Patent ID: 8278407

Claim:
An RTV-organopolysiloxane composition comprising a silicone base B capable of curing via polycondensation reaction into a silicone elastomer and a catalytically effective amount of at least one catalyst system X, wherein: a) the catalyst system X comprises at least one metal complex or salt A of formula (1) below: [M(L 1 ) r1 (L 2 ) r2 (Y) x ] (1) in which the symbols are defined under i), ii) or iii): i) r1≧1, r2≧0 and x≧0; the symbol M is a metal selected from the group consisting of cerium, bismuth and molybdenum; the symbol L 1 is a ligand which is an alcoholate anion derived from a diol and when r1≧2, the symbols L 1 are identical or different; the symbol L 2 is an anionic ligand which is different from L 1 and when r2≧2, the symbols L 2 are identical or different; and the symbol Y is a neutral ligand and when x≧2, the symbols Y are identical or different; or ii) r1≧1, r2≧0 and x≧0; the symbol M is a metal selected from the group consisting of scandium, ytterbium, copper, silver and bismuth; the symbol L 1 is a ligand which is a sulfonate anion and when r1≧2, the symbols L 1 are identical or different; the symbol L 2 is an anionic ligand which is different from L 1 and when r2≧2, the symbols L 2 are identical or different; and the symbol Y is a neutral ligand and when x≧2, the symbols Y are identical or different; or iii) r1≧1, r2≧0 and x≧0; the symbol M is molybdenum; the symbol L 1 is a ligand which is a carboxylate anion and when r1≧2, the symbols L 1 are identical or different, the symbol L 2 is an anionic ligand which is different from L 1 and when r2≧2, the symbols L 2 are identical or different; and the symbol Y is a neutral ligand and when x≧2, the symbols Y are identical or different; and with the proviso that, when the symbol M is molybdenum, the compound of formula (1) selected is in solid form; and further wherein: b) the catalyst system X is prepared according to the following process: step 1: dispersing the metal complex or salt A in at least one oily organopolysiloxane polymer K having a viscosity of at least 100 mPa·s, and step 2: milling the mixture, optionally after kneading, until a homogeneous mixture is obtained, which is the catalyst system X.