Compounds with guanidine structure and uses thereof as organopolysiloxane polycondensation catalysts

An organopolysiloxane composition comprising:

• (a) a silicone base B comprising at least one polyorganosiloxane oil or gum C crosslinkable via a polycondensation reaction to form a silicone elastomer and (b) a catalytically effective amount of at least one polycondensation catalyst A having the formula (I):
• in which:
• the R1, R2, R3, R4 or R5 radicals, which may be identical or different, represent, independently of one another, a linear or branched monovalent alkyl group, a cycloalkyl group, a (cycloalkyl)alkyl group, the ring being substituted or unsubstituted and being able to comprise at least one heteroatom, or a fluoroalkyl group, an aromatic group, an arylalkyl group, a fluoroalkyl group, an alkylamine group or an alkylguanidine group,
• the R1, R2, R3 or R4 radicals may be linked in pairs so as to form a 3-, 4-, 5-, 6- or 7-membered aliphatic ring optionally substituted with one or more substituents, and
• with the proviso that:
• (1) the R1, R2, R3, R4 and R5 radicals do not comprise a silicon atom, (2) the catalyst does not comprise a compound of formula (A1) to (A3),
• and (3) the composition does not contain any metal catalyst.