I am working on electrospinning of Carboxymethyl Chitosan. I always get drops of polymer solution on Aluminium Foil instead of fibers. I think this is because of High surface tension. Is this true ?
May be, but try with increased percentage of polymer solution. This may solve your issue
Dear Muhammad,
this can be attributed to internal interaction between hydroxyl and amine groups of chitosan in aqueous bed which can deteriorate electrospinning ability of resulted solution by increasin surface tension. That is why researchers usually use concentrated acid or guest polymer like PVA in order to diminish this negative effect.
Article Fabrication and characterization of chitosan/poly(vinyl alco...
When it goes to chitosan electrospinning solution surface tension is a vital factor which is directly correlated to internal interaction between its active groups. Of course when we consider surface tension as an effective factor in electrospinning generally without considering chitosan polycationic characteristics your statement would be very true.
Hi Maqsood, first try spinning at higher voltage with the same concentration or viscosity you are using now. If not you have to play around the concentration of polymer solution as well.
For my opinion surface tension of normal acidic chitosan solutions is the key point for interfering with nanofibre generation by electrospinning. As already mentioned by Siavash you need to disturb the hydrogen bridges between hydroxylic and amino groups to enable spinning. Apart from high concentrations of acids or the addition of interfering polymers you can use very strong acids as TFA.
Hi,
It could be attributed to a number of factors. One of them is the rate at which the solution is flowing from your syringe. Try decreasing the rate. Also, it might be due to the low viscosity of your solution, or even having a solvent that does not evaporate easily.
Dear friends,
you should notice that in the question "chitosan" mentioned as polymer. Therefore, we are not talking about basic factors contributing to the formation of fiber in the electrospinning. Electrospinning of chitosan is challenging due to its polycationic behaviour originated from internal intercation between its amino and hydroxyl groups that cause considerable increase in the solution surface tension. Thus, we need to decrease it by using concentrated acid or strong acetic acid, TFA or using compatible guest polymer like PVA OR PEO to diminish the internal interaction between chitosan active groups.
Regards
Firstly, do not change the voltage and flow rate and then change the solution concentration and viscosity and then see the result.
Most commonly low concentration is the reason behind drops, try to increase the concentration.
Polymer concentration and applied voltage are among the most influential parameters of electrospinning which define whether we synthesis nanofiber or not by increasing voltage and decreasing solution concentration you may produce nanofiber.
Try increasing the viscosity of your solution. The morphology changes from droplets to nanofibers based on increase in the viscosity of your solution. You can introduce additives like PEO to make your solution more electrospinnable. Please find an article attahced; this will help you in troubleshooting.
i am facing the same problem even with increased polymer concentration sometimes
- Badges
- Science topic
- Similar topics
- Physical Sciences
- Materials Science