Method for producing modified polymer, and rubber composition

Patent metadata

Field	Value
Publication number	US-9969850-B2
Application number	US-201414771900-A
Country	US
Kind code	B2
Filing date	Mar 7, 2014
Priority date	Mar 7, 2013
Publication date	May 15, 2018
Grant date	May 15, 2018

Abstract

Acido-basic properties of a system containing a polymer obtained by decomposing by oxidative cleavage of a carbon-carbon double bond, and a trifunctional molecule having an alkoxysilyl group in the structure as represented by the formula (A) are changed such that the system is changed into a basic system when the system is acidic and the system is changed into an acidic system when the system is basic to combine the decomposed polymer and the trifunctional molecule, thereby introducing the alkoxysilyl group into the main chain. Furthermore, acido-basic properties of a system containing a polymer obtained by decomposing by oxidative cleavage of a carbon-carbon double bond to decrease the molecular weight, and a functional molecule having an alkoxysilyl group as represented by the formula (a) are changed in the same manner as above to combine the decomposed polymer and the functional molecule, thereby introducing the alkoxysilyl group in a molecular terminal.

First claim

The invention claimed is:

1. A method for producing a modified polymer, comprising changing acido-basic properties of a system containing a polymer obtained by decomposing a polymer having a carbon-carbon double bond in a main chain by oxidative cleavage of the carbon-carbon double bond to decrease the molecular weight, and a functional molecule having an alkoxysilyl group in the structure such that the system is changed into a basic system when the system is acidic and the system is changed into an acidic system when the system is basic to combine the decomposed polymer and the functional molecule, thereby obtaining a modified polymer having an alkoxysilyl group introduced in a main chain or at least one molecular terminal.

2. The method for producing a modified polymer according to claim 1 , comprising changing acido-basic properties of a system containing a polymer obtained by decomposing a polymer having a carbon-carbon double bond in a main chain by oxidative cleavage of the carbon-carbon double bond to decrease the molecular weight, and a trifunctional molecule having an alkoxysilyl group in the structure as represented by the following formula (A) such that the system is changed into a basic system when the system is acidic and the system is changed into an acidic system when the system is basic to combine the decomposed polymer and the trifunctional molecule, thereby obtaining a modified polymer having an alkoxysilyl group introduced in a main chain;

wherein R 1 , R 2 and R 3 each represent an aldehyde group or a carbonyl group, and R 4 represents an alkyl group having from 1 to 10 carbon atoms.

3. The method for producing a modified polymer according to claim 2 , wherein the decomposed polymer has a structure as represented by the following formula (1) in the terminal;

wherein R 5 represents a hydrogen atom or a methyl group.

4. The method for producing a modified polymer according to claim 2 , wherein the trifunctional molecule having the alkoxysilyl group in the structure as represented by the formula (A) is obtained by oxidative cleavage of a carbon-carbon double bond in the trifunctional molecule having at least one vinyl group.

5. The method for producing a modified polymer according to claim 2 , which obtains a modified polymer having at least one of bonding structures as represented by the following formulae (2) to (5):

wherein R 4 represents an alkyl group having from 1 to 10 carbon atoms.

6. The method for producing a modified polymer according to claim 1 , comprising changing acido-basic properties of a system containing a polymer obtained by decomposing a polymer having a carbon-carbon double bond in a main chain by oxidative cleavage of the carbon-carbon double bond to decrease the molecular weight, and a functional molecule having an alkoxysilyl group in the structure as represented by the following formula (a) such that the system is changed into a basic system when the system is acidic and the system is changed into an acidic system when the system is basic to combine the decomposed polymer and the functional molecule, thereby obtaining a modified polymer having an alkoxysilyl group introduced in at least one molecular terminal;

wherein R 6 represents an alkyl group having from 1 to 10 carbon atoms, R 7 represents an aldehyde group or a carbonyl group, R 8 represents an alkyl group having from 1 to 10 carbon atoms, m is a number of from 1 to 3, n is a number of 1 or 2, and 1 is a number of from 0 to 2.

7. The method for producing a modified polymer according to claim 6 , wherein the decomposed polymer contains a structure as represented by the following formula (11) in a terminal;

wherein R 9 represents a hydrogen atom or a methyl group.

8. The method for producing a modified polymer according to claim 6 , wherein the functional molecule having the alkoxysilyl group in the structure as represented by the formula (a) is obtained by oxidative cleavage of a carbon-carbon double bond in the functional molecule having at least one vinyl group.

9. The method for producing a modified polymer according to claim 6 , which obtains a modified polymer having a terminal group as represented by the following formula (b) in at least one molecular terminal;

wherein R 6 represents an alkyl group having from 1 to 10 carbon atoms, R 7 represents an aldehyde group or a carbonyl group, R 8 represents an alkyl group having from 1 to 10 carbon atoms, m is a number of from 1 to 3, n is a number of 1 or 2, and 1 is a number of from 0 to 2.

10. A diene polymer in which a linking group containing at least one of bonding structures as represented by the following formulae (2) to (5) is present in the molecule and diene polymer chains are linked through the linking group:

wherein R 4 represents an alkyl group having from 1 to 10 carbon atoms.

11. A rubber composition for a tire comprising 100 parts by mass of a modified diene rubber component that is the diene polymer according to claim 10 and contains from 1 to 5 mol % of an alkoxysilyl group in the main chain, and from 5 to 150 parts by mass of a filler.

12. The rubber composition for a tire according to claim 11 , wherein the modified diene rubber is a modified isoprene rubber having polyisoprene chains as represented by the following formula (9) linked through the linking group;

wherein n is an integer of 1 or more.

13. A diene polymer having a terminal group as represented by the following formula (b) in at least one molecular terminal of the diene polymer chain;

wherein R 6 represents an alkyl group having from 1 to 10 carbon atoms, R 7 represents an aldehyde group or a carbonyl group, R 8 represents an alkyl group having from 1 to 10 carbon atoms, m is a number of from 1 to 3, n is a number of 1 or 2, and 1 is a number of from 0 to 2, R 6 , R 7 , R 8 , m, n and 1 are the same as R 6 , R 7 , R 8 , m, n and 1 in the formula (a), respectively.

14. A rubber composition for a tire comprising 100 parts by mass of a modified diene rubber component that is the diene polymer according to claim 13 and contains from 0.01 to 5 mol % of an alkoxysilyl group, and from 5 to 150 parts by mass of a filler.

15. The rubber composition for a tire according to claim 14 , wherein the modified diene rubber is a modified isoprene rubber having polyisoprene chains as represented by the following formula (19) through a bonding structure as represented by any of the following formulae (12) to (15):

wherein R 6 represents an alkyl group having from 1 to 10 carbon atoms;

Assignees

• Toyo Tire & Rubber Co

Inventors

• Kawai Nobutomo

Classifications

• C08C19/08

  Depolymerisation · CPC title

• C08K3/22

  of metals · CPC title

• C08L15/005

  Hydrogenated nitrile rubber · CPC title

• C08K5/09

  Carboxylic acids; Metal salts thereof; Anhydrides thereof · CPC title

• C08L7/02

  Latex · CPC title