Preparation of ethylene copolymers in fluid bed reactor

• US 4,302,566 A
• Filed: 02/27/1979
• Issued: 11/24/1981
• Est. Priority Date: 03/31/1978
• Status: Expired due to Term

• Current Assignee: Union Carbide Corporation (Dow, Inc.)
• Original Assignee: Union Carbide Corporation (Dow, Inc.)
• Inventors: Jorgensen, Robert J., Wagner, Burkhard E., Friis, Nils, Karol, Frederick J., Fraser, William A., Goeke, George L.
• Primary Examiner(s): Michl, Paul R.
• Application Number:
  US06/014,414
• Time in Patent Office: 1,001 Days
• Field of Search: 526/124, 526/125, 526/348, 526/348.2, 526/348.3, 526/348.4, 526/348.5, 526/348.6, 526/348.7
• US Class Current: 526/124.6
• CPC Class Codes: C08F 2/34 Polymerisation in gaseous state
• CPC Class Codes: C08F 210/16 Copolymers of ethene with alpha-alkenes, e.g. EP rubbers
• CPC Class Codes: C08F 2410/01 Additive used together with the catalyst, excluding compounds containing Al or B
• CPC Class Codes: C08F 4/6425 containing magnesium

Abstract

Ethylene copolymers having a density of ≧0.91 to ≦0.96 and a melt flow ratio of ≧22 to ≦32 are readily produced in a low pressure gas phase process at a productivity of ≧50,000 pounds of polymer per pound of Ti with a particulate catalyst diluted with an inert carrier material and formed from selected organo aluminum compounds and a precursor composition of the formula:

Mg.sub.m Ti.sub.1 (OR).sub.n X.sub.p [ED].sub.q

wherein ED is a selected electron donor compound.

m is ≧0.5 to ≦56

n is 0 or 1

p is ≧6 to ≦116

q is ≧2 to ≦85

R is a C₁ to C₁₄ aliphatic or aromatic hydrocarbon radical, or COR'"'"' wherein R'"'"' is a C₁ to C₁₄ aliphatic or aromatic hydrocarbon radical, and

X is selected from the group consisting of Cl, Br, I, or mixtures thereof.

Claims

1. A continuous process for producing ethylene copolymer containing ≧

90 mol percent of ethylene and ≦

10 mol percent of one or more C₃ to C₈ alpha olefins with a Ti containing catalyst at a productivity of ≧

50,000 pounds of polymer per pound of Ti under a pressure of <

1000 psi in a gas phase fluid bed reaction

said polymer being produced in granular form and having a density of ≧

0.91 to ≦

0.96 and a melt flow ratio of ≧

22 to ≦

32,

which comprises copolymerizing ethylene with >

0 to 0.9 mols of one or more C₃ to C₈ α

olefin monomers per mol of ethylene at a temperature of about 30°

to 115°

C. by contacting the monomer charge with, in the presence of about 0 to 2.0 mol of hydrogen per mol of ethylene in a gas phase reaction zone, particles of a non-comminuted catalyst system comprising

an activated precursor composition wherein said precursor composition has the formula

space="preserve" listing-type="equation">Mg.sub.m Ti.sub.1 (OR).sub.n X.sub.p [ED].sub.q

wherein

m is ≧

0.5 to ≦

56

n is 0 or 1

p is ≧

6 to ≦

116

q is ≧

2 to ≦

85

R is a C₁ to C₁₄ aliphatic or aromatic hydrocarbon radical, or COR'"'"' wherein R'"'"' is a C₁ to C₁₄ aliphatic or aromatic hydrocarbon radical,

X is selected from the group consisting of Cl, Br, I or mixtures thereof,

ED is a liquid organic electron donor compound in which said precursor composition and the Ti and Mg components thereof are soluble and which is selected from the group consisting of alkyl esters of aliphatic and aromatic carboxylic acids, aliphatic ethers, cyclic ethers and aliphatic ketones,

said precursor composition being diluted with at least one solid inert carrier material and being either

completely activated, prior to the feeding of the activated precursor composition to said reaction zone with ≧

10 to ≦

400 mols of carrier absorbed activator compound per mol of titanium compound in said precursor composition so as to thereby prepare a solid dry catalyst composition without having to heat said catalyst composition above 50°

C., or

partially activated with >

0 to <

10 mols of activator compound per mol of titanium compound in said precursor composition prior to feeding of the activated precursor composition to said reaction zone and then being completely activated in said reaction zone with ≧

10 to ≦

400 mols of activator compound per mol of titanium compound in said precursor composition, and

said activator compound having the formula

space="preserve" listing-type="equation">Al(R").sub.c X'"'"'.sub.d H.sub.e

wherein X'"'"' is Cl or OR'"'"'", R" and R'"'"'" are the same or different and are C₁ to C₁₄ saturated hydrocarbon radicals

d is 0 to 1.5,

e is 0 or 1, and

c+d+e=3.

2. A process as in claim 1 in which a solution of said precursor composition is prepared by dissolving at least one magnesium compound and at least one titanium compound in said electron donor compound and by then recovering said precursor composition by precipitating or crystallizing it from said solution,

said magnesium compound having the structure

3. A process as in claim 2 in which said magnesium compound comprises MgCl₂.

4. A process as in claim 3 in which said electron donor compound comprises at least one ether.

5. A process as in claim 4 in which said electron donor compound comprises tetrahydrofuran.

6. A process as in claim 4 in which said titanium compound comprises TiCl₄.

8. A process as in claim 1 in which said diluted precursor composition is partially activated with >

0 to <

10 mols of activator compound per mol of titanium in said precursor composition prior to the introduction of said precursor composition into said reaction zone.

9. A process as in claim 1 which is conducted under a mass gas flow rate of about 1.5 to 10 times G_mf.

10. A process as in claim 9 which is conducted at a productivity of ≧

100,000 pounds of polymer per pound of Ti.

11. A process as in claim 1 in which ethylene is copolymerized with propylene.

12. A process as in claim 1 in which ethylene is copolymerized with butene-1.

7. A process as in clam 6 in which said inert carrier material comprises silica.