| abstract |
Methods of making polyurethane compounds include mixing polyols, polyisocyanate compounds and catalysts together, and curing the mixture to form polyurethanes, the catalysts from Ti, Zr, Hf, Al, Fe, Bi or Sn. The metal selected and a) the number of anionic donor sites are x, b) the number of neutral donor sites capable of forming coordination bonds with the metal is y, c) (x + y) is 5 to 8, d) x is 2 to 4 and e) the neutral complex of the multidentate organic ligand, wherein the ligand molecule has a size and shape such that each anionic donor site and the neutral donor site can form a bond with the same metal atom It is characterized by that. |