Ziegler-Natta catalyst for high temperature polymerization

• US 9,481,748 B2
• Filed: 08/12/2014
• Issued: 11/01/2016
• Est. Priority Date: 08/12/2014
• Status: Active Grant

• Current Assignee: Nova Chemicals
• Original Assignee: Nova Chemicals
• Inventors: Wang, Qinyan, Ouskine, Helena, Aiffa, Mohamed, Baltimore, Amy, Severin, Holly, Dewit, Perry, Clemens, Steven, Van Asseldonk, Lawrence Martin Josef, Jaber, Isam
• Primary Examiner(s): Choi, Ling
• Assistant Examiner(s): Branch, Catherine S
• Application Number:
  US14/457,565
• Publication Number:
  US 20160046745A1
• Time in Patent Office: 812 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: C08F 10/02 Ethene
• CPC Class Codes: C08F 2/001 Multistage polymerisation processes characterised by a change in reactor conditions without deactivating the intermediate polymer C08F295/00, C08F297/00 take precedence
• CPC Class Codes: C08F 210/14 Monomers containing five or more carbon atoms
• CPC Class Codes: C08F 210/16 Copolymers of ethene with alpha-alkenes, e.g. EP rubbers
• CPC Class Codes: C08F 2500/03 Narrow molecular weight distribution, i.e. Mw/Mn < 3
• CPC Class Codes: C08F 2500/12 Melt flow index or melt flow ratio
• CPC Class Codes: C08F 2500/26 Use as polymer for film forming
• CPC Class Codes: C08F 4/6543 halides of magnesium
• CPC Class Codes: C08F 4/6546 organo-magnesium compounds
• CPC Class Codes: C08F 4/6555 and magnesium or compounds thereof
• CPC Class Codes: C08J 2323/08 Copolymers of ethene C08J2323/16 takes precedence
• CPC Class Codes: C08J 5/00 Manufacture of articles or shaped materials containing macromolecular substances manufacture of semi-permeable membranes B01D67/00 - B01D71/00

Abstract

The various embodiments of the invention provide, a magnesium titanium polymerization procatalyst, methods for making and using the same.

Claims

1. A procatalyst for polymerization of ethylene and α

-olefins on a delta form MgCl₂ support comprising a Ti³⁺ complex of the formula TiCl₃*[[R⁴]_a[R⁵O]_bAlX_3-c]_d

wherein

a is 0 to 1;

b is 0 to 1;

c=a+b;

d is from about 0.33 to about 1.0;

each R⁴ and R⁵ is independently selected from C_1-8 alkyl radicals;

each X is independently selected from the halogen radicals;

the Mg/Ti molar ratio is from about 5 to about 10;

and further wherein at least 60% of the total Ti present is in the Ti³⁺ oxidation state.

2. The procatalyst of claim 1, wherein X is Cl.

3. The procatalyst of claim 1, wherein a is 0 and b is 0.

4. The procatalyst of claim 1, wherein a is 0 and b is 1.

5. The procatalyst of claim 1, wherein a is 1 and b is 0.

6. The procatalyst of claim 1, wherein each R⁵ is ethyl.

7. The procatalyst of claim 1, wherein the Mg/Ti ratio is from about 5 to about 8.

8. The procatalyst of claim 1, wherein the Ti³⁺ complex is TiCl₃*[OEtAlCl₂]_d, and the Mg/Ti molar ratio is from about 5 to about 8.

9. The procatalyst of claim 1, wherein the Ti³⁺ complex is TiCl₃*[ClAlCl₂]_d, and the Mg/Ti molar ratio is from about 5 to about 8.

10. The procatalyst of claim 1, wherein the EPR spectrum and its simulation of the procatalyst has a characteristic g value of 1.950.

11. The procatalyst of claim 1, wherein electron paramagnetic resonance (EPR) indicates the presence of a species C, wherein the species C is associated with a tetrahedral Ti³⁺ species and wherein species C is about 0.2% or more of the Ti³⁺ species detected in the EPR spectra.

12. The procatalyst of claim 1, wherein electron paramagnetic resonance (EPR) indicates the presence of a species C, wherein the species C is associated with a tetrahedral Ti³⁺ species and wherein species C is about 0.3% to about 1% of the Ti³⁺ species detected in the EPR spectra.

13. A process to prepare an olefin polymerization procatalyst comprising a Ti³⁺ complex, said process comprising:

a) forming a delta form MgCl₂ species by combining

i) R₂Mg in a solvent selected from C_5-12 alkanes, and

ii) reactive organic chloride or HCl;

wherein each R is independently selected from C_2-8 alkyl radicals,

and wherein the mole ratio of added Cl and Mg is from about 2.0 to about 3.0;

b) adding to said delta form MgCl₂ species prepared in step a) either

i) R¹_xAlX_3-x and a tetravalent titanium compound in any order or at the same time,

wherein the AIM molar ratio is from about 3 to about 10;

or

ii) an aluminum alkyl halide of the formula R¹_xAlX_3-x first, a tetravalent titanium compound second, followed by an alkyl aluminum alkoxide of the formula R⁴_yAlOR⁵_3-y, wherein the Al/Ti molar ratio when measuring Al supplied from R¹_xAlX_3-x only is from about 0.7 to about 2 and the Al/Ti molar ratio when measuring Al supplied from R⁴_yAlOR⁵_3-y is from about 1 to about 2;

and further wherein

the Mg/Ti molar ratio is from about 5 to about 10;

x is 1 or 2;

y is 1 or 2;

each R¹ is independently selected from C_1-8 alkyl radicals;

the tetravalent titanium compound is selected from TiR²X₃, Ti(OR³)X₃, TiX₄, and mixtures thereof;

each X is independently selected from the halogen radicals;

each R² is independently selected from C_1-8 alkyl radicals and benzyl; and

each R³, R⁴ and R⁵ are independently selected from C_1-8 alkyl radicals.

14. The process of claim 13, wherein the reactive organic chloride is tertiary-butylchloride (tBuCl).

15. The process of claim 13, wherein step a) is performed at a temperature between about 20°

C. and about 160°

C.

16. The process of claim 13, wherein step b) or c) is performed at a temperature between about 40°

C. and 90°

C.

17. The process of claim 13, wherein R₂Mg is selected from butylethyl magnesium (BEM), dibutyl magnesium, and butyloctyl magnesium (BOM).

18. The process of claim 13, wherein the solvent is decane.

19. The process of claim 13, wherein the Cl/Mg mole ratio is from about 2.15 to about 2.5.

20. The process of claim 13, wherein R¹_xAlX_3-x is selected from isobutylaluminum dichloride (IBADC), ethylaluminumdichloride.

21. The process of claim 13, wherein the tetravalent titanium compound is TiCl₄.

22. The process of claim 13, wherein R⁴_yAlOR⁵_3-y is diethylaluminumethoxide.

23. A procatalyst product comprising a Ti³⁺ complex prepared by the process of claim 13.

24. A solution olefin polymerization process comprising

i) adding to one or more continuous stirred tank reactor (CSTR), optionally followed by a tubular reactor, either in series or parallel, a solvent selected from C_5-12 alkanes, or mixtures thereof, and a procatalyst for polymerization on a delta form MgCl₂ support comprising a Ti³⁺ complex of the formula TiCl₃*[[R⁴]_a[R⁵O]_bAlX_3-c]_d

wherein

a is 0 to 1;

b is 0 to 1;

c=a+b;

d is from 0.33 to 1.0;

each R⁴ and R⁵ is independently selected from C_1-8 alkyl radicals;

each X is independently selected from the halogen radicals;

wherein at least 60% of the total Ti present is in the Ti³⁺ oxidation state;

ii) adding ethylene, hydrogen and optionally one or more comonomers selected from C_3-8 comonomers to the reactor; and

iii) adding an aluminum alkyl activator to the reactor in a molar ratio of about 1 to about 10 relative to the amount of procatalyst.

25. The polymerization process of claim 24, wherein the activator is an aluminum alkyl activator selected from diethylaluminumethoxide and trialkyl aluminum compounds, and MAO.

26. The polymerization process of claim 24, wherein the solvent is isohexane or decane.

27. The polymerization process of claim 24, wherein the polymerization temperature is at least about 240°

C.

28. The polymerization process of claim 24, wherein the polymerization results in a polymer having the same density but where the process uses at least about 10% less comonomer feed compared to a polymerization process using a procatalyst for polymerization that contains substantially no tetrahedral Ti³⁺ species.

29. The polymerization process of claim 24, wherein the polymerization results in a polymer with the same density but with a higher Mw at any polymerization temperature than the Mw obtained for a polymer prepared using a procatalyst for polymerization that contains substantially no tetrahedral Ti³⁺ species.

30. The polymerization process of claim 24, wherein the reactor hold-up time is from about 30 seconds to about 5 minutes.