[en] This thesis fits into the general pattern of the studies carried out by CEA/DEN on the future nuclear systems. The actions proposed in this context consist in synthesizing organo mineral solids from molecular precursors and to implant actinides from a solution to form a primary phase and then to transform this phase into a mineral solid in order to form a secondary phase by an appropriated treatment. The obtained material could be used as raw material for fuel preparation or as incineration target. The retained precursors to contribute to the primary phase are of poly-silanes or poly-carbo-silanes type. At first, these retained polymers have been synthesized. At the present time, two different considered methods are studied in order to obtain polymers with a control porosity and to be able to implant actinides. These synthesis methods are presented in this work. (O.M.)