameter of fibers. The enhancing of voltage could reduce the quantity of the beads. The crystal degree of electrospinning PVA fiber was evidently greater than that of PVA powder, and it decreased with the increasing of voltage. It also had the descending trend with the enhancing of C-SD and increased with the increasing of concentration of the solution. The strength and elongation of electrospinning membrane were mainly related with the crystal structure andthe fine degree of fibers and the crossing array state of the membrane. With the increasing of voltage, the elongation of the membrane increased firstly and reduced rapidly later, and the strength of that enhanced; With the broadening of C-SD, the elongation and strength of the membrane both increased firstly and decreased rapidly later; With the increasing of concentration, the elongation of the membrane augmented, and the strength of that decreased firstly and increased rapidly later. The structure of electrospinning PVA fiber membrane was tight, its air transport percentage was little, and its transport performance was poor. The air transport percentage of the membrane reduced with the increasing of voltage. With the increasing of C-SD and concentration, it decreased. Electrospinning PVA fiber membrane had high quality of water absorption, and its dissolution speed in water was much quicker than that of PVA powder. In addition, the regeneration recycle performance the structure and performances of the recycled product were researched.