Solid single site catalysts with high polymerisation activity
Process for the preparation of a solid catalyst system comprising the steps of preparing a liquid clathrate comprising a mixing of an aluminoxane, an aromatic compound and an organo-silicon compound, wherein the mol-ratio between the organo-silicon compound and aluminum of the aluminoxane is below 0.1, mixing said liquid clathrate with an organometallic compound obtaining a liquid mixture, and precipitating the solid catalyst system out of said liquid mixture by adding a saturated aliphatic compound to said mixture liquid.
1. A process for the preparation of a solid catalyst system (CS) comprising the steps of
(i) preparing a liquid clathrate (LC) comprising a mixing of an aluminoxane (A), an aromatic compound (AC) and an organo-silicon compound (OS), wherein the mol-ratio between the organo-silicon compound (OS) and aluminum (Al) of the aluminoxane (A) [(OS)/(Al)] is equal or below 0.1,
(ii) mixing said liquid clathrate (LC) with an organometallic compound (C),
(iii) obtaining a liquid mixture (MI), wherein the liquid mixture (MI) is homogeneous, precipitating the solid catalyst system (CS) out of said liquid mixture (MI) by adding a saturated aliphatic compound to said liquid mixture (MI), and
(iv) optionally recovering particles of the solid catalyst system (CS),
wherein during the process no carrier material is added.
2. The process according to claim 1 , wherein said organometallic compound (C) is of formula (I)
(L) m R n MX q (I)
wherein
“M” is a transition metal (M) of group 3 to 10 of the Periodic Table (IUPAC 2007), each “X” is independently a mono anionic ligand, like a σ-ligand,
each “L” is independently an organic ligand which coordinates to the transition metal “M”,
“R” is a bridging group linking said organic ligands (L),
“m” is 1, 2 or 3,
“n” is 0, 1 or 2,
“q” is 1, 2 or 3, and
m+q is equal to the valency of the transition metal (M).
3. The process according to claim 1 , wherein the mol-ratio between the aluminum (Al) of the aluminoxane (A) and the transition metal (M) of the organometallic compound (C) [(Al)/(M)] is in the range of 50 to 600.
4. The process according to claim 1 , wherein the organo-silicon compound (OS) is selected from the group consisting of octamethyltrisiloxane, decamethyltetrasiloxane, octamethylcyclotetrasiloxane, methoxytrimethylsilane, tetraethoxysilane and 1,1,1,3,5,5,5-heptamethyl-3-phenyltrisiloxane.
5. The process according to claim 1 , wherein
(a) the aromatic compound (AC) is toluene;
and/or
(b) the saturated aliphatic compound is selected from the group consisting of n-pentane, n-hexane, n-heptane, n-octane, and mixtures thereof.
6. The process according to claim 1 , wherein
(a) step (i) is accomplished at a temperature in the range of −20 to 70° C., and
(b) step (ii) is accomplished at a temperature in the range of 0 to 50° C.
7. The process according to claim 1 , wherein the organometallic compound (C) is of formula (II)
(L) 2 RMX 2 (II)
wherein
“M” is zirconium (Zr) or hafnium (Hf),
each “X” is independently selected from halogen, C 1 to C 6 alkyl, C 5 to C 6 cycloalkyl, C 1 to C 6 alkoxy, phenyl and benzyl groups,
each “L” is independently a cyclopentadienyl, indenyl, tetrahydroindenyl, or fluorenyl, which is independently substituted or unsubstituted, which optionally contains one or more heteroatoms selected from groups 14 to 16 and/or is optionally substituted by halogen atom(s), and
“R” is a divalent bridge selected from —R′ 2 C—, —R′ 2 Si—, wherein each R′ is independently a hydrogen atom, C 1 to C 20 alkyl, or C 3 to C 10 cycloalkyl.
8. The process according to claim 2 , wherein the mol-ratio between the aluminum (Al) of the aluminoxane (A) and the transition metal (M) of the organometallic compound (C) [(Al)/(M)] is in the range of 50 to 600.
9. The process according to claim 2 , wherein the organo-silicon compound (OS) is selected from the group consisting of octamethyltrisiloxane, decamethyltetrasiloxane, octamethylcyclotetrasiloxane, methoxytrimethylsilane, tetraethoxysilane and 1,1,1,3,5,5,5-heptamethyl-3-phenyltrisiloxane.
10. The process according to claim 2 , wherein
(a) the aromatic compound (AC) is toluene;
and/or
(b) the saturated aliphatic compound is selected from the group consisting of n-pentane, n-hexane, n-heptane, n-octane, and mixtures thereof.
11. The process according to claim 2 , wherein
(a) step (i) is accomplished at a temperature in the range of −20 to 70° C.,
and
(b) step (ii) is accomplished at a temperature in the range of 0 to 50° C.
12. The process according to claim 2 , wherein the organometallic compound (C) is of formula (II)
(L) 2 RMX 2 (II)
wherein
“M” is zirconium (Zr) or hafnium (Hf),
each “X” is independently selected from halogen, C 1 to C 6 alkyl, C 5 to C 6 cycloalkyl, C 1 to C 6 alkoxy, phenyl and benzyl groups,
each “L” is independently a cyclopentadienyl, indenyl, tetrahydroindenyl, or fluorenyl, which is independently substituted or unsubstituted, which optionally contains one or more heteroatoms selected from groups 14 to 16 and/or is optionally substituted by halogen atom(s), and
“R” is a divalent bridge selected from —R′ 2 C—, —R′ 2 Si—, wherein each R′ is independently a hydrogen atom, C 1 to C 20 alkyl, or C 3 to C 10 cycloalkyl.