Rubber composition, rubber product and tire

Abstract

The present invention provides a rubber composition suitable for use in tire manufacturing, comprising a functionalized polymer and a functionalized silica.

Description

Technical Field

[0001] The present invention provides a rubber composition suitable for tire manufacturing, which includes a functionalized polymer and a functionalized silica. The present invention also provides rubber products and tires made from these rubber compositions. Background Art

[0002] As the world moves towards reducing carbon dioxide emissions, the demand for low fuel consumption vehicles is growing. In order to respond to this demand, tires need lower rolling resistance. From the viewpoint of improving automobile driving safety, it is also important to ensure that the grip performance (wet road performance) on wet roads is maximized. Wear resistance and toughness are other important factors for improving tire manufacturing. Tire manufacturers can change the components of the rubber composition from which tires are prepared to affect these properties. Functionalized polymers known in the art include those disclosed in WO 2014 / 173706 A1. In addition, functionalized fillers are known, such as those disclosed in WO 2015 / 121333 A1.

[0003] When developing a rubber composition for tire tread to improve the rolling resistance of a tire, it is generally effective to regard the loss tangent (tan δ) close to 60°C as an index. Specifically, as described in JP 2012-92179 A, ​​a rubber composition with a low tan δ close to 60°C in a tread rubber can suppress the heat generation in the tire to reduce the rolling resistance, thereby improving the fuel efficiency of the tire. Similarly, JP 2014-9324 A discloses a technology for improving the wet road performance of a rubber composition for tire treads. Wear resistance and toughness can also be measured by techniques known in the art. Wet road performance, rolling resistance and wear resistance are together referred to as the magic triangle of viscoelasticity. It is desirable in the art to provide a tire in which all these properties are improved. Summary of the invention

[0004] The present inventors have unexpectedly discovered that by providing a rubber composition comprising a polymer functionalized with one or more carboxyl groups and a silica functionalized with one or more carboxyl groups, a tire made from the rubber composition has excellent wear resistance, rolling resistance, wet road performance and toughness, and an excellent balance between these properties. In particular, an interactive and / or synergistic effect is observed on the viscoelastic properties of rubber products prepared from a rubber composition comprising a functionalized polymer and a functionalized silica.

[0005] A first aspect of the present invention provides a rubber composition comprising:

[0006] a rubber component comprising an end-functionalized solution polymerized styrene-butadiene (SSBR) copolymer, wherein the end-functionalized SSBR copolymer comprises terminal carboxyl groups; and,

[0007] Functionalized silica, wherein the functionalized silica is silica functionalized with one or more carboxyl groups, the functionalized silica having:

[0008] -BET specific surface area is 250~310m 2 / g;

[0009] -CTAB specific surface area is 230~285m 2 / g

[0010] - a carbon content (C) of at least 0.10% by weight of the functionalized silica;

[0011] - an object size distribution width ratio (Ld) of at least 0.91; and,

[0012] - The pore volume distribution ratio is at least 0.65.

[0013] The end-group functionalized solution polymerized styrene-butadiene (SSBR) copolymer may include a terminal silane-containing carboxyl group of formula (I):

[0014]

[0015] in:

[0016] R 1 and R 2 are the same or different and are each independently hydrogen, alkyl, alkoxy, cycloalkyl, cycloalkoxy, aryl, aryloxy, alkylaryl, alkylaryloxy, aralkyl, or aralkyloxy, which may contain one or more heteroatoms, preferably wherein the heteroatoms are one or more selected from the group consisting of O, N, S and Si;

[0017] R 3 and R 4 are the same or different and are each independently hydrogen, alkyl, cycloalkyl, aryl, alkaryl, or aralkyl, which may contain one or more heteroatoms, preferably wherein the heteroatoms are one or more selected from the group consisting of O, N, S and Si; and,

[0018] A is a divalent organic group, which can be an alkyl group; selected from O, NR 7 , S and SiR 8 R 9 or an alkyl group containing one or more heteroatoms, wherein the heteroatoms are preferably selected from O, NR 7 , S, and SiR 8 R 9 One or more of the groups consisting of.

[0019] The carboxyl groups containing the silane may be present as carboxylates of formula (II):

[0020]

[0021] in:

[0022] R 1 and R 2 As defined in formula (I) above;

[0023] R 3 and R 4 As defined in formula (I) above; and

[0024] A is as defined in formula (I) above; and

[0025] M is a 1-4-valent metal or semimetal, preferably Li, Na, K, Mg, Ca, Zn, Fe, Co, Ni, Al, Nd, Ti, Sn, Si, Zr, V, Mo or W.

[0026] n is an integer of 1 to 4.

[0027] The end-functionalized SSBR copolymer can be obtained by reacting the SSBR copolymer with one or more functionalizing agents in the form of silicone lactones. For example, the silicone lactone can be a compound of formula (III):

[0028]

[0029] in

[0030] R 1 and R 2 As defined in formula (I) above;

[0031] R 3 and R 4 As defined in formula (I) above; and

[0032] A is as defined above in formula (I).

[0033] The silane-containing carboxyl groups may be bonded to the SSBR copolymer via one or more divalent structural units of formula (V):

[0034]

[0035] in

[0036] n is an integer from 3 to 6;

[0037] R 5 , R 6 are the same or different and are each independently hydrogen, alkyl, cycloalkyl, aryl, alkaryl, or aralkyl;

[0038] It may contain one or more heteroatoms, and preferably the heteroatoms are one or more selected from the group consisting of O, N, S or Si.

[0039] The divalent structural unit of formula (V) may be derived from a cyclosiloxane. For example, a cyclosiloxane derived from formula (IV):

[0040]

[0041] in

[0042] n is an integer from 3 to 6;

[0043] R 5 , R 6 are the same or different and are each independently hydrogen, alkyl, cycloalkyl, aryl, alkaryl, or aralkyl;

[0044] It may contain one or more heteroatoms, preferably wherein the heteroatoms are one or more selected from the group consisting of O, N, S, or Si, more preferably wherein the divalent structural unit of formula (V) may be derived from one or more cyclosiloxanes selected from the group consisting of hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, and dodecamethylcyclohexasiloxane.

[0045] Functionalized silica may include silica functionalized with one or more carboxyl groups on its surface. The carboxyl groups may be present in the form of carboxylic acids and / or carboxylates.

[0046] The carboxyl groups of the functionalized silica may be derived from one or more carboxylic acids, such as one or more polycarboxylic acids. The one or more polycarboxylic acids may contain two, three, four, or more than four carboxyl groups. Preferably, the one or more polycarboxylic acids may be one or more selected from the group consisting of adipic acid, succinic acid, ethylsuccinic acid, glutaric acid, methylglutaric acid, oxalic acid, and citric acid.

[0047] The carboxyl groups of the functionalized silica can be obtained by reacting silica with one or more carboxylic acids to form the functionalized silica.

[0048] The Brunauer-Emmett-Teller (BET) specific surface area of ​​functionalized silica is 250-310 m 2 / g. The Brunauer-Emmett-Teller (BET) specific surface area may preferably be 270 to 300 m 2 / g, more preferably 280 to 290 m 2 / g.

[0049] The surface area of ​​the functionalized silica by adsorption of cetyltrimethylammonium bromide (CTAB) is 230 m2 / g~285m 2 / g. The surface area adsorbed by cetyltrimethylammonium bromide (CTAB) can be 240m 2 / g~270m 2 / g, more preferably 245m 2 / g~265m 2 / g, more preferably 250m 2 / g~260m 2 / g.

[0050] The carbon content of the functionalized silica is at least 0.10 wt % of the functionalized silica. The carbon content may preferably be at least 0.15 wt %, more preferably at least 0.20 wt %, more preferably at least 0.25 wt %, more preferably at least 0.30 wt % of the functionalized silica.

[0051] The object size distribution width ratio Ld of the functionalized silica is at least 0.91. The object size distribution width ratio Ld is preferably at least 0.94.

[0052] The pore volume distribution ratio of the functionalized silica is at least 0.65. The pore volume distribution is preferably at least 66, more preferably at least 0.68.

[0053] The pH of the functionalized silica may be 2.5 to 7, preferably 2.5 to 5, more preferably 3 to 4.5.

[0054] The ratio of the amount of functionalized silica in parts by weight relative to 100 parts by weight of the rubber component to the amount of the end-functionalized SSBR copolymer in parts by weight relative to 100 parts by weight of the rubber component can be 0.5:1 to 2:1, preferably 0.75:1 to 1.50:1, preferably 0.9:1 to 1.40:1, more preferably 0.95:1 to 1.35:1.

[0055] The rubber composition may include:

[0056] 10.5 to 100 parts by weight of a terminal functionalized SSBR copolymer relative to 100 parts by weight of the rubber component; and,

[0057] Relative to 100 parts by weight of the rubber component, 20 to 200 parts by weight of the functionalized silica.

[0058] The rubber composition may preferably include:

[0059] 40 to 90 parts by weight of a terminal functionalized SSBR copolymer relative to 100 parts by weight of the rubber component; and,

[0060] Relative to 100 parts by weight of the rubber component, 50 to 100 parts by weight of the functionalized silica.

[0061] The rubber composition may preferably include:

[0062] 50 to 80 parts by weight of a terminal functionalized SSBR copolymer relative to 100 parts by weight of the rubber component; and,

[0063] Relative to 100 parts by weight of the rubber component, 65 to 85 parts by weight of the functionalized silica.

[0064] The rubber composition may preferably include:

[0065] 55 to 75 parts by weight of a terminal functionalized SSBR copolymer relative to 100 parts by weight of the rubber component; and,

[0066] Relative to 100 parts by weight of the rubber component, 70 to 75 parts by weight of the functionalized silica.

[0067] In particular embodiments, the rubber composition may include:

[0068] 60 parts by weight of a terminal functionalized SSBR copolymer relative to 100 parts by weight of the rubber component; and,

[0069] Relative to 100 parts by weight of the rubber component, 72 parts by weight of the functionalized silica.

[0070] In particular embodiments, the rubber composition may include:

[0071] 70 parts by weight of a terminal functionalized SSBR copolymer relative to 100 parts by weight of the rubber component; and,

[0072] Relative to 100 parts by weight of the rubber component, 72 parts by weight of the functionalized silica.

[0073] In particular embodiments, the rubber composition may include:

[0074] 70 parts by weight of a terminal functionalized SSBR copolymer relative to 100 parts by weight of the rubber component; and,

[0075] Relative to 100 parts by weight of the rubber component, 80 parts by weight of the functionalized silica.

[0076] The rubber composition of the present invention may be compounded.

[0077] A second aspect of the present invention relates to a rubber product comprising the rubber composition of the present invention, wherein the rubber composition is vulcanized.

[0078] A third aspect of the present invention relates to a tire including the rubber composition of the present invention or the rubber product of the present invention. DETAILED DESCRIPTION

[0079] According to one aspect, the present invention provides a rubber composition comprising:

[0080] a rubber component comprising an end-functionalized solution polymerized styrene-butadiene (SSBR) copolymer, wherein the end-functionalized SSBR copolymer comprises terminal carboxyl groups; and,

[0081] Functionalized silica, wherein the functionalized silica is silica functionalized with one or more carboxyl groups, the functionalized silica having:

[0082] -BET surface area is between 250 and 310 m 2 / g between;

[0083] -CTAB specific surface area is between 230 and 285 m 2 / g

[0084] - a carbon content of at least 0.10% by weight of the functionalized silica;

[0085] - an object size distribution width ratio Ld of at least 0.91; and,

[0086] - The pore volume distribution ratio is at least 0.65.

[0087] Compared with rubber compositions known in the art, rubber compositions of the present invention provide many advantages. In particular, the tire manufactured by the rubber composition of the present invention has excellent wet road performance, rolling resistance, wear resistance and toughness and excellent balance between these properties. The combination of end-functionalized SSBR copolymer and functionalized silica has interaction and / or synergistic influence on the performance of the rubber composition, and produces the favorable performance of the tire discussed above. Specifically, the interaction (which can be synergistic) between end-functionalized SSBR copolymer and functionalized silica causes filler (especially, functionalized silica filler) to reach unprecedented dispersion level in rubber compositions of the present invention and rubber products. This unprecedented dispersibility has a positive impact on the wet road performance, rolling resistance, wear resistance and toughness of the tire manufactured by the rubber composition, and provides excellent balance between these properties.

[0088] End-functionalized solution-polymerized styrene-butadiene (SSBR) copolymers

[0089] The end-functionalized SSBR copolymer may include a SSBR copolymer terminated by a silane-containing carboxyl group of formula (I):

[0090]

[0091] in:

[0092] R 1 and R 2 are the same or different and are each independently hydrogen, alkyl, alkoxy, cycloalkyl, cycloalkoxy, aryl, aryloxy, alkylaryl, alkylaryloxy, aralkyl, or aralkyloxy, which may contain one or more heteroatoms, preferably wherein the heteroatoms are one or more selected from the group consisting of O, N, S and Si;

[0093] R 3 and R 4 are the same or different and are each independently hydrogen, alkyl, cycloalkyl, aryl, alkaryl, or aralkyl, which may contain one or more heteroatoms, preferably wherein the heteroatoms are one or more selected from the group consisting of O, N, S and Si; and,

[0094] A is a divalent organic group, which can be an alkyl group; selected from O, NR 7 , S and SiR 8 R 9 or an alkyl group containing one or more heteroatoms, wherein the heteroatoms are preferably selected from O, NR 7 , S, and SiR 8 R 9 One or more of the groups consisting of.

[0095] The end-functionalized SSBR copolymer may include a SSBR copolymer terminated by a silane-containing carboxyl group of formula (I), wherein R 1 and R 2 are independently hydrogen, C 1 ~C 12 Straight or branched alkyl, C 2 ~C 12 Straight or branched alkenyl, C 1 ~C 12 Straight chain or branched alkoxy, C 3 ~C 12 Cycloalkyl, C 2 ~C 12 Cycloalkoxy, C 6 ~C 12 Aryl, C 6 ~C 12 Aryloxy, C 7 ~C 14 Aralkyl, C 7 ~C 14 Alkyl aryl, C 6 ~C 24 Alkyl aryloxy, C 5 ~C 24 Arylalkyl, or C 6 ~C24 Preferably, R 1 and R 2 Can be independently C 1 ~C 6 Straight or branched alkyl, C 2 ~C 6 Straight or branched alkenyl, C 1 ~C 6 Straight chain or branched alkoxy, C 3 ~C 12 Cycloalkyl, C 2 ~C 12 Cycloalkoxy, or C 6 ~C 12 Preferably, R 1 and R 2 Can be independently C 1 ~C 6 Straight or branched alkyl, C 2 ~C 6 Straight or branched alkenyl, C 1 ~C 6 Straight chain or branched chain alkoxy, or C 6 ~C 12 Preferably, R 1 and R 2 Can be independently C 1 ~C 3 Straight or branched alkyl, C 2 ~C 3 Straight or branched alkenyl, C 1 ~C 3 Straight chain or branched chain alkoxy, or C 6 Aryl. For example, R 1 and R 2 R may independently be methyl, tert-butyl, prop-1-enyl, ethoxy, or phenyl. More preferably, R 1 and R 2 It is methyl.

[0096] R 3 and R 4 can be independently hydrogen, C 1 ~C 12 Straight or branched alkyl, C 3 ~C 12 Cycloalkyl, C 6 ~C 12 Aryl, C 5 ~C 24 Arylalkyl, or C 5 ~C 24 Preferably, R 3 and R 4 can be independently hydrogen, C1 ~C 6 Straight or branched alkyl, C 2 ~C 6 Straight or branched alkenyl, C 1 ~C 6 Straight chain or branched chain alkoxy, or C 6 ~C 12 More preferably, R 3 and R 4 can be independently hydrogen or methyl. In a particular embodiment, R 3 / R 4 Together with A, it forms C 6 Aryl.

[0097] A can be independently substituted or unsubstituted C 1 ~C 6 Straight chain alkyl; selected from O, NR 7 , S and SiR 8 R 9 or independently selected from O, NR 7 , S and SiR 8 R 9 One or more heteroatoms in the group consisting of substituted or unsubstituted C 1 ~C 6 Preferably, A can be independently substituted or unsubstituted C 1 ~C 3 Straight chain alkyl; selected from O, NR 7 , S and SiR 8 R 9 or independently selected from O, NR 7 , S and SiR 8 R 9 One or more heteroatoms in the group consisting of substituted or unsubstituted C 1 ~C 3 Straight chain alkyl. When A is substituted, it can be selected from C 1 ~C 6 Straight chain alkyl and C 6 ~C 12 Preferably, A can be substituted by one or more of the group consisting of C 1 ~C 3 Straight chain alkyl or C 6 More preferably, A can be C 1 Group substitution. 7 It can be hydrogen, C 1 ~C 6Straight chain alkyl, for example, methyl or trimethylsilyl. 8 and R 9 Can be independently C 1 ~C 6 Preferably, A is a C containing S atom. 2 Alkyl. As a C containing S atom 2 The structure of A of the alkyl group is shown below.

[0098]

[0099] The carboxyl groups containing the silane may be present as carboxylates of formula (II):

[0100]

[0101] in:

[0102] R 1 and R 2 As defined in formula (I) above;

[0103] R 3 and R 4 As defined in formula (I) above; and

[0104] A is as defined above in formula (I); and

[0105] M is a 1-4 valent metal or semimetal, for example, Li, Na, K, Mg, Ca, Zn, Fe, Co, Ni, Al, Nd, Ti, Sn, Si, Zr, V, Mo or W.

[0106] n is an integer of 1 to 4.

[0107] In the compound of formula (II), M may be Li, and n may be 1.

[0108] R in formula (II) 1 , R 2 , R 3 , R 4 , R 7 , R 8 and R 9 The other definitions of are the same as those in the above formula (I).

[0109] The end-functionalized SSBR copolymer can be obtained by reacting the SSBR copolymer with one or more functionalizing agents in the form of silicone lactones. The silicone lactones can be compounds of formula (III):

[0110]

[0111] in

[0112] R 1 and R 2 As defined in formula (I) above;

[0113] R 3 and R 4 As defined in formula (I) above; and

[0114] A is as defined above in formula (I).

[0115] R in formula (III) 1 , R 2 , R 3 , R 4 , R 7 , R 8 and R 9 The other definitions of are as defined in the above formula (I).

[0116] Advantageously, the silyl lactone of formula (III) may be one or more selected from the group consisting of 2,2-dimethyl-1-oxa-2-silacyclohexane-6-one, 2,2,4-trimethyl-1-oxa-2-silacyclohexane-6-one, 2,2,5-trimethyl-1-oxa-2-silacyclohexane-6-one, 2,2,4,5-tetramethyl-1-oxa-2-silacyclohexane-6-one, 2,2-diethyl-1-oxa-2-silacyclohexane-8-one, 2,2-diethoxy-1-oxa-2-silacyclohexane-6-one, 2,2-dimethyl-1,4-dioxa-2-silacyclohexane-6-one, 2,2,5-trimethyl-1-oxa-2-silacyclohexane-6-one, 2,2,4,5-tetramethyl-1-oxa-2-silacyclohexane-6-one, -1,4-dioxa-2-silacyclohexane-6-one, 2,2,3,3-tetramethyl-1,4-dioxa-2-silacyclohexane-6-one, 2,2-dimethyl-1-oxa-4-thia-2-silacyclohexane-6-one, 2,2-diethyl-1-oxa-4-thia-2-silacyclohexane-6-one, 2,2-diphenyl-1-oxa-4-thia-2-silacyclohexane (silacyclonexan)-6-one, 2-methyl-2-vinyl-1-oxa-4-thia-2-silacyclohexane-6-one, 2,2,5-trimethyl-1-oxa-4-thia-2-silacyclohexane-6-one, 2,2-di methyl-1-oxa-4-aza-2-silacyclohexane-6-one, 2,2,4-trimethyl-1-oxa-4-aza-2-silacyclohexane-6-one, 2,4-dimethyl-2-phenyl-1-oxa-4-aza-2-silacyclohexane-6-one, 2,2-dimethyl-4-trimethylsilyl-1-oxa-4-aza-2-silacyclohexane-8-one, 2,2-diethoxy-4-methyl-1-oxa-4-aza-2-silacyclohexane-6-one, 2,2,4,4-tetramethyl-1-oxa-2,4-disilacyclohexane-8-one, 3,4-dihydro-3,3-dimethyl-1H-2,3-benzooxasilyl(b enzoxasilin)-1-one, 2,2-dimethyl-1-oxa-2-silacyclopentane-5-one, 2,2,3-trimethyl-1-oxa-2-silacyclopentene-5-one, 2,2-dimethyl-4-phenyl-1-oxa-2-silacyclopentane-5-one, 2,2,4-(tert-butyl)-1-oxa-2-silacyclopentane-5-one, 2-methyl-2-(2-propen-1-yl)-1-oxa-2-silacyclopentane-5-one, 1,1-dimethyl-2,1-benzoxasilol-3(1H)-one, 2,2-dimethyl-1-oxa-2-silacycloheptane-7-one. Preferably, the silane lactone of formula (III) is 2,2-dimethyl-1-oxa-4-thia-2-silacyclohexane-6-one. The structure of 2,2-dimethyl-1-oxa-4-thia-2-silacyclohexane-6-one is shown below.

[0117]

[0118] The silane-containing carboxyl groups may be bonded to the SSBR copolymer via one or more divalent structural units of formula (V):

[0119]

[0120] in

[0121] n is an integer from 3 to 6;

[0122] R 5 , R 6 are the same or different and are each independently hydrogen, alkyl, cycloalkyl, aryl, alkaryl, or aralkyl;

[0123] It may contain one or more heteroatoms, and preferably the heteroatoms are one or more selected from the group consisting of O, N, S and Si.

[0124] When a divalent structural unit is present, the SSBR copolymer is bonded to the silicon end of the divalent structural unit according to the following formula:

[0125]

[0126] When a divalent structural unit is present, the silane-containing carboxyl group of formula (I) or (II) is bonded to the oxygen terminal of the divalent structural unit of formula (V).

[0127] The divalent structural unit of formula (V) may be derived from a cyclosiloxane, such as a cyclosiloxane of formula (IV):

[0128]

[0129] in

[0130] n is as defined in formula (V) above;

[0131] R 5 , R 6 As defined above in formula (V).

[0132] R 5 and R 6 can be independently hydrogen, C 1 ~C 12 Straight or branched alkyl, C 3 ~C 12 Cycloalkyl, C 6 ~C 12 Aryl, C 7 ~C 14 Arylalkyl, or C 7 ~C 14Preferably, R 5 and R 6 Can be independently C 1 ~C 6 Straight or branched alkyl, preferably C 1 ~C 3 Straight chain alkyl, more preferably methyl.

[0133] The divalent structural unit of formula (V) may be derived from one or more selected from the group consisting of hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane and dodecamethylcyclohexasiloxane. Preferably, the divalent structural unit is derived from hexamethylcyclotrisiloxane.

[0134] It is particularly advantageous if the end-functionalized SSBR copolymer is terminated with silane-containing carboxyl groups derived from 2,2-dimethyl-1-oxa-4-thia-2-silacyclohexane-6-one, which are bonded to the polymer via divalent structural units derived from hexamethylcyclotrisiloxane.

[0135] The styrene content of the end-functionalized SSBR copolymer can be 10% to 30% by weight, preferably 15% to 25% by weight, more preferably 20% to 22% by weight, such as 20%, 21%, or 22% by weight of the end-functionalized SSBR copolymer. The vinyl content of the end-functionalized SSBR copolymer can be 50% to 75% by weight, preferably 50% to 65%, more preferably 60% to 65%, such as 60%, 61%, 62%, 63%, 64%, or 65% by weight of the end-functionalized SSBR copolymer.

[0136] The average molar mass (number average, Mn) of the end-functionalized SSBR copolymer may be 10,000 to 2,000,000 g / mol, preferably 100,000 to 1,000,000 g / mol.

[0137] The glass transition temperature of the end-functionalized SSBR copolymer may be from -110°C to +20°C, preferably from -60°C to 0°C, preferably from -40°C to -10°C, preferably from -30°C to -15°C, more preferably from -22°C to -26°C, for example -22°C, -23°C, -24°C, -25°C, or -26°C.

[0138] The Mooney viscosity [ML1+4 (100°C)] of the end functionalized SSBR copolymer can be 10 to 200 Mooney units, for example 30 to 150 Mooney units, 40 to 90 Mooney units, 50 to 60 Mooney units, for example 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60 Mooney units.

[0139] The end-functionalized SSBR copolymer can be filled with a filler oil so that the filled end-functionalized SSBR copolymer includes 1% to 10% filler oil, preferably 2.5% to 7.5%, and more preferably 5% filler oil. The filler oil can be one or more selected from the group consisting of DAE (distillate aromatic extract), Tdae (treated distillate aromatic extract), MES (mild extraction solvate), RAE (residual aromatic extract), Trae (treated residual aromatic extract), naphthenic oil, heavy naphthenic oil, paraffin oil, vegetable oil such as coconut oil, synthetic oil such as alkylbenzene oil and castor oil. Preferably, the end-functionalized SSBR copolymer is filled with an aromatic oil such as treated distillate aromatic extract oil (Tdae) so that the filled end-functionalized SSBR copolymer includes 5% treated distillate aromatic extract oil.

[0140] The synthesis of SSBR copolymers terminated with carboxyl groups and compounds of formulae (I) to (V) above is discussed in detail in, for example, International Patent Application No. WO 2014 / 173706 A1.

[0141] Functionalized Silica

[0142] Functionalized silica is silica functionalized with one or more carboxyl groups, the functionalized silica having:

[0143] -BET surface area is between 250 and 310 m 2 / g between;

[0144] -CTAB specific surface area is between 230 and 285 m 2 / g

[0145] - a carbon content of at least 0.10% by weight of the functionalized silica;

[0146] - an object size distribution width ratio Ld of at least 0.91; and,

[0147] - The pore volume distribution ratio is at least 0.65.

[0148] The synthesis of functionalized silica is discussed in detail in International Patent Application No. WO 2015 / 121333 A1. However, in general, the preparation of functionalized silica is carried out by a precipitation reaction of a silicate, such as an alkali metal silicate (e.g. sodium silicate) with an acidifying agent (e.g. sulfuric acid), followed by separation by filtration, resulting in a filter cake of the precipitated silica obtained, followed by liquefaction of the filter cake and finally drying (usually by atomization). The silica can be precipitated in any manner: in particular, the acidifying agent is added to the silicate feedstock, or the acidifying agent and the silicate are added in whole or in part simultaneously to water or the silicate feedstock. During the liquefaction operation, or after the liquefaction operation and before the drying step, one or more polycarboxylic acids are added to the filter cake.

[0149] Functionalized silica may include silica functionalized with one or more carboxyl groups on its surface. The carboxyl group may be present in the form of a carboxylic acid and / or a carboxylate. The carboxyl group may include a polycarboxylic acid comprising two, three, four, or more than four carboxylic acid functional groups. The polycarboxylic acid may be a dicarboxylic acid or a tricarboxylic acid. The polycarboxylic acid may be a straight or branched, saturated or unsaturated aliphatic polycarboxylic acid or an aromatic polycarboxylic acid comprising 2 to 20 carbon atoms. The polycarboxylic acid may include hydroxyl and / or halogen atoms. The aliphatic polycarboxylic acid may contain heteroatoms, such as N or S, on the main chain. The polycarboxylic acid may be one or more selected from the group consisting of a straight, branched, saturated, unsaturated aliphatic polycarboxylic acid and an aromatic polycarboxylic acid comprising 2 to 16 carbon atoms.

[0150] Aliphatic polycarboxylic acids can be made from straight chain, saturated or unsaturated polycarboxylic acids containing 2 to 14 carbon atoms, for example 2 to 12 carbon atoms. Polycarboxylic acids can contain 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 or 12 carbon atoms. Advantageously, polycarboxylic acids can contain 4, 5, 6, 7, 8, 9 or 10 carbon atoms, for example 4, 5, 6, 7 or 8 carbon atoms. Polycarboxylic acids can contain 4, 5 or 6 carbon atoms.

[0151] The polycarboxylic acid may be one or more selected from the group consisting of oxalic acid, malonic acid, tricarboxylic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, methylsuccinic acid, ethylsuccinic acid, methyladipic acid, methylglutaric acid, dimethylglutaric acid, malic acid, citric acid, isocitric acid, and tartaric acid. Preferably, the polycarboxylic acid is one or more selected from the group consisting of adipic acid, succinic acid, ethylsuccinic acid, glutaric acid, methylglutaric acid, oxalic acid, and citric acid.

[0152] The Brunauer-Emmett-Teller (BET) specific surface area of ​​functionalized silica is 250-310 m2 / g. The Brunauer-Emmett-Teller (BET) specific surface area is preferably 270 to 300 m 2 / g, more preferably 280 to 290 m 2 / g, such as 280, 281, 282, 283, 284, 285, 286, 287, 288, 289, or 290m 2 / g.

[0153] The surface area of ​​the functionalized silica by adsorption of cetyltrimethylammonium bromide (CTAB) is 230 m 2 / g~285m 2 / g. The surface area adsorbed by cetyltrimethylammonium bromide (CTAB) may preferably be 240 m 2 / g~270m 2 / g, more preferably 245m 2 / g~265m 2 / g, more preferably 250m 2 / g~260m 2 / g, for example, 250, 251, 252, 253, 254, 255, 256, 257, 258, 259, or 260m 2 / g.

[0154] The pH of the functionalized silica may be 2.5 to 7, preferably 2.5 to 5, more preferably 3 to 4.5, for example, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, 4.1, 4.2, 4.3, 4.4, or 4.5.

[0155] The carbon content of the functionalized silica is at least 0.10% by weight of the functionalized silica. The carbon content (denoted as (C)) is the carbon content of the carboxylic acid plus the corresponding carboxylate, expressed as total carbon. The carbon content may preferably be at least 0.15% by weight of the functionalized silica, more preferably at least 0.20% by weight, more preferably at least 0.25% by weight, more preferably at least 0.30% by weight.

[0156] The object size distribution width ratio Ld of the functionalized silica is at least 0.91. The object size distribution width ratio Ld is preferably at least 0.94. As used herein, the object size distribution width ratio is the object size distribution width ratio (Ld) measured by X-ray disc centrifuge (XDC) particle size analysis after ultrasonic depolymerization (in water), and corresponds to the ratio (d84-d16) / d50, where dn is the size at which n% of the particles (by mass) are smaller than this size (the distribution width Ld is therefore calculated as a whole on the cumulative particle size curve). After ultrasonic depolymerization (in water), the size distribution width Ld of objects smaller than 500 nm measured by XDC particle size analysis corresponds to the ratio (d84-d16) / d50, where dn is the size at which n% of the particles (by mass) are smaller than this size relative to particles smaller than 500 nm (the distribution width Ld is therefore calculated on the cumulative particle size curve, cut off above 500 nm). The object size distribution width as used herein is measured according to the method described in WO 2015 / 121333 A1.

[0157] The pore volume distribution ratio of functionalized silica is at least 0.65. The pore volume distribution is preferably at least 0.66, more preferably at least 0.68. The pore volume and pore size are measured by mercury intrusion (Hg) method using Micromeritics Autopore 9520 porosimeter and calculated by Washburn relationship, wherein the contact angle θ is equal to 140° and the gamma surface tension is equal to 484 dynes / cm (standard DIN 66133). The preparation of each sample is carried out as follows: each sample is pre-dried in an oven at 200°C for 2 hours. As used herein, the pore volume distribution ratio is a pore volume distribution such that the ratio V(d5–d50) / V(d5–d100) is at least 0.65, preferably at least 0.66, more preferably at least 0.68. V(d5–d50) represents the pore volume consisting of pores with diameters between d5 and d50, and V(d5–d100) represents the pore volume consisting of pores with diameters between d5 and d100, dn being the pore diameter (total pore surface area (S)) of the pores with diameters greater than d5. 0 ) can be determined from a mercury intrusion curve). The pore volume distribution ratio as used herein is measured according to the method described in WO 2015 / 121333 A1.

[0158] The amounts of the end-group functionalized SSBR copolymer and the functionalized silica in the rubber composition, as well as the amounts of these two components relative to each other, can have a favorable effect on the properties of the rubber composition of the present invention and the tires made therefrom.

[0159] The amount of the end-functionalized SSBR copolymer may be 10.5 to 100 parts by weight relative to 100 parts by weight of the rubber component, preferably 40 to 90 parts by weight, preferably 50 to 80 parts by weight, more preferably 55 to 75 parts by weight, such as 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75 parts by weight relative to 100 parts by weight of the rubber component. In a specific example, the amount of the end-functionalized SSBR copolymer may be 60 parts by weight or 70 parts by weight relative to 100 parts by weight of the rubber component.

[0160] The amount of functionalized silica can be 20 to 200 parts by weight, preferably 50 to 100 parts by weight, preferably 65 to 85 parts by weight, more preferably 70 to 75 parts by weight, for example, 70, 71, 72, 73, 74, 75 parts by weight, relative to 100 parts by weight of the rubber component. In a specific example, the amount of functionalized silica can be 72 parts by weight relative to 100 parts by weight of the rubber component.

[0161] As described above, the amounts of the end-functionalized SSBR copolymer and the functionalized silica relative to each other in the rubber composition can have a favorable effect on the properties of the rubber composition and the tire made therefrom. The ratio of the amount of functionalized silica to the amount of the end-functionalized SSBR copolymer in parts by weight relative to 100 parts by weight of the rubber component can be 0.5:1 to 2:1, preferably 0.75:1 to 1.50:1, preferably 0.9:1 to 1.40:1, more preferably 0.95:1 to 1.30:1, for example 0.95, 0.96, 0.97, 0.98, 0.99, 1.00, 1.01, 1.02, 1.03, 1.04, 1.06, 1.07, 1.08, 1.09, 1.10, 1.11, 1.12, 1.13, 1.14, 1.15, 1.16, 1.17, 1.18, 1.19, 1.20, 1.21, 1.23, 1.24, 1.25, 1.26, 1.27, 1.28, 1.29, 1.30, 1.31, 1.32, 1.33, 1.34, 1.36, 1.37, 1.38, 1.39, 1.40, 1.41, 1.42, 1.43, 1.44, 1.45, 1.46, 1.47, 1.48, 1.49, 1.50, 1.51, 1.52, 1.53, 1.54, 1.56, 1.57, 1. .02, 1.03, 1.04, 1.05, 1.06, 1.07, 1.08, 1.09, 1.10, 1.11, 1.12, 1.13, 1.14, 1.15, 1.16, 1.17, 1.18, 1.19, 1.20, 1.21, 1.22, 1.23, 1.24, 1.25, 1.26, 1.27, 1.28, 1.29, or 1.30: 1. Tires made from rubber compositions having these relative amounts of functionalized silica and end-functionalized SSBR copolymers have excellent wet performance, rolling resistance, wear resistance, and toughness, as well as an improved balance between these properties, compared to compositions in which either or both of the end-functionalized SSBR copolymer and the functionalized silica are not present.

[0162] When the amount of functionalized silica in parts by weight relative to 100 parts by weight of the rubber component is greater than the amount of the end-functionalized SSBR copolymer in parts by weight relative to 100 parts by weight of the rubber component, the tire made from the rubber composition exhibits particularly improved wear resistance and excellent rolling resistance, wet road performance and toughness and an excellent balance between these properties when compared to tires made from compositions in which the relative amounts of these components are different or compared to compositions in which either or both of the end-functionalized SSBR copolymer and the functionalized silica are absent. In other words, when the ratio of the amount of functionalized silica in parts by weight relative to 100 parts by weight of the rubber component to the amount of the end-functionalized SSBR copolymer is greater than 1:1, preferably, 1.01:1 to 1.50:1, 1.01:1 to 1.40:1, or 1.01:1 to 1.30:1, for example, 1.01, 1.02, 1.03, 1.04, 1.05, 1.06, 1.07, 1.08, 1.09, 1.10, 1.11, 1.12, 1.13, 1.14, 1.15, 1.16, 1.17, 1.18, 1.19, 1.20, 1.21, 1.22, 1.23, 1.24, 1.25, 1.26, 1.27, 1.28, 1.29, 1.30, 1.31, 1.32, 1.33, 1.34, 1.35, 1.36, 1.37, 1.38, 1.39, 1.40, 1.41, 1.42, 1.43, 1.44, 1.45, 1 1.28, 1.29, or 1.30:1.

[0163] According to another aspect, the present invention provides a rubber composition comprising: 58 to 73 parts by weight of a functionalized polymer relative to 100 parts by weight of a rubber component, wherein the functionalized polymer is a polymer functionalized with one or more carboxyl groups; and,

[0164] 70 to 75 parts by weight of functionalized silica relative to 100 parts by weight of the rubber component, wherein the functionalized silica is silica functionalized with one or more carboxyl groups, and the functionalized silica has:

[0165] -BET specific surface area is 250~310m 2 / g;

[0166] -CTAB specific surface area is 230~285m 2 / g

[0167] - a carbon content of at least 0.10% by weight of the functionalized silica;

[0168] - an object size distribution width ratio (Ld) of at least 0.91; and,

[0169] - a pore volume distribution ratio of at least 0.65;

[0170] wherein the ratio of the amount of the functionalized silica to the amount of the functionalized polymer in parts by weight relative to 100 parts by weight of the rubber component is from 1.01:1 to 1.30:1; and,

[0171] The pH of the functionalized silica is 3.5-4.5.

[0172] It has also been found that higher amounts of functionalized silica can particularly improve the wear resistance of tires made from the rubber composition of the present invention. For example, tires made from a rubber composition comprising more than 75 parts by weight, for example, 75 to 200 parts by weight, 75 to 150 parts by weight, 75 to 100 parts by weight, or 75 to 85 parts by weight, for example 80 parts by weight of functionalized silica relative to 100 parts by weight of the rubber component have excellent wear resistance. In particular, including higher amounts of functionalized silica as described above in a rubber composition in which the amount of functionalized silica is greater than the amount of the end-functionalized SSBR copolymer as described above results in excellent wear resistance.

[0173] The present invention further provides a rubber composition comprising:

[0174] 68 to 72 parts by weight of an end-functionalized solution-polymerized styrene-butadiene (SSBR) copolymer, relative to 100 parts by weight of the rubber component, wherein the end groups include one or more carboxyl groups; and,

[0175] Relative to 100 parts by weight of the rubber component, 77.5 to 82.5 parts by weight of functionalized silica, wherein the functionalized silica is silica functionalized with one or more carboxyl groups, and the functionalized silica has:

[0176] -BET specific surface area is 250~310m 2 / g;

[0177] -CTAB specific surface area is 230~285m 2 / g

[0178] - a carbon content of at least 0.10% by weight of the functionalized silica;

[0179] - an object size distribution width ratio (Ld) of at least 0.91; and,

[0180] - a pore volume distribution ratio of at least 0.65;

[0181] wherein the ratio of the amount of the functionalized silica to the amount of the terminal functionalized SSBR copolymer in parts by weight relative to 100 parts by weight of the rubber component is from 1.01:1 to 1.15:1; and,

[0182] The pH of the functionalized silica is 3 to 4.5.

[0183] Other components

[0184] Except end-group functionalized SSBR copolymer and functionalized silica, rubber composition of the present invention can also include other components.These other components can include one or more selected from the group consisting of other polymer (different from the end-group functionalized SSBR copolymer discussed above), vulcanizing agent, vulcanization accelerator, vulcanization accelerating aid, filler, silane coupling agent, antidegradant such as antioxidant or antiozonant, wax and oil.For example, composition of the present invention can further include other polymer, vulcanizing agent, vulcanization accelerator, vulcanization accelerating aid, carbon black, silane coupling agent, antidegradant, wax and oil.

[0185] The additional polymer of the rubber composition is not particularly limited (except that it is different from the end-functionalized SSBR copolymer discussed above), and can be any of those known to those skilled in the art. The additional polymer can include a diene polymer and / or a diene copolymer obtainable by copolymerization of a diene monomer with a vinyl aromatic monomer. For example, the additional polymer can include one or more selected from the group consisting of polybutadiene, polyisoprene, butadiene-isoprene copolymer, styrene-butadiene copolymer, isoprene-styrene copolymer, or butadiene-isoprene-styrene terpolymer. Preferably, the additional polymer is a solution-polymerized styrene-butadiene copolymer, such as Arlanxeo's VSL 3038-2HM. The further polymer may be oil filled. The filler oil may be one or more selected from the group consisting of DAE (Distillate Aromatic Extract), Tdae (Treated Distillate Aromatic Extract), MES (Mild Extraction Solvate), RAE (Residual Aromatic Extract), Trae (Treated Residual Aromatic Extract), naphthenic oil, heavy naphthenic oil, paraffinic oil, vegetable oil such as coconut oil, synthetic oil such as alkylbenzene oil and castor oil. Preferably, the filler oil is an aromatic oil such as Tdae (Treated Distillate Aromatic Extract). The amount of oil present in the further polymer may vary between 20% and 40% of the total amount of the further polymer of the filler oil, for example 27.3%. The amount of the additional polymer is not particularly limited, but can be 0 to 89.5 parts by weight, preferably 10 to 60 parts by weight, preferably 20 to 50 parts by weight, more preferably 25 to 45 parts by weight, for example, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44 or 45 parts by weight relative to 100 parts by weight of the rubber component.

[0186] The vulcanizing agent of the rubber composition of the present invention is not particularly limited, and may be any of those known to those skilled in the art. For example, the vulcanizing agent may be sulfur. The amount of the vulcanizing agent included in the rubber composition of the present invention is not particularly limited, but may be 0.1 to 5 parts by weight relative to 100 parts by weight of the rubber component. For example, the rubber composition may include 0.1 to 2 parts by weight, preferably 0.1 to 1 part by weight, more preferably 0.5 to 1 part by weight, for example, 0.5, 0.6, 0.7, 0.8, 0.9 or 1 part by weight relative to 100 parts by weight of the rubber component.

[0187] The vulcanization accelerator of the rubber composition of the present invention is not particularly limited, and can be any one of those known to those skilled in the art. For example, the vulcanization accelerator can be one or more selected from the group consisting of: thiazole type vulcanization accelerator, such as 2-mercaptobenzothiazole (MBT), dibenzothiazole disulfide (MBTS), N-cyclohexyl-2-benzothiazole sulfenamide (CBS) and N-tert-butyl-2-benzothiazole sulfenamide (TBBS); guanidine type vulcanization accelerator such as 1,3-diphenylguanidine (DPG); thiuram-based vulcanization accelerator, such as tetramethylthiuram disulfide, tetrabutylthiuram disulfide, tetra(dodecyl)thiuram disulfide, tetraoctylthiuram disulfide and tetrabenzylthiuram disulfide; and dithiocarbamate compounds such as zinc dimethyldithiocarbamate; and other zinc dialkyldithiophosphates. Preferably, the vulcanization accelerator may be a combination of dibenzothiazyl disulfide (MBTS), N-cyclohexyl-2-benzothiazole sulfenamide (CBS) and 1,3-diphenylguanidine (DPG). The total amount of the vulcanization accelerator is not particularly limited, but may be 0.2 to 10 parts by weight, preferably 0.5 to 8 parts by weight, preferably 1 to 5 parts by weight, more preferably 2 to 4 parts by weight, for example, 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9 or 4 parts by weight relative to 100 parts by weight of the rubber component. The amount of each vulcanization accelerator may be 0.1 to 5 parts by weight, preferably 0.5 to 3 parts by weight, more preferably 0.75 to 2 parts by weight, for example, 0.8, 0.9, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, or 2 parts by weight relative to 100 parts by weight of the rubber component. Preferably, the vulcanization accelerator of the rubber composition of the present invention may include 1 to 2 parts by weight of dibenzothiazyl disulfide (MBTS), 0.75 parts by weight of N-cyclohexyl-2-benzothiazole sulfenamide (CBS), and 1.3 parts by weight of 1,3-diphenylguanidine (DPG) relative to 100 parts by weight of the rubber component.

[0188] The vulcanization accelerator of the present invention is not particularly limited, and can be any one of those known to those skilled in the art. For example, the vulcanization accelerator can be zinc oxide (ZnO) and fatty acids. The fatty acid can be saturated or unsaturated, or any one of straight or branched fatty acids. The number of carbon atoms of the fatty acid is also not particularly limited, but can be 1 to 30 or 15 to 30. For example, the fatty acid can be selected from one or more of the following groups: cyclohexane acid (cyclohexane carboxylic acid), cycloalkane acids with side chains such as alkylcyclopentane, saturated fatty acids such as caproic acid, octanoic acid, decanoic acid (including branched carboxylic acids such as neodecanoic acid), dodecanoic acid, tetradecanoic acid, hexadecanoic acid and octadecanoic acid (stearic acid), unsaturated fatty acids such as methacrylic acid, oleic acid, linoleic acid and linolenic acid, and resin acids such as rosin, tall oil acid and abietic acid. Preferably, the vulcanization accelerator of the present invention is zinc oxide (ZnO) and stearic acid. The amount of the vulcanization accelerator is not particularly limited, but can be 1 to 10 parts by weight, such as 1.5 to 7 parts by weight, or 2 to 5 parts by weight, such as 2, 2.5, 3, 3.5, 4, 4.5, or 5 parts, relative to 100 parts by weight of the rubber component. Preferably, zinc oxide (ZnO) is present in an amount of 2 parts by weight and stearic acid is present in an amount of 1.5 parts by weight relative to 100 parts by weight of the rubber component.

[0189] The carbon black of the rubber composition of the present invention is not particularly limited and may be any of those known to those skilled in the art. The carbon black may be furnace black, channel black and lamp black. For example, the carbon black may be one or more selected from the group consisting of super wear resistant furnace black (SAF), high wear resistant furnace black (HAF), fast extrusion furnace black (FEF), fine furnace black (FF), medium super wear resistant furnace black (ISAF), semi-reinforced furnace black (SRF), medium processing channel black, difficult processing channel black and conductive channel black. Other carbon blacks that can be used include acetylene black. The carbon black may be a granulated form or an ungranulated flocculent substance. A specific example of the carbon black in the rubber composition of the present invention is Orion Engineered Carbons' N234. The amount of carbon black included in the rubber composition of the present invention is not particularly limited, but may be 0.1 to 10 parts by weight, such as 0.5 to 5 parts by weight or 1 to 4 parts by weight, such as 1, 2, 3, or 4 parts by weight, relative to 100 parts by weight of the rubber component. Preferably, the carbon black is present in 2 to 3 parts by weight relative to 100 parts by weight of the rubber component.

[0190] Advantageously, the only silica-based filler included in the rubber composition of the present invention is the functionalized silica discussed above. In other words, no additional silica may be present. However, the present invention does not necessarily exclude the presence of additional silica-based fillers. Additional silica-based fillers may include any of those known to those skilled in the art (excluding the functionalized silica discussed above), including precipitated amorphous silica, wet silica (hydrated silicic acid), dry silica (anhydrous silicic acid), fumed silica, calcium silicate, aluminum silicate, magnesium silicate (e.g., Mg 2 SiO 4 MgSiO 3 ), calcium magnesium silicate (CaMgSiO 4 ), calcium aluminum silicate (e.g., Al 2 O 3 .CaO 2 SiO 2 ).

[0191] The rubber composition may include additional fillers known to those skilled in the art. For example, the rubber composition of the present invention may include one or more selected from the group consisting of aluminum hydroxide, talc, aluminum oxide (Al 2 O 3 ), aluminum hydroxide (Al 2 O 3 H 2 O), aluminum hydroxide (Al(OH) 3 ), aluminum carbonate (Al 2 (CO 3 ) 2 ), magnesium alumina (MgOAl 2 O 3 ), pyrofilite (Al 2 O 3 .4SiO 2 .H 2 O), bentonite (Al 2 O 3 .4SiO 2 .2H 2 O), mica, kaolin, glass balls, glass beads, calcium oxide (CaO), calcium hydroxide (Ca(OH) 2 ), calcium carbonate (CaCO 3 ), magnesium carbonate, magnesium hydroxide (Mg(OH) 2 ), magnesium oxide (MgO), magnesium carbonate (MgCO 3 ), potassium titanate, barium sulfate, zirconium oxide (ZrO 2 ), zirconium hydroxide [Zr(OH) 2 .nH 2O], zirconium carbonate [Zr(CO 3 ) 2 ], crystalline aluminosilicate, reinforcing grade zinc oxide (i.e., reinforcing zinc oxide). The amount of other fillers can be 5 to 200 parts by weight relative to 100 parts by weight of the rubber component, for example, 10 to 150 parts by weight, or 25 to 100 parts by weight relative to 100 parts by weight of the rubber component.

[0192] The silane coupling agent of the rubber composition of the present invention is not particularly limited and may be any one of those known to those skilled in the art. For example, the silane coupling agent of the present invention may be one or more selected from the group consisting of bis(3-triethoxysilylpropyl)tetrasulfide, bis(3-triethoxysilylpropyl)trisulfide, bis(3-triethoxysilylpropyl)disulfide, bis(2-triethoxysilylethyl)tetrasulfide, bis(3-trimethoxysilylpropyl)tetrasulfide, bis(2-trimethoxysilylethyl)tetrasulfide, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 2-mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane, 3-trimethoxysilylpropyl-N,N-dimethylthiocarbamoyltetrasulfide, 3-triethoxy Preferably, the silane coupling agent is bis(3-triethoxysilylpropyl)tetrasulfide. A specific example of a silane coupling agent is Si from Evonik Industries AG. The amount of the silane coupling agent is not particularly limited, but can be 2 to 20 parts by weight, preferably 5 to 15 parts by weight, preferably 7 to 13 parts by weight, more preferably 9 to 12 parts by weight, relative to 100 parts by weight of the rubber component, for example, 9, 9.1, 9.2, 10.3, 9.4, 9.5, 9.6, 9.7, 9.8, 9.9, 10, 10.1, 10.2, 10.3, 10.4, 10.5, 10.6, 10.7, 10.8, 10.9, 11, 11.1, 11.2, 11.3, 11.4, 11.5, 11.6, 11.7, 11.8, 11.9, or 12 parts by weight relative to 100 parts by weight of the rubber component.

[0193] The oil of the rubber composition of the present invention is not particularly limited, and can be any one of those known to those skilled in the art.For example, the oil of the present invention can be selected from processing oils such as aromatic oils, such as DAE (distillate aromatic extract)-, Tdae (treated distillate aromatic extract)-, MES (gentle extraction solvate)-, RAE (residual aromatic extract)-, Trae (treated residual aromatic extract)-, naphthenic oil and heavy naphthenic oil, paraffin oil, vegetable oil such as coconut oil, synthetic oil such as alkylbenzene oil and castor oil composition group one or more.Preferably, oil is aromatic oil, such as residual aromatic extraction oil.The oil of rubber composition can be added to rubber composition in the form of a polymer filler present in more than one polymer (for example, functionalized or non-functionalized SSBR copolymer).

[0194] The total amount of oil in the rubber composition is calculated by the sum of the filler oil present in the one or more polymers and any additional oil components that may be present. The total amount of oil is not particularly limited, but can be 5 to 60 parts by weight, preferably 8 to 50 parts by weight, preferably 10 to 45 parts by weight, more preferably 15 to 40 parts by weight, for example, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29 or 30 parts by weight relative to 100 parts by weight of the rubber component.

[0195] The antidegradant of the rubber composition of the present invention is not particularly limited and may be any of those known to those skilled in the art. The antidegradant may be an antioxidant and / or an antiozonant. For example, the antidegradant may be one or more selected from the group consisting of N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD) and 2,2,4-trimethyl-1,2-dihydroquinoline polymer (TMQ). Preferably, the antidegradant is a combination of N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD) and 2,2,4-trimethyl-1,2-dihydroquinoline polymer (TMQ). Relative to 100 parts by weight of the rubber component, the amount of each antidegradant may be 0.1 to 3 parts by weight, for example, 0.5 to 1.5 parts by weight, for example, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0 parts by weight relative to 100 parts by weight of the rubber component. The total amount of the antidegradant can be 0.1 to 10 parts by weight, preferably 0.1 to 5 parts by weight, preferably 0.5 to 3 parts by weight, more preferably 1 to 2 parts by weight, relative to 100 parts by weight of the rubber component, for example, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, or 2 parts by weight, relative to 100 parts by weight of the rubber component.

[0196] According to another aspect, the present invention provides a method for making a rubber compound by compounding the rubber composition of the present invention.

[0197] According to another aspect, the present invention provides a method for manufacturing a rubber product, comprising the steps of: compounding the rubber composition of the present invention to form a rubber compound; molding the rubber compound into a desired shape; and vulcanizing the rubber compound.

[0198] Rubber composition manufacturing and compounding

[0199] When preparing rubber composition of the present invention, the combination method of each component is not limited, and any one of the methods known to those skilled in the art can be used. For example, all component materials can be blended and mixed at one time, or they can be blended and mixed in multiple steps. For blending and mixing, a mixing machine such as a roller mixer, an internal mixer or a Banbury internal mixer can be used. In order to shape the rubber composition into a sheet or strip shape, any known molding machine, such as an extrusion molding machine or a compression molding machine can be used.

[0200] vulcanization

[0201] The vulcanization conditions for hardening the rubber composition are not limited and may be any of those known to those skilled in the art. However, a vulcanization condition of treating at 140 to 180° C. for 5 to 120 minutes is generally adopted.

[0202] Tire Manufacturing

[0203] The tire of the present invention is not specifically limited except that it is prepared using the rubber composition of the present invention and can be appropriately selected according to the intended purpose. Because the tire is made using the rubber composition of the present invention, it has excellent wear resistance, rolling resistance, wet road performance and toughness and an excellent balance between these properties.

[0204] The components of the tire in which the rubber composition of the present invention is used are not specifically limited and can be appropriately selected according to the intended purpose. For example, the rubber composition can be used in the tread, the base tread, the sidewall, the sidewall reinforcing rubber, the bead filler, etc. Among these, the rubber composition is advantageously used in the tread component.

[0205] Regarding the manufacturing method of the tire, any method known to those skilled in the art can be used. For example, components commonly used in tire manufacturing, such as a carcass layer, a belt layer, and a tread layer formed by at least one selected from the group consisting of an unvulcanized rubber composition and a cord, are sequentially stacked on a drum to form a tire, and then the drum is removed to obtain a green tire. Next, the green tire is vulcanized under heating according to a common method to manufacture a desired tire. The tire can be, for example, a pneumatic tire.

[0206] Example

[0207] The invention will now be illustrated by the following examples, which are intended to illustrate the invention without limiting its scope in any way.

[0208] Test methods

[0209] Brunauer-Emmett-Teller (BET) specific surface area—the specific surface area of ​​functionalized silica is measured by the BET method according to the method described in Journal of the American Chemical Society, Vol. 60, p. 309, February 1938, and corresponds to standard NF ISO 5794-1, Annex D (June 2010).

[0210] Cetyltrimethylammonium bromide (CTAB) adsorption method – The surface area of ​​functionalized silica was measured by the CTAB method according to ASTM D6845.

[0211] Carbon content of carboxylic acids plus corresponding carboxylates (C) - The content of carboxylic acids plus corresponding carboxylates, expressed as total carbon, expressed as (C), can be measured using a carbon / sulfur analyzer such as the Horiba EMIA 320V2 machine. The principle of a carbon / sulfur analyzer is based on the combustion of a solid sample in a stream of oxygen in an induction furnace (regulated to about 170 mA) and in the presence of a combustion accelerator (about 2 g of tungsten (in particular Lecocel 763-266) and about 1 g of iron). The analysis lasts about 1 minute. The carbon present in the sample to be analyzed (mass of about 0.2 g) combines with oxygen to form CO 2 and CO. The decomposition gases are then analyzed by an infrared detector. The moisture in the sample and the water produced during the oxidation reactions are removed by passing through a cartridge containing a dehydrating agent (magnesium perchlorate) so as not to interfere with the infrared measurements. The results are expressed as a mass percentage of elemental carbon.

[0212] Object size distribution width ratio Ld—The object size distribution width ratio is the object size distribution width ratio Ld ((d84−d16) / d50) measured by XDC particle size analysis after ultrasonic deagglomeration according to the method described in WO 2015 / 121333 A1.

[0213] Pore ​​volume distribution - The pore volume distribution is the pore volume distribution ratio V(d5-d50) / V(d5-d100) measured according to the method described in WO 2015 / 121333 A1.

[0214] Functionalized Silica pH - The pH of functionalized silica was measured according to the method described in WO 2015 / 121333 A1 derived from ISO 787 / 9.

[0215] Mooney Viscosity - Mooney viscosity is measured according to ASTM D1646 on pristine functionalized or non-functionalized polymers.

[0216] Rolling Resistance (RR) – Rolling resistance is measured in accordance with Annex 6 of UN Regulation No. 117, Revision 4, 2016.

[0217] Wet Road Performance – Wet road performance is measured in accordance with Annex 5 of UN Regulation No. 117, Revision 4, 2016.

[0218] Toughness (TB*EB) - Toughness measurement is based on the tensile properties of the compound measured according to International Organization for Standardization (ISO) 5893 at 100°C.

[0219] Payne Effect (%) – The Payne Effect is calculated from the dynamic properties of the compound measured in a stress / strain test at room temperature according to ISO 4664 standard. The Payne Effect can predict the filler dispersion in the rubber composition from the ratio (expressed as a percentage) between ΔE' / E(0.1% strain), where ΔE' is the difference between E'(0.1% strain) – E'(4% strain). The lower the Payne Effect, the better the filler dispersion in the rubber composition. In Table 2 below, the Payne Effect data are presented relative to Comparative Example 1, where the Payne Effect has been normalized to 100. Payne Effect values ​​greater than 100 indicate that filler dispersion is improved compared to Comparative Example 1.

[0220] End-functionalized SSBR copolymer

[0221] In the following examples, end-functionalized SSBR copolymers were prepared according to Example 3 of WO 2014 / 173706 A1 as described below.

[0222] To an inertized 20-liter reactor were added hexane (8.5 kg), 1,3-butadiene (1,185 g), styrene (315 g), 2,2-bis(2-tetrahydrofuryl)propane (8.6 mmol) and butyl lithium (11.3 mmol), and the contents were heated to 60° C. Polymerization was carried out while stirring at 60° C. for 25 minutes. Subsequently, hexamethylcyclotrisiloxane (as a cyclohexane solution) in an amount equimolar to the butyl lithium was added, and the reactor contents were then heated to 60° C. for an additional 20 minutes to cap the anionic ends of the polymer chains. 20 minutes after the addition of the hexamethylcyclotrisiloxane, 2,2-dimethyl-1-oxa-4-thia-2-silacyclohexane-6-one (as a toluene solution) in an amount equimolar to the butyl lithium and the hexamethylcyclotrisiloxane was added, and the mixture was heated to 60° C. for an additional 20 minutes. The rubber solution was discharged and the mixture was heated to 60° C. by adding 1520 (2,4-bis(octylthiomethyl)-6-methylphenol) (3 g) was stabilized and the solvent was removed by stripping with steam. The rubber crumb was dried at 65° C. under reduced pressure.

[0223] Functionalized Silica

[0224] In the following examples, functionalized silica was prepared according to Example 6 in WO 2015 / 121333 A1, wherein for functionalized silica A, the amount of methylglutaric acid (MGA) added was 0.40 wt% (expressed as MGA mixture / SiO 2 The pH was adjusted to 3-3.7, and the amount of MGA added to the functionalized silica B was 0.40 wt% (expressed as MGA mixture / SiO 2 weight ratio), and the pH was adjusted to 3.5-4.2.

[0225] The properties of Functionalized Silica A and Functionalized Silica B are shown in Table 1 below.

[0226] Table 1

[0227] performance Functionalized Silica A Functionalized Silica B <![CDATA[BET surface area (m 2 / g)]]> 286 288 <![CDATA[CTAB surface area (m 2 / g)]]> 253 254 pH 3.7 4.1 Carbon content 0.15 0.15 Object size distribution width ratio (Ld) 1.11 1.36 Pore ​​volume distribution ratio 0.71 0.71

[0228] Rubber composition

[0229] Tables 2 and 3 below show the rubber compositions of Examples 1 to 4 and Comparative Examples 1 to 3. The rubber compositions were prepared by mixing the components listed in Tables 2 and 3. Table 2 shows the polymer and silica components of the rubber composition, while Table 3 shows the other components. The values ​​given in Tables 2 and 3 are in parts by weight relative to 100 parts by weight of the rubber component (PHR). The amounts of polymer components given in Table 2 (i.e., the amounts of non-functionalized SSBR, hydroxyl-functionalized SSBR, and end-functionalized SSBR copolymers) include the percentage amount of filler oil listed in the description of each polymer in column 2 of Table 2. That is, in order to calculate the amount of pure SSBR copolymer present in the composition by weight relative to 100 parts by weight of the rubber component, the values ​​given in Table 2 should be adjusted to take into account the percentage amount of filler oil present. The rubber composition was subjected to the above-mentioned test method.

[0230] Table 2 further shows the viscoelastic properties of tires prepared from rubber composition examples 1 to 4 and comparative examples 1 to 3. The results are presented relative to comparative example 1, wherein all values ​​of viscoelastic properties listed have been normalized to 100. Therefore, if the value of viscoelastic properties is greater than 100, an improvement in the property is indicated, and if the value of viscoelastic properties is less than 100, a decrease in the viscoelastic properties is indicated. When the value of viscoelastic properties is 100, the results are the same as those of comparative example 1.

[0231] The "remainder" figure is the sum of the values ​​of the viscoelasticity of each composition minus 400. Since the values ​​of each of the four viscoelastics of Comparative Example 1 have been set to 100, the margin of Comparative Example 1 is 0. Therefore, a margin greater than 0 indicates an improvement in overall viscoelasticity compared to Comparative Example 1.

[0232] The "Notes" summarize the characteristics of the polymer and silica components of each rubber composition.

[0233] Table 2

[0234]

[0235] Notes on Comparative Examples (CE)

[0236] CE 1: No carboxyl functionalized components

[0237] CE 2: Carboxyl functionalized SSBR, non-functionalized silica

[0238] CE 3: Hydroxyl functionalized SSBR, carboxyl functionalized silica

[0239] Notes on Experimental Examples (EE)

[0240] EE 1: Carboxyl functionalized SSBR, carboxyl functionalized silica

[0241] EE 2: Carboxyl functionalized silica with higher pH (4.2 vs 3.7)

[0242] EE 3: The ratio of functionalized silica to functionalized polymer is less than 1

[0243] EE 4: Higher amounts of functionalized silica

[0244] Table 3

[0245]

[0246] Results and discussion:

[0247] The residual data of Experimental Examples 1 to 4 are significantly higher than the residual data of Comparative Examples 1 to 3, indicating an overall improvement in the viscoelasticity of tires prepared from compositions containing both end-functionalized SSBR and functionalized silica. In addition, an interactive and / or synergistic effect is achieved by combining end-functionalized SSBR and functionalized silica.

[0248] Comparing Comparative Example 3 with Experimental Examples 1-4, improvements in overall viscoelasticity, particularly wear resistance and rolling resistance, were achieved when using end-functionalized SSBR as compared to hydroxyl functionalized polymers.

[0249] Comparison of Experimental Examples 1 and 2 shows that improvements in overall viscoelasticity, particularly wear resistance and rolling resistance, are achieved at a pH of 3.7 compared to a pH of 4.2.

[0250] From the comparison between Experimental Examples 1 and 3, it can be seen that when the amount of functionalized silica is greater than the amount of end-group functionalized SSBR, improvements in overall viscoelasticity, particularly wear resistance and toughness, are achieved.

[0251] It can be seen from Experimental Example 4 that a higher amount of functionalized silica significantly improves the wear resistance.

Claims

1. A rubber composition, include: a rubber component comprising an end-functionalized solution polymerized styrene-butadiene SSBR copolymer, wherein the end-functionalized SSBR copolymer comprises terminal carboxyl groups; and, Functionalized silica, wherein the functionalized silica is silica functionalized with one or more carboxyl groups, the functionalized silica having: -BET specific surface area is 250~310m 2 / g; -CTAB specific surface area is 230~285m 2 / g - a carbon content of at least 0.10% by weight of the functionalized silica; - an object size distribution width ratio Ld of at least 0.91; and, - a pore volume distribution ratio of at least 0.65; The object size distribution width ratio Ld is measured by X-ray disc centrifuge XDC particle size analysis after ultrasonic deagglomeration in water, corresponding to the ratio (d84-d16) / d50, wherein dn is the size at which n% of the particles are smaller than this size by mass, wherein the distribution width ratio Ld is calculated as a whole on the cumulative particle size curve; the pore volume distribution ratio is the pore volume distribution ratio such that the ratio V(d5-d50) / V(d5-d100) is at least 0.65, V(d5-d50) represents the pore volume composed of pores with diameters between d5 and d50, V(d5-d100) represents the pore volume composed of pores with diameters between d5 and d100, dn is the pore diameter of which n% of the total surface area of ​​all pores is provided by pores with diameters greater than this diameter, wherein the total surface area of ​​the pores S 0 Determined by the mercury injection curve.

2. The rubber composition of claim 1, wherein the end-functionalized SSBR copolymer comprises a terminal silane-containing carboxyl group of formula (I): in: R 1 and R 2 are the same or different and are each independently hydrogen, alkyl, alkoxy, cycloalkyl, cycloalkoxy, aryl, aryloxy, alkylaryl, alkylaryloxy, aralkyl, or aralkyloxy, which contain one or more heteroatoms or no heteroatoms, wherein the heteroatoms are one or more selected from the group consisting of O, N, S and Si; R 3 and R 4 are the same or different and are each independently hydrogen, alkyl, cycloalkyl, aryl, alkaryl, or aralkyl, and contain one or more heteroatoms or no heteroatoms, wherein the heteroatoms are one or more selected from the group consisting of O, N, S and Si; and, A is a divalent organic group, which is an alkyl group; selected from O, NR 7 , S and SiR 8 R 9 or an alkyl group containing one or more heteroatoms, wherein the heteroatoms are selected from O, NR 7 , S, and SiR 8 R 9 One or more of the groups consisting of.

3. The rubber composition according to claim 2, wherein the silane-containing carboxyl group is present as a carboxylate of formula (II): in: R 1 and R 2 are the same or different and are each independently hydrogen, alkyl, alkoxy, cycloalkyl, cycloalkoxy, aryl, aryloxy, alkylaryl, alkylaryloxy, aralkyl, or aralkyloxy, which contain one or more heteroatoms or no heteroatoms, wherein the heteroatoms are one or more selected from the group consisting of O, N, S and Si; R 3 and R 4 are the same or different and are each independently hydrogen, alkyl, cycloalkyl, aryl, alkaryl, or aralkyl, and contain one or more heteroatoms or no heteroatoms, wherein the heteroatoms are one or more selected from the group consisting of O, N, S and Si; and, A is a divalent organic group, which is an alkyl group; selected from O, NR 7 , S and SiR 8 R 9 or an alkyl group containing one or more heteroatoms, wherein the heteroatoms are selected from O, NR 7 , S, and SiR 8 R 9 One or more of the group consisting of; and, M is a 1- to 4-valent metal or semimetal, n is an integer of 1 to 4.

4. The rubber composition according to any one of claims 1 to 3, wherein the end-functionalized SSBR copolymer is obtainable by reacting a SSBR copolymer with one or more functionalizing agents in the form of silicone lactones, wherein the silicone lactones are compounds of formula (III): in R 1 and R 2 are the same or different and are each independently hydrogen, alkyl, alkoxy, cycloalkyl, cycloalkoxy, aryl, aryloxy, alkylaryl, alkylaryloxy, aralkyl, or aralkyloxy, which contain one or more heteroatoms or no heteroatoms, wherein the heteroatoms are one or more selected from the group consisting of O, N, S and Si; R 3 and R 4 are the same or different and are each independently hydrogen, alkyl, cycloalkyl, aryl, alkaryl, or aralkyl, and contain one or more heteroatoms or no heteroatoms, wherein the heteroatoms are one or more selected from the group consisting of O, N, S and Si; and, A is a divalent organic group, which is an alkyl group; selected from O, NR 7 , S and SiR 8 R 9 or an alkyl group containing one or more heteroatoms, wherein the heteroatoms are selected from O, NR 7 , S, and SiR 8 R 9 One or more of the groups consisting of.

5. The rubber composition according to claim 2 or 3, wherein the silane-containing carboxyl group is bonded to the SSBR copolymer via one or more divalent structural units of formula (V): The divalent structural unit is derived from a cyclosiloxane of formula (IV): in n is an integer from 3 to 6; R 5 , R 6 are the same or different and are each independently hydrogen, alkyl, cycloalkyl, aryl, alkaryl, or aralkyl; and contain one or more heteroatoms or no heteroatoms, wherein the heteroatom is O, N, S, or Si.

6. The rubber composition according to any one of claims 1 to 3, wherein the functionalized silica is functionalized on its surface with one or more polycarboxylic acids, wherein the one or more polycarboxylic acids are one or more selected from the group consisting of adipic acid, succinic acid, ethylsuccinic acid, glutaric acid, methylglutaric acid, oxalic acid, and citric acid.

7. The rubber composition according to any one of claims 1 to 3, wherein the carbon content of the functionalized silica is at least 0.15 wt%.

8. The rubber composition of any one of claims 1 to 3, wherein the functionalized silica has an object size distribution width ratio of at least 0.

94.

9. The rubber composition according to any one of claims 1 to 3, wherein the pore volume distribution ratio of the functionalized silica is at least 0.

66. 10 . The rubber composition according to claim 1 , wherein the pH of the functionalized silica is 2.5 to 7.

11. The rubber composition according to any one of claims 1 to 3, include: 10.5 to 100 parts by weight of the terminal functionalized SSBR copolymer relative to 100 parts by weight of the rubber component; and, Relative to 100 parts by weight of the rubber component, 20 to 200 parts by weight of the functionalized silica.

12. The rubber composition according to any one of claims 1 to 3, wherein the ratio of the amount of functionalized silica per hundred parts of the rubber component to the amount of the end-functionalized SSBR copolymer per hundred parts of the rubber component is from 0.5:1 to 2:

1.

13. The rubber composition according to any one of claims 1 to 3, wherein the rubber composition is compounded.

14. The rubber composition according to claim 3, wherein the 1-4 valent metal or semimetal is Li, Na, K, Mg, Ca, Zn, Fe, Co, Ni, Al, Nd, Ti, Sn, Si, Zr, V, Mo or W. 15 . The rubber composition according to claim 5 , wherein the divalent structural unit is derived from one or more cyclosiloxanes selected from the group consisting of hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, and dodecamethylcyclohexasiloxane.

16. A rubber article comprising the rubber composition according to any one of the preceding claims, wherein the rubber composition is vulcanized. 17 . A tire comprising the rubber composition according to claim 1 or the rubber product according to claim 16 .

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