Method of preparing conjugated diene-based polymer by continuous polymerization

Patent metadata

Field	Value
Publication number	US-11312798-B2
Application number	US-201716763149-A
Country	US
Kind code	B2
Filing date	Dec 22, 2017
Priority date	Nov 13, 2017
Publication date	Apr 26, 2022
Grant date	Apr 26, 2022

Abstract

The present invention relates to a method of preparing a conjugated diene-based polymer by continuous polymerization using two or more reactors, and relates to a method of preparing a conjugated diene-based polymer which is capable of providing a conjugated diene-based polymer having improved Mooney viscosity and excellent cis 1,4 bond content and linearity, by controlling the injection amount of a conjugated diene-based monomer to each reactor in a specific ratio and resolving the deterioration phenomenon of physical properties, which might be generated in continuous reaction.

First claim

The invention claimed is:

1. A method of preparing a conjugated diene-based polymer comprising:
firstly injecting a diene-based monomer to a first reactor to perform a polymerization reaction in a presence of a catalyst composition in a hydrocarbon solvent, and transporting a polymerization reaction product to a second reactor; and
secondly injecting the diene-based monomer to the second reactor to perform a polymerization reaction in a presence of a hydrocarbon solvent and a catalyst composition,
wherein injection amounts of the diene-based monomer satisfy the following Mathematical Formula 1:
2.7≤ x/y≤ 6.0  [Mathematical Formula 1]

in Mathematical Formula 1, x is a first injection amount (weight) of the diene-based monomer, and y is a second injection amount (weight) of the diene-based monomer,
wherein the method is a continuous preparation method, wherein cis 1,4 bond content (Cis, wt %) and Mooney viscosity (MV, MU) of a diene-based polymer polymerized in the first reactor and a diene-based polymer polymerized in the second reactor satisfy the following Mathematical Formula 2:
−0.02≤(Δ Cis )/(Δ MV ))  [Mathematical Formula 2]

in Mathematical Formula 2,
ΔC is a value obtained by subtracting a cis 1,4 bond content of the diene-based polymer polymerized in the first reactor from a cis 1,4 bond content of the diene-based polymer polymerized in the second reactor, and
ΔMV is a value obtained by subtracting a Mooney viscosity of the diene-based polymer polymerized in the first reactor from a Mooney viscosity of the diene-based polymer polymerized in the second reactor.

2. The method of claim 1 , wherein the diene-based monomer comprises 1,3-butadiene, isoprene, 1,3-pentadiene, 1,3-hexadiene, 2,3-dimethyl-1,3-butadiene, 2-ethyl-1,3-butadiene, 2-methyl-1,3-pentadiene, 3-methyl-1,3-pentadiene, 4-methyl-1,3-pentadiene, 2,4-hexadiene, piperylene, 3-butyl-1,3-octadiene, 2-phenyl-1,3-octadiene or a mixture of two or more thereof.

3. The method of claim 1 , wherein the polymerization reaction in the first reactor and the polymerization reaction in the second reactor is performed at a temperature of −20° C. to 200° C.

4. The method of claim 1 , wherein the catalyst composition comprises a lanthanide rare earth element-containing compound, and at least one of an alkylating agent, a halide or a conjugated diene-based monomer.

5. The method of claim 4 , wherein the lanthanide rare earth element-containing compound comprises a neodymium compound represented by the following Formula 1:

in Formula 1,
R a to R c are each independently hydrogen or alkyl of 1 to 12 carbon atoms, where R a and R c are not hydrogen at the same time.

6. The method of claim 5 , wherein the neodymium compound is one or more selected from the group consisting of Nd(2,2-diethyl decanoate) 3 , Nd(2,2-dipropyl decanoate) 3 , Nd(2,2-dibutyl decanoate) 3 , Nd(2,2-dihexyl decanoate) 3 , Nd(2,2-dioctyl decanoate) 3 , Nd(2-ethyl-2-propyl decanoate) 3 , Nd(2-ethyl-2-butyl decanoate) 3 , Nd(2-ethyl-2-hexyl decanoate) 3 , Nd(2-propyl-2-butyl decanoate) 3 , Nd(2-propyl-2-hexyl decanoate) 3 , Nd(2-propyl-2-isopropyl decanoate) 3 , Nd(2-butyl-2-hexyl decanoate) 3 , Nd(2-hexyl-2-octyl decanoate) 3 , Nd(2,2-diethyl octanoate) 3 , Nd(2,2-dipropyl octanoate) 3 , Nd(2,2-dibutyl octanoate) 3 , Nd(2,2-dihexyl octanoate) 3 , Nd(2-ethyl-2-propyl octanoate) 3 , Nd(2-ethyl-2-hexyl octanoate) 3 , Nd(2,2-diethyl nonanoate) 3 , Nd(2,2-dipropyl nonanoate) 3 , Nd(2,2-dibutyl nonanoate) 3 , Nd(2,2-dihexyl nonanoate) 3 , Nd(2-ethyl-2-propyl nonanoate) 3 , and Nd(2-ethyl-2-hexyl nonanoate) 3 .

Assignees

• Lg Chemical Ltd

Inventors

• Choi Soo Young
• Yoo Suk Joon
• Ahn Jeong Heon
• Park Sung Ho
• Kang Suk Youn

Classifications

• Y02T10/86

  Optimisation of rolling resistance, e.g. weight reduction · CPC title

• C08F2500/03

  Narrow molecular weight distribution, i.e. Mw/Mn < 3 · CPC title

• C08F4/545

  rare earths being present, e.g. triethylaluminium + neodymium octanoate · CPC title

• C08F136/06 Primary

  Butadiene · CPC title

• C08F4/44

  selected from light metals, zinc, cadmium, mercury, copper, silver, gold, boron, gallium, indium, thallium, rare earths or actinides · CPC title