TY  - JOUR
A1  - Kade, Juliane C.
A1  - Bakirci, Ezgi
A1  - Tandon, Biranche
A1  - Gorgol, Danila
A1  - Mrlik, Miroslav
A1  - Luxenhofer, Robert
A1  - Dalton, Paul D.
T1  - The Impact of Including Carbonyl Iron Particles on the Melt Electrowriting Process
JF  - Macromolecular Materials and Engineering
N2  - Melt electrowriting, a high-resolution additive manufacturing technique, is used in this study to process a magnetic polymer-based blend for the first time. Carbonyl iron (CI) particles homogenously distribute into poly(vinylidene fluoride) (PVDF) melts to result in well-defined, highly porous structures or scaffolds comprised of fibers ranging from 30 to 50 µm in diameter. This study observes that CI particle incorporation is possible up to 30 wt% without nozzle clogging, albeit that the highest concentration results in heterogeneous fiber morphologies. In contrast, the direct writing of homogeneous PVDF fibers with up to 15 wt% CI is possible. The fibers can be readily displaced using magnets at concentrations of 1 wt% and above. Combined with good viability of L929 CC1 cells using Live/Dead imaging on scaffolds for all CI concentrations indicates that these formulations have potential for the usage in stimuli-responsive applications such as 4D printing.
KW  - additive manufacturing
KW  - melt electrospinning writing
KW  - magnetoactive materials
KW  - electroactive polymers
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-318482
SN  - 1438-7492
VL  - 307
IS  - 12
ER  - 
TY  - JOUR
A1  - Bakirci, Ezgi
A1  - Frank, Andreas
A1  - Gumbel, Simon
A1  - Otto, Paul F.
A1  - Fürsattel, Eva
A1  - Tessmer, Ingrid
A1  - Schmidt, Hans‐Werner
A1  - Dalton, Paul D.
T1  - Melt Electrowriting of Amphiphilic Physically Crosslinked Segmented Copolymers
JF  - Macromolecular Chemistry and Physics
N2  - Various (AB)\(_{n}\) and (ABAC)\(_{n}\) segmented copolymers with hydrophilic and hydrophobic segments are processed via melt electrowriting (MEW). Two different (AB)\(_{n}\) segmented copolymers composed of bisurea segments and hydrophobic poly(dimethyl siloxane) (PDMS) or hydrophilic poly(propylene oxide)-poly(ethylene oxide)-poly(propylene oxide) (PPO-PEG-PPO) segments, while the amphiphilic (ABAC)\(_{n}\) segmented copolymers consist of bisurea segments in the combination of hydrophobic PDMS segments and hydrophilic PPO-PEG-PPO segments with different ratios, are explored. All copolymer compositions are processed using the same conditions, including nozzle temperature, applied voltage, and collector distance, while changes in applied pressure and collector speed altered the fiber diameter in the range of 7 and 60 µm. All copolymers showed excellent processability with MEW, well-controlled fiber stacking, and inter-layer bonding. Notably, the surfaces of all four copolymer fibers are very smooth when visualized using scanning electron microscopy. However, the fibers show different roughness demonstrated with atomic force microscopy. The non-cytotoxic copolymers increased L929 fibroblast attachment with increasing PDMS content while the different copolymer compositions result in a spectrum of physical properties.
KW  - melt electrowriting
KW  - 3D printing
KW  - additive manufacturing
KW  - electrohydrodynamics
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-257572
VL  - 222
IS  - 22
ER  -