  Here we introduce a versatile stereolithographic route to produce three
different kinds of Si-containing thermosets that yield high performance
ceramics upon thermal treatment. Our approach is based on a fast and
inexpensive thiol-ene free radical addition that can be applied for different
classes of preceramic polymers with carbon-carbon double bonds. Due to the
rapidity and efficiency of the thiol-ene click reactions, this additive
manufacturing process can be effectively carried out using conventional light
sources on benchtop printers. Through light initiated cross-linking, the liquid
preceramic polymers transform into stable infusible thermosets that preserve
their shape during the polymer-to-ceramic transformation. Through pyrolysis the
thermosets transform into glassy ceramics with uniform shrinkage and high
density. The obtained ceramic structures are nearly fully dense, have smooth
surfaces, and are free from macroscopic voids and defects. A fabricated SiOC
honeycomb was shown to exhibit a significantly higher compressive strength to
weight ratio in comparison to other porous ceramics.
