The suspensions were prepared with 50 vol.% of solid load, using
Dolapix PC 67 (chemical basis: Polycarboxylic acid, sodiumsalt, according
to the data sheet from Zschimmer–Schwarz) as dispersion agent to
stabilize the suspension and to adjust its viscosity close to 0.5 Pa·s,
measured by a Sheen ERV8 Brookfield viscometer. These ceramic
suspensions were combined with previously melted paraffin (Merck
1.07337.2500) at 80 °C, while stirring at 250 rpm, to obtain emulsions
with paraffin:suspension volume ratio of 1.5, followed by addition of a
solution of sodium lauryl sulfate (Sigma-Aldrich L-6026), with concentration
of 1 mg·cm−3, and volume corresponding to 6 vol.% emulsion.
Oxoid LP0008 collagen (5% relative to water volume) was also added,
followed by mechanical stirring at 1000 rpm during 10 min. The
resulting emulsions were then naturally cooled down to room temperature,
to induce solidification of the paraffin droplets, gelatin induced
gelcasting, and shape stabilization, for facile control of humidity