Method for producing modified conjugated diene polymer/copolymer, modified conjugated diene polymer/copolymer, and rubber composition and tire using the same

Patent metadata

Field	Value
Publication number	US-9623705-B2
Application number	US-92144809-A
Country	US
Kind code	B2
Filing date	Mar 10, 2009
Priority date	Mar 10, 2008
Publication date	Apr 18, 2017
Grant date	Apr 18, 2017

Abstract

The invention provides a method for producing a modified conjugated diene (co)polymer, the method including comprising: a modification reaction step including causing an organic silane compound to react with a conjugated diene (co)polymer having an active site at the active site, the organic silane compound having a characteristic group for forming a silanol group through hydrolysis and, in the vicinity of the characteristic group, (i) a functional group which binds the organic silane compound to the conjugated diene (co)polymer via addition to or substitution at the active site and which promotes reaction between the silanol group and a reinforcing filler after the addition or substitution reaction, or (ii) a functional group which promotes reaction between the silanol group and a reinforcing filler, and a hydrolyzation step performed after the modification reaction step; a modified conjugated diene (co)polymer having, at a molecular end of the conjugated diene (co)polymer, a silanol group, and a functional group in the vicinity of the silanol group, the functional group accelerating reaction between the silanol group and the reinforcing filler; a rubber composition containing the (co)polymer and carbon black having specific characteristics; and a tire formed from the rubber composition.

First claim

The invention claimed is:

1. A modified conjugated diene (co)polymer having, at a molecular end of the conjugated diene (co)polymer, a silanol group, and a functional group being within a distance from the silanol group equivalent to 1 to 20 carbon atoms, the functional group accelerating reaction between the silanol group and a reinforcing filler,
wherein the modified conjugated diene (co)polymer is produced by a method comprising:
a modification reaction step including causing a conjugated diene (co)polymer having an active site to react with an organic silane compound at the active site, the organic silane compound having a characteristic group for forming a silanol group through hydrolysis and, within a distance from the characteristic group equivalent to 1 to 20 carbon atoms, (i) a functional group which binds the organic silane compound to the conjugated diene (co)polymer via addition to or substitution at the active site and which promotes reaction between the silanol group and the reinforcing filler after the addition or substitution reaction, or (ii) a functional group which promotes reaction between the silanol group and the reinforcing filler, and
a hydrolyzation step performed after the modification reaction step,
wherein the characteristic group for forming the silanol group through hydrolysis is an alkoxysilane group, and 10% or more in number of the alkoxysilane groups form silanol groups through hydrolysis.

2. A modified conjugated diene (co)polymer represented by formula (3):

(wherein R 1 represents a single bond or a C1 to C20 divalent hydrocarbon group; each of R 2 and R 3 represents a hydrogen atom or a C1 to C20 monovalent hydrocarbon group; A 3 represents a functional group which promotes reaction between a silanol group and a reinforcing filler; and m is an integer of 1 to 10) or a modified conjugated diene (co)polymer represented by formula (4):

(wherein R 4 represents a single bond or a C1 to C20 hydrocarbon group; each of R 5 and R 6 represents a single bond, a hydrogen atom, or a C1 to C20 hydrocarbon group; A 4 represents a single bond, a C1 to C20 hydrocarbon group, or a functional group which promotes reaction between a silanol group and a reinforcing filler; each of B and D represents a group containing at least one functional group which promotes reaction between the silanol group and the reinforcing filler; each of p and q is an integer of 0 to 5; (p+q) is 1 or more; and n is an integer of 1 to 10),
wherein the modified conjugated diene (co)polymer is obtained by hydrolysis performed on a (co)polymer having alkoxysilane groups, wherein 68% or more in number of the alkoxysilane groups form silanol groups through hydrolysis.

3. A modified conjugated diene (co)polymer according to claim 2 , wherein each of the functional groups A 3 and A 4 in formula (3) or (4) which promote reaction between the silanol group and the reinforcing filler is at least one divalent functional group selected from among divalent functional groups having at least one member selected from among a (thio)ether bond, a (thio)urethane bond, an imino bond, and an amido bond; and divalent functional groups derived from a functional group selected from among a nitrile group, a pyridyl group, an N-alkylpyrrolidonyl group, an N-alkylimidazolyl group, an N-alkylpyrazolyl group, a (thio)ketone group, a (thio)aldehyde group, an isocyanuric acid triester residue, a C1 to C20 (thio)carboxylic acid hydrocarbyl ester residue, a C1 to C20 (thio)carboxylic acid metal salt residue, a C1 to C20 carboxylic anhydride residue, a C1 to C20 carboxyl halide residue, and a carbonic acid dihydrocarbyl ester residue.

4. A modified conjugated diene (co)polymer according to claim 2 or 3 , wherein each of B and D in formula (4) containing at least one functional group which promotes reaction between the silanol group and the reinforcing filler is at least one functional group selected from among a primary amino group, a secondary amino group, a protected primary or secondary amino group, a tertiary amino group, a cyclic amino group, an oxazolyl group, an imidazolyl group, an aziridinyl group, a (thio)ketone group, a (thio)aldehyde group, an amido group, a (thio)epoxy group, a (thio)isocyanato group, a nitrile group, a pyridyl group, an N-alkylpyrrolidonyl group, an N-alkylimidazolyl group, an N-alkylpyrazolyl group, an imino group, an amido group, a ketimine group, an imine residue, an isocyanuric acid triester residue, a C1 to C20 (thio)carboxylic acid hydrocarbyl ester residue, a C1 to C20 (thio)carboxylic acid metallic salt residue, a C1 to C20 carboxylic anhydride residue, a C1 to C20 carboxyl halide residue, a carbonic acid dihydrocarbyl ester residue, and functional groups represented by formula -E-F-G (wherein E represents an imino group, a divalent imine residue, a divalent pyridine residue, or a divalent amide residue; F represents a C1 to C20 alkylene group, a phenylene group, or a C8 to C20 aralkylene group; and G represents a primary amino group, a secondary amino group, a protected primary or secondary amino group, a tertiary amino group, a cyclic amino group, an oxazolyl group, an imidazolyl group, an aziridinyl group, a ketimine group, a nitrile group, an amido group, a pyridine group, or a (thio)isocyanato group).

5. A rubber composition comprising a modified conjugated diene (co)polymer as recited in claim 1 .

6. A rubber composition according to claim 5 , which further contains a condensation-accelerating agent.

7. A pneumatic tire formed from a rubber composition as recited in claim 5 .

8. A rubber composition characterized by comprising 100 parts by mass of a rubber ingredient containing (A) a modified conjugated diene (co)polymer as recited in claim 1 or 2 , and 10 to 100 parts by mass of (B) carbon black having a nitrogen adsorption specific surface area (N 2 SA) of 20 to 100 m 2 /g.

9. A rubber composition according to claim 8 , wherein the modified conjugated diene (co)polymer (A) is a modified conjugated diene-based polymer (a-1) having a structure represented by formula (11):

(wherein R 21 represents a C1 to C20 hydrocarbyl group and R 22 represents a C1 to C12 alkylene group) and/or a modified conjugated diene-based polymer (a-2) having a structure represented by formula (12):

(wherein R 23 represents a C1 to C20 hydrocarbyl group; R 24 represents a C1 to C12 alkylene group; R 25 represents a C1 to C20 hydrocarbyl group, a C2 to C20 hydrocarbylcarboxyl group, a —OH group, or a C5 to C20 1,3-dicarbonyl-containing group; when a plurality of R 25 are present, they may be identical to or different from one another; M represents Ti, Sn, Al, Si, or Bi; k is (valence of M)−2; and n is 1).

10. A rubber composition according to claim 8 , wherein the modified conjugated diene (co)polymer (A) is a modified conjugated diene-based polymer (a-1) having an end structure represented by formula (11):

(wherein R 21 represents a C1 to C20 hydrocarbyl group and R 22 represents a C1 to C12 alkylene group), which is produced by causing a compound containing a bi-functional silicon atom to which one hydrocarbyloxy group and one reactive group are directly bonded and to which one pro

Assignees

• Tanaka Ken
• Mori Noriko
• Itoh Yuki
• Ozawa Yoichi
• Nakagawa Ryuji
• Matsushita Junko
• Matsuo Shigeaki
• Masaki Kouji
• Shiraishi Fumihiro
• Oota Fuminori
• Bridgestone Corp

Inventors

• Tanaka Ken
• Mori Noriko
• Itoh Yuki
• Ozawa Yoichi
• Nakagawa Ryuji
• Matsushita Junko
• Matsuo Shigeaki
• Masaki Kouji
• Shiraishi Fumihiro
• Oota Fuminori

Classifications

• C08C19/00

  Chemical modification of rubber · CPC title

• C08K5/098

  Metal salts of carboxylic acids · CPC title

• C08L21/00

  Compositions of unspecified rubbers · CPC title

• C08L7/00

  Compositions of natural rubber · CPC title

• C08K5/057

  Metal alcoholates {(metal enolates C08K5/0091)} · CPC title