A comparative study of jet formation in nozzle‐ and nozzle‐less centrifugal spinning systems

Abstract

Centrifugal spinning, a recently developed approach for ultra-fine fiber production, has attracted much attention as compared with the electrospinning, due to its high yield, no solution polarity and high-voltage electrostatic field requirements, etc. In this study, the jet formation process and spinning parameters on jet path are explored and compared in nozzle-and nozzle-less centrifugal spinning systems. For nozzle-less centrifugal spinning, fingers are formed at the front of thin liquid film due to the theory of Rayleigh-Taylor instability. We find that the lower solution concentration and higher rotational speed favor the formation of thinner and longer fingers. Then, the critical angular velocity and initial jet velocity for nozzle-/nozzle-less centrifugal spinning are obtained in accordance with the balance of centrifugal force, viscous force, and surface tension. When jet leaves the spinneret, it will undergo a series of motions including necking and whipping processes, and then, a steady spiral jet path is formed with its radius getting tighter. Finally, we experimentally study the effect of rotational speed and solution concentration on jet path, which shows that the higher rotational speed results in a larger radius of jet path while the solution concentration has little effect on it.

A review of nanofibrous structures in lithium ion batteries

“…The polymer jet further elongates into a fiber, guided by the centrifugal and frictional forces between the jet surface and the air. Processing parameters that influence the final fiber morphology include the angular velocity applied, nozzle diameter, and the spinneret-collector distance [115,116].…”

Evaluation of the effective forcespinning parameters controlling polyvinyl alcohol nanofibers diameter using artificial neural network

“…[13] Among these, electrospinning is the most commonly used technique for creating organic and inorganic ultra-fine fibers in a wide range from micron to nano scales. [16] Over the past few years, a novel process, forcespinning, apart from electrospinning restrictions for the fabrication of submicron fibers, has been developed. [16] Over the past few years, a novel process, forcespinning, apart from electrospinning restrictions for the fabrication of submicron fibers, has been developed.…”

“…[16] Over the past few years, a novel process, forcespinning, apart from electrospinning restrictions for the fabrication of submicron fibers, has been developed. [16] Furthermore, increased production of nanofibers from 0.1 g/h in laboratory-scale electrospinning to over 1 g/min per nozzle is another advantage of centrifugal spinning. As a result, not only conductive polymers, but also nonconductive substances can be spun in solutions or in melts.…”

“…[19] As the conventional methods are able to fabricate fibers with diameters ranging from 10 μm to 10 nm, [16] control and regulation of the process peculiarities is very important to obtain desired fibers. [19] As the conventional methods are able to fabricate fibers with diameters ranging from 10 μm to 10 nm, [16] control and regulation of the process peculiarities is very important to obtain desired fibers.…”

“…[19] As the conventional methods are able to fabricate fibers with diameters ranging from 10 μm to 10 nm, [16] control and regulation of the process peculiarities is very important to obtain desired fibers. [16] Also, a lower polymer concentration leads to a thinner fiber diameter and narrower fibers size distribution, while the rotational speed has a subtle effect on the fiber diameter. The polymer concentration has the significant effects on the fibers morphology, whereas the adjustment in below and above a critical solution concentration leads to the formation of beads to continuous forcespun fibers, respectively.…”