Patent ID: 6060572
Filing Date: 2000-05-09
Classification: C08F,F16G,Y10S

Abstract:
An elastomer obtained from the liquid phase polymerization of ethylene, at least one other .alpha.-olefin and, optionally, it least one diene monomer to provide an elastomer, the process comprising polymerizing the monomer under liquid phase polymerization conditions in the presence of a catalytically effective amount of catalyst comprising the product obtained by combining a metallocene procatalyst with a cocatalyst, the metallocene procatalyst being at least one compound of general formulae (I) and/or (II):(Cp.sup.1 R.sup.1.sub.m)R.sup.3.sub.n (Cp.sup.2 R.sup.2.sub.p)MX.sub.q(I)(Cp.sup.1 R.sup.1.sub.m)R.sup.3.sub.n Y.sub.r MX.sub.s (II)wherein Cp.sup.1 of ligand (Cp.sup.1 R.sup.1.sub.m) and Cp.sup.2 of ligand (Cp.sup.2 R.sup.2 p) are the same, or different cyclopentadienyl rings, R.sup.1 and R.sup.2 each is, independently, halogen or a hydrocarbyl, halocarbyl, hydrocarbyl-substituted organometalloid or halocarbyl-substituted organometalloid group containing up to about 20 carbon atoms, m is 0 to 5, p is 0 to 5 and two R.sup.1 and/or R.sup.2 substituents on adjacent carbon atoms of the cyclopentadienyl ring associated therewith can be joined together to form a ring fused to the cyclopentadienyl ring, the fused ring containing from 4 to about 20 carbon atoms, R.sup.3 is a bridging group bridging Cp.sup.1 and Cp.sup.2, n is 0 or 1, Y is a heteroatom-containing group in which the heteroatom is coordinated to M, M is a transition metal having a valence of from 3 to 6, each X is a non-cyclopentadienyl ligand and is, independently, halogen or a hydrocarbyl, oxyhydrocarbyl, halocarbyl, hydrocarbyl-substituted organometalloid or halocarbyl-substituted organometalloid group containing up to about 20 carbon atoms, q is equal to the valence of M minus 2, r has the value of n and s is equal to the valence of M minus 1 the valence of M minus 2, r has the value of n and s is equal to the valence of M minus 1 when r is 0 and is equal to the valence of M minus 2 when r is 1, the cocatalyst being an aluminoxane or a different cation-generating cocatalyst comprising: a metal- and/or metalloid-containing first component capable of exchanging at least one X ligand in the metallocene procatalyst up to the total number thereof with, independently, a hydrogen atom, or a carbohydryl group containing up to about 20 carbon atoms or an oxycarbohydryl group containing up to 20 carbon atoms; a neutral metal- and/or metalloid-containing second component having at least one aryl group possessing at least one electron-withdrawing substituent; and, an anionic metal-containing third component having at least one aryl group possessing at least one electron-withdrawing constituent alone or in combination with a metalloid-containing third component having at least one aryl group possessing at least one electron-withdrawing constituent, provided, that when the metallocene procatalyst is one of formula (I) and the cocatalyst is entirely an aluminoxane, or combination of aluminoxane and added trialkylaluminum, ligand (Cp.sup.1 R.sup.1.sub.m) is different from ligand (Cp.sup.2 R.sup.2.sub.p), bridging group R.sup.3 contains at least two bulky groups and n is 1 and when the procatalyst is entirely one of formula (II), the cocatalyst comprises said different cation-generating cocatalyst.