Method of preparing conjugated diene-based polymer and apparatus for preparing conjugated diene-based polymer

Patent metadata

Field	Value
Publication number	US-11370858-B2
Application number	US-201916631640-A
Country	US
Kind code	B2
Filing date	Jan 10, 2019
Priority date	Feb 5, 2018
Publication date	Jun 28, 2022
Grant date	Jun 28, 2022

Abstract

A method of preparing a conjugated diene-based polymer is provided. The method includes: adding a conjugated diene-based monomer, a catalyst, and a solvent to parallel polymerization reactors, performing a polymerization reaction to prepare a first polymer solution including a first conjugated diene-based polymer; and adding the first polymer solution to a polymerization reactor connected in series to the parallel polymerization reactors, performing the polymerization reaction to prepare a second polymer solution including a second conjugated diene-based polymer. After the polymerization reaction in the series polymerization reactor, gas produced by polymerization heat is condensed in the series polymerization reactor and refluxed to the parallel polymerization reactors, and a reaction temperature of the series polymerization reactor is maintained to be lower than a reaction temperature of the parallel polymerization reactors by 10° C. or more.

First claim

The invention claimed is:

1. A method of preparing a conjugated diene-based polymer, comprising:
adding a conjugated diene-based monomer, a catalyst, and a solvent to parallel polymerization reactors, wherein the parallel polymerization reactors include two or more polymerization reactors connected in parallel, and
performing a polymerization reaction to prepare a first polymer solution including a first conjugated diene-based polymer; and
adding the first polymer solution discharged from the parallel polymerization reactors to a series polymerization reactor connected in series to the parallel polymerization reactors and
performing a polymerization reaction to prepare a second polymer solution including a second conjugated diene-based polymer,
wherein after the polymerization reaction in the series polymerization reactor, gas produced by polymerization heat is condensed by a condenser in the series polymerization reactor and refluxed to the parallel polymerization reactors, and
a reaction temperature of the series polymerization reactor is maintained to be lower than a reaction temperature of the parallel polymerization reactors by 10° C. or more.

2. The method of claim 1 , further comprising:
adding the first polymer solution discharged from the parallel polymerization reactors to an at least one polymerization reactor located between the parallel polymerization reactors and the series polymerization reactor, wherein the at least one polymerization reactor is connected in series between the parallel polymerization reactors and the series polymerization reactor, and performing a polymerization reaction.

3. The method of claim 2 , wherein the reaction temperature of the series polymerization reactor is maintained to be lower than a reaction temperature of the at least one polymerization reactor directly connected to the series polymerization reactor, among one or more polymerization reactors connected in series between the parallel polymerization reactors and the series polymerization reactor, by 10° C. or more.

4. The method of claim 1 , wherein the reaction temperature of the series polymerization reactor is maintained to be lower than the reaction temperature of the parallel polymerization reactors by 10° C. to 25° C.

5. The method of claim 1 , wherein a pressure of the series polymerization reactor is maintained to be lower than a pressure of the parallel polymerization reactors by 0.5 barg or more.

6. The method of claim 1 , wherein a pressure of the series polymerization reactor is maintained to be lower than the pressure of the parallel polymerization reactors by 1.0 barg to 2.5 barg.

7. The method of claim 1 , wherein the catalyst is one or more Ziegler-Natta catalysts selected from the group consisting of transition metal compounds, lanthanum-based compounds, organic aluminum compounds, and fluorinated compounds; or an organolithium catalyst.

8. The method of claim 1 , wherein the solvent is a hydrocarbon-based solvent.

9. The method of claim 1 , wherein the method is a continuous preparation method of a conjugated diene-based polymer.

10. An apparatus for preparing a conjugated diene-based polymer, comprising:
parallel polymerization reactors, wherein the parallel polymerization reactors include two or more polymerization reactors connected in parallel;
at least two separate supply pipes coupled to each of the parallel polymerization reactors and configured to supply different materials thereto; and
a series polymerization reactor connected in series to the parallel polymerization reactors; and
one or more polymerization reactors located between the parallel polymerization reactors and the series polymerization reactor, wherein the one or more polymerization reactor is connected in series between the parallel polymerization reactors and the series polymerization reactor,
wherein the series polymerization reactor comprises a condenser for condensing gas produced by polymerization heat and refluxing the gas to the parallel polymerization reactors, and
a reaction temperature of the series polymerization reactor is maintained to be lower than a reaction temperature of the parallel polymerization reactors by 10° C. or more.

11. The apparatus of claim 10 , wherein the parallel polymerization reactors and the series polymerization reactor are continuous stirred tank reactors (CSTR).

12. The apparatus of claim 10 , wherein two or more polymerization reactors of the parallel polymerization reactors comprise a condenser for condensing gas produced by polymerization heat and refluxing the gas to each of the parallel polymerization reactors, respectively.

13. The apparatus of claim 10 , wherein the reaction temperature of the series polymerization reactor is maintained to be lower than a reaction temperature of a polymerization reactor directly connected to the series polymerization reactor, among the one or more polymerization reactors connected in series between the parallel polymerization reactors and the series polymerization reactor, by 10° C. or more.

14. The apparatus of claim 10 , wherein the reaction temperature of the series polymerization reactor is maintained to be lower than the reaction temperature of the parallel polymerization reactors, by 10 to 25° C.

15. The apparatus of claim 13 wherein, the reaction temperature of the polymerization reactor is maintained to be lower than the reaction temperature of the series polymerization reactor directly connected to the polymerization reactor, among the one or more polymerization reactors connected in series between the parallel polymerization reactors and the polymerization reactor, by 10 to 25° C.

Assignees

• Lg Chemical Ltd

Inventors

• Ko Jun Seok
• Jeong Hoi In
• Hwang Woo Sung
• Kim Dong Min
• Lee Jeong Seok

Classifications

• B01J19/2445

  placed in parallel · CPC title

• C08F4/48

  selected from lithium, rubidium, caesium or francium {(C08F4/461 takes precedence)} · CPC title

• B01J19/245

  placed in series · CPC title

• C08F36/06 Primary

  Butadiene · CPC title

• C08F4/52

  selected from boron, aluminium, gallium, indium, thallium or rare earths (C08F4/14 takes precedence) · CPC title