Modified conjugated diene-based polymer, method for preparing the same and rubber composition including the same

Patent metadata

Field	Value
Publication number	US-12110353-B2
Application number	US-202017420235-A
Country	US
Kind code	B2
Filing date	Sep 11, 2020
Priority date	Sep 11, 2019
Publication date	Oct 8, 2024
Grant date	Oct 8, 2024

Abstract

A modified conjugated diene-based polymer and a rubber composition including the same are disclosed herein. The modified conjugated diene-based polymer has excellent processability and good tensile strength and viscoelasticity. In some embodiments, a modified conjugated diene-based polymer includes silicon (Si) and nitrogen (N), and has an N content of 150 ppm or more based on the weight of the modified conjugated diene-based polymer and a rate of change of mooney viscosity (MV R ) of 20% or less.

First claim

The invention claimed is:

1. A modified conjugated diene-based polymer comprising silicon (Si) and nitrogen (N), and satisfying the following conditions a) and b):
a) a N content of 150 ppm or more, based on the weight of the modified conjugated diene-based polymer; and
b) a rate of change of mooney viscosity (MV R ) of 20% or less, wherein MV R is calculated according to the following Mathematical Formula 1:
MV R =[( MV f −MV i )/ MV i ]×100  [Mathematical Formula 1]

in Mathematical Formula 1, MV f is mooney viscosity at 100° C. after standing the polymer at 25° C. for 30 days, and MV i is initial mooney viscosity of the polymer at 100° C.

2. The modified conjugated diene-based polymer of claim 1 , wherein the modified conjugated diene-based polymer has a molar ratio (N/Si) of nitrogen to silicon of 0.75 or more.

3. The modified conjugated diene-based polymer of claim 1 , wherein the modified conjugated diene-based polymer has the N content of 170 ppm or more, based on the weight of the modified conjugated diene-based polymer.

4. The modified conjugated diene-based polymer of claim 1 , wherein the modified conjugated diene-based polymer has MV R of 15% or less.

5. The modified conjugated diene-based polymer of claim 1 , wherein an Si content is 50 ppm or more, based on the weight of the modified conjugated diene-based polymer.

6. The modified conjugated diene-based polymer of claim 1 , comprising:
a first chain comprising a repeating unit derived from a conjugated diene-based monomer;
a second chain comprising a repeating unit derived from an N-functional group-containing monomer; and
a derived unit from an alkoxysilane-based compound.

7. The modified conjugated diene-based polymer of claim 6 , wherein the alkoxysilane-based compound is an amine-containing alkoxysilane-based compound or a non-amine-containing alkoxysilane-based compound.

8. The modified conjugated diene-based polymer of claim 6 , wherein the first chain further comprises a repeating unit derived from an aromatic vinyl-based monomer.

9. The modified conjugated diene-based polymer of claim 6 , wherein the second chain further comprises a derived unit from a conjugated diene-based monomer.

10. The modified conjugated diene-based polymer of claim 1 , wherein a number average molecular weight (Mn) is 1,000 g/mol to 2,000,000 g/mol, a weight average molecular weight (Mw) is 1,000 g/mol to 3,000,000 g/mol, and a peak average molecular weight (Mp) is 1,000 g/mol to 3,000,000 g/mol.

11. A method for preparing the modified conjugated diene-based polymer of claim 1 , the method comprising:
polymerizing a conjugated diene-based monomer, or a conjugated diene-based monomer and an aromatic vinyl-based monomer, in the presence of a polymerization initiator in a carbon solvent to prepare an active first chain;
reacting the active first chain with an alkoxysilane-based modifier to prepare a modified active first chain; and
reacting the modified active first chain and a macromonomer comprising a repeating unit derived from an N-functional group-containing monomer to prepare the modified conjugated diene-based polymer.

12. The method for preparing the modified conjugated diene-based polymer of claim 11 , wherein the macromonomer further comprises a derived unit from a conjugated diene-based monomer.

13. The method for preparing the modified conjugated diene-based polymer of claim 11 , wherein the macromonomer is prepared by a polymerization reaction of an N-functional group-containing monomer, or an N-functional group-containing monomer and a conjugated diene-based monomer in the presence of an organolithium compound in a hydrocarbon solvent.

14. The method for preparing the modified conjugated diene-based polymer of claim 11 , wherein the alkoxysilane-based compound is used in an amount of 0.1 mol to 10 mol based on 1 mol of the polymerization initiator.

15. The method for preparing the modified conjugated diene-based polymer of claim 11 , wherein the macromonomer is used in an amount of 0.1 to 4.0 mol based on 1 mol of the polymerization initiator.

16. A rubber composition comprising the modified conjugated diene-based polymer of claim 1 , and a filler.

17. The rubber composition of claim 16 , wherein the rubber composition comprises 0.1 parts by weight to 200 parts by weight of the filler based on 100 parts by weight of the modified conjugated diene-based polymer.

Assignees

• Lg Chemical Ltd

Inventors

• Oh Jung Hwan
• Yoo Suk Joon
• Lee He Seung
• Choi Jae Sun

Classifications

• C08L9/06

  Copolymers with styrene · CPC title

• C08F226/06

  by a heterocyclic ring containing nitrogen · CPC title

• C08F2/06

  Organic solvent · CPC title

• C08C19/25

  Incorporating silicon atoms into the molecule · CPC title

• C08C19/22

  Incorporating nitrogen atoms into the molecule · CPC title