Polymerisation initiators

A method of making a polymer, comprising the step of reacting

• i) a polymerization initiator, represented by the following Formula 1 ,
• or a Lewis base adduct thereof, and
• ii) at least one type of polymerizable monomers selected from conjugated olefins and aromatic vinyl compounds,
• wherein
• each M1 is independently selected from lithium, sodium and potassium;
• each R1 is independently selected from (C1-C100) alkyl and (C2-C100) alkenyl, optionally substituted with one or more (C6-C12) aryl groups and optionally linked to the carbon atom C by up to 25 monomer units selected from conjugated diene monomers and aromatic vinyl compounds, especially butadiene, isoprene and styrene;
• each R12 is independently selected from hydrogen, (C1-C10) alkyl, (C6-C12) aryl and (C7-C18) alkylaryl;
• each Y1 is independently selected from a nitrogen atom, a sulfur atom and a silicon atom;
• R3, R4 and R5 are each independently selected from (C1-C18) alkyl, di(C1-C6) alkyl amine (only when Y1 is a silicon atom), (C6-C18) aryl, (C7-C18) alkylaryl and, when Y1 is not a silicon atom, —SiR14R15R16, wherein R14, R15 and R16 are each independently selected from (C1-C18) alkyl, (C6-C18) aryl and (C7-C18) alkylaryl;
• n and o are each an integer selected from 0 and n+o=1 when Y1=N, n=o=0 when Y1=S, and n+o=2 when Y1=Si;
• m is an integer selected from 1, 2 and 3;
• each E is independently selected from (C1-C18) alkyl, (C6-C18) aryl, (C7-C18) alkylaryl and —Y3(R9)(R10)t(R11)u, wherein
• Y3 is selected from a nitrogen atom, a sulfur atom and a silicon atom;
• R9, R10 and R11 are each independently selected from (C1-C18) alkyl, di(C1-C6) alkyl amine (only when Y3 is a silicon atom), (C6-C18) aryl, (C7-C18) alkylaryl, and, when Y3 is not a silicon atom, —SiR20R21R22, wherein R20, R21 and R22 are each independently selected from (C1-C18) alkyl, (C6-C18) aryl and (C7-C18) alkylaryl;
• t and u are each an integer selected from 0 and 1;
• and t+u=1 when Y3=N, t=u=0 when Y3=S, and t+u=2 when Y3=Si;
• s is an integer selected from 0, 1 and 2;
• each F is independently selected from (C1-C18) alkyl, (C6-C18) aryl, (C7-C18) alkylaryl and —Y2(R6)(R7)q(R8)r, wherein
• Y2 is selected from a nitrogen atom, a sulfur atom and a silicon atom;
• R6, R7and R8 are each independently selected from (C1-C18) alkyl, di(C1-C6) alkyl amine (only when Y2 is a silicon atom), (C6-C18) aryl, (C7-C18) alkylaryl and, when Y2 is not a silicon atom, —SiR17R18R19, wherein R17, R18 and R19 are each independently selected from (C1-C18) alkyl, (C6-C18) aryl and (C7-C18) alkylaryl;
• q and r are each an integer selected from 0 and 1;
• and q+r=1 when Y2=N, q=r=0 when Y2=S, and q+r=2 when Y2=Si;
• p is an integer selected from 0, 1, 2 and 3;
• K is selected from nitrogen, >C-H and >C-H and >C-Y3(R9)(R10)t(R11)u, wherein Y3,R9,R10, R11, t and u are independently as defined above.