The present invention relates to a kit comprising a paste A and a paste B, whereby (a) paste A contains (a1) at least one monomer for radical polymerisation； and (a2) at least one barbituric acid derivative as polymerisation initiator； (b) paste B contains (b1) at least one monomer for radical polymerisation； (b2) at least one heavy metal compound as polymerisation accelerator that is selected from the group consisting of heavy metal salts and heavy metal complexes； (b4) at least one alkali or alkaline earth halide； and (b5) at least one complexing agent for the alkali ions or alkaline earth ions (b4) that contains at least two ether groups； and whereby at least one of the pastes A and B contains, as component (a3) and/or (b3), at least one filling agent that is insoluble in (a1) and/or (b1), respectively. The invention also relates to a kit, the use of the kit for producing a paste for mechanical fixation of articular endoprostheses, for covering skull defects, for filling bone cavities, for femuroplasty, for vertebroplasty, for kyphoplasty, for the manufacture of spacers or for the production of carrier materials for local antibiotics therapy, an initiator system, a polymerisable composition, and a form body.
