High definition fibrous poly(2-ethyl-2-oxazoline) scaffolds through melt electrospinning writing

Melt electrospinning writing (MEW), a computer-aided fiber deposition process based on an electrohydrodynamic working principle, enables the rational design and fabrication of fibrous scaffolds with micrometer thin fibers. So far, MEW has mainly been applied for poly(ε-caprolactone). Here we manufactured scaffolds of poly(2-ethyl-2-oxazoline), a hydrophilic polymer with high melting temperature, by MEW for the first time. We systematically varied and investigated the crucial instrument parameters: heating temperature (200–220 °C), feeding pressure (1.0–3.0 bar), accelerating voltage (3.0–7.0 kV) and collector distance (3.0–7.0 mm) in dependence of differently sized spinnerets (23 G, 25 G, 27 G, 30 G). As criteria for homogeneous deposition, we studied the resulting fiber diameters which could be adjusted from 8 μm to 138 μm and the corresponding variances. Furthermore this letter clarifies the need of a dynamic balance between involved mass flows in order to reduce pulsing failures of the jet and thereby structural defects of the deposited structures.