Method for manufacturing rubber composition

Patent metadata

Field	Value
Publication number	US-9688825-B2
Application number	US-201113876983-A
Country	US
Kind code	B2
Filing date	Oct 3, 2011
Priority date	Oct 1, 2010
Publication date	Jun 27, 2017
Grant date	Jun 27, 2017

Abstract

The present invention relates to a method for producing a rubber composition containing a rubber component (A) of at least one selected from natural rubbers and synthetic dienic rubbers, a filler containing an inorganic filler (B), a silane coupling agent (C) and at least one vulcanization promoter (D) selected from guanidines, sulfenamides, thiazoles, thiurams, dithiocarbamate salts, thioureas and xanthate salts, wherein the rubber composition is kneaded in at least three stages, in the first stage (X) of kneading, the rubber component (A), all or a part of the inorganic filler (B), and all or a part of the silane coupling agent (C) are kneaded, then in the stage (Y) on and after the second stage of kneading but before the final stage, the vulcanization promoter (D) is added and kneaded, and in the final stage (Z) of kneading, a vulcanizing agent is added and kneaded.

First claim

The invention claimed is:

1. A method for producing a rubber composition containing a rubber component (A) of at least one selected from the group consisting of natural rubbers and synthetic dienic rubbers, a filler containing an inorganic filler (B), a silane coupling agent (C) and at least one vulcanization promoter (D) selected from the group consisting of guanidines, sulfenamides thiazoles, thiruams, dithiocarbamate salts, thioureas and xanthate salts, wherein the rubber composition is kneaded in at least three stages, in the first stage (X) of kneading, the rubber component (A), all or part of the inorganic filler (B), and all or a part of the silane coupling agent (C) are kneaded, then in the stage (Y) on and after the second stage of kneading but before the final stage, the vulcanization promoter (D) is added and kneaded, and in the final stage (Z) of kneading, a vulcanizing agent is added and kneaded,
wherein the highest temperature of the rubber composition in stage (Y) of kneading is 120 to 190° C. and wherein the highest temperature of the rubber composition in the first stage (X) of kneading is from 140 to 190° C., and
wherein the number of molecules of the vulcanization promoter (D) in the rubber composition in the stage (Y) of kneading is from 0.1 to 1.0 time the number of molecules of the silane coupling agent (C) therein.

2. The method for producing a rubber composition according to claim 1 , wherein the silane coupling agent (C) is at least one compound selected from a group consisting of compounds represented by the following general formulae (I) to (IV):
[Chemical Formula 1]
(R 1 O) 3-p (R 2 ) p Si—R 3 —S a —R 3 —Si(OR 1 ) 3-r (R 2 ) r   (I)

wherein multiple R 1 's may be the same or different, each representing a linear, cyclic or branched alkyl group having from 1 to 8 carbon atoms, a linear or branched alkoxylalkyl group having from 2 to 8 carbon atoms, or a hydrogen atom; multiple R 2 's may be the same or different, each representing a linear, cyclic or branched alkyl group having from 1 to 8 carbon atoms; multiple R 3 's may be the same or different, each representing a linear or branched alkylene group having from 1 to 8 carbon atoms; a indicates from 2 to 6 as a mean value; p and r may be the same or different, each indicating from 0 to 3 as a mean value, provided that both p and r are not 3 at the same time;

wherein R 4 represents a monovalent group selected from the group consisting of —Cl, —Br, R 9 O—, R 9 C(═O)O—, R 9 R 10 C═NO—, R 9 R 10 CNO—, R 9 R 10 N—, and —(OSiR 9 R 10 ) h (OSiR 9 R 10 R 11 ) where R 9 , R 10 and R 11 each represents a hydrogen atom or a monovalent hydrocarbon group having from 1 to 18 carbon atoms; and h indicates from 1 to 4 as a mean value; R 5 represents R 4 , a hydrogen atom, or a hydrocarbon group having from 1 to 18 carbon atoms; R 6 represents R 4 , R 5 , a hydrogen atom, or a group —[O(R 12 O) j ] 0.5 where R 12 represents an alkylene group having from 1 to 18 carbon atoms; and j indicates an integer of from 1 to 4; R 7 represents a divalent hydrocarbon group having from 1 to 18 carbon atoms; R 8 represents a monovalent hydrocarbon group having from 1 to 18 carbon atoms; x, y and z each indicates a number satisfying the relationship of x+y+2z=3, 0≦x≦3, 0≦y≦2, 0≦z≦1;
[Chemical Formula 3]
(R 13 O) 3-s (R 14 ) s S—R 15 —S k —R 16 —S k —R 15 —Si(OR 13 ) 3-t (R 14 ) t   (III)

wherein multiple R 13 's may be the same or different, each representing a linear, cyclic or branched alkyl group having from 1 to 8 carbon atoms, a linear or branched alkoxylalkyl group having from 2 to 8 carbon atoms, or a hydrogen atom; multiple R 14 's may be the same or different, each representing a linear, cyclic or branched alkyl group having from 1 to 8 carbon atoms; multiple R 15 's may be the same or different, each representing a linear or branched alkylene group having from 1 to 8 carbon atoms; R 16 represents a divalent group of a general formula —S—R 17 —S—, —R 18 —S m1 —R 19 — or —R 20 —S m2 —R 21 —S m3 —R 22 — where R 17 to R 22 each represents a divalent hydrocarbon group, a divalent aromatic group or a divalent organic group containing a hetero element except sulfur and oxygen, having from 1 to 20 carbon atoms; m1, m2 and m3 may be the same or different, each indicating from 1 to less than 4 as a mean value; multiple k's may be the same or different, each indicating from 1 to 6 as a mean value; s and t each indicates from 0 to 3 as a mean value, provided that both s and t are not 3 at the same time;

wherein R 23 represents a linear, branched or cyclic alkyl group having from 1 to 20 carbon atoms; multiple G's may be the same or different, each representing an alkanediyl group or an alkenediyl group having from 1 to 9 carbon atoms; multiple Z a 's may be the same or different, each representing a functional group capable of bonding to the two silicon atoms and selected from [—O—] 0.5 , [—O-G-] 0.5 and [—O-G-O—] 0.5 ; multiple Z b 's may be the same or different, each representing a functional group capable of bonding to the two silicon atoms and represented by [—O-G-O—] 0.5 ; multiple Z c 's may be the same or different, each representing a functional group selected from —Cl, —Br, —OR a , R a C(═O)O—, R a R b C═NO—, R a R b N—, R a — and HO-G-O— where G is the same as above; R a and R b each represents a linear, branched or cyclic alkyl group having from 1 to 20 carbon atoms; m, n, u, v and w each is 1≦m≦20, 0≦n≦20, 0≦u≦3, 0≦v≦2, 0≦w≦1, and (u/2)+v+2w is 2 or 3; in case where the formula has multiple A's, then Z a u , Z b v and Z c w may be the same or different in those multiple A's; in case where the formula has multiple B's, then Z a u , Z b v and Z c w may be the same or different in those multiple B's.

3. The method for producing a rubber composition according to claim 2 , wherein the silane coupling agent (C) is a compound represented by the general formula (I).

4. The method for producing a rubber composition according to claim 1 , wherein the inorganic filler (B) is silica.

5. The method for producing a rubber composition according to claim 1 , wherein the inorganic filler (B) accounts for at least 30% by mass of the filler.

6. The method for producing a rubber composition according to claim 1 , wherein the guanidine is at least one compound selected from the group consisting of 1,3-diphenylguanidine, 1,3-di-o-tolylguanidine and 1-o-tolylbiguanide.

7. The method for producing a rubber composition according to claim 1 , wherein the sulfenamide is at least one compound selected from the group consisting of N-cyclohexyl-2-benzothiazolylsulfenamide and N-tert-butyl-2-benzothiazolylsulfenamide.

8. The method for producing a rubber composition according to claim 1 , wherein the thiazole is at least one compound selected from the group consisting of 2-mercaptobenzothiazole and di-2-benzothiazolyl disulfide.

9. The method for producing a rubber composition according to claim 1 , wherein the thiuram is at least one compound selected from the group consisting of tetrakis(2-ethylhexyl)thiuram disulfide and tetrabenzylthiuram disulfide.

10. The method for producing a rubber composition according to claim 1 , wherein the thiourea is at least one compound selected from the group consisting of N,N′-diethylthiourea, trimethylthiourea, N,N′-diphenylthiourea and N,N′-dimethylthiourea.

11. The method for producing a rubber composition according to claim 1 , wherein the dithiocarbamate salt is at

Assignees

• Katou Seiichi
• Horie Satoshi
• Bridgestone Corp

Inventors

• Katou Seiichi
• Horie Satoshi

Classifications

• C08L7/00 Primary

  Compositions of natural rubber · CPC title

• C08K5/39

  Thiocarbamic acids; Derivatives thereof, e.g. dithiocarbamates · CPC title

• C08J2309/00

  Characterised by the use of homopolymers or copolymers of conjugated diene hydrocarbons · CPC title

• C08J3/20 Primary

  Compounding polymers with additives, e.g. colouring · CPC title

• C08K5/47

  Thiazoles · CPC title