Adjustment of polymer-derived ceramics for the transport of cryogenic liquid
The focus of this research project is the development of hybrid ceramic and SiOC ceramic materials, which should be adapted to the requirements of capillary transport of cryogenic liquids with particular regard to the materials porosity and its surface chemistry. The target structure should have a macro or a micro / macro porous structure, where the wettability of the hybrid materials should be adjusted by the choice of the precursor, the choice of filler material and the pyrolysis temperature. The development of innovative new transport structures centre on hybrid ceramic materials (called "ceramers"), which are generated by an inert gas pyrolysis of polysiloxanes at lower temperatures of 400-700 °C. The micro structure of these materials is in between the base polymer and an amorphous SiOC hybrid ceramic, which is why very promising properties are obtained for the predominantly micro porous ceramers. For these materials the hydrophilic and hydrophobic properties could be controlled much more direct and targeted by the precursor compound and the pyrolysis temperature (see figure), what is crucial for applications in selective adsorption and separation processes. Beside a varied macro and micro- /macroporosity in this research project the surface characteristics of hybrid ceramics are specifically adapted to the very specific conditions that are necessary for the transportation of cryogenic liquids such as H2 and O2. Since the interaction of ceramic materials withcryogenic liquidshas been studied rarelyso far, the predictios of suitable target structurecan only be rough at the beginning, but should be refined in the course of the project in close collaborationwith the project P11/01 "Application of porous ceramics for the handling of cryogenic media in space".