Silica-coated alumina activator-supports for metallocene catalyst compositions
US-9346896-B2 · May 24, 2016 · US
Method of producing polyethylene and polyethylene thereof
US11034783B2 · US · B2
| Field | Value |
|---|---|
| Publication number | US-11034783-B2 |
| Application number | US-201916278212-A |
| Country | US |
| Kind code | B2 |
| Filing date | Feb 18, 2019 |
| Priority date | Feb 11, 2014 |
| Publication date | Jun 15, 2021 |
| Grant date | Jun 15, 2021 |
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- Title
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Abstract
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A system and method of producing polyethylene, including: polymerizing ethylene in presence of a catalyst system in a reactor to form polyethylene, wherein the catalyst system includes a first catalyst and a second catalyst; and adjusting reactor conditions and an amount of the second catalyst fed to the reactor to control melt index (MI), density, and melt flow ratio (MFR) of the polyethylene.
First claim
Opening claim text (preview).
What is claimed is: 1. A polymer comprising: polyethylene formed: in a polymerization reactor via a polymerization catalyst system comprising a first catalyst and a second catalyst; and by adjusting operating conditions of the polymerization reactor including at least one of hydrogen concentration, and comonomer concentration and an amount of the second catalyst fed to the polymerization reactor to control melt index (MI) and density of the polyethylene based on a target melt flow ratio (I 21 /I 2 ) in a range of from 20 to 60, the polyethylene having: a value for Mw1/Mw2 of at least about 2.0 or more, wherein Mw1/Mw2 is a ratio of a weight average molecular weight (Mw1) for a first half of a temperature rising elution (TREF) curve to a weight average molecular weight (Mw2) for a second half of the TREF curve; and a value for Tw1-Tw2 of less than about −15° C., wherein Tw1-Tw2 is a difference of a weight average elution temperature (Tw1) for the first half of the TREF curve to a weight average elution temperature (Tw2) for the second half of the TREF curve. 2. The polymer of claim 1 , wherein the polyethylene comprises a copolymer of ethylene and an alpha olefin comonomer having from 4 to 20 carbon atoms. 3. The polymer of claim 2 , wherein the alpha olefin comonomer comprises 1-hexene. 4. The polymer of claim 1 , wherein the polyethylene comprises a bimodal polyethylene with respect to molecular weight (Mw). 5. The polymer of claim 1 , wherein the MI of the polyethylene is in a range from 0.1 to 5.0 dg/min. 6. The polymer of claim 1 , wherein the first catalyst comprises bis(n-propylcyclopentadienyl) Hafnium dimethyl. 7. The polymer of claim 6 , wherein the second catalyst comprises di(1-ethylindenyl) zirconium dimethyl.
Assignees
Inventors
Classifications
- C08F4/65925Primary
two cyclopentadienyl rings being mutually non-bridged · CPC title
- C08F210/16Primary
Copolymers of ethene with alpha-alkenes, e.g. EP rubbers · CPC title
two cyclopentadienyl rings being mutually bridged · CPC title
with non-conjugated dienes, e.g. EPT rubbers · CPC title
in combination with an organoaluminium compound · CPC title
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- What does patent US11034783B2 cover?
- A system and method of producing polyethylene, including: polymerizing ethylene in presence of a catalyst system in a reactor to form polyethylene, wherein the catalyst system includes a first catalyst and a second catalyst; and adjusting reactor conditions and an amount of the second catalyst fed to the reactor to control melt index (MI), density, and melt flow ratio (MFR) of the polyethylene.
- Who is the assignee on this patent?
- Univation Tech Llc
- What technology area does this patent fall under?
- Primary CPC classification C08F4/65925. Mapped technology areas include Chemistry & Metallurgy.
- When was this patent published?
- Publication date Tue Jun 15 2021 00:00:00 GMT+0000 (Coordinated Universal Time) (B2). Legal status and post-grant events are not shown on this page.
- What related patents are in patentsdb?
- We list 4 related publications on this page (citations in our corpus or others sharing the same primary CPC).