Group transfer polymerization catalyzed by mercury compounds

A Group Transfer Polymerization process that produces a "living" polymer comprising contacting under polymerizing conditions at least one acrylic monomer of the formula CH.sub.2 .dbd.CHC(O)X' with a tetracoordinate organosilicon initiator of the formula

• Q'SiZ, Q"Si(Z.sup.1).sub.2 or [Z.sup.1 (Q")Si].sub.2 O
• wherein:
• Q' is [X"(R.sup.1).sub.q ].sub.3-x (R.sup.1).sub.x);
• Q" is [X"(R.sup.1).sub.q ].sub.2-y (R.sup.1).sub.y ;
• each X", independently, is O, N or S;
• q is 1 or, when X" is N, 2;
• x is 0, 1, 2 or 3;
• y is 0, 1 or 2;
• Z is --OC(X.sup.2).dbd.C(R.sup.2)(R.sup.3), ##STR13## or mixtures thereof;
• Z.sup.1 is --OC(X.sup.2).dbd.C(R.sup.2)(R.sup.3);
• X.sup.2 is --OSi(R.sup.1).sub.3, --R.sup.6, --OR.sup.6 or --NR'R";
• R.sup.6 is:
• (a) a hydrocarbyl radical which is an aliphatic, alicyclic, aromatic or mixed aliphatic-aromatic radical containing up to 20 carbon atoms;
• (b) a polymeric radical containing at least 20 carbon atoms;
• (c) a radical of (a) or (b) containing one or more ether oxygen atoms within aliphatic segments thereof;
• (d) a radical of (a), (b) or (c) containing one or more functional substituents that are unreactive under polymerizing conditions;
• or
• (e) a radical of (a), (b), (c) or (d) containing one or more initiating sites;
• each of R.sup.2 and R.sup.3 is independently selected from H and a hydrocarbyl or polymeric radical defined as for R.sup.6 ;
• Z' is O or NR';
• and
• m is 2, 3 or 4
• and co-catalyst, said process is further characterized in that the co-catalyst is a mercury compound of the formula R.sup.7 HgI or HgL.sub.2,
• wherein the formulas,
• L is I or ClO.sub.4 ;
• X' is --OSi(R.sup.1).sub.3, --R, --OR or --NR'R";
• each R.sup.1, independently, is a hydrocarbyl radical which is an aliphatic, alicyclic, aromatic or mixed aliphatic-aromatic radical containing up to 20 carbon atoms or --H, provided that at least one R.sup.1 group is not --H;
• R is:
• (a) a hydrocarbyl radical which is an aliphatic, alicyclic, aromatic or mixed aliphatic-aromatic radical containing up to 20 carbon atoms;
• (b) a polymeric radical containing at least 20 carbon atoms;
• (c) a radical of (a) or (b) containing one or more ether oxygen atoms within aliphatic segments thereof;
• (d) a radical of (a), (b) or (c) containing one or more functional substituents that are unreactive under polymerizing conditions;
• or
• (e) a radical of (a), (b), (c) or (d) containing one or more reactive substituents of the formula --Z'(O)C--CH.dbd.CH.sub.2 wherein Z' is O or NR';
• and
• each of R' and R" is independently selected from C.sub.1-4 alkyl;
• and
• R.sup.7 is a hydrocarbyl radical having 1 to 10 carbon atoms.