Preparation method of a polypropylene and a polypropylene obtained therefrom

Patent metadata

Field	Value
Publication number	US-9771441-B2
Application number	US-201415023626-A
Country	US
Kind code	B2
Filing date	Sep 30, 2014
Priority date	Sep 30, 2013
Publication date	Sep 26, 2017
Grant date	Sep 26, 2017

Abstract

The present invention relates to a preparation method of a polypropylene and a polypropylene obtained therefrom. More specifically, it relates to a method of preparing a polypropylene by using a catalyst that includes a novel metallocene compound having an excellent polymerization activity, and a polypropylene obtained by the method.
According to the present invention, since the polypropylene is prepared by polymerizing propylene by using a novel metallocene compound having an excellent polymerization activity and hydrogen reactivity, the properties of the polypropylene can be easily controlled and the polypropylene having excellent mechanical properties can be obtained.

First claim

What is claimed is:

1. A method of preparing a polypropylene, including a step of polymerizing propylene in the presence of a catalyst including a metallocene compound represented by Chemical Formula 1,
wherein the catalyst is a supported catalyst including the metallocene compound, an alkylaluminoxane cocatalyst, and a boron-based cocatalyst which are supported on a carrier:

in Chemical Formula 1,
M 1 is a group 3 transition metal, a group 4 transition metal, a group 5 transition metal, a lanthanide transition metal, or an actinide transition metal;
X is, same to or different from each other, a halogen;
A is a group 14 element bridging indenyl groups;
R 1 is a C 1 -C 20 alkyl, alkenyl, alkylaryl, arylalkyl, or aryl;
R 2 is hydrogen, a C 1 -C 20 alkyl, alkenyl, alkylaryl, arylalkyl, or aryl;
R 3 , R 3′ , R 4 , and R 4′ are, same to or different from each other, respectively a C 1 -C 20 alkyl, alkenyl, alkylaryl, arylalkyl, or aryl; and
n is an integer of 1 to 20.

2. The method of preparing a polypropylene according to claim 1 , wherein R 1 and R 2 are respectively a C 1 -C 4 alkyl; R 3 and R 3′ are respectively a C 1 -C 20 alkyl, alkenyl, or arylalkyl; R 4 and R 4′ are respectively a C 6 -C 20 aryl or alkylaryl; n is an integer of 1 to 6; and A is silicon (Si) in Chemical Formula 1.

3. The method of preparing a polypropylene according to claim 1 , wherein the alkylaluminoxane cocatalyst is one or more selected from the group consisting of methylaluminoxane, ethylaluminoxane, propylaluminoxane, and butylaluminoxane.

4. The method of preparing a polypropylene according to claim 1 , wherein the boron-based cocatalyst is one or more selected from the group consisting of dimethylanilinium tetrakis(pentafluorophenyl)borate, trityl tetrakis(pentafluorophenyl)borate, and methylanilinium tetrakis(pentafluorodiphenyl)borate.

5. The method of preparing a polypropylene according to claim 1 , wherein the carrier is one or more selected from the group consisting of silica, silica-alumina and silica-magnesia.

6. The method of preparing a polypropylene according to claim 1 , wherein the polymerization of propylene is carried out at the temperature of 25 to 500° C. and the pressure of 1 to 100 kgf/cm 2 for 1 to 24 hrs.

7. The method of preparing a polypropylene according to claim 1 , wherein the polymerization is carried out in the presence of hydrogen gas (H 2 ) of 30 to 2,000 ppm, based on the weight of propylene.

Assignees

• Lg Chemical Ltd

Inventors

• Choi Ji Ho
• Park Churl Young
• Noh Kyung Seop
• Kim Won Hee
• Jeon Sang Jin
• Choi Ra Yun
• Kim Byung Seok

Classifications

• C08F4/65908

  in combination with an ionising compound other than alumoxane, e.g. (C6F5)4B-X+ · CPC title

• C08F4/65912

  in combination with an organoaluminium compound · CPC title

• C08F4/65927

  two cyclopentadienyl rings being mutually bridged · CPC title

• C08F4/65916

  supported on a carrier, e.g. silica, MgCl2, polymer · CPC title

• C08F110/06 Primary

  Propene · CPC title