Initiation system comprising a silylated initiator for anionic (co)polymerization of (meth)acrylic monomer(s) and process using same

An initiation system for anionic copolymerization of (meth)acrylic monomers comprising (1) either one or more monofunctional initiator(s) or one or more difunctional initiator(s), characterized in that these initiators are silylated compounds chosen from among:

• monofunctional silylated initiators of Formula (I):
• wherein:
• R1, R2, R3 each independently represent an alkyl radical, linear or branched, containing 1 to 8 carbon atoms;
• R4 represents an alkylene radical, linear or branched, containing 1 to 8 carbon atoms;
• M designates an alkaline metal or alkaline earth (valence q is 1 or 2), or the difunctional silylated initiators of Formula (II):
• wherein:
• R5and R6 each independently represent a linear or branched alkyl radical containing 1 to 8 carbon atoms;
• R7 and R8 each independently represent a linear or branched alkylene radical containing 1 to 8 carbon atoms;
• and
• M′ designates an alkaline metal,
• and (2) at least one alkaline metal alcoholate as ligand.