Patent US4742117A successfully refreshed from Google Patents.
Patent US3655238A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4085266A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for the high pressure production of polyethylene

Assignee: Sumitomo Chemical Co Ltd
•
Filing: 1977-06-13
•
Granted: 1978-04-18
•
Expires: 1997-06-13
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract In a process for polymerizing ethylene in a two-zone autoclave reactor comprising a top reaction zone and a bottom reaction zone which process comprises polymerizing ethylene in said top reaction zone at 130° to 200° C and at a reaction pressure of 1,000 to 1,800 kg/cm 2 using an initiator, sending the resulting reaction mixture from the top reaction zone to the bottom reaction zone, and further promoting the polymerization at 220° to 280° C using an initiator which is same as or different from the initiator in the top reaction zone, the improvement which comprises feeding 75% or more of the ethylene to the top reaction zone of the two-zone reactor, said two-zone reactor being constructed so that the volume ratio of top reaction zone to bottom reaction zone is 1.5 to 6 and being provided with two or more feed inlets for each of the ethylene and the initiator in the top reaction zone in the direction extending through the two reaction zones.

Inventors

  • 👤 Setsuo Nakai
  • 👤 Shinichiro Kita
  • 👤 Fumihiko Hiki
  • 👤 Masayuki Shimizu

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 17:15
CPC Classifications
C; C08; C08F; C08F110/00; C08F110/02; B; B01; B01J; B01J3/00; B01J3/04; B01J3/042

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 165 words
In a process for polymerizing ethylene in a two-zone autoclave reactor comprising a top reaction zone and a bottom reaction zone which process comprises polymerizing ethylene in said top reaction zone at 130° to 200° C and at a reaction pressure of 1,000 to 1,800 kg/cm 2 using an initiator, sending the resulting reaction mixture from the top reaction zone to the bottom reaction zone, and further promoting the polymerization at 220° to 280° C using an initiator which is same as or different from the initiator in the top reaction zone, the improvement which comprises feeding 75% or more of the ethylene to the top reaction zone of the two-zone reactor, said two-zone reactor being constructed so that the volume ratio of top reaction zone to bottom reaction zone is 1.5 to 6 and being provided with two or more feed inlets for each of the ethylene and the initiator in the top reaction zone in the direction extending through the two reaction zones.
Claim 2
Dependent Claim 165 words
In a process for polymerizing ethylene in a two-zone autoclave reactor comprising a top reaction zone and a bottom reaction zone which process comprises polymerizing ethylene in said top reaction zone at 130° to 200° C and at a reaction pressure of 1,000 to 1,800 kg/cm 2 using an initiator, sending the resulting reaction mixture from the top reaction zone to the bottom reaction zone, and further promoting the polymerization at 220° to 280° C using an initiator which is same as or different from the initiator in the top reaction zone, the improvement which comprises feeding 75% or more of the ethylene to the top reaction zone of the two-zone reactor, said two-zone reactor being constructed so that the volume ratio of top reaction zone to bottom reaction zone is 1.5 to 6 and being provided with two or more feed inlets for each of the ethylene and the initiator in the top reaction zone in the direction extending through the two reaction zones.
Claim 3
Dependent Claim 18 words
A process according to claim 1, wherein all of said ethylene is fed to the top reaction zone.
Claim 4
Dependent Claim 25 words
A process according to claim 1, wherein said volume ratio of top reaction zone to bottom reaction zone of the reactor is 2 to 5.
Claim 5
Dependent Claim 23 words
A process according to claim 1, wherein the number of the feed inlets for each of the ethylene and the initiator is two.
Claim 6
Dependent Claim 28 words
A process according to claim 1, wherein said two-zone autoclave reactor is a single reactor which is partitioned into the top and bottom reaction zones by a baffle.
Claim 7
Dependent Claim 23 words
A process according to claim 1, wherein said two-zone autoclave reactor is composed of two reactors connected in series by means of piping.

References Cited (Backward Citations)

CA676159A Cited
US3178404A Cited
US3756996A Cited
US3692763A Cited
US3875128A Cited
US3923767A Cited
US3963690A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-04-17 1981-10-17 1982-04-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-04-17 1985-10-17 1986-04-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-04-17 1989-10-17 1990-04-18 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag