High melting thermoplastic elastomeric alpha-olefin polymers (PRE/EPE effect) and catalysts therefor

This invention relates generally to processes for production of -olefin polymers using unbridged fluxional metallocenes, primarily substituted aryl indenyl metallocenes, and more particularly to use of unbridged, fluxional, cyclopentadienyl or indenyl metallocene catalysts and catalyst systems in methods of production of high melting point olefin homo- and co-polymers, particularly elastomeric crystalline and amorphous block homo- and co-polymers of alpha olefins. More specifically, the invention is directed to: (1) the discovery and catalytic process use of a Polymerization Rate-Enhancement effect (PRE effect) in polymerization processes which involve the addition of minor amounts of ethylene to the polymerization system to produce polymers having properties ranging from crystalline thermoplastics to high melting point thermoplastic elastomers to amorphous gum elastomers, and methods for increasing polymerization production rates and polymer molecular weight; (2) the discovery and catalytic process use of an Elastomeric Property-Enhancement effect (EPE effect) in which small quantities of ethylene added to the polymerization system activates selected metallocene catalyst systems, which otherwise do not produce elastomeric polymers, to produce elastomeric polymers; and (3) novel substituted aryl indenyl metallocene catalysts. This invention relates generally to low ethylene insertions into I-olefin polymers and processes for production of such polymers using unbridged fluxional metallocenes, primarily substituted aryl indenyl metallocenes, and more particularly to use of unbridged, fluxional, cyclopentadienyl or indenyl metallocene catalyst systems in methods of production of high melting point I-olefin homo- and co-polymers, particularly elastomeric crystalline and amorphous block homo- and co-polymers of I-olefins. The activity of fluxional unbridged metallocene polymerization catalysts containing at least one 2-arylindene ligand is increased 10× or more by the addition of small (typically 0.1-10 wt. %) amounts of ethylene to the polymerization system, which increase is termed the Polymerization Rate-Enhancement effect (PRE), which is measured in terms of an Ethylene Enhancement Factor (EEF) as a dimensionless ratio in the range of from about 1.1 to about 10 or above. The amount of ethylene included in the reaction system can be selected and controlled to be so small as to result in essentially minimal (