Polymerisation process and catalyst

1. A process for the polymerization of at least one olefin comprising reacting said at least one olefin with a catalyst comprising:

(i) a metallocene complex comprising at least two cyclopentadienyl type ligands;

(ii) a boron cocatalyst; and

(iii) an aluminoxane cocatalyst;

said catalyst being in solid form—and free from an external carrier.

2. A process for the preparation of a propylene and ethylene copolymer comprising copolymerizing propylene and ethylene in the presence of a catalyst comprising:

(i)a metallocene complex of a group (IV) metal comprising at least two cyclopentadienyl type ligands;

(ii) a boron cocatalyst; and

(iii) an aluminoxane cocatalyst;

said catalyst being in solid form and free from an external carrier;

wherein the productivity of the process is at least 60 kg polymer/g catalyst.

3. A process for the preparation of a propylene and ethylene copolymer comprising copolymerizing propylene and ethylene in the presence of a catalyst comprising:

(i)a metallocene complex of a group (IV) metal comprising at least two cyclopentadienyl type ligands;

(ii) a boron cocatalyst; and

(iii) an aluminoxane cocatalyst;

said catalyst being in solid form and free from an external carrier; wherein the catalyst is obtained by a process comprising

(a) forming a liquid/liquid emulsion system, said liquid/liquid emulsion system comprising a solution of components (i) to (iii) dispersed in a solvent so as to form dispersed droplets;

(b) forming solid particles by solidifying said dispersed droplets; and

(c) prepolymerizing the solid particles from step (b) with at least one C 2-10 alpha-olefin monomer and optionally one or more different C 2 -C 10 alpha-olefin comonomers.

4. The process according to claim 1 , wherein the catalyst is prepared by a process comprising

(a) forming a liquid/liquid emulsion system, said liquid/liquid emulsion system comprising a solution of the components (i) to (iii) dispersed in a solvent so as to form dispersed droplets; and

(b) forming solid particles by solidifying said dispersed droplets.

5. The process according to claim 4 wherein the solid particles are prepolymerized in a step (c).

6. The process according to claim 1 , wherein the boron cocatalyst is a borate-type cocatalyst.

7. The process according to claim 1 , wherein said metallocene complex is of formula (II):

wherein

M is a group (IV) metal;

each X is a sigma ligand;

L is a divalent bridge selected from —R′ 2 C—, —R′ 2 C—CR′ 2 —, —R′ 2 Si—, —R′ 2 Si—SiR′ 2 —, —R′ 2 Ge—, wherein each R′ is independently a hydrogen atom, C 1 -C 20 -hydrocarbyl, and tri(C 1 -C 20 -alkyl)silyl;

R 2 and R 2′ are each independently H, or a C 1 -C 20 hydrocarbyl radical optionally containing one or more heteroatoms from groups 14-16;

R 3 and R 3′ are each independently H or a C 1 -C 20 hydrocarbyl radical optionally containing one or more heteroatoms from groups 14-16;

R 4 or R 4′ are each independently an aryl or heteroaryl group having up to 20 carbon atoms optionally substituted by one or more groups R 1 ;

R 5 and R 5′ are each independently H or a C 1-20 hydrocarbyl group optionally containing one or more heteroatoms from groups 14-16 and optionally substituted by one or more halo atoms;

R 6 and R 6′ are each independently hydrogen or a C 1-20 hydrocarbyl group optionally containing one or more heteroatoms from groups 14-16; or R 5 and R 6 and/or R 5′ and R 6′ taken together form a 4-7 membered ring condensed to the benzene ring of the indenyl moiety, said ring optionally containing heteroatoms from groups 14-16, each atom forming said ring being optionally substituted with at least one R 1 radical;

R 7 and R 7′ are each independently hydrogen or C 1-20 hydrocarbyl group optionally containing one or more heteroatoms from groups 14-16; and

R 1 is a C 1-20 hydrocarbyl group or two R 1 groups on adjacent carbon atoms taken together can form a fused 5 or 6 membered non aromatic ring with the R 4 or R 4′ group, said ring being itself optionally substituted with one or more R 1 groups.

8. The process according to claim 1 , wherein said metallocene complex is of formula (III)

wherein M is Hf or Zr;

each X is independently a hydrogen atom, a halogen atom, C 1-6 alkoxy group, C 1-6 alkyl, phenyl or benzyl group;

L is a divalent bridge selected from —R′ 2 C— and —R′ 2 Si— wherein each R′ is independently a hydrogen atom, C 1-20 alkyl or C 3-10 cycloalkyl;

R 2 and R 2′ are each independently H, a linear C 1 -C 6 alkyl or branched C 4-10 -alkyl, especially methyl or isobutyl;

n is independently 0, 1 or 2;

R 1 is independently C 1-6 alkyl group;

R 5 and R 5′ are each independently H, phenyl, a C 1-10 alkyl group or OC 1-10 alkyl group;

R 6 and R 6′ are each independently hydrogen or a C 1-10 alkyl group; or R 5 and R 6 and/or R 5′ and R 6′ taken together form a 5-6 membered ring condensed to the benzene ring of the indenyl moiety being optionally substituted with one R 1 radical.

9. The process according to claim 1 , wherein said metallocene complex is of formula (IV)

wherein M is Hf or Zr;

each X is independently a hydrogen atom, a halogen atom, C 1-6 alkoxy group, C 1-6 alkyl, phenyl or benzyl group;

L is a divalent bridge selected from —R′ 2 C— and —R′ 2 Si— wherein each R′ is independently a hydrogen atom, C 1-20 alkyl or C 3-10 cycloalkyl;

R 2 and R 2′ are each independently C 1-6 -alkyl;

n is independently 0, 1 or 2;

R 1 is independently C 3-6 alkyl group;

R 5 and R 5′ are each independently H, C 1-6 alkyl group or OC 1-6 alkyl group;

R 6 and R 6′ are each independently a H, C 1-6 alkyl group; or R 5 and R 6 and/or R 5′ and R 6′ taken together form an unsubstituted 5 membered ring condensed to the benzene ring of the indenyl moiety.

10. The process according to claim 1 , wherein said aluminoxane is MAO.

11. The process according to claim 1 , wherein said boron cocatalyst comprises an anion of formula:

(Z) 4 B −   (V)

where Z is an optionally substituted phenyl derivative, said substituent being a C 1-6 alkyl group, haloC 1-6 -alkyl or halo group.

12. The process according to claim 1 , wherein in polymerization, said catalyst exhibits 20% or higher activity relative to an otherwise identical catalyst made using MAO alone under the same polymerization conditions.

13. The process according to claim 11 , wherein Z is selected from a triphenylcarbeniumtetrakis(pentafluorophenyl)borate, a N,N-dimethylcyclohexylammoniumtetrakis(pentafluorophenyl)borate, a N,N-dimethylbenzylammoniumtetrakis(pentafluorophenyl)borate, and a (N,N-dimethylaniliniumtetrakis(pentafluorophenyl)borate).

14. The process according to claim 1 , wherein said metallocene complex is of formula (II):

wherein

M is a group (IV) metal;

each X is a sigma ligand;

L is a divalent bridge selected from —R′ 2 C—, —R′ 2 C—CR′ 2 —, —R′ 2 Si—, —R′ 2 Si—SiR′ 2 —, —R′ 2 Ge—, wherein each R′ is independently a hydrogen atom, C 1 -C 20 -hydrocarbyl, and tri(C 1 -C 20 -alkyl)silyl;

R 2 and R 2′ are each independently H, or a C 1 -C 20 hydrocarbyl radical optionally containing one or more heteroatoms from groups 14-16;

R 3 and R 3′ are each independently H or a C 1 -C 20 hydrocarbyl radical optionally containing one or more heteroatoms from groups 14-16;

R 4 or R 4′ are each independently an aryl or heteroaryl group having up to 20 carbon atoms optionally substituted by one or more groups R 1 ;

R 5 and R 5′ are each independently H or a C 1-20 hydrocarbyl group optionally containing one or more heteroatoms from groups 14-16 and optionally substituted by one or more halo atoms;

R 6 and R 6′ are each independently hydrogen or a C 1-20 hydrocarbyl group optionally containing one or more heteroatoms from groups 14-16;

R 7 and R 7′ are each independently hydrogen or C 1-20 hydrocarbyl group optionally containing one or more heteroatoms from groups 14-16; and

R 1 is a C 1-20 hydrocarbyl group or two R 1 groups on adjacent carbon atoms taken together can form a fused 5 or 6 membered non aromatic ring with the R 4 or R 4′ group, said ring being itself optionally substituted with one or more R 1 groups.