Polyolefin

Patent metadata

Field	Value
Publication number	US-9701768-B2
Application number	US-201415021149-A
Country	US
Kind code	B2
Filing date	Sep 29, 2014
Priority date	Sep 30, 2013
Publication date	Jul 11, 2017
Grant date	Jul 11, 2017

Abstract

The present invention relates to a polyolefin having a molecular weight distribution of 1.5 to 3.0 and having a branch gradient number (BGN) of 0.01 to 1.0. According to the present invention, there is provided the polyolefin having a narrow molecular weight distribution and showing a unique comonomer distribution to have excellent impact strength and mechanical physical properties.

First claim

The invention claimed is:

1. A polyolefin, obtained by a process comprising:
copolymerizing ethylene with at least one alpha-olefin comonomer,
wherein the polyolefin has a molecular weight distribution of 1.5 to 3.0 and has a branch gradient number (BGN) of 0.01 to 1.0,
wherein the BGN is calculated by Equation 1 below:

Branch
⁢

⁢
Gradient
⁢

⁢
Number
⁢

⁢

(
BGN
)

=

(

Branch
⁢

⁢
content
⁢

⁢
of
⁢

⁢
high
⁢

⁢
molecular
⁢

⁢
weight

-

Branch
⁢

⁢
content
⁢

⁢
of
⁢

⁢
low
⁢

⁢
molecular
⁢

⁢
weight

)

(

Branch
⁢

⁢

⁢
content
⁢

⁢
of
⁢

⁢
low
⁢

⁢
molecular
⁢

⁢
weight

)

[

Equation
⁢

⁢
1

]

wherein in Equation 1,
the branch gradient number is a measure of a distribution of a content of the at least one alpha-olefin comonomer according to a molecular weight of polyolefin,
the branch content is a number of the at least one alpha-olefin comonomer incorporated per 1000 carbon atoms in a molecular weight distribution curve using GPC-FTIR in which an x-axis represents a log value of a molecular weight (log Mw) and a y-axis value represents a molecular weight distribution (dwt/dlog Mw) with respect to the log value,
the branch content of low molecular weight is a branch content at a left side boundary of the curve without a first 10% content of the curve,
the branch content of high molecular weight is a branch content at a right side boundary of the curve without the last 10% content of the curve.

2. The polyolefin of claim 1 , wherein the polyolefin has a density of 0.85 to 0.91 g/cc.

3. The polyolefin of claim 1 , wherein the number of branch content is 20 to 120.

4. The polyolefin of claim 1 , wherein the at least one alpha-olefin comonomer has a content of 5 to 70 wt % on the basis of overall polyolefin.

5. The polyolefin of claim 1 , wherein the polyolefin is obtained by copolymerizing ethylene with the at least one alpha-olefin comonomer in the presence of a hybrid metallocene catalyst, which comprises a first metallocene compound represented by Chemical Formula 1 and a second metallocene compound represented by Chemical Formula 2:

wherein in Chemical Formula 1,
R1 and R2 are each independently hydrogen; C1 to C20 alkyl; C2 to C20 alkenyl; C6 to C20 aryl; C1 to C20 alkylsilyl; C6 to C20 arylsilyl; C7 to C20 alkylaryl; C7 to C20 arylalkyl; or a metalloid of a Group 4 metal substituted with hydrocarbyl; and R1 and R2 or two R2 groups are optionally linked with each other via alkylidine including C1 to 20 alkyl or C6 to C20 aryl functional group to

Assignees

• Lg Chemical Ltd

Inventors

• Kum Don Ho
• Lee Choong Hoon
• Park Sang Eun
• Jung Seung Hwan
• Cho Yoon Hee
• Do Young Shil
• Park Hae Woong
• Lee Young Woo

Classifications

• C08F4/022

  Magnesium halide as support anhydrous or hydrated or complexed by means of a Lewis base for Ziegler-type catalysts · CPC title

• C08F210/16 Primary

  Copolymers of ethene with alpha-alkenes, e.g. EP rubbers · CPC title

• C08F10/00 Primary

  Homopolymers and copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond · CPC title

• C08F4/65912

  in combination with an organoaluminium compound · CPC title

• C08L23/0815

  with aliphatic 1-olefins containing one carbon-to-carbon double bond · CPC title