Natural rubber composition for pneumatic tires

Abstract

To provide a silica-filled natural rubber vulcanized product with improved properties. [Solution] A vulcanizable rubber composition is disclosed comprising rubber components including (a) natural rubber, (b) functionalized synthetic polyisoprene, and (c) optionally butadiene-based synthetic rubber, a silica filler, and a curing agent.

Description

[Technical Field]

[0001] Embodiments of the present invention relate to rubber compositions for pneumatic tires, and more particularly to polyisoprene-based rubber compounds. [Background technology]

[0002] Polyisoprene rubber, such as natural rubber, is often used in the manufacture of pneumatic tire components. Tire components, such as tire treads, containing relatively high levels of natural rubber typically exhibit good tensile properties, high tear strength, and impact and abrasion resistance. One or more of these advantageous properties are thought to stem from the fact that natural rubber undergoes strain-induced crystallization. As a result, natural rubber is advantageously used in relatively large quantities in components of heavy vehicle tires, such as truck tires, bus tires, subway tires, tractor trailer tires, aircraft tires, agricultural tires, earth mover tires, and other off-the-road (OTR) tires. [Overview of the project]

[0003] One or more embodiments of the present invention provide a vulcanizable rubber composition comprising a rubber component including (a) natural rubber, (b) functionalized synthetic polyisoprene, and (c) optionally butadiene-based synthetic rubber, a silica filler, and a curing agent. [Modes for carrying out the invention]

[0004] Embodiments of the present invention are based, at least in part, on the discovery of natural rubber-based silica-filled vulcanizable compositions useful for preparing vulcanizable rubber components having improved properties. In one or more embodiments, the natural rubber-based silica-filled vulcanizable composition comprises synthetic polyisoprene having silica-interacting functional groups. While silica reinforcements have proven useful in rubber components, particularly in tire treads, useful reinforcements require the use of synthetic polymers adapted to interact with silica. Natural rubber is not readily modified to react with silica, and therefore, natural rubber compositions are typically not reinforced with silica. Furthermore, it has been observed that the natural rubber phase separates from most butadiene-based synthetic rubbers often used with natural rubber in vulcanizable compositions. Thus, these natural rubber domains lack polymer-filler interactions in silica-filled formulations. Synthetic polyisoprene is miscible with natural rubber domains in these rubber formulations, and it has now been observed that synthetic polyisoprene having silica-interacting functional groups imparts polymer-filler interactions to these domains in silica-filled formulations. As a result, the present invention provides silica-filled natural rubber vulcanizable products having unexpectedly improved properties. These unexpected properties include not only those realized by polymer-silica interactions, but also those typically obtained from natural rubber, including at least one of favorable tensile strength, tear strength, abrasion resistance, and impact resistance. Accordingly, embodiments of the present invention relate to vulcanized materials that benefit from an overall balance of these properties, including treads for off-road radial tires.

[0005] Natural rubber-based vulcanizable composition As described above, the vulcanized products of the present invention are prepared from a natural rubber-based vulcanizable composition, which is sometimes simply called a vulcanizable composition. According to one or more embodiments, the natural rubber-based vulcanizable composition comprises a vulcanizable rubber component including (i) natural rubber, (ii) synthetic polyisoprene having silica-interacting functional groups, and (iii) optionally synthetic butadiene-based rubber. The vulcanizable composition also includes silica fillers and vulcanizing agents. Furthermore, the vulcanizable composition of the present invention may also include other components that may be included in a useful vulcanizable composition, for example, but not limited to, silica fillers and coupling agents for linking polymers, non-silica fillers, stearic acid, metal compounds, such as zinc oxide or derivative zinc oxide, processing oils and / or extender oils, resins, waxes, curing accelerators, scorch inhibitors, degradation inhibitors, antioxidants, and other rubber compounding additives known in the art.

[0006] Components of vulcanized rubber As described above, the vulcanizable rubber components include (i) natural rubber, (ii) synthetic polyisoprene having silica-interacting functional groups, and (iii) optionally synthetic butadiene-based rubber.

[0007] In one or more embodiments, the vulcanizable rubber component of a natural rubber-based vulcanizable composition contains more than 40% by weight of natural rubber, more than 50% by weight in other embodiments, and more than 55% by weight in other embodiments, based on the total weight of the vulcanizable rubber component. In these or other embodiments, the vulcanizable rubber component contains less than 90% by weight of natural rubber, less than 80% by weight in other embodiments, and less than 75% by weight in other embodiments, based on the total weight of the vulcanizable rubber component. In one or more embodiments, the vulcanizable rubber component contains about 40 to about 90% by weight of natural rubber, about 50 to about 80% by weight in other embodiments, and about 55 to about 75% by weight in other embodiments, based on the total weight of the vulcanizable rubber component.

[0008] In one or more embodiments, the vulcanizable rubber component comprises more than 10% by weight, more than 12% by weight in other embodiments, and more than 15% by weight in other embodiments, based on the total weight of the vulcanizable rubber component. In these or other embodiments, the vulcanizable rubber component comprises less than 40% by weight, less than 30% by weight in other embodiments, and less than 25% by weight in other embodiments, based on the total weight of the vulcanizable rubber component. In one or more embodiments, the vulcanizable rubber component comprises about 10 to about 40% by weight, about 12 to about 30% by weight in other embodiments, and about 15 to about 25% by weight in other embodiments, based on the total weight of the vulcanizable rubber component.

[0009] In one or more embodiments, the vulcanizable rubber component includes more than 5% by weight of synthetic butadiene rubber, more than 10% by weight in other embodiments, and more than 15% by weight in other embodiments, based on the total weight of the vulcanizable rubber component. In these or other embodiments, the vulcanizable rubber component includes less than 40% by weight of synthetic butadiene rubber, less than 35% by weight in other embodiments, and less than 30% by weight in other embodiments, based on the total weight of the vulcanizable rubber component. In one or more embodiments, the vulcanizable rubber component includes about 0 to about 40% by weight of synthetic butadiene rubber, about 10 to about 35% by weight in other embodiments, and about 15 to about 30% by weight in other embodiments, based on the total weight of the vulcanizable rubber component.

[0010] Natural rubber As those skilled in the art will understand, natural rubber contains naturally occurring polyisoprene, which may also be called natural polyisoprene or natural cis-1,4-polyisoprene. This polymer is found in various trees, shrubs and plants, such as the Para rubber tree (i.e., the Amazon rubber tree), Castella elastica (i.e., the Panama rubber tree), various Landophia vines (L. kirkii, L. heudelotis, and L. owariensis), various dandelions (i.e., plants of the genus Taraxacum), and Parthenium argentatum (guayule shrub).

[0011] Synthetic functionalized polyisoprene In one or more embodiments, synthetic polyisoprenes having silica-interacting functional groups are sometimes called functionalized synthetic polyisoprenes or simply functionalized IRs, and include polymers obtained by the synthetic polymerization of isoprene monomers. In one or more embodiments, the polymers are synthesized by using anionic polymerization techniques. As will be described in more detail below, these techniques produce reactive polymers that can be terminally functionalized by reacting a reactive polymer with a functionalizing agent, thereby imparting silica-reactive or interacting groups to the polymer.

[0012] The preparation of polymers using anionic polymerization techniques is generally known. Key features of the mechanisms of anionic polymerization are described in books (e.g., Hsieh, HL; J. Quirk, RPA Anionic Polymerization: Principles and Practical Applications; Marcel Dekker: New York, 1996) and review articles (e.g., Hadjichristidis, N. Pitsikalis, M. Pispas, S. Iatrou, H. Chem. Rev. 2001, 101(12), 3747-3792). Anionic initiators can advantageously produce polymers (e.g., living polymers) with reactive polymer chain ends that can react with additional monomers for further chain growth or react with specific functionalizing agents to give functionalized polymers before quenching. Polymers with reactive polymer chain ends are sometimes simply referred to as reactive polymers. As those skilled in the art will understand, these reactive polymers include reactive chain ends, which are considered to be ionic, and a reaction occurs at these reactive chain ends between the functionalizing agent and the reactive chain ends of the polymer, thereby conferring functionality or functional groups to the polymer chain ends, or coupling multiple polymers together.

[0013] The implementation of the present invention is not limited by the selection of any particular anionic initiator. Exemplary anionic initiators include organolithium compounds. In one or more embodiments, the organolithium compound may contain a heteroatom. In these or other embodiments, the organolithium compound may contain one or more heterocyclic groups. Types of organolithium compounds include alkyllithium compounds, aryllithium compounds, and cycloalkyllithium compounds. Specific examples of organolithium compounds include ethyllithium, n-propyllithium, isopropyllithium, n-butyllithium, sec-butyllithium, t-butyllithium, n-amyllithium, isoamyllithium, and phenyllithium. Further examples of anionic initiators include organosodium compounds, such as phenylsodium and 2,4,6-trimethylphenylsodium.

[0014] Anionic polymerization may be carried out in polar solvents, nonpolar solvents, or mixtures thereof. In one or more embodiments, a solvent may be used as a support to dissolve or suspend the initiator to facilitate delivery of the initiator to the polymerization system.

[0015] In one or more embodiments, preferred solvents include organic compounds that are neither polymerized nor incorporated into the propagating polymer chain during polymerization of monomers in the presence of the catalyst. In one or more embodiments, these organic species are liquid at ambient temperature and pressure. In one or more embodiments, these organic solvents are inert to the catalyst. Exemplary organic solvents include hydrocarbons with low or relatively low boiling points, such as aromatic hydrocarbons, aliphatic hydrocarbons, and alicyclic hydrocarbons. Non-limiting examples of aromatic hydrocarbons include benzene, toluene, xylene, ethylbenzene, diethylbenzene, and mesitylene. Non-limiting examples of aliphatic hydrocarbons include n-pentane, n-hexane, n-heptane, n-octane, n-nonane, n-decane, isopentane, isohexane, isopentane, isooctane, 2,2-dimethylbutane, petroleum ether, kerosene, and petroleum spirits. Non-limiting examples of alicyclic hydrocarbons include cyclopentane, cyclohexane, methylcyclopentane, and methylcyclohexane. Mixtures of the above hydrocarbons may also be used. Low-boiling hydrocarbon solvents are typically separated from the polymer when polymerization is complete. Other examples of organic solvents include high molecular weight, high-boiling hydrocarbons such as paraffinic oils, aromatic oils, or other hydrocarbon oils commonly used in oil-expandable polymers. Because these hydrocarbons are non-volatile, they typically do not need to be separated and remain incorporated into the polymer.

[0016] Anionic polymerization may be carried out in the presence of a catalyst modifier (which may also be referred to as a polar coordinator) or a vinyl modifier. As will be understood by those skilled in the art, these compounds modify the vinyl content of the mer units derived from dienes. Compounds useful as catalyst modifiers include those having an oxygen or nitrogen heteroatom and a non-bonding electron pair. Examples include linear and cyclic oligomeric oxolanyl alkanes; dialkyl ethers of mono- and oligoalkylene glycols (also known as glyme ethers); "crown" ethers; tertiary amines; linear THF oligomers; and the like. Linear and cyclic oligomeric oxolanyl alkanes are described in U.S. Patent Nos. 4,429,091 and 9,868,795, which are incorporated herein by reference. Specific examples of compounds useful as modifiers include the following. Specific examples of compounds useful as randomizers include 2,2-bis(2-oxolanyl)propane (also known as 2,2-ditetrahydrofurylpropane), meso-2,2-ditetrahydrofurylpropane, DL-2,2,-ditetrahydrofurylpropane, and mixtures thereof, 1,2-dimethoxyethane, N,N,N',N'-tetramethylethylenediamine (TMEDA), tetrahydrofuran (THF), 1,2-dipiperidylethane, dipiperidylmethane, hexamethylphosphoramide, N,N'-dimethylpiperazine, diazabicyclooctane, dimethyl ether, diethyl ether, tri-n-butylamine, and mixtures thereof.

[0017] The amount of modifier to be used may depend on various factors (e.g., the desired polymer microstructure, the polymerization temperature, and the nature of the specific modifier used). In one or more embodiments, the amount of modifier used may be in the range of 0.01 to 100 millimoles of modifier per millimole of anionic initiator, or in other embodiments, from about 0.02 to about 10 millimoles, or from about 0.03 to about 0.1 millimole.

[0018] Anionic initiators and modifiers can be introduced into the polymerization system by various methods. In one or more embodiments, the anionic initiator and modifier can be added separately to the monomers to be polymerized, either stepwise or simultaneously.

[0019] As will be appreciated by those skilled in the art, the polymerization of isoprene monomers in the presence of an effective amount of an initiator produces a reactive polyisoprene polymer. The introduction of the initiator, isoprene monomer, and solvent forms a polymerization mixture in which the reactive polymer is formed. When polymerized in a solvent, a polymerization mixture is produced in which the polymer product is dissolved or suspended in the solvent. This polymerization mixture may also be referred to as a polymer cement.

[0020] The amount of initiator used may depend on the interaction of various factors (e.g., the type of initiator used, the purity of the components, the polymerization temperature, the desired polymerization rate and conversion, the desired molecular weight, and many other factors). In one or more embodiments, the amount of initiator used can be expressed as millimoles of initiator per weight of monomer. In one or more embodiments, the initiator loading can vary from about 0.05 to about 50 millimoles of initiator per 100 grams of monomer, in other embodiments from about 0.1 to about 25 millimoles, in still other embodiments from about 0.2 to about 2.5 millimoles, and in other embodiments from about 0.4 to about 0.7 millimoles.

[0021] In one or more embodiments, the polymerization may be carried out in any conventional polymerization vessel known in the art. For example, the polymerization can be carried out in a conventional stirred tank reactor. In one or more embodiments, all of the components used in the polymerization can be mixed in a single vessel (e.g., a conventional stirred tank reactor), and all steps of the polymerization process can be carried out in this vessel. In other embodiments, two or more components can be pre-combined in one vessel and then transferred to another vessel where the polymerization of the monomer (or at least most of it) can be carried out. Since various embodiments of the present invention include the use of multiple reactors or reaction zones, the vessel in which the polymerization is carried out (e.g., a tank reactor) may sometimes be referred to as the first vessel or the first reaction zone.

[0022] Polymerization can be carried out as a batch process, a continuous process, or a semi-continuous process. In a semi-continuous process, monomers are intermittently packed as needed to replace already polymerized monomers. In one or more embodiments, the conditions under which polymerization proceeds can be controlled to maintain the temperature of the polymerization mixture in the range of about -10°C to about 200°C, in other embodiments about 0°C to about 150°C, and in other embodiments about 20°C to about 110°C. In one or more embodiments, the heat of polymerization may be removed by external cooling with a thermally controlled reactor jacket, internal cooling by vaporization and condensation of monomers using a reflux condenser connected to the reactor, or a combination of the two methods. The conditions may also be controlled to carry out polymerization under pressures of about 0.1 atmospheres to 50 atmospheres, in other embodiments about 0.5 atmospheres to about 20 atmospheres, and in other embodiments about 1 atmosphere to about 10 atmospheres. In one or more embodiments, the pressures under which polymerization can occur include pressures under which the majority of monomers are reliably in the liquid phase. In these or other embodiments, the polymerization mixture may be maintained under anaerobic conditions.

[0023] Properties of base polyisoprene In one or more embodiments, the base polyisoprene polymer, which is the polymer before functionalization, may be characterized as follows:

[0024] In one or more embodiments, the base polyisoprene may be characterized by a number-average molecular weight (Mn), a weight-average molecular weight (Mw), a peak molecular weight (Mp), and a molecular weight distribution (Mw / Mn), which may be called polydispersity. As will be understood by those skilled in the art, Mn and Mw can be determined by using gel permeation chromatography (GPC) with appropriate calibration standards. For the purposes of this specification, GPC measurements are performed using polystyrene standards and THF as the solvent. Also, unless otherwise specified, since functionalization can result in polymer coupling or dimerization by condensation, for example, which has the effect of doubling the weight of the polymer, molecular weight refers to the weight of the polymer before functionalization (which may be called the base polymer). Since the weight of the functional units does not otherwise have a sensible effect on the polymer molecular weight, the term weight of functionalized synthetic polyisoprene is therefore considered to be the same as the base polymer without coupling or dimerization, unless otherwise specified.

[0025] In one or more embodiments, the base synthetic polyisoprene may be characterized by a peak molecular weight (Mp) greater than 100 kg / mol, greater than 150 kg / mol in other embodiments, and greater than 200 kg / mol in other embodiments. In these or other embodiments, the base synthetic polyisoprene may be characterized by an Mp less than 700 kg / mol, less than 600 kg / mol in other embodiments, less than 500 kg / mol in other embodiments, less than 450 kg / mol in other embodiments, less than 400 kg / mol in other embodiments, less than 370 kg / mol in other embodiments, and less than 350 kg / mol in other embodiments. In one or more embodiments, the base synthetic polyisoprene may have an Mp of about 100 to about 700 kg / mol, about 150 to about 450 kg / mol in other embodiments, and about 200 to about 350 kg / mol in other embodiments.

[0026] In one or more embodiments, the base polyisoprene may be characterized by a number-average molecular weight (Mn) greater than 100 kg / mol, greater than 150 kg / mol in other embodiments, and greater than 200 kg / mol in other embodiments. In these or other embodiments, the base polyisoprene may be characterized by an Mn of less than 700 kg / mol, less than 600 kg / mol in other embodiments, less than 500 kg / mol in other embodiments, less than 450 kg / mol in other embodiments, and less than 400 kg / mol in other embodiments. In one or more embodiments, the base polyisoprene may have an Mn of about 100 to about 700 kg / mol, about 150 to about 450 kg / mol in other embodiments, about 100 to about 350 kg / mol in other embodiments, and about 200 to about 400 kg / mol in other embodiments.

[0027] In one or more embodiments, the base polyisoprene may be characterized by a weight-average molecular weight (Mw) greater than 110 kg / mol, greater than 220 kg / mol in other embodiments, and greater than 330 kg / mol in other embodiments. In these or other embodiments, the base polyisoprene may be characterized by an Mw of less than 900 kg / mol, less than 800 kg / mol in other embodiments, less than 700 kg / mol in other embodiments, less than 600 kg / mol in other embodiments, and less than about 550 kg / mol in other embodiments. In one or more embodiments, the base synthetic polyisoprene may have an Mw of about 110 to about 900 kg / mol, about 220 to about 700 kg / mol in other embodiments, and about 330 to about 550 kg / mol in other embodiments.

[0028] In one or more embodiments, the base polyisoprene can be characterized by its vinyl content, which can be described as the number of unsaturated units in the 3,4 microstructure relative to the total unsaturation in the polymer chain. As will be understood by those skilled in the art, the vinyl content can be determined by NMR analysis (e.g., using CDCl3 as a solvent). In one or more embodiments, the base polyisoprene contains more than 2%, more than 3% in other embodiments, and more than 5% in other embodiments. In these or other embodiments, the base polyisoprene contains less than 45%, less than 20% in other embodiments, and less than 15% in other embodiments. In one or more embodiments, the base polyisoprene contains about 2 to about 45%, about 3 to about 30% in other embodiments, and about 4 to about 20% in other embodiments. In one or more embodiments, the remainder of the polymer units are 1,4-cis or 1,4-trans microstructures, and the ratio of 1,4-cis to 1,4-trans is in the range of about 1:1 to about 3:1, or about 1:3 to about 2.5:1 in other embodiments.

[0029] In one or more embodiments, the base polyisoprene may be characterized by its 1,4-cis and 1,4-trans content. As will be understood by those skilled in the art, the microstructure (e.g., 1,4-cis and 1,4-trans content) can be determined by NMR analysis (e.g., using CDCl3 as the solvent). In one or more embodiments, the base polyisoprene contains more than 40% of its units in the cis-1,4 microstructure, more than 55% in other embodiments, and more than 65% in other embodiments. In these or other embodiments, the base polyisoprene contains less than 90% of its units in the cis-1,4 microstructure, less than 80% in other embodiments, and less than 70% in other embodiments. In one or more embodiments, the base polyisoprene contains about 40 to about 90% of its units in the cis-1,4 microstructure, about 45 to about 85% in other embodiments, and about 50 to about 75% in other embodiments. In these or other embodiments, the base polyisoprene comprises more than 5% of its units in the trans-1,4 microstructure, more than 10% in other embodiments, and more than 15% in other embodiments. In these or other embodiments, the base polyisoprene comprises less than 50% of its units in the trans-1,4 microstructure, less than 40% in other embodiments, and less than 30% in other embodiments. In one or more embodiments, the base polyisoprene comprises about 5 to about 50% of its units in the cis-1,4 microstructure, about 10 to about 40% in other embodiments, and about 15 to about 35% in other embodiments.

[0030] Polyisoprene functionalization As shown above, following polymerization, the reactive polyisoprene polymer is terminally functionalized, which may also be referred to as terminally modified, or simply functionalized or modified. That is, the reactive ends of the polymer react with a compound that may be called a functionalizing agent or modifier, which confers silica-interacting groups to the polymer ends. The polymer chain ends are thought to react with the functionalizing agent or modifier to provide functionalizing agent residues to the ends of the polymer chains. Thus, the reaction between the polymer and the functionalizing agent produces a polymer composition comprising one or more polymer chains containing terminal groups derived from the functionalizing agent or modifier. In one or more embodiments, more than 50 mol% of the polymer chains in the polymer composition, more than 70 mol% in other embodiments, and more than 90 mol% in other embodiments are reactive and can react with the functionalizing agent. In one or more embodiments, about 50 to about 100 mol% of the polymer chains in the polymer composition, about 60 to about 97 mol% in other embodiments, and about 70 to about 95 mol% in other embodiments contain reactive ends that can react with the functionalizing agent.

[0031] The implementation of the present invention is not limited by any particular choice of functionalizing agent, insofar as the functionalization imparts silica-interacting functional groups to the polymer chain ends. In one or more embodiments, the functionalizing agent imparts hydrolyzable groups to the polymer chain ends. In these or other embodiments, the functionalizing agent is a silicon-containing functionalizing agent.

[0032] In one or more embodiments, a useful silicon-containing functionalizing agent (which may also be called a siloxane inhibitor, a hydrocarbyloxysilane functionalizing agent, or a hydrocarbyloxysilane inhibitor) may be defined by the following formula: (R 1 ) 4-z-y Si(R 2 )y(OR 2 ) z In the formula, R 1 is a halogen atom or a monovalent organic group, and each R 2 is a monovalent organic group, z is an integer from 1 to 4, and y is an integer from 0 to 2. In one embodiment, the halogen atom is chlorine.

[0033] In one or more embodiments, the monovalent organic group is a hydrocarbyl group, including, but not limited to, alkyl groups, cycloalkyl groups, alkenyl groups, cycloalkenyl groups, aryl groups, allyl groups, aralkyl groups, alkaryl groups, or alkynyl groups. Hydrocarbyl groups also include substituted hydrocarbyl groups. A substituted hydrocarbyl group refers to a hydrocarbyl group in which one or more hydrogen atoms are replaced by substituents (e.g., hydrocarbyl groups). In one or more embodiments, these groups may contain one (or the minimum number of carbon atoms appropriate to form the group) to about 20 carbon atoms. These groups may or may not contain heteroatoms. Preferred heteroatoms include, but are not limited to, nitrogen, boron, oxygen, silicon, sulfur, tin, and phosphorus. In one or more embodiments, the cycloalkyl, cycloalkenyl, and aryl groups are nonheterocyclic groups. In these or other embodiments, the substituents forming the substituted hydrocarbyl group are nonheterocyclic groups.

[0034] Suitable examples of siloxane end-terminating agents include tetraalkoxysilanes, alkylalkoxysilanes, arylalkoxysilanes, alkenylalkoxysilanes, and haloalkoxysilanes.

[0035] Examples of tetraalkoxysilane compounds include tetramethyl orthosilicate, tetraethyl orthosilicate, tetrapropyl orthosilicate, tetrabutyl orthosilicate, tetra(2-ethylhexyl) orthosilicate, tetraphenyl orthosilicate, and tetratolyloxysilane.

[0036] Examples of alkylalkoxysilanes include methyltrimethoxysilane, methyltriethoxysilane, methyltri-n-propoxysilane, methyltri-n-butoxysilane, methyltriphenoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltri-n-propoxysilane, ethyltritri-n-butoxysilane, ethyltriphenoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyldi-n-propoxysilane, dimethyldi-n-butoxysilane, dimethyldiphenoxysilane, diethyldimethoxysilane, and diphenyldimethoxysilane.

[0037] Examples of arylalkoxysilane compounds include phenyltrimethoxysilane, phenyltriethoxysilane, phenyltri-n-propoxysilane, phenyltri-n-butoxysilane, and phenyltriphenoxysilane.

[0038] Examples of alkenylalkoxysilane compounds include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri-n-propoxysilane, vinyltri-n-butoxysilane, vinyltriphenoxysilane, allyltrimethoxysilane, octenyltrimethoxysilane, and divinyldimethoxysilane.

[0039] Examples of haloalkoxysilane compounds include trimethoxy chlorosilane, triethoxy chlorosilane, tri-n-propoxy chlorosilane, tri-n-butoxy chlorosilane, triphenoxy chlorosilane, dimethoxy dichlorosilane, diethoxy dichlorosilane, di-n-propoxy dichlorosilane, diphenoxy dichlorosilane, methoxy trichlorosilane, ethoxy trichlorosilane, n-propoxy trichlorosilane, phenoxy trichlorosilane, trimethoxy bromosilane, triethoxy bromosilane, tri-n-propoxy bromosilane, triphenoxy bromosilane, dimethoxy dibromosilane, diethoxy dibromosilane, di-n-propoxy dibromosilane, diphenoxy dibromosilane, methoxy tribromosilane, ethoxy tribromosilane, n-propoxy tribromosilane, phenoxy tribromosilane, trimethoxy iodosilane, triethoxy iodosilane, tri-n-propoxy iodosilane, triphenoxy iodosilane, dimethoxy diiodosilane, di-n-propoxy diiodosilane, diphenoxy diiodosilane, methoxy triiodosilane, ethoxy triiodosilane, n-propoxy triiodosilane, and phenoxy triiodosilane.

[0040] Techniques for preparing functionalized polymers by using hydrocarbyloxysilane compounds are described in U.S. Patent Nos. 3,244,664, 6,008,295, 6,228,908, and 4,185,042, which are incorporated herein by reference.

[0041] In one or more embodiments, examples of hydrocarbyloxysilane functionalizing agents include imino-containing hydrocarbyloxysilanes that can be defined by the following formula:

[0042]

Chemical formula

[0043] In one or more embodiments, the divalent organic group is a hydrocarbilene group, such as alkylene, cycloalkylene, alkenylene, cycloalkenylene, alkylylene, cycloalkenylene, or arylene group, but is not limited to these. The hydrocarbilene group includes a substituted hydrocarbile group, which refers to a hydrocarbilene group in which one or more hydrogen atoms are replaced by a substituent (e.g., a hydrocarbyl group). In one or more embodiments, these groups may contain one (or the minimum number of carbon atoms appropriate to form the group) to about 20 carbon atoms. These groups may or may not contain heteroatoms. Preferred heteroatoms include, but are not limited to, nitrogen, boron, oxygen, silicon, sulfur, tin, and phosphorus. In one or more embodiments, the cycloalkylene, cycloalkenylene, and arylene groups are nonheterocyclic groups. In these or other embodiments, the substituents forming the substituted hydrocarbilene group are nonheterocyclic groups.

[0044] Examples of these imino-containing hydrocarbyloxysilane compounds include, but are not limited to, triethoxy compounds such as N-(1,3-dimethylbutylidene)-3-(triethoxysilyl)-1-propanamine, N-(1-methylethylidene)-3-(triethoxysilyl)-1-propanamine, N-ethylidene-3-(triethoxysilyl)-1-propanamine, N-(1-methylpropyridene)-3-(triethoxysilyl)-1-propanamine, N-(4-N,N-dimethylaminobenzylidene)-3-(triethoxysilyl)-1-propanamine, and N-(cyclohexylidene)-3-(triethoxysilyl)-1-propanamine. Other examples include, but are not limited to, trimethoxy compounds such as N-(1,3-dimethylbutylidene)-3-(trimethoxysilyl)-1-propanamine, N-(1-methylethylidene)-3-(trimethoxysilyl)-1-propanamine, N-ethylidene-3-(trimethoxysilyl)-1-propanamine, N-(1-methylpropyridene)-3-(trimethoxysilyl)-1-propanamine, N-(4-N,N-dimethylaminobenzylidene)-3-(trimethoxysilyl)-1-propanamine, and N-(cyclohexylidene)-3-(trimethoxysilyl)-1-propanamine. Other examples include, but are not limited to, methyldiethoxy compounds such as N-(1,3-dimethylbutylidene)-3-(methyldiethoxysilyl)-1-propanamine, N-(1-methylethylidene)-3-(methyldiethoxysilyl)-1-propanamine, N-ethylidene-3-(methyldiethoxysilyl)-1-propanamine, N-(1-methylpropyridene)-3-(methyldiethoxysilyl)-1-propanamine, N-(4-N,N-dimethylaminobenzylidene)-3-(methyldiethoxysilyl)-1-propanamine, and N-(cyclohexylidene)-3-(methyldiethoxysilyl)-1-propanamine.Other examples include, but are not limited to, ethyldimethoxy compounds such as N-(1,3-dimethylbutylidene)-3-(ethyldimethoxysilyl)-1-propanamine, N-(1-methylethylidene)-3-(ethyldimethoxysilyl)-1-propanamine, N-ethylidene-3-(ethyldimethoxysilyl)-1-propanamine, N-(1-methylpropyridene)-3-(ethyldimethoxysilyl)-1-propanamine, N-(4-N,N-dimethylaminobenzylidene)-3-(ethyldimethoxysilyl)-1-propanamine, and N-(cyclohexylidene)-3-(ethyldimethoxysilyl)-1-propanamine.

[0045] Techniques for preparing functionalized polymers using imino-containing hydrocarbyloxy compounds are disclosed in U.S. Patent Applications Publications 2005 / 0009979, 2010 / 0113683, and 2011 / 0092633, which are incorporated herein by reference.

[0046] In one or more embodiments, the hydrocarbyloxysilane functionalizing agent is a hydrocarbyloxysilane defined by the following formula:

[0047] [ka] (In the formula, R 4 is a divalent organic group, R 5 and R 6 Each of these is independently a hydrocarbyloxy group or a hydrocarbyl group, and R 5 (where A is a monovalent organic group, and A is selected from the group consisting of carboxylic acid esters, cyclic tertiary amines, acyclic tertiary amines, pyridine, silazane, isocyanate, cyano, carboxylic acid anhydride, epoxy, and sulfide groups).

[0048] Examples of hydrocarbyloxysilane compounds containing a carboxylic acid ester group include, but are not limited to, 3-methacryloyloxypropyltriethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropylmethyldiethoxysilane, and 3-methacryloyloxypropyltriisopropoxysilane.

[0049] Examples of hydrocarbyloxysilane compounds containing a cyclic tertiary amine group include 3-(1-hexamethyleneimino)propyltriethoxysilane, 3-(1-hexamethyleneimino)propyltrimethoxysilane, (1-hexamethyleneimino)methyltriethoxysilane, (1-hexamethyleneimino)methyltrimethoxysilane, 2-(1-hexamethyleneimino)ethyltriethoxysilane, and 3-(1-hexamethyleneimino)ethyltrimeth Examples include, but are not limited to, xysilane, 3-(1-pyrrolidinyl)propyltrimethoxysilane, 3-(1-pyrrolidinyl)propyltriethoxysilane, 3-(1-heptamethyleneimino)propyltriethoxysilane, 3-(1-dodecamethyleneimino)propyltriethoxysilane, 3-(1-hexamethyleneimino)propyldiethoxymethylsilane, and 3-[10-(triethoxysilyl)decyl]-4-oxazoline.

[0050] Examples of hydrocarbyloxysilane compounds containing an acyclic tertiary amine group include, but are not limited to, 3-dimethylaminopropyltriethoxysilane, 3-dimethylaminopropyltrimethoxysilane, 3-diethylaminopropyltrimethoxysilane, 3-diethylaminopropyltriethoxysilane, 2-dimethylaminoethyltrimethoxysilane, 2-dimethylaminoethyltrimethoxysilane, 3-dimethylaminopropyldiethoxymethylsilane, 3-diethylaminopropyldiethoxymethylsilane, 3-dimethylaminopropyldimethoxymethylsilane, 3-dimethylaminopropyldimethoxymethylsilane, and 3-dibutylaminopropyltriethoxysilane.

[0051] Examples of hydrocarbyloxysilane compounds containing a pyridine group include, but are not limited to, 2-trimethoxysilylethylpyridine.

[0052] Examples of hydrocarbyloxysilane compounds containing a silazane group include, but are not limited to, N,N-bis(trimethylsilyl)aminopropylmethyldimethoxysilane, 1-trimethylsilyl-2,2-dimethoxy-1-aza-2-silacyclopentane, N,N-bis(trimethylsilyl)aminopropyltrimethoxysilane, N,N-bis(trimethylsilyl)aminopropyltriethoxysilane, N,N-bis(trimethylsilyl)aminopropylmethyldiethoxysilane, N,N-bis(trimethylsilyl)aminoethyltrimethoxysilane, N,N-bis(trimethylsilyl)aminoethyltriethoxysilane, N,N-bis(trimethylsilyl)aminoethylmethyldimethoxysilane, and N,N-bis(trimethylsilyl)aminoethylmethyldiethoxysilane.

[0053] Examples of hydrocarbyloxysilane compounds containing an isocyanato group include, but are not limited to, 3-isocyanatopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-isocyanatopropylmethyldiethoxysilane, and 3-isocyanatopropyltriisopropoxysilane.

[0054] Examples of hydrocarbyloxysilane compounds containing a cyano group include, but are not limited to, 2-cyanoethylpropyltriethoxysilane.

[0055] Examples of hydrocarbyloxysilane compounds containing a carboxylic acid anhydride group include, but are not limited to, 3-trimethoxysilylpropyl succinic anhydride, 3-triethoxysilylpropyl succinic anhydride, and 3-methyldiethoxysilylpropyl succinic anhydride.

[0056] Examples of hydrocarbyloxysilane compounds containing epoxy groups include, but are not limited to, 2-glycidoxyethyltrimethoxysilane, 2-glycidoxyethyltriethoxysilane, (2-glycidoxyethyl)methyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, (3-glycidoxypropyl)-methyldimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, and 2-(3,4-epoxycyclohexyl)ethyl(methyl)dimethoxysilane.

[0057] In one or more embodiments, the amount of functionalizing agent used to prepare the synthetic functionalized polyisoprene polymer is best expressed in terms of the equivalent amount of lithium or metal cation associated with the initiator. For example, the number of moles of functionalizing agent per mole of lithium may be about 0.1 to about 10 in other embodiments, about 0.2 to about 2 in other embodiments, about 0.3 to about 3 in other embodiments, about 0.6 to about 1.5 in other embodiments, about 0.7 to about 1.3 in other embodiments, about 0.8 to about 1.1 in other embodiments, and about 0.9 to about 1.0 in other embodiments. For the purposes of this explanation, the reaction between the functionalizing agent and the reactive polymer is considered to be substantially quantitative.

[0058] In one or more embodiments, the amount of functionalizing agent used may be expressed in reference to the amount of polymer being functionalized. In one or more embodiments, the degree of functionalization is at least 50%, in other embodiments at least 60%, and in other embodiments at least 70%, based on the total number of reactive polymer molecules treated with the functionalizing agent. In these or other embodiments, the desired degree of functionalization is about 50 to about 100%, in other embodiments about 60 to about 95%, and in other embodiments about 70 to about 90%, based on the total number of reactive polymer molecules treated with the functionalizing agent.

[0059] In one or more embodiments, the reaction between the functionalizing agent and the reactive polymer may occur at temperatures ranging from about 10°C to about 150°C, and in other embodiments, from about 20°C to about 100°C. The time required for the reaction between the functionalizing agent and the reactive polymer to be completed depends on various factors, including the type and amount of catalyst or initiator used in the preparation of the reactive polymer, the type and amount of functionalizing agent, and the temperature at which the functionalization reaction takes place. In one or more embodiments, the reaction between the functionalizing agent and the reactive polymer may take place for about 10 to 60 minutes.

[0060] Post-functionalization In one or more embodiments, a quencher may be added to the polymerization mixture to deactivate any remaining reactive polymer chains and / or initiator residues after bonding and / or functionalization has been achieved or completed. In one or more embodiments, the addition of a quencher is optional, and therefore, in one or more embodiments, a quencher is not introduced into the polymerization mixture. Examples of quenchers include, but are not limited to, protic compounds, which include alcohols, carboxylic acids, inorganic acids, water, or mixtures thereof. Antioxidants, such as 2,6-di-tert-butyl-4-methylphenol, may be added together with, before, or after the addition of the quencher. The amount of antioxidant used may range from 0.2% to 1% by weight relative to the weight of the polymer product.

[0061] In one or more embodiments, polymer products can be recovered from the polymerization mixture by using any conventional desolvation and drying procedures known in the art. For example, polymer recovery can be performed by vapor desolvation of the polymer cement, followed by drying the resulting polymer crumb in a hot air tunnel. Alternatively, polymer recovery may be performed by directly drying the polymer cement on a drum dryer. The content of volatile substances in the dried polymer may be less than 1% by weight of the polymer, and less than 0.5% by weight in other embodiments. In one or more embodiments, after the formation of the polymer, processing aids and other optional additives such as oils may be added to the polymer cement. The polymer and other optional components may then be separated from the solvent and optionally dried. Conventional desolvation and drying procedures may be used. In one embodiment, the polymer can be separated from the solvent by vapor desolvation or hot water coagulation of the solvent, followed by filtration. The residual solvent can be removed by using conventional drying techniques such as oven drying or drum drying. Alternatively, the cement may be directly drum dried.

[0062] In one or more embodiments, a condensation accelerator may be added to the polymerization mixture after the introduction of a functionalizing agent to the reactive polymer, optionally after the addition of a quenching agent and / or antioxidant, and optionally after the recovery or separation of the functionalized polymer. Useful condensation accelerators include tin and / or titanium carboxylates and tin and / or titanium alkoxides. One specific example is titanium 2-ethylhexyl oxide. Useful condensation catalysts and their uses are disclosed in U.S. Patent Application Publication 2005 / 0159554(A1), which is incorporated herein by reference.

[0063] In one or more embodiments, after the reaction between the reactive polymer and the functionalizing agent is achieved or completed, further reactions with the functionalized polymer may be carried out optionally after the addition of a quenching agent and / or a condensation catalyst, and optionally after the recovery or separation of the functionalized polymer. For example, the functionalized polymer product may be treated in the presence of an alcohol, optionally a suitable catalyst, which is thought to result in the formation of hydrocarbyloxy groups instead of hydroxyl or halogen atoms that may be associated with the functional groups of the polymer. In these or other embodiments, the functionalized polymers resulting from the implementation of the present invention may be exposed to or treated with water, optionally in the presence of a catalyst, to cleave or substitute any hydrolyzable protecting groups that may be present or associated with the functional groups of the polymer. Strong acid catalysts, such as those described herein, may be used for this purpose.

[0064] Functionalized synthetic polyisoprenes can be characterized by their coupling rate, which those skilled in the art will understand can be determined by GPC analysis. In one or more embodiments, functionalized synthetic polyisoprenes can be characterized by a coupling rate greater than 50%, in other embodiments greater than 60%, and in other embodiments greater than 70%. In these or other embodiments, functionalized synthetic polyisoprenes can be characterized by a coupling rate less than 90%, in other embodiments less than 85%, and in other embodiments less than 80%. In one or more embodiments, functionalized synthetic polyisoprenes may be coupled to about 50-90%, in other embodiments about 55-85%, and in other embodiments about 60-75%.

[0065] Functionalized synthetic polyisoprenes can be characterized by their Mooney viscosity (ML 1+4 @ 100°C). In one or more embodiments, functionalized synthetic polyisoprenes may be characterized by a Mooney viscosity (ML 1+4 @ 100°C) greater than 45, greater than 50 in other embodiments, and greater than 55 in other embodiments. In these or other embodiments, functionalized synthetic polyisoprenes may be characterized by a Mooney viscosity (ML 1+4 @ 100°C) less than 100, less than 90 in other embodiments, and less than 85 in other embodiments. In one or more embodiments, functionalized synthetic polyisoprenes may be characterized by a Mooney viscosity (ML 1+4 @ 100°C) of about 45 to about 100, about 50 to about 90 in other embodiments, and about 55 to about 85 in other embodiments.

[0066] Synthetic butadiene rubber In one or more embodiments, the synthetic butadiene rubber includes polymers obtained by the synthetic polymerization of 1,3-butadiene, optionally by copolymerizing the 1,3-butadiene monomer with other conjugated diene monomers (e.g., isoprene), vinyl-substituted aromatic monomers (e.g., styrene), or other copolymerizable monomers such as ethylene or one or more α-olefins.

[0067] Examples of synthetic butadiene polymers include, for example, poly(butadiene), poly(styrene-co-butadiene), poly(butadiene-co-isoprene), and poly(styrene-co-isoprene-co-butadiene). In one or more embodiments, poly(butadiene) may include high cis-1,4-poly(butadiene), which generally has a cis content of more than 80 mol%, more than 90 mol%, and more than 95 mol% in the cis-1,4-microstructure. In other embodiments, such as when poly(butadiene) is synthesized by anionic technology, poly(butadiene) may be characterized by a moderate cis content and a relatively low vinyl content. In one or more embodiments, moderate-cis, low-vinyl poly(butadiene) may have a cis content of about 40 to about 80 mol%, more than 45 to about 70 mol%, and more than 50 to about 60 mol%, in the cis-1,4-microstructure. In these or other embodiments, the medium-cis, low-vinyl poly(butadiene) may be characterized by a vinyl content of less than 20 mol%, less than 18 mol% in other embodiments, and less than 15 mol% in other embodiments.

[0068] In one or more embodiments, the synthetic butadiene polymers are generally of the type of polymer typically used in the construction of tire components. For example, these polymers typically have a base number-average molecular weight (i.e., before coupling) greater than 90 kg / mol, greater than 120 kg / mol in other embodiments, and greater than 150 kg / mol in other embodiments.

[0069] In one or more embodiments, butadiene polymers are functionalized. As used herein, a functionalized polymer includes a polymer modified (i.e., functionalized) with a functionalizing compound that adds or imparts heteroatoms to polymer chains (e.g., chain ends). In certain embodiments, these functionalizers impart functional groups to polymer chains to form a functionalized polymer, and the functionalized polymer reduces the 50°C hysteresis loss of carbon black-filled vulcanized products prepared from the functionalized polymer compared to similar carbon black-filled vulcanized products prepared from unfunctionalized polymers. In these or embodiments, the functionalizers impart functional groups to polymer chains to form a functionalized polymer, and the functionalized polymer reduces the 50°C hysteresis loss of silica black-filled vulcanized products prepared from the functionalized polymer compared to similar silica-filled vulcanized products prepared from unfunctionalized polymers. In one or more embodiments, this reduction in hysteresis loss is at least 5% (in either the carbon black-filled or silica-filled composition), at least 10% in other embodiments, and at least 15% in other embodiments.

[0070] Silica filler Suitable silica packing materials include precipitated amorphous silica, wet silica (hydrated silica), dry silica (anhydrous silica), fumed silica, calcium silicate, aluminum silicate, and magnesium silicate.

[0071] In one or more embodiments, silica can be characterized by its surface area, which serves as a measure of its reinforcing properties. The Brunauer, Emmet, and Teller ("BET") method (described in J.Am.Chem.Soc., vol.60, p.309 et seq.) is a recognized method for determining surface area. The BET surface area of ​​silica is generally 450 m². 2 It is less than / g. The useful range for surface area is approximately 32 to 400 m². 2 / g, about 100~250m 2 / g, and approximately 150-220m 2 / g is one example.

[0072] When using one or more silica particles, the pH of the silica is generally about 5 to about 7, or slightly higher than 7, but in other embodiments it is about 5.5 to about 6.8.

[0073] In one or more embodiments, when silica is used as a filler (alone or in combination with other fillers), coupling agents and / or shielding agents may be added to the rubber composition during mixing to enhance the interaction between silica and the elastomer. Useful coupling agents and shielding agents are listed in U.S. Patents No. 3,842,111, 3,873,489, 3,978,103, 3,997,581, 4,002,594, 5,580,919, 5,583,245, 5,663,396, 5,674,932, and 5,684,171. These are disclosed in Patent Nos. 5,684,172, 5,696,197, 6,608,145, 6,667,362, 6,579,949, 6,590,017, 6,525,118, 6,342,552, and 6,683,135, which are incorporated herein by reference. Examples of sulfur-containing silica coupling agents include bis(trialkoxysilylorgano)polysulfides or mercapto-organoalkoxysilanes. Types of bis(trialkoxysilylorgano)polysulfides include bis(trialkoxysilylorgano)disulfide and bis(trialkoxysilylorgano)tetrasulfide.

[0074] hardening agent As described above, the vulcanizable composition of the present invention includes a curing system. The curing system includes a curing agent, which may also be called a rubber curing agent or vulcanizing agent. Curing agents are described in Kirk-Othmer, ENCYCLOPEDIA OF CHEMICAL TECHNOLOGY, Vol.20, pp.365-468, (3rd Ed.1982), in particular in Vulcanization Agents and Auxiliary Materials, pp.390-402, and AYCoran, Vulcanization, ENCYCLOPEDIA OF POLYMER SCIENCE AND ENGINEERING, (2nd Ed.1989), which are incorporated herein by reference. In one or more embodiments, a useful curing system includes sulfur or a sulfur-based curing agent. Suitable examples of sulfur vulcanizing agents include sulfur-donating agents such as soluble sulfur, disulfide amines, polymeric polysulfides, or sulfur-olefin adducts from "rubbermakers," as well as insoluble polymeric sulfur. The vulcanizing agents may be used alone or in combination. Those skilled in the art will be able to easily select the amount of vulcanizing agent to achieve the desired curing level.

[0075] In one or more embodiments, the curing agent is used in combination with a curing accelerator. In one or more embodiments, the accelerator is used to control the time and / or temperature required for vulcanization and to improve the properties of the vulcanized rubber. Examples of accelerators include thiazole vulcanization accelerators (e.g., 2-mercaptobenzothiazole, dibenzothiazyl disulfide, and N-cyclohexyl-2-benzothiazyl-sulfenamide (CBS)) and guanidine vulcanization accelerators (e.g., diphenylguanidine (DPG)). Those skilled in the art will be able to easily select the amount of curing accelerator to achieve the desired level of curing.

[0076] Metal activators and organic acids As described above, the vulcanizing composition of the present invention contains a metal compound. In one or more embodiments, the metal compound is an activator (i.e., an agent that assists in the vulcanization or curing of rubber). In other embodiments, the metal activator is a metal oxide. In certain embodiments, the metal activator is a zinc species formed in situ through a reaction or interaction between zinc oxide and an organic acid (e.g., stearic acid). In other embodiments, the metal compound is a magnesium compound such as magnesium hydroxide. In other embodiments, the metal compound is an iron compound such as iron oxide. In other embodiments, the metal compound is a cobalt compound such as cobalt carboxylate. In one or more embodiments, the organic acid is a carboxylic acid. In certain embodiments, the carboxylic acid is a fatty acid, including saturated and unsaturated fatty acids. In certain embodiments, a saturated fatty acid such as stearic acid is used. Other useful acids include, but are not limited to, palmitic acid, arachidic acid, oleic acid, linoleic acid, and arachidonic acid.

[0077] Silica coupling agent In one or more embodiments, coupling agents and / or shielding agents may be added to the vulcanizable rubber composition. As those skilled in the art will understand, coupling agents can enhance the interaction between silica and a functionalized polymer (e.g., synthetic functionalized polyisoprene). Useful coupling agents and shielding agents are listed in U.S. Patents No. 3,842,111, 3,873,489, 3,978,103, 3,997,581, 4,002,594, 5,580,919, 5,583,245, 5,663,396, 5,674,932, and 5,684,171. These are disclosed in Patent Nos. 5,684,172, 5,696,197, 6,608,145, 6,667,362, 6,579,949, 6,590,017, 6,525,118, 6,342,552, and 6,683,135, which are incorporated herein by reference. Examples of sulfur-containing silica coupling agents include bis(trialkoxysilylorgano)polysulfides or mercapto-organoalkoxysilanes. Types of bis(trialkoxysilylorgano)polysulfides include bis(trialkoxysilylorgano)disulfide and bis(trialkoxysilylorgano)tetrasulfide.

[0078] Carbon black filler As described above, the vulcanizable composition of the present invention may contain one or more fillers. These filler materials may include reinforcing fillers and non-reinforcing fillers. Examples of fillers include carbon black, silica, and various inorganic fillers.

[0079] Useful carbon blacks include furnace black, channel black, and lamp black. More specific examples of carbon black include ultra-abrasive furnace black, intermediate ultra-abrasive furnace black, high-abrasive furnace black, high-speed extruded furnace black, fine furnace black, semi-reinforced furnace black, medium-machined channel black, hard-machined channel black, conductive channel black, and acetylene black.

[0080] In one or more embodiments, the carbon black may have a surface area greater than 60 g / kg, as defined by the iodine absorption number determined by ASTM D1510; in other embodiments, it may have a surface area greater than 70 g / kg; in other embodiments, greater than 80 g / kg; and in other embodiments, greater than 90 g / kg. In these or other embodiments, the carbon black is measured by the Brunauer, Emmet and Teller ("BET") method (described in J.Am.Chem.Soc., vol.60, p.309 onwards) to be approximately 70–200 m 2 / g, in other embodiments approximately 100 to approximately 180m 2 / g, and in other embodiments, approximately 110 to approximately 160m 2 It may have a surface area of ​​ / g. The carbon black may be in pelletized form or in unpelleted, cotton-like form. The preferred form of carbon black may depend on the type of mixing equipment used to mix the rubber compound.

[0081] In one or more embodiments, useful carbon blacks can be characterized as N-300 series or lower carbon blacks according to ASTM D1765. Examples of these carbon blacks include N-100 series, N-200 series, and N-300 series carbon blacks. Exemplary N-100 series carbon blacks include N-100, N-115, N-120, N-121, N-125, N-134, and N-135 carbon blacks. Exemplary N-200 series carbon blacks include N-220, N-231, N-294, and N-299. Exemplary N-300 series carbon blacks include N-326, N-330, N-335, N-343, N-347, N-351, N-356, N-358, and N-375.

[0082] Other fillers Other useful filler materials include various inorganic and organic fillers. An example of an organic filler is starch. Examples of inorganic fillers include silica, aluminum hydroxide, magnesium hydroxide, titanium dioxide, boron nitride, iron oxide, mica, talc (hydrated magnesium silicate), and clay (hydrated aluminum silicate).

[0083] resin In one or more embodiments, the vulcanizable composition of the present invention may contain one or more resins. As will be understood by those skilled in the art, the resins may include plasticizers and curable or thermosetting resins. Useful plasticizers include hydrocarbon resins such as alicyclic resins, aliphatic resins, aromatic resins, terpene resins, and combinations thereof. Useful resins are commercially available under various brand names from various companies, including, for example, Chemfax, Dow Chemical Company, Eastman Chemical Company, Idemitsu, Neville Chemical Company, Nippon, Polysat Inc., Resinall Corp., Pinova Inc., Yasuhara Chemical Co., Ltd., Arizona Chemical, and SI Group Inc., and Zeon.

[0084] In one or more embodiments, the useful hydrocarbon resin may be characterized by a glass transition temperature (Tg) of about 30 to about 160°C, in other embodiments about 35 to about 60°C, and in other embodiments about 70 to about 110°C. In one or more embodiments, the useful hydrocarbon resin may also be characterized by its softening point being higher than its glass transition temperature (Tg). In certain embodiments, the useful hydrocarbon resin has a softening point of about 70 to about 160°C, in other embodiments about 75 to about 120°C, and in other embodiments about 120 to about 160°C.

[0085] In certain embodiments, one or more alicyclic resins are used in combination with one or more aliphatic resins, aromatic resins, and terpene resins. In one or more embodiments, one or more alicyclic resins are used as the main weight component (e.g., a component exceeding 50% by weight) of the total amount of resin. For example, the resin used contains one or more alicyclic resins in an amount of at least 55% by weight, at least 80% by weight in other embodiments, and at least 99% by weight in other embodiments.

[0086] In one or more embodiments, the alicyclic resin comprises both alicyclic homopolymer resins and alicyclic copolymer resins, the alicyclic copolymer resins optionally include those derived from alicyclic monomers combined with one or more other (non-alicyclic) monomers (where the majority of the monomers are alicyclic). Non-limiting examples of suitable and useful alicyclic resins include cyclopentadiene ("CPD") homopolymer or copolymer resins, dicyclopentadiene ("DCPD") homopolymer or copolymer resins, and combinations thereof. Non-limiting examples of cyclic aliphatic copolymer resins include CPD / vinyl aromatic copolymer resins, DCPD / vinyl aromatic copolymer resins, CPD / terpene copolymer resins, DCPD / terpene copolymer resins, CPD / aliphatic copolymer resins (e.g., CPD / C5 fraction copolymer resins), DCPD / aliphatic copolymer resins (e.g., DCPD / C5 fraction copolymer resins), CPD / aromatic copolymer resins (e.g., CPD / C9 fraction copolymer resins), DCPD / aromatic copolymer resins (e.g., DCPD / C9 fraction copolymer resins), and CPD / aromatic Examples include aliphatic copolymer resins (e.g., CPD / C5 and C9 fraction copolymer resins), DCPD / aromatic-aliphatic copolymer resins (e.g., DCPD / C5 and C9 fraction copolymer resins), CPD / vinyl aromatic copolymer resins (e.g., CPD / styrene copolymer resins), DCPD / vinyl aromatic copolymer resins (e.g., DCPD / styrene copolymer resins), CPD / terpene copolymer resins (e.g., limonene / CPD copolymer resins), and DCPD / terpene copolymer resins (e.g., limonene / DCPD copolymer resins). In certain embodiments, the alicyclic resin may include one of the above-mentioned alicyclic resins in a hydrogenated form (i.e., a hydrogenated alicyclic resin). In other embodiments, the alicyclic resin excludes any hydrogenated alicyclic resin. In other words, the alicyclic resin is not hydrogenated.

[0087] In certain embodiments, one or more aromatic resins are used in combination with one or more aliphatic resins, alicyclic resins, and terpene resins. In one or more embodiments, one or more aromatic resins are used as the main weight component (for example, a component exceeding 50% by weight) of the total amount of resin. For example, the resin used contains one or more aromatic resins in an amount of at least 55% by weight, at least 80% by weight in other embodiments, and at least 99% by weight in other embodiments.

[0088] In one or more embodiments, the aromatic resin includes both aromatic homopolymer resins and aromatic copolymer resins, the aromatic copolymer resins including those derived from a combination of one or more aromatic monomers with one or more other (non-aromatic) monomers (wherein the most abundant monomer of any kind is aromatic). Useful non-limiting examples of aromatic resins include coumarone-indene resins and alkyl-phenol resins, as well as vinyl aromatic homopolymer or copolymer resins, for example, these resins derived from one or more vinyl aromatic monomers obtained from alpha-methylstyrene, styrene, ortho-methylstyrene, meta-methylstyrene, para-methylstyrene, vinyltoluene, para-(tert-butyl)styrene, methoxystyrene, chlorostyrene, hydroxystyrene, vinyl mesitylene, divinylbenzene, vinylnaphthalene, or any vinyl aromatic monomers obtained from the C9 fraction or C8-C10 fraction. Non-limiting examples of vinyl aromatic copolymer resins include vinyl aromatic / terpene copolymer resins (e.g., limonene / styrene copolymer resins), vinyl aromatic / C5 fraction resins (e.g., C5 fraction / styrene copolymer resins), and vinyl aromatic / aliphatic copolymer resins (e.g., CPD / styrene copolymer resins, and DCPD / styrene copolymer resins). Non-limiting examples of alkyl-phenol resins include p-tert-butylphenol-acetylene resins and alkylphenol-formaldehyde resins (e.g., alkylphenol-acetylene resins such as resins with a low degree of polymerization). In certain embodiments, the aromatic resin may include one of the above-mentioned aromatic resins in a hydrogenated form (i.e., a hydrogenated aromatic resin). In other embodiments, the aromatic resin excludes any hydrogenated aromatic resins. In other words, the aromatic resin is not hydrogenated.

[0089] In certain embodiments, one or more aliphatic resins are used in combination with one or more alicyclic resins, aromatic resins, and terpene resins. In one or more embodiments, one or more aliphatic resins are used as the main weight component (e.g., a component exceeding 50% by weight) of the total amount of resin. For example, the resin used contains one or more aliphatic resins in an amount of at least 55% by weight, at least 80% by weight in other embodiments, and at least 99% by weight in other embodiments.

[0090] In one or more embodiments, the aliphatic resin includes both aliphatic homopolymer resins and aliphatic copolymer resins, the aliphatic copolymer resins including those derived from a combination of one or more aliphatic monomers with one or more other (non-aliphatic) monomers (wherein any monomer, the most abundant component is aliphatic). Non-limiting examples of useful aliphatic resins include C5 fraction homopolymer or copolymer resins, C5 fraction / C9 fraction copolymer resins, C5 fraction / vinyl aromatic copolymer resins (e.g., C5 fraction / styrene copolymer resins), C5 fraction / alicyclic copolymer resins, and C5 fraction / C9 fraction / alicyclic copolymer resins, as well as combinations thereof. Non-limiting examples of cyclic aliphatic monomers include, but are not limited to, cyclopentadiene ("CPD") and dicyclopentadiene ("DCPD"). In certain embodiments, the aliphatic resin may include one hydrogenated form of the above aliphatic resins (i.e., a hydrogenated aliphatic resin). In other embodiments, the aliphatic resin excludes any hydrogenated aliphatic resin. In other words, in such embodiments, the aliphatic resin is not hydrogenated.

[0091] In one or more embodiments, the terpene resin includes both terpene homopolymer resins and terpene copolymer resins, the terpene copolymer resins including those derived from a combination of one or more terpene monomers with one or more other (non-terpene) monomers (wherein any monomer, terpene is the most abundant component). Non-limiting examples of useful terpene resins include α-pinene resins, β-pinene resins, limonene resins (e.g., L-limonene, D-limonene, and even dipentene, which is a racemic mixture of L-isomers and D-isomers), β-phellandrene, δ-3-carene, δ-2-carene, pinene-limonene copolymer resins, terpene phenol resins, and aromatically modified terpene resins, as well as combinations thereof. In certain embodiments, the terpene resin may include one hydrogenated form of the above terpene resins (i.e., a hydrogenated terpene resin). In other embodiments, the terpene resin excludes any hydrogenated terpene resins. In other words, in this embodiment, the terpene resin is not hydrogenated.

[0092] processing oil In one or more embodiments, the vulcanizing composition of the present invention includes a processing oil, which may also be referred to as an extender oil. In one or more embodiments, the vulcanizing composition lacks or substantially lacks a processing oil.

[0093] In certain embodiments, oils used include those conventionally used as extender oils. Useful oils or extenders that may be used include, but are not limited to, aromatic oils, paraffinic oils, naphthenic oils, vegetable oils (other than castor oil), low PCA oils (e.g., MES, TDAE, and SRAE), and heavy naphthenic oils. Suitable low PCA oils also include oils of various plant origins, such as those extracted from vegetables, nuts, and seeds. Non-limiting examples include, but are not limited to, soy or soybean oil, sunflower oil, safflower oil, corn oil, linseed oil, cottonseed oil, rapeseed oil, cashew oil, sesame oil, camellia oil, jojoba oil, macadamia nut oil, coconut oil, and palm oil. As is generally understood in the art, oil refers to a compound having a viscosity that is relatively comparable to other components of a vulcanizing composition, such as a resin.

[0094] In one or more embodiments, the oil contains hydrocarbon compounds having more than 15 carbon atoms per molecule, in other embodiments more than 20, in other embodiments more than 25, in other embodiments more than 30, in other embodiments more than 35, and in other embodiments more than 40 carbon atoms. In these or other embodiments, the oil contains hydrocarbon compounds having fewer than 250 carbon atoms per molecule, in other embodiments less than 200, in other embodiments less than 150, in other embodiments less than 120, in other embodiments less than 100, in other embodiments less than 90, in other embodiments less than 80, in other embodiments less than 70, in other embodiments less than 60, and in other embodiments less than 50 carbon atoms. In one or more embodiments, the oil comprises hydrocarbon compounds having about 15 to about 250 carbon atoms, in other embodiments about 20 to about 200 carbon atoms, in other embodiments about 25 to about 100 carbon atoms per molecule, in other embodiments about 25 to about 70 carbon atoms per molecule, in other embodiments about 25 to about 70 carbon atoms per molecule, in other embodiments about 25 to about 60 carbon atoms per molecule, and in other embodiments about 25 to about 40 carbon atoms per molecule.

[0095] In one or more embodiments, the oil comprises a compound having a dynamic viscosity greater than 5 mPa·s at 25°C, in other embodiments greater than 10 mPa·s, in other embodiments greater than 15 mPa·s, in other embodiments greater than 20 mPa·s, in other embodiments greater than 25 mPa·s, in other embodiments greater than 30 mPa·s, in other embodiments greater than 35 mPa·s, and in other embodiments greater than 40 mPa·s. In these or other embodiments, the oil comprises a compound having a dynamic viscosity of less than 3000 mPa·s at 25°C, less than 2500 mPa·s in other embodiments, less than 2000 mPa·s in other embodiments, less than 1500 mPa·s in other embodiments, less than 1000 mPa·s in other embodiments, less than 750 mPa·s in other embodiments, less than 500 mPa·s in other embodiments, less than 250 mPa·s in other embodiments, less than 100 mPa·s in other embodiments, and a hydrocarbon compound having a dynamic viscosity of less than 75 mPa·s in other embodiments. In one or more embodiments, the oil comprises a compound having a dynamic viscosity of about 5 to about 3000 mPa·s at 25°C, in other embodiments about 15 to about 2000 mPa·s, in other embodiments about 20 to about 1500 mPa·s, in other embodiments about 25 to about 1000 mPa·s, in other embodiments about 30 to about 750 mPa·s, in other embodiments about 35 to about 500 mPa·s, and in other embodiments about 50 to about 250 mPa·s.

[0096] Other optional components Other components typically used in rubber compounding can also be added to the rubber composition. These include accelerators, activators, plasticizers, waxes, anticorrosion agents, processing aids, zinc oxide, tackifying resins, reinforcing resins, fatty acids (e.g., stearic acid), decoagulants, and degradation inhibitors (e.g., antioxidants and ozone degradation inhibitors).

[0097] Ingredient amount rubber As described above, the rubber-based vulcanizable composition contains vulcanizable rubber components. In one or more embodiments, the rubber-based vulcanizable composition contains more than 20% by weight, more than 30% by weight in other embodiments, and more than 40% by weight in other embodiments, based on the total weight of the composition, of vulcanizable rubber components (which may simply be called the vulcanizable composition). In these or other embodiments, the vulcanizable composition contains less than 90% by weight, less than 70% by weight in other embodiments, and less than 60% by weight in other embodiments, based on the total weight of the vulcanizable composition, of rubber components. In one or more embodiments, the vulcanizable composition contains about 20 to about 90% by weight, about 30 to about 70% by weight in other embodiments, and about 40 to about 60% by weight in other embodiments, based on the total weight of the vulcanizable composition, of rubber components.

[0098] filling material In one or more embodiments, the vulcanizable composition contains more than 0 parts by weight (pbw) of filler per 100 parts by weight (phr) of rubber, and in other embodiments, more than 10 pbw, more than 25 pbw, more than 35 pbw, more than 45 pbw, more than 55 pbw, and more than 65 pbw of filler. In these or other embodiments, the vulcanizable composition contains less than 200 pbw (phr) of silica, and in other embodiments, less than 150 pbw (phr), less than 120 pbw (phr), less than 100 pbw (phr), less than 80 pbw (phr), and less than 70 pbw (phr) of filler. In one or more embodiments, the vulcanizable composition contains a filler in an amount of about 20 to about 100 pbw(phr), in other embodiments about 35 to about 80 pbw(phr), and in other embodiments about 40 to about 70 pbw(phr).

[0099] Carbon Black In one or more embodiments, the vulcanizable composition contains more than 0 parts by weight (pbw) of carbon black per 100 parts by weight (phr) of rubber, more than 1 pbw in other embodiments, more than 2 pbw in other embodiments, more than 5 pbw in other embodiments, more than 10 pbw in other embodiments, and more than 15 pbw in other embodiments. In these or other embodiments, the vulcanizable composition contains less than 60 pbw (phr), less than 40 pbw (phr) in other embodiments, and less than 30 pbw (phr) in other embodiments. In one or more embodiments, the vulcanizable composition contains about 1 to about 60 pbw (phr) of carbon black, about 5 to about 50 pbw (phr) in other embodiments, and about 10 to about 40 pbw (phr) in other embodiments. In one or more embodiments, the vulcanizable composition lacks or substantially lacks carbon black.

[0100] silica In one or more embodiments, the vulcanizable composition contains more than 5 parts by weight (pbw) of silica per 100 parts by weight (phr) of rubber, more than 7 pbw in other embodiments, more than 10 pbw in other embodiments, more than 15 pbw in other embodiments, and more than 20 pbw in other embodiments. In these or other embodiments, the vulcanizable composition contains less than 80 pbw (phr), less than 70 pbw (phr) in other embodiments, less than 60 pbw (phr) in other embodiments, less than 50 pbw (phr) in other embodiments, and less than 40 pbw (phr) in other embodiments. In one or more embodiments, the vulcanizable composition contains about 5 to about 80 pbw (phr), about 10 to about 60 pbw (phr) in other embodiments, and about 15 to about 40 pbw (phr) of silica.

[0101] Filler ratio In one or more embodiments, the vulcanizable composition can be characterized by the ratio of silica to other filler compounds such as carbon black. In one or more embodiments, silica is used in excess of other fillers such as carbon black. In one or more embodiments, the ratio of silica to carbon black silica is greater than 1:1, greater than 1.3:1 in other embodiments, greater than 1.5:1 in other embodiments, and greater than 2:1 in other embodiments, based on weight ratio. In one or more embodiments, the weight ratio of silica to carbon black is about 1:1 to about 3:1, about 1.3 to about 2.5:1 in other embodiments, and about 1.5 to about 2:1 in other embodiments.

[0102] Silica coupling agent In one or more embodiments, the vulcanizable composition contains more than 1 part by weight (pbw) of silica coupling agent per 100 parts by weight of silica, more than 2 pbw in other embodiments, and more than 5 pbw in other embodiments. In these or other embodiments, the vulcanizable composition contains less than 20 pbw of silica coupling agent per 100 parts by weight of silica, less than 15 pbw in other embodiments, and less than 10 pbw in other embodiments. In one or more embodiments, the vulcanizable composition contains about 1 to about 20 pbw of silica coupling agent per 100 parts by weight, about 2 to about 15 pbw in other embodiments, and about 5 to about 10 pbw in other embodiments. In one or more embodiments, the vulcanizable composition lacks or substantially lacks silica coupling agent.

[0103] plasticized resin In one or more embodiments, the vulcanizable composition contains more than 0.1 parts by weight (pbw) of a plasticizing resin (e.g., a hydrocarbon resin) per 100 parts by weight (phr) of rubber, and in other embodiments, more than 0.5 pbw, more than 1.0 pbw, more than 1.5 pbw, more than 15 pbw, and more than 25 pbw of a plasticizing resin (e.g., a hydrocarbon resin). In these or other embodiments, the vulcanizable composition comprises a plasticizing resin (e.g., a hydrocarbon resin) with a strength of less than 150 pbw(phr), in other embodiments less than 120 pbw(phr), in other embodiments less than 90 pbw(phr), in other embodiments less than 80 pbw(phr), in other embodiments less than 60 pbw(phr), in other embodiments less than 45 pbw(phr), in other embodiments less than 15 pbw(phr), in other embodiments less than 10 pbw(phr), and in other embodiments less than 3.0 pbw(phr). In one or more embodiments, the vulcanizable composition comprises about 1 to about 150 pbw(phr) of plasticizing resin (e.g., hydrocarbon resin), in other embodiments about 0.5 to about 15 pbw(phr), in other embodiments about 1 to about 10 pbw(phr), in other embodiments about 1.5 to about 3 pbw(phr), in other embodiments about 15 to about 100 pbw(phr), and in other embodiments about 25 to about 80 pbw(phr) of plasticizing resin (e.g., hydrocarbon resin). In one or more embodiments, the vulcanizable composition lacks or substantially lacks plasticizing resin.

[0104] Processing / Extender Oil In one or more embodiments, the vulcanizing composition contains more than 0.1 parts by weight (pbw) of processing oil (e.g., naphthenic oil) per 100 parts by weight (phr) of rubber, and in other embodiments, more than 0.5 pbw, in other embodiments, more than 1 pbw, in other embodiments, more than 1.5 pbw, and in other embodiments, more than 2 pbw of processing oil (naphthenic oil). In these or other embodiments, the vulcanizing composition contains less than 20 pbw (phr) of processing oil, in other embodiments, less than 18 (phr), in other embodiments, less than 15 pbw (phr), in other embodiments, less than 12 pbw (phr), in other embodiments, less than 10 pbw (phr), in other embodiments, less than 8 pbw (phr), in other embodiments, less than 5 pbw (phr), and in other embodiments, less than 3 pbw (phr). In one or more embodiments, the vulcanizing composition contains about 0.1 to about 20 pbw(phr) of oil; in other embodiments, about 0.5 to about 18 pbw(phr); in other embodiments, about 0.5 to about 15 pbw(phr); in other embodiments, about 1 to about 10 pbw(phr); in other embodiments, about 0.5 to about 18 pbw(phr); in other embodiments, about 1.5 to about 3.0 pbw(phr); and in other embodiments, about 2 to about 12 pbw(phr) of oil. In one or more embodiments, the vulcanizing composition is devoid of or substantially devoid of oil.

[0105] Plasticizing additives In one or more embodiments, the plasticizing resin and processing oil may be collectively referred to as plasticizing additives, plasticizing components, plasticizing components, or plasticizing systems. In one or more embodiments, the vulcanizable composition contains more than 0.5 parts by weight (pbw) of plasticizing additive per 100 parts by weight (phr) of rubber, more than 1 pbw in other embodiments, and more than 1.5 pbw in other embodiments. In these or other embodiments, the vulcanizable composition contains less than 15 pbw (phr) of plasticizing additive, less than 12 pbw (phr) in other embodiments, less than 10 pbw (phr) in other embodiments, less than 5 pbw (phr) in other embodiments, and less than 3 pbw (phr) in other embodiments. In one or more embodiments, the vulcanizable composition contains a plasticizing additive in an amount of about 0.5 to about 15 pbw(phr), in other embodiments about 1 to about 10 pbw(phr), and in other embodiments about 1.5 to about 3 pbw(phr).

[0106] hardening resin In one or more embodiments, the vulcanizable composition contains a curable resin of less than 2 pbw(phr), in other embodiments less than 1 pbw(phr), and in other embodiments less than 0.5 pbw(phr). In one or more embodiments, the vulcanizable composition contains a curable resin of about 0.1 to about 8 pbw(phr), in other embodiments about 0.5 to about 6 pbw(phr), and in other embodiments about 2 to about 4 pbw(phr). In one or more embodiments, the vulcanizable composition lacks or substantially lacks a curable resin.

[0107] sulfur In one or more embodiments, the vulcanizing composition contains sulfur as a curing agent. In one or more embodiments, the vulcanizing composition contains more than 0.1 parts by weight (pbw) of sulfur per 100 parts by weight (phr) of rubber, more than 0.3 pbw in other embodiments, and more than 0.9 pbw in other embodiments. In these or other embodiments, the vulcanizing composition contains less than 6 pbw (phr) of sulfur, less than 4 pbw (phr) in other embodiments, less than 3.0 pbw (phr) in other embodiments, and less than 2.0 pbw (phr) in other embodiments. In one or more embodiments, the vulcanizing composition contains about 0.1 to about 5.0 pbw (phr) of sulfur, about 0.8 to about 2.5 pbw (phr) in other embodiments, about 1 to about 2.0 pbw (phr) in other embodiments, and about 1.0 to about 1.8 pbw (phr) of sulfur.

[0108] Process Overview In one or more embodiments, the vulcanizable composition is prepared by mixing vulcanizable rubber and a filler to create a masterbatch, to which a curing agent is subsequently added. The preparation of the masterbatch may be carried out using one or more auxiliary mixing steps, in which, for example, an initial mixture may be prepared by mixing two or more components, and then one or more components may be added sequentially to the composition. In addition, additional components may be added to the preparation of the vulcanizable composition using the prior art, and such additional components include, but are not limited to, carbon black, additional fillers, silica, silica coupling agents, silica dispersants, processing oils, processing aids (e.g., zinc oxide and fatty acids), and degradation inhibitors (or antioxidants or ozone degradation inhibitors).

[0109] Mixing conditions In one or more embodiments, various components of the rubber composition (e.g., natural rubber, functionalized synthetic polyisoprene, and butadiene-based rubber) are optionally introduced into the vulcanizable rubber as initial components in the formation of a rubber masterbatch, along with carbon black and silica fillers. As a result, these components undergo mixing under high shear and high temperature. In one or more embodiments, this masterbatch mixing step is carried out at a minimum temperature above 110°C, in other embodiments at a minimum temperature above 130°C, and in other embodiments at a minimum temperature above 150°C. In one or more embodiments, the high-shear, high-temperature mixing is carried out at a temperature of about 110°C to about 170°C. In one or more embodiments, the masterbatch mixing step, or one or more sub-steps of the masterbatch mixing step, can be characterized by the peak temperature reached by the composition during mixing. This peak temperature may also be called the drop temperature. In one or more embodiments, the peak temperature of the composition during the masterbatch mixing step may be at least 140°C, in other embodiments at least 150°C, and in other embodiments at least 160°C. In these or other embodiments, the peak temperature of the composition during the masterbatch mixing step may be about 140 to about 200°C, in other embodiments about 150 to about 190°C, and in other embodiments about 160 to about 180°C.

[0110] After the initial mixing, the composition (i.e., the masterbatch) is cooled to a temperature below 100°C, or below 80°C in other embodiments, before the curing agent is added. Mixing is continued at a temperature of about 90–110°C in certain embodiments, or about 95–105°C in other embodiments, to prepare the final vulcanizable composition. Following the masterbatch mixing step, the curing agent or curing agent system is introduced into the composition, and mixing is continued to finally form the vulcanizable composition. This mixing step may be referred to as the final mixing step, curing agent mixing step, or production mixing step. The product obtained from this mixing step may be referred to as the vulcanizable composition.

[0111] In one or more embodiments, the final mixing step can be characterized by the peak temperature reached by the composition during the final mixing. As those skilled in the art will recognize, this temperature may also be referred to as the final drop temperature. In one or more embodiments, the peak temperature of the composition during the final mixing may be up to 130°C, up to 110°C in other embodiments, and up to 100°C in other embodiments. In these or other embodiments, the peak temperature of the composition during the final mixing may be about 80 to about 130°C, up to about 90 to about 115°C in other embodiments, and up to about 95 to about 105°C in other embodiments.

[0112] mixing equipment All components of the vulcanizable composition can be mixed using standard mixing equipment, such as built-in mixers (e.g., Banbury or Brabender mixers, extruders, kneaders, and two-roll mills). Mixing can be done individually or in parallel. As described above, the components can be mixed in a single step, or in other embodiments, in two or more steps. For example, in a first step (i.e., a mixing step), a masterbatch (typically containing rubber components and fillers) is prepared. Once the masterbatch is prepared, in a final mixing step, the vulcanizing agent may be introduced into the masterbatch and mixed. This final mixing step is typically carried out at a relatively low temperature to reduce the possibility of premature vulcanization. An additional mixing step, sometimes called a remill, can be employed between the masterbatch mixing step and the final mixing step.

[0113] Tire adjustment The vulcanizable composition can be processed into tire components according to conventional tire manufacturing techniques, including standard rubber molding, shaping, and curing techniques. Typically, vulcanization is carried out by heating the vulcanizable composition in a mold, which may be heated to, for example, about 140°C to about 180°C. The cured or crosslinked rubber composition may also be referred to as a vulcanized product, which generally contains a thermosetting three-dimensional polymer network structure. Other components, such as fillers and processing aids, may be uniformly dispersed throughout the crosslinked network structure. Pneumatic tires can be manufactured as described in U.S. Patents 5,866,171, 5,876,527, 5,931,211, and 5,971,046, which are incorporated herein by reference.

[0114] Industrial applicability As described above, various tire components can be prepared by curing the vulcanizable composition of the present invention. These tire components include, but are not limited to, the tire tread, tire sidewall, belt skim, inner liner, price skim, and bead apex. These tire components may be included in tires for various vehicles, including passenger cars.

[0115] In certain embodiments, the vulcanized product of the present invention includes one or more components of a heavy vehicle tire, such as the tread or undertread of a heavy vehicle tire. As will be understood by those skilled in the art, examples of heavy vehicle tires include truck tires, bus tires, TBR (truck and bus tires), subway tires, tractor tires, trailer tires, aircraft tires, agricultural tires, earth mover tires, and other off-road (OTR) tires. In one or more embodiments, the heavy vehicle tires may be new tires as well as retreaded tires. Heavy vehicle tires may sometimes be classified according to their application. For example, truck tires may be classified as drive tires (powered by the truck engine) and steering tires (used to steer the truck). The tires of trailers on tractor-trailer rigs are also classified separately.

[0116] In certain embodiments, the heavy-duty vehicle tire is a relatively large tire. In one or more embodiments, the heavy-duty vehicle tire has an overall diameter (tread to tread) of more than 17.5 inches, and in other embodiments, an overall diameter of more than 20 inches, more than 25 inches, more than 30 inches, more than 40 inches, and more than 55 inches. In these or other embodiments, the heavy-duty vehicle tire has a cross-sectional width of more than 10 inches, more than 11 inches, more than 12 inches, and more than 14 inches.

[0117] In certain embodiments, heavy-duty vehicle tires are also characterized by their curing time (i.e., the amount of time required to achieve t90). In one or more embodiments, green (i.e., uncured) heavy-duty vehicle tires require a curing time of more than 30 minutes (to achieve t90), more than 1 hour in other embodiments, more than 5 hours in other embodiments, more than 10 hours in other embodiments, and more than 16 hours in other embodiments. [Examples]

[0118] To demonstrate the implementation of the present invention, the following examples were prepared and tested. However, these examples should not be considered limiting to the scope of the invention. The claims define the present invention.

[0119] Samples 1-9 Preparation of functionalized synthetic polyisoprene (triethoxysilane) Synthetic polyisoprene terminally functionalized with triethyloxy silane was prepared as follows: A 2-gallon stainless steel reaction vessel packed with hexane (3,801 g) and isoprene (635 g) was treated with n-BuLi (1.30 mL of a 2.45 M solution in hexane) and 2,2-di(2-tetrahydrofuryl)propane (0.99 mL of a 0.16 M solution in hexane), and immediately thereafter the vessel jacket temperature was raised to 50°C. Polymerization reached a peak temperature of 69°C 30 minutes after the start of polymerization. 15 minutes after the peak polymerization temperature, 3-(1,3-dimethylbutylidene)aminopropyltriethoxysilane (1.12 mL), diluted in approximately 20 mL of hexane, was added to the polymerization mixture. After stirring for a further 20 minutes, the vessel jacket temperature was lowered to 25°C, and a sample was taken to calculate the conversion rate. Once the batch temperature fell below 60°C, the batch was discharged into a solution of isopropyl alcohol (approximately 16 L) containing 2,5-di-tert-butyl-4-methylphenol (approximately 1.8 g / L of isopropyl alcohol) to solidify, and then drum-dried.

[0120] The functionalized polymer (referred to as IR-Si(OR)3) was analyzed and determined to have 243 kg / mol of Mn, 256 kg / mol of Mw, 75.1 mol% of cis-1,4-microstructure, 18.6 mol% of trans-1,4-microstructure, and 6.3 mol% of vinyl content. 65% by weight of the polymer was coupled, and the polymer had a Mooney viscosity of 27.9 and a T of -62.8°C. g It had the following characteristics: At a heating rate of 10°C / min, the glass transition temperature (T) was determined by differential scanning calorimetry (DSC) over the range of -120°C to 23°C. gThe following parameters were measured: number-average (Mn) molecular weight, weight-average (Mw) molecular weight, and polydispersity (PDI) were determined by gel permeation chromatography (GPC) using a TOSOH Ecosec HLC-8320 GPC system and a TOSOH TSKgel GMHxl-BS column with THF as the solvent. The system was calibrated using polystyrene (PS) standards and referenced to PS standards. To enable complete characterization of the 1,4-cis and 1,4-trans microstructures, vinyl microstructures with isoprene content (3,4-isoprene) were measured. 13 Polymer Mooney viscosity was determined by 13C NMR. Polymer Mooney viscosity was measured using a Monsanto Mooney viscometer. The ML(1+4) value was measured on a large rotor at 100°C for 4 minutes after a 1-minute warm-up time.

[0121] Preparation of functionalized synthetic polyisoprene (diethoxysilane) Synthetic polyisoprene terminally functionalized with diethoxysilane was prepared as follows: A 2-gallon stainless steel reaction vessel packed with hexane (3,801 g) and isoprene (635 g) was treated with n-BuLi (1.24 mL of a 2.56 M solution in hexane) and 2,2-di(2-tetrahydrofuryl)propane (0.10 mL of a 1.6 M solution in hexane), and immediately thereafter the vessel jacket temperature was raised to 50°C. Polymerization reached its peak temperature of 61°C 55 minutes after the start of polymerization. 15 minutes after the peak polymerization temperature, 3-(1,3-dimethylbutylidene)aminopropylmethyldiethoxysilane (1.07 mL), diluted in approximately 20 mL of hexane, was added to the polymerization mixture. After stirring for a further 30 minutes, the vessel jacket temperature was lowered to 25°C, and a sample was taken to calculate the conversion rate. Once the batch temperature fell below 60°C, the batch was discharged into a solution of isopropyl alcohol (approximately 16 L) containing 2,5-di-tert-butyl-4-methylphenol (approximately 1.8 g / L of isopropyl alcohol) to solidify, and then drum-dried.

[0122] The functionalized polymer (referred to as IR-Si(OR)2) was analyzed and determined to have 206 kg / mol of Mn, 257 kg / mol of Mw, 74.4 mol% of cis-1,4-microstructure, 17.2 mol% of trans-1,4-microstructure, and 8.4 mol% of vinyl content. 59% by weight of the polymer was coupled, and the polymer had a Mooney viscosity of 35.6 and a Tg of -62.4°C.

[0123] Preparation of vulcanized products The functionalized synthetic polyisoprene prepared above was introduced into a rubber formulation to form a vulcanizable composition, which was then vulcanized. The rubber formulation contained natural rubber and silica fillers as detailed in Tables I and II below. The rubber components of each sample were varied. Generally, the rubber components consisted of natural rubber, an alkoxysilane-terminated polymer, and a functionalized polybutadiene ("functionalized BR"). The functionalized polybutadiene was a medium vinyl polybutadiene with terminal cyclic amine groups. Two comparative alkoxysilane-terminated polymers were used. The first, labeled BR-Si(OR)2, was a polybutadiene with 3-(1,3-dimethylbutylidene)aminopropylmethyldiethoxysilane as the terminal group. Polybutadiene had a manganese content of 193 kg / mol, manganese content of 205 kg / mol, manganese content of 86.1 mol%, cis-1,4-microstructure, and vinyl content of 14 mol%, with 69% by weight of the polymer being coupled, and the polymer having a Tg of -91.9°C. The second material, labeled SBR-Si(OR)3, was poly(styrene-co-butadiene) terminally functionalized with 3-(1,3-dimethylbutylidene)aminopropyltriethoxysilane. Poly(styrene-co-butadiene) had a manganese content of 150 kg / mol, manganese content of 164 kg / mol, manganese content of 34% by weight, styrene content of 28.3 mol%, with 45% by weight of the polymer being coupled, and had a Tg of -47.8°C.

[0124] The vulcanizable composition was prepared in a 300g Brabender mixer using the three-step mixing procedure shown in Table I. The liming did not involve the addition of any components. The masterbatch stage was mixed at 50 rpm with a starting mixer temperature of 90°C for 5 minutes or until the sample reached 160°C (whichever came first). The liming stage was mixed at 50 rpm with a starting mixer temperature of 90°C for 3.0 minutes or until the sample reached 160°C (whichever came first). The final stage was mixed at 40 rpm with a starting mixer temperature of 60°C for 2.5 minutes or until the sample reached 100°C (whichever came first).

[0125] [Table 1]

[0126] The vulcanizable compositions were subjected to Mooney analysis. These samples were cured at 145°C for 33 minutes. The bonded rubber was measured by GPC analysis as described above. Mechanical properties were measured according to ASTM D-412. Dynamic rheological properties were determined using both temperature analysis and strain sweep analysis, as shown in Table II. The test results, as well as details of the rubber components, are shown in Table II below. When values ​​are indexed, a larger number represents a more desirable property. For example, a lower tanδ at 60°C is desirable, and therefore a larger index value represents a lower tanδ value.

[0127] [Table 2]

[0128] Samples 10-14 Preparation of non-functionalized polyisoprenes Non-functionalized synthetic polyisoprene polymers were prepared as follows: A stainless steel reaction vessel filled with hexane (9,362 g) and isoprene (1,524 g) was treated with n-BuLi (3.18 mL of a 1.6 M solution in hexane) and 2,2-di(2-tetrahydrofuryl)propane (0.16 mL of a 1.6 M solution in hexane), and immediately thereafter the vessel jacket temperature was raised to 50°C. Polymerization reached a peak temperature of 74°C 37 minutes after the start of polymerization. Five minutes after the peak polymerization temperature, the vessel jacket temperature was lowered to 25°C. Fifteen minutes after the peak polymerization temperature, a sample was taken and the conversion rate was calculated. When the batch temperature fell below 60°C, the batch was discharged into a solution of isopropyl alcohol (approximately 16 L) containing 2,5-di-tert-butyl-4-methylphenol (approximately 1.8 g / L of isopropyl alcohol) to solidify, and then drum-dried. The polyisoprene polymer, referred to as IR, was characterized by a Mp of 369 kg / mol, a Mooney viscosity of 23 (ML 1+4 @ 100℃), and a 3,4-vinyl content of 6.4%.

[0129] Preparation of functionalized high molecular weight polyisoprenes High molecular weight synthetic polyisoprene terminally functionalized with triethyloxysilane was prepared as follows: A stainless steel reaction vessel filled with hexane (9,362 g) and isoprene (1,524 g) was treated with n-BuLi (3.18 mL of 1.6 M solution in hexane) and 2,2-di(2-tetrahydrofuryl)propane (0.16 mL of 1.6 M solution in hexane), and immediately thereafter the vessel jacket temperature was raised to 50°C. Polymerization reached its peak temperature of 78°C 47 minutes after the start of polymerization. Five minutes after the peak polymerization temperature, a solution of 3-(1,3-dimethylbutylidene)aminopropyltriethoxysilane (3.2 mL of 1.6 M solution in hexane) was added to the reactant. Twelve minutes after the peak polymerization temperature, the vessel jacket temperature was lowered to 25°C, and a sample was taken to calculate the conversion rate. Once the batch temperature fell below 60°C, the batch was discharged into a solution of isopropyl alcohol (approximately 16 L) containing 2,5-di-tert-butyl-4-methylphenol (approximately 1.8 g / L of isopropyl alcohol) to solidify, and then drum-dried. The resulting polymer had a higher molecular weight than expected, which was attributed to unintended catalyst demand in polymerization that reduced the effective loading of the n-BuLi initiator. The functionalized polyisoprene polymer, designated hMW-IR, was characterized by an Mp of 695 kg / mol, a coupling of 52%, a Mooney viscosity of 92 (ML 1+4 @ 100°C), and a 3,4-vinyl content of 6.5%.

[0130] Preparation of functionalized polyisoprenes with medium molecular weight Medium molecular weight synthetic polyisoprene terminally functionalized with triethyloxysilane was prepared as follows: A stainless steel reaction vessel filled with hexane (9,362 g) and isoprene (1,524 g) was treated with n-BuLi (3.18 mL of 1.6 M solution in hexane) and 2,2-di(2-tetrahydrofuryl)propane (0.16 mL of 1.6 M solution in hexane), and immediately thereafter the vessel jacket temperature was raised to 50°C. Polymerization reached its peak temperature of 75°C 37 minutes after the start of polymerization. The functionalizing agent 3-(1,3-dimethylbutylidene)aminopropyltriethoxysilane (3.2 mL of 1.6 M solution in hexane; 1 mole of functionalizing agent / Li) was added to the reaction vessel 5 minutes after polymerization reached its peak temperature. 15 minutes after the peak polymerization temperature, the vessel jacket temperature was lowered to 25°C, and a sample was taken to calculate the conversion rate. Once the batch temperature fell below 60°C, the batch was discharged into a solution of isopropyl alcohol (approximately 16 L) containing 2,5-di-tert-butyl-4-methylphenol (approximately 1.8 g / L of isopropyl alcohol), allowed to solidify, and then drum-dried. The functionalized polyisoprene polymer, designated mMW-IR, was characterized by a Mp of 404 kg / mol, a coupling of 71%, a Mooney viscosity of 81 (ML 1+4 @ 100°C), and a 3,4-vinyl content of 6.5%.

[0131] Preparation of functionalized low molecular weight polyisoprenes Low molecular weight synthetic polyisoprene terminally functionalized with triethyloxysilane was prepared as follows: A stainless steel reaction vessel packed with hexane (9,362 g) and isoprene (1,524 g) was treated with n-BuLi (3.81 mL of 1.6 M solution in hexane) and 2,2-di(2-tetrahydrofuryl)propane (0.19 mL of 1.6 M solution in hexane), and immediately thereafter the vessel jacket temperature was raised to 50°C. Polymerization reached its peak temperature of 75°C 36 minutes after the start of polymerization. The functionalizing agent 3-(1,3-dimethylbutylidene)aminopropyltriethoxysilane (3.8 mL of 1.6 M solution in hexane; 1 mole of functionalizing agent / Li) was added to the reaction vessel 5 minutes after polymerization reached its peak temperature. 15 minutes after the peak polymerization temperature, the vessel jacket temperature was lowered to 25°C, and a sample was taken to calculate the conversion rate. Once the batch temperature fell below 60°C, the batch was discharged into a solution of isopropyl alcohol (approximately 16 L) containing 2,5-di-tert-butyl-4-methylphenol (approximately 1.8 g / L of isopropyl alcohol) to solidify, and then drum-dried. The functionalized polyisoprene polymer, designated lMW-IR, was characterized by a Mp of 335 kg / mol, a coupling of 72%, a Mooney viscosity of 63 (ML 1+4 @ 100°C), and a 3,4-vinyl content of 6.8%.

[0132] Preparation of vulcanized products The synthetic polyisoprenes prepared above (samples 11-13) were introduced into each rubber formulation to form vulcanizable compositions, which were then vulcanized and tested for various properties. An additional vulcanized product (sample 10) was prepared without synthetic polyisoprene. The rubber formulations contained natural rubber and silica fillers as detailed in Tables III and IV below. The rubber components of each sample were varied by including the aforementioned polymers as detailed in Table IV. As shown, the rubber components of each formulation contained natural rubber and unfunctionalized, high-cis polybutadiene rubber with a cis content exceeding 96%.

[0133] The vulcanizable composition was prepared in a 300g Brabender mixer using the three-step mixing procedure shown in Table III. No additional components were added to the liming. The masterbatch stage was mixed at 60 rpm with a starting mixer temperature of 100°C for 4.5 minutes or until the sample reached 170°C (whichever came first). The liming stage was mixed at 60 rpm with a starting mixer temperature of 100°C for 3.0 minutes or until the sample reached 170°C (whichever came first). The final stage was mixed at 40 rpm with a starting mixer temperature of 80°C for 2.5 minutes or until the sample reached 120°C (whichever came first).

[0134] [Table 3]

[0135] The vulcanizable compositions were subjected to Mooney analysis. These samples were cured at 145°C for 33 minutes. The bonded rubber was measured by GPC analysis as described above. Mechanical properties were measured according to ASTM D-412. Dynamic rheological properties were determined using both thermal analysis and strain sweep analysis, as shown in Table IV. The test results, as well as details of the rubber components, are shown in Table IV below.

[0136] [Table 4]

[0137] Various modifications and changes that do not depart from the scope and spirit of the present invention will be apparent to those skilled in the art. The present invention is not formally limited to the exemplary embodiments described herein. Furthermore, this application includes the following aspects: [Section 1] A vulcanizable rubber composition, (i)(a) natural rubber, (b) functionalized synthetic polyisoprene b, and (c) optionally butadiene-based synthetic rubber are rubber components, (ii) Silica filler and (iii) A vulcanizable rubber composition comprising a curing agent. [Section 2] The vulcanizable composition according to item 1, wherein the rubber components include natural rubber, functionalized synthetic polyisoprene, and butadiene-based synthetic rubber. [Section 3] The vulcanizable composition according to claim 1 or 2, wherein the vulcanizable composition comprises about 20 to about 90 weight percent of the rubber components based on the total weight of the vulcanizable rubber composition. [Section 4] The vulcanizable composition according to any one of claims 1 to 3, wherein the rubber component comprises about 40 to about 90 weight percent of the natural rubber based on the total weight of the rubber component. [Section 5] The vulcanizable composition according to any one of claims 1 to 4, wherein the rubber component comprises about 10 to about 40 weight percent of the functionalized synthetic polyisoprene based on the total weight of the rubber component. [Section 6] The vulcanizable composition according to any one of claims 1 to 5, wherein the rubber component comprises about 0 to about 40 weight percent of the butadiene-based synthetic rubber based on the total weight of the rubber component. [Section 7] The vulcanizable composition according to any one of claims 1 to 6, wherein the butadiene-based rubber is poly(butadiene), poly(styrene-co-butadiene), or a combination thereof. [Section 8] The vulcanizable composition according to any one of claims 1 to 7, wherein the butadiene rubber is a functionalized butadiene rubber. [Section 9] The butadiene-based rubber is a vulcanizable composition according to any one of claims 1 to 8, having a number-average molecular weight of more than 90 kg / mol. [Section 10] The functionalized synthetic polyisoprene is a vulcanizable composition according to any one of claims 1 to 9, comprising a silica interacting group. [Section 11] The functionalized synthetic polyisoprene is a vulcanizable composition according to any one of claims 1 to 10, comprising an alkoxysilane group. [Section 12] The functionalized synthetic polyisoprene is prepared from synthetic polyisoprene having a base number average molecular weight of about 100 to about 500 kg / mol, the vulcanizable composition according to any one of claims 1 to 11. [Section 13] The functionalized synthetic polyisoprene is prepared from synthetic polyisoprene having a base weight-average molecular weight of about 100 to about 600 kg / mol, the vulcanizable composition according to any one of claims 1 to 12. [Section 14] The aforementioned composition is a vulcanizable composition according to any one of claims 1 to 13, characterized by a t90 of more than 30 minutes. [Section 15] The vulcanizable composition according to any one of claims 1 to 14, comprising about 5 to about 80 parts by weight of silica filler per 100 parts by weight of the rubber component. [Section 16] The vulcanizing composition according to any one of claims 1 to 15, further comprising a silica coupling agent. [Section 17] A vulcanized product prepared from a vulcanizable composition described in any one of items 1 to 16. [Section 18] The vulcanized material described in subparagraph 17 is a component of a tire for a heavy vehicle. [Section 19] The vulcanized material according to item 17 or 18, wherein the vulcanized material is the tread or undertread of a tire for heavy vehicles. [Section 20] The vulcanizing agent described in any one of sub-sub [Section 21] The heavy vehicle tire is a vulcanized product according to any one of claims 17 to 20, having a diameter of at least 17.5 inches.

Claims

1. A vulcanizable rubber composition, (i) a rubber component comprising (a) natural rubber, (b) functionalized synthetic polyisoprene, and (c) optionally butadiene-based synthetic rubber, (ii) Silica filler and (iii) containing a hardening agent, The vulcanizable rubber composition comprises 20 to 90 weight percent of the rubber components based on the total weight of the vulcanizable rubber composition. The rubber component comprises, based on the total weight of the rubber component, 40 to 90 weight percent of the natural rubber, 12 to 40 weight percent of the functionalized synthetic polyisoprene, and 10 to 40 weight percent of the butadiene-based synthetic rubber. The butadiene-based synthetic rubber has a number-average molecular weight of more than 90 kg / mol, The functionalized synthetic polyisoprene is prepared from synthetic polyisoprene having a base number average molecular weight of 150 to 500 kg / mol and a base weight average molecular weight of 150 to 600 kg / mol. Vulcanizable rubber composition.

2. The aforementioned butadiene-based synthetic rubber is a functionalized butadiene-based rubber. The vulcanizable rubber composition according to claim 1.

3. The above composition is characterized by a t90 of more than 30 minutes. The vulcanizable rubber composition according to claim 1.

4. A vulcanized product prepared from the vulcanizable rubber composition described in claim 1, wherein the vulcanized product is a component of a tire for a heavy vehicle. vulcanizate.

Images