Supported Ziegler Natta procatalyst for ethylene polymerisation

1. Supported Ziegler-Natta procatalyst for ethylene polymerisation, comprising:

(i) a procatalyst that includes

a) a Group 1 to 3 metal of the periodic table, in the range of 6.5 to 18 wt. %,

b) a Group 13 or 14 metal of the periodic table, in the range of 0.3 to 3.5 wt. %,

c) an internal donor selected from bi-(oxygen containing ring)

compounds of formula (I):

X is C or Si,

each R 1 is the same or different and is hydrogen, a linear or branched C 1 to C 8 -alkyl group, or a C 3 -alkylene group,

and each R 2 to R 5 are the same or different and are hydrogen,

a linear or branched C 1 to C 8 -alkyl, or a C 3 -C 8 -alkylene group,

whereby two or more of R 1 to R 5 optionally form a ring,

n is the same for both oxygen-containing rings and is 1 or 2,

whereby the two oxygen-containing rings are individually saturated or unsaturated,

or an isomer mixture therefrom, and

d) a Group 4 to 6 metal of the periodic table, in the range of 2.0 to 7.0 wt %; and

(ii) an inorganic support.

2. Supported Ziegler-Natta procatalyst according to claim 1 , wherein in formula (I) X is C, both R 1 are the same and are a linear C 1 -C 4 -alkyl, each R 2 to R 5 are the same or different and are H or a C 1 to C 2 alkyl, n is for both oxygen-containing rings 1 and both oxygen-containing rings are saturated.

3. Supported Ziegler-Natta procatalyst according to claim 1 wherein in formula (I) X is C, both R 1 are the same and are methyl, up to four of the residues R 2 to R 5 are methyl and the remaining residues are H, n is for both oxygen-containing rings 1 and both oxygen-containing rings are saturated.

4. Supported Ziegler-Natta procatalyst according to claim 1 , wherein the procatalyst is deposited on the inorganic support.

5. Supported Ziegler-Natta procatalyst according to claim 1 , wherein the inorganic support is silica or magnesium chloride.

6. Supported Ziegler-Natta procatalyst according to claim 1 , wherein the inorganic support is silica or magnesium chloride.

7. Process for preparing a supported procatalyst according to claim 1 comprising depositing on a particulate inorganic support:

a) a metal compound of Group 1 to 3, comprising a magnesium compound of formula Mg(OR 7 ) 2-n (R 6 )n (II), wherein each R 7 and R 6 is independently a C 1-20 alkyl group which may optionally be substituted with halogen and 0≤n<2

b) a metal compound of Group 13 or 14, comprising an Al compound having the formula Al(alkyl) x X 3-x (111), where alkyl is an alkyl group with 1 to 12 carbon atoms, X is halogen and 0≤x≤3,

c) an internal donor selected from bi-(oxygen containing ring) compounds of formula (I):

X is C or Si,

each R 1 is the same or different and is hydrogen, a linear or branched C 1 to C 8 -alkyl group, or a C 3 -C 8 -alkylene group, and each R 3 to R 5 are the same or different and are hydrogen, a linear or branched C 1 to C 8 -alkyl, or a C 3 -C 8 -alkylene group,

whereby two or more of R 1 to R 5 can form a ring,

n is the same for both oxygen-containing rings and can be 0, 1 or 2, whereby the two oxygen-containing rings can be individually saturated or unsaturated, and

d) a transition metal compound of Group 4 to 6, comprising a halogen-containing titanium compound of the formula X y Ti(OR 8 ) 4-y (IV), wherein R 8 is a C 2 -C 20 alkyl group, X is halogen and y is 1, 2, 3 or 4.

8. Process according to claim 7 , wherein the inorganic support is silica or magnesium chloride.

9. Process according to claim 7 , wherein procatalyst is prepared by:

contacting the inorganic support first with the Al compound having the formula Al(alkyl) x X 3-x (III), where alkyl is an alkyl group with 1 to 12 carbon atoms, X is halogen and 0≤x≤3 to give a first reaction product;

then the first reaction product is contacted with a magnesium compound of formula Mg(OR 7 ) 2-n (R 6 )n (II), wherein each R 7 and R 6 is independently a C 1-20 alkyl group which may optionally be substituted with halogen and 0≤n<2 to give a second reaction product;

the second reaction product is contacted with the halogencontaining titanium compound of the formula X y Ti(OR 8 ) 4-y (IV), wherein R 8 is a C 2 C 20 alkyl group, X is halogen and y is 1, 2, 3 or 4,

whereby the magnesium compound of formula Mg(OR 7 ) 2-n (R 6 ) n (II) is first contacted with the internal donor of the formula (I) or an isomer mixtures therefrom before contacting with the first reaction product.

10. Process according to claim 7 , wherein

procatalyst is prepared by:

contacting the inorganic support with the Al compound having the formula Al(alkyl) x X 3-x (III), where alkyl is an alkyl group with 1 to 12 carbon atoms, X is halogen and 0≤x≤3 and the magnesium compound of formula Mg(OR 7 ) 2-n (R 6 )n (II), wherein each R 7 and R 6 is independently a C 1-20 alkyl group which may optionally be substituted with halogen and 0≤n<2 in any order to form a first solid intermediate

and either contacting the first solid intermediate with the internal donor of the formula (I) or an isomer mixture therefrom and subsequently with the halogen-containing titanium compound of the formula X y Ti(OR 8 ) 4-y (IV), wherein R 8 is a C 2 -C 20 alkyl group, X is halogen and y is 1, 2, 3 or 4,

or contacting the first solid intermediate with the halogen-containing titanium compound of the formula X y Ti(OR 8 ) 4-y (IV), wherein R 8 is a C 2 -C 20 alkyl group, X is halogen and y is 1, 2, 3 or 4, and then with the internal donor of the formula (I) or an isomer mixture therefrom.

11. Process for preparing a supported procatalyst according to claim 1 comprising the steps of:

1) preparing a solid magnesium aluminium complex containing magnesium, halogen, aluminium and an internal donor of the formula (I) or an isomer

mixtures therefrom by

(a1) adding to a solution of a magnesium compound of the formula (II):

Mg(OR 7 ) 2-n (R 6 ) n , wherein each R 6 and R 7 independently represents a C 1 -C 20 alkyl group and 0≤n<2,

an internal donor of formula (I) or an isomer mixture therefrom and

(a2) contacting the solution of (a1) with a solution of a compound of formula (III):

Al(alkyl) x X 3-x , wherein each alkyl independently represents an alkyl of 1 to 6 carbon atoms; X is independently a halogen; 0≤x<3,

(a3) separating the solidified reaction product from the reaction mixture and optionally washing the product with a wash solution once up to 4 times,

2) subsequently treating said solid magnesium aluminium complex with a halogen-containing titanium compound of the formula X y Ti(OR 8 ) 4-y (IV), wherein R 8 is a C 2 -C 20 alkyl group, X is halogen and y is 1, 2, 3 or 4, and

3) optionally performing one to 4 washing steps and recovering the supported procatalyst.

12. Process for preparing a supported procatalyst according to claim 1 comprising the steps of:

1) preparing a solid magnesium aluminium complex containing magnesium, halogen, aluminium and an internal donor of the formula (I) or an isomer mixtures therefrom by

(b1) adding to a solution of a magnesium compound of the formula (II):

Mg(OR 7 ) 2-n (R 6 )n, wherein each R6 and R7 independently represents a C1-C20 alkyl group and 0≤n<2,

a solution of a compound of formula (Ill):

Al(alkyl) x X 3-x , wherein each alkyl independently represents an alkyl of 1 to 6 carbon atoms; X is independently a halogen; 0≤x<3,

(b2) separating the solidified reaction product from the reaction mixture and optionally washing the product with a wash solution,

whereby the internal donor is either first premixed with the solution of the compound of formula (III) or added after contacting the solution of a magnesium compound of the formula (II) with the solution of a compound of formula (III).