Coordination complexes as polyesterification catalysts

Claim 1

In a process for the manufacture of solid fiber-forming polyesters or copolyesters of dicarboxylic acid compounds and aliphatic glycols in the presence of catalysts, the improvement which comprises using as polyesterification catalyst a coordination complex of (A) and (B), wherein: (A) is a metal halide of a metal selected from the group consisting of titanium, zirconium, zinc, germanium, tin, lead, antimony and bismuth; and (B) is a silicon compound selected from the group consisting of: ##STR5## wherein W is ##STR6## X is hydrogen or methyl and is methyl only when m is one; R* is alkyl or haloalkyl having from 1 to 4 carbon atoms; R** is methyl, ethyl, butyl, acetoxy, methoxy, ethoxy or butoxy; R is methyl, ethyl, butyl, methoxy, ethoxy, butoxy or trimethylsiloxy; R' is methyl, methoxy, ethoxy, butoxy or trimethylsiloxy; R" is methoxy, ethoxy, butoxy, trimethylsiloxy or vinyldimethylsiloxy; R"' is methyl, ethyl, butyl or trimethylsilyl; Me is methyl; Z is methyl or W; Q is an NH 2 CH 2 --, NH 2 CH 2 CH 2 NHCH 2 --, NC--, HS-- or HSCH 2 CH 2 S-- group; n is an integer having a value of from 2 to 5; m is an integer having a value of zero or one; x is an integer having a value of from 1 to 100; and y is an integer having a value of from 1 to 100; wherein the mole ratio of A:B in said coordination complex is from 1:1 to 1:7.