Rubber composition and pneumatic tire

Patent metadata

Field	Value
Publication number	US-9315647-B2
Application number	US-201213982160-A
Country	US
Kind code	B2
Filing date	Mar 23, 2012
Priority date	Mar 25, 2011
Publication date	Apr 19, 2016
Grant date	Apr 19, 2016

Abstract

The present invention provides a rubber composition that can enhance the fuel economy, wet-grip performance, abrasion resistance, and processability in a balanced manner, and also provides a pneumatic tire using this rubber composition. The present invention relates to a rubber composition that contains a rubber component, silica, and a compound represented by formula (1) below, wherein the rubber component contains, based on 100% by mass of the rubber component, not less than 5% by mass of a conjugated diene polymer containing a constituent unit based on a conjugated diene and a constituent unit represented by formula (I) below, at least one terminal of the polymer being modified with a specific compound; and an amount of the silica is 5 to 150 parts by mass per 100 parts by mass of the rubber component.

First claim

The invention claimed is:

1. A rubber composition, comprising a rubber component, silica, and a processing aid compound represented by formula (1) below,
wherein the rubber component contains, based on 100% by mass of the rubber component, not less than 5% by mass of a conjugated diene polymer containing a constituent unit based on a conjugated diene and a constituent unit represented by formula (I) below,
at least one terminal of the polymer being modified with at least one compound selected from the group consisting of a compound represented by formula (II) below, a compound containing a group represented by formula (III) below, a compound represented by formula (IV) below, a silicon compound containing at least one of a group represented by formula (V) below and a group represented by formula (VI) below, and a compound containing a group represented by formula (VII) below,
wherein the silica is present in an amount of 5 to 150 parts by mass per 100 parts by mass of the rubber component,
formula (I):

wherein X 1 , X 2 , and X 3 each independently represent a group represented by formula (Ia) below, a hydroxy group, a hydrocarbyl group, or a substituted hydrocarbyl group, and at least one of X 1 , X 2 , and X 3 is a hydroxy group or a group represented by the following formula (Ia):

wherein R 1 and R 2 each independently represent a C 1-6 hydrocarbyl group, a C 1-6 substituted hydrocarbyl group, a silyl group, or a substituted silyl group, and R 1 and R 2 may be bonded to each other to form a cyclic structure together with the nitrogen atom;
formula (II):

wherein n represents an integer of 1 to 10; R 11 , R 12 , and R 13 each independently represent a C 1-4 hydrocarbyl group or a C 1-4 hydrocarbyloxy group, and at least one of R 11 , R 12 , and R 13 is the hydrocarbyloxy group; and A 1 represents a nitrogen atom-bearing functional group;
formula (III):

wherein p represents an integer of 0 or 1; T represents a C 1-20 hydrocarbylene group or a C 1-20 substituted hydrocarbylene group; and A 2 represents a nitrogen atom-bearing functional group;
formula (IV):

wherein g represents an integer of 1 to 10; R 21 represents a hydrogen atom, a C 1-6 hydrocarbyl group, or a C 1-6 substituted hydrocarbyl group; A 3 represents an oxygen atom or the following group: —NR 22 — where R 22 represents a hydrogen atom or a C 1-10 hydrocarbyl group; and A 4 represents a functional group bearing at least one of a nitrogen atom and an oxygen atom;
formulas (V), (VI) and (VII):

wherein w represents an integer of 1 to 11, and A 5 represents a nitrogen atom-bearing functional group;
formula (1):

wherein R 101 represents a hydrogen atom, a branched or unbranched C 1-30 alkyl group, a branched or unbranched C 2-30 alkenyl group, a branched or unbranched C 6-30 aryl group, or a hydroxy group; R 102 and R 103 are the same as or different from each other and each represent a hydrogen atom, a branched or unbranched C 1-30 alkyl group, a branched or unbranched C 2-30 alkenyl group, a branched or unbranched C 2-30 alkynyl group, a branched or unbranched C 6-30 aryl group, or a group represented by formula (2) below, wherein a hydrogen atom of the alkyl group, alkenyl group, alkynyl group, or aryl group may be substituted by a hydroxy group or a carboxyl group; a pair of R 101 and R 102 , a pair of R 101 and R 103 , or a pair of R 102 and R 103 may form a cyclic structure; and d 1 is zero,

wherein R 104 represents a branched or unbranched C 1-30 alkylene group; R 105 represents a hydrogen atom, a branched or unbranched C 1-30 alkyl group, a branched or unbranched C 2-30 alkenyl group, a branched or unbranched C 6-30 aryl group, or a hydroxy group; and d 2 represents an integer of 0 to 10.

2. The rubber composition according to claim 1 , wherein R 1 and R 2 in formula (Ia) are C 1-6 hydrocarbyl groups.

3. The rubber composition according to claim 1 , wherein two of X 1 , X 2 , and X 3 in formula (I) are selected from a group represented by formula (Ia) and a hydroxy group.

4. The rubber composition according to claim 1 , wherein A 1 in formula (II) is a group represented by the following formula (IIa):

wherein R 14 and R 15 each independently represent a C 1-6 group optionally containing at least one atom selected from the group consisting of a nitrogen atom, an oxygen atom, and a silicon atom, R 14 and R 15 may be bonded to each other to form a cyclic structure together with the nitrogen atom, and R 14 and R 15 may form a single group bonded to the nitrogen via a double bond.

5. The rubber composition according to claim 1 ,
wherein the group represented by formula (III) is a group represented by the following formula (IIIa):

6. The rubber composition according to claim 5 , wherein the compound containing a group represented by formula (III) is at least one compound selected from the group consisting of a compound represented by formula (IIIa-1) below, a compound represented by formula (IIIa-2) below, and a compound represented by formula (IIIa-3) below,

wherein R 31 represents a hydrogen atom, a C 1-10 hydrocarbyl group, a C 1-10 substituted hydrocarbyl group, or a heterocyclic group containing at least one of a nitrogen atom and an oxygen atom as a heteroatom; and R 32 and R 33 each independently represent a C 1-10 group optionally containing at least one atom selected from the group consisting of a nitrogen atom, an oxygen atom, and a silicon atom, R 32 and R 33 may be bonded to each other to form a cyclic structure together with the nitrogen atom, and R 32 and R 33 may form a single group bonded to the nitrogen via a double bond;

wherein e represents an integer of 0 to 10, and R 34 and R 35 each independently represent a C 1-20 hydrocarbyl group or a C 1-20 substituted hydrocarbyl group;

wherein f represents an integer of 0 to 10, and R 36 represents a C 1-20 hydrocarbyl group or a C 1-20 substituted hydrocarbyl group.

7. The rubber composition according to claim 1 , wherein the compound containing a group represented by formula (III) is a compound represented by the following formula (IIIb-1):

wherein R 37 represents a hydrogen atom, a C 1-10 hydrocarbyl group, a C 1-10 substituted hydrocarbyl group, or a het

Assignees

• Imoto Yoji
• Uesaka Kenichi
• Taguchi Takafumi
• Omura Naoya
• Kunisawa Tetsuya
• Yamauchi Satomi
• Sumitomo Rubber Ind

Inventors

• Imoto Yoji
• Uesaka Kenichi
• Taguchi Takafumi
• Omura Naoya
• Kunisawa Tetsuya
• Yamauchi Satomi

Classifications

• C08K3/36 Primary

  Silica · CPC title

• B60C1/0016

  Compositions of the tread · CPC title

• C08F230/08

  containing silicon · CPC title

• C08L15/00

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

• C08K5/16

  Nitrogen-containing compounds {(C08K5/0091 takes precedence)} · CPC title