Silicone rubber compositions and long-term-stress-resistant silicone elastomers obtained therefrom

A crosslinkable silicone rubber composition comprising

• (A) 100 parts by weight of at least one polydiorganosiloxane comprising organosiloxy units having Si-C-bonded, aliphatically unsaturated groups, polydiorganosiloxane (A) having
• (a) a mean degree of polymerization of from 3000 to 10,000,
• (b) from 0.2 to 20 mol % of organosiloxy units comprising aliphatically unsaturated groups, and
• (c) a low-segregation distribution of the organosiloxy units comprising aliphatically unsaturated groups, with the proviso that the block number R is ≧180·Xa·(1−Xa), where Xa is the mole fraction of these organosiloxy units.
• (B) 1-90 parts by weight of at least one reinforcing filler which is present as a finely divided, inorganic solid having a specific surface area of at least 30 m2/g,
• (C) 0.1-20 parts by weight of at least one crosslinker,
• (D) 0-10 parts by weight of a polydiorganosiloxane which is terminated by vinyldiorganosiloxy groups at both ends, whose non-terminal units are free of aliphatically unsaturated groups, and which has a mean degree of polymerization of from 3000 to 10,000,
• (E) 0-200 parts by weight of one or more further constituents selected from the group consisting of nonreinforcing fillers, talc, quartz flour, inhibitors, catalysts, plasticizers, pigments, stabilizers, flame-retardant additives, bonding agents, mold release agents, hollow microspheres and mixtures thereof,