Patent EA-002052-B1 (EA)
Title: Process for preparing ziegler-natta catalyst for alpha olefins polymerization in solution
Inventor: JABER ISAM
IPC: C08F10/00
Filed: 1999-04-06
Abstract: 1. A process to prepare a catalyst for the solution polymerization of a mixture of one or more linear C2-12 alpha olefins at a temperature from 105 degree C to 320 degree C and a pressure from 4 to 20 MPa wherein said catalyst comprises: (i) a mixture of an trialkylaluminum compound of the formula (R<1>)3Al<1> and dialkylmagnesium (R<2>)2Mg wherein R<1> is a C1-10 alkyl radical and R<2> is a C1-10 alkyl radical in a molar ratio of Mg to Al<1> from 4:1 to 8:1; (ii) a halide of the formula R<3>X wherein R<3> is selected from the group consisting of C1-8 alkyl radicals and X is selected from the group consisting of chlorine and bromine; (iii) titanium tetrachloride; and (iv) an alkylaluminum alkoxide compound of the formula (R<4>)2Al<2>OR<5> wherein R<4> and R<5> are independently selected from the group consisting of C1-10 alkyl radicals, to provide a molar ratio of Mg:Ti from 4:1 to 8:1; a molar ratio of Al<1> to titanium tetrachloride from 0.9:1 to 1.5:1; a molar ratio of halide to Mg from 1.9:1 to 2.6:1; and a molar ratio of Al to titanium from 2:1 to 4:1 comprising mixing in an inert hydrocarbon solvent in a first reactor, at least the halide, the magnesium and one aluminum compound maintaining them at a temperature from 50 degree C to 100 degree C for a period of time from 2 to 30 minutes and adding the remaining catalyst component to the heat treated mixture or directly to the polymerization reactor. 2. The process according to Claim 1, wherein the mole ratio of Al<1> to Ti is from 1:1 to 1.3:1. 3. The process according to Claim 2, wherein the mole ratio of halide to Mg is from 1.9:1 to 2.5:1. 4. The process according to Claim 3, wherein the mole ratio of Mg to Al<1> is from 6:1 to 8:1. 5. The process according to Claim 4, wherein the mole ratio of Mg to Ti is from 6:1 to 8:1. 6. The process according to Claim 5, wherein the mole ratio of Al<1> to Ti is from 0.9:1 to 1.1:1. 7. The process according to Claim 6, wherein the mole ratio of Al<2> to Ti is from 3:1 to 4:1. 8. The process according to Claim 7, wherein the catalyst mixing temperature is from 60 degree C to 100 degree C. 9. The process according to Claim 8, wherein the catalyst mixing time in the first reactor is from 5 to 20 minutes. 10. The process according to Claim 9, wherein the titanium compound, the mixture of the Al<1> compound and the magnesium compound, and the halide compound, are initially mixed and heat treated. 11. The process according to Claim 10, wherein R<1>, R<3>, R<4> and R<5> are independently selected from the group consisting of C1-4 alkyl radicals. 12. The process according to Claim 11, wherein R<1> is an ethyl radical. 13. The process according to Claim 12, wherein R<2> is a C2-6 alkyl radical. 14. The process according to Claim 13, wherein R<3> is a tert-butyl radical. 15. The process according to Claim 14, wherein R<4> and R<5> are ethyl radicals. 16. The process according to Claim 10, wherein the Al<2> compound is added directly to the polymerization reactor. 17. The process according to Claim 10, wherein the Al<2> compound is added to the transfer between the first and second reactor. 18. The process according to Claim 15, wherein the Al<2> compound is added directly to the polymerization reactor. 19. The process according to Claim 15, wherein the Al<2> compound is added to the transfer between the first and second reactor. 20. The process according to Claim 9, wherein all of the catalyst components are mixed and heat treated in the first continuously stirred reactor. 21. The process according to Claim 20, wherein R<1> is an ethyl radical. 22. The process according to Claim 20, wherein R<2> is a C2-6 alkyl radical. 23. The process according to Claim 22, wherein R<3> is a tert-butyl radical. 24. The process according to Claim 23, wherein R<4> and R<5> are ethyl radicals.