Conjugated diene-based polymer, branching agent, production method for conjugated diene-based polymer, extended conjugated diene-based polymer, rubber composition, and tire

Patent metadata

Field	Value
Publication number	US-11339240-B2
Application number	US-201917042230-A
Country	US
Kind code	B2
Filing date	Jul 31, 2019
Priority date	Oct 3, 2018
Publication date	May 24, 2022
Grant date	May 24, 2022

Abstract

A conjugated diene-based polymer of the present invention has an absolute molecular weight measured by viscosity detector-equipped GPC-light scattering measurement, of 40×10 4 or more and 5000×10 4 or less, has a branching number (Bn) measured by the viscosity detector-equipped GPC-light scattering measurement, of 8 or more, and has a modification ratio of 60% by mass or more.

First claim

The invention claimed is:

1. A conjugated diene-based polymer having an absolute molecular weight measured by viscosity detector-equipped GPC-light scattering measurement, of 100×10 4 or more and 5000×10 4 or less, and having a branching number (Bn) measured by the viscosity detector-equipped GPC-light scattering measurement, of 8 or more.

2. The conjugated diene-based polymer according to claim 1 , having a modification ratio of 60% by mass or more.

3. The conjugated diene-based polymer according to claim 1 , wherein the conjugated diene-based polymer is a conjugated diene-based polymer having a star polymer structure having 3 or more branches, wherein
at least one branched chain of the star structure comprises a portion derived from a vinyl-based monomer containing an alkoxysilyl group or a halosilyl group, and
the portion derived from the vinyl-based monomer containing an alkoxysilyl group or a halosilyl group further comprises a main chain branch structure.

4. The conjugated diene-based polymer according to claim 1 , wherein
the portion derived from the vinyl-based monomer containing an alkoxysilyl group or a halosilyl group is a monomer unit based on a compound represented by the following formula (1) or (2), and contains a branch point of a polymer chain containing the monomer unit based on the compound represented by the formula (1) or (2), and
at least one end of the conjugated diene-based polymer is coupled by using a coupling agent:

wherein in the formula (1), R 1 represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, or an aryl group having 6 to 20 carbon atoms, and optionally has a branched alkyl structure in a part of the alkyl group or the aryl group;
R 2 and R 3 each independently represent an alkyl group having 1 to 20 carbon atoms, or an aryl group having 6 to 20 carbon atoms, and optionally have a branched alkyl structure in a part of the alkyl group or the aryl group;
each of R 1 to R 3 , if present in a plural number, is respectively independent;
X 1 represents an independent halogen atom;
m represents an integer of 0 to 2, n represents an integer of 0 to 3, l represents an integer of 0 to 3, and (m+n+l) is 3;
in the formula (2), R 2 to R 5 each independently represent an alkyl group having 1 to 20 carbon atoms, or an aryl group having 6 to 20 carbon atoms, and optionally have a branched alkyl structure in a part of the alkyl group or the aryl group, and each of R 2 to R 5 , if present in a plural number, is respectively independent;
X 2 and X 3 represent an independent halogen atom;
m represents an integer of 0 to 2, n represents an integer of 0 to 3, l represents an integer of 0 to 3, and (m+n+l) is 3; and
a represents an integer of 0 to 2, b represents an integer of 0 to 3, c represents an integer of 0 to 3, and (a+b+c) is 3.

5. The conjugated diene-based polymer according to claim 4 , containing a monomer unit based on a compound represented by the formula (1) wherein R 1 is a hydrogen atom, and m is 0.

6. The conjugated diene-based polymer according to claim 4 , containing a monomer unit based on a compound represented by the formula (2) wherein m is 0 and b is 0.

7. The conjugated diene-based polymer according to claim 4 , containing a monomer unit based on a compound represented by the formula (1) wherein R 1 is a hydrogen atom, m is 0, and l is 0.

8. The conjugated diene-based polymer according to claim 4 , containing a monomer unit based on a compound represented by the formula (2) wherein m is 0, l is 0, a is 0, and b is 0.

9. The conjugated diene-based polymer according to claim 4 , containing a monomer unit based on a compound represented by the formula (1) wherein R 1 is a hydrogen atom, l is 0, and n is 3.

10. A branching agent for the conjugated diene-based polymer according to claim 4 , wherein the branching agent is a compound represented by the following formula (1) or (2):

wherein in the formula (1), R 1 represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, or an aryl group having 6 to 20 carbon atoms, and optionally has a branched alkyl structure in a part the alkyl group or the aryl group;
R 2 and R 3 each independently represent an alkyl group having 1 to 20 carbon atoms, or an aryl group having 6 to 20 carbon atoms, and optionally have a branched alkyl structure in a part the alkyl group or the aryl group;
each of R 1 to R 3 , if present in a plural number, is respectively independent;
X1 represents an independent halogen atom;
m represents an integer of 0 to 2, n represents an integer of 0 to 3, l represents an integer of 0 to 3, and (m+n+l) is 3;
in the formula (2), R 2 to R 5 each independently represent an alkyl group having 1 to 20 carbon atoms, or an aryl group having 6 to 20 carbon atoms, and optionally have a branched alkyl structure in a part the alkyl group or aryl group, and each of R 2 to R 5 , if present in a plural number, is respectively independent;
X 2 and X 3 represent an independent halogen atom;
m represents an integer of 0 to 2, n represents an integer of 0 to 3, l represents an integer of 0 to 3, and (m+n+l) is 3; and
a represents an integer of 0 to 2, b represents an integer of 0 to 3, c represents an integer of 0 to 3, and (a+b+c) is 3.

11. The branching agent according to claim 10 , wherein the branching agent is a compound represented by the formula (1) wherein R 1 is a hydrogen atom and m is 0.

12. The branching agent according to claim 10 , wherein the branching agent is a compound represented by the formula (2) wherein m is 0, and b is 0.

13. The branching agent according to claim 10 , wherein the branching agent is a compound represented by the formula (1) wherein R 1 is a hydrogen atom, m is 0, and l is 0.

14. The branching agent according to claim 10 , wherein the branching agent is a compound represented by the formula (2) wherein m is 0, l is 0, a is 0, and b is 0.

15. The branching agent according to claim 10 , wherein the branching agent is a compound represented by the formula (1) wherein R 1 is a hydrogen atom, l is 0, and n is 3.

16. An extended conjugated diene-based polymer comprising:
100 parts by mass of the conjugated diene-based polymer according to claim 1 ; and
1 to 60 parts by mass of at least one selected from the group consisting of an extender oil, a liquid rubber, and a resin.

17. A rubber composition comprising:
a rubber component; and
5.0 parts by mass or more and 150 parts by mass or less of a filler based on 100 parts by mass of the rubber component,
wherein the rubber component contains, based on a total amount of the rubber component, 10% by mass or more of the conjugated diene-based polymer according to claim 1 .

18. A tire comprising the rubber composition according to claim 17 .

Assignees

• Asahi Chemical Ind

Inventors

• Hisamura Kenta
• Yamamoto Miho

Classifications

• C08F8/42

  Introducing metal atoms or metal-containing groups · CPC title

• C08L15/00

  Compositions of rubber derivatives (C08L11/00, C08L13/00 take precedence) · CPC title

• B60C1/00

  Tyres characterised by the chemical composition or the physical arrangement or mixture of the composition · CPC title

• C08K3/04

  Carbon · CPC title

• C08F236/10 Primary

  with vinyl-aromatic monomers · CPC title