Polycaprolactone/chitosan blend nanofibres electrospun from an acetic acid/formic acid solvent system

Blend nanofibres composed of chitosan and polycaprolactone (PCL) are highly valuable for biomedical
applications since the benefits of natural and synthetic polymers are thus combined. Research towards
the stable and reproducible electrospinning of these blends is, however, essential. Therefore, this paper
focuses on the novel solvent system 3/7 acetic acid/formic acid for electrospinning PCL/chitosan nanofibres.
Addition of chitosan to PCL solutions led to a significant increase in the solution's conductivity
because of the polycationic character of chitosan. Moreover, since adding chitosan also considerably
raised the viscosity, polymer solutions with a low total polymer concentration could be electrospun.
Owing to both effects, the fibre diameter and distribution were significantly lowered with increasing
chitosan content. Furthermore, chitosan led to the formation of an ultrafine nanofibrous web formed in
between the main fibres. In conclusion, the solvent mixture acetic acid/formic acid is an excellent system
for successfully electrospinning blend nanofibres containing PCL and chitosan.