Linear telechelic diene copolymers and their use in tire components

Abstract

A method for preparing a linear telechelic diene copolymer, the method comprising (i) preparing a dilithium initiator by reacting dialkenyl compound with an alkyl lithium compound; (ii) introducing the dilithium initiator, diene monomer, vinyl aromatic monomer, and a randomizer to form a polymerization mixture; (iii) allowing the diene monomer and vinyl aromatic monomer to polymerize and form a polymer having first and second reactive ends; and (iv) functionalizing both the first and second reactive ends of the polymer by reacting the first and second reactive ends with first and second functionalizing agents to thereby form a linear telechelic diene copolymer.

Description

LINEAR TELECHELIC DIENE COPOLYMERS AND THEIR USE IN TIRE COMPONENTSFIELD OF THE INVENTION

[0001] Embodiments of the present invention provide linear telechelic diene copolymers,as well as their use of the branched polymers in the preparation of tire components.BACKGROUND OF THE INVENTION

[0002] Polydienes, such as poly(butadiene) and diene copolymers, such as poly(styrene-co-butadiene) are often made by employing anionic polymerization techniques wherebydiene monomer, optionally together with copolymerizable monomer such as vinylaromatics, are polymerized using an anionic initiator. The use of anionic polymerizationtechniques leads to several advantages including the ability to control molecular weight,prepare relatively linear polymer chains, and functionalize the polymer chain through achain termination reaction. Useful anionic initiators may include, for example, alkyl lithiumcompounds such as n-butyl lithium. Multi-functional initiators can be formed by reacting,for example, an alkyl lithium compound with a dialkenyl compound such asdiisopropenylbenzene. Polymers prepared by using multi-functional initiators havemultiple reactive chain ends, which provides the ability to functionalize both ends of apolymer chain to form a telechelic polymer.SUMMARY OF THE INVENTION

[0003] One or more embodiments of the present invention provide a method forpreparing a linear telechelic diene copolymer, the method comprising (i) preparing adilithium initiator by reacting dialkenyl compound with an alkyl lithium compound; (ii)introducing the dilithium initiator, diene monomer, vinyl aromatic monomer, and arandomizer to form a polymerization mixture; (iii) allowing the diene monomer and vinylaromatic monomer to polymerize and form a polymer having first and second reactive ends;and (iv) functionalizing both the first and second reactive ends of the polymer by reactingthe first and second reactive ends with first and second functionalizing agents to therebyform a linear telechelic diene copolymer.

[0004] Other embodiments of the present invention provide a vulcanizable compositionof matter including a linear telechelic polymer.

[0005] Still other embodiments of the present invention provide a vulcanizate preparedby vulcanizing a vulcanizable composition of matter including a linear telechelic polymer .

[0006] Yet other embodiments of the present invention provide a tire componentprepared from a vulcanizable composition including a linear telechelic polymer.

[0007] Still yet other embodiments of the present invention provide a tire tread preparedfrom a vulcanizable composition including a linear telechelic polymer.

[0008] Other embodiments of the present invention provide a vulcanizable compositioncomprising (i) a linear telechelic diene copolymer prepared by preparing a dilithium initiatorby reacting dialkenyl compound with an alkyl lithium compound; introducing the dilithiuminitiator, diene monomer, vinyl aromatic monomer, and a randomizer to form apolymerization mixture; allowing the diene monomer and vinyl aromatic monomer topolymerize and form a polymer having first and second reactive ends; and functionalizingboth the first and second reactive ends of the polymer by reacting the first and secondreactive ends with first and second functionalizing agents to thereby form a linear telechelicdiene copolymer; (ii) silica; and (iii) a curative.

[0009] Still other embodiments of the present invention provide a method for forming avulcanizable composition, the method comprising (i) providing a linear telechelic dienecopolymer prepared by preparing a dilithium initiator by reacting dialkenyl compound withan alkyl lithium compound; introducing the dilithium initiator, diene monomer, vinylaromatic monomer, and a randomizer to form a polymerization mixture; allowing the dienemonomer and vinyl aromatic monomer to polymerize and form a polymer having first andsecond reactive ends; and functionalizing both the first and second reactive ends of thepolymer by reacting the first and second reactive ends with first and second functionalizingagents to thereby form a linear telechelic diene copolymer; (ii) providing silica; (iii)providing a curative; and mixing the linear telechelic diene copolymer, silica, and curative toform the vulcanizable composition.DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

[0010] Embodiments of the invention are based, at least in part, on the discovery of lineartelechelic diene copolymers prepared by polymerizing monomer with a dilithium initiator.According to embodiments of the invention, the dilithium initiator is prepared by reactingan alkyl lithium compound with a dialkenyl compound and allowing the initiator to age.Initiator aging in the presence of a Lewis base has also been found to contribute to improvedpolymer properties. Inasmuch as the polymers are prepared by anionic polymerizationtechniques, the use of a dilithium initiator advantageously leads to multiple polymer liveends (i.e. reactive ends), which allows for preparing telechelic diene copolymers.PREPARATION OF LINEAR TELECHELIC COPOLYMERS

[0011] In one or more embodiments, the linear telechelic diene copolymers, which maybe referred to as difunctional copolymers or difunctionalized polymers or simplyfunctionalized polymers, are prepared by polymerizing diene monomer together with vinylaromatic monomer, with a dilithium initiator. The dilithium initiator is prepared by reactingan alkyl lithium compound with a dialkenyl compound. In one or more embodiments, thedilithium initiator is aged in an appropriate solvent in the presence of a Lewis base prior toits use in polymerization.INITIATOR PREPARATION AND AGING

[0012] As indicated above, the dilithium initiator is prepared by combining a dialkenylcompound with an alkyl lithium compound within a solvent that forms a reaction mixture inwhich the reactants and product are at least partially soluble. The initiator is then aged inan appropriate solvent in the presence of a Lewis base.

[0013] In one or more embodiments, the dialkenyl compound is a 1,3-dialkenylbenzenecompound such as 1,3-diisopropenylbenzene. In one or more embodiments, the alkyllithium compound is a butyl lithium compound such as n-butyl lithium, t-butyl lithium,and / or sec-butyl lithium. In particular embodiments, sec-butyl lithium is employed.

[0014] The Lewis base may include any Lewis base that does not include an activehydrogen atom, where the presence of an active hydrogen atom is determined by theZerewitinoff test. Exemplary Lewis bases include oxolanyl propanes such as 2,2-bis(2-oxolanyl)propane (also known as 2,2-ditetrahydrofurylpropane), meso-2,2-diterahydrofurylpropane, DL-2,2,-ditetrahdydrofurlypropane,tetramethylethylenediamine, and mixtures thereof, as well as trialkyl amines such as triethylamine. In particular embodiments, triethyl amine is employed.

[0015] The amount of alkyl lithium compound reacted with the dialkenyl compound maybe quantified based upon the molar ratio of lithium to alkenyl groups; that is, equivalents oflithium associated with the alkyl lithium compound (i.e. mole of Li) relative to theequivalents of alkenyl groups within the dialkenyl compound (e.g. equivalents of isopropenylgroups within 1,3-diisopropenylbenzene. In one or more embodiments, the molar ratio ofmoles of Li associated with the alkyl lithium to equivalents of alkenyl groups associated withthe dialkenyl compound may be from about 1.95:1 to about 2.05:1, in other embodimentsfrom about 1.97:1 to about 2.03:1, and in other embodiments from about 1.99:1 to about2.01:1. Where sec-butyl lithium is reacted with 1,3-diisopropenylbenzene, 2.00 moles of sec-butyl lithium may be reacted with each mole of 1,3-diisopropenylbenzene.

[0016] The synthesis of the initiator takes place within a solvent in which the reactantsand the product is at least partially soluble. Useful solvents include, but are not limited to,hydrocarbons with a low or relatively low boiling point such as aromatic hydrocarbons,aliphatic hydrocarbons, and cycloaliphatic hydrocarbons. Non-limiting examples ofaromatic hydrocarbons include benzene, toluene, xylenes, ethylbenzene, diethylbenzene,and mesitylene. Non-limiting examples of aliphatic hydrocarbons include n-pentane, n-hexane, n-heptane, n-octane, n-nonane, n-decane, isopentane, isohexanes, isopentanes,isooctanes, 2,2-dimethylbutane, petroleum ether, kerosene, and petroleum spirits. And,non-limiting examples of cycloaliphatic hydrocarbons include cyclopentane, cyclohexane,methylcyclopentane, and methylcyclohexane. Mixtures of the above hydrocarbons may alsobe used.

[0017] As indicated above, the dilithium initiator formed by the foregoing reaction isaged within an appropriate solvent (e.g. within the reaction medium) in the presence of aLewis base. In one or more embodiments, the Lewis base is present at the introduction ofthe reactants to the reaction mixture. In other embodiments, the Lewis base is introducedafter synthesis of the dilithium initiator, and aging takes place after introduction of the Lewisbase.

[0018] The amount of Lewis base introduced to the reaction mixture may be quantifiedbased upon the moles of Lewis base (e.g.2,2-ditetrahydrofurylpropane) relative to the molesof lithium associated with the alkyl lithium compound (i.e. molar ratio of moles Lewis baseto moles of lithium). In one or more embodiments, the molar ratio of moles of Lewis baseintroduced to the reaction medium to moles of lithium introduced with the alkyl lithiumcompound is from about 0.05:1 to about 1:1, in other embodiments from about 0.1:1 to about0.6:1, and in other embodiments from about 0.2:1 to about 0.45:1.

[0019] In one or more embodiments, aging of the initiator takes place under an inertatmosphere at atmospheric conditions at a temperature of from about 0 to about 150 ℃, inother embodiments from about 25 to about 100 ℃, and in other embodiments from about35 to about 60 ℃. In one or more embodiments, the initiator is aged for greater than 15minutes, in other embodiments greater than 20 minutes, in other embodiments greater than25 minutes, and in other embodiments greater than 30 minutes before introducing theinitiator to the monomer to be polymerized. In one or more embodiments, the initiator isaged for from about 15 minutes to about 4 hours, in other embodiments from about 20minutes to about 3 hours, and in other embodiments from about 30 minutes to about 2 hoursbefore introducing the initiator to the monomer to be polymerized. The appropriate agingtime is temperature dependent; that is, the time necessary to age the initiator decreases withincreased temperature. Likewise, the maximum amount of aging decreases withtemperature. It should also be appreciated that the temperature dependence of the agingprocess may allow for longer storage times at cold temperatures. For example, it is believedthat the initiator (i.e. the combination of the dialkenyl compound and the alkyl lithium) canbe stored for periods of, for example, 24 hours at temperatures below 0 ℃.POLYMERIZATION REACTION

[0020] The dilithium initiator as prepared above, and optionally aged, is combined withmonomer to be polymerized, within an appropriate a solvent to form a polymerizationmixture in which the monomer and resulting polymer are at least partially soluble. In oneor more embodiments, the initiator is also at least partially soluble within the polymerizationmixture.

[0021] Generally speaking, the polymerization of monomer by the initiator proceeds byanionic polymerization techniques. The preparation of polymer by employing anionicpolymerization techniques is generally known. The key mechanistic features of anionicpolymerization have been described in books (e.g., Hsieh, H. L.; Quirk, R. P. AnionicPolymerization: Principles and Practical Applications; Marcel Dekker: New York, 1996) andreview articles (e.g., Hadjichristidis, N.; Pitsikalis, M.; Pispas, S.; Iatrou, H.; Chem. Rev. 2001,101(12), 3747-3792). Anionic initiators may advantageously produce polymer havingreactive chain ends (e.g., living polymers) that, prior to quenching, are capable of reactingwith additional monomers for further chain growth or reacting with certain functionalizingagents to give functionalized polymers. The polymers having reactive polymer chain endsmay simply be referred to as reactive polymers. As those skilled in the art appreciate, thesereactive polymers include a reactive chain end, which is believed to be ionic, at which areaction between a functionalizing agent and the reactive chain end of the polymer can takeplace, which thereby imparts a functionality or functional group to the polymer chain end,or which may couple multiple polymers together.

[0022] The polymerization mixture can be formed by introducing the variousconstituents in any order. For example, in one or more embodiments, the monomer, andsolvent can first be combined, and then the aged initiator can be introduced to the mixture.MONOMER TO BE POLYMERIZED

[0023] As indicated above, the monomer to be polymerized includes conjugated dienemonomer and vinyl-substituted aromatic monomer, which may also be referred to as vinylaromatic monomer or comonomer. Examples of conjugated diene monomer include1,3-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. Mixtures of two or more conjugated dienes may also beutilized in copolymerization. Examples of vinyl-substituted aromatic monomer includestyrene, p-methylstyrene, α-methylstyrene, and vinylnaphthalene.

[0024] The amount of the initiator to be employed may depend on the interplay ofvarious factors such as the type of initiator employed, the purity of the ingredients, thepolymerization temperature, the polymerization rate and conversion desired, the molecularweight desired, and many other factors. In one or more embodiments, the amount ofinitiator employed may be expressed as the mmols of initiator per weight of monomer. Inone or more embodiments, the amount of initiator introduced to the polymerization mixtureis from about 0.1 to about 100 mmol, or in other embodiments from about 0.2 to about 50mmol, or in other embodiments from about 0.3 to about 15 mmol of the initiator per 100gram of monomer within the polymerization mixture (i.e. monomer to be polymerized).SOLVENT FOR POLYMERIZATION MIXTURE

[0025] In one or more embodiments, suitable solvents include those organic compoundsthat will not undergo polymerization or incorporation into propagating polymer chainsduring the polymerization of monomer in the presence of catalyst. In one or moreembodiments, these organic species are liquid at ambient temperature and pressure. In oneor more embodiments, these organic solvents are inert to the catalyst. Exemplary organicsolvents include hydrocarbons with a low or relatively low boiling point such as aromatichydrocarbons, aliphatic hydrocarbons, and cycloaliphatic hydrocarbons. Non-limitingexamples of aromatic hydrocarbons include benzene, toluene, xylenes, ethylbenzene,diethylbenzene, and mesitylene. Non-limiting examples of aliphatic hydrocarbons includen-pentane, n-hexane, n-heptane, n-octane, n-nonane, n-decane, isopentane, isohexanes,isopentanes, isooctanes, 2,2-dimethylbutane, petroleum ether, kerosene, and petroleumspirits. And, non-limiting examples of cycloaliphatic hydrocarbons include cyclopentane,cyclohexane, methylcyclopentane, and methylcyclohexane. Mixtures of the abovehydrocarbons may also be used. The low-boiling hydrocarbon solvents are typicallyseparated from the polymer upon completion of the polymerization. Other examples oforganic solvents include high-boiling hydrocarbons of high molecular weights, such asparaffinic oil, aromatic oil, or other hydrocarbon oils that are commonly used to oil-extendpolymers. Since these hydrocarbons are non-volatile, they typically do not requireseparation and remain incorporated in the polymer.MODIFIER

[0026] The polymerization reaction may be conducted in the presence of a modifier,which may also be referred to as a polar coordinator or a vinyl modifier. As those skilled inthe art appreciate, these compounds may serve multiple roles in the polymerization. Forexample, they can assist in randomizing comonomer throughout the polymer chain; theymay also modify the vinyl content of the mer units deriving from dienes. Compounds usefulas modifiers include those having an oxygen or nitrogen heteroatom and a non-bonded pairof electrons. Examples include linear and cyclic oligomeric oxolanyl alkanes; dialkyl ethersof mono and oligo alkylene glycols (also known as glyme ethers); “crown” ethers; tertiaryamines; linear THF oligomers; and the like. Linear and cyclic oligomeric oxolanyl alkanesare described in U.S. Patent Nos. 4,429,091 and 9,868,795, which are incorporated herein byreference. Specific examples of compounds useful as randomizers include 2,2-bis(2-oxolanyl)propane (also known as 2,2-ditetrahydrofurylpropane), meso-2,2-diterahydrofurylpropane, DL-2,2,-ditetrahdydrofurlypropane, 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 , andmixtures thereof. In other embodiments, potassium alkoxides can be used to randomize thestyrene distribution. In one or more embodiments, a randomizer other than a potassiumalkoxide is employed. In other embodiments, potassium alkoxide is the only randomizerpresent within the polymerization mixture.

[0027] The amount of randomizer to be employed may depend on various factors suchas the desired microstructure of the polymer, the ratio of monomer to comonomer, thepolymerization temperature, as well as the nature of the specific randomizer employed.POLYMERIZATION CONDITIONS AND TECHNIQUES

[0028] The anionic initiator and the randomizer can be introduced to the polymerizationsystem by various methods. In one or more embodiments, the anionic initiator and therandomizer may be added separately to the monomer to be polymerized in either a stepwiseor simultaneous manner.

[0029] As indicated above, polymerization of conjugated diene monomer and vinylaromatic monomer, in the presence of an effective amount of initiator, produces a reactivepolymer. The introduction of the initiator, the conjugated diene monomer, the comonomer,and the solvent forms a polymerization mixture in which the reactive polymer is formed.Polymerization within a solvent produces a polymerization mixture in which the polymerproduct is dissolved or suspended in the solvent. This polymerization mixture may bereferred to as a polymer cement.

[0030] In one or more embodiments, the polymerization may be conducted in anyconventional polymerization vessel known in the art. For example, the polymerization canbe conducted in a conventional stirred-tank reactor. In one or more embodiments, all of theingredients used for the polymerization can be combined within a single vessel (e.g., aconventional stirred-tank reactor), and all steps of the polymerization process can beconducted within this vessel. In other embodiments, two or more of the ingredients can bepre-combined in one vessel and then transferred to another vessel where the polymerizationof monomer (or at least a major portion thereof) may be conducted. Because variousembodiments of the present invention include the use of multiple reactors or reaction zones,the vessel (e.g., tank reactor) in which the polymerization is conducted may be referred to asa first vessel or first reaction zone.

[0031] The polymerization can be carried out as a batch process, a continuous process,or a semi-continuous process. In the semi-continuous process, the monomer isintermittently charged as needed to replace that monomer already polymerized. In one ormore embodiments, the heat of polymerization may be removed by external cooling by athermally controlled reactor jacket, internal cooling by evaporation and condensation of themonomer through the use of a reflux condenser connected to the reactor, or a combinationof the two methods. Also, conditions may be controlled to conduct the polymerization undera pressure of from about 0.1 atmospheres to 50 atmospheres, in other embodiments fromabout 0.5 atmosphere to about 20 atmospheres, and in other embodiments from about 1atmosphere to about 10 atmospheres. In one or more embodiments, the pressures at whichthe polymerization may be carried out include those that ensure that the majority of themonomer is in the liquid phase. In these or other embodiments, the polymerization mixturemay be maintained under anaerobic conditions.

[0032] In one or more embodiments, the conditions under which the polymerizationproceeds may be controlled to maintain the peak polymerization temperature of thepolymerization mixture at greater than 30 °C, in other embodiments greater than 50 °C, andin other embodiments greater than 70 °C. In these or other embodiments, the conditionsunder which the polymerization proceeds may be controlled to maintain the peakpolymerization temperature of the polymerization mixture at less than 120 °C, in otherembodiments less than 110 °C, and in other embodiments less than 100 °C. In one or moreembodiments, the conditions under which the polymerization proceeds may be controlledto maintain the temperature of the polymerization mixture within a range from about -10 °Cto about 200 °C, in other embodiments from about 0 °C to about 150 °C, and in otherembodiments from about 20 °C to about 110 °C.PRE-FUNCTIONALIZATION POLYMER CHARACTERISTICS

[0033] Prior to functionalization, which is further described below, the linear, reactivepolymers may be characterized by their molecular weight, which may include numberaverage molecular weight (Mn), weight average molecular weight (Mw), and peak molecularweight (Mp). As those skilled in the art will appreciate, molecular weight can be determined,for example, by using gel permeation chromatography (GPC) together with an UVabsorption, differential refractometer (DRI), refractive index (RI), infrared (IR) absorptiondetector and by employing appropriate calibration standards and THF as a solvent. Forpurposes of this specification, GPC measurements employ polystyrene standards andpolystyrene Mark Houwink constants unless otherwise specified. For purposes of thisspecification, prior to functionalization, the polymer may be referred to as the base polymer,and the pre-functionalized characteristics of the polymer may be referred to as thecharacteristics of the base polymer.

[0034] In one or more embodiments, the pre-functionalized polymers have an Mp, whichmay also be referred to as the base Mp, of greater than 160 kg / mol, in other embodimentsgreater than 170 kg / mol, and in other embodiments greater than 180 kg / mol. In these orother embodiments, the pre-functionalized polymers have a base Mp of less 280 kg / mol, inother embodiments less than 260 kg / mol, and in other embodiments less than 250 kg / mol.In one or more embodiments, the pre-functionalized polymers have a base Mp of from about160 to about 280 kg / mol, in other embodiments from about 170 to about 260 kg / mol, andin other embodiments from about 180 to about 250 kg / mol.

[0035] In one or more embodiments, the pre-functionalized polymers have an Mn, whichmay also be referred to as the base Mn, of greater than 130 kg / mol, in other embodimentsgreater than 140 kg / mol, and in other embodiments greater than 150 kg / mol. In these orother embodiments, the pre-functionalized polymers have a base Mn of less 300 kg / mol, inother embodiments less than 280 kg / mol, and in other embodiments less than 260 kg / mol.In one or more embodiments, the pre-functionalized polymers have a base Mn of from about130 to about 300 kg / mol, in other embodiments from about 140 to about 280 kg / mol, andin other embodiments from about 150 to about 260 kg / mol.

[0036] In one or more embodiments, the pre-functionalized polymers have an Mw, whichmay also be referred to as the base Mw, of greater than 180 kg / mol, in other embodimentsgreater than 190 kg / mol, and in other embodiments greater than 200 kg / mol. In these orother embodiments, the pre-functionalized polymers have a base Mw of less 500 kg / mol, inother embodiments less than 450 kg / mol, and in other embodiments less than 400 kg / mol.In one or more embodiments, the pre-functionalized polymers have a base Mw of from about180 to about 500 kg / mol, in other embodiments from about 190 to about 450 kg / mol, andin other embodiments from about 200 to about 400 kg / mol.

[0037] In one or more embodiments, the base polymer is monomodal. In these or otherembodiments, the base polymer may be characterized by a polydispersity, which may alsobe referred to as a molecular weight distribution (Mw / Mn) of less than of less than 3, in otherembodiments less than 2.5, in other embodiments less than 2.0, and in other embodimentsless than 1.8.

[0038] The pre-functionalized polymers produced according to aspects of the presentinvention may be characterized by vinyl content, which may be described as the number ofunsaturations in the 1,2-microstructure relative to the total unsaturations within thepolymer chain. As the skilled person will appreciate, vinyl content can be determined byNMR analysis at 400 MHz using CDCl3 as a solvent. In one or more embodiments, the pre-functionalized polymers include greater than 5%, in other embodiments greater than 8%, inother embodiments greater than 10%, in other embodiments greater than 20%, and in otherembodiments greater than 35% vinyl. In these or other embodiments, the pre-functionalized polymers include less than 80%, in other embodiments less than 60%, and inother embodiments less than 46%. In one or more embodiments, the pre-functionalizedpolymers include from about 5% to about 80%, in other embodiments from about 8% toabout 60%, and in other embodiments from about 20% to about 46% vinyl.

[0039] The pre-functionalized polymers produced according to aspects of the presentinvention may be characterized by bound styrene content (i.e. the amount of styreneincorporated in the polymer chains), which refers to the weight percent vinyl aromaticmonomer incorporated into polydiene copolymers. As the skilled person appreciates, boundstyrene can be determined with reference to the relative weight of vinyl monomer includedinto the polymerization mixture relative to the diene monomer. Alternatively, bound styrenecan be determined by NMR analysis at 400 MHz using CDCl3 as a solvent. In one or moreembodiments, the pre-functionalized polymers include greater than 20 wt %, in otherembodiments greater than 25 wt %, and in other embodiments greater than 30 wt % boundstyrene. In these or other embodiments, the pre-functionalized polymers include less than60 wt %, in other embodiments less than 55 wt %, and in other embodiments less than 50wt % bound styrene. In one or more embodiments, the pre-functionalized polymers includefrom about 20 to about 60 wt %, in other embodiments from about 25 to about 55 wt %, andin other embodiments from about 30 to about 50 wt % bound styrene.

[0040] The pre-functionalized polymers produced according to aspects of the presentinvention may be characterized by T80, which is determined according to ASTM D 1646-19Aby using a Mooney viscometer (e.g. Agilent Technologies) with a large rotor at 100 °C with a4 minute run time after 1 minute of preheating (i.e. ML 1+4 @ 100 °C). In one or moreembodiments, the pre-functionalized polymers have a T80 of less than 2 seconds, in otherembodiments less than 1.8 seconds, in other embodiments less than 1.6 seconds, and in otherembodiments less than 1.4 seconds.POLYMER FUNCTIONALIZATION

[0041] The polymer produced by the polymerization of this invention (i.e. whichproceeds by anionic polymerization techniques) includes reactive ends (i.e. the growingends) that are capable of being modified, which may also be referred to as functionalized, toprovide functionalized polymers having a functional group at both ends of a linear polymer,which may be referred to as a telechelic polymer. That is, the reactive ends of the polymerare modified, which may also be referred to as functionalized, by introducing afunctionalizing agent to the polymerization mixture. It is believed that the polymer chainends react with the functionalizing agent (which may also be referred to as a modifyingagent) to provide a residue of the functionalizing agent at the end of the polymer chain.Accordingly, the reaction between the polymer and the functionalizing agents produces apolymer composition wherein both ends of a linear polymer include a terminal groupderiving from the functionalizing agent. It should be appreciated that the reaction betweenthe functionalizing agent and the reactive ends of the polymer can also result in polymercoupling of two or more polymer chains. In either event, the polymers bearing a chain-endfunctional group or polymers coupled with the residue of the functionalizing agent will bothbe referred to as modified or functionalized branched polymers unless otherwisedesignated. It should also be appreciated that the respective functionalizing agents thatreact with the respective reactive ends of the polymer may be of the same or different typeof functionalizing agent; i.e. the may be of the same or different chemical species. The skilledperson appreciates that two or more functionalizing agents of different chemical species maybe introduced to the reactive polymer and that different chemical species may react at eachof the respective ends of the polymer chain. Alternatively, the same chemical species mayreact at each end. The latter would be the result if one chemical specie of functionalizingagent is introduced to the reactive polymer.FUNCTIONALIZING AGENTS

[0042] Useful functionalizing agents include those functionalizing agents conventionallyemployed in the art. In one or more embodiments, the functionalizing agent imparts aterminal functionality that can be reactive or interactive with other polymer chains(propagating and / or non-propagating) or with other materials in a rubber compound suchas particulate reinforcing fillers (e.g. carbon black or silica). As described above, enhancedinteractivity between a polymer and particulate fillers in rubber compounds improves themechanical and dynamic properties of resulting vulcanizates. For example, certainfunctionalizing agents can impart a terminal functionality that includes one or moreheteroatoms. In one or more embodiments, the functionalizing agent may produce afunctionalized polymer that can be used in rubber compositions from which vulcanizates canbe provided, and these vulcanizates can possess high temperature (e.g., 50 °C) hysteresislosses that are less than those possessed by vulcanizates prepared from similar rubbercompounds that do not include the functionalized polymers. Reductions in high temperaturehysteresis loss can be at least 5%, sometimes at least 10%, and occasionally at least 15%.

[0043] Exemplary types of compounds that can be used to end-functionalize the reactivebranched polymers of this invention include imines, amines, hydrocarbyloxy silanes, amine-containing hydrocarbyloxy silanes, halogenated organics, trialkyl tin compounds, carbondioxide, benzophenones, benzaldehydes, imidazolidones, pyrrolidinones, carbodiimides,ureas, isocyanates, and Schiff bases. It should also be appreciated that two or more differentspecies of functionalizing agent can be employed in practicing the present invention.HYDROCARBYLOXY SILANE FUNCTIONALIZING AGENTS

[0044] In one or more embodiments, hydrocarbyloxy silane functionalizing agents maybe defined by the formula:(R1)4-z-ySi(R2) y (OR2)zwhere R1 is a halogen atom or a monovalent organic group, each R2 is a monovalent organicgroup, z is an integer from 1 to 4, and y is an integer from 0 to 2. In one embodiment, thehalogen atom is chlorine.

[0045] In one or more embodiments, the monovalent organic groups include hydrocarbylgroups such as, but not limited to, alkyl, cycloalkyl, alkenyl, cycloalkenyl, aryl, allyl, aralkyl,alkaryl, or alkynyl groups. Hydrocarbyl groups also include substituted hydrocarbyl groups,which refer to hydrocarbyl groups in which one or more hydrogen atoms have been replacedby a substituent such as a hydrocarbyl group. In one or more embodiments, these groupsmay include from one, or the appropriate minimum number of carbon atoms to form thegroup, to about 20 carbon atoms. These groups may or may not contain heteroatoms.Suitable heteroatoms include, but not limited to, nitrogen, boron, oxygen, silicon, sulfur, tin,and phosphorus atoms. In one or more embodiments, the cycloalkyl, cycloalkenyl, and arylgroups are non-heterocyclic groups. In these or other embodiments, the substituentsforming substituted hydrocarbyl groups are non-heterocyclic groups.

[0046] Suitable examples of siloxane terminating agents include tetraalkoxysilanes,alkylalkoxysilanes, arylalkoxysilanes, alkenylalkoxysilanes, and haloalkoxysilanes.

[0047] Examples of tetraalkoxysilane compounds include tetramethyl orthosilicate,tetraethyl orthosilicate, tetrapropyl orthosilicate, tetrabutyl orthosilicate, tetra(2-ethylhexyl) orthosilicate, tetraphenyl orthosilicate, and tetratoluyloxysilane.

[0048] Examples of alkylalkoxysilane compounds include methyltrimethoxysilane,methyltriethoxysilane, methyltri-n-propoxysilane, methyltri-n-butoxysilane,methyltriphenoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltri-n-propoxysilane, ethyltri-n-butoxysilane, ethyltriphenoxysilane, dimethyldimethoxysilane,dimethyldiethoxysilane, dimethyldi-n-propoxysilane, dimethyldi-n-butoxysilane,dimethyldiphenoxysilane, diethyldimethoxysilane, and diphenyldimethoxysilane.

[0049] Examples of arylalkoxysilane compounds include phenyltrimethoxysilane,phenyltriethoxysilane, phenyltri-n-propoxysilane, phenyltri-n-butoxysilane, andphenyltriphenoxysilane.

[0050] Examples of alkenylalkoxysilane compounds include vinyltrimethoxysilane,vinyltriethoxysilane, vinyltri-n-propoxysilane, vinyltri-n-butoxysilane,vinyltriphenoxysilane, allyltrimethoxysilane, octenyltrimethoxysilane, anddivinyldimethoxysilane.

[0051] Examples of haloalkoxysilane compounds include trimethoxychlorosilane,triethoxychlorosilane, tri-n-propoxychlorosilane, tri-n-butoxychlorosilane,triphenoxychlorosilane, dimethoxydichlorosilane, diethoxydichlorosilane, di-n-propoxydichlorosilane, diphenoxydichlorosilane, methoxytrichlorosilane,ethoxytrichlorosilane, n-propoxytrichlorosilane, phenoxytrichlorosilane,trimethoxybromosilane, triethoxybromosilane, tri-n-propoxybromosilane,triphenoxybromosilane, dimethoxydibromosilane, diethoxydibromosilane, di-n-propoxydibromosilane, diphenoxydibromosilane, methoxytribromosilane,ethoxytribromosilane, n-propoxytribromosilane, phenoxytribromosilane,trimethoxyiodosilane, triethoxyiodosilane, tri-n-propoxyiodosilane, triphenoxyiodosilane,dimethoxydiiodosilane, di-n-propoxydiiodosilane, diphenoxydiiodosilane,methoxytriiodosilane, ethoxytriiodosilane, n-propoxytriiodosilane, andphenoxytriiodosilane.

[0052] Techniques for preparing functionalized polymers by using hydrocarbyloxy silanecompounds are set forth in U.S. Patent Nos. 3,244,664; 6,008,295; 6,228,908; and4,185,042, which are incorporated herein by reference.

[0053] In one or more embodiments, hydrocarbyloxy silane functionalizing agents is animino-containing hydrocarbyloxy silane that may be defined by the formula:R3R5where R2, R3, and R7divalent organic group, andwhere R5 and R6 are each independently hydrocarbyloxy groups or hydrocarbyl groups.

[0054] In one or more embodiments, the divalent organic group is a hydrocarbylenegroups such as, but not limited to, alkylene, cycloalkylene, alkenylene, cycloalkenylene,alkynylene, cycloalkynylene, or arylene groups. Hydrocarbylene groups include substitutedhydrocarbylene groups, which refer to hydrocarbylene groups in which one or morehydrogen atoms have been replaced by a substituent such as a hydrocarbyl group. In one ormore embodiments, these groups may include from one, or the appropriate minimumnumber of carbon atoms to form the group, to about 20 carbon atoms. These groups may ormay not contain heteroatoms. Suitable heteroatoms include, but not limited to, nitrogen,boron, oxygen, silicon, sulfur, tin, and phosphorus atoms. In one or more embodiments, thecycloalkylene, cycloalkenylene, and arylene groups are non-heterocyclic groups. In these orother embodiments, the substituents forming substituted hydrocarbylene groups are non-heterocyclic groups.

[0055] Examples of these imino-containing hydrocarbyloxy silane compounds includetriethoxy compounds such as, but are not limited to, N-(1,3-dimethylbutylidene)-3-(triethoxysilyl)-1-propaneamine, N-(1-methylethylidene)-3-(triethoxysilyl)-1-propaneamine, N-ethylidene-3-(triethoxysilyl)-1-propaneamine, N-(1-methylpropylidene)-3-(triethoxysilyl)-1-propaneamine, N-(4-N,N-dimethylaminobenzylidene)-3-(triethoxysilyl)-1-propaneamine, and N-(cyclohexylidene)-3-(triethoxysilyl)-1-propaneamine. Other examples include trimethoxy compounds such as, but not limited to,N-(1,3-dimethylbutylidene)-3-(trimethoxysilyl)-1-propaneamine, N-(1-methylethylidene)-3-(trimethoxysilyl)-1-propaneamine, N-ethylidene-3-(trimethoxysilyl)-1-propaneamine, N-(1-methylpropylidene)-3-(trimethoxysilyl)-1-propaneamine, N-(4-N,N-dimethylaminobenzylidene)-3-(trimethoxysilyl)-1-propaneamine, and N-(cyclohexylidene)-3-(trimethoxysilyl)-1-propaneamine. Other examples includemethyldiethoxy compounds such as, but not limited to, N-(1,3-dimethylbutylidene)-3-(methyldiethoxysilyl)-1-propaneamine, N-(1-methylethylidene)-3-(methyldiethoxysilyl)-1-propaneamine, N-ethylidene-3-(methyldiethoxysilyl)-1-propaneamine, N-(1-methylpropylidene)-3-(methyldiethoxysilyl)-1-propaneamine, N-(4-N,N-dimethylaminobenzylidene)-3-(methyldiethoxysilyl)-1-propaneamine, and N-(cyclohexylidene)-3-(methyldiethoxysilyl)-1-propaneamine. Other examples includeethyldimethoxy compounds such as, but not limited to, N-(1,3-dimethylbutylidene)-3-(ethyldimethoxysilyl)-1-propaneamine, N-(1-methylethylidene)-3-(ethyldimethoxysilyl)-1-propaneamine, N-ethylidene-3-(ethyldimethoxysilyl)-1-propaneamine, N-(1-methylpropylidene)-3-(ethyldimethoxysilyl)-1-propaneamine, N-(4-N,N-dimethylaminobenzylidene)-3-(ethyldimethoxysilyl)-1-propaneamine, and N-(cyclohexylidene)-3-(ethyldimethoxysilyl)-1-propaneamine.

[0056] Techniques for preparing functionalized polymers by using imine-containinghydrocarbyloxy compounds are disclosed in U.S. Publication Nos. 2005 / 0009979;2010 / 0113683; and 2011 / 0092633, which are incorporated herein by reference.

[0057] In one or more embodiments, hydrocarbyloxy silane functionalizing agents is ahydrocarbyloxy silane defined by the formula:R5where R4 is a divalent organic group, where R5 and R6 are each independentlygroups or hydrocarbyl groups, R5a monovalent organic group, and A isselected from the group consisting of carboxylic ester, cyclic tertiary amine, non-cyclictertiary amine, pyridine, silazane, and sulfide groups.

[0058] Examples of hydrocarbyloxy silane compounds including a carboxylic ester groupinclude, but are not limited to, 3-methacryloyloxypropyltriethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropylmethyldiethoxysilane,and 3-methacryloyloxypropyltriisopropoxysilane.

[0059] Examples of hydrocarbyloxy silane compounds including a cyclic tertiary aminegroup include, but are not limited to, 3-(1-hexamethyleneimino)propyltriethoxysilane, 3-(1-hexamethyleneimino)propyltrimethoxysilane, (1-hexamethyleneimino)methyltriethoxysilane,(1-hexamethyleneimino)methyltrimethoxysilane, 2-(1-hexamethyleneimino)ethyltriethoxysilane, 3-(1-hexamethyleneimino)ethyltrimethoxysilane,3-(1-pyrrolidinyl)propyltrimethoxysilane, 3-(1-pyrrolidinyl)propyltriethoxysilane, 3-(1-heptamethyleneimino)propyltriethoxysilane, 3-(1-dodecamethyleneimino)propyltriethoxysilane, 3-(1-hexamethyleneimino)propyldiethoxyethylsilane, and 3-[10-(triethoxysilyl)decyl]-4-oxazoline.

[0060] Examples of hydrocarbyloxy silane compounds including a non-cyclic tertiaryamine group include, but are not limited to, 3-dimethylaminopropyltriethoxysilane, 3-dimethylaminopropyltrimethoxysilane, 3-diethylaminopropyltrimethoxysilane, 3-diethylaminopropyltriethoxysilane, 2-dimethylaminoethyltriethoxysilane, 2-dimethylaminoethyltrimethoxysilane, 3-dimethylaminopropyldiethoxymethylsilane, 3-diethylaminopropyldiethoxymethylsilane,3-dimethylaminopropyldimethoxymethylsilane, 3-diethylaminopropyldimethoxymethylsilane, and 3-dibutylaminopropyltriethoxysilane

[0061] Examples of hydrocarbyloxy silane compounds including a pyridine groupinclude, but are not limited to, 2-trimethoxysilylethylpyridine.

[0062] Examples of hydrocarbyloxy silane compounds including a silazane groupinclude, 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.

[0063] Still other specific examples of useful functionalizing agents include trialkyltinhalides such as triisobutyltin chloride, as disclosed in U.S. Patent Nos.4,519,431; 4,540,744;4,603,722; 5,248,722; 5,349,024; 5,502,129; and 5,877,336, which are incorporated hereinby reference. Examples of useful halogenated organic compounds include cyclic aminocompounds such as hexamethyleneimine alkyl chloride, as disclosed in U.S. Patent Nos.5,786,441; 5,916,976; and 5,552,473, which are incorporated herein by reference.Additional examples include cyclic sulfur-containing or oxygen containing azaheterocyclessuch as disclosed in WO 2004 / 020475; U.S. Publication No. 2006 / 0178467; and U.S. PatentNo. 6,596,798, which are incorporated herein by reference. Other examples include boron-containing terminators such as disclosed in U.S. Patent No. 7,598,322, which is incorporatedherein by reference. Still other examples include cyclic siloxanes such ashexamethylcyclotrisiloxane, including those disclosed in U.S. Patent No. 9,920,149, which isincorporated herein by reference. Yet other examples include polydimethylsiloxanes.AMOUNT OF FUNCTIONALIZATION AGENT USED

[0064] The amount of functionalizing employed in the practice of the present inventioncan be described with respect to the lithium or metal cation associated with the initiator. Inone or more embodiments, the amount of functionalizing agent introduced to thepolymerization mixture is greater than 0.70, in other embodiments greater than 0.75, inother embodiments greater than 0.80, in other embodiments greater than 0.85, and in otherembodiments greater than 0.90 moles of functionalizing agent per mole of lithium in theinitiator. In these or other embodiments, less than 0.99, in other embodiments less than0.97, and in other embodiments less than 0.95 moles of functionalizing agent per mole oflithium is introduced to the polymerization mixture. In one or more embodiments, fromabout 0.7 to about 1.0, in other embodiments from about 0.75 to about 0.99, and in otherembodiments from about 0.80 to about 0.97 moles of functionalizing agent per mole oflithium is introduced to the polymerization mixture.FUNCTIONALIZATION REACTION

[0065] The reaction between the respective species of functionalizing agents and thepolymer can take place by introduction the functionalizing agent sequentially orsimultaneously to the reactive polymer.

[0066] In one or more embodiments, the reaction between the functionalizing agent andthe reactive polymer may take place at a temperature from about 10 °C to about 150 °C, andin other embodiments from about 20 °C to about 100 °C. The time required for completingthe reaction between the functionalizing agent and the reactive polymer depends on variousfactors such as the type and amount of the initiator used to prepare the reactive polymer, thetype and amount of the functionalizing agent, as well as the temperature at which thefunctionalization reaction is conducted. In one or more embodiments, the reaction betweenthe functionalizing agent and the reactive polymer can be conducted for about 10 to 60minutes.

[0067] In one or more embodiments, the functionalizing agent is introduced to thepolymer cement (i.e. polymerization mixture) while the polymer is dissolved or suspendedwithin a solvent. As those skilled in the art appreciate, this solution may be referred to as apolymer cement, or more specifically as a reactive or living polymer cement. In one or moreembodiments, the characteristics of the polymer cement, such as its concentration, will bethe same or similar to the characteristics of the cement prior to functionalization. Thecomposition including the functionalized polymer and solvent may be referred to as apolymerization mixture; in other words, a polymerization mixture including a functionalizedpolymer.

[0068] In one or more embodiments, modification of the polymer (i.e., introduction of thefunctionalizing agent to the polymer cement), takes place within the same vessel in whichthe polymerization was conducted. In other embodiments, modification of the polymertakes place outside of the reaction vessel in which the polymerization takes place. Forexample, the first and second functionalizing agents can be introduced to the polymerizationmixture (i.e. polymer cement) in a downstream vessel or a downstream transfer conduit.

[0069] According to one or more embodiments, as a result of the functionalizationreaction, greater than 60 mol %, in other embodiments greater than 70 mol %, in otherembodiments greater than 80 mol %, in other embodiments greater than 85 mol %, in otherembodiments greater than 90 mol %, and in other embodiments greater than 95 mol % ofthe polymer chains within the polymer cement include a terminal functional group (i.e. theresidue of a functionalizing agent). In one or more embodiments, from about 60 to about 100mol %, in other embodiments from about 70 to about 99 mol %, in other embodiments fromabout 80 to about 98 mol %, and in other embodiments from about 90 to about 97 mol % ofthe polymer chains within the polymer composition include the terminal functional group.

[0070] According to one or more embodiments, as a result of the functionalizationreaction, greater than 80 mol %, in other embodiments greater than 90 mol %, in otherembodiments greater than 95 mol %, and in other embodiments greater than 99 mol % ofthe polymer chains within the polymer cement include terminal functional groups at bothends of the polymer (i.e. are telechelic polymers).POST FUNCTIONALIZATION POLYMER STABILIZATION

[0071] In one or more embodiments, following modification, the modified polymer (i.e.the telechelic polymer may optionally be stabilized (i.e. post-functionalization stabilized).That is, the modified polymer may be stabilized by introducing a stabilizing agent to thepolymerization mixture including the modified polymer. It is believed that the stabilizingagent reacts with certain terminal functional groups (e.g. a hydrocarbyloxy substituent), andit is believed that this reaction may take place at the introduction of the two molecules orafter aging of the composition.

[0072] In one or more embodiments, stabilizing agents known in the art may be used.For example, the stabilizing agents may include alkylalkoxy silanes as disclosed in U.S. PatentNo. 6,255,404, which is incorporated herein by reference. Exemplary alkylalkoxy silanesinclude octyltriethoxy silane. In other embodiments, the stabilizing agent may include long-chain alcohols as disclosed in U.S. Patent No. 6,279,632, which is incorporated herein byreference. Exemplary long chain alcohols include sorbitan stearate or sorbitan monoleate.In still other embodiments, the polymers may be stabilized by treatment with an alkylalkoxysilane followed by treatment with a silane including a hydrolyzable group that forms anacidic species upon hydrolysis, such as methyltrichlorosilane, as disclosed in U.S. Patent No.9,546,237, which is incorporated herein by reference.

[0073] In one or more embodiments of this invention, the use of aryl silanols (also knownas hydroxy phenyl silanes) is advantageously used as a stabilizing agent. Useful aryl silanolsare disclosed in U.S. Patent No. 9,255,167, which is incorporated herein by reference.Exemplary aryl silanols include, but are not limited to, triphenylsilanol, which is also referredto as hydroxytriphenylsilane, diphenylsilanediol, which is also referred to asdihydroxydiphenylsilane, and phenylsilanetriol, which is also referred to astrihydroxy(phenyl)silane.

[0074] In one or more embodiments, the functionalized polymers of this invention may bestabilized by treatment with an aryl silanol (e.g. aryl silane diol or aryl silane triol)contemporaneously or followed by treatment with a silane including a hydrolyzable groupthat forms an acidic species upon hydrolysis. Silanes including a hydrolyzable group that forman acidic species upon hydrolysis are disclosed in U.S. Patent No. 9,546,237, which isincorporated herein by reference. In particular embodiments, the functionalized polymers aretreated with diphenyl silane diol and trimethyl silyl chloride.

[0075] In one or more embodiments, the stabilizing agent is added to the polymer cementafter a sufficient time is provided to allow completion of the reaction between the reactivepolymer and the functionalizing agent. In one or more embodiments, the stabilizing agent isintroduced to the polymer cement after 30 minutes, in other embodiments after 15 minutes,and in other embodiments after 10 minutes from the time that the functionalizing agent isintroduced to the polymer cement.

[0076] The amount of stabilizing agent (e.g. aryl silanol) employed in the practice of thepresent invention can be described with respect to the moles of lithium associated with theinitiator. In one or more embodiments, greater than 0.5, in other embodiments greater than1, in other embodiments greater than 2, and in other embodiments greater than 3 moles ofstabilizing agent per mole of lithium in the initiator is introduced to the polymerizationmixture. In these or other embodiments, less than 8, in other embodiments less than 7, inother embodiments less than 6, in other embodiments less than 5, and in other embodimentsless than 4.5 moles of stabilizing agent per mole of lithium is introduced to thepolymerization mixture. In one or more embodiments, from about 1 to about 7, in otherembodiments from about 2 to about 6, and in other embodiments from about 3 to about 5moles of stabilizing agent per mole of lithium is introduced to the polymerization mixture.

[0077] In other embodiments, the amount of stabilizing agent (e.g. aryl silanol) employedin the practice of the present invention can be described as a molar ratio relative to the molesof functionalizing agent employed. In one or more embodiments, the ratio of the moles ofstabilizing agent to the moles of functionalizing agent employed is from about 0.5:1 to about8:1; in other embodiments from about 1:1 to about 7:1, in other embodiment from about 2:1to about 6:1, and in other embodiments from about 3:1 to about 5:1. In these or otherembodiments, the ratio of the moles of stabilizing agent to the moles of functionalizing agentemployed is less than 7:1, in other embodiments less than 6:1, in other embodiments lessthan 5.5:1, in other embodiments less than 5:1, and in other embodiments less than 4.5:1.

[0078] Where two reagents are employed, such as where the polymer is treated with anaryl silanol (e.g. aryl silane diol or aryl silane triol) together with a silane including ahydrolysable group that forms an acidic species upon hydrolysis (e.g. hydrocarbyl silylchloride such as trimethyl silyl chloride), the amount of the respective reagents employedmay be the same or different. In one or more embodiments, the total amount of stabilizeremployed (i.e. both compounds) is, when described as a molar ratio relative to the moles offunctionalizing agent, from about 3:1 to about 10:1, in other embodiments from about 4:1 toabout 8:1, and in other embodiments from about 5:1 to about 7:1. In these or otherembodiments, the molar ratio of the aryl silanol to the silane including a hydrolysable groupthat forms an acidic species upon hydrolysis is from about 0.5:1 to about 4:1, in otherembodiments from about 1:1 to about 3:1, and in other embodiments from about 1.5:1 toabout 2.5:1.

[0079] In one or more embodiments, the stabilization of the polymer (i.e., introduction ofthe stabilizing agent) takes place within the same vessel in which the polymerization tookplace. In these embodiments, this will include the same vessel in which the modification tookplace. In other embodiments, stabilization of the polymer (i.e., introduction of the stabilizingagent) takes place outside of the vessel in which the polymerization took place. Likewise, inone or more embodiments, stabilization of the polymer takes place outside of the vessel inwhich the modification of the polymer took place. For example, in one or moreembodiments, the stabilizing agent can be added to the polymerization mixture (i.e., polymercement) in a vessel or transfer line that is downstream of the vessel in which thepolymerization took place and that is downstream of the vessel in which the polymermodification took place. For purposes of this specification, relative to the polymerizationvessel, the vessel or conduit in which the stabilizing agent is introduced may be referred toas a second vessel or second reaction zone. In other embodiments, the stabilizing agent maybe introduced to the polymer while the polymer is suspended or dissolved within monomer.CONDENSATION ACCELERATOR

[0080] In one or more embodiments, after the introduction of the functionalizing agentto the reactive polymer, optionally after the addition of a quenching agent and / orantioxidant, optionally after or together with the stabilizing agent, and optionally afterrecovery or isolation of the functionalized polymer, a condensation accelerator can be addedto the polymerization mixture. Useful condensation accelerators include tin and / or titaniumcarboxylates and tin and / or titanium alkoxides. One specific example is titanium 2-ethylhexyl oxide. Useful condensation catalysts and their use are disclosed in U.S.Publication No. 2005 / 0159554 (Patent No. US 7,683,151), which is incorporated herein byreference. In other embodiments, an organic acid can be used as a condensation accelerator.Useful types of organic acids include aliphatic, cycloaliphatic and aromatic monocarboxylic,dicarboxylic, tricarboxylic and tetracarboxylic acids. Specific examples of useful organicacids include, but are not limited to, acetic acid, propionic acid, butyric acid, hexanoic acid,2-methylhexanoic acid, 2-ethylhexanoic acid, cyclohexanoic acid and benzoic acid.

[0081] The amount of condensation accelerator employed in the practice of the presentinvention can be described with respect to the moles of lithium associated with the initiator.In one or more embodiments, the moles of condensation accelerator per mole of lithium isgreater than 1.0, in other embodiments greater than 1.5, and in other embodiments greaterthan 1.8 moles of condensation accelerator per mole of lithium in the initiator. In these orother embodiments, less than 4.0, in other embodiments less than 3.3, and in otherembodiments less than 3.0 moles of condensation accelerator per mole of lithium isintroduced to the polymerization mixture. In one or more embodiments, from about 1.0 toabout 4.0, in other embodiments from about 1.5 to about 3.3, and in other embodiments fromabout 1.8 to about 3.0 moles of condensation accelerator per mole of lithium is introducedto the polymerization mixture.ANTIOXIDANT

[0082] In one or more embodiments, after the introduction of the functionalizing agentto the reactive polymer, optionally after the addition of a quenching agent and / orantioxidant, optionally after or together with the stabilizing agent, and optionally afterrecovery or isolation of the functionalized polymer, an antioxidant can be added to thepolymerization mixture. Exemplary antioxidants include 2,6-di-tert-butyl-4-methylphenol.

[0083] In one or more embodiments, after formation of the polymer, a processing aid andother optional additives such as oil can be added to the polymer cement.OPTIONAL QUENCHING

[0084] In one or more embodiments, after the polymerization reaction, or after thereaction between the reactive polymer and the functionalizing agent has been accomplishedor completed, a quenching agent can be added to the polymerization mixture in order toinactivate any residual reactive polymer chains and the catalyst or catalyst components. Thequenching agent may include a protic compound, which includes, but is not limited to, analcohol, a carboxylic acid, an inorganic acid, water, or a mixture thereof. The amount ofquenching agent employed may be in the range of 0.5 to 10 moles of quenching agent permole of lithium used to initiate the polymerization.POLYMER DESOLVENTIZATION

[0085] Following polymerization and / or polymer modification, optional stabilization,optional introduction of a condensation accelerator and / or introduction of an antioxidant,the polymer product can be separated from the solvent, which may be referred to asdesolventization. In other words, as described above, the polymers are synthesized in anorganic solvent, and during the step of desolventization, the organic solvent is separatedfrom the resulting polymer.

[0086] In particular embodiments, desolventization includes hot water and / or steamcoagulation. For example, the polymerization mixture, which includes the blend of modifiedpolymers, can be combined with a steam or hot water stream. The heat associated with thesteam or hot water stream volatilizes the solvent and any unreacted monomer. The polymerproduct is then dispersed within an aqueous phase in, for example, the form of polymercrumb. The nature and size of the polymer crumb can generally be manipulated by theintroduction of mechanical energy (e.g., in the form of mixers).

[0087] In one or more embodiments, the polymer crumb is temporarily stored as a crumbdispersion within the water until subsequent drying steps, which are described below. Thecrumb dispersion is generally a mixture of polymer particles or crumb and water. Thepolymer particles, which may also be referred to as coagulated polymer, are generally on themacroscale and have at least on dimension that is greater than one mm. This crumbdispersion may be contained within a tank, such as a conventional reactor tank such as acontinuously stirred tank reactor.

[0088] In one or more embodiments, the polymer crumb can be further processed toremove residual solvent and dry the polymer (i.e., separate the polymer from the water). Inpracticing the present invention, the polymer can be dried by using conventional techniques,which may include one or more of filtering, pressing, and heating. Following desolventizationand drying, the volatile content of the dried polymer can be below 2.0 %, in otherembodiments below 1.0 %, and in other embodiments below 0.5% by weight of the polymer.

[0089] In other embodiments, the polymer product can be desolventized by employingdevolatilizers, which are extruder-type devices that can operate in conjunction with heatand / or vacuum. In yet other embodiments, the polymerization mixture can be directly drumdried.

[0090] Regardless of the methods used to desolventize and dry the polymer, the finishedpolymer product may be referred to as a dried polymer. Using conventional techniques, thedried polymer can be molded or otherwise manipulated into a bale.CHARACTERISTIC OF LINEAR TELECHELIC POLYMERS

[0091] The functionalized polymers produced according to aspects of the presentinvention may be characterized by Mooney viscosity, which is determined according to byusing a Mooney viscometer (e.g. Agilent viscometer) with a large rotor at 100 °C with a 4minute run time after 1 minute of preheating (i.e. ML 1+4 @ 100 °C). In one or moreembodiments, the functionalized polymers have a Mooney viscosity of greater than 20, inother embodiments greater than 30, and in other embodiments greater than 40. In these orother embodiments, the functionalized polymers have a Mooney viscosity of less than 80, inother embodiments less than 70, and in other embodiments less than 60. In one or moreembodiments, the functionalized polymers have a Mooney viscosity of from about 20 toabout 80, in other embodiments from about 30 to about 70, and in other embodiments fromabout 40 to about 60.

[0092] The functionalized polymers produced according to aspects of the presentinvention may be characterized by a glass transition temperature (Tg), which is determinedaccording to ASTM E1356-08 by using differential scanning calorimetry (DSC) techniques.In one or more embodiments of less than -20, in other embodiments less than -30, and inother embodiments less than -40 °C. In one or more embodiments, the functionalizedpolymers have a Tg of from about -65 to about -30, in other embodiments from about -60 toabout -30, and in other embodiments from about -50 to about -40 °C.INDUSTRIAL APPLICABILITY

[0093] In one or more embodiments, the linear telechelic polymers of the invention maybe used in formulating vulcanizable rubber composition that may, for example, be useful inthe preparation of tire components. Rubber compounding techniques and the additivesemployed therein are generally disclosed in The Compounding and Vulcanization of Rubber,in Rubber Technology (2nd Ed. 1973).

[0094] Generally speaking, these vulcanizable rubber compositions include avulcanizable rubber component, reinforcing filler, and a curative or curative system. Thesecompositions may also optionally include metal activators, resins, and processing oils, aswell the various ingredients that may be conventionally included in these vulcanizablerubber compositions.

[0095] In one or more embodiments, the linear telechelic polymers of this invention mayform all or part of the rubber component of the vulcanizable compositions. That is, therubber component may include other vulcanizable rubbers, which may also be referred toas elastomeric polymers or simply elastomers.

[0096] The rubber compositions can be prepared by using the linear telechelic polymersof this invention alone or together with other elastomers (i.e., polymers that can bevulcanized to form compositions possessing rubbery or elastomeric properties). Otherelastomers that may be used include natural and synthetic rubbers. The synthetic rubberstypically derive from the polymerization of conjugated diene monomers, thecopolymerization of conjugated diene monomers with other monomers such as vinyl-substituted aromatic monomers, or the copolymerization of ethylene with one or more α-olefins and optionally one or more diene monomers.

[0097] Exemplary synthetic rubbers, 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 mixturesthereof. These elastomers can have a myriad of macromolecular structures including linear,branched, and star-shaped structures. Natural rubber is synthesized by and obtained fromplant life. For example, natural rubber can be obtained from Hevea rubber trees, guayuleshrub, gopher plant, mariola, rabbitbrush, milkweeds, goldenrods, pale Indian plantain,rubber vine, Russian dandelions, mountain mint, American germander, and tall bellflower.

[0098] Generally, the rubber compositions of this invention include from about 30 toabout 65, in other embodiments from about 35 to about 60, and in other embodiments fromabout 40 to about 55 weight percent rubber (i.e. the rubber component), based on the totalweight of the tire component, of rubber.

[0099] In one or more embodiments, the rubber component of the rubber compositionsof this invention include from about 1 to about 100 wt %, in other embodiments from about10 to about 90 wt %, and in other embodiments from about 20 to about 80 wt % of thebranched polymers produced by the techniques of this invention.

[0100] As indicated above, the rubber compositions may include fillers such asinorganic 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 clays (hydrated aluminum silicates). Carbonblacks and silicas are the most common fillers used in manufacturing tires. In certainembodiments, a mixture of different fillers may be advantageously employed.

[0101] The amount of total filler employed in the rubber compositions can be up toabout 150 parts by weight per 100 parts by weight of rubber (phr), with about 5 to about125 phr, or about 30 to about 110 phr, being typical. In certain embodiments the total fillercontent is greater than about 100 phr. In other embodiments, the total filler content is fromabout 50 to about 100 phr, and in in further embodiments from about 55 to about 95 phr.

[0102] In one or more embodiments, carbon blacks include furnace blacks, channelblacks, and lamp blacks. More specific examples of carbon blacks include super abrasionfurnace blacks, intermediate super abrasion furnace blacks, high abrasion furnace blacks,fast extrusion furnace blacks, fine furnace blacks, semi-reinforcing furnace blacks, mediumprocessing channel blacks, hard processing channel blacks, conducting channel blacks, andacetylene blacks.

[0103] In particular embodiments, the carbon blacks may have a surface area (EMSA)of at least 20 m2 / g and in other embodiments at least 35 m2 / g; surface area values can bedetermined by ASTM D-1765 using the cetyltrimethylammonium bromide (CTAB)technique. The carbon blacks may be in a pelletized form or an unpelletized flocculent form.The preferred form of carbon black may depend upon the type of mixing equipment used tomix the rubber compound.

[0104] In one or more embodiments, the amount of carbon black employed in therubber compositions can be up to about 75 parts by weight per 100 parts by weight of rubber(phr), with about 5 to about 6 parts by weight phr, or about 10 to about 55 parts by weightphr, being used in exemplary embodiments.

[0105] In one or more embodiments, silicas may be characterized by their surfaceareas, which give a measure of their reinforcing character. The Brunauer, Emmet and Teller(“BET”) method (described in J. Am. Chem. Soc., 1939, vol. 60, 2 p. 309-319) is a recognizedmethod for determining the surface area. The BET surface area of silica is generally less than450 m2 / g. Useful ranges of surface area include from about 32 to about 400 m2 / g, about100 to about 250 m2 / g, and about 150 to about 220 m2 / g. In one or more embodiments, thesilica may be characterized by a pH of from about 5 to about 7 or slightly over 7, or in otherembodiments from about 5.5 to about 6.8.

[0106] In certain embodiments, the silica employed in the rubber composition isderived from rice husk ash only, and in other embodiments the rubber compositions do notinclude silica from non-rice husk ash derived processes.

[0107] Some commercially available silicas which may be used include Hi-SilTM 215, Hi-SilTM 233, and Hi-SilTM 190 (PPG Industries, Inc.; Pittsburgh, Pa.). Other suppliers ofcommercially available silica include Grace Davison (Baltimore, Md.), Degussa Corp.(Parsippany, N.J.), Rhodia Silica Systems (Cranbury, N.J.), and J.M. Huber Corp. (Edison, N.J.).

[0108] In one or more embodiments, the rubber compositions may include from about1 to about 150, in other embodiments from about 5 to about 140, and in other embodimentsfrom about 10 to about 130 parts by weight silica per 100 parts by weight rubber. Inparticular embodiments, the present invention includes rubber compositions with high silicaloadings, such as loadings greater than 70, in other embodiments greater than 90, and inother embodiments greater than 110 parts by weight silica per 100 parts by weight rubber,with the useful upper end being limited by the high viscosity imparted by silica. When silicais used together with carbon black, the amount of the silica or carbon black can be can beas low as about 1 phr. In one or more embodiments, where carbon black and silica areemployed in combination as a filler, the weight ratio of silica to total filler may be fromabout 5% to about 99% of the total filler, or in other embodiments from about 10% toabout 90% of the total filler, or in yet other embodiments from about 50% to about 85% ofthe total filler.

[0109] In one or more embodiments, where silica is employed as a filler (alone or incombination with other fillers), a coupling agent may be added to the rubber compositionsduring mixing in order to enhance the interaction of silica with the elastomers. Usefulcoupling agents are disclosed in U.S. Patent Nos. 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; 5,684,171;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; which are incorporated herein by reference.

[0110] In one or more embodiments, the amount of coupling agent may be from about2 to about 30 wt %, in other embodiments from about 4 to about 25 wt %, and in otherembodiments from about 6 to about 20 wt % based on the weight of silica within thecomposition.

[0111] In one or more embodiments, where silica is employed as a filler (either aloneor in combination with other fillers), a silica dispersing agent, which may include silicashielding agents, may be included in the rubber formulations. The use of one or more silicadispersing agents has been found to be particularly useful in practicing the presentinvention in view of the telechelic polymers and / or high silica loadings. In one or moreembodiments, useful silica dispersing agents include alkyl alkoxysilanes, fatty acid estersof hydrogenated or non-hydrogenated C5 or C6 sugars, polyoxyethylene derivatives of fattyacid esters of hydrogenated or non-C5 or C6 sugars, and esters of polyols,including glycols and polyhydroxy compounds, and mixtures thereof. In particularembodiments, the silica dispersing agent is glycol monostearate. Useful silane dispersingagents are disclosed in U.S. Patent Nos. 6,608,145, 7,799,870, 7,897,661, 8,962,746,9,758,639, 9,951,208, and U.S. Publication Nos.2004 / 0152811, and 2005 / 0070672, whichare incorporated herein by reference.

[0112] In other embodiments, useful silica dispersing agents include metalglycerolates such as zinc glycerolate, calcium glycerolate, and magnesium glycerolate.These compounds are described in greater detail in U.S. Patent Nos. 10,087,306 and11,220,595, and U.S. Publication No. 2021 / 0388188, which are incorporated herein byreference.

[0113] In one or more embodiments, the rubber compositions of the invention mayinclude from about 0.1 to about 30 wt %, in other embodiments from about 1.0 to about 25wt %, in other embodiments from about 3.0 to about 20 wt %, and in other embodimentsfrom about 4.0 to about 10 wt% silica dispersing agent based on the weight of the silicawithin the composition. In one or more embodiments, the rubber compositions includegreater than 3 wt %, in other embodiments greater than 5 wt %, and in other embodimentsgreater than 7 wt % dispersing agent based upon the weight of the silica. In these or otherembodiments, the rubber compositions may include greater than 3 parts by weight, inother embodiments greater than 4 parts by weight, in other embodiments greater than 5parts by weight, and in other embodiments greater than 6 parts by weight silica dispersingagent per 100 parts by weight rubber.

[0114] A multitude of rubber curing agents (also called vulcanizing agents) may beemployed, including sulfur or peroxide-based curing systems. Curing agents are describedin Kirk-Othmer, Encyclopedia of Chemical Technology, Vol. 20, pgs. 365-468, (3rd Ed.1982), particularly Vulcanization Agents and Auxiliary Materials, pgs. 390-402, and A.Y.Coran, Vulcanization, Encyclopedia of Polymer Science and Engineering, (2nd Ed. 1989),which are incorporated herein by reference. Vulcanizing agents may be used alone or incombination.

[0115] Other ingredients that are typically employed in rubber compounding may alsobe added to the rubber compositions. These include accelerators, accelerator activators, oils,plasticizer, waxes, scorch inhibiting agents, processing aids, zinc oxide, tackifying resins,reinforcing resins, fatty acids such as stearic acid, peptizers, and antidegradants such asantioxidants and antiozonants. In particular embodiments, the oils that are employedinclude those conventionally used as extender oils, which are described above. Generally, therubber compositions of this invention can include from about 1 to about 70 parts by weight,or in other embodiments from about 5 to about 50 parts weight total oil per 100 parts byweight rubber.

[0116] All ingredients of the rubber compositions can be mixed with standard mixingequipment such as, but not limited to, Banbury mixers, Brabender mixers, intermesh mixersincluding tandem intermesh mixers, extruders, kneaders, and two-roll mills. In one or moreembodiments, the ingredients are mixed in two or more stages. In the first stage (oftenreferred to as the masterbatch mixing stage), a so-called masterbatch, which typicallyincludes the rubber component and filler, is prepared. To prevent premature vulcanization(also known as scorch), the masterbatch may exclude vulcanizing agents. The masterbatchmay be mixed at a starting temperature of from about 25 °C to about 125 °C with a dischargetemperature of about 135 °C to about 180 °C. Once the masterbatch is prepared, thevulcanizing agents may be introduced and mixed into the masterbatch in a final mixing stage,which is typically conducted at relatively low temperatures so as to reduce the chances ofpremature vulcanization. Optionally, additional mixing stages, sometimes called remills, canbe employed between the masterbatch mixing stage and the final mixing stage. One or moreremill stages are often employed where the rubber composition includes silica as the filler.Various ingredients including the polymers of this invention can be added during theseremills.

[0117] The mixing procedures and conditions particularly applicable to silica-filled tireformulations are described in U.S. Patent Nos. 5,227,425; 5,719,207; and 5,717,022, as wellas European Patent No. 890,606, all of which are incorporated herein by reference. In oneembodiment, the initial masterbatch is prepared by including the polymer and silica in thesubstantial absence of coupling agents and shielding agents.

[0118] The rubber compositions prepared from the polymers of this invention areparticularly useful for forming tire components such as treads, subtreads, sidewalls, bodyply skims, bead filler, and the like. In one or more embodiments, these tread or sidewallformulations may include from about 10% to about 100% by weight, in other embodimentsfrom about 35% to about 90% by weight, and in other embodiments from about 50% toabout 80% by weight of the polymer of this invention based on the total weight of the rubberwithin the formulation.

[0119] Where the rubber compositions are employed in the manufacture of tires, thesecompositions can be processed into tire components according to ordinary tiremanufacturing techniques including standard rubber shaping, molding and curingtechniques. Typically, vulcanization is effected by heating the vulcanizable composition in amold; e.g., it may be heated to about 140 °C to about 180 °C. Cured or crosslinked rubbercompositions may be referred to as vulcanizates, which generally contain three-dimensionalpolymeric networks that are thermoset. The other ingredients, such as fillers and processingaids, may be evenly dispersed throughout the crosslinked network. Pneumatic tires can bemade as discussed in U.S. Patent Nos. 5,866,171; 5,876,527; 5,931,211; and 5,971,046,which are incorporated herein by reference.EXAMPLES

[0120] In order to demonstrate the practice of the present invention, the followingexamples have been prepared and tested. The examples should not, however, be viewed aslimiting the scope of the invention. The claims will serve to define the invention.Experiment I INITIATOR PREPARATION

[0121] 8.1 mL of sec-butyl lithium (sBuLi) and 0.97 mL of diisopropenylbenzene (DIPB)were charged to a small glass bottle. After vigorous shaking, 0.79 mL of triethylamine(NEt3)was charged to the bottle. The bottle was again shaken vigorously and agitated in a50 °C water bath for 2 hours. The resulting initiator (which may be referred to as DiLiinitiator) was either quickly used or refrigerated prior to use.POLYMER SYNTHESIS

[0122] Four large bottles were each charged with 98.7 g of hexanes, followed by 15 g ofstyrene (33 wt %). The bottles were vented and 216.26 g of butadiene (21 wt %) wascharged in each bottle. 0.15 mL of 1.6 M 2,2-di-(2-tetrahydrofuryl)propane was added toeach bottle. Finally, 0.72 mL of the DiLi initiator solution was added to each bottle and thebottles were placed in a 50 °C water bath for 2 hours. After 2 hours, functionalizing agent ascharged to each bottle as provided in Table 1 (except bottle 1). The bottles were again placedin the 50 °C water bath and agitated for 30 minutes. After 30 minutes, 3 mL of IPA / BHT wasadded to each bottle to quench the reaction. The polymers were then coagulated in IPA / BHTand drum dried. As shown in Table I, N,N-bis(trimethylsilyl)-aminopropylmethyldimethoxysilane (APMDMOS), glycidoxypropylmethyldiethoxysilane(GPMDEOS), 3-(1,3-dimethylbutylidene)aminopropyltriethoxysilane (DMBAPTEOS) wereemployed as functionalizing agents.POLYMER TESTING

[0123] The physical properties of the polymers were analyzed by NMR, GPC and DSC.The total nitrogen content analysis was also performed on these polymers. The numberaverage (Mn), weight average (Mw) molecular weights and polydispersity (PDI) weredetermined by gel permeation chromatography (GPC) using a Tosoh Ecosec HLC-8320 GPCsystem and Tosoh TSKgel GMHxl-BS columns with THF as a solvent. The system wascalibrated using polystyrene (PS) standards and referenced to PS and SBR standards. Thestyrene and vinyl content of the polymer was determined by 300 MHz NMR using CDCl3 asthe solvent. Polymer Mooney viscosities were determined using a Monsanto Mooneyviscometer. The ML(1+4) values were measured on a large rotor at 100 °C for 4 minutes witha 1 minute of warm up time. Total nitrogen analysis was performed on (3x) coagulatedsamples using Mitsubishi Chemical Analytech NSX-2100 Elemental Analyzer System.Table I Samples I-1 I-2 I-3 I-4 Functional Group None APMDMOS GPMDEOSGPMDEOS +DMBAPTEOSFunctional Group:Li (eq.) - 1.1 1.1 0.45 + 0.25 Mass Recovered (g)48.1 50.8 48.8 49.3Mn, Base Peak (PS Std) (kg / mol) 216 207 225 198 Mw, Base Peak (PS Std) (kg / mol) 234 224 243 212 Mw / Mn (PS Std) 1.08 1.08 1.08 1.07 Mn, Coupled Peak (PS Std) (kg / mol) -- -- 607 597 Mw, Coupled Peak (PS Std) (kg / mol) -- -- 730 790 Mw / Mn (PS Std) -- -- 1.20 1.32 % Coupling -- -- 22.82 33.31 % Styrene 10.9 13.0 10.8 11.0 % Vinyl 58.2 58.8 57.4 55.9 Tg (°C) -43.05 -43.48 -43.62 -44.9 Nitrogen (ppm) 26 224 -- 52 Silane / chain (Calculated from TN) 0 2 -- -- Experiment II INITIATOR PREPARATION

[0124] 2 eq. of sec-butyl lithium (sBuLi) (1.4 M in cyclohexane) and 1 eq. of neatdiisopropenylbenzene (DIPB) were charged to a small glass bottle. After vigorous shaking,1 eq. of neat trimethylamine (NEt3)was added to the bottle. The bottle was again shakenvigorously and agitated in a 50 °C water bath for 2 hours. The resulting initiator (DiLiinitiator) was either quickly used or refrigerated prior to use.POLYMER PREPARATION – SAMPLE 1

[0125] A steel vessel was charged with 2.64 lb hexanes, 0.45 lbs styrene (33 wt %) and6.68 lb butadiene (21 wt %) under agitation. 1.75 mL of 1.60 M 2,2-di-(2-tetrahydrofuryl)propane solution was then added followed by 8.39 mL of 0.58 M of the DiLiinitiator solution. The jacket temperature was immediately set to 63 °C. The reactionreached a peak temperature of 97.4 °C in about 22 minutes. About 30 minutes after peak,the non-functional polymer was dropped into a solution of IPA / BHT (0.6 g BHT / 100 mL IPA)and coagulated. The coagulated polymer was drum dried and utilized for analyticalevaluation.POLYMER PREPARATION – SAMPLE 2

[0126] A stainless steel jacketed vessel was charged with 2.64 lb hexanes, 0.46 lbstyrene (33 wt %) and 6.68 lb butadiene (21 wt %) 0.99 mL of 1.6 M 2,2-di-(2-tetrahydrofuryl)propane solution was charged to the reactor followed by addition of 2.04mL of 2.50 M n-BuLi solution and the jacket temperature was immediately set to 63 °C. Thereaction reached a peak temperature of 82 °C in about 20 minutes. Fifteen minutes afterpeak exotherm, about 600 mL of cement was dropped in 2 bottles and 3-(1,3-dimethylbutylidene)aminopropylmethyldiethoxysilane (DMBAPDEOS) (1.1 eq / Li) wasadded to each bottle. The bottles were agitated in a 50 °C water bath for 30 minutes. Thepolymer was quenched by adding 3 mL IPA / BHT (0.6 g BHT / 100 mL IPA), coagulated anddrum dried.POLYMER PREPARATION – SAMPLE 3

[0127] A stainless steel jacketed vessel was charged with 3.14 lb hexanes, 0.42 lbstyrene (33 wt %) and 6.22 lb butadiene (21 wt %). 1.83 mL of 1.6 M 2,2-di-(2-tetrahydrofuryl)propane solution was charged to the reactor followed by addition of 9.10mL of 0.58 M DiLi initiator solution and the jacket temperature was immediately set to 63°C. The reaction reached a peak temperature of 102.9 °C in about 20 min. 15 min after peakexotherm 3.69 mL of neat 3-(1,3-dimethylbutylidene) aminopropylmethyldiethoxysilane(DMBAPDEOS) functional group was added to the reactor and the reaction was continuedfor another 30 min. The polymer cement was coagulated by dropping in IPA / BHT (0.6 gBHT / 100 mL IPA) solution and drum dried.POLYMER PREPARATION – SAMPLE 4

[0128] A stainless steel jacketed vessel was charged with 3.14 lb hexanes, 0.42 lbstyrene (33 wt %) and 6.22 lb butadiene (21 wt %). 1.83 mL of 1.60 M 2,2-di-(2-tetrahydrofuryl)propane solution and 9.10 mL of DiLi initiator solution were added to thereactor and the jacket temperature was set at 63 °C. The reaction reached a peaktemperature of 100.5 °C in about 23 minutes. 15 minutes after peak 3.69 mL of neat 3-(1,3-dimethylbutylidene)aminopropylmethyldiethoxysilane (DMBAPDEOS) was added to thereactor and the reaction was continued for another 30 minutes. After 30 minutes, about 650mL of polymer cement was dropped into 10 large bottles and quenched with 3 mL IPA / BHT(0.6 g BHT / 100 mL IPA). The residual polymer cement in the reactor was coagulated inIPA / BHT solution and drum dried for analysis.POLYMER TESTING

[0129] Polymer Samples 1-4 were tested by using the methods provided above and theresults are reported in Table II.Table II Samples II-1 II-2 II-3 II-4 Initiator DiLi n-BuLi DiLi DiLi Functional Group Non-functional DMBAPDEOS DMBAPDEOS DMBAPDEOS 1H NMR% Styrene 11.1 10.5 11.1 10.8 % Vinyl 36.5 39.7 39.2 40.5 GPC Tosoh (PS Std) Base Mn (kg / mol) 195 193 185 170 Base Mw (kg / mol) 223 201 197 192 Base Mp (kg / mol) 214 202 198 200 Mw / Mn 1.14 1.04 1.07 1.13 % Coupling -- 37% 34% 24% Mooney Viscosity ML(1+4)(MU)13 18 34 40T80(s)0.9 1.0 1.5 2.0Total Nitrogen (ppm) 13 79 194 175Experiment III INITIATOR PREPARATION

[0130] A small glass bottle was charged with 6.84 mL of sec-BuLi (1.4 M in cyclohexane)and 0.82 mL diisopropenylbenzene (neat, 5.58 M)(DIPB), the bottle was shaken vigorously,then 0.67 mL triethylamine (NEt3)(neat, 7.17 M) was charged. The bottle was again shakenvigorously then agitated in a 50 °C water bath for 2 hours. The catalyst solution (DiLiinitiator solution) was either quickly used or refrigerated prior to use.POLYMER PREPARATION

[0131] A nitrogen-purged, jacketed stainless-steel reactor was charged with 2.90 lbs ofanhydrous hexanes and 0.45 lbs of 33 weight % styrene in hexanes. The reactor was ventedto 2 psi and 6.43 lbs of 21.0 weight % butadiene in hexanes was charged. 1.92 mL 2,2-bis(2’-tetrahydrofuryl)propane (1.6 M; 0.32 eq vs Li) was added to the reactor followed by thecatalyst solution prepared as described above. The jacket temperature was set to 62.8 °Cand the solution temperature and reactor pressure were monitored via sensors locatedinside the vessel. The batch temperature peaked at 94.7 °C in about 25 minutes. 15 minutesafter peak, 6.5 mL of 3-(1,3-dimethylbutylidene) aminopropyldiethoxysilane (3.1 M, 1 eq VsLi) was added to the reactor and the reaction was continued for another 30 min. Samples ofthe product cement were then collected through a needle into dried, purged, sealed 800 mLbottles. The resulting polymer was characterized as follows: 12.6 % bound styrene, 44.5 %vinyl, Tg = - 55 °C, Mn = 260 kg / mol, Mw 441 kg / mol, Mp = 199 kg / mol, and 44 % coupled.POLYMER STABILIZATION

[0132] The polymer cement in each bottle prepared above was quenched by adding 3mL IPA / BHT solution. Then to each of 2 bottles containing approximately 400g of cementwas added (1) diphenylsilanediol (0.1 M in 20% ethanol in cyclohexane)(DPSDO) and / or (2)triphenylsilanol (0.2 M in 20% ethanol in cyclohexane) (TPS) as shown in Table III. Thebottles were agitated in a 50 °C water bath for 30 minutes. The cement from the bottle pairswas then steam desolventized using a mini-steam desolventizer apparatus. To the water wasadded 15g of polycoat (for Example III-1; the same water was used for subsequent samplesand 8 g of polycoat was added each time) and the water was heated to above 80 °C usingsteam. With the agitator speed set as high as possible without causing splashing, the cementwas poured from the bottles into the desolventizer in a slow, controlled manner resulting incrumbed material. The devolatilized material was collected and dried in an oven at 70 °C for12 hours. A portion of the material was then oven-aged at 100 °C for 48 hours. The unagedpolymer properties were analyzed using the techniques outlined above.Table III Samples III-1 III-2 III-3 III-4 III-5 DPSDO -- 2 4 -- 1 TPS-- -- -- 1 1Total Mass of Cement (g) 795 799 817 819 815 Volume of Stabilizer Added (mL) -- 36 73 9 9 / 18 Unaged Data Gel Content 93% 12% 2% 14% 2% MS(1+4)57.73 40.82 23.84 34.71 39.33T80(s)>900 29.76 8.57 9.89 7.74Aged Data Gel Content 89% 39% 4% 49% 42% MS(1+4)76.54* 88.07 61.33 87.48 87.5 T80 (s) >900 673.92 31.63 428.28 830.6

[0133] Various modifications and alterations that do not depart from the scope andspirit of this invention will become apparent to those skilled in the art. This invention is notto be duly limited to the illustrative embodiments set forth herein.

Claims

CLAIMSWhat is claimed is:

1. A method for preparing a linear telechelic diene copolymer, the method comprising:(i) preparing a dilithium initiator by reacting dialkenyl compound with analkyl lithium compound;(ii) introducing the dilithium initiator, diene monomer, vinyl aromaticmonomer, and a randomizer to form a polymerization mixture;(iii) allowing the diene monomer and vinyl aromatic monomer topolymerize and form a polymer having first and second reactive ends; and(iv) functionalizing both the first and second reactive ends of the polymerby reacting the first and second reactive ends with first and second functionalizingagents to thereby form a linear telechelic diene copolymer.

2. The method of claim 1, where the polyalkenyl compound is diisopropenyl benzene.

3. The method of any of the preceding claims, where the alkyl lithium is selected fromn-butyl lithium, t-butyl lithium, and sec-butyl lithium.

4. The method of any of the preceding claims, where said step of preparing a dilithiuminitiator includes aging the initiator under inert atmosphere at a temperature of fromabout 0 to about 150 ℃ for greater than 15 minutes.

5. The method of any of the preceding claims, where the molar ratio of moles of Liassociated with the alkyl lithium to equivalents of alkenyl groups associated with thedialkenyl compound is from about 1.95:1 to about 2.05:1.

6. The method of any of the preceding claims, where said step of preparing a dilithiuminitiator includes aging the initiator in the presence of a Lewis base.

7. The method of any of the preceding claims, where the Lewis base is selected from thegroup consisting of 2,2-bis(2-oxolanyl)propane (also known as 2,2-ditetrahydrofurylpropane), meso-2,2-diterahydrofurylpropane, DL-2,2,-ditetrahdydrofurlypropane, tetramethylethylenediamine, and mixtures thereof.

8. The method of any of the preceding claims, where the Lewis base trialkyl amine.

9. The method of any of the preceding claims, where said step of preparing a dilithiuminitiator includes aging the initiator within a reaction mixture that includes a solventin which the initiator is soluble.

10. The method of any of the preceding claims, where said step of introducing thedilithium initiator, diene monomer, vinyl aromatic monomer, and a randomizer toform a polymerization mixture takes place with a solvent in which at least one of thedilithium initiator, diene monomer, vinyl aromatic monomer, a randomizer andpolymer are soluble to thereby form a polymerization mixture.

11. The method of any of the preceding claims, where the polymer having first and secondreactive ends is characterized by at least one of an Mp of from about 160 to about 280,an Mn of from about 130 to about 300, and an Mw of from about 180 to about 500.

12. The method of any of the preceding claims, where the polymer having first and secondreactive ends is monomodal and has a molecular weight distribution of less than 2.5.

13. The method of any of the preceding claims, where the polymer having first and secondreactive ends is characterized by a vinyl content of from about 5 to about 80%.

14. The method of any of the preceding claims, where the polymer having first and secondreactive ends is characterized by a bound styrene content of from about 20 to about60 wt%.

15. The method of any of the preceding claims, where the polymer having first and secondreactive ends is characterized by a T80 of less than 2 seconds.

16. The method of any of the preceding claims, where the first and second functionalizingagents are hydrocarbyloxy silanes.

17. The method of any of the preceding claims, where the first and second functionalizingagents are the same type of functionalizing agent.

18. The method of any of the preceding claims, where the first and second functionalizingagents are different types of functionalizing agents.

19. The method of any of the preceding claims, where the first and second functionalizingagents are defined by the formulaR3R5where R2, R3, and R7a divalent organic group,and where R5 and R6 are each independently hydrocarbyloxy groups or hydrocarbylgroups.

20. The method of any of the preceding claims, where one of R5 and R6 is ahydrocarbyloxy group and the other of R5 and R6 is a hydrocarbyl group.

21. The method of any of the preceding claims, where at least one of the first and secondfunctionalizing agent is selected from the group consisting of N-(1,3-dimethylbutylidene)-3-(triethoxysilyl)-1-propaneamine, N-(1-methylethylidene)-3-(triethoxysilyl)-1-propaneamine, N-ethylidene-3-(triethoxysilyl)-1-propaneamine,N-(1-methylpropylidene)-3-(triethoxysilyl)-1-propaneamine, N-(4-N,N-dimethylaminobenzylidene)-3-(triethoxysilyl)-1-propaneamine, and N-(cyclohexylidene)-3-(triethoxysilyl)-1-propaneamine.

22. The method of any of the preceding claims, where at least one of the first and secondthe functionalizing agent is selected from the group consisting of trimethoxycompounds such as, but not limited to, N-(1,3-dimethylbutylidene)-3-(trimethoxysilyl)-1-propaneamine, N-(1-methylethylidene)-3-(trimethoxysilyl)-1-propaneamine, N-ethylidene-3-(trimethoxysilyl)-1-propaneamine, N-(1-methylpropylidene)-3-(trimethoxysilyl)-1-propaneamine, N-(4-N,N-dimethylaminobenzylidene)-3-(trimethoxysilyl)-1-propaneamine, and N-(cyclohexylidene)-3-(trimethoxysilyl)-1-propaneamine.

23. The method of any of the preceding claims, where at least one of the first and secondthe functionalizing agent is selected from the group consisting of methyldiethoxycompounds such as, but not limited to, N-(1,3-dimethylbutylidene)-3-(methyldiethoxysilyl)-1-propaneamine, N-(1-methylethylidene)-3-(methyldiethoxysilyl)-1-propaneamine, N-ethylidene-3-(methyldiethoxysilyl)-1-propaneamine, N-(1-methylpropylidene)-3-(methyldiethoxysilyl)-1-propaneamine,N-(4-N,N-dimethylaminobenzylidene)-3-(methyldiethoxysilyl)-1-propaneamine,and N-(cyclohexylidene)-3-(methyldiethoxysilyl)-1-propaneamine.

24. The method of any of the preceding claims, where at least one of the first and secondthe functionalizing agent is selected from the group consisting of ethyldimethoxycompounds such as, but not limited to, N-(1,3-dimethylbutylidene)-3-(ethyldimethoxysilyl)-1-propaneamine, N-(1-methylethylidene)-3-(ethyldimethoxysilyl)-1-propaneamine, N-ethylidene-3-(ethyldimethoxysilyl)-1-propaneamine, N-(1-methylpropylidene)-3-(ethyldimethoxysilyl)-1-propaneamine,N-(4-N,N-dimethylaminobenzylidene)-3-(ethyldimethoxysilyl)-1-propaneamine,and N-(cyclohexylidene)-3-(ethyldimethoxysilyl)-1-propaneamine.

25. The method of any of the preceding claims, where at least one of the first and secondthe functionalizing agent is defined by the formulaR5where R4 is a divalentand R6 are each independentlygroups or hydrocarbylis a monovalent organic group, andA is selected from the group consisting of, carboxylic ester, cyclic tertiary amine, non-cyclic tertiary amine, pyridine, silazane, and sulfide groups.

26. The method of any of the preceding claims, where at least one of the first and secondthe functionalizing agent is selected from the group consisting of 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.

27. The method of any of the preceding claims, where the monomer is a conjugated dienemonomer and optionally includes a vinyl aromatic monomer.

28. The method of any of the preceding claims, where after said step of functionalizingboth the first and second reactive ends of the polymer by reacting the first and secondreactive ends with first and second functionalizing agents to thereby form a lineartelechelic diene copolymer, a stabilizing agent is introduced to the linear telechelicdiene copolymer.

29. The method of any of the preceding claims, where the stabilizing agent is an arylsilanol.

30. The method of any of the preceding claims, where the amount of aryl silanolintroduced is from about 1 to about 7 moles of aryl silanol per mole of lithiumintroduced to the polymerization mixture.

31. The method of any of the preceding claims, where the aryl silanol is selected from thegroup consisting of triphenylsilanol, diphenylsilanediol, and phenylsilanetriol.

32. The method of any of the preceding claims, where after said step of functionalizingboth the first and second reactive ends of the polymer by reacting the first and secondreactive ends with first and second functionalizing agents to thereby form a lineartelechelic diene copolymer, an aryl silanol and a silane including a hydrolyzable groupthat forms an acidic species upon hydrolysis is introduced to the linear telechelicdiene copolymer.

33. The method of any of the preceding claims, where the molar ratio of the aryl silanolto the silane with a hydrolyzable group that forms an acidic species upon hydrolysisis from about 0.5:1 to about 4:1.

34. The method of any of the preceding claims, further comprising the step of isolatingthe linear telechelic polymer from the polymerization mixture.

35. A linear telechelic polymer formed by the method of any of the preceding claims.

36. A vulcanizable composition of matter including the linear telechelic polymer of anyof the preceding claims.

37. A vulcanizate prepared by vulcanizing the vulcanizable composition of matter of anyof the preceding claims.

38. A tire component prepared from the vulcanizable composition of any of the precedingclaims.

39. A tire tread prepared from the vulcanizable composition of any of the precedingclaims.

40. The method of any of the preceding claims, where the molar ratio of the aryl silanolto the silane with a hydrolyzable group that forms an acidic species upon hydrolysisis from about 0.5:1 to about 4:1.

41. A vulcanizable composition comprising:(i) a linear telechelic diene copolymer prepared by:(a) preparing a dilithium initiator by reacting dialkenyl compound withan alkyl lithium compound;(b) introducing the dilithium initiator, diene monomer, vinyl aromaticmonomer, and a randomizer to form a polymerization mixture;(c) allowing the diene monomer and vinyl aromatic monomer topolymerize and form a polymer having first and second reactive<sub>ends; and(d) functionalizing both the first and second reactive ends of thepolymer by reacting the first and second reactive ends with first andsecond functionalizing agents to thereby form a linear telechelicdiene copolymer;(ii) silica; and(iii) a curative.

42. The vulcanizable composition of any of the preceding claims, further comprising asilica coupling agent.

43. The vulcanizable composition of any of the preceding claims, further comprising asilica dispersing agent.

44. The vulcanizable composition of any of the preceding claims, where the silicadispersing agent is selected from the group consisting of alkyl alkoxysilanes, fatty acidesters of hydrogenated or non-hydrogenated C5 or C6 sugars, polyoxyethylenederivatives of fatty acid esters of hydrogenated or non-hydrogenated C5 or C6 sugars,and esters of polyols, and mixtures thereof.

45. The vulcanizable composition of any of the preceding claims, where the silicadispersing agent is glycol monostearate.

46. The vulcanizable composition of any of the preceding claims, where the silicadispersing agent is a metal glycerolate.

47. The vulcanizable composition of any of the preceding claims, where the metalglycerolate is zinc glycerolate.

48. The vulcanizable composition of any of the preceding claims, where the vulcanizablecomposition includes greater than 70 parts by weight silica per 100 parts by weightrubber.

49. The vulcanizable composition of any of the preceding claims, where the vulcanizablecomposition includes from about 2 to about 30 wt % silica coupling agent based uponthe weight of the silica.

50. The vulcanizable composition of any of the preceding claims, where the vulcanizablecomposition includes from about 0.1 to about 30 wt % silica dispersing agent basedupon the weight of the silica.

51. A vulcanizate prepared by vulcanizing the vulcanizable composition of matter of anyof the preceding claims.

52. A tire component prepared from the vulcanizable composition of any of the precedingclaims.

53. A tire tread prepared from the vulcanizable composition of any of the precedingclaims.

54. A method for forming a vulcanizable composition, the method comprising:(i) providing a linear telechelic diene copolymer prepared by:(a) preparing a dilithium initiator by reacting dialkenyl compound withan alkyl lithium compound;(b) introducing the dilithium initiator, diene monomer, vinyl aromaticmonomer, and a randomizer to form a polymerization mixture;(c) allowing the diene monomer and vinyl aromatic monomer topolymerize and form a polymer having first and second reactiveends; and(d) functionalizing both the first and second reactive ends of thepolymer by reacting the first and second reactive ends with first andsecond functionalizing agents to thereby form a linear telechelicdiene copolymer;(ii) providing silica;(iii) providing a curative; and(iv) mixing the linear telechelic diene copolymer, silica, and curative toform the vulcanizable composition.

55. The method of any of the preceding claims, further comprising providing a silicacoupling agent; and further comprising mixing the branched polymer, silica, and silicacoupling agent.

56. The method of any of the preceding claims, further comprising providing a silicadispersing agent; and further comprising mixing the branched polymer, silica, andsilica dispersing agent.

57. The method of any of the preceding claims, further comprising providing a silicacoupling agent and a silica dispersing agent; and further comprising mixing the lineartelechelic diene copolymer, silica, and silica dispersing agent, and silica couplingagent.

58. The method of any of the preceding claims, where the silica dispersing agent isselected from the group consisting of alkyl alkoxysilanes, fatty acid esters ofhydrogenated or non-hydrogenated C5 or C6 sugars, polyoxyethylene derivatives offatty acid esters of hydrogenated or non-hydrogenated C5 or C6 sugars, and esters ofpolyols, and mixtures thereof.

59. The method of any of the preceding claims, where the silica dispersing agent is glycolmonostearate.

60. The method of any of the preceding claims, where the silica dispersing agent is a metalglycerolate.

61. The method of any of the preceding claims, where the metal glycerolate is zincglycerolate.

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