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US4525547A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for producing ethylene copolymer by gaseous phase copolymerization

Assignee: Mitsui Chemicals Inc
•
Filing: 1984-04-02
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Granted: 1985-06-25
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Expires: 2004-04-02
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Abstract

Abstract A process for producing an ethylene copolymer which comprises polymerizing a predominant amount of ethylene and a minor amount of an alpha-olefin having 4 to 10 carbon atoms in the gaseous phase in the presence of a catalyst composed of (A) a transition metal catalyst component and (B) an organometallic compound of a metal of Groups I to III of the periodic table; characterized in that the copolymerization is carried out under the following conditions (i) and (ii), (i) at least 1 mole, per mole of ethylene, of a gaseous saturated hydrocarbon having 3 to 6 carbon atoms is caused to be present in the gaseous phase copolymerization system, and (ii) the gaseous mixture containing the unreacted olefin which has been discharged from the gaseous phase copolymerization system is cooled to a temperature at which the mixture is not liquefied, and the cooled gaseous mixture is recycled to the gaseous phase copolymerization system.

Inventors

  • 👤 Akifumi Kato
  • 👤 Junichi Yoshida
  • 👤 Ryoichi Yamamoto

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 17:34
CPC Classifications
C; C08; C08F; C08F210/00; C08F210/16; Y; Y10; Y10S; Y10S526/00; Y10S526/901; Y10S526/903; Y10S526/904

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 195 words
In a gaseous phase polymerization process for producing an ethylene copolymer having a density of from about 0.923 to about 0.943 g/cc which comprises polymerizing a predominant amount of ethylene and a minor amount of an alpha-olefin having 4 to 10 carbon atoms at a temperature of from room temperature to about 130° C. and below the melting point of the copolymer formed and a pressure of from 1 to 100 kg/cm 2 .G in the presence of a catalyst composed of (A) a transition metal catalyst component and (B) an organometallic compound of a metal of Groups I to III of the periodic table; the improvement wherein the copolymerization is carried out under the following conditions (i) and (ii), (i) at least 1 mole, per mole of ethylene, of a gaseous saturated hydrocarbon having 3 to 6 carbon atoms is caused to be present in the gaseous phase copolymerization system, and (ii) the gaseous mixture containing the unreacted olefin which has been discharged from the gaseous phase copolymerization system is cooled to a temperature at which the mixture is not liquefied, and the cooled gaseous mixture is recycled to the gaseous phase copolymerization system.
Claim 2
Dependent Claim 195 words
In a gaseous phase polymerization process for producing an ethylene copolymer having a density of from about 0.923 to about 0.943 g/cc which comprises polymerizing a predominant amount of ethylene and a minor amount of an alpha-olefin having 4 to 10 carbon atoms at a temperature of from room temperature to about 130° C. and below the melting point of the copolymer formed and a pressure of from 1 to 100 kg/cm 2 .G in the presence of a catalyst composed of (A) a transition metal catalyst component and (B) an organometallic compound of a metal of Groups I to III of the periodic table; the improvement wherein the copolymerization is carried out under the following conditions (i) and (ii), (i) at least 1 mole, per mole of ethylene, of a gaseous saturated hydrocarbon having 3 to 6 carbon atoms is caused to be present in the gaseous phase copolymerization system, and (ii) the gaseous mixture containing the unreacted olefin which has been discharged from the gaseous phase copolymerization system is cooled to a temperature at which the mixture is not liquefied, and the cooled gaseous mixture is recycled to the gaseous phase copolymerization system.
Claim 3
Dependent Claim 29 words
The process of claim 1 wherein the saturated hydrocarbon has a different number of carbon atoms from the alpha-olefin having 4 to 10 carbon atoms used in the copolymerization.
Claim 4
Dependent Claim 29 words
The process of claim 1 wherein the saturated hydrocarbon has a smaller number of carbon atoms than the alpha-olefin having 4 to 10 carbon atoms used in the copolymerization.
Claim 5
Dependent Claim 16 words
The process of claim 1 wherein the mole ratio of ethylene to the alpha-olefin is 1:0.001-0.4.
Claim 6
Dependent Claim 23 words
The process of claim 1 wherein the mole ratio of ethylene to the saturated hydrocarbon having 3 to 6 carbon atoms is 1:1-100.

References Cited (Backward Citations)

US3912698A Cited
US3971768A Cited
US4129701A Cited
US4168356A Cited
US4258158A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-06-24 1988-12-24 1989-06-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-06-24 1992-12-24 1993-06-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-06-24 1996-12-24 1997-06-25 $7700.00 Window Closed / Lapsed

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