Process of polymerization of propylene

Patent metadata

Field	Value
Publication number	US-9790299-B2
Application number	US-201314441380-A
Country	US
Kind code	B2
Filing date	Nov 6, 2013
Priority date	Nov 8, 2012
Publication date	Oct 17, 2017
Grant date	Oct 17, 2017

Abstract

The present disclosure provides a ziegler-natta pro-catalyst composition for the polymerization of propylene to produce polypropylene with reduced polymer-fines.

First claim

The invention claimed is:

1. A Ziegler-Natta pro-catalyst composition for the polymerization of propylene to produce polypropylene with reduced polymer-fines, comprising a reaction product of (i) at least one titanium compound of the molecular formula TiX n (OR 1 ) 4-n , wherein n is an integer from 0 to 4, X is halogen, R 1 is independently selected from the group consisting of C 1 to C 10 alkyl group; (ii) at least one magnesium containing precursor of molecular formula Mg(OR 2 )(OR 3 ), wherein R 2 and R 3 are identical or different, and independently selected from the group consisting of C 1 to C 10 alkyl groups, C 1 to C 6 aryl group and C 1 to C 10 alkylaryl group; and (iii) at least one internal electron donor selected from the group of compounds consisting of dicarboxylic acid ester, monocarboxylic acid ester, diethers, silyl esters, amides, carbonates, and succinates; said pro-catalyst composition containing iron ranging between about 50 ppm and 100 ppm.

2. The pro-catalyst composition as claimed in claim 1 , wherein the titanium compound is selected from the group consisting of tetravalent titanium halides and titanium alkoxides.

3. The pro-catalyst composition as claimed in claim 1 , wherein the titanium compound is titanium tetrachloride.

4. The pro-catalyst composition as claimed in claim 1 , wherein the magnesium containing precursor is selected from the group of compounds consisting of magnesium dialkoxides and magnesium diaryloxides.

5. The pro-catalyst composition as claimed in claim 1 , wherein the magnesium containing precursor is selected from the group consisting of magnesium methoxide, magnesium ethoxide, magnesium iso-propoxide, magnesium n-butoxide, magnesium phenoxide, and combinations thereof.

6. The pro-catalyst composition as claimed in claim 1 , wherein the internal electron donor is di-isobutyl phthalate.

7. A process for preparing a Ziegler-Natta pro-catalyst composition as claimed in claim 1 , said process comprising the following step;
reacting at least one titanium compound of molecular formula TiX n (OR 1 ) 4-n , wherein n is an integer from 0 to 4, X is halogen, R 1 is independently selected from the group consisting of C 1 to C 10 alkyl group with at least one magnesium containing precursor of molecular formula Mg(OR2)(OR3), wherein R 2 and R 3 are identical or different, and independently selected from the group consisting of C 1 to C 10 alkyl group, C 1 to C 6 aryl group and C 1 to C 10 alkylaryl group, and at least one internal electron donor selected from the group of compounds consisting of dicarboxylic acid esters, monocarboxylic acid ester, diethers, silyl esters, amides, carbonates, and succinates optionally in the presence of an inert hydrocarbon solvent.

8. The process as claimed in claim 7 , wherein the titanium compound is selected from the group consisting of tetravalent titanium halides and titanium alkoxides.

9. The process as claimed in claim 7 , wherein the magnesium containing precursor is selected from the group of compounds consisting of magnesium dialkoxides and magnesium diaryloxides.

10. The process as claimed in claim 7 , wherein the inert hydrocarbon solvent is selected from the group consisting of halohydrocarbons.

11. A catalyst composition with controlled particle size distribution and regular shape, comprising; (i) a pro-catalyst composition containing iron ranging between about 50 ppm and 100 ppm, as claimed in claim 1 ; (ii) trialkyl aluminum as a co-catalyst; and (iii) optionally, at least one external electron donor selected from the group of silanes, alkoxy silanes, alkyl silane, alkyl alkoxy silane, and aliphatic ester and aromatic ester.

12. The catalyst composition as claimed in claim 11 , wherein the co-catalyst and the pro-catalyst are present in the molar ratio between 1:30 and 1:100.

13. The catalyst composition as claimed in claim 11 , wherein the co-catalyst and the external electron donor are present in the molar ratio between 1:1 and 1:40.

14. A process for the polymerization of propylene in the presence of a catalyst composition containing iron ranging from between about 50 ppm and 100 ppm as claimed in claim 11 , said process comprises contacting propylene monomers with the catalyst composition, in a gas-phase fluidized bed reactor, under the polymerization condition of temperature ranging between 65° C. and 75° C. and pressure ranging between 25 kg/cm 2 and 35 kg/cm 2 , to obtain polypropylene having controlled particle size distribution and reduced polymer-fines.

15. The process as claimed in claim 14 , wherein the co-catalyst and the pro-catalyst are present in the molar ratio between 1:30 and 1:100.

16. The process as claimed in claim 14 , wherein the co-catalyst and the external electron donor are present in the molar ratio between 1:1 and 1:40.

17. The process as claimed in claim 14 wherein the polypropylene is characterized by having average particle size between 350 and 700 micron and bulk density between 0.3 and 0.6 gm/cc.

18. The process as claimed in claim 14 , wherein the amount of polymer fines having average particle size less than 100 μm is not more than 10%.

Assignees

• Reliance Ind Ltd

Inventors

• Thakare Yogeshwar Narayanrao
• Gupta Virendrakumar

Classifications

• C08F110/06 Primary

  Propene · CPC title

• C08F2410/01

  Additive used together with the catalyst, excluding compounds containing Al or B · CPC title

• C08F2410/04

  Dual catalyst, i.e. use of two different catalysts, where none of the catalysts is a metallocene · CPC title

• C08F2500/24

  Polymer with special particle form or size · CPC title

• C08F4/6548

  magnesium or compounds thereof, not provided for in C08F4/6543 or C08F4/6546 · CPC title