Modified diene copolymer having a target stabilized viscosity

Abstract

A process for preparing stabilized diene copolymers which are modified by reaction with imine group-containing hydrocarbyloxysilanes and subsequently stabilized with hydrocarbyloxysilanes.

Description

[Technical Field]

[0001] Embodiments of the present invention generally aim at modified diene copolymers having a target stabilized viscosity. In specific embodiments, the diene copolymer is modified by reaction with an imine group-containing hydrocarbyloxysilane and subsequently stabilized with the hydrocarbyloxysilane. [Background technology]

[0002] In the manufacture of tires, particularly tire treads, it is known that modified polymers, including those with end-functionalization, are used. It has been observed that rubber vulcanized products prepared using these modified polymers exhibit reduced hysteresis loss and a decrease in the Payne effect, which is the loss of mechanical energy due to the deaglomeration of fillers.

[0003] Polymer modification is often achieved by reacting living polymer species with compounds that can confer functional groups to the ends of polymer chains. For example, U.S. Patent No. 6,369,167 teaches the preparation of diene polymers, such as random copolymers of butadiene and styrene, by anionic polymerization techniques, and then the termination of the polymer with an imine-containing hydrocarbyloxysilane compound. The termination compound, also called a termination modifier, is used in an amount of 0.25 to 3 moles per mole of organolithium compound used to initiate anionic polymerization.

[0004] A similar end-modifier is disclosed in U.S. Patent No. 7,683,151, which teaches that at least 0.3 molar equivalents should be used based on the apparent active site. Following the denaturation reaction, this patent teaches that a condensation accelerator (e.g., tin carboxylate) is added to condense the hydrocarbyloxysilane residues at the polymer chain ends (to produce polymer coupling). After finishing, the resulting modified polymer has a Mooney viscosity of 10–150 (ML at 100°C). 1+4 ) has.

[0005] Hydrocarbyloxysilane residues have been found to increase Mooney viscosity after aging, and this increase is thought to be due to coupling between functional polymers in the presence of water. This coupling is thought to begin when water hydrolyzes the hydrocarbyloxysilane substituent to form a siloxy substituent, and then the siloxy substituents of each polymer condense and couple. U.S. Patent No. 6,255,404 teaches a countermeasure against this increase in Mooney viscosity by treating the modified polymer with an alkylalkoxysilane (e.g., octyltriethoxysilane) to stabilize the hydrocarbyloxysilane terminal group. Alkylalkoxysilanes may be added in amounts of 1 to 20 moles per mole of initiator, but if they are present in amounts exceeding the equivalent amount of alkoxysilane functional groups, a decrease in polymer viscosity is observed due to the plasticizing effect of the alkylalkoxysilane (i.e., excess alkylalkoxysilane acts as an oil). [Overview of the project]

[0006] One or more embodiments of the present invention are a process for preparing a stabilized diene copolymer having end modification, comprising: (i) combining an organolithium compound, a butadiene monomer, and a styrene monomer in a solvent with an optionally selected vinyl modifier to form a polymerization mixture; (ii) polymerizing the monomers to form a living polymer; and (iii) introducing an imine-containing hydrocarbyloxysilane compound into the polymerization mixture after the above step of polymerizing the monomers, wherein the imine-containing hydrocarbyloxysilane is added at a concentration of about 0.2 to 0.8 moles per mole of organolithium compound. The present invention provides a process comprising: (iv) introducing a modified polymer by adding it in a certain amount to form a polymerization mixture containing a modified polymer; (iv) after the above step of introducing an imine-containing hydrocarbyloxysilane, introducing the hydrocarbylhydrocarbyloxysilane into the polymerization mixture containing the modified polymer to form a stabilized polymerization mixture, wherein the hydrocarbylhydrocarbyloxysilane is added in an amount of about 1 to about 12 moles per mole of organolithium compound to form a stabilized polymerization mixture; and (v) desolventing the polymer mixture to provide a stabilized diene copolymer having terminal modification. [Modes for carrying out the invention]

[0007] Embodiments of the present invention are at least in part based on the discovery of a process for producing diene copolymers modified with an imine-containing hydrocarbyloxysilane compound and stabilized with a hydrocarbylhydrocarbyloxysilane compound. While the prior art has generally explored polymers of this nature, the present invention is based on the desire to achieve polymers having a relatively high initial viscosity (i.e., at the time of polymer desolvation) that allows for efficient handling during polymer production, and a relatively low post-aging viscosity (i.e., without significant Mooney increase) that allows for efficient use of the polymer in the production of rubber articles such as tires. In one or more embodiments, the diene copolymer produced according to the present invention is a modified copolymer of butadiene and styrene, with a Mooney viscosity greater than 50 (ML at 100°C) before isolation of the modified copolymer. 1+4 ) has an aging Mooney viscosity of less than 120 (ML at 100°C) 1+4 ) has. The prior art has explored diene copolymers terminated with imine-containing trialkoxysilanes, and the use of alkyltrioxysilanes to stabilize similar polymers against excessive Mooney growth. However, the prior art does not understand all the factors that significantly affect important polymer properties such as Mooney viscosity, and the interactions between these factors. In particular, it was unexpectedly found that the viscosity of the polymer (i.e., Mooney viscosity) depends on factors such as peak molecular weight, amount of modifier, amount of stabilizer, coupling efficiency, and amount of condensation catalyst, from initial synthesis through long-term aging. These findings make it possible to obtain copolymers that have relatively high Mooney viscosity upon polymer desolvation while maintaining relatively low Mooney viscosity after aging. Process Overview

[0008] In one or more embodiments, the process for forming a polymer according to the present invention generally includes (i) a polymerization step for forming a reactive polymer, (ii) a modification step for functionalizing the reactive polymer, (iii) a stabilization step for stabilizing the functionalized polymer, and (iv) a polymer desolvation step for isolating the stabilized functionalized polymer. In one or more embodiments, the process may further include a hydrolysis and / or condensation step. In these or other embodiments, the process may further include a polymer drying step for removing water from the polymer product.

[0009] polymerization In one or more embodiments, the polymerization step includes anionic polymerization of a conjugated diene monomer (e.g., butadiene) and a vinyl aromatic monomer (e.g., styrene) in solution to provide a polymerization mixture containing a polymer having reactive polymer chain ends.

[0010] The preparation of polymers using anionic polymerization techniques is generally known. The important mechanistic features of anionic polymerization are described in books (e.g., Hsieh, HL; Quirk, RPA Anionic Polymerization: Principles and Practical Applications; Marcel Dekker: New York, 1996) and reviews (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.

[0011] Monomers that can be anionic polymerized to form these polymers include conjugated diene monomers, which can optionally be copolymerized with other monomers such as vinyl-substituted aromatic monomers. Examples of conjugated diene monomers include 1,3-butadiene, isoprene, 1,3-pentadiene, 1,3-hexadiene, 2,3-dimethyl-1,3-butadiene, 2-ethyl-1,3-butadiene, 2-methyl-1,3-pentadiene, 3-methyl-1,3-pentadiene, 4-methyl-1,3-pentadiene, and 2,4-hexadiene. A mixture of two or more conjugated dienes may be used in the copolymerization. Examples of monomers copolymerizable with conjugated diene monomers include vinyl-substituted aromatic compounds such as styrene, p-methylstyrene, α-methylstyrene, and vinylnaphthalene.

[0012] The implementation of the present invention is not limited by selecting any particular anionic initiator. Exemplary anionic initiators include organolithium compounds. In one or more embodiments, the organolithium compound may contain heteroatoms. 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. Still other anionic initiators include organosodium compounds such as phenylsodium and 2,4,6-trimethylphenylsodium.

[0013] Anionic polymerization may be carried out in polar solvents, nonpolar solvents, and mixtures thereof. In one or more embodiments, the solvent may be used as a carrier to dissolve or suspend the initiator to facilitate delivery of the initiator to the polymerization system.

[0014] In one or more embodiments, suitable solvents include organic compounds that do not undergo or incorporate polymerization into the propagating polymer chains during the polymerization of monomers in the presence of a catalyst. In one or more embodiments, these organic species are liquids at ambient temperature and pressure. In one or more embodiments, these organic solvents are inert to the catalyst. Exemplary organic solvents include hydrocarbons having low or relatively low boiling points, such as aromatic hydrocarbons, aliphatic hydrocarbons, and cycloaliphatic 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 spirit. Also, non-limiting examples of cycloaliphatic hydrocarbons include cyclopentane, cyclohexane, methylcyclopentane, and methylcyclohexane. Mixtures of the above hydrocarbons can also be used. Low-boiling hydrocarbon solvents are typically separated from the polymer upon completion of the polymerization. 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-extended polymers. Since these hydrocarbons are non-volatile, they typically do not need to be separated and remain incorporated within the polymer.

[0015] Anionic polymerization may be carried out in the presence of a randomizer (sometimes referred to as a polarity coordinator) or a vinyl modifier. As will be understood by those skilled in the art, these compounds, which can play a dual role, can assist in the randomization of comonomers throughout the polymer chain and / or can adjust the vinyl content of mer units derived from the diene. Compounds useful as randomizers include those having an oxygen or nitrogen heteroatom and an unbonded electron pair. Examples include linear and cyclic oligomeric oxolanyl alkanes; dialkyl ethers (also known as grim ethers) of mono and oligoalkylene glycols; "crown" ethers; tertiary amines; linear THF oligomers; and the like. Linear and cyclic oligomeric oxolanyl alkanes are described in U.S. Patents 4,429,091 and 9,868,795, which are incorporated herein by reference. Specific examples of compounds useful as randomizers include 2,2-bis(2'-tetrahydrofuryl)propane, 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. In other embodiments, potassium alkoxides may be used to randomize the styrene distribution.

[0016] The amount of randomizer to be used may depend on various factors (e.g., the desired polymer microstructure, monomer-to-comonomer ratio, polymerization temperature, and the properties of the specific randomizer used). In one or more embodiments, the amount of randomizer used may be in the range of 0.01 to 100 moles per mole of anionic initiator.

[0017] Anionic initiators and randomizers can be introduced into the polymerization system by various methods. In one or more embodiments, the anionic initiator and randomizer may be added separately to the monomer to be polymerized, either in a stepwise manner or simultaneously.

[0018] As described above, reactive polymers are produced by polymerizing conjugated diene monomers together with monomers copolymerizable with them, in the presence of an effective amount of initiator. The introduction of the initiator, conjugated diene monomer, comonomer, and solvent forms a polymerization mixture, within which the reactive polymer is formed. Polymerization in a solvent produces a polymerization mixture in which the polymer product is dissolved or suspended in the solvent. This polymerization mixture is sometimes referred to as polymer cement.

[0019] The amount of initiator to be 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 polymerization conversion rate, the desired molecular weight, and many other factors). In one or more embodiments, the amount of initiator used may be expressed as millimoles of initiator per unit weight of monomer. In one or more embodiments, the initiator load may vary from about 0.05 to about 50 millimoles per 100 grams of monomer, from about 0.1 to about 25 millimoles in other embodiments, from about 0.2 to about 2.5 millimoles in yet another embodiment, and from about 0.4 to about 0.7 millimoles in yet another embodiment.

[0020] In one or more embodiments, polymerization may be carried out in any conventional polymerization vessel known in the art. For example, polymerization may be carried out in a conventional stirred-tank reactor. In one or more embodiments, all the components used for polymerization may be combined in a single vessel (e.g., a conventional stirred-tank reactor), and all steps of the polymerization process may be carried out in this vessel. In other embodiments, two or more components may be combined in one vessel beforehand and then transferred to another vessel where the monomer (or at least most of it) is polymerized. Since various embodiments of the present invention involve the use of multiple reactors or reaction zones, the vessel in which polymerization takes place (e.g., a tank reactor) may be referred to as the first vessel or first reaction zone.

[0021] 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 may be controlled to maintain the temperature of the polymerization mixture within 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 a pressure 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. Polymer properties before modification

[0022] As described above, in certain embodiments of the present invention, the reactive polymer produced is a copolymer of styrene and butadiene. In one or more embodiments, the copolymer is random and optionally contains microblocks of styrene or butadiene (i.e., 3 to 10 repeating units of styrene or butadiene). In one or more embodiments, the copolymer does not contain or substantially contains chemical blocks of styrene or butadiene (i.e., more than 10 repeating units of styrene or butadiene). In one or more embodiments, the reactive copolymer can be characterized by a styrene content which is a weight percentage of styrene monomer units relative to the total weight of the reactive copolymer before modification. As will be understood by those skilled in the art, this can be determined from the weight of the input styrene monomer relative to the total weight of the input monomers (i.e., the total weight of the input butadiene and styrene). In one or more embodiments, the reactive polymer contains more than 5 weight percent of styrene, more than 7 weight percent in other embodiments, and more than 9 weight percent in other embodiments, before modification. In these or other embodiments, the reactive polymer contains less than 45 weight percent, less than 30 weight percent in other embodiments, less than 16 weight percent in other embodiments, less than 14 weight percent in other embodiments, and less than 12 weight percent in other embodiments. In one or more embodiments, the polymer contains about 5 to about 45 weight percent, about 7 to about 14 weight percent in other embodiments, and about 9 to about 12 weight percent in other embodiments.

[0023] In one or more embodiments, the reactive polymer produced according to the embodiments of the present invention can be characterized by its vinyl content, which can be described as the number of unsaturated 1,2 microstructures 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 FTIR analysis. In one or more embodiments, the reactive polymer contains more than 10% by weight of vinyl, in other embodiments more than 20% by weight of vinyl, and in other embodiments more than 35% by weight of vinyl. In these or other embodiments, the reactive polymer contains less than 80% by weight of vinyl, in other embodiments less than 60% by weight of vinyl, and in other embodiments less than 46% by weight of vinyl. In one or more embodiments, the reactive polymer contains about 10 to about 80% of vinyl, in other embodiments about 20 to about 60% of vinyl, and in other embodiments about 35 to about 46% of vinyl.

[0024] In one or more embodiments, the reactive polymer can also be characterized by its peak molecular weight (Mp). As will be understood by those skilled in the art, Mp can be determined by using gel permeation chromatography (GPC) with appropriate calibration standards. For the purposes of this specification, GPC measurements use polystyrene standards and polystyrene Mark-Fwink constants unless otherwise specified. In one or more embodiments, the reactive polymer has an Mp greater than 160 kg / mol, greater than 170 kg / mol in other embodiments, greater than 180 kg / mol in other embodiments, which may also be referred to as the base Mp. In these or other embodiments, the reactive polymer has an Mp less than 280 kg / mol, less than 260 kg / mol in other embodiments, less than 250 kg / mol in other embodiments. In one or more embodiments, the reactive polymer has an Mp of about 160 to about 280 kg / mol, about 170 to about 260 kg / mol in other embodiments, and about 180 to about 250 kg / mol in other embodiments.

[0025] In one or more embodiments, at least about 30% of the polymer molecules contain living ends; in other embodiments, at least about 50% of the polymer molecules contain living ends; and in other embodiments, at least about 80% contain living ends. Polymer modification

[0026] As described above, after polymerization, the reactive polymer undergoes modification. That is, the reactive ends of the polymer are modified by introducing an imine-containing hydrocarbyloxysilane compound into the polymerization mixture, which is sometimes referred to as functionalization. The polymer chain ends are thought to react with the imine-containing hydrocarbyloxysilane (which may be referred to as a functionalizing agent or modifying agent for the purposes of this specification) to provide functionalizing agent residues to the polymer chain ends. Therefore, the reaction between the polymer and the functionalizing agent produces a polymer composition containing one or more polymer chains containing end groups derived from the imine-containing hydrocarbyloxysilane. In one or more embodiments, more than 10 mol% of the polymer chains in the polymer composition contain end functional groups, in other embodiments more than 30 mol%, and in other embodiments more than 35 mol%. In these or other embodiments, less than 80 mol%, in other embodiments less than 70 mol%, and in other embodiments less than 65 mol% of the polymer chains in the polymer composition contain end functional groups. In one or more embodiments, about 10 to about 80 mol% of the polymer chains in the polymer composition contain terminal functional groups, in other embodiments about 30 to about 70 mol%, and in other embodiments about 35 to about 65 mol%. These polymers may also be referred to as functionalized polymers or modified polymers. It should be understood that polymer coupling may also occur from reactions between functionalizing agents and reactive polymers. In any case, polymers having chain-terminal functional groups and polymers coupled with residues of functionalizing agents are both referred to as modified polymers or functionalized polymers unless otherwise specified.

[0027] In one or more embodiments, the imine-containing hydrocarbyloxysilane may be N-(1,3-dimethylbutylidene)-3-(triethoxysilyl)-1-propanamine, N-(1-methylethylidene)-3-(triethoxysilyl)-1-propanamine, N-ethylidene-3-(triethoxysilyl)-1-propanamine, N-(1-methylpropylidene)-3-(triethoxysilyl)-1-propanamine, or N-(4-N,N-dimethylaminobenzylidene)-3-(triethoxysilyl)-1-propanamine. In a particular embodiment, the imine-containing hydrocarbyloxysilane is N-(1-methylpropylidene)-3-(triethoxysilyl)-1-propanamine or N-(1,3-dimethylbutylidene)-3-(triethoxysilyl)-1-propanamine.

[0028] The amount of functionalizing agent (i.e., imine-containing hydrocarbyloxysilane) used in the implementation of the present invention can be described with respect to lithium or metal cations related to the initiator. In one or more embodiments, the amount of functionalizing agent introduced into the polymerization mixture is more than 0.2 moles per mole of lithium in the initiator, more than 0.3 moles in other embodiments, and more than 0.4 moles in other embodiments. In these or other embodiments, less than 0.8 moles per mole of lithium, less than 0.7 moles in other embodiments, and less than 0.65 moles in other embodiments are introduced into the polymerization mixture. In one or more embodiments, about 0.2 to about 0.8 moles per mole of lithium, about 0.3 to about 0.7 moles in other embodiments, and about 0.4 to about 0.65 moles in other embodiments are introduced into the polymerization mixture.

[0029] In one or more embodiments, a functionalizing agent is introduced into the polymer cement while the polymer is dissolved or suspended in the solvent. As those skilled in the art will understand, this solution may also be referred to as polymer cement. In one or more embodiments, the characteristics of the polymer cement, such as its concentration, are the same as or similar to those of the cement before functionalization. In other embodiments, a stabilizer may be introduced into the polymer while the polymer is suspended or dissolved in the monomer.

[0030] In one or more embodiments, the modification of the polymer (i.e., the introduction of a functionalizing agent into the polymer cement) is carried out in the same vessel in which polymerization takes place. In other embodiments, the modification of the polymer is carried out outside the reaction vessel in which polymerization takes place. For example, the functionalizing agent can be introduced into the polymerization mixture (i.e., the polymer cement) in a downstream vessel or downstream transfer conduit.

[0031] In one or more embodiments, the reaction between the functionalizing agent and the reactive polymer may occur at a temperature of about 10°C to about 150°C, and in other embodiments, about 20°C to about 110°C. The time required for the reaction between the functionalizing agent and the reactive polymer to complete 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 30 seconds to about 90 minutes, or in other embodiments, 10 to 60 minutes. Polymer stabilization

[0032] As described above, the modified polymer is stabilized after modification. Specifically, the modified polymer is stabilized by introducing alkylhydrocarbyloxysilane into the polymerization mixture containing the modified polymer. The alkylhydrocarbyloxysilane is thought to react with the terminal functional groups. Furthermore, the reaction between the chain terminal functional groups and the alkylhydrocarbyloxysilane is thought to occur during the introduction of the two molecules or after aging of the composition. The reaction between the alkylhydrocarbyloxysilane and the terminal groups produces a polymer composition containing one or more polymer chains, including terminal groups derived from the reaction between imine-containing hydrocarbyloxysilane and the subsequent alkylhydrocarbyloxysilane.

[0033] In one or more embodiments, the stabilizer is a hydrocarbylhydrocarbyloxysilane, which can be defined by formula I: [ka] (In the formula, R2 is a hydrocarbyl group, R 3 , R 4 , and R 5 are each independently a hydrocarbyl group or a hydrocarbyloxy group). In certain embodiments, R 3 , R 4 , and R 5 are hydrocarbyl groups. In other embodiments, R 3 and R 4 are hydrocarbyl groups and R 5 is a hydrocarbyloxy group. In other embodiments, R 3 is a hydrocarbyl group and R 4 and R 5 are hydrocarbyloxy groups. In certain embodiments, R 3 , R 4 , and R 5 are all hydrocarbyloxy groups.

[0034] In one or more embodiments, examples of the hydrocarbyl group of the hydrocarbyl hydrocarbyloxy silane include, but are not limited to, an alkyl group, a cycloalkyl group, a substituted cycloalkyl group, an alkenyl group, a cycloalkenyl group, a substituted cycloalkenyl group, an aryl group, an allyl group, a substituted aryl group, an aralkyl group, an alkaryl group, or an alkynyl group. A substituted hydrocarbyl group includes a hydrocarbyl group in which one or more hydrogen atoms are replaced with a substituent such as an alkyl group. In one or more embodiments, the hydrocarbyl group may contain from one or the minimum number of carbon atoms appropriate to form a group up to 20 carbon atoms. These hydrocarbyl groups may contain heteroatoms such as, but not limited to, nitrogen, boron, oxygen, silicon, sulfur, and phosphorus atoms.

[0035] In one or more embodiments, the hydrocarbyloxy group of hydrocarbylhydrocarbyloxysilane may include, but is not limited to, an alkoxy group, a cycloalkoxy group, a substituted cycloalkoxy group, an alkenyloxy group, a cycloalkenyloxy group, a substituted cycloalkenyloxy group, an aryloxy group, an allyloxy group, a substituted aryloxy group, an aralkyloxy group, an alkaryloxy group, or an alkynyloxy group. Examples of substituted hydrocarbyloxy groups include hydrocarbyloxy groups in which one or more hydrogen atoms bonded to a carbon atom are replaced by substituents such as alkyl groups. In one or more embodiments, the hydrocarbyloxy group may contain one or a minimum number of carbon atoms appropriate for forming the group, up to 20 carbon atoms. The hydrocarbyloxy group may contain heteroatoms such as, but is not limited to, nitrogen, boron, oxygen, silicon, sulfur, and phosphorus atoms.

[0036] In one or more embodiments, the types of hydrocarbylhydrocarbyloxysilane include trihydrocarbylhydrocarbyloxysilane, dihydrocarbyldihydrocarbyloxysilane, hydrocarbyltrihydrocarbyloxysilane, and tetrahydrocarbyloxysilane.

[0037] Specific examples of hydrocarbylhydrocarbyloxysilanes include methyltrimethoxysilane, ethyltrimethoxysilane, propyltrimethoxysilane, phenyltrimethoxysilane, octyltrimethoxysilane, decyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, propyltriethoxysilane, phenyltriethoxysilane, octyltriethoxysilane, decyltriethoxysilane, methyltriphenoxysilane, ethyltriphenoxysilane, propyltriphenoxysilane, octyltriphenoxysilane, Phenyltriphenoxysilane, decyltriphenoxysilane, methyldiethoxymethoxysilane, ethyldiethoxymethoxysilane, propyldiethoxymethoxysilane, phenyldiethoxymethoxysilane, octyldiethoxymethoxysilane, decyldiethoxymethoxysilane, methyldiphenoxymethoxysilane, ethyldiphenoxymethoxysilane, propyldiphenoxymethoxysilane, phenyldiphenoxymethoxysilane, octyldiphenoxymethoxysilane, decyldiphenoxymethoxysilane, methyldimethoxyethoxysilane, Tyl dimethoxyethoxysilane, propyl dimethoxyethoxysilane, phenyl dimethoxyethoxysilane, octyl dimethoxyethoxysilane, decyl dimethoxyethoxysilane, methyl diphenoxyethoxysilane, ethyl diphenoxyethoxysilane, propyl diphenoxyethoxysilane, phenyl diphenoxyethoxysilane, octyl diphenoxyethoxysilane, decyl diphenoxyethoxysilane, methyl dimethoxyphenoxysilane, ethyl dimethoxyphenoxysilane, propyl dimethoxyphenoxysilane, phenyl dimethoxyethoxy Noxysilane, octyl dimethoxyphenoxysilane, decyl dimethoxyphenoxysilane, methyl diethoxyphenoxysilane, ethyl diethoxyphenoxysilane, propyl diethoxyphenoxysilane, phenyl diethoxyphenoxysilane, octyl diethoxyphenoxysilane, decyl diethoxyphenoxysilane, methyl methoxyethoxyphenoxysilane, ethyl methoxyethoxyphenoxysilane, propyl methoxyethoxyphenoxysilane, phenyl methoxyethoxyphenoxysilane, octyl methoxyethoxyphenoxysilane,And decylmethoxyethoxyphenoxysilane is another example.

[0038] In one or more embodiments, a stabilizer is added to the polymer cement after sufficient time has been provided for the reaction between the reactive polymer and the functionalizing agent to complete. In one or more embodiments, the stabilizer is introduced to the polymer cement 30 minutes after the time the functionalizing agent was introduced to the polymer cement, 15 minutes after in other embodiments, and 10 minutes after in other embodiments.

[0039] The amount of stabilizer (i.e., hydrocarbylhydrocarbyloxysilane) used in the implementation of the present invention can be described in relation to the number of moles of lithium related to the initiator. In one or more embodiments, more than 1 mole of functionalizing agent is introduced into the polymerization mixture per mole of lithium in the initiator, in other embodiments more than 2 moles, in other embodiments more than 3 moles, and in other embodiments more than 4 moles. In these or other embodiments, less than 12 moles of functionalizing agent is introduced into the polymerization mixture per mole of lithium, in other embodiments less than 11 moles, in other embodiments less than 10 moles, in other embodiments less than 9 moles, and in other embodiments less than 8 moles. In one or more embodiments, about 1 to about 12 moles of functionalizing agent are introduced into the polymerization mixture per mole of lithium, in other embodiments about 3 to about 10 moles, and in other embodiments about 4 to about 8 moles.

[0040] In one or more embodiments, polymer stabilization (i.e., introduction of a stabilizer) is carried out in the same vessel in which polymerization takes place. In these embodiments, this includes the same vessel in which modification takes place. In other embodiments, polymer stabilization (i.e., introduction of a stabilizer) is carried out outside the vessel in which polymerization takes place. Similarly, in one or more embodiments, polymer stabilization is carried out outside the vessel in which polymer modification takes place. For example, in one or more embodiments, a stabilizer can be added to the polymerization mixture (i.e., polymer cement) in a vessel or transfer line that is downstream of the vessel in which polymerization takes place and downstream of the vessel in which polymer modification takes place. For the purposes of this specification, the vessel or conduit in which the stabilizer is introduced relative to the polymerization vessel may also be referred to as a second vessel or second reaction zone. Condensation accelerator

[0041] In one or more embodiments, after introducing a functionalizing agent to the reactive polymer, a condensation accelerator may be added to the polymerization mixture optionally after a quenching agent and / or antioxidant, optionally after or together with a stabilizer, or optionally after recovery or isolation 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 (U.S. Patent No. 7,683,151), which is incorporated herein by reference. In other embodiments, organic acids can be used as condensation accelerators. Useful types of organic acids include aliphatic, alicyclic, and aromatic monocarboxylic acids, dicarboxylic acids, tricarboxylic acids, and tetracarboxylic acids. Specific examples of useful organic acids include, but are not limited to, acetic acid, propionic acid, but but but also include, hexanoic acid, 2-methylhexanoic acid, 2-ethylhexanoic acid, cyclohexanoic acid, and benzoic acid.

[0042] The amount of condensation accelerator used in the implementation of the present invention can be described in relation to the number of moles of lithium related to the initiator. In one or more embodiments, the amount of condensation accelerator per mole of lithium is more than 1.0 mole per mole of lithium in the initiator, more than 1.5 moles in other embodiments, and more than 1.8 moles in other embodiments. In these or other embodiments, less than 4.0 moles per mole of lithium, less than 3.3 moles in other embodiments, and less than 3.0 moles in other embodiments are introduced into the polymerization mixture. In one or more embodiments, about 1.0 to about 4.0 moles per mole of lithium, about 1.5 to about 3.3 moles in other embodiments, and about 1.8 to about 3.0 moles in other embodiments are introduced into the polymerization mixture. Antioxidants

[0043] In one or more embodiments, after introducing a functionalizing agent to the reactive polymer, an antioxidant may be optionally added after a quenching agent and / or antioxidant, optionally after or together with a stabilizer, or optionally after recovery or isolation of the functionalized polymer, to the polymerization mixture. An exemplary antioxidant is 2,6-di-tert-butyl-4-methylphenol.

[0044] 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. Optional quenching

[0045] In one or more embodiments, a quenching agent may be added to the polymerization mixture to inactivate any remaining reactive polymer chains and catalyst or catalytic components after the reaction between the reactive polymer and the functionalizing agent has been achieved or completed. Examples of quenching agents include, but are not limited to, protic compounds, including alcohols, carboxylic acids, inorganic acids, water, or mixtures thereof. The amount of quenching agent used may be in the range of 0.5 to 10 moles of quenching agent per mole of lithium used to initiate polymerization. Polymer properties during desolvation

[0046] As described above, the polymer of the present invention, in a desolvation step as described below herein, has a Mooney viscosity (ML at 100°C) greater than 50, greater than 52 in other embodiments, and greater than 55 in other embodiments. 1+4 The polymer of the present invention is characterized by having a Mooney viscosity (ML at 100°C) of about 50 to about 105 in the desolvent step, about 52 to about 80 in other embodiments, and about 55 to about 70 in other embodiments. 1+4 ) is characterized by. For the purposes of this specification, unless otherwise specified, Mooney viscosity (ML at 100°C) 1+4 ) is determined according to ASTMD 1648-17.

[0047] In addition, in one or more embodiments, the polymers of the present invention are characterized by a coupling rate of more than 20 percent in the desolvation step, more than 30 percent in other embodiments, and more than 40 percent in other embodiments. In these or other embodiments, the polymers of the present invention are characterized by a coupling rate of less than 80 percent in the desolvation step, less than 70 percent in other embodiments, and less than 65 percent in other embodiments. In one or more embodiments, the polymers of the present invention are characterized by a coupling rate of about 20 to about 80 percent in the desolvation step, about 30 to about 70 percent in other embodiments, and about 40 to about 65 percent in other embodiments. As will be understood by those skilled in the art, the coupling rate can be determined by GPC. For the purposes of this specification, coupling refers to the area ratio of the GPC curve having two or more peaks than the base peak (i.e., the coupling rate is B / (A+B)·100% (wherein A is the area of ​​the base peak and B is the total area of ​​all peaks that are two or more than the base peak (i.e., A))).

[0048] In one or more embodiments, the method of the present invention comprises selecting from the scope disclosed herein (i) the peak molecular weight of a base polymer, (ii) a desired load of a functionalizing agent, and (iii) a suitable load of a stabilizer, and (iv) a suitable load of a condensation catalyst to satisfy a target Mooney viscosity (e.g., greater than 50) during desolvation within the range of the following formulas: Mooney viscosity after solvent removal = 44.7 + [0.5218 base Mp] - [5.1 equivalent of functionalizing agent] - [4.765 equivalent of stabilizer] + [8.86 equivalent of condensation accelerator] (In the formula, Mooney viscosity during solvent removal is given by ML at 100°C during solvent removal.) 1+4 (where Base Mp represents the peak molecular weight (kg / mol) of the base polymer as determined by GPC using polystyrene standards and the polystyrene Mark-Fwink constant, the functionalizer equivalent is the number of moles of functionalizer per mole of lithium used to initiate polymerization of the polymer, the stabilizer equivalent is the number of moles of stabilizer per mole of lithium used to stabilize the polymer, and the condensation accelerator equivalent is the number of moles of condensation catalyst per mole of lithium used to promote condensation).

[0049] In one or more embodiments, the above formula satisfies the Mooney viscosity upon desolvation when the Mooney viscosity is 50 or greater (or within other ranges disclosed herein), Mp is about 160 to about 180 kg / mol, the functionalizing agent equivalent is about 0.2 to about 0.8 moles of functionalizing agent per mole of lithium, the stabilizer equivalent is about 1 to about 12 moles of stabilizer per mole of lithium, and the condensation accelerator equivalent is about 1 to about 4 moles per mole of lithium. As will be understood by those skilled in the art, the above formula may also be satisfied within other ranges disclosed herein (e.g., other ranges of functionalizing agent equivalents). Desolvation of polymers

[0050] As described above, after stabilization, and optionally after the introduction of a condensation accelerator and / or antioxidant, the polymer product (i.e., the stabilized functionalized polymer) undergoes desolvation. In other words, as described above, the polymer is synthesized in an organic solvent, and during the desolvation step, the organic solvent is separated from the polymer.

[0051] In certain embodiments, desolvation includes hot water and / or vapor coagulation. For example, a polymerization mixture containing a stabilized modified polymer may be combined with a vapor or hot water stream. The heat associated with the vapor or hot water stream volatilizes the solvent and any unreacted monomers. The polymer product is then dispersed in the aqueous phase, for example, in the form of polymer crumbs. The properties and size of the polymer crumbs can generally be manipulated by introducing mechanical energy in the form of a mixer.

[0052] In one or more embodiments, the polymer crumbs are temporarily stored in water as a crumb dispersion until the subsequent drying steps described below. The crumb dispersion is generally a mixture of polymer particles or crumbs and water. The polymer particles, sometimes referred to as coagulated polymers, are generally macroscale and have dimensions of at least 1 mm or more. This crumb dispersion can be contained in a tank, such as a conventional reactor tank, such as a continuous stirred-tank reactor.

[0053] In one or more embodiments, the polymer crumb can be further processed to remove residual solvent and dry the polymer (i.e., separate the polymer from water). In the embodiment of the present invention, the polymer can be dried using prior art, which may include one or more of filtration, pressing, and heating. After desolvent removal and drying, the volatile content of the dry polymer may be less than 2.0% by weight of the polymer, less than 1.0% by weight in other embodiments, and less than 0.5% by weight in other embodiments.

[0054] In other embodiments, the polymer product can be desolvated by using a devolatilizer, which is an extruder-type device that can operate in conjunction with heat and / or vacuum. In yet another embodiment, the polymerization mixture may be directly drum-dried.

[0055] Regardless of the method used to desolvate and dry the polymer, the finished polymer product is sometimes referred to as a dry polymer. Using conventional techniques, the dry polymer can be molded or otherwise manipulated to form a bale. Polymer properties of dry polymers

[0056] In one or more embodiments, the dried, unaged polymer of the present invention has an advantageous Mooney viscosity (ML at 100°C). 1+4 ) is characterized by. Specifically, in one or more embodiments, the polymer has a Mooney viscosity (ML at 100°C) of less than 95 within 24 hours of desolventing and drying, less than 90 in other embodiments, and less than 85 in other embodiments. 1+4 ) has. In these or other embodiments, the polymer has a Mooney viscosity (ML at 100°C) of about 35 to about 120, in other embodiments about 55 to about 95, in other embodiments about 60 to about 90, and in other embodiments about 65 to about 85 within 24 hours of desolvation and drying. 1+4 ) has the dry, unaged Mooney viscosity (ML at 100°C). For the purposes of this specification, 1+4 This is sometimes referred to as the Mooney viscosity of veil. Polymer properties of polymers after aging

[0057] As described above, the polymer of the present invention has an advantageous Mooney viscosity (ML at 100°C) after aging. 1+4 ) is characterized by. Specifically, in one or more embodiments, the polymer has a Mooney viscosity (ML at 100°C) of less than 120 after desolvent removal and drying and aging for two years, less than 105 in other embodiments, and less than 95 in other embodiments. 1+4 ) has. In one or more embodiments, the polymer has a Mooney viscosity (ML at 100°C) of about 70 to about 120, in other embodiments about 80 to about 105, and in other embodiments about 85 to about 95 when aged for two years after desolvent removal and drying. 1+4) has. Specifically for the purposes of this specification, with respect to Mooney viscosity after 2 years of aging, accelerated aging may be performed at 100°C for 2 days instead of 2 years of room temperature aging. In other words, for the purposes of this specification, the two aging methods are treated equally with respect to the resulting viscosity.

[0058] In one or more embodiments, the method of the present invention comprises selecting from the scope disclosed herein (i) the peak molecular weight of a base polymer, (ii) a desired load of a functionalizing agent, and (iii) an appropriate load of a stabilizer to satisfy a target post-aging Mooney viscosity (e.g., less than 120) within the range of the following formulas: Mooney viscosity after aging = -34.2 + [Mooney viscosity of 0.828 bales] + [0.348 base Mp] - [0.425% coupling %] + [98.9 equivalent of functionalizer] - [6.16 equivalent of stabilizer] (In the formula, aged Mooney is ML at 100°C after heating and aging at 100°C for 48 hours) 1+4 The Mooney viscosity of the bale is ML at 100°C within 24 hours of solvent removal and drying. 1+4 (where Base Mp represents the peak molecular weight (kg / mol) of the base polymer as determined by GPC using polystyrene standards and polystyrene Mark-Fwink constants, Coupling % is the percentage of coupling polymer after desolvation as determined by GPC, Functionalizer equivalent is the number of moles of functionalizer per mole of lithium used to initiate polymerization of the polymer, and Stabilizer equivalent is the number of moles of stabilizer per mole of lithium used to stabilize the polymer).

[0059] In one or more embodiments, the Mooney viscosity is 120 or less (or other ranges disclosed herein), and the Mooney viscosity of the bale is about 35 to about 12 0The above formula is satisfied for Mooney after aging if Mp is approximately 160 to approximately 180 kg / mol, coupling % is approximately 20% to approximately 80%, the functionalizing agent equivalent is approximately 0.2 to approximately 0.8 moles of functionalizing agent per mole of lithium, and the stabilizer equivalent is approximately 1 to approximately 12 moles of stabilizer per mole of lithium. As will be understood by those skilled in the art, the above formula may also be satisfied in other ranges disclosed herein (e.g., other ranges of functionalizing agent equivalents). Industrial applicability

[0060] The polymer of the present invention is particularly useful in preparing rubber compositions that can be used in the manufacture of tire components. The rubber compounding technology and the additives used therein are generally related to The Compounding and Vulcanization of Rubber, in Rubber Technology (2 nd This is disclosed in Ed. 1973.

[0061] Rubber compositions can be prepared by using the polymer of the present invention alone or in combination with other elastomers (i.e., polymers that can be vulcanized to form compositions having rubber or elastomer properties). Other elastomers that may be used include natural and synthetic rubbers. Synthetic rubbers are typically obtained from polymerization of conjugated diene monomers, copolymerization of conjugated diene monomers with other monomers (e.g., vinyl-substituted aromatic monomers), or copolymerization of ethylene with one or more α-olefins and optionally one or more diene monomers.

[0062] Exemplary elastomers include natural rubber, synthetic polyisoprene, polybutadiene, polyisobutylene-co-isoprene, neoprene, poly(ethylene-co-propylene), poly(styrene-co-butadiene), poly(styrene-co-isoprene), poly(styrene-co-isoprene-co-butadiene), poly(isoprene-co-butadiene), poly(ethylene-co-propylene-co-diene), polysulfide rubber, acrylic rubber, urethane rubber, silicone rubber, epichlorohydrin rubber, and mixtures thereof. These elastomers can have countless macromolecular structures, such as linear, branched, and star-shaped structures.

[0063] The rubber composition may contain fillers, such as inorganic and organic fillers. Examples of organic fillers include carbon black and starch. Examples of inorganic fillers include silica, aluminum hydroxide, magnesium hydroxide, mica, talc (hydrated magnesium silicate), and clay (hydrated aluminum silicate). Carbon black and silica are the most common fillers used in tire manufacturing. In some embodiments, mixtures of different fillers may be used advantageously.

[0064] In one or more embodiments, carbon blacks include furnace black, channel black, and lamp black. More specific examples of carbon blacks include ultra-abrasive furnace black, intermediate ultra-abrasive furnace black, high abrasion 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.

[0065] In certain embodiments, the surface area (EMSA) of the carbon black is at least 20 m². 2 / g, in other embodiments at least 35m 2The value may be / g, and the surface area value can be determined using cetyltrimethylammonium bromide (CTAB) technology according to ASTM standard D-1765. The carbon black may be in pelletized or unpelletized cotton form. The preferred form of carbon black may depend on the type of mixing equipment used to mix the rubber compound.

[0066] The amount of carbon black used in the rubber composition may be up to about 50 parts by weight per 100 parts by weight (phr) of rubber, and is typically about 5 to about 40 parts by weight.

[0067] Some commercially available silica products that can be used include Hi-Sil® 215, Hi-Sil® 233, and Hi-Sil® 190 (PPG Industries, Inc.; Pittsburgh, Pa.). Other suppliers of commercially available silica include Grace Davison (Baltimore, Md.), Degussa Corp. (Parsippany, NJ), Rhodia Silica Systems (Cranbury, NJ), and JMHuber Corp. (Edison, NJ).

[0068] In one or more embodiments, silica can be characterized by its surface area, which serves as a measure of its reinforcing properties. The Brunauer, Emmett, and Teller ("BET") method (described in J.Am.Chem.Soc., 1939, vol.60, 2 pp.309-319) is an accepted 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, about 150~220m 2 / g is one example.

[0069] The pH of silica is generally about 5 to about 7, or slightly higher than 7, or in other embodiments, about 5.5 to about 6.8.

[0070] 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 disclosed below: 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 5,68 Nos. 4,171, 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 are incorporated herein by reference.

[0071] The amount of silica used in the rubber composition may be about 1 to about 100 phr, or in other embodiments, about 5 to about 80 phr. The useful upper limit is limited by the high viscosity provided by the silica. When silica is used with carbon black, the amount of silica can be reduced to about 1 phr. Because the amount of silica is low, the amount of coupling agent and shielding agent used can be reduced. Generally, the amount of coupling agent and shielding agent is in the range of about 4% to about 20% by weight, based on the weight of silica used.

[0072] Numerous rubber curing agents (also called vulcanizing agents), including sulfur or peroxide-based curing systems, may be used. Curing agents are described in Kirk-Othmer, Encyclopedia of Chemical Technology, Vol. 20, pp. 365-468, (3rd Ed. 1982), particularly 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. Vulcanizing agents can be used alone or in combination.

[0073] Other components typically used in rubber compounding may also be added to the rubber composition. These include accelerators, activators, oils, plasticizers, waxes, anticorrosion agents, processing aids, zinc oxide, tackifying resins, reinforcing resins, fatty acids, such as stearic acid, anti-corrosion agents, such as antioxidants and anti-ozone agents. In certain embodiments, oils used may include those conventionally used as spreadable oils, as described above.

[0074] All components of a rubber composition can be mixed using standard mixing equipment, such as a Banbury or Bravender mixer, extruder, kneader, and two-roll mill. In one or more embodiments, the components are mixed in two or more stages. In the first stage (often also called the masterbatch mixing stage), a so-called masterbatch (typically containing rubber components and fillers) is prepared. To prevent premature vulcanization (also known as scorching), the vulcanizing agent may be removed from the masterbatch. The masterbatch may be mixed at a starting temperature of about 25°C to about 125°C, with an extrusion temperature of about 135°C to about 180°C. Once the masterbatch is prepared, in the final mixing stage, the vulcanizing agent may be introduced into the masterbatch and mixed. This final mixing stage is typically carried out at a relatively low temperature to reduce the possibility of premature vulcanization. Optionally, an additional mixing stage, often called a re-mill, can be used between the masterbatch mixing stage and the final mixing stage. If silica is included as a filler in the rubber composition, one or more re-mill stages are often used. Various components, including the polymer of the present invention, can be added during these milling processes.

[0075] Mixing procedures and conditions particularly applicable to silica-filled tire formulations are described in U.S. Patents No. 5,227,425, 5,719,207, and 5,717,022, and European Patent No. 890,606, all of which are incorporated herein by reference. In one embodiment, the preparation of the initial masterbatch is carried out by incorporating the polymer and silica substantially in the absence of coupling agents and shielding agents.

[0076] Rubber compositions prepared from the polymers of the present invention are particularly useful in forming tire components, such as treads, sub-treads, sidewalls, body ply skims, bead fillers, and the like. In one or more embodiments, these tread or sidewall formulations may contain about 10% to about 100% by weight of the polymers of the present invention, about 35% to about 90% by weight in other embodiments, and about 50% to about 80% by weight in other embodiments (based on the total weight of rubber in the formulation).

[0077] When rubber compositions are used in the manufacture of tires, these compositions can be processed into tire components using conventional tire manufacturing techniques, such as standard rubber molding techniques, molding techniques, and curing techniques. Typically, vulcanization is carried out by heating the vulcanizable composition in a mold. For example, it may be heated to about 140 to about 180°C. The cured or crosslinked rubber composition may be called a vulcanized product, which generally contains a thermosetting three-dimensional polymer network structure. Other components (e.g., fillers and processing aids) may be uniformly dispersed throughout the crosslinked network structure. Pneumatic tires can be manufactured as discussed in U.S. Patents 5,866,171, 5,876,527, 5,931,211, and 5,971,046, which are incorporated herein by reference.

[0078] To demonstrate the implementation of the present invention, the following embodiments were prepared and tested. However, these embodiments should not be considered to limit the scope of the invention. The claims shall define the present invention. [Examples]

[0079] Several polymer samples were prepared in a 378.5 L reactor equipped with a heating / cooling jacket and stirrer blades. Random polymerization of butadiene and styrene with hexane was anionically initiated using butyllithium in a polymerization mixture containing approximately 18 wt% monomer. The target base molecular weight was 215 kg / mol (polystyrene standard), which was achieved based on the addition of butyllithium. By adjusting the ratio of styrene to butadiene, polymers with 10 wt% styrene and the remainder being butadiene were obtained. The vinyl content was targeted at 41.5 wt% of the butadiene meron units, which was obtained by using 2,2-di(tetrahydrofuryl)propane as a vinyl modifier. For example, in one or more samples, 35.397 kg of hexane, 7.579 kg of styrene at 33.0 wt% in hexane, and 135.669 kg of butadiene at 21.2 wt% in hexane were initially added to the reactor, followed by the addition of 0.511 kg of 3 wt% butyllithium, and then 0.012 kg of 2,2-di(tetrahydrofuryl)propane. This is merely an example, and it should be understood that various components in the samples (e.g., butyllithium) were manipulated to achieve the properties listed in Table I.

[0080] The monomer and solvent were placed in the reactor at room temperature, stirred, and heated to a stabilization temperature of 33°C. External heating was then discontinued, and a butyllithium initiator was added to form a polymerization mixture. The polymerization mixture generally produced an exothermic peak approximately 23 minutes after the addition of butyllithium, and the polymerization mixture was then subjected to constant temperature treatment at approximately 85°C using a cooling jacket.

[0081] Within approximately 5 minutes of reaching the peak polymerization temperature, the amount of 3-(1,3-dimethylbutylidene)aminopropyltriethoxysilane (DMAPT) provided in Table I was added to the reactor. The polymerization mixture was continuously stirred for approximately 30 minutes, after which a blend of ethylhexanoic acid (EHA) and octyltriethoxysilane (OTES) was added to the reactor in the amount shown in Table I. Then, 0.252 kg of butylated hydroxytoluene (BHT) was added. At this point in the process, the peak molecular weight was analyzed by GPC using polystyrene standards and the polystyrene Mark-Fwink constant (this analysis was also used to determine the coupling rate %), as well as the Mooney viscosity (ML at 100°C). 1+4 Samples were extracted to analyze the polymers at this point in the process. The polymers analyzed at this stage of the process may also be referred to as the “blending tank” (e.g., blending tank Mooney). For the purposes of this specification and the invention, the blending tank Mooney and the Mooney at desolvation are considered equivalent.

[0082] Next, the polymerization mixture was transferred to an aqueous desolvation process. Specifically, a tank containing water was heated to a temperature of approximately 82°C. The polymerization mixture was slowly added to this tank, allowing the hexane to volatilize, and the volatiles were collected in a condenser. The polymer solidified in the presence of water to form a solidified polymer dispersion. The polymer was then dehydrated by passing the polymer-water mixture through a grinder (i.e., a single-screw extruder with a perforating die). The dehydrated polymer was then dried in an oven at 71°C for 1 hour, and then heated in an oven at 60°C until dry (e.g., water content less than approximately 0.5% by weight). After drying, the polymer was baled and its Mooney viscosity (ML at 100°C) was measured. 1+4 The Mooney viscosity (ML at 100°C) of the bale samples was measured to obtain raw Mooney. The bale samples were aged by placing them in an oven at 100°C for 48 hours. The Mooney viscosity (ML at 100°C) of these aged samples was then measured. 1+4 ) was measured. [Table 1-1] [Table 1-2]

[0083] The data in Table I was analyzed using linear least squares regression analysis with Minitab™. This analysis provided the above formula for predicting blend tank and post-aging Mooney with a 95% confidence interval.

[0084] 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. This disclosure includes the following embodiments. <1> A process for preparing a stabilized diene copolymer having terminal modification, (i) Forming a polymerization mixture by combining an organolithium compound, a butadiene monomer, and a styrene monomer in a solvent, optionally together with a vinyl modifier, (ii) Polymerizing the monomer to form a living polymer, (iii) After the step of polymerizing the monomer, an imine-containing hydrocarbyloxysilane compound is introduced into the polymerization mixture, wherein the imine-containing hydrocarbyloxysilane is added in an amount of about 0.2 to 0.8 moles per mole of the organolithium compound, thereby forming a polymerization mixture containing a modified polymer. (iv) After the step of introducing the imine-containing hydrocarbyloxysilane, the hydrocarbylhydrocarbyloxysilane is introduced into the polymerization mixture containing the modified polymer, thereby forming a stabilized polymerization mixture, wherein the hydrocarbylhydrocarbyloxysilane is added in an amount of about 1 to about 12 moles per mole of organolithium compound to form a stabilized polymerization mixture. (v) To desolvate the polymer mixture to provide a stabilized diene copolymer having the terminal modification, A process that includes this. <2> The solvent removal step includes providing a wet polymer mass containing the modified polymer by vapor or water coagulation of the stabilized polymerization mixture, and drying the wet polymer mass to provide a dried modified polymer. <1> The process described above. <3> The step of polymerizing the monomer achieves the peak polymerization temperature, and the step of introducing an amine-containing hydrocarbyloxysilane compound into the polymerization mixture is performed after the peak polymerization temperature. <1> or <2> The process described above. <4> The step of combining an organolithium compound, a butadiene monomer, and a styrene monomer includes using about 0.05 to about 50 millimoles of butyllithium per 100 grams of total monomers. <1> ~ <3> The process described in any of the following. <5> The living polymer is characterized in that the base Mp, determined by GPC using polystyrene standards and polystyrene Mark-Fwink constants, is about 160 to about 280 kg per mole. <1> ~ <4> The process described in any of the following. <6> The living polymer is characterized by comprising approximately 5 to approximately 45% by weight of styrenemer units and approximately 10 to approximately 80% vinyl content. <1> ~ <5> The process described in any of the following. <7> The polymerization mixture containing the modified polymer contains about 10 to about 80 mol% of the modified polymer. <1> ~ <6> The process described in any of the following. <8> The amine-containing hydrocarbyloxysilane is selected from the group consisting of 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, or N-(4-N,N-dimethylaminobenzylidene)-3-(triethoxysilyl)-1-propanamine. <1> ~ <7> The process described in any of the above. In a particular embodiment, the imine-containing hydrocarbyloxysilane is N-(1-methylpropyridene)-3-(triethoxysilyl)-1-propanamine and N-(1,3-dimethylbutylidene)-3-(triethoxysilyl)-1-propanamine. <9> The step of introducing the amine-containing hydrocarbyloxysilane includes adding the amine-containing hydrocarbyloxysilane to the polymerization mixture in an amount of about 0.3 to about 0.7 moles per mole of organolithium compound. <1> ~ <8> The process described in any of the following. <10> The hydrocarbylhydrocarbyloxysilane is selected from the group consisting of trihydrocarbylhydrocarbyloxysilane, dihydrocarbyldihydrocarbyloxysilane, hydrocarbyltrihydrocarbyloxysilane, and tetrahydrocarbyloxysilane. <1> ~ <9> The process described in any of the following. <11> The step of introducing hydrocarbylhydrocarbyloxysilane includes introducing about 3 to about 10 moles per mole of organolithium compound, <1> ~ <10> The process described in any of the following. <12> The process further includes introducing a condensation accelerator into the polymerization mixture or the stabilized polymerization mixture containing a modified polymer, <1> ~ <11> The process described in any of the following. <13> The amount of condensation accelerator introduced is approximately 1.0 to 4.0 moles of condensation accelerator per mole of lithium, as described above. <12> The process described above. <14> The modified polymer in the stabilized polymerization mixture has a Mooney viscosity greater than 50 (ML at 100°C). 1+4 ) having the above <1> ~ <13> The process described in any of the following. <15> The following is an operation to provide a modified polymer in the stabilized polymerization mixture that satisfies the following formula, <1> ~ <14> The process described in any of the following: Mooney viscosity after solvent removal = 44.7 + [0.5218 base Mp] - [5.1 equivalent of functionalizing agent] - [4.765 equivalent of stabilizer] + [8.86 equivalent of condensation accelerator] (In the formula, the Mooney viscosity during solvent removal is 50 or higher, Mp is approximately 160 to 280 kg / mol, the functionalizing agent equivalent is approximately 0.2 to 0.8 moles per mole of organolithium compound, the stabilizer equivalent is approximately 1 to 12 moles per mole of organolithium compound, and the condensation accelerator equivalent is approximately 1 to 4 moles per mole of organolithium compound.) <16> The stabilized diene copolymer, after heating and aging at 100°C for 48 hours, has a Mooney viscosity of less than 120 (ML at 100°C). 1+4 The process is characterized in that the process is carried out such that it satisfies the following equation. <1> ~ <15> The process described in any of the following: Mooney viscosity after aging = -34.2 + [Mooney viscosity of 0.828 bales] + [0.348 base Mp] - [0.425% coupling %] + [98.9 equivalent of functionalizer] - [6.16 equivalent of stabilizer] (In the formula, the Mooney viscosity after aging is 120 or less, the Mooney viscosity of the bale is approximately 35 to 120, Mp is approximately 160 to 280 kg / mol, the coupling % is approximately 20 to 80%, the functionalizing agent equivalent is approximately 0.2 to 0.8 moles per mole of organolithium compound, and the stabilizer equivalent is approximately 1 to 12 moles per mole of lithium.)

Claims

1. A process for preparing a stabilized diene copolymer having terminal modification, (i) Forming a polymerization mixture by combining an organolithium compound, a butadiene monomer, and a styrene monomer in a solvent, optionally together with a vinyl modifier, (ii) Polymerizing the monomers to form a living polymer, (iii) After the step of polymerizing the monomer, an imine-containing hydrocarbyloxysilane compound is introduced into the polymerization mixture as a modifier, wherein the imine-containing hydrocarbyloxysilane compound is added in an amount of 0.2 to 0.8 moles per mole of organolithium compound, thereby forming a polymerization mixture containing a modified polymer, (iv) After the step of introducing an imine-containing hydrocarbyloxysilane compound, a compound defined by the following formula I is introduced as a stabilizer into the polymerization mixture containing the modified polymer, thereby forming a stabilized polymerization mixture, wherein the compound defined by the following formula I is added in an amount of 1 to 12 moles per mole of organolithium compound to form a stabilized polymerization mixture, 【Chemistry 1】 (In the formula, R ２ is a hydrocarbyl group, R ３ , R ４ , and R ５ These are, independently, a hydrocarbyl group or a hydrocarbyloxy group. (v) Introducing a condensation accelerator in an amount of 1.0 to 4.0 moles per mole of lithium into the polymerization mixture or the stabilized polymerization mixture containing the modified polymer, (vi) To desolvent the polymer mixture to provide a stabilized diene copolymer having the terminal modification, A process that includes, In order to achieve the target Mooney viscosity during desolvation and the target Mooney viscosity after aging, the peak molecular weight of the base polymer of the stabilized polymerization mixture, the amount of the modifier, the amount of the stabilizer, the coupling efficiency measured by the coupling percentage of the base polymer of the stabilized polymerization mixture, and the amount of the condensation accelerator are all taken into consideration and adjusted. The aforementioned post-aging Mooney is 120 or less, where post-aging Mooney refers to the ML at 100°C after heating and aging at 100°C for 48 hours. １＋４ And, A process operated to provide a modified polymer in the stabilized polymerization mixture that satisfies the following formula: Mooney viscosity after solvent removal = 44.7 + [0.5218 base Mp] (unit of base Mp: kg per mole) - [5.1 equivalent of modifier] - [4.765 equivalent of stabilizer] + [8.86 equivalent of condensation accelerator] (In the formula, the Mooney viscosity during desolvation is 50 to 105, where Mooney viscosity during desolvation is defined as the viscosity at 100°C during the desolvation process.) １＋４ The base Mp is 160 to 280 kg per mole, the modifier equivalent is 0.2 to 0.8 moles per mole of organolithium compound, the stabilizer equivalent is 1 to 12 moles per mole of organolithium compound, and the condensation accelerator equivalent is 1 to 4 moles per mole of organolithium compound.

2. The process according to claim 1, wherein the solvent removal step comprises providing a wet polymer mass containing the modified polymer by vapor or water coagulation of the stabilized polymerization mixture, and drying the wet polymer mass to provide a dry modified polymer.

3. The process according to claim 1, wherein the step of polymerizing a monomer is performed to achieve a peak polymerization temperature, and the step of introducing an imine-containing hydrocarbyloxysilane compound into the polymerization mixture is performed after the peak polymerization temperature.

4. The process according to claim 1, carried out such that the following equation is satisfied: Mooney viscosity after aging = -34.2 + [Mooney viscosity of 0.828 bales] + [0.348 base Mp] (unit of base Mp: kg per mole) - [0.425 coupling %] + [98.9 modifier equivalent] - [6.16 stabilizer equivalent] (In the formula, the Mooney viscosity after aging is 70 to 120, the Mooney viscosity of the bale is 35 to 120, the base Mp is 160 to 280 kg per mole, the coupling % is 20 to 80%, the modifier equivalent is 0.2 to 0.8 moles per mole of organolithium compound, and the stabilizer equivalent is 1 to 12 moles per mole of lithium.)

Images