Ethylene/α-olefin copolymers and lubricating oils

Patent metadata

Field	Value
Publication number	US-10329366-B2
Application number	US-201815993745-A
Country	US
Kind code	B2
Filing date	May 31, 2018
Priority date	Mar 28, 2014
Publication date	Jun 25, 2019
Grant date	Jun 25, 2019

Abstract

The invention has an object of providing ethylene/α-olefin copolymers having high randomness and a small number of double bonds in the copolymers. The ethylene/α-olefin copolymers of the invention are obtained by copolymerizing ethylene and an α-olefin having 3 to 20 carbon atoms in the presence of an olefin polymerization catalyst which includes a bridged metallocene compound (A) represented by the formula [I], and at least one compound (B) selected from organometallic compounds (B-1), organoaluminum oxy compounds (B-2) and compounds (B-3) capable of reacting with the bridged metallocene compound (A) to form an ion pair, and have a specific weight average molecular weight, a specific molecular weight distribution, a specific glass transition point and a specific value B.

First claim

The invention claimed is:

1. A method for producing ethylene/α-olefin copolymers comprising a step of copolymerizing ethylene and an α-olefin having 3 to 20 carbon atoms in the presence of an olefin polymerization catalyst including:
a bridged metallocene compound (A) represented by the general formula [I] below, and
at least one compound (B) selected from the group consisting of organometallic compounds (B-1), organoaluminum oxy compounds (B-2) and compounds (B-3) capable of reacting with the bridged metallocene compound (A) to form an ion pair,
the ethylene/α-olefin copolymers satisfying the following conditions (1) to (4):
(1) the weight average molecular weight is in the range of 1,000 to 50,000;
(2) the molecular weight distribution (Mw/Mn, Mw: weight average molecular weight, Mn: number average molecular weight) measured by gel permeation chromatography (GPC) is not more than 2.5;
(3) the glass transition point (Tg) measured with a differential scanning calorimeter (DSC) is below −50° C.; and
(4) the value B represented by the equation [1] below is not less than 1.1;

[

Math
.

⁢
2

]

B
=

P
OE

2
⁢

⁢

P
O

·

P
E

[
1
]

(in the equation [1], P E is the molar fraction of ethylene components, P O is the molar fraction of α-olefin components, and P OE is the molar fraction of ethylene⋅α-olefin sequences relative to all dyad sequences);

in the formula [I],
R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 and R 12 are each an atom or a substituent selected from the group consisting of a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, a silicon-containing group, a nitrogen-containing group, an oxygen-containing group, a halogen atom and a halogen-containing group, and may be the same as or different from one another,
R 13 and R 14 are each an atom or a substituent selected from the group consisting of a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, an aryl group, a substituted aryl group, a silicon-containing group, a nitrogen-containing group, an oxygen-containing group, a halogen atom and a halogen-containing group, and may be the same as or different from each other,
any adjacent substituents among R 1 to R 14 may be bonded together to form a ring,
Y is selected from Group XIV atoms,
M is a titanium atom, a zirconium atom or a hafnium atom,
Q is a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, an anionic ligand or a neutral ligand capable of coordination through a lone pair of electrons, and may be the same or different when plural,
n is an integer of 1 to 4, and
j is an integer of 1 to 4.

2. The method for producing ethylene/α-olefin copolymers according to claim 1 , wherein n in the general formula [I] is 1.

3. The method for producing ethylene/α-olefin copolymers according to claim 2 , wherein R 1 , R 2 , R 3 and R 4 in the general formula [I] are all hydrogen atoms.

4. The method for producing ethylene/α-olefin copolymers according to claim 3 , wherein one of R 13 and R 14 in the general formula [I] is an aryl group or a substituted aryl group.

5. The method for producing ethylene/α-olefin copolymers according to claim 4 , wherein one of R 13 and R 14 in the general formula [I] is an aryl group or a substituted aryl group and the other is an alkyl group having 1 to 20 carbon atoms.

6. The method for producing ethylene/α-olefin copolymers according to claim 1 , wherein M in the general formula [I] is a zirconium atom.

7. The method for producing ethylene/α-olefin copolymers according to claim 1 , wherein the compound (B-3) is used as the component (B).

8. The method for producing ethylene/α-olefin copolymers according to claim 1 , wherein the polymerization temperature in the copolymerization is not less than 130° C.

9. The method for producing ethylene/α-olefin copolymers according to claim 1 , wherein the α-olefin is propylene.

10. The method for producing ethylene/α-olefin copolymers according to claim 1 , wherein the content of ethylene-derived structural units in the copolymer is in the range of 30 to 70 mol %.

11. A lubricating oil composition comprising an ethylene/α-olefin copolymer obtained by the method for producing ethylene/α-olefin copolymers according to claim 1 .

12. An automobile lubricating oil comprising the lubricating oil composition described in claim 11 .

13. The automobile lubricating oil according to claim 12 , which is used as an automobile transmission oil and has a kinematic viscosity at 100° C. of not more than 7.5 mm 2 /s.

14. An industrial lubricating oil comprising the lubricating oil composition described in claim 11 .

Assignees

• Mitsui Chemicals Inc

Inventors

• Harada Katsuyoshi
• Endo Koji
• Mizukawa Tomoaki
• Matsuura Sadahiko

Classifications

• C10N2060/02

  Reduction, e.g. hydrogenation · CPC title

• C10N2040/25

  Internal-combustion engines · CPC title

• C10N2040/08

  Hydraulic fluids, e.g. brake-fluids · CPC title

• C10N2040/044

  for manual transmissions · CPC title

• C10N2040/042

  for automatic transmissions · CPC title