Sulfur-crosslinkable rubber composition, sulfur-vulcanized rubber composition, rubber product and tire thereof

Abstract

The present invention relates to a sulfur-crosslinkable rubber composition, a sulfur-vulcanized rubber composition obtainable from the corresponding sulfur-crosslinkable rubber composition, a rubber product comprising said sulfur-vulcanized rubber composition and a tire thereof.

Description

Technical Field

[0001] This invention relates to sulfur-crosslinkable rubber compositions, sulfur-vulcanized rubber compositions obtainable from the corresponding sulfur-crosslinkable rubber compositions, rubber products comprising the sulfur-vulcanized rubber compositions, and tires thereof.

[0002] The subject matter of this invention is defined in the following claims. Background Technology

[0003] Since the beginning of the 21st century, the automotive industry has been one of the industrial sectors facing the most fundamental challenges and experiencing several disruptive technological advancements. Growing consumer awareness of ecological aspects such as emissions profiles and resource efficiency necessitates new concepts of mobility. Simultaneously, there is a growing demand for improved vehicle performance characteristics and increasingly stringent overall safety regulations. Addressing these challenges is not solely the responsibility of vehicle manufacturers. In fact, several aspects are significantly influenced by vehicle tire characteristics, making tire optimization a crucial objective.

[0004] Several relevant properties of pneumatic vehicle tires (such as rolling resistance, hardness, and abrasion resistance) are closely related to the rubber composition of the tread. Therefore, a significant amount of research has focused on optimizing the properties of such compositions. Indeed, considerable progress has been made in recent years, for example, by replacing carbon black fillers with silica. Unfortunately, many different physicochemical properties of vulcanized rubber compositions related to tire performance cannot be changed independently of each other, leading to trade-offs where one property cannot be enhanced without negatively impacting another related property. For example, improvements in wet grip and dry braking often result in deterioration of rolling resistance, winter performance, and wear characteristics. Therefore, the optimization of rubber compositions often aims to resolve these trade-offs by developing solutions that improve specific parameters without significantly hindering the corresponding complementary properties.

[0005] Essential components of sulfur-crosslinkable rubber compositions are rubber polymers. Over time, these polymers have become the subject of extensive research in search of modifications, such as the introduction of functional groups, to specifically improve certain properties. Typically, such modifications can be present to varying degrees. For example, polymer chains with two ends can be either single-end modified or double-end modified. Alternatively or concurrently, the polymer backbone can also be modified. Typically, these modifications and functional groups are designed to specifically interact with the filler material or another component of the composition. For example, some functional groups are designed to specifically interact with silica, while others are specifically designed to interact with carbon black. Depending on the overall rubber composition, such modified polymers can specifically bind to silica, carbon black, or both filler materials in the composition.

[0006] However, the more functional groups present in a polymer, the more likely it is to undergo undesirable side reactions (such as undesirable crosslinking) before mixing or to prematurely bind with filler materials during mixing. This is generally undesirable, especially premature binding during mixing. In particular, bi-end modified polymers often exhibit a tendency to prematurely over-bind with their corresponding filler materials during mixing, making mixing impossible. Although such polymers are theoretically promising for improving physicochemical properties, they are often unusable. Summary of the Invention

[0007] In view of the above background, the object of the present invention is to overcome the aforementioned disadvantages by finding suitable dual-end modified polymers and to provide a sulfur-crosslinkable rubber composition with improved physicochemical properties. More specifically, this object is particularly aimed at further improving and better balancing the rolling and abrasion resistance (wear) of corresponding sulfur-vulcanized rubber compositions, rubber products, and especially tires.

[0008] Furthermore, the object of the present invention is to provide a sulfur-crosslinkable rubber composition that exhibits improved filler material affinity between the polymer used in the sulfur-crosslinkable rubber composition and the filler material.

[0009] The above objective is achieved by the subject matter of this invention, and in particular by a sulfur-crosslinkable rubber composition comprising...

[0010] (a) Packing material components ranging from 1 to 350 phr in total quantity, and

[0011] (b) at least one modified conjugated diene-based polymer having

[0012] One or more polymer chains, each comprising a structural unit derived from a conjugated diene compound, wherein the ends of each polymer chain are modified with functional groups, which are either nitrogen-containing or sulfur-containing functional groups.

[0013] The condition is

[0014] A) - At least one of these ends is modified with a nitrogen-containing functional group and at least another of these ends is modified with a sulfur-containing functional group, and / or (preferably and)

[0015] - In each polymer chain with two corresponding ends, one end is modified with a nitrogen-containing functional group and the other end is modified with a sulfur-containing functional group;

[0016] or

[0017] B) - Two, three, or more than three polymer chains in one polymer chain are linked together by nitrogen-containing or sulfur-containing functional groups that act as linking groups, and

[0018] - The functional group that modifies the ends of the two, three or more polymer chains is (i) a sulfur-containing functional group (if the linking group is a nitrogen-containing functional group), or (ii) a nitrogen-containing functional group (if the linking group is a sulfur-containing functional group).

[0019] In particular, the inventors have discovered that the aforementioned objectives can be achieved by utilizing polymers, especially those modified with two or more ends, as defined above and preferably as defined throughout this document. Without being bound by theory, these polymers have the advantage of not exhibiting significant premature bonding during compounding. Instead, only one end undergoes premature bonding, while the other end remains chemically bonded before sulfur crosslinking (i.e., vulcanization). This still allows for very good handling during compounding. Simultaneously, the physicochemical properties of the corresponding rubber products, particularly tires, such as rolling resistance, abrasion resistance, and tensile stress, are improved (see examples below).

[0020] The subject matter of the invention is discussed in more detail below, wherein preferred embodiments of the invention are disclosed. Particularly preferred are combinations of two or more preferred embodiments to obtain particularly preferred embodiments. Accordingly, particularly preferred are sulfur-crosslinkable rubber compositions according to the invention that define two or more features of preferred embodiments of the invention.

[0021] The term "sulfur-crosslinkable" is well known to those skilled in the art and defines the rubber composition of the present invention as being curable (i.e., curable) in the presence of sulfur, such that the individual chains of the rubber polymer crosslink (i.e., interconnect) to obtain a cured rubber composition, i.e., a sulfur-vulcanized rubber composition. This process is called vulcanization, and the resulting product is commonly used in the production of a wide variety of rubber products. This also means that the sulfur-crosslinkable rubber composition according to the present invention has not yet undergone crosslinking, vulcanization, and curing.

[0022] In the context of this invention, as used herein, "phr" means "parts per hundred parts by weight of rubber" and is a standard unit used in the rubber industry to define the amount of different components in a rubber composition. The corresponding amount is given as parts by weight of the substance relative to the total mass of all the high molecular weight rubber present in the composition that is solid under ambient conditions and constitutes 100 phr.

[0023] (a) Packing material composition:

[0024] It has been found that the properties of sulfur-crosslinkable rubber compositions are affected by the selection of filler materials used in the filler component. The sulfur-crosslinkable rubber composition of the present invention comprises (a) a filler component in a total amount ranging from 1 to 350 phr. The filler component preferably comprises one or more filler materials, more preferably selected from the group consisting of: silica, carbon black, aluminum silicate, chalk, starch, magnesium oxide, titanium dioxide, rubber gel, graphite, graphene, hollow carbon fibers, and carbon nanotubes.

[0025] Our experiments show that excellent results were obtained using silica and / or carbon black. Therefore, the sulfur-crosslinkable rubber composition of the present invention is preferred, wherein the filler component comprises silica and / or carbon black as filler material.

[0026] Typically, the preferred embodiment of the present invention is the sulfur-crosslinkable rubber composition, which contains a filler component in a total amount ranging from 10 to 300 phr, preferably 15 to 260 phr, more preferably 20 to 220 phr, and even more preferably 25 to 180 phr.

[0027] In some cases, the sulfur-crosslinkable rubber composition of the present invention is preferred, wherein the filler component comprises carbon black as a filler material, the carbon black preferably being present in a total amount ranging from 10 to 300 phr, preferably 15 to 250 phr, more preferably 20 to 200 phr, even more preferably 25 to 150 phr, and even more preferably 30 to 100 phr. Preferably, in some cases, carbon black is the only filler material in the composition.

[0028] In some cases, the sulfur-crosslinkable rubber composition of the present invention is preferred, wherein the filler component comprises silica as a filler material, the silica preferably being present in a total amount ranging from 10 to 300 phr, preferably 20 to 270 phr, more preferably 30 to 240 phr, even more preferably 40 to 210 phr, and even more preferably 50 to 180 phr. Preferably, in some cases, silica is the only filler material in the composition.

[0029] Suitable silica is known to those skilled in the art and is disclosed, for example, in US 10273351 A1.

[0030] In some cases, a sulfur-crosslinkable rubber composition according to the invention is preferred, wherein the filler component comprises silica and carbon black (preferably in a weight ratio ranging from 100:1 to 1:100) as filler materials, wherein the filler component preferably comprises at least 0.01 phr carbon black. Therefore, in some cases, it is preferred that more silica than carbon black is present. In other cases, it is preferred that more carbon black than silica is present.

[0031] In some cases, it is preferred that the filler component contains silica as a filler material, wherein the total amount of silica is preferably 90 wt.% or more, more preferably 95 wt.% or more, and most preferably 98 wt.% or more based on the total weight of the filler component.

[0032] (b) The at least one modified conjugated diene-based polymer:

[0033] The sulfur-crosslinkable rubber composition of the present invention comprises (b) at least one modified conjugated diene-based polymer as defined above, preferably as defined throughout this document.

[0034] Typically, the at least one modified conjugated diene-based polymer, as defined in the context of this invention, exists as an alternative to (A), or (B), or a combination of (A) and (B) in a sulfur-crosslinkable rubber composition.

[0035] In the context of this document, "polymers based on conjugated dienes" generally refers to polymers based on (i.e., derived from, polymerized / copolymerized from) diene compounds (i.e., monomers) having conjugated carbon-carbon double bonds. In their polymeric state, they form the structural unit. Preferably, one or more polymer chains (except for functional groups) are wholly or at least primarily based on the structural unit, i.e., derived from the diene compound. Preferred diene compounds include isoprene, butadiene, and / or styrene.

[0036] More preferably, the at least one modified conjugated diene-based polymer is a modified styrene-butadiene-based polymer, a modified isoprene-based polymer and / or a modified butadiene-based polymer, even more preferably a modified styrene-butadiene-based polymer or a modified butadiene-based polymer, and most preferably a modified styrene-butadiene-based polymer.

[0037] The term "modified" indicates that the polymer additionally contains (i.e., includes in addition to the structural units derived from the conjugated diene compound) the aforementioned functional groups at the polymer ends (i.e., the tips). This means that the functional groups are at least monovalent functional groups. They modify the tips of the polymer chain. Since the polymer chain has tips in both alternatives (A) and (B), such monovalent functional groups are present in both alternatives.

[0038] In the context of this invention, "end" refers to all ends that can undergo modification by the functional groups described therein. For example, in the simplest case, the at least one modified conjugated diene-based polymer has a polymer chain with two ends at the beginning and end of the polymer chain. In this case, the entire polymer has as many ends as the single polymer chain. Furthermore, both ends are modified with functional groups, one of which is a nitrogen-containing functional group and the other is a sulfur-containing functional group. Thus, each type of functional group is present once. In the context of this invention, this configuration is particularly preferred for the sulfur-crosslinkable rubber compositions of this invention. This also represents the most preferred form of alternative (A).

[0039] In the case of two polymer chains, two scenarios are conceivable, both belonging to alternative (A). In the first scenario, one of the two polymer chains is a branch of the other polymer chain, meaning that one end of one polymer chain is connected to the main chain of the other polymer chain (in the context of alternative (A), this end is not modified by a functional group). This results in a total of three ends, all of which are modified by the aforementioned functional groups, at least one of which is a nitrogen-containing functional group and at least one of which is a sulfur-containing functional group. Thus, there are either two nitrogen-containing functional groups or two sulfur-containing functional groups. Furthermore, one polymer chain still has two ends (typically the main chain from which the branch originates) that are the corresponding ends of that polymer chain (meaning belonging to its corresponding polymer chain), one end of which is modified by a nitrogen-containing functional group and the other end of which is modified by a sulfur-containing functional group.

[0040] In the second scenario (still belonging to alternative (A)), the two polymer chains are linked together by backbone crosslinking, resulting in a total of four ends, all of which are modified by the aforementioned functional groups. Since each polymer chain has two corresponding ends (meaning belonging to its respective polymer chain), in each individual polymer chain, one end is modified by a nitrogen-containing functional group and the other end is modified by a sulfur-containing functional group. This results in a total of two nitrogen-containing functional groups and two sulfur-containing functional groups.

[0041] Furthermore, in the context of this invention, the at least one modified conjugated diene-based polymer may, in some cases, be present in the form of alternative (B). In this alternative, at least two polymer chains are present (i.e., preferably excluding a single polymer chain), preferably two, three, or four; most preferably two or three. The difference from alternative (A) is that the functional groups (preferably as defined throughout this document) not only modify the ends as monovalent functional groups, but also groups of the same kind are used as / act as at least divalent (i.e., divalent, trivalent, tetravalent, or higher valents; preferably divalent or trivalent) linking groups. The purpose is to link the individual polymer chains together, preferably via / through covalent bonds. Thus, such linking groups are subsequently integrated into the diene-based polymer, but are no longer end-modifiers in the finished polymer. Therefore, the at least one modified conjugated diene-based polymer according to alternative (B) comprises more than one polymer chain (the polymer chain comprising structural units derived from conjugated diene compounds), a monovalent functional group modified at the end of the polymer chain, and at least one divalent linking group binding the more than one polymer chain together.

[0042] In the context of this invention, the at least divalent linking group in alternative (B) is a nitrogen-containing or sulfur-containing functional group, provided that the terminal-modified monovalent functional group is not of the same category as the linking group. In other words, if the linking group is a nitrogen-containing functional group, then the terminal-modified functional group is a sulfur-containing functional group, and vice versa. For example, two polymer chains are linked to each other by a sulfur-containing functional group (referred to as "S-Si-1") that acts as a divalent linking group in alternative (B) (see also below and Table 2, modified conjugated diene-based polymers A-17, A-18, and A-28), wherein each of the two polymer chains is bonded at one end to a silicon atom of "S-Si-1". The remaining two ends of the polymer chains (one in each chain) are modified with a nitrogen-containing functional group. This results in a total of two monovalent nitrogen-containing functional groups at the ends and a single divalent sulfur-containing functional group within the diene-based polymer.

[0043] Regarding alternative (B), it is preferred that the linking group is a sulfur-containing functional group. More preferably, the linking group is a sulfur-containing functional group and the terminal-modified functional group is a monovalent nitrogen-containing functional group.

[0044] Typically, the functional groups defined in the context of this invention are preferably used as monovalent functional groups to modify the ends, or (if chemically applicable) as at least divalent linking groups to link at least two polymer chains together.

[0045] In some cases, the modified conjugated diene-based polymer of alternative (A) is preferred over alternative (B).

[0046] In the context of this invention, nitrogen-containing functional groups and sulfur-containing functional groups are each independent of each other. This preferably means having two nitrogen-containing functional groups, for example, as described above for the second case, where each nitrogen-containing functional group is either different or the same. As mentioned, the same principle applies to sulfur-containing functional groups. Furthermore, the type of nitrogen-containing functional group is independent of the type of sulfur-containing functional group, and vice versa.

[0047] Preferably, in the context of this invention, the nitrogen-containing functional group does not contain sulfur atoms.

[0048] Preferably, in the context of this invention, a sulfur-containing functional group (i) actually (i.e., must) contain at least one sulfur atom, and (ii) does not further contain a nitrogen atom or actually contains one or more additional nitrogen atoms. This means that a sulfur-containing functional group, as defined in the context of this invention, is defined by the presence of at least one sulfur atom, regardless of the presence or absence of an additional nitrogen atom. For example, the bis(dimethylamino)thiobenzophenone moiety (see below) is such a sulfur-containing functional group, although it also contains an amino group. Therefore, in the context of this invention, a thionone moiety is considered to be a sulfur-containing functional group due to the presence of a sulfur atom, regardless of the presence or absence of an additional amino atom. More preferably, the categories of compounds mentioned below that further define sulfur-containing functional groups are explicitly considered / defined as sulfur-containing functional groups, regardless of whether they have an additional nitrogen atom.

[0049] The synthesis of examples of modified conjugated diene-based polymers is explained in more detail in the Examples section below. Preferably, in at least one modified conjugated diene-based polymer, the conjugated diene compounds exhibit a statistical (i.e., random) distribution.

[0050] Preferably, the at least one conjugated diene-based polymer is a copolymer, i.e., it is based on two or more different diene compounds having conjugated double bonds, i.e., monomers with different chemical structures but still being conjugated dienes.

[0051] Preferably, the sulfur-crosslinkable rubber composition of the present invention, wherein,

[0052] - In the at least one modified conjugated diene-based polymer, the conjugated diene compound comprises a butadiene compound and / or (preferably) a styrene compound.

[0053] and / or

[0054] - The at least one modified conjugated diene-based polymer has a styrene content ranging from 0 to 50 wt.-%, preferably 5 to 50 wt.-%, more preferably 5 to 40 wt.-%, even more preferably 6 to 30 wt.-%, even more preferably 6 to 20 wt.-%, and most preferably 7 to 15 wt.-%.

[0055] and / or

[0056] - The at least one modified conjugated diene-based polymer has a vinyl content ranging from 10 to 80 wt.-%, preferably 15 to 65 wt.-%, more preferably 20 to 60 wt.-%, even more preferably 25 to 55 wt.-%, and most preferably 30 to 50 wt.-%.

[0057] The sulfur-crosslinkable rubber compositions of the present invention exhibit high affinity between the at least one modified conjugated diene-based polymer and the filler component. As a result, significantly improved properties are obtained after vulcanization, particularly improved rolling resistance, abrasion resistance, and tensile stress.

[0058] Preferably, the sulfur-crosslinkable rubber composition of the present invention comprises, in the at least one modified conjugated diene-based polymer, nitrogen-containing functional groups comprising

[0059] - An N-heterocyclic alkyl moiety having one, two, or three cyclic nitrogen atoms;

[0060] Preferably, it is a six-membered ring;

[0061] or

[0062] - The amino hydrocarbon moiety with a tertiary nitrogen atom (also called the amino hydrocarbon group moiety).

[0063] Preferably, the sulfur-crosslinkable rubber composition of the present invention comprises an N-heterocyclic alkyl moiety having one, two, or three cyclic nitrogen atoms.

[0064] - Piperidine fraction,

[0065] - Diazine moiety,

[0066] The preferred fraction is piperazine.

[0067] More preferably, the 1-methsilyl-piperazine moiety or the 1-methsilylalkyl-piperazine moiety,

[0068] Even more preferred are the 1-(trialkylsilyl)piperazine moiety or the 1-(3-(dialkyl(tert-alkoxy)silyl)propyl)piperazine moiety.

[0069] The most preferred moiety is either 1-(trimethylsilyl)piperazine or 1-(3-(dimethyl(tert-butoxy)silyl)propyl)piperazine;

[0070] and / or

[0071] - Triazine moiety,

[0072] The preferred moiety is 1,3,5-triazine.

[0073] The preferred N-heterocyclic alkyl moiety having one, two, or three cyclic nitrogen atoms is selected from the group consisting of compounds having formulas (1), (2), and (3).

[0074]

[0075] Each of them independently

[0076] - R 1 R 2 R 3 R 4 and R 5 Independently representing C1 to C10 alkylene groups,

[0077] C1 to C2 alkylene groups are preferred;

[0078] - X 1 Indicates a hydrocarbon group or -N(A) 3 )-,

[0079] Preferably C1 alkylene or -N(A) 3 )-;and

[0080] - A 1 A 2 and A 3 Indicates hydrogen, trialkylsilyl, or C1 to C20 hydrocarbon groups;

[0081]

[0082] in

[0083] - A 4It represents a C1 to C20(i+k)-valent hydrocarbon group, or a C1 to C20(i+k)-valent group having a nitrogen atom and no active hydrogen and bonded via a carbon atom to each of the silicon and nitrogen atoms in formula (3);

[0084] - R 6 and R 7 Each of them independently represents a C1 to C20 hydrocarbon group;

[0085] - n1 is an integer between 0 and 2;

[0086] - R 8 and R 9 Each of them independently represents a C1 to C10 hydrocarbon group;

[0087] - Each of i and k is an independent integer from 1 to 6, where i+k≤10;

[0088] - If there exists more than one R 6 If they are the same as or different from each other;

[0089] - If there exists more than one R 7 If they are the same as or different from each other;

[0090] - If there exists more than one R 8 If they are the same as or different from each other; and

[0091] - If there exists more than one R 9 If they are the same as or different from each other, then they are either the same as or different from each other.

[0092] In some cases, compounds having formula (1) are preferred, wherein R 1 and R 2 It is a C2 alkylene and X 1 It is a C1 alkylene group. In the context of this invention, this is the preferred piperidine moiety.

[0093] In some cases, compounds having formula (1) are preferred, wherein R 1 and R 2 It is a C2 alkylene and X 1 It is -N(A) 3 )- group and A 3 Preferably, it is a trialkylsilyl group. In the context of this invention, this is the preferred piperazine moiety.

[0094] In some cases, compounds having formula (3) are preferred, wherein R 8 and R 9 It is a C2 alkylene group, A 4It is a C2 to C4 alkylene group, i is 1, n1 is 1 or 2 (preferably 2), R 6 and R 7 It is independently a C1 to C5 alkyl group. In the context of this invention, this is also the preferred piperazine moiety.

[0095] Preferred are sulfur-crosslinkable rubber compositions, wherein the amino hydrocarbon moiety having tertiary nitrogen atoms comprises

[0096] - An N,N-(dialkyl)amino hydrocarbon moiety having one or more double bonds.

[0097] The preferred reaction compound is a reaction compound of 3-(dimethylamino)propyllithium and isoprene;

[0098] and / or

[0099] - N,N-bis(silyl)aminoalkyl-silane moiety

[0100] The preferred moiety is N,N-bis(trimethylsilyl)aminopropylmethyldiethoxysilane.

[0101] In the context of this invention, the term "part" preferably refers to the basic structure derived from or based on the functional group. Therefore, preferably, the part is a compound used for corresponding modification of the terminal portion.

[0102] In addition to N-functional groups, the at least one modified conjugated diene-based polymer also contains sulfur-functional groups.

[0103] Preferred are sulfur-crosslinkable rubber compositions, wherein the sulfur-containing functional groups in the at least one modified conjugated diene-based polymer are selected from the group consisting of:

[0104] - Thionylpropane moiety;

[0105] - Carbon disulfide portion;

[0106] - Hydroxyl thiol moiety,

[0107] Preferred olefin thiol moiety,

[0108] The propylene mercaptan fraction is the preferred option;

[0109] - Sulfide portion,

[0110] The preferred aromatic sulfide portion,

[0111] The preferred option is the phenyl vinyl sulfide moiety;

[0112] - Thioester portion;

[0113] - Dithioester moiety,

[0114] The preferred aromatic disulfide fraction is...

[0115] The cumyl dithiobenzoate moiety is the preferred option;

[0116] - Thione moiety,

[0117] The preferred aromatic thion fraction is...

[0118] The most preferred moiety is the bis(dimethylamino)thiobenzophenone fraction.

[0119] or

[0120] Preferred branched aliphatic thion moiety,

[0121] The di-tert-butylthione moiety is the preferred option;

[0122] - Dithiane moiety,

[0123] The preferred alkyl dithiane moiety is...

[0124] The methyl-1,3-dithiane moiety is preferred;

[0125] - Dithiopentane moiety;

[0126] - Thiophene fraction;

[0127] and / or

[0128] - A dialkyltin (IV) disulfide moiety or a dialkylsilyl disulfide moiety, each comprising an alkoxysilyl group.

[0129] The preferred moiety is dialkyltin(IV) bis(alkoxysilylalkyl sulfide).

[0130] Very preferably, the sulfur-containing functional group comprises a thiocyclopropane moiety or a thioketone moiety, preferably as defined above as the preferred thiocyclopropane moiety or thioketone moiety.

[0131] The inventors have found that particularly good results were obtained using the more specific functional groups described above (see also the examples below).

[0132] Preferably, the dialkyltin (IV) disulfide moiety and the dialkylsilyl disulfide moiety (each comprising an alkoxysilyl group) are very preferably at least divalent functional groups used as linking groups in alternative (B), and less preferably as monofunctional groups in alternative (A).

[0133] Preferred are sulfur-crosslinkable rubber compositions, wherein the at least one modified conjugated diene-based polymer has a sulfur content in the range of 50 to 800 ppm, preferably 65 to 675 ppm, more preferably 80 to 550 ppm, even more preferably 95 to 425 ppm, even more preferably 110 to 300 ppm, and most preferably 125 to 250 ppm based on the total weight of the polymer. In the context of this invention, the sulfur content is determined using combustion ion chromatography (combustion IC) analysis with a measuring instrument AQF-2100H (Nittoseiko Analytech Co., Ltd.) under the following conditions:

[0134] - Combustion temperature: Inlet: 900°C, Outlet: 1000°C

[0135] - Gas flow rate: Argon 200 mL / min, Oxygen 400 mL / min

[0136] - Humidification: 0.23 mL / min, internal standard (PO4): 20 mg / kg

[0137] - Absorbent solution (hydrogen peroxide in water): 900 mg / kg; Absorbent solution volume: 5 mL; Final dilution volume of absorbent solution: 10 mL

[0138] - Column: IonPac TM AS18 (Thermo Fisher Scientific Inc.)

[0139] - Eluent: 30.5 mM KOH aqueous solution

[0140] - Flow rate: 1 mL / min

[0141] - Detector: Suppressed conductivity detector, SRS

[0142] - Current: 76 mA

[0143] - Sample quantity: Weigh 30 mg of the corresponding modified conjugated diene-based polymer into the sample boat and add combustion accelerant (WO3).

[0144] Preferred are sulfur-crosslinkable rubber compositions, wherein the at least one modified conjugated diene-based polymer has a nitrogen content in the range of 25 to 500 ppm, preferably 50 to 420 ppm, based on the total weight of the polymer. In the context of this invention, the nitrogen content is determined according to JIS K 2609: 1998 “Crude petroleum and petroleum products - Determination of nitrogen content”. This means that a sample of the corresponding modified conjugated diene-based polymer is completely pyrolyzed under an argon flow in a trace total nitrogen analyzer (instrument: TN-2100H (Mitsubishi Chemical Analytech, Co., Ltd.)), and then oxidized and burned with oxygen. The generated nitric oxide is oxidized by ozone gas under dehydration conditions, and the emission intensity is measured between 590 and 2500 nm. The nitrogen content is determined by the area under the emission intensity curve.

[0145] Preferred are sulfur-crosslinkable rubber compositions according to the invention, wherein the at least one modified conjugated diene-based polymer has a weight-average molecular weight M in the range of 50,000 to 2,000,000 g / mol, preferably 70,000 to 1,500,000 g / mol, more preferably 90,000 to 1,000,000 g / mol, even more preferably 110,000 to 750,000 g / mol, even more preferably 130,000 to 500,000 g / mol, and most preferably 130,000 to 300,000 g / mol. w .

[0146] In the context of this invention, the weight-average molecular weight M mentioned above... w The determination was performed according to BS ISO 11344:2004 at 40°C by gel permeation chromatography (GPC) (using tetrahydrofuran (THF) as the eluent).

[0147] Preferred is the sulfur-crosslinkable rubber composition of the present invention, wherein the at least one modified conjugated diene-based polymer according to (b) is present in a total amount ranging from 10 to 99 phr, preferably 25 to 98 phr, more preferably 40 to 97 phr. Very preferably, the total amount is greater than 40 phr. Preferably, the modified conjugated diene-based polymer according to (b) is the main polymeric substance in the sulfur-crosslinkable rubber composition.

[0148] (c) Diene-based rubber polymers, different from (b):

[0149] The sulfur-crosslinkable rubber composition according to the present invention may contain other diene rubber compounds. Preferably, the sulfur-crosslinkable rubber composition of the present invention further comprises...

[0150] (c) Unlike the diene-based rubber polymers of (b), which are preferably selected from the group consisting of: natural polyisoprene (NR), synthetic polyisoprene (IR), polybutadiene (BR; butadiene rubber), styrene-butadiene copolymer (SBR, styrene-butadiene rubber), butyl rubber (IIR) and halogenated butyl rubber.

[0151] Preferably, the styrene-butadiene copolymer (SBR) includes solution-polymerized styrene-butadiene rubber (SSBR), emulsion-polymerized styrene-butadiene rubber (ESBR), or mixtures thereof.

[0152] Very preferably, the diene-based rubber polymers, unlike those in (b), include natural polyisoprene (NR) and / or polybutadiene (BR), with natural polyisoprene (NR) being the most preferred.

[0153] (d) Other components:

[0154] The sulfur-crosslinkable rubber composition according to the invention preferably contains additional compounds (i.e., in addition to those defined throughout (a), (b) and (c)).

[0155] Preferably, the sulfur-crosslinkable rubber composition according to the invention further comprises one or more of the following:

[0156] i) An aging stabilizer (also known as an antioxidant), preferably comprising p-phenylenediamine and / or dihydroquinoline; more preferably selected from the group consisting of: N-phenyl-N'-(1,3-dimethylbutyl)-p-phenylenediamine (6PPD), N,N'-diphenyl-p-phenylenediamine (DPPD), N-(1-phenylethyl)-N'-phenyl-p-phenylenediamine (SPPD), N,N'-xylyl-p-phenylenediamine (DTPD), N-(1,4-dimethylpentyl)-N'-phenyl-p-phenylenediamine (7PPD), N-isopropyl-N'-phenyl-p-phenylenediamine (IPPD) and 2,2,4-trimethyl-1,2-dihydroquinoline (TMQ);

[0157] ii) An activator, preferably comprising zinc compounds (including zinc complexes) and / or fatty acids; very preferably comprising zinc oxide, stearic acid and / or zinc ethylhexanoate;

[0158] iii) Coupling agents (also known as binding compounds) for bonding filler materials (particularly for carbon black and silica); preferably comprising S-(3-aminopropyl)-thiosulfate, its metal salt (particularly for bonding carbon black) and / or silane coupling agents (particularly for bonding silica);

[0159] iv) Wax, preferably ozone-protective wax;

[0160] v) Resin, preferably a tackifying resin, which is not a plasticizer resin;

[0161] vi) Plasticizing aids, preferably including 2,2'-dibenzoamide diphenyl disulfide (DBD);

[0162] vii) Processing aids, which preferably include fatty acid esters;

[0163] viii) Softeners (also known as plasticizers), which preferably include oils and / or resins (preferably oils);

[0164] ix) an accelerator, preferably selected from the group consisting of: thiazole compounds, mercapto-containing compounds, sulfenamide compounds, thiocarbamate compounds, thiuram compounds, thiophosphate compounds, thiourea compounds, xanthate compounds, and guanidine compounds;

[0165] and / or

[0166] x) Sulfur and sulfur donor compounds, preferably thiuram disulfide and / or thiuram tetrasulfide.

[0167] Generally preferred are sulfur-crosslinkable rubber compositions according to the invention, which contain the additional components according to (d) in a total amount ranging from 1 to 300 phr, preferably 2 to 200 phr, more preferably 3 to 100 phr, even more preferably 4 to 80 phr, and most preferably 5 to 60 phr. In this context, total amount refers to the sum of i) to x).

[0168] Preferably, the aging stabilizer according to i) above is present in a total amount ranging from 0.1 phr to 15 phr, preferably 0.5 to 10 phr, and most preferably 1 to 5 phr.

[0169] Preferably, the activator according to ii) above is present in a total amount ranging from 0.1 phr to 20 phr, preferably from 0.5 to 15 phr, and most preferably from 1 to 10 phr.

[0170] There are no particular limitations on the silane coupling agent (see iii above). However, preferred silane coupling agents include bifunctional organosilanes, wherein the silicon atom is bonded to an alkyl, alkoxy, cycloalkoxy, and / or phenoxy group. Preferably, the silane coupling agent additionally contains another functional group, preferably an SH group (i.e., the silane coupling agent is a mercaptosilane).

[0171] More preferred silane coupling agents include 3-mercaptopropyltriethoxysilane, 3-thiocyanopropyltrimethoxysilane, 3,3'-bis(triethoxysilylpropyl) polysulfides having 2 to 8 sulfur atoms (most preferably 3,3'-bis(triethoxysilylpropyl)tetrasulfide (TESPT) and / or its disulfide (TESPD)) and / or mixtures having different amounts of sulfur atoms. TESPT and TESPD are particularly preferred.

[0172] Preferred silane coupling agents additionally or alternatively include those disclosed in WO 2008 / 083241 A1, WO 2008 / 083242 A1, WO 2008 / 083243 A1 and WO 2008 / 083244 A1.

[0173] Preferably, the total amount of coupling agent according to iii) ranges from 1 to 50 phf (parts by weight per 100 parts of filler), more preferably 2 to 40 phf, more preferably 3 to 30 phf, even more preferably 4 to 20 phf, and most preferably 5 to 15 phf. This is most preferably applicable when the silane coupling agent is the only coupling agent in the sulfur-crosslinkable rubber composition.

[0174] Preferably, the wax described above according to iv) is present in a total amount ranging from 0.1 phr to 15 phr, preferably 0.5 to 10 phr, and most preferably 1 to 5 phr.

[0175] Regarding the softener described in viii) above, preferred oils include mineral oils and / or vegetable oils. Preferred vegetable oils include low-erucic acid canola oil. Preferred mineral oils include mild extraction solvates (MES), distilled aromatic extracts (DAE), residual aromatic extracts (RAE), treated distillate aromatic extracts (TDAE), and rubber-based liquid oils (RTL oils).

[0176] Preferably, the softener described above according to viii) is present in a total amount ranging from 1 phr to 60 phr, preferably 5 to 50 phr, and most preferably 10 to 40 phr.

[0177] Regarding the accelerators described above according to ix), sulfenamide compounds are preferred. Very preferably, the accelerators include N-cyclohexyl-2-benzothiazole sulfenamide (CBS), N,N-dicyclohexylbenzothiazole-2-sulfenamide (DCBS), benzothiazole-2-sulfenylmorpholine (MBS), N-tert-butyl-2-benzothiazole sulfenamide (TBBS), and diphenylguanidine (DPG).

[0178] Preferably, the promoter according to ix) is present in a total amount ranging from 0.1 phr to 15 phr, preferably from 0.25 to 10 phr, and most preferably from 0.5 to 5 phr.

[0179] There are no particular limitations on the sulfur and sulfur donor compounds described above according to x), as long as they provide sulfur. In some cases, the sulfur donor compounds overlap with promoter compounds from the same compound class. Preferred sulfur donor compounds are selected from the group consisting of: thiuram disulfides, thiuram tetrasulfides, dithiophosphates, and polysulfides. Preferred thiuram disulfides include tetrabenzylthiuram disulfide (TBzTD), tetramethylthiuram disulfide (TMTD), and / or tetraethylthiuram disulfide (TETD). Preferred thiuram tetrasulfides include bis(diisopropyl)thiophosphoryl disulfide (DIPDIS), zinc dichloroacyl dithiuram phosphate, and / or alkyl zinc dithiuram phosphate. Preferred polysulfides include bis(O,O-2-ethylhexyl-thiophosphoryl) polysulfides, diaryl polysulfides, and / or dialkyl polysulfides.

[0180] Preferably, the sulfur and sulfur donor compound described above according to x) are present in a total amount ranging from 0.1 phr to 15 phr, preferably from 0.25 to 10 phr, and most preferably from 0.5 to 5 phr.

[0181] In order to obtain a sulfur-vulcanized rubber composition, additional compounds such as ix) accelerators and x) sulfur and sulfur donor compounds are required before the sulfur crosslinkable rubber composition is vulcanized.

[0182] Vulcanized rubber compositions:

[0183] The present invention also relates to a sulfur-vulcanized rubber composition that can be obtained by sulfur-vulcanization of a sulfur-crosslinkable rubber composition according to the present invention, preferably as described herein.

[0184] Preferably, the foregoing description of the sulfur-crosslinkable rubber composition according to the present invention (including its preferred, more preferred, most preferred, etc. examples and features) is also applicable to the sulfur-vulcanized rubber composition of the present invention with necessary modifications.

[0185] Necessarily, the vulcanization of the sulfur-crosslinkable rubber composition is carried out in the presence of sulfur and / or sulfur donor compounds, and preferably also in the presence of a vulcanization accelerator. As mentioned above, in some cases, the accelerator is also a sulfur donor compound.

[0186] In some cases, vulcanization delay agents are used to better control vulcanization.

[0187] Typically, all compounds that affect vulcanization—sulfur, sulfur donor compounds, accelerators, etc.—are also referred to as the vulcanization system or curing package. They are usually added to the pre-mixed sulfur-crosslinkable rubber composition in a subsequent step of compounding, followed by other optional process steps. Vulcanization itself is usually carried out at elevated temperatures, where suitable process parameters are well-established industrially.

[0188] In view of the above, this document also relates to the use of the sulfur-crosslinkable rubber composition according to the invention for obtaining a sulfur-vulcanized rubber composition by vulcanization.

[0189] Furthermore, this document also relates to a method for preparing sulfur-crosslinkable rubber compositions or sulfur-vulcanized rubber compositions according to the present invention, the method comprising the following steps:

[0190] (A) Providing or producing a filler component, which is preferably as described herein and most preferably as described herein;

[0191] (B) Providing or producing at least one modified conjugated diene-based polymer, which is preferred as described herein and most preferably as described herein;

[0192] (C) Optionally provided

[0193] (c) A diene-based rubber polymer, different from the polymer provided and produced in step (B), preferably as described herein.

[0194] (d) Other components, which are preferred as described herein and most preferably as described herein;

[0195] (D) In ​​one or more steps, the filler component from step (A), the at least one modified conjugated diene-based polymer from step (B), and optionally the components provided in step (C) are compounded to obtain a sulfur-crosslinkable rubber composition or a sulfur-vulcanized rubber composition.

[0196] The foregoing content regarding the method of the present invention, the sulfur-crosslinkable rubber composition of the present invention, and the sulfur-vulcanized rubber composition of the present invention, preferably with necessary modifications, are also applicable to the method of the present invention.

[0197] In the above method, step (D) is preferably carried out in more than one step (preferably in several separate mixing steps) in order to mix all the ingredients provided in steps (A), (B) and optionally (C).

[0198] Furthermore, in the above methods, the presence of the vulcanization system or curing package determines whether a sulfur-crosslinkable rubber composition or a sulfur-vulcanized rubber composition is obtained.

[0199] The present invention also relates to further products obtained from sulfur-vulcanized rubber compositions. Therefore, the present invention also relates to a rubber product comprising a sulfur-vulcanized rubber composition according to the present invention, most preferably, as described herein, a sulfur-vulcanized rubber composition preferred throughout.

[0200] Preferably, the above description of the sulfur-vulcanized rubber composition, with necessary modifications, also applies to the rubber products of the present invention.

[0201] Preferably, the sulfur-cured rubber composition according to the invention is included in the rubber product, preferably in the whole product or at least in a part of the product.

[0202] In some cases, the rubber products of the present invention as industrial rubber products are preferred, preferably selected from the group consisting of: corrugated pipes, belts (preferably conveyor belts and cushioning belts), air springs and shoe soles.

[0203] The present invention also relates to a tire, preferably a vehicle tire, and most preferably a pneumatic vehicle tire, wherein at least a portion of the tire contains a rubber product according to the present invention.

[0204] The above description of the sulfur-crosslinkable rubber composition and the sulfur-vulcanized rubber composition of the present invention is also preferably applicable to the tires of the present invention with necessary modifications.

[0205] As mentioned, vehicle tires are preferably pneumatic tires. However, in some cases, vehicle tires are preferably solid rubber tires.

[0206] Generally, in the context of this invention, there is no limitation on the type of vehicle. Preferably, the tires are selected from the group consisting of: truck tires, passenger car tires, van tires, bicycle tires, commercial vehicle tires, and special vehicle tires.

[0207] This document also relates to the use of at least one modified conjugated diene-based polymer, as described herein and preferably as preferred, in a sulfur-crosslinkable rubber composition, preferably in a sulfur-crosslinkable rubber composition according to the invention (preferably as described herein), for reducing the rolling resistance of vehicle tires produced from sulfur-crosslinkable rubber compositions.

[0208] Preferably, the foregoing description of sulfur-crosslinkable rubber compositions, with necessary modifications, also applies to this use. Detailed Implementation

[0209] The invention is described in more detail below through experiments.

[0210] A) Synthesis of modified conjugated diene-based polymers:

[0211] Comparison Example 1

[0212] Cyclohexane (2,500 g), 2,2-bis(tetrahydrofurfuryl)propane (0.8644 mmol) as a vinyl content regulator (randomizer), piperidine (4.331 mmol) as an initiation terminal-modifier, and styrene (50 g) and 1,3-butadiene (400 g) as monomers were added to a nitrogen-purged autoclave reactor (capacity: 5 L). The temperature of the reactor contents was adjusted to 20°C, and n-butyllithium (5.62 mmol) as a polymerization initiator was added to the reactor to initiate polymerization. The polymerization temperature was increased from room temperature to 75°C over 25 minutes.

[0213] After the percentage conversion of polymerization reaches 99% (i.e., 25 minutes after the start of polymerization), 1,3-butadiene (50 g) is added over 5 minutes.

[0214] Subsequently, N,N-bis(trimethylsilyl)aminopropylmethyldiethoxysilane (an amino hydrocarbon moiety having a tertiary nitrogen atom; in this example it may also be referred to as “N-Si-1”) (4.322 mmol) was added, and the mixture was allowed to react for 15 minutes.

[0215] 2,6-Di-tert-butyl-p-cresol (4.40 g) was added to the polymer solution thus obtained. The solvent was then removed by steam stripping, and the resulting material was dried by hot rollers at a temperature controlled at 110°C to obtain the modified conjugated diene-based polymer A-1 (see Table 1).

[0216] Compare Examples 2 to 5, and Examples 1 to 17, 19 and 20

[0217] The polymerization, solvent removal, and drying procedures performed in Comparative Example 1 were repeated, except that the types and amounts of reagents used were changed to the values ​​shown in Table 1, to obtain modified conjugated diene-based polymers A-2 to A-5, A-9 to A-25, A-27, and A-28.

[0218] Comparison Example 6

[0219] The polymerization, solvent removal, and drying procedures performed in Comparative Example 4 were repeated, except that the reaction was carried out for 15 minutes in the presence of cyclothioethane; n-octanoyl chloride (4.322 mmol) was added before the addition of 2,6-di-tert-butyl-p-cresol (4.40 g); and the reaction was carried out for an additional 10 minutes to obtain the modified conjugated diene-based polymer A-6.

[0220] Comparison Example 7

[0221] The polymerization, solvent removal, and drying procedures performed in Comparative Example 1 were repeated, except that 1-(3-(dimethyl(tert-butoxy)silyl)propyl)piperazine (piperazine moiety; also referred to as "Si-N-1" in the example) (4.331 mmol) and divinylbenzene (2.161 mmol) were used to replace piperidine and N-Si-1, respectively, to obtain the modified conjugated diene-based polymer A-7.

[0222] Comparison Example 8

[0223] Cyclohexane (2,500 g), 2,2-bis(tetrahydrofurfuryl)propane (0.8644 mmol) as a vinyl content regulator (randomizer), and styrene (50 g) and 1,3-butadiene (400 g) as monomers were added to a nitrogen-purged autoclave reactor (capacity: 5 L). The temperature of the reactor contents was adjusted to 20°C. An initiator solution was prepared separately by reacting n-butyllithium (11.24 mmol) and divinylbenzene (5.62 mmol) in cyclohexane (50 g) using a nitrogen-purged pressure vessel (100 mL). The initiator solution was added to the autoclave reactor to initiate polymerization. The polymerization temperature was increased from room temperature to 75°C over approximately 25 minutes.

[0224] After the percentage conversion of polymerization reached 99% (i.e., 25 minutes after the start of polymerization), 1,3-butadiene (50 g) was added over 5 minutes. Subsequently, cyclothioethane (8.644 mmol) was added, and the mixture was allowed to react for 15 minutes.

[0225] 2,6-Di-tert-butyl-p-cresol (4.40 g) was added to the polymer solution thus obtained. The solvent was then removed by steam stripping, and the resulting material was dried by hot rollers at a temperature controlled at 110°C to obtain the modified conjugated diene-based polymer A-8.

[0226] Example 18

[0227] The polymerization, solvent removal, and drying procedures in Example 1 were repeated, except that the reaction was carried out for 15 minutes in the presence of cyclothioethane; n-octanoyl chloride (4.322 mmol) was added before the addition of 2,6-di-tert-butyl-p-cresol (4.40 g); and the reaction was carried out for another 10 minutes to obtain the modified conjugated diene-based polymer A-26.

[0228] Tables 1 and 2 show the physical properties of the modified conjugated diene-based polymers A-1 to A-28 obtained after solvent removal.

[0229]

[0230]

[0231] The detailed information of the compounds listed in Tables 1 and 2 is as follows.

[0232] Initiator end modifier:

[0233] Si-N-1 represents 1-(3-(dimethyl(tert-butoxy)silyl)propyl)piperazine (piperazine moiety in the context of this invention);

[0234] AI-200CE2 indicates the reaction product of 3-(dimethylamino)propyllithium and isoprene [reaction ratio: isoprene / 3-(dimethylamino)propyllithium = 2 / 1 (molar ratio)] (an amino hydrocarbon moiety having a tertiary nitrogen atom, particularly an N,N-(dialkyl)amino hydrocarbon moiety having one or more double bonds), a product of FMC Corporation.

[0235] Termination end modifier:

[0236] N-Si-1 represents N,N-bis(trimethylsilyl)aminopropylmethyldiethoxysilane (an amino hydrocarbon moiety having a tertiary nitrogen atom, particularly the N,N-bis(silyl)aminoalkyl-silane moiety).

[0237] S-Si-1 represents a compound represented by the following formula (S-Si-1; dialkyltin(IV)bis(alkoxysilylalkyl sulfide)).

[0238]

[0239] Example 21

[0240] A mixture of 1,3-butadiene (26.6 g / min) and styrene (2.95 g / min) as monomers; cyclohexane (180.2 g / min) as solvent; tetrahydrofuran (0.4 g / min) as vinyl content regulator (randomizer); and a mixture of n-butyllithium (as polymerization initiator) and Si-N-1 (as initiation-end modifier) ​​(molar ratio: 1 / 1) (0.25 mmol / min) was continuously fed into a nitrogen-purged autoclave reactor (capacity: 50 L) (i.e., the first-stage reactor) at the feed rate specified above. The temperature inside the reactor was maintained at 75°C.

[0241] The polymer solution obtained in the first-stage reactor was continuously discharged at a rate of 210.2 g / min. Cyclothioethane was added to the discharged polymer solution at a rate of 0.20 mmol / min, and the mixture was continuously fed into a second-stage reactor where it was reacted. At the outlet of the second-stage reactor, di-tert-butyl-p-cresol was added to adjust its amount to 0.88 parts by mass / 100 parts by mass of polymer. The resulting polymer solution was subjected to steam stripping to remove the solvent, and the product was dried by hot rollers at a temperature controlled at 110°C to obtain the modified conjugated diene-based polymer A-29. The physical properties of the modified conjugated diene-based polymer A-29 are as follows.

[0242] The combined styrene content is 10%, vinyl content is 39%, Mw is 960,000, Mw / Mn ratio is 1.6, nitrogen content is 68 ppm, and sulfur content is 133 ppm.

[0243] B) Production of sulfur-crosslinkable rubber compositions:

[0244] Compare Examples 1 to 8 and Examples 1 to 21

[0245] The components (ingredients) are blended according to the formulations shown in Tables 3 and 4, and each mixture is melt-kneaded to produce the target polymer composition. The melt kneading is performed as follows.

[0246] The first stage of kneading was performed using a batch mixer (Labo Plastomill, a product of Toyo Seiki Seisaku-sho, Ltd.) equipped with a temperature controller. The kneading temperature was controlled at 100°C, and each modified conjugated diene-based polymer, polybutadiene rubber (BR), filler oil, silica, carbon black, silane coupling agent, stearic acid, antioxidant, and zinc oxide were kneaded at a rotation speed of 60 rpm for 4 minutes.

[0247] Next, a second stage of kneading was performed. The kneaded product obtained from the first stage kneading operation was cooled to room temperature. A vulcanization accelerator and sulfur were added to the cooled product. The resulting mixture was fed into a mixer. While maintaining the kneading temperature at 70°C, the mixture was kneaded at 60 rpm for 1.5 minutes to obtain polymer compositions (Q-1 to Q-29). In all cases, the temperature of the kneaded product discharged from the mixer was 100°C or lower. Subsequently, each of the produced compositions was vulcanized and molded at 160°C for a specific time using a vulcanizing press to produce vulcanized rubber compositions and obtain corresponding samples. These samples were further evaluated in terms of their physical properties. The results are shown in Tables 3 and 4.

[0248] Examples 22 and 23 and comparative examples CE9 to CE14

[0249] Examples 22 and 23, as well as comparative examples CE9 to CE14 (Table 5), were compounded similarly to those described above and according to standard industrial procedures, wherein all components except the vulcanization system (sulfur and compounds affecting vulcanization) were first compounded in a first stage (basic compounding stage). The final mixture was produced by adding the vulcanization system in a second stage (finished product compounding stage), wherein the compounding was carried out at 90°C to 120°C.

[0250] The appropriate compositions were used to produce samples by vulcanization at 160°C under pressure, with approximately 10 minutes for carbon black-containing compositions and approximately 14 minutes for silica-containing compositions. These samples were used to determine the physical properties as mentioned and summarized in Table 6.

[0251] C) Methods for evaluating the physical properties of the composition:

[0252] Rolling resistance (3% tan δ at 50°C; Tables 3 and 4)

[0253] The ratio (tan δ at 50°C); that is, the loss modulus G'' / storage modulus G' of each vulcanized rubber sample was determined by a shear-type dynamic spectrometer (TA Instruments) at an angular velocity of 100 radians / second and at 50°C with a shear strain of 3%. The measured value is expressed as an exponent of the rolling resistance (of 100) relative to the sample of Comparative Example 1. The larger this value, the more suitable (i.e., the smaller) the rolling resistance and fuel efficiency.

[0254] Rolling resistance (tan δ at 70°C; Table 6)

[0255] In this case, the rolling resistance refers to the maximum value of the loss factor tangent δ as the maximum value of the strain scan from dynamic mechanical measurements at 70°C, according to DIN 53513.

[0256] Strength ((TBxEB) / 2; Tables 3 and 4)

[0257] The vulcanized rubber samples were subjected to a tensile test according to JIS K6251:2010. In this test, the test specimens were dumbbell-shaped (No. 3), and the tensile stress at break (TB, MPa) and elongation at break (EB, %) were measured at room temperature. The strength was provided by half the tensile product (=(TB x EB)). The measured value was expressed as an exponent of the strength (with 100) relative to the sample of Comparative Example 1. The larger the value, the higher the strength.

[0258] Shore A hardness (Table 6)

[0259] Shore A hardness is determined at room temperature using a hardness tester based on DIN 53505.

[0260] Resilience (Table 6)

[0261] Resilience was determined at 70°C according to DIN 53 512 (elasticity at 70°C).

[0262] Abrasion resistance (DIN abrasion; Tables 3 and 4)

[0263] The abrasion resistance of the vulcanized rubber samples was determined according to JIS K6264 under a load of 10 N and at 25°C using a DIN abrasion tester (a product of Toyo Seiki Co., Ltd.). The measured value is expressed as an index of abrasion resistance (out of 100) relative to the sample of Comparative Example 1. The higher the value, the better the abrasion resistance.

[0264] The wear values ​​shown in Table 6 were measured at room temperature according to DIN / ISO 4649. The lower the value, the better the wear.

[0265] Tables 3 (Q1-Q14) and 4 (Q15-Q29)

[0266]

[0267] The detailed information of the compounds listed in Tables 3 and 4 is as follows.

[0268] 1) Trade name "BR01", ENEOS Materials Corporation

[0269] 2) Product name "ZEOSIL 1165MP", a product of Solvay.

[0270] 3) Product name "DIABLACK N330", manufactured by Mitsubishi Chemical Corporation.

[0271] 4) Product name "Si75", a product of Evonik.

[0272] 5) Process oil, trade name "T-DAE", a product of ENEOS Materials Co., Ltd.

[0273] 6) Ozonone 6C, a product of Seiko Chemical Co., Ltd.

[0274] 7) Product with the trade name "Nocceler D" by Ouchi Sinko Chemical Industrial Co., Ltd.

[0275] 8) Product named "Nocceler CZ-G" by Ouchi Shinsei Chemical Industry Co., Ltd.

[0276] As is clear from Tables 1 to 4, any of the modified conjugated diene-based polymers obtained from Examples 1 to 21 can produce crosslinks that exhibit a good balance of rolling resistance, abrasion resistance, and strength.

[0277] The other experimental compositions were tested, as summarized in Table 5 below. Their physical properties are summarized in Table 6 below.

[0278] Table 5; “CE” indicates “Comparative Example”; “E” indicates “Example”:

[0279]

[0280] The detailed information of the compounds listed in Table 5 is as follows.

[0281] #1 Natural rubber (NR), TSR type

[0282] #2 SBR (unfunctionalized styrene-butadiene copolymer)

[0283] #3 N220, Orion Corporation

[0284] #4 VN3, Evonik

[0285] #5 TESPD, Evonik

[0286] #6 For CE1 to CE3 and E22, a combination of 6 PPD, TMQ, and DTPD; for CE4 to CE6 and E23, 6 PPD.

[0287] #7 TDAE

[0288] #8 For CE1 to CE3 and E22, TBBS; for CE4 to CE6 and E23, a combination of DPG and CBS.

[0289] Table 6 shows the physical properties of the compositions based on Table 5.

[0290]

[0291] As shown in Table 6, all examples clearly demonstrate that the use of modified conjugated diene-based polymers did not compromise the relatively good Shore A hardness. Comparing Example E22 with its corresponding comparative Examples CE9 to CE11, a very narrow range of 62 to 64 ShA was maintained. E23 obtained correspondingly similar results compared to CE12 to CE14 (range 63 to 68 ShA).

[0292] In contrast, resilience at 70°C increased significantly in each group of instances. E22 achieved a maximum of 58% compared to the lower values ​​obtained with comparative instances CE9 to CE11 (only in the range of 48% to 55%). A similar pattern was observed for E23 (54%) compared to CE12 to CE14 (only in the range of 43% to 51%).

[0293] Furthermore, the tangent δ at 70°C was also significantly improved (i.e. reduced). E22 obtained a minimum value of 0.108 compared to the significantly higher values ​​obtained with comparative examples CE9 to CE11 (only in the range of 0.124 to 0.148). Similarly, a similar pattern can be seen for E23 (0.115) compared to CE12 to CE14 (only in the range of 0.141 to 0.166).

[0294] The combination of increased elasticity and decreased tangent δ impressively demonstrates that significantly improved rolling resistance is achieved with the composition according to the invention.

[0295] At the same time, wear is also improved (see comparison of E22 with CE9 to CE11) or at least not significantly damaged (see comparison of E23 with CE12 to CE14).

[0296] In addition, Example E22 was repeated, except that a modified conjugated diene-based polymer A-15 was used instead of A-9, resulting in Example "E22a". The following were obtained for E22a: Shore A hardness: 64; elasticity (70°C): 60, Tan δ (70°C): 0.100; and abrasion (room temperature): 71.

[0297] Similarly, Example E23 was repeated, except that a modified conjugated diene-based polymer A-22 was used instead of A-9, resulting in Example "E23a". For E23a, the following were obtained: Shore A hardness: 68; elasticity (70°C): 57; Tan δ (70°C): 0.103; and abrasion (room temperature): 70.

Claims

1. A sulfur-crosslinkable rubber composition comprising... (a) Packing material components ranging from 1 to 350 phr in total quantity, and (b) at least one modified conjugated diene-based polymer having One or more polymer chains, each comprising a structural unit derived from a conjugated diene compound, wherein the ends of each polymer chain are modified with functional groups, which are either nitrogen-containing or sulfur-containing functional groups. The condition is A) - At least one of these ends is modified with a nitrogen-containing functional group and at least another of these ends is modified with a sulfur-containing functional group, and - In each polymer chain with two corresponding ends, one end is modified with a nitrogen-containing functional group and the other end is modified with a sulfur-containing functional group; or B) - Two, three, or more than three polymer chains in one polymer chain are linked together by nitrogen-containing or sulfur-containing functional groups that act as linking groups, and - The functional group that modifies the ends of the two, three or more polymer chains is (i) a sulfur-containing functional group if the linking group is a nitrogen-containing functional group, or (ii) a nitrogen-containing functional group if the linking group is a sulfur-containing functional group.

2. The sulfur-crosslinkable rubber composition according to claim 1, wherein, The filler composition contains silica and / or carbon black as filler materials.

3. The sulfur-crosslinkable rubber composition according to claim 1 or 2, comprising the filler component in a total amount ranging from 10 to 300 phr, preferably 15 to 260 phr, more preferably 20 to 220 phr, and even more preferably 25 to 180 phr.

4. The sulfur-crosslinkable rubber composition according to any one of claims 1 to 3, wherein, - In the at least one modified conjugated diene-based polymer, the conjugated diene compound comprises a butadiene compound and / or a styrene compound. and / or - The at least one modified conjugated diene-based polymer has a styrene content ranging from 0 to 50 wt.-%, preferably 5 to 50 wt.-%, more preferably 5 to 40 wt.-%, even more preferably 6 to 30 wt.-%, even more preferably 6 to 20 wt.-%, and most preferably 7 to 15 wt.-%. and / or - The at least one modified conjugated diene-based polymer has a vinyl content ranging from 10 to 80 wt.-%, preferably 15 to 65 wt.-%, more preferably 20 to 60 wt.-%, even more preferably 25 to 55 wt.-%, and most preferably 30 to 50 wt.-%.

5. The sulfur-crosslinkable rubber composition according to any one of claims 1 to 4, wherein, In the at least one modified conjugated diene-based polymer, the nitrogen-containing functional group comprises - An N-heterocyclic alkyl moiety having one, two, or three cyclic nitrogen atoms; Preferably, it is a six-membered ring; or - An amino hydrocarbon moiety containing a tertiary nitrogen atom.

6. The sulfur-crosslinkable rubber composition according to claim 5, wherein, The N-heterocyclic alkyl moiety having one, two, or three cyclic nitrogen atoms contains - Piperidine fraction, - Diazine moiety, The preferred fraction is piperazine. More preferably, the 1-methsilyl-piperazine moiety or the 1-methsilylalkyl-piperazine moiety, Even more preferred are the 1-(trialkylsilyl)piperazine moiety or the 1-(3-(dialkyl(tert-alkoxy)silyl)propyl)piperazine moiety. The most preferred moiety is either 1-(trimethylsilyl)piperazine or 1-(3-(dimethyl(tert-butoxy)silyl)propyl)piperazine; and / or - Triazine moiety, The preferred moiety is 1,3,5-triazine.

7. The sulfur-crosslinkable rubber composition according to claim 5, wherein, The amino hydrocarbon moiety containing tertiary nitrogen atoms contains - An N,N-(dialkyl)amino hydrocarbon moiety having one or more double bonds. The preferred reaction compound is a reaction compound of 3-(dimethylamino)propyllithium and isoprene; and / or - N,N-bis(silyl)aminoalkyl-silane moiety The preferred moiety is N,N-bis(trimethylsilyl)aminopropylmethyldiethoxysilane.

8. The sulfur-crosslinkable rubber composition according to any one of claims 1 to 7, wherein, In the at least one modified conjugated diene-based polymer, the sulfur-containing functional group is selected from the group consisting of: - Thionylpropane moiety; - Carbon disulfide portion; - Hydroxyl thiol moiety, Preferred olefin thiol moiety, The propylene mercaptan fraction is the preferred option; - Sulfide portion, The preferred aromatic sulfide portion, The preferred option is the phenyl vinyl sulfide moiety; - Thioester portion; - Dithioester moiety, The preferred aromatic disulfide fraction is... The cumyl dithiobenzoate moiety is the preferred option; - Thione moiety, The preferred aromatic thion fraction is... The most preferred moiety is the bis(dimethylamino)thiobenzophenone fraction. or Preferred branched aliphatic thion moiety, The di-tert-butylthione moiety is the preferred option; - Dithiane moiety, The preferred alkyl dithiane moiety is... The methyl-1,3-dithiane moiety is preferred; - Dithiopentane moiety; - Thiophene fraction; and / or - A dialkyltin (IV) disulfide moiety or a dialkylsilyl disulfide moiety, each comprising an alkoxysilyl group. The preferred moiety is dialkyltin(IV) bis(alkoxysilylalkyl sulfide).

9. The sulfur-crosslinkable rubber composition according to any one of claims 1 to 8, wherein, The at least one modified conjugated diene-based polymer has a sulfur content in the range of 50 to 800 ppm, preferably 65 to 675 ppm, more preferably 80 to 550 ppm, even more preferably 95 to 425 ppm, even more preferably 110 to 300 ppm, and most preferably 125 to 250 ppm based on the total weight of the polymer.

10. The sulfur-crosslinkable rubber composition according to any one of claims 1 to 9, wherein, The at least one modified conjugated diene-based polymer has a nitrogen content in the range of 25 to 500 ppm, preferably 50 to 420 ppm, based on the total weight of the polymer.

11. The sulfur-crosslinkable rubber composition according to any one of claims 1 to 10, wherein, The at least one modified conjugated diene-based polymer has a weight-average molecular weight M in the range of 50,000 to 2,000,000 g / mol, preferably 70,000 to 1,500,000 g / mol, more preferably 90,000 to 1,000,000 g / mol, even more preferably 110,000 to 750,000 g / mol, even more preferably 130,000 to 500,000 g / mol, and most preferably 130,000 to 300,000 g / mol. w .

12. The sulfur-crosslinkable rubber composition according to any one of claims 1 to 11, further comprising: (c) Unlike the diene-based rubber polymers of (b), which are preferably selected from the group consisting of: natural polyisoprene (NR), synthetic polyisoprene (IR), polybutadiene (BR; butadiene rubber), styrene-butadiene copolymer (SBR, styrene-butadiene rubber), butyl rubber (IIR) and halogenated butyl rubber.

13. A sulfur-vulcanized rubber composition, which can be obtained by sulfur-vulcanization of a sulfur-crosslinkable rubber composition according to any one of claims 1 to 12.

14. A rubber product comprising the sulfur-vulcanized rubber composition according to claim 13.

15. A tire, preferably a vehicle tire, most preferably a pneumatic vehicle tire, wherein at least a portion of the tire comprises the rubber product according to claim 14.

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