Study of Electrospinning Process: Effect of Viscosity on Morphology of Electrospun PAN/ MWNTs Nanofibers

Electrospinnig process is simple method for preparing nanofibers with diameters ranging from afew nanometers to one micrometer and also this process has been used successfully to fabricate nanocomposite nanofiber polymers cause to improving almost all characterizations of nanofibers of pure polymer. The great interest of using this technique is that its products have some important characters such as large surface–to-volume and length-to-diameter ratios .there are many factors which effect the morphology of electrospun mats such as viscosity of initial solution or concentration of nanoparticle in electrospinning solution. In this paper, nanofiber nanocomposite of multi walled carbon nanotube/poly acrylonitril mats were fabricated. Effect of viscosity on electrospun mat was investigated. Viscosities of initial electrospinnig solutions were evaluated using a Brookfield viscometer and found that viscosity varied between 1050 Cp to 8000 Cp at room temperature. Results reveal that there is viscosity increase with adding MWNTs. Moreover, nanofiber diameters were varied between 300 nm and 800 nm depending on CNTs concentration, and applied voltage. Furthermore, it was observed that for higher concentration of CNTs, an increase in diameter was measured due to two reasons. First it showed that at higher concentration of CNTs the electrical forces preferentially applied on carbon nanotube aggregation rather than polymer. Second, with adding MWNTs, the viscosity increased so fiber diameters of electrospun mats were increased.

کلیدواژه ها:

electrospinning ، multi walled carbon nanotube ، morphology ، nanofiber diameter ، viscosity