2024/10/15 by Ramlow, Heloisa, Ribeiro, Luiz F. B., Schafföner, Stefan +2
#540 #620 #Electrospinning #Oxidation resistance #Polyacrylonitrile #Polymer-derived ceramics #Preceramic polymers
paper · doi:10.15495/epub_ubt_00008002
C-rich SiCN(O) ceramic nonwovens with thermo-oxidation resistance up to 600 °C were developed from electrospinning of polyacrylonitrile in combination with different ratios of an oligomeric or polymeric silazane and subsequent pyrolysis. The influence of the selective pre-polymerization of the oligosilazane and the respective amount on the electrospinning, pyrolysis, phase formation and the properties of the resulting C-rich ceramic nonwovens was evaluated. The fiber diameter after pyrolysis at 1000 °C ranges from 0.26 to 0.63 µm. The oligosilazane/PAN-derived ceramic nonwovens contain high oxygen and carbon content because of high reactivity leading to a high ceramic yield due to additional crosslinking. A higher initial oxidation temperature compared to pure carbon was confirmed for all samples. However, the best result was achieved with a sample based on a high proportion of polysilazane in combination with PAN, as a dense passivating layer to protect the free carbon regions was obviously better able to form.