Process for the preparation of ethylene polymers and products obtained therefrom

Claim 2

The process according to claim 1, wherein the metallocene compound is represented by the formula (I): wherein M is a metal selected from Ti, Zr and Hf; R¹, same or different, are C₁-C₂₀ alkyl radicals, C₃-C₂₀ cycloalkyl radicals, C₂-C₂₀ alkenyl radicals, C₆-C₂₀ aryl radicals, C₇-C₂₀ alkylaryl radicals or C₇-C₂₀ arylalkyl radicals and can contain Si or Ge atoms; R² and R³, same or different, are hydrogen atoms, C₁-C₂₀ alkyl radicals, C₃-C₂₀ cycloalkyl radicals, C₂-C₂₀ alkenyl radicals, C₆-C₂₀ aryl radicals, C₇-C₂₀ alkylaryl radicals or C₇-C₂₀ arylalkyl radicals and can contain Si or Ge atoms; R⁴ is a divalent group selected from (CR⁵₂) n , (SiR⁵₂) n , (GeR⁵₂) n , NR⁵ or PR⁵, wherein R⁵, same or different, are C₁-C₂₀ alkyl radicals, C₃-C₂₀ cycloalkyl radicals, C₂-C₂₀ alkenyl radicals, C₆-C₂₀ aryl radicals, C₇-C₂₀ alkylaryl radicals or C₇-C₂₀ arylalkyl radicals, and when R⁴ is (CR⁵₂) n , (SiR⁵₂) n , (GeR⁵₂) n , two substituents R⁵ on the same carbon, silicium or germanium atom can form a cycle comprising from 3 to 8 atoms; n is an integer comprised between 1 and 4, preferably being 1 or 2, X¹ and X², same or different, are hydrogen atoms, halogen atoms, R⁶, OR⁶, SR⁶, NR⁶₂ or PR⁶₂, wherein substituents R⁶, same or different from each other, are C₁-C₂₀ alkyl radicals, C₃-C₂₀ cycloalkyl radicals, C₂-C₂₀ alkenyl radicals, C₆-C₂₀ aryl radicals, C₇-C₂₀ alkylaryl radicals or C₇-C₂₀ arylalkyl radicals and can contain Si or Ge atoms; and wherein R¹ and R² on the same cyclopentadienyl ligand can form a cycle comprising from 5 to 8 carbon atoms.

Claim 3

The process according to claim 2, wherein the metallocene compound is represented by the formula (II): wherein M, R³, R⁴, X¹ and X² are defined as in claim 2; R⁷, same or different, are hydrogen atoms, C₁-C₁₀ alkyl radicals, C₃-C₁₀ cycloalkyl radicals, C₂-C₁₀ alkenyl radicals, C₆-C₁₀ alkylaryl radicals or C₇-C₁₀ arylalkyl radicals and can contain Si or Ge atoms; p and q, same or different, are integers comprised between 1 and 4; and wherein two adjacent substituents R⁷ on the same ligand can form a cycle comprising from 5 to 8 carbon atoms.

Claim 4

The process according to claim 3, wherein the metallocene is the ethylene-bis(4,7-dimethyl-1-indenyl)zirconium dichloride.

Claim 5

The process according to claim 2, wherein the metallocene compound is represented by the formula (III): wherein M, R³, R⁴, X¹ and X² are defined as in claim 2; R⁷, same or different, are hydrogen atoms, C₁-C₁₀ alkyl radicals, C₃-C₁₀ cycloalkyl radicals, C₂-C₁₀ alkenyl radicals, C₆-C₁₀ alkylaryl radicals or C₇-C₁₀ arylalkyl radicals and can contain Si or Ge atoms; p and q, same or different, are integers comprised between 1 and 4; and wherein two adjacent substituents R⁷ on the same ligand can form a cycle comprising from 5 to 8 carbon atoms.

Claim 6

The process according to any of claims from 1 to 5, wherein the catalyst comprises at least one compound selected between the organometallic compounds of aluminum, and the compounds able to form a metallocene alkyl cation.

Claim 7

The process according to claim 6, wherein the organometallic compound of aluminum is a linear, branched or cyclic alumoxane, containing at least one group of the type (IV): wherein R⁸, same or different, are R⁹ or a group -O-Al(R⁸)₂ and, optionally, some R⁸ can be halogen atoms, R⁹ being defined as R¹.

Claim 8

The process according to any of claims from 1 to 7, wherein the polymerization reaction of ethylene is carried out in the presence of at least one olefin selected from the alpha-olefins of the formula (IX): CH₂=CH-R   (IX) wherein R is an alkyl radical containing from 1 to 20 carbon atoms, and the cycloolefins.

Claim 9

The process according to claim 8, wherein the olefin is selected from the alpha-olefins of the formula (IX) wherein R is an alkyl radical containing from 1 to 10 carbon atoms, to obtain an elastomeric copolymer of ethylene.

Claim 10

The process according to claim 9, wherein the polymerization is carried out in the presence of minor amounts of a polyene.

Claim 11

An elastomeric copolymer of ethylene with propylene and, optionally, one or more polyenes, having content of units deriving from ethylene comprised between about 35% and 85% by moles, content of units deriving from propylene comprised between about 10% and 60% by moles and content of units deriving from one or more polyenes comprised between 0 and 5% by moles, having the following characteristics: - content of propylene units in form of triads comprised between 0% and 8%; - less than 50% of the above mentioned propylene triads having isotactic structure; - product of the reactivity ratios r₁.r₂ lower than 0.5.

Claim 12

The elastomeric copolymer of ethylene according to claim 11, having intrinsic viscosity higher than 2.0 dl/g.

Claim 13

An elastomeric copolymer of ethylene with 1-butene and, optionally, one or more polyenes, having content of units deriving from ethylene comprised between about 35% and 85% by moles, content of units deriving from 1-butene comprised between about 10% and 60% by moles and content of units deriving from one or more polyenes comprised between 0 and 5% by moles, having the following characteristics: - content of 1-butene units in form of triads equal to 0; - product of the reactivity ratios r₁.r₂ higher than 0.1; - less than 2% of the CH₂ groups in the polymeric chain contained in sequences (CH₂) n comprised between two tertiary carbon atoms, wherein n is an even number.

Claim 14

An elastomeric copolymer of ethylene with at least one α-olefin of the formula (IX): CH₂=CH-R   (IX) wherein R is an alkyl radical containing from 1 to 10 carbon atoms, and at least one polyene, having content of units deriving from ethylene comprised between about 35% and 85% by moles, content of units deriving from α-olefins comprised between about 10% and 60% by moles and content of units deriving from polyenes comprised between 0 and 5% by moles, having the following characteristics: - intrinsic viscosity higher than 6.0 dl/g; - less than 2% of the CH₂ groups in the polymeric chain contained in sequences (CH₂) n comprised between two tertiary carbon atoms, wherein n is an even number.

Claim 15

The elastomeric copolymer of ethylene according to claim 14, wherein the α-olefin is propylene.

Claim 16

A stereorigid metallocene compound of a transition metal belonging to the Group IIIb, IVb, Vb, VIb or of Lanthanides of the Periodic Table of the Elements, having two substituted cyclopentadienyl ligands bridge joined between them, characterized in that it is substantially in its meso isomeric form.

Claim 17

Ethylene-bis(4,7-dimethyl-1-indenyl)zirconium dichloride substantially in its meso isomeric form.