MXPA99007948A - Rim that runs desinfl - Google Patents

Abstract

Deflated tires are usually made to include a rigid insert on the side of the tire. This insert must be as rigid as possible to help support the weight of the vehicle in which the tire is mounted in situations where there is a loss of air pressure. However, the material used to make the insert must also exhibit low hysteresis and must be capable of processing. This highly beneficial combination of properties is achieved by using the compositions of this invention to make deflated tire insert parts. This invention discloses a deflated tire consisting of a cover frame generally in toroidal shape with an outer circumferential tread band, and two separate beads, at least one layer extending from heel to heel and lateral sides extending radially from and connecting the tread with the heels, where the tread is adapted to contact with. the terrain wherein the lateral sides contain at least one insert radially inward from the layer and wherein the insert consists of (1) a cured polydiene rubber which is coupled with an Iva Group metal that is selected from the group consisting of tin, lead, germanium and silicon, (2) from about 30 phr to about 130 phr of a filler or filler and (3) from 0. 1 phr to 5 phr of a fatty acid. The insert will generally extend radially inward from below the outer circumferential tread toward the heel toward which the sidewall extends. It is usually preferred that the cured polydiene rubber be coupled with the latter.

Description

"RIM THAT RUNS DEFLATED" TECHNICAL FIELD This invention relates to a pneumatic tire that is capable of being used after the total loss of air pressure, other than ambient atmospheric pressure. In other words, the tire can be used in a deflated condition.

BACKGROUND OF THE INVENTION Several tire constructions have been suggested for pneumatic tires that run flat; that is, tires that can be used while they are deflated (with total loss of air pressure other than ambient air pressure). A vehicle equipped with these tires may continue to be driven after the tire experiences loss of pneumatic pressure, such as loss of air pressure caused by puncture or valve failure. This is highly desirable since it allows vehicles equipped with these flat tires to continue running until they reach a place where the tire can be repaired or replaced safely.

- - One approach for manufacturing a flat tire that runs flat is described in US Patent Number 4,111,249 which is referred to as "Banded Rim". This approach involves providing a ring or annular band directly below and approximately as wide as the running surface. The rim in combination with the rest of the rim structure is disclosed as being capable of supporting the weight of the vehicle, while the rim is in a deflated condition. This banded tire actually tenses the ropes of the coat even when it is in a deflated state. Another approach described in European Patent Publication No. 0-475-258A1 is simply to reinforce the sidewalls of the rim by increasing the cross-sectional thickness thereof. When these tires are operated in the deflated condition, place the sidewalls of the tire in compression. Heat build-up can lead to tire failure in these rims due to the large amounts of rubber required to provide rigidity to the sidewall in cases where this approach is taken. This is especially the case when the rim is operated for extended periods at high speeds in the deflated condition.

- - U.S. Patent No. 5,368,082 discloses the first commercially acceptable pneumatic radial pneumatic radial tire rim, the Eagle® GSC-EMT tire introduced by The Goodyear Tire & Rubber Company. This rim was accepted as an equipment option for a 1994 Corvette Chevrolet car. U.S. Patent No. 5,368,082 discloses the use of special sidewall insertion parts to improve stiffness. Approximately 2.72 kilograms of weight per tire were required to sustain a load of 363.20 kilograms on this flat tire. These tires that run deflated had a very low elongation. This prior invention, even though it is superior to previous attempts, still imposes a weight penalty per rim that could be counteracted by the removal of a spare tire and the jack from the rim. This weight penalty was even more problematic when engineers tried to build taller rims for large luxury passenger sedans. The required weight for a luxury flat tire is approximately 635.60 kilograms of cargo. These rims with higher sidewalls that have elongations within the range of 55 percent to 65 percent or greater mean that the workloads were several times greater than that of the tires that run - - flat 40 percent elongation developed for the Corvette car. These loads meant that the lateral sides of the total rim had to be rendered rigid to the point of compromising the march. Owners of luxury vehicles simply will not sacrifice ride quality for the ability to run flat. The aim of the engineering has been to develop a tire that runs flat without compromising the running or operation. In sports cars that have suspension characteristics, relatively rigid, the ability to provide this tire that runs flat was comparatively easy compared to providing these tires for luxury sedans that demand smoother ride characteristics. Light truck sport utility vehicles, even when they are not as sensitive for running operation, typically use tires that have a relatively high elongation that makes the requirements for the flat tire running more demanding. An equally important design consideration in the development of a flat rim is to ensure that the flat tire remains seated in the rim. Solutions have been developed that employ heel restraining devices as well as special flanges to achieve this requirement. Alternatively, the Eagle GSC-EMT rim employed a new bead configuration allowing the rim to run on normal flanges without requiring additional bead restraining devices. U.S. Patent Number 5,427,166 and the US Patent Number 5,511,599 disclose tires wherein a third layer and a third insert on the sidewall are used to further increase the performance of the tire running flat by a basic design disclosed in US Pat. 5,368,082. These patents disclose the concept of including additional layers and inserts on a sidewall of the rim to achieve improved performance characteristics of the flat tire running flat. U.S. Patent Number ~ 5, 685, 927 discloses a flat tire that provides a higher elongation with the use of load bearing bead cores positioned directly below the belt pack of the running surface of the tire. tire. The tires that run deflated manufactured using this approach are very promising in load support and ride quality. However, this approach leads to higher rolling resistance which decreases fuel economy even during periods when the tire is used under normal conditions under normal inflation pressure. U.S. Patent No. 5,535,800 discloses the use of composite ribs covered with an elastomeric material which in combination with the radial layer can provide excellent deflated belt capacity over a wide range of rim applications. Tin-coupled polymers are known to provide desirable properties, such as improved tread surface wear and reduced rolling resistance, when used in tread rubbers. These tin-coupled rubber polymers are typically manufactured by coupling the rubber polymer with a tin coupling agent at or near the end of the polymerization used to synthesize the rubber polymer. In the coupling process, the ends of the active polymer chain react with the tin coupling agent, thereby coupling the polymer. For some cases, up to four active chain ends can react with tin tetrahalides, such as tin tetrachloride, thereby coupling the polymer chains together. The coupling efficiency of the tin coupling agent depends on many factors, such - as the number of active chain ends available for coupling and the amount of polar modifier type, if any, that is used in the polymerization. For example, tin-bonding agents are generally not as effective in the presence of polar modifiers. The amount of coupling that is also achieved, of course, depends greatly on the amount of the tin coupling agent employed. Each tin tetrahalide molecule is able to react with the four active polymer chain ends. However, since perfect stoichiometry is difficult to achieve, some of the tin halide molecules frequently react with fewer than four active polymer chain ends. For example, if more than one stoichiometric amount of the tin halide coupling agent is employed, there will be an insufficient amount of active polymer chain ends to fully react with the tin halide molecules on a four to one basis. On the other hand, if less than a stoichiometric amount of the tin halide coupling agent is added, there will be an excess of active polymer chain ends and some of the active chain ends will not be coupled. Conventional tin coupling results in the formation of a coupled polymer that is essentially symmetrical. In other words, all arms of the polymer in the coupled polymer are essentially of the same chain length. All arms of the polymer in these conventional tin-coupled polymers consequently have essentially the same molecular weight. This results in conventional tin-coupled polymers which have a low polydispersity. For example, conventional tin-coupled polymers typically having a weight average molecular weight ratio to number average molecular weight that falls within the range of 1.01 to about 1.1. U.S. Provisional Patent Application Number 60 / 037,929, filed on Feb. 14, 1997, discloses that greatly improved properties for tire tires such as lower hysteresis can be achieved by asymmetrically coupling the rubber. For example, these asymmetrically coupled polymers can be used to make tires that have greatly improved rolling resistance without sacrificing other properties of the rim. These improved properties are due in part to the better interaction and compatibility with carbon black. The symmetrical tin coupling also normally leads to improved characteristics of cold flow rubber polymer. Tin coupling in general also leads to better processing capacities and other beneficial properties. The asymmetric tin-coupled rubber polymers that can be used to improve the performance characteristics of the tread surface compounds of the rim consist of a tin atom having polydiene arms covalently linked thereto. At least one of the polydiene arms linked to the tin atom will have a low molecular weight arm having a number average molecular weight of less than about 40,000. It is also critical for the asymmetric tin coupled rubber polymer having at least one high molecular weight polydiene arm attached to the tin atom. This high molecular weight arm will have a number average molecular weight that is at least 80,000. The ratio of the weight average molecular weight to the number average molecular weight of the asymmetric tin-coupled rubber polymers of this invention will also be within the range of about 2 to about 2.5. U.S. Provisional Patent Application Serial Number 60/037, 929 further discloses a process for preparing rubber polymers coupled with - asymmetric tin comprising: (1) continuously polymerizing at least one diene monomer at a conversion of at least about 90 percent, using an anionic initiator to produce a polymer cement containing active polydiene rubber chains where some of the active polydiene rubber chains are low molecular weight polydiene rubber chains having a number average molecular weight of less than about 40,000, and wherein some of the active polydiene rubber chains are rubber chains of high molecular weight polydiene having a number average molecular weight of more than about 80,000; and (2) continuously adding a tin halide to the polymer cement in a separate reaction vessel to produce the asymmetrically tin-coupled rubber polymer wherein this symmetrical tin-coupled rubber polymer has a polydispersity that falls within the scale of approximately 2 to approximately 2.5. In accordance with the Patent Application U.S. Provisional Serial Number 60 / 037,929, the stability of the asymmetric tin-coupled rubber polymers can be improved by adding tertiary chelation amine thereto subsequent to the time at which the rubber polymer coupled with - Tin is coupled. N, N, N ', N' -tetramethylethylenediamine (TMEDA) is a representative example of a tertiary chelating amine which is preferred for use in the stabilization of these asymmetric tin-coupled rubber polymers. However, there is a desire to further improve the stability of these asymmetric tin-coupled rubber polymers.

COMPENDIUM OF THE INVENTION This invention discloses flat tires that can be built without appreciably increasing the weight or rolling resistance. These flat running tires are manufactured using an insert that consists of (1) a cured polydiene rubber that couples with a Group IVa metal selected from the group consisting of tin, lead, germanium and silicon, (2) from about 30 phr to about 130 phr of a filler or filler and (3) from 0.1 phr to 5 phr of a fatty acid. The insert will generally extend radially inwardly from beneath the outer circumferential running surface toward the bead toward which the sidewall extends. It is usually preferred that the cured polydiene rubber be coupled to the tin. In any case, the inserts manufactured using this composition offer higher levels of modulus. This means that the thickness of the insert can be reduced, which lowers the level of heat accumulation and hysteresis experienced. Therefore, the inserts of this invention can be used to manufacture tires that run flat and offer reduced rolling resistance and heat buildup through the flat running rims manufactured with conventional inserts. The weight of the flat running rims manufactured using the thinner insert parts of this invention is reduced because the thinner insert shells naturally weigh less. This reduction in weight is of course an advantage that can lead to better vehicle performance and fuel economy. The use of thinner inserts also leads to reduced rim material cost. The highest level of filler or filler that is used in the inserts of the rim of this invention also leads to reduced cost. However, the highest filler loading level does not normally lead to increased hysteresis or increased polymer viscosity. The total cost of tire production can also be reduced due to - - what - the times Healing cycle can be reduced because the insert piece is thinner. It should further be noted that the rim inserts of this invention can be used successfully in a wide variety of alternative shell frame constructions. This invention more specifically discloses a pneumatic tire having at least one insert to provide the pneumatic tire with deflated running capacity. These rims use, as the insert, a composition of matter consisting of (1) a cured polydiene rubber which is coupled to a Group IVa metal which is selected from the group consisting of tin, lead, germanium and silicon, (2) from about 20 phr to about 130 phr of a filler or filler and (3) from 0.1 phr to 5 phr of a fatty acid. The present invention also discloses a deflated running tire consisting of a generally toroidal-shaped tire frame with an outer circumferential ride surface, two separate heels, at least one layer extending from heel to heel and side sides. that extend radially from and that connect the running surface with the heels; wherein the running surface is adapted to contact the ground, wherein the lateral sides contain at least one insert radially inward from the layer and wherein the insert consists of (1) a rubber of cured polydiene which is coupled with a member selected from the group consisting of tin, lead, germanium and silicon, (2) from about 20 phr to about 130 phr of a filler or filler and (3) from 0.1 phr to 5 phr of a fatty acid. The present invention further discloses a pneumatic radially deflated running tire having a rolling surface, two non-extensible annular beads, a tire frame comprising a radial layer structure having at least one radial layer, radial layer structure having at least one radial layer, a belt structure positioned between the tread band and the radial layer structure and two lateral sides reinforced by one or more inserts, wherein the inserts consist of (1) a cured polydiene rubber which is coupled to a Group IVa metal selected from the group consisting of tin, lead, germanium and silicon, (2) from about 20 phr to about 130 phr of a filler or filler and (3) from 0.1 phr to 5 phr of a fatty acid; wherein the rim is characterized by: (a) a tread surface having tread ribs positioned laterally; (b) a sidewall rib positioned near the radially outer region of each sidewall adapted for contact with a drive surface during the running operation that is deflated and free of contact with the drive surface during normal inflation pressure operation; (c) first decoupling grooves disposed circumferentially between the lateral side rib and the adjacent tread rib; and (d) second decoupling grooves disposed circumferentially between the tread ribs and the adjacent center region of the running surface. The present invention also discloses a pneumatic deflated tire rim comprising a toroidal shell frame and an outer circumferential tread surface designed to contact the ground, wherein the tire frame consists of two non-extensible bead portions. separated, two separate lateral sides each extending radially inwardly from and connecting the running surface with the heel portions and at least one cord-reinforced layer extending from heel to heel and through the sides - - lateral; wherein an essentially crescent-shaped rubber insert is placed in juxtaposition with and axially inward of at least one of the layers of the cover frame of each of the lateral sides of the rim; and wherein the rubber composition of the insert consists of (1) a cured polydiene rubber that couples with a Group IVa metal that is selected from the group consisting of tin, lead, germanium and silicon, (2) from about 30 phr to about 130 phr of a filler or filler and (3) from 0.1 phr to 5 phr of a fatty acid.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a fragmentary cross-sectional view of a rim showing its running surface and the cover frame in one layer and an insert axially inward of the layer in the lateral side region of the rim as an embodiment of the invention. Figure 2 is a fragmentary cross-sectional view of a rim showing its running surfaces and its cover frame with two layers, a second insert interposed between the layers and - - a second layer axially outwardly from the most inward layer in the region of the rim side cover as an embodiment of the invention. Figure 3 is a fragmentary cross-sectional view of a rim showing its running surface and its cover frame with three layers, insertion parts between the layers and another insertion piece axially inward of the inner layer of the region of side cover of the rim, as a modality of the invention.

DEFINITIONS "Axial" and "axially" when used mean the directions that are parallel to the axis of rotation of the rim. "Heel portion" generally means that part of the rim comprising a non-extensible annular tension member such as a multiplicity of annular wires surrounded by an elastomeric composition (s) and which is associated with retaining the rim in the rim that it is wound by the ropes of the reconfigured layer, with or without other reinforcement elements such as apexes, fins or filling materials, thumb guard. The heel core usually refers to the heels of - - wire of the heel portion, but sometimes it may be preferred to the heel portion itself. "Belt structure" or "reinforcement belts" where they are used mean at least two annular layers of parallel woven or non-woven ropes that lie below the running surface, not anchored in the heel and having bead angles both left and right within the scale of 17 ° to 27 ° with respect to the equatorial plane of the rim. "Circumferential" may be used in the description to relate to an address extending along (around) the outer perimeter of the surface of the rim deck framework, such as, for example, the circumferential tread surface in the rim shell. cover. "Deck frame" means the structure of the rim in addition to the tread surface, but which includes support layers, side covers and heels or heel portions. "Scraper" when used herein, refers to thin strips of material placed around the outside of the bead to protect the bead layers from the bead and distribute the friction above the bead.

- - "Rope" means one of the reinforcing ropes of which the layers of the rim consist. "Inner lining" when used herein means the layer or layers of elastomer or other material that form the inner surface of a tube-free rim and that contains the fluid of inflation within the rim. "Layer" means a layer of parallel strings coated with rubber. "Radial" and "radially" means directions radially toward or away from the axis of rotation of the rim. "Radial layer rim" if used herein means a pneumatic tire banded as circumferentially restricted where at least one layer has strings extending from bead to bead that are placed at rope angles between 65 ° and 90 ° with respect to the equatorial plane of the tire. "Shoulder" if used herein means the upper portion of the lateral side just below the edge of the running surface. "Side side" means that portion of the rim between the running surface and the heel.

DETAILED DESCRIPTION OF THE INVENTION - The inserts of the rim of this invention consist of (1) a cured polydiene rubber which is coupled with tin, lead, germanium or silica, (2) a filler and (3) a fatty acid. The composition of the rim insert will typically contain about 30 phr (parts by weight per one hundred parts of rubber) up to about 130 phr of the filler material and from 0.1 phr to about 5 phr of fatty acid. Typically it is preferred that the tire insert compound contains about 60 phr to about 110 phr of the filler material, and about 0.4 phr to about 3 phr of the fatty acid. In general, it is especially preferred that the insert of the rim contains approximately 70 phr to 100 phr of the filler material and from 0.5 phr to 1.5 phr of the fatty acid. The filler material will normally be carbon black, silica or a combination of carbon black and silica. The fatty acid can be virtually any fatty acid that is soluble in the coupled rubber. In most cases, it is preferred to use a mixture of fatty acids due to economic reasons. For example, a preferred mixture of fatty acids includes 40 percent to 50 percent oleic acid, 30 percent to 40 percent linoleic acid, 2 percent to 6 percent "acid". stearic, from 2 percent to 6 percent of rosin acids and from 10 percent to 20 percent of other fatty acids. The fatty acids which can normally be used will be of the formula R-COOH, where R represents an alkyl group or an unsaturated hydrocarbon containing from about 16 to about 20 carbon atoms. In addition, the coupled polyene rubber, the insert may further consist of natural rubber. In some cases, it is advantageous to use a mixture containing about 70 phr of natural rubber based on the total amount of rubber in the mixture. The coupled polydiene rubber can be manufactured by anionic polymerization wherein the polymerization is terminated by the addition of a Via Group metal coupling agent, such as tin tetrahalide. The anionic polymerization is carried out for a sufficient period of time to allow essentially complete polymerization of the monomers. In other words, the polymerization is carried out normally until high conversions are achieved. Then, the coupling agent is added to couple the active rubber polymer which, of course, terminates the polymerization.

- - The coupling agent will typically be Group IVa metal halide, such as tin halide, a lead halide, a germanium halide or a silicon halide. The halogen in the coupling agent will typically be fluorine, chlorine, bromine or iodine. In most cases, the halogen will be selected from the group consisting of fluorine, chlorine and bromine, with chlorine being preferred. Tin coupling agents such as tin tetrachloride, tin tetrabromide, tin tetrachloride and tin tetraiodide, are usually preferred. The coupling agent will normally be a tetrahalide. However, trihalides and dihalides can also be used. In cases where tin dihalides are used, it results in a linear polymer instead of a star polymer. To induce a higher level of branching, tin tetrahalides are usually preferred. Broadly and exemplarily, a scale of about 0.01 to 4.5 millieguivalents of coupling agent per 100 grams of rubber monomer is employed. It is usually preferred to use from about 0.01 to about 1.5 millieguivalents of the coupling agent per 100 grams of monomer to obtain the desired Mooney viscosity. Larger amounts tend to result in the production of polymers containing terminally reactive groups or insufficient coupling. One equivalent of the tin coupling agent per lithium equivalent is considered an optimum amount for maximum branching. For example, if tin tetrahalide is used as the coupling agent, one mole of tin tetrahalide would be used per four moles of active lithium termini or terminals. In cases where a tin trihalide is used as the coupling agent, one mole of tin trihalide will be optimally used for every three moles of the active lithium end (s). The tin coupling agent can be added to a polymer cement containing the active rubber polymer in a hydrocarbon solution e.g. Hexane, with appropriate mixing for distribution and reaction. The coupled rubber polymer used in the rim insertion compositions of this invention can optionally be coupled asymmetrically. A technique for preparing tin-occupied rubber polymers asymmetrically is disclosed in US Patent Application Serial No. 09 / 008,716, filed on January 19, 1998, the teachings of which are incorporated herein by reference in its entirety In this process, the asymmetrically tin-coupled rubber polymer that has - Improved stability is made by a process comprising: (1) continuously polymerizing in a first reactor at least one diene monomer to a conversion of at least about 90 percent, using an anionic initiator to produce a polymer cement containing active polydiene rubber chains; (2) continuously feeding the polymer cement produced in the first reactor to the second reactor; (3) adding a tin halide to the polymer cement in a second reactor under stirring conditions to produce a polymer cement having the tin halide dispersed homogeneously therein wherein the residence time in the second reactor is left within the range of about 15 minutes to about 4 hours, (4) continuously feeding the polymer cement having the tin halide homogeneously dispersed therein in a plug flow reactor having a residence time of about 15 minutes to about 1 hour in order to produce a polymer cement of the asymmetrically tin-coupled rubber polymer, and (5) continuously remove the polymer cement from the rubber polymer asymmetrically coupled with tin from the plug flow reactor. Virtually any type of rubber polymer prepared by anionic polymerization can be - fit asymmetrically with tin. Rubber polymers that can be asymmetrically coupled will typically be synthesized by a solution polymerization technique using an organolithium compound as the initiator. These rubber polymers will therefore normally contain an "active" lithium chain terminal. The polymerizations employed by synthesizing the active rubber polymers will normally be carried out in a hydrocarbon solvent which may be one or more aromatic, paraffinic, cycloparaffinic compounds. These solvents usually contain 4 to 10 carbon atoms per molecule and will be liquid under the conditions of polymerization. Some representative examples of suitable organic solvents include pentane, isooctane, cyclohexane, methylcyclohexane, isohexane, n-heptane, n-octane, n-hexane, benzene, toluene, xylene, ethylbenzene, diethylbenzene, isobutylbenzene, petroleum ether, kerosene, vapors, petroleum, petroleum naphtha and the like, alone or as a mixture. In the solution polymerization, there will usually be from 5 percent to 30 percent by weight of monomers in the polymerization medium. These polymerization media, of course, consist of the organic solvent and the monomers. In most cases you will prefer - - that the polymerization medium contains from 10 percent to 25 percent by weight of monomers. It is more generally preferred that the polymerization medium contain from 15 percent to 20 percent by weight of monomers. The rubber polymers that will normally be asymmetrically coupled can be made by homopolymerization of a conjugated diolefin monomer, or by copolymerization of a conjugated olefin monomer with a vinyl aromatic monomer. Of course it is also possible to manufacture active rubber polymers which can be coupled with the tin asymmetrically by polymerizing a mixture of diolefin monomers conjugated with one or more of the ethylenically unsaturated monomers, such as the vinyl aromatic monomers. The conjugated diolefin monomers which can be used in the synthesis of rubber polymers which can be asymmetrically coupled with tin, according to this invention, will generally contain from 4 to 12 carbon atoms. Those containing 4 to 8 carbon atoms are usually preferred for commercial purposes. Due to similar reasons, 1,3-butadiene and isoprene are the conjugated diolefin monomers most commonly used. Some additional conjugated diolefin monomers that can be used include 2,3-dimethyl-l, 3-butadiene, - piperylene, 3-butyl-l, 3-octadiene, 2-phenyl-1,3-butadiene and the like, alone or as a mixture. Some representative examples of the ethylenically unsaturated monomers that can potentially be synthesized in the rubber polymers that can be asymmetrically coupled with tin, according to this invention include alkyl acrylates such as methyl acrylate, ethyl acrylate, butyl acrylate, methacrylate methyl and the like; the vinylidene monomers having one or more CH2 = CH-terminal groups; aromatic vinyl compounds such as styrene, alpha-methylstyrene, bromostyrene, chlorostyrene, fluorostyrene and the like; alpha-olefins such as ethylene, propylene, 1-butene and the like; vinyl halides such as vinyl chloride, chloroethane (vinyl chloride), vinyl fluoride, vinylidene, 1,2-dibromoethene, 1,1-dichloroethene (vinylidene chloride), 1,2-dichloroethene and the like; vinyl esters such as vinyl acetate, alpha, beta-olefinically unsaturated nitriles such as acrylonitrile and methacrylonitrinyl; alpha, beta-olefinically unsaturated amides such as acrylamide, N-methyl acrylamide, N, N-dimethylacrylamide, methacrylamide and the like. Rubber polymers that are copolymers of one or more diene monomers with one or more ethylenically unsaturated monomers will normally contain from about 50 weight percent to about 99 weight percent conjugated diolefin monomers and about 1 weight percent weight to about 50 weight percent of the other ethylenically unsaturated monomers in addition to the conjugated diolefin monomers. For example, copolymers of diolefin monomers conjugated to vinylaromatic monomers such as styrene-butadiene rubbers containing from 50 percent to 95 percent by weight of conjugated diolefin monomers and from 5 percent to 50 percent by weight of Vinyl aromatic monomers are useful in many applications. Vinyl aromatic monomers are probably the most important group of ethylenically unsaturated monomers that are commonly incorporated in polydienes. These vinyl aromatic monomers are of course selected in order to be copolymerizable with the conjugated diolefin monomers that are being used. Generally, any vinyl aromatic monomer known to polymerize with organolithium initiators may be used. These aromatic vinyl monomers typically contain from 8 to 20 carbon atoms. Usually, the vinyl aromatic monomer will contain from 8 to 14 carbon atoms. Vinyl aromatic monomer more extensively - used is styrene. Some examples of vinyl aromatic monomers that can be used include styrene, 1-vinylnaphthalene, 2-vinylnaphthalene, alpha-methylstyrene, 4-phenylstyrene, 3-methylstyrene and the like. Some representative examples of polymers of the nature of the rubber that can be tin symmetrically coupled in accordance with this invention include polybutadiene, polyisoprene, styrene-butadiene rubber (SBR), alpha-methylstyrene-butadiene rubber, alpha-methylstyrene-rubber isoprene, styrene-isoprene-butadiene rubber (SIBR), styrene-isoprene rubber (SIR), isoprene-butadiene rubber (IBR), alpha-methylstyrene-isoprene-butadiene rubber and alpha-methylstyrene-styrene-isoprene rubber -butadiene. The polymerizations employed to make the polymer of the nature of the rubber are initiated by adding an anionic initiator, such as an organometallic compound of a Group I or Group II metal to an organic polymerization medium containing the monomers. The polymerization is carried out by continuously adding the monomers, the initiator and the solvent to the first polymerization reactor with the first of the nature of the synthesized rubber being continuously removed. This polymerization results in the production of chains of - active polydiene rubber. This polymerization step can be carried out in a single reactor or in a multiple reactor system. The initiator will typically be an organometallic compound of a Group I metal or an organometallic compound of a Group II metal. For example, the initiator can be an organolithium compound, an organosodium compound, an organopotassium compound, an organoubium compound, an organocesium compound, an organoeryllium compound, an organomagnesium compound, an organocalcium compound, a organostronium or an organo-organ compound. The initiator will preferably be an organolithium compound, a organocarbon compound, an organosodium compound, an organopotassium compound or an organomagnesium compound. The organolithium compounds are usually the especially preferred initiators. Organolithium initiators that can be used to synthesize polymers of the nature of rubber that can be asymmetrically coupled in accordance with this invention, include the monofunctional and multifunctional types for polymerizing the monomers described herein. The multifunctional organolithium initiators can either be specific organolithium compounds or they can be of the following types - multifunctionals which are not necessarily specific compounds but rather represent reproducible compositions of adjustable functionality. The amount of the organolithium initiator used will vary with the monomers that are being polymerized and with the molecular weight that is desired for the polymer to be synthesized. However, as a general rule, 0.01 to 1 phm (parts per 100 parts by weight of monomer) of an organolithium initiator will be used. In most cases, 0.01 to 0.1 phm of an organolithium initiator will be used, preferably using 0.025 to 0.07 phm of the organolithium initiator. The selection of the initiator can be regulated by the degree of branching and the degree of elasticity desired for the polymer, the nature of the feedstock and the like. With respect to the feedstock employed as the source of conjugated diene, for example, types of the multifunctional initiator are generally preferred when a diene stream of low concentration is at least a portion of the feedstock since some components present in the Unreacted low-level diene stream may tend to react with the carbon lithium bonds to deactivate the activity of the initiator, thus necessitating the - - presence of sufficient lithium functionality in the initiator in order to overcome these effects. Multifunctional initiators which may be used include those prepared by reacting an organomonolithium mixed with a multivinylphosphine or with a multivinylsilane, such as the reaction being carried out, preferably, in an inert diluent such as a hydrocarbon or a mixture of a hydrocarbon. and a polar organic compound. The reaction between the multivinylsilane or the multivinylphosphine and the organomonolithium compound can result in a precipitate which can be solubilized, if desired, by adding a solubilizing monomer such as a conjugated diene or a monovinyl aromatic compound, after the reaction of the primary components. Alternatively, the reaction can be carried out in the presence of a small amount of the solubilizing monomer. The relative amount of the organomonolithium compound and the multivinylsilane or the multivinylphosphine preferably should be within the range of about 0.33 to 4 moles and the organomonolithium compound per mole and the vinyl groups present in the multivinylsilane or multivinylphosphine used. It should be noted that these multifunctional initiators are commonly used as mixtures of compounds instead of specific individual compounds.

- - Exemplary organomonolithium compounds include ethyl lithium, isopropyl lithium, n-butyl lithium, secondary butyl lithium, tertiary octyl lithium, n-eicosyl lithium, phenyllithium, 2-naphthyl lithium, 4-butylphenyl- lithium, 4-tolyl-lithium, 4-phenylbutyl-lithium, cyclohexyl-lithium and the like. Exemplary multivinylsilane compounds include tetravinylsilane, methyltrivinylsilane, diethyldivinylsilane, di-n-dodecylvinylsilane, cyclohexyltrivinylsilane, phenyltrivinylsilane, benzyltrivinylsilane, (3-ethylcyclohexy) (3-n-butylphenyl) divinylsilane and the like. Exemplary multivinylphosphine compounds include trivinylphosphine, methyldivinylphosphine, dodecyldivinylphosphine, phenylenedivinylphosphine, cyclooctyldivinylphosphine and the like. Other multifunctional polymerization initiators can be prepared using an organomonolithium compound, further together with a multivinylaromatic compound and either a conjugated diene or a monovinylaromatic compound or both. These ingredients can be charged initially, usually in the presence of a hydrocarbon or a mixture of a hydrocarbon and a polar organic compound, as a diluent. Alternatively, a multifunctional polymerization initiator can be prepared in a two-step process by reacting the organomonolithium compound with a conjugated diene or an additive of the monovinyl aromatic compound and then adding the multivinyl aromatic compound. Any of the conjugated dienes or monovinyl aromatic compounds described may be employed. The ratio of the conjugated diene or the additive of the monovinyl aromatic compound preferably used should be within the range of about 2 to 15 moles of the polymerizable compound per mole of the organolithium compound. The amount of the multivinylaromatic compound preferably used should be within the range of about 0.05 to 2 moles per mole of the organomonolithium compound. Exemplary multivinyl aromatic compounds include 1,2-divinylbenzene, 1,3-divinylbenzene, 1,4-divinylbenzene, 1,2,4-trivinylbenzene, 1,3-divinylnaphthalene, 1,8-divinylnaphthalene, 1,3,5 -trivinylnaphthalene, 2,4-divinylbiphenyl, 3,5,4'-trivinylbiphenyl, m-diisopropenylbenzene, p-diisopropenylbenzene, 1,3-divinyl-4,5,8-tributylnaphthalene and the like. Divinyl aromatic hydrocarbons containing up to 18 carbon atoms per molecule are preferred, particularly divinylbenzene either as the ortho, meta or para isomer and commercial divinylbenzene, which is a mixture of the three isomers, and other compounds - such as ethylstyrenes, is also quite satisfactory. Other types of multifunctional initiators may be employed such as those prepared by contacting an organomonolithium compound secondary to tertiary with 1,3-butadiene, at a ratio of 2 to 4 moles of the organomonolithium compound per mole of 1,3-butadiene, in the absence of added polar material in this case, with the contact being carried out preferably in an inert hydrocarbon diluent, even when the contact without the diluent can be used if desired. Alternatively, the specific organolithium compounds can be used as initiators if desired in the preparation of polymers according to the present invention. This can be represented by R (Li) x, where R represents a hydrocarbyl radical containing from 1 to 20 carbon atoms and wherein X is an integer from 1 to 4. The exemplary organolithium compounds are methyl lithium, isopropyl-lithium, n-butyl-lithium, secondary butyl-lithium, tertiary-octyl-lithium, n-decyl-lithium, phenyl-lithium, 1-naphthyl-lithium, 4-butyl-phenyl-lithium, p-tolyl-lithium, 4- phenylbutyl lithium, cyclohexyl lithium, 4-butylcyclohexyl lithium, 4-cyclohexylbutyl lithium, dilithiomethane, 1,4-dilithiobutane, 1, 10-dilithiodecane, 1,20-dilithioeicosane, 1,4-dilithiocyclohexane, 1, 4 dilithium-2-butane, - - 1, 8-dilithio-3-decene, 1,2-dilithio-l, 8-diphenyloctane, 1,4-dilithiobenzene, 1,4-dilithylaphthalene, 9,10-dilithioanthracene, 1,2-dilithiole, 2- diphenylethane, 1, 3, 5-trilithiopentane, 1, 5, 15-trilithioeicosane, 1, 3, 5-trilithiocyclohexane, 1, 3, 5, 8-tetralithiodecane, 1,5,10, 20-tetralithioeicosane, 1,2,4,6-tetralithiocyclohexane, 4,4'-dithio biphenyl and the like. The polymerization temperature used can vary over a wide range from about -20 ° C to about 180 ° C. In most cases, a temperature within the range of about 30 ° C to about 125 ° C will be used. It is typically preferred that the polymerization temperature is within the range of about 60 ° C to about 85 ° C. The pressure used will normally be sufficient to maintain an essentially liquid phase under the conditions of the polymerization reaction. The polymerization in the first reactor is carried out under stirring conditions such as stirring for a sufficient period of time to allow essentially complete polymerization of monomers. In other words, polymerization is usually carried out until high conversions are achieved. For example, - the monomer conversion achieved in the polymerization reactor with the polymerization reactors will typically be greater than about 90 percent. Typically, it will be preferred that the monomer conversion achieved in the first reactor reaches at least about 95 percent with conversions in excess of 98 percent, being especially preferred. Polymerization in the first reactor or series of stirred polymerization reactors results in the formation of a polymer cement containing active polydiene rubber chains. This polymer cement of the polymer of the rubber nature is then fed continuously into a second reactor. A tin halide is also continuously fed into the second reactor. The polymerization is terminated by the continuous addition of a tin coupling agent in the second reactor. The tin coupling agent can be added in a hydrocarbon solution (e.g. in cyclohexane) to the polymerization mixture with appropriate mixing for distribution and reaction. The residence time in the second reactor will be within the range of about 15 minutes, up to about 4 hours. It is usually preferred that the residence time in the second reactor be within the range of about 30 minutes to about 2 hours.

It is usually especially preferred that the residence time in the second reactor be within the range of about 45 minutes to about 90 minutes. The tin coupling agent will usually be a tin tetrahalide, such as tin tetrachloride, tin tetrabromide, tin tetrafluoride or tin tetraiodide. However, tin trihalides may optionally be used. In cases where tin trihalides are used, a coupled polymer having a maximum of three arms results. To induce a higher level of branching, tin tetrahalides are usually preferred. As a general rule, tin tetrachloride is especially preferred. Broadly, and in exemplary manner, a scale of about 0.01 to 4.5 milliequivalents of the tin coupling agent per 100 grams of the polymer of the nature of the rubber is employed to achieve the desired level of symmetric coupling. It is usually preferred to use from about 0.01 to about 1.5 milliequivalents of the tin coupling agent per 100 grams of the polymer to obtain the desired Mooney viscosity. Larger amounts tend to result in the production of polymers containing terminally reactive groups or insufficient coupling. An equivalent of the tin coupling agent per lithium equivalent is considered an optimum amount for maximum branching. For example, if a tin tetrahalide is used as the coupling agent, one mole of tin tetrahalide would be used per four moles of the active lithium terminals. In cases where a tin trihalide is used as the coupling agent, one mole of tin trihalide can be used optimally for every three moles of active lithium terminals. The tin coupling agent can be added in a hydrocarbon solution (e.g. in cyclohexane) to the polymerization mixture in the reactor, with appropriate mixing for distribution and reaction. The polymer cement having the tin halide dispersed homogeneously therein is continuously removed from the second reactor after the desired residence time. It is then continuously fed to a plug flow reactor having a residence time of about 15 minutes to about 1 hour to produce a polymer cement of the polymer of the asymmetrically tin-coupled rubber nature. The plug flow reactor will preferably have a dwell time that is within the range of about 20 minutes to 45 minutes, and will especially preferably have a - stay time that is within the range of approximately 25 minutes to 35 minutes. The plug flow reactor is characterized by the flow of fluid through the reactor which is essentially ordered without a fluid element that mixes with any other fluid element in front of or behind it. Actually there may be lateral mixing of the fluid in a plug flow reactor; however, it essentially must not have mixed or diffused along the flow path. The sufficient necessary condition for the plug flow is so that the residence time in the reactor is equal for all the elements of the fluid passing through it. It should be noted that plug flow reactors are sometimes referred to as slow flow reactors, piston flow reactors, ideal tubular reactors or non-mixed flow reactors. The polymer cement of the polymer of the rubber nature asymmetrically coupled with tin, of course, is continuously removed from the plug flow reactor. Then, a stopping and antioxidant material is typically added to the polymer cement. A 1,2-ethylene tertiary-gelled allyl diamine can optionally be added to the polymer cement to further stabilize the polymer of the asymmetrically tin-coupled rubber nature. The tertiary chelating amines that can be used are usually alkyl chelating diamines of the structural formula: R2 R ~ wherein n represents an integer from 1 to about 6, wherein a represents an alkylene group containing from 1 to about 6 carbon atoms and wherein RI, R ^, R3 and R4 may be the same or different and represent groups of alkyl containing from 1 to about 6 carbon atoms. The alkylene group A is the formula - (~ CH2-) m, where m is an integer from 1 to about 6. The alguylene group will typically contain from 1 to 4 carbon atoms (m will be from 1 to 4) and preferably it contains 2 carbon atoms. In most cases, n will be an integer from 1 to about 3, with n preferred being 1. It is preferred that R - * -, R ^, R3 and R4 represent alkyl groups containing from 1 to 3 carbon atoms. carbon. In most cases R ^, R ^, R3 and R will represent methyl groups. A sufficient amount of the chelation amine must be added to form a complex with any residual tin coupling agent remaining after completion of the coupling reaction. In most cases, polymer cement of about 0.01 phr (parts by weight per 100 parts by weight of dry rubber) will be added to about 2 phr of the chelating alkyl 1,2-ethylenediamine to the polymer cement. stabilize the polymer of the nature of rubber. Typically from about 0.05 phr to about 1 phr of the 1,2-ethylene diamine chelating alkyl will be added. More typically, about 0.1 phr to about 0.6 phr of the 1,2-ethylene diamine chelating alkyl will be added to the polymer cement to stabilize the polymer of the nature of the rubber to the polymer cement. The polymer of the nature of the rubber coupled with asymmetric tin can be recovered from the organic solvent using conventional techniques. For example, the polymer of the nature of the rubber coupled with asymmetric tin can be recovered from the organic solvent and the residue by decanting, filtration, centrifugation and the like. It is often desirable to precipitate the polymer of the asymmetrically tin-coupled rubber nature and the organic solvent by the addition of lower alcohols containing from about 1 to about 4 carbon atoms to the polymer solution. Lower alcohols suitable for precipitation of rubber from polymer cement - they include methanol, ethanol, isopropyl alcohol, normal propyl alcohol and tertiary butyl alcohol. The use of lower alcohols to precipitate the polymer of the asymmetrically tin-coupled rubber nature of the polymer cement also "exterminates" any remaining active polymer by inactivating the lithium end groups. After the polymer of the nature of the rubber coupled with tin is asymmetrically recovered from the solution, steam scrubbing can be employed to reduce the level of volatile organic compounds in the polymer of the asymmetrically tin-coupled rubber nature. The polymers of the asymmetric coupled rubber nature of this invention consist of a Group IV metal having at least three polydiene arms covalently linked thereto. At least one of the polydiene arms bonded to the Group IVa metal has a number average molecular weight of less than about 40,000 and at least one of the polydiene arms attached to the Group IVa metal has a number average molecular weight. of at least approximately 80,000. The ratio of the weight average molecular weight to the number average molecular weight of the polymer of the nature of the rubber coupled with tin - Asymmetric will also be within the range of approximately 2 to approximately 2.5. The asymmetric tin-coupled rubber nature polymers that can be used in the practice of this invention are of the structural formula: R3 I R1-Sn-R2 I R4 wherein R1, R2, R3 and R4 may be the same or different and are selected from the group consisting of alkyl groups and polydiene arms (polydiene rubber chains) with the proviso that at least three members are selected from the group group of R ^, R2, R3 and R4 are polydiene arms, with the understanding that at least a number selected from the group consisting of R1, R2, R3 and R ^ is a low molecular weight polydiene arm which has a number average molecular weight of less than about 40,000 with the understanding that at least one member selected from the group consisting of R 1, R 2, R 3 and R 4 is a high molecular weight polydiene arm having a number average molecular weight greater than about 80,000 and with the proviso that the weight average molecular weight ratio of - - The number average molecular weight of the polymer of the nature of the rubber coupled with asymmetric tin is within the range of about 2 to about 2.5. It should be noted that R ^, R2, R3 and R4 can be alkyl groups because it is possible for the tin halide coupling agent to react directly with the alkyl lithium compounds that are used as the polymerization initiator. In most cases, four polydiene arms will be covalently ligated to the tin atom in the polymer of the asymmetric tin-coupled rubber nature. In these cases, R ^, R2, R3 and R4 will be all polydiene arms. The nature polymer of the asymmetric tin-coupled rubber frequently contains a polydiene arm of intermediate molecular weight as well as a low molecular weight arm and the high molecular weight arm. These intermediate molecular weight arms will have a molecular weight that is within the range of about 45,000 to about 75,000. It is usually preferred that the low molecular weight polydiene arm have a molecular weight of less than about 30,000, it being especially preferred that the low molecular weight arm have a molecular weight of less than about 25,000. It is usually preferred that the high-polydiene arm molecular weight has a molecular weight greater than about 90,000, it being especially preferred that the high molecular weight arm have a molecular weight greater than about 100,000. The rims containing the inserts of the invention may consist of a toroidal shell frame and an outer circumferential tread surface designed for contact with the ground where the cover frame consists of two separate non-extensible bead portions, two lateral sides spaced apart individually extending radially inwardly from and connecting the running surface with the bead portions and at least one layer of cord reinforcement extending from heel to heel and through the lateral sides; an improvement wherein the essentially half-moon shaped rubber insert is placed in juxtaposition with and axially inward of at least one of the layers of the cover frame on each of the sidewalls of the rim. It should be noted that the insert is sulfur co-cured with the rim assembly of the running surface and the roof framework as a whole. Preferably, the insertion piece (s) has a maximum thickness at a site more or less in the middle of the - heel portions and the rolling surface of the lateral side region of the rim. In the practice of this invention, a significant function of the insert on the basis of the rubber composition in the sidewall portion of the rim is to provide rigidity / support the structure of the sidewall when the rim is operated without pressure. inflation. The inserts based on the rubber composition are elastomeric in nature having an essentially half-moon cross-sectional shape and material properties that are selected to improve the inflation running performance, while the durability of the flat tire is promoted. The inserts, if desired, can also be reinforced individually with ropes or short fibers. Therefore, one or more of these inserts can be reinforced in this way. The shape of the inserts is described as being essentially crescent in its configuration. This is also intended to include a truncated crescent shape, particularly, wherein the truncated portion of the crescent insert is placed in juxtaposition with respect to the bead portion of the rim.

- - In the further practice of the invention, the rim cover framework can have from one to three layers comprising a first axially internal layer and optionally one or two additional layers as a second layer and a third layer, respectively, each additional layer it is positioned in axially outward sequence from the first layer in the region of the sidewall of the rim. Furthermore, according to this invention, the rim contains in its cover frame, a first axially internal layer and a second axially external layer from the first layer; wherein the insert is placed in juxtaposition with respect to and axially inwardly of the first layer, in the lateral side region of the rim. Furthermore, according to this invention, the rim contains in its cover frame, a first axially internal layer and a second axially external layer; wherein one of the insert pieces is placed in juxtaposition and is interposed between the first and second layers, in the lateral side region of the rim. Furthermore, in accordance with this invention, the rim contains in its cover frame, a first axially internal layer and a second axially external layer, wherein one of the insert parts is placed in - - juxtaposition with respect to and interposed between the first layer and second layers, in the lateral side region of the rim and other of the insertion parts is placed in juxtaposition, with respect axially inward of the first layer, in the side region side of the rim. In accordance with this invention, further, the rim contains in its cover frame, a first axially internal layer, a second axially external layer from the first layer and a third axially external layer from the second layer, wherein the insert is placed in juxtaposition with respect to axially inwardly of the first layer, in the lateral side region of the rim. Furthermore, according to this invention, the rim contains in its cover frame, a first axially internal layer, a second axially external layer from the first layer and a third axially external layer from the second layer; wherein the insert is placed in juxtaposition and interposed between (a) the first and second layers and / or (b) the second and third layers, in the lateral side region of the rim. Furthermore, in accordance with this invention, the rim contains in its cover frame, a first axially internal layer, a second axially external layer - from the first layer and a third axially external layer from the second layer; wherein the insert is placed in juxtaposition with respect to, and interposed between (a) the first and second layers and / or (b) the second and third layers, in the lateral side region of the rim and also a insertion piece placed in juxtaposition with respect to and axially inward of the inner layer of the layers. In one embodiment, the inner layer or inner layers have synthetic or textile cords reinforcement of polyester, nylon, rayon or aramid, preferably rayon or nylon; while the outer layer preferably has an aramid rope reinforcement, carbon fiber, glass fiber or metal cord reinforcement, preferably brass and / or zinc-coated steel cords. Therefore, in a preferred embodiment, the first layer has rayon or nylon reinforcement cords, an aramid fiber and the second and additional layers are steel cords. The term "layer" is intended to include inserts reinforced with cord that do not extend entirely from a core of the heel to the opposite heel core. However, it is proposed that at least one layer should extend from the core of the heel to the opposite heel core, preferably a radial layer. A second - - The layer may extend from a bead core to just laterally below one or more of the reinforcement belts of the belt structure. In one aspect, the outer layer preferably has cords of a higher modulus (i.e., steel cords) and the inner ply or layers have cords of a lower modulus (i.e., of nylon or rayon). At least one layer, preferably the inner layer extended from the bead core to the bead cord and wound around the bead core. Alternatively, when two or more layers are used, at least one of the additional layers while extending from the bead core to the bead core, does not actually wrap around the bead core. Referring to the drawings, Figures 1, 2 and 3, replace the fragmentary cross section of a rim 1, its running surface 2, the heel portion 3, the lateral side or lateral side region 4, the non-extensible wire bead core 5, the scraper 6 rubber, the thumb rubber protector 7, the rubber composition interchange 8, the belt structure 9 which remains below a portion of the running surface 2, the layer 10 of the cover frame, the frame layer of cover turned upwards 11, the insert 12 and the apex 13.

- - The cords for use in the cover frame layers may consist of one (monofilament) to multiple twisted filaments. The number of filaments in total in the cord can vary from 1 to 13. The cords, particularly the metal cords of the cover frame are generally oriented in such a way that the rim in accordance with the present invention is that which is commonly made reference as a radial tire. The steel rope of the deck frame layer intersects the equatorial plane (EP) of the rim at an angle within the range of 75 ° to 105 °. Preferably, the steel cords intersect at an angle of 82 ° to 98 °. An especially preferred scale is from 89 ° to 91 °. The first and second reinforcing layer structures each may comprise a single layer; however, any number of layers of the cover frame can be used. As further illustrated in the figures, the first layer structure has a pair of upturned ends respectively that wind around each bead core 5 of the bead portion 3 of the cover frame. The ends 11 of the second layer 10 lie in proximity to the bead core 5 and terminate radially adjacent to either side of the core 5 - - of heel, above the bead core 5 or can be wound around the bead core 5 and terminates radially below the upturned end 11 of the first layer 10, as shown. The turned-up ends 11 of the first layer 10 are wound around the second ends of the layer and the bead core 5. The upturned ends of the first layer 11 end radially at a distance above the diameter of the nominal rim of the rim 1 in proximity to the radial location of the width of the maximum section of the rim. In a preferred embodiment, the upturned ends are placed within 20 percent of the height of the rim section from the radial location of the width of the maximum section, most preferably ending at a radial location of the width of the section maximum. The bead core 5 is preferably constructed of a single continuously wound steel or monofilament wire. Positioned within the bead region 3 and the radially internal portions of the lateral side portions 4 are the high modulus elastomeric apex insertion pieces placed between the reinforcing structure 11 and the cover frame and the ends 11 turned upwards , respectively. The elastomeric apex insertion pieces 13 extend from the - - radially outer portion of the heel portions respectively up to the lateral side portion gradually decreasing the width in cross section. The elastomeric apex inserts 13 terminate at a radially outer end. Insert pieces 12 may extend from each bead region radially to the edge of the tread surface usually until just below the reinforcement belt structures 9. As illustrated in the figures, the lateral side portions can each include a first insert 12 and a second insert 12 and still a third insert 12 piece. The first inserts 12 are placed as described in FIG. foregoing. The second insert pieces 12 are placed (interposed) between the first and second layers 10, respectively. The second insert 12 extends from each bead region 3 or portion radially outward to the edge of the running surface 2, namely to just below the reinforcing belt structure 9. In one embodiment, the first insertion pieces 10 each have a thickness in their maximum thickness of at least three percent of the maximum section height "SH" in a location approximately radially aligned with the width of the maximum section of the tire.

- - The second insert and the third insert, if used, have a thickness in their maximum thickness and at least one and one and a half percent (1.5 percent) of the height of the maximum section of the rim in the Location radially above the width of the maximum section of the rim. In a preferred embodiment, the second elastomeric inserts and the third insert if each is used have a thickness of about one and one and one-half percent (1.5 percent) of the height SH of the maximum section of the rim at a radial location of approximately 75 percent of the height of the SH section. For example, in a high-performance tire of size P275 / 40ZR17 this thickness of the second insertion piece of the rim is equal to 2 millimeters. In the location approximately radially aligned with the location of the width of the maximum section of the rim, the thickness of the second insert is 1.3 millimeters. The total thickness of the cross section of the combination of elastomeric inserts that precede the bead portions and the radial location of the width (SW) of the maximum section is preferably of constant thickness. The total thickness of the sidewall and roof framework is at least 11.5 millimeters at the maximum section width location and increases to one - total thickness in the region where it melts in the shoulder near the edges of the lateral running surface. Preferably, the total thickness of the sidewall in the shoulder region of the rim is at least one hundred percent (100 percent) of the total sidewall thickness in the width of the maximum section (SW). This relationship means that the sidewall can be made considerably thinner than the flat tires that run from the previous type. As discussed above, the rim of the present invention has at least one layer having one end 11 turned up (wrapped around the bead core 5) while another layer can simply be terminated adjacent to the bead core 5 without being rolled up actually around the heel core 5. The first insert 12 is preferably made of elastomeric material. The first insert 12 is designed to prevent the sidewall of the rim from collapsing when it operates without any inflation pressure. The insert 12 can be of a scale of Shore A Hard Shore A hardness of about 50 to very hard Shore A of about 95. As a general rule, with the more rigid material, similar operation can be achieved with the Insert piece that has a thinner cross section. The second insert 12 and the third insert 12, if used, may be of the same or different material of physical properties relative to the first insert. This means that the combination of the second insert 12 hard and / or the third insert 12 if used with a first or softer insert 12 is proposed as well as the combination of a first hard insert 12 with a second and / or third insert 12 softer. The elastomeric materials of the second insert may be similar within the Shore A scale of 50 to 95. The second insert 12 and the third insert 12 if used, as shown in the Figures, are manufactured from an elastomeric material. These inserts 12 can be used in multiples of insert pieces interposed between the adjacent layers when more than two layers are used in the structure of the cover frame. The second insert 12 and the third insert 12, when used, act as a separator between the adjacent layers. The ropes of the layers, particularly the radially outer layer are - It puts in tension when the tire is operated deflated. In practice, the rubber compositions for the inserts 12 used in this invention for the construction of the aforementioned pneumatic tire, are preferably characterized by physical properties that improve their use in the invention which are jointly believed to constitute a deviation of the properties of the rubber compositions normally used on the lateral sides of the pneumatic rim, particularly the combination of inserts 12 with the layers 10 having a combination of high stiffness, either different or similar, with hysteresis properties, essentially low. In particular, for the purposes of this invention, the aforementioned inserts 12 are designed to have a high degree of stiffness while having a relatively low hysteresis for this degree of stiffness. This allows the benefits of the change in the modules of the reinforcing cords to be fully appreciated. The rigidity of the rubber composition for the insert 12 is desirable for stiffness and dimensional stability of the sidewall 4 of the rim. A similar stiffness of the rubber composition for the - - Layer for one or more of the layers is desirable for dimensional stability of the tire cover frame including its side sides since it extends across both lateral sides and through the crown portion of the rim. However, it should be appreciated that rubber with a high degree of stiffness in pneumatic tires is normally expected to generate excessive internal heat during service connections (operating in a vehicle running under a load and / or without inflation pressure). internal), particularly when rubber stiffness is achieved by a rather conventional method of simply increasing its carbon black content. This generation of internal heat within the rubber composition typically results in a temperature increase of rigid rubber, and associated rim structures that can potentially be detrimental to the useful life of the rim 1. The hysteresis of the rubber composition it is a measure of its tendency to generate internal heat under service conditions. Speaking without relative terms, a rubber with a lower hysteresis property generates less internal heat under service conditions than an otherwise comparable rubber composition with a considerably higher hysteresis. Therefore, in - - In one aspect, a relatively low hysteresis is desirable for the rubber composition for the filler or filler materials and the cap (s) for one or more of the layers 10. Hysteresis is a term for the thermal energy that is inverted in a material (eg cured rubber composition) by applied work and low hysteresis of a rubber composition indicated by a relatively high bounce and relatively low tan delta property values (Tan Delta). Accordingly, it is important that the rubber compositions for one or more of the inserts 12 and layers for one or more of the layers 10 have the properties of relatively high stiffness and low hysteresis. It should be readily understood by a person skilled in the art that the rubber compositions for pneumatic tire components including the filling or loading materials can be stirred by generally known methods in the field of rubber mixing such as mixing the various constituent rubbers vulcanizable with sulfur with various commonly used additive materials such as, for example, curing aids such as sulfur, activators, retarding agents and accelerators, processing additives such as rubber processing oils, resins including tackifying resins, silicas and plasticizers, materials filler or filler, pigments or other materials, for example, resin oil resins, zinc oxide, waxes, antioxidants and antiozonants, peptizing agents and reinforcing materials such as, for example, carbon black. As is known to those skilled in the art, depending on the intended use of the vulcanizable sulfur and vulcanized materials with sulfur (rubbers), certain of the additives mentioned above are selected and commonly used in conventional amounts. Typical carbon black additions comprise from about 20 to about 130 parts by weight per 100 parts by weight of a diene rubber (phr), although from about 30 to about a maximum of 110 phr of carbon black is desirable. for the desired high rigidity rubbers for the insert parts and indicated layers used in this invention. The amount of carbon black that is included in the most preferred insertion compound will be within the range of about 70 phr to about 90 phr. Typical resins amounts if used, including tackifying resins and stiffness resins and are used including phenol for aldehyde tackifying resins - non-reactive and also more rigid resins of reactive phenol formaldehyde resins and resorcinol or resorcinol and hexamethylene tetramine, may together comprise from about 1 to 10 phr with a resin of minimal capacity if used being of a phr and a minimum stiffening resin if it is used being 3 phr. These resins can sometimes be referred to as phenol formaldehyde type resins. Typical amounts of processing aids comprise from about 4 to about 10.0 phr. Typical amounts of silica if used comprise from about 5 to about 50 even though it is desirable from about 5 to about 15 phr and amounts of the silica coupling agent if used comprise from about 0.05 to about 0.25 parts per part of silica in weight. Representative silicas, for example, can be hydrated amorphous silicas. A representative coupling agent, for example, can be an organosilane containing bifunctional sulfur such as, for example, silica grafted with for example bis- (3-triethoxy-silylpropyl) tetrasulfide, bis- (3-trimethoxy-silylpropyl) tetrasulfide and bis - (3-trimethoxy-silylpropyl) tetrasulfide from DeGussa, AG. Typical amounts of antioxidants comprise from 1 to about 5 phr. Representative antioxidants, for example, can be diphenyl-p- - - phenylenediamine and others, such as aguels that are disclosed in The Vanderbilt Rubber Handbook (1978), pages 344-346. Suitable antiozonant (s) and waxes, particularly microcalline waxes may be of the type shown in The Vanderbilt Rubber Handbook (1978), pages 346-347. Typical amounts of antiozonants comprise from 1 to about 5 phr. Typical amounts of stearic acid and / or fatty acid of resin oil may comprise from about 1 to about 3 phr. Typical amounts of zinc oxide comprise from about 2 to about 8 or 10 phr. Typical amounts of waxes comprise from 1 to about 5 phr. Typical amounts of peptizers comprise from 0.1 to about 1 phr. The presence and relative amounts of the aforementioned additives are not an aspect of the present invention as long as the hardness and reguisites of modulus value of the filler or filler used on the sidewalls of the rim in the practice of this invention . The vulcanization of the rubber composition (s) is carried out in the presence of a sulfur vulcanization agent. Examples of sulfur vulcanization agents include elemental sulfur (free sulfur) or sulfur donor vulcanizing agents, for example, an amine disulfide, polymeric polysulfide or sulfur olefin adducts. Preferably, the sulfur vulcanization agent is elemental sulfur. As is known to those skilled in the art, the sulfur vulcanization agents are used in an amount ranging from about 0.5 to about 8 phr within the range of 2 to about 5, with the preferred amounts being for the desired rigid rubbers. for use in this invention. Accelerators are used to control the time and / or temperature that are required for vulcanization and to improve the properties of the vulcanized material. In one embodiment, a single accelerator system may be used; that is, a primary accelerator. Conventionally, a primary accelerator is used in amounts ranging from about 0.5 to about 3 phr. In another embodiment, combinations of two or more accelerators where a primary accelerator is usually used in the largest amount (from 0.5 to about 2 phr) and a secondary accelerator that is generally used in smaller quantities (from 0.5 to .50 phr) in order to activate and improve the properties of the vulcanized material. The combinations of these accelerators have historically been known to produce a synergistic effect of the final properties of rubbers cured with sulfur and are - often much better than those produced by the use of any single accelerator. In addition, delayed action accelerators can be used that are less affected by normal processing temperatures, but which produce satisfactory curing at regular vulcanization temperatures. Representative examples of accelerators include amines, disulfides, guanidines, thioureas, thiazoles, thiouramyls, sulfenamides, dithiocarbamates and xanthates. Preferably, the primary accelerator is a sulfenamide. If a second accelerator is used, the secondary accelerator is preferably a guanidine, dithiocarbamate or thiouramyl compounds, although a second sulfenamide accelerator can be used. In the practice of this invention, two or more accelerators are sometimes preferred for high rigidity rubbers. The deflated flat tire containing the inserts of this invention can be made, shaped, molded and cured by various methods that will be readily apparent to those skilled in the art. Generally, the deflated tires of this invention can be manufactured using normal techniques with of course, except for an insert that contains a material a filler or filler, - a fatty acid, a polymer of the nature of rubber that is coupled to a Group IVa metal. In a preferred embodiment, the insert of this invention is incorporated into a deflated tire of the design described in Goodyear Lawyer Number DN1998-091, filed on June 19, 1998, the teachings of which are incorporated in the present by reference in its entirety. This design relates to a flat tire of pneumatic radial layer having a running surface, a tire frame comprising a radial layer structure having at least one radial layer, a belt structure positioned between the running surface and the structure of the radial layer, two lateral sides reinforced by one or more insertion parts and a tread contour of which the laterally positioned raceway ribs are defined by circular curves having large radii of curvature. The outer layer or the single layer is reinforced with non-extensible metal cords. The lateral sides each having a rib near the radially outer region. The circular curves that define the cross-sectional contour of the central portions of the running surface and the laterally positioned tread surface intersect non-tangentially. A - The decoupling groove placed circumferentially lies below each respective non-tangential site of the points of the non-tangential intersection of the circular curves defining the cross-sectional contour of the running surface. The circular curve that defines the contour of each lateral side rib radially outwardly intersects non-tangentially the circular curve defining the contour of each laterally positioned running surface rib. A second set of decoupling grooves is positioned in such a way that in a groove it is placed circumferentially in each shoulder region where the contour defining curves intersect non-tangentially between each laterally placed side rib and the rib surface of the rib. rolling placed laterally adjacent. The most lateral decoupling grooves between the laterally disposed tread surface and the lateral side rib are circumferential and continuous or are circumferential and non-continuous. The decoupling grooves between the laterally positioned tread surface and the central portions of the tread are circumferential and straight in design or may have a zigzag pattern. In a preferred embodiment, the deflated tire is a pneumatic radial having a design of - low elongation (within the range of approximately 30 percent to approximately 60 percent). This modality has potential for deflated use in high performance sports vehicles or light trucks. The distinct feature of this deflated pneumatic rim with low elongation is that the lifting of the deflated running surface is reduced to a minimum and that the tread of the tread widens during deflated operation. In another preferred embodiment, the insert of this invention is incorporated into a deflated tire of design described in Goodyear Lawyer Number DN1998-065, filed July 6, 1998, the teachings of which are incorporated in the present by reference in its entirety. This design is related to a flat tire with a pneumatic radial layer having a running surface, a tire with two lateral sides, two radial layers extending from two heels and a belt reinforcement structure positioned radially between the surface of the tire. rolling and layers. This deflated sidewall design is characterized by an inner radial layer having metal reinforcing cords and an outer radial layer having organic fiber reinforcing cords. An insert is circumferentially positioned between the inner and outer layers in the region of each lateral side adjacent the shoulder of the running surface. The insert on each lateral side has properties characterized by high nodule and low hysteresis. The strength and rigidity of the insert can be adjusted by incorporating organic fibers that are aligned circumferentially or radially within the insert. The metal reinforcement cords in the radial and external layer have properties characterized by high modulus of elasticity, rigidity with respect to carrying the compression load in the insert pieces during deflated operation or good thermal conductivity that distributes the heat generated within the the insert pieces during the deflated operation. During deflated operation, the high modulus of the reinforcing metal cords of the outer layer carry a considerable compressive load thereby reducing the compression load carried by the single insert on each lateral side. It should also be noted that, during deflated operation, the reinforcing layer of external steel fiber has good flexibility accompanied by high stress carrying capacity. In this design it is preferred that the outer radial layer has metal cords at an angle of about 75 ° to about 105 ° - - with respect to the equatorial plane of the tire. It may also be desirable for the insert to be filled with short reinforcing fibers that are aligned circumferentially or radially to increase the tensile stress carrying capacity of the insert. It is usually preferred that these short reinforcing fibers be aligned mainly in the radial direction. In yet another preferred embodiment of this invention, the insert is incorporated into a deflated tire of the design described in US Patent Application Serial No. 08 / 865,489, filed May 29, 1997, the teachings of which are incorporated in the present by reference in its entirety. This design relates to a rim having a running surface, a belt structure and a roof frame. The cover frame has a pair of lateral sides with each lateral side having at least one layer or being reinforced with cords having a modulus of at least 10 GPa. In this rim design, at least one layer has a pair of upturned ends wound around a pair of non-extensible bead cores. Each lateral side structure has at least one insert radially inwardly of the first layer and a second layer extending at least toward each bead core. In this - - structure, the second layer is separated from the first layer by a second insert on the lateral side. At least one layer in this rim structure is reinforced with essentially non-extensible cords having a greater modulus than the modulus of the other layer. When it takes, this rim has a neutral bending axis of the side side structure closer in proximity to the reinforced layer with strings of a higher module than the reinforced layer with lower modulus strings. In a highly preferred embodiment, the first layer has synthetic cords or textiles of polyester, nylon, rayon or aramid; while the second layer, more preferably has aramid cords or metal cords; more preferably, steel ropes. The first and second insert parts preferably have a cross-sectional shape and material properties that are selected to improve the operation of inflated gait, while ensuring deflated running durability. The inserts can also be reinforced with ropes or short fibers. This invention is illustrated by the following examples which are for the purpose of illustration only and should not be construed as limiting the scope of the invention or the manner in which it may be carried out. Unless specifically indicated otherwise, the parts and percentages are given by weight.

Example 1 In this example, a coupled isoprene-butadiene rubber (IBR) that was suitable for use in the inserts of the rim of this invention was prepared in a reactor with a capacity of 3.8 liters at 70 ° C. In the method used, 2,000 grams of a sed silica / molecular sieve / aluminum premix containing 19.0 weight percent of a mixture of isoprene and 1,3-butadiene in hexanes at a ratio of 10:90 was loaded into a reactor of capacity of 3.8 liters. After the amount of impurity in the premix was determined, 4.0 milliliters of a 1.0 M solution of n-butyllithium (in hexane) was added to the reactor. The Mn of white (molecular weight averaged in number) was 100,000. The polymerization was allowed to continue at 70 ° C for three hours. An analysis of the residual monomer indicated that all monomers were consumed. Then, 1.0 milliliter of a 1 M solution of tin tetrachloride (in hexane) was added to the reactor and the coupling reaction was carried out at the same temperature for 30 minutes. During this time, 1.5 phr (parts per 100 parts by weight of rubber) of 4-t-butylcatechol and 0.5 phr of TMEDA were added to the reactor to stop the polymerization and stabilize the polymer. After the hexane solvent had evaporated, the resulting IBR was dried in a vacuum oven at 50 ° C. The coupled IBR was determined to have a glass transition temperature (Tg) at -95 ° C. It was also determined that it had a microstructure containing 7 weight percent of 1,2-polybutadiene units, 87 percent of 1,4-polybutadiene units, 1 percent of 3,4-polyisoprene units, and 9 percent of 1, 4-polyisoprene units. The Mooney viscosity (ML-4) of the processed coupled IBR was determined to be 99.

Examples 2-4 The procedure described in Example 1 was used in these Examples with the exception that the ratio of isoprene to 1,3-butadiene was changed from 10:90 to 15:85, 20.80 and 30.70. The vitreous state transition temperatures (Tgs), the Mooney viscosities (ML-4) and the icrostructures of these tin-coupled IBRs are listed in Table I. The IBR of 30/70 (Example 4) was determined to have an Mn (molecular weight averaged in - - number) of 386,000 and one Mw (molecular weight averaged by weight) of 430,000. The precursor of Example 4 (ie, the base polymer before coupling) was also determined to have an Mn of 99,000 and an Mw of 112,000.

TABLE I Ex. Composition of Tg ML-4 Microstructure (%) Isoprene / Bd ° C 1,2-PBd | 1,4-PBd | 3,4-PI I 1,4-PI 1 10/90 -95 99 7 83 2 8 2 15/85 -93 91 8 77 1 14 3 20/80 -90 82 8 72 1 19 4 30/70 -87 84 7 63 3 27 Examples 5 to 8 In these Examples, the linear IBRs were prepared in a reactor of 3,785 liters capacity. The procedure described in Example 1 was used in these examples with the exception that no coupling agent (tin tetrachloride) was used in these experiments and the target Mn was changed to 300,000 from 100,000. The ratio of isoprene to 1,3-butadiene was 10:90, - - . 85, 20:80 and 30:70. The Tg temperatures, Mooney viscosities (ML-4), Mns (molecular weights averaged in number), Mws (molecular weights averaged in weight) and microstructures of these linear IBRs are listed in Table II.

TABLE II Ex. Composition of Tg ML-4 Mn Mw Microstructure (%) Isoprene / Bd ° C 1, 2-PBd | 1, 4-PBd | 3, 4-PI | 1, 4-PI 10/90 -96 88 308K 326K 7 83 1 9 6 15/85 -94 81 307K 329K 7 77 1 15 7 20/80 -92 82 317K 338K 7 72 1 20 8 30/70 -89 87 313K 332K 6 62 2 30 Example 9 The IBR coupled with tin prepared in this experiment was synthesized in a continuous system of three reactors at 90 ° C (each of 37.85 liters). A premix containing isoprene and 1,3-butadiene in hexane was charged to a first reactor continuously at a rate of 65.6 grams per minute. The monomer solution of the premix contained - - a ratio of isoprene to 1,3-butadiene of 30:70 and had a total monomer concentration of 14 percent. Polymerization was initiated by adding 0.128 M of the n-butyl lithium solution in a first reactor at a rate of 0.4 gram per minute. The majority of the monomers were discharged at the end of the second reactor and the resulting polymerization medium containing the active materials was continuously pushed to the third reactor where the coupling agent, tin tetrachloride (0.025 M solution in hexane) was added. added at a rate of 0.34 gram per minute. The residence time for all three reactors was adjusted to 1.5 hours to achieve complete monomer conversion in the second complete coupling reactor in the third reactor. The polymerization medium was then continuously pushed to a holding tank containing the TMEDA and an antioxidant. The resulting polymer cement was then steam cleaned and the recovered IBR was dried in an oven at 60 ° C. The polymer was determined to have a vitreous state transition temperature at -85 ° C and had a Mooney viscosity ML-4 of 90. It was determined to have a microstructure containing 8 percent 1,2-polybutadiene units, 60 percent of 1,4-polybutadiene units, 29 percent of 1,4-polyisoprene units and 3 percent 3,4-polyisoprene units. The polymer was determined to have an Mn - - (molecular weight averaged in number) of 185,000 and one Mw (molecular weight averaged by weight) of 276,000. The precursor of this polymer (ie, the base polymer before the coupling) was also determined to have a Mn of 88,000 and one Mw of 151,000. Unlike Example 4 (prepared and coupled in an intermittent process), it showed symmetric coupling of four linear precursor polymers, the polymer produced in this example through a continuous process had non-symmetric coupling based on the molecular data of GPC shown in foregoing.

Examples 10 - 12 The isoprene-butadiene rubbers made in Example 4, 8 and 9 were then stirred using a normal tire tread test formulation. The tire tread test formulations were made by mixing 100 parts of the rubber that was being tested with 50 parts of carbon black, 5 parts of processing oil, 2 parts of stearic acid, 3 parts of zinc oxide, 1 part of microcrystalline wax, 0.5 part of paraffin wax, 1 part of a mixed antioxidant of aryl-p-phenylenediamine, 2 parts of N- (1, 3-dimethylbutyl) -N'-phenyl-p-phenylenediene and 1.4 parts of sulfur. The physical properties of the mixed tire tread formulations were disclosed in Table III. TABLE III Example 8 Type of Linear Rubber Coupled Coupled by continuous batch Rheometer, 150 ° C ML, dNm 1.21 1.49 1.67 MH, dNm 24.06 25.71 23.71 tsl, min 4.06 4.06 5.39 T25, min 5.62 5.78 6.50 T90, min 10.36 9.71 9.88 Autovibron, 11 Hz tan delta at 60 ° C 0.113 0.083 0.072 G "at 10 percent 2.494 2.294 2.195 G 'to l percent 3,435 2,732 2,566 Payne effect 72.6 84.4 85.5 - Examples 10-14 In this series of experiments, the active isoprene-butadiene rubber cements were continuously synthesized in a first reactor. The monomer solution of the premix had a ratio of isoprene to 1,3-butadiene of 30:70 and had a total monomer concentration of 14 percent. The polymerization was initiated by the continuous addition of n-butyllithium and carried out at a temperature of about 90 ° C. The active polymer cements and the tin tetrachloride were continuously fed into a second reactor. The second reactor provided agitation (stirring) and had an average dwell time of about 1 hour. Some of the asymmetrically tin-plated nature-bound rubber polymers in the second reactor were directly removed with a stopping material, an antioxidant and a 20 percent molar excess of TMADA (1.2 moles of TMEDA per mole of lithium butyl). ) adding to it. In some cases, the polymer cement was a polymer of the nature of the rubber asymmetrically coupled with tin and was passed through a plug flow reactor (PFR) which has a residence time of about 30 minutes before adding the antioxidant detention material and TMEDA. The polymer samples were then recovered from the polymer cements and evaluated for stability. Table IV shows the loss in Mooney viscosity ML (1 + 4) that was experienced after the samples were aged in an oven at 66 ° C for different periods of time. The molar ratio of tin tetrachloride to butyl lithium used in each of these experimental tests is also disclosed in Table IV. As an additional control, a linear isoprene-butadiene rubber that was not coupled is also evaluated. TABLE IV - _ _ Example 10 11 12 13 14 PFR Yes Yes No No No Sn / Li 0.2 0.16 - 0.3 0.24 ? Mooney - 0 day 0.0 0.0 0.0 0.0 0.0 ? Mooney - 1 day 0.1 -1.3 0.7 -0.6 - ? Mooney - 5 days 0.1 -1.4 0.8 3.6 3.9 ? Mooney - 11 days 1.2 1.55 2.8 6.7 8.6 ? Mooney - 18 days 2.4 3.1 - 10.7 10.1 ? Mooney - 22 days 3.8 3.6 - 14.1 12.2 - - As can be seen from Table IV, the asymmetrically tin-plated polymers made with the plug flow reactor (PFR) in the line had much better stability than the rubber nature samples made without using it. For example, rubber samples made with PFR on the line showed a Mooney viscosity loss ML (l + 4) after 22 days at 66 ° C of only 3.8 and 3.6, compared with losses of 14.1 and 12.2 for rubbers made without using the PFR. It should also be noted that the rubbers made with PFR in the line also showed better stability than the linear control that did not bind with tin (see Example 12). It should further be noted that TMEDA was not added to make the tin-coupled rubber sample of Example 11. This series of experiments show the insertion of PFR in a continuous line after the second reactor, but before the stop material is added, which greatly improves the stability of the processed rubber. It also shows that the inclusion of TFR in the line can eliminate the need for vision of tertiary chelation 1,2-ethylenediamine such as TMEDA to achieve satisfactory stability.

Examples 15 - 16 - - In this experiment, a tire insert composition was made using a tin-coupled polybutadiene rubber (Example 15) and compared to an identical tire insert composition., but which was made with a mixture of natural rubber and polybutadiene rubber (Example 16). In Example 16, the rubber component of the compound contained 80 phr of natural rubber and 20 phr of polybutadiene rubber. These rubber compounds were made by mechanically mixing the ingredients in a non-producing step (without curing agents) and a subsequent producing step (with curing agents). The non-producing stage, 70 phr of carbon black, 6 phr of zinc oxide, 1 phr of stearic acid, 3.5 phr of antidegradants of the diamine types of diarylpaphenylene and dihydrothrimethylquinoline, 2 phr of resin and 4 phr of the processing oil they were mixed with the rubber components for about 5 minutes at a temperature of 130 ° C in a Banbury-type mixer. Then, 2 phr of zinc oxide, 3 phr of sulfenamide / diphenyl guanidine type accelerators and about 4 phr of sulfur were mixed into the rubber compounds in a Banbury-type mixer for about 2 minutes at a temperature of about 110 °. C in the producer mixing stage. The rubber compounds are then - vulcanized at a temperature of about 150 ° C for about 20 minutes. Some of the key physical properties (processability, stiffness and hysteresis) of the cured rim insert compounds were measured on an autovibron, as shown in Table V.

TABLE V Example 15 16 Processability, G 'before healing ^ - 128 Kpa 221 KPa Rigidity, G "after curing2 3577 KPa 2644 KPa Histeresis, so d3 0.074 0.102 1 Determined at 100 ° C, 15% effort and 0.833 Hz Determined at 100 ° C, 5% effort and 11 Hz Determined at 100 ° C, 5% effort and 11 Hz As can be seen from Table V, the compound of the rim insert in this invention (Example 15) had better processability, greater stiffness exhibited less hysteresis than the rubber compound made as the control (Example 16). It is highly desirable that G 'be as low as possible before being cured for good processability. As will be seen, G "was much smaller in Example 15 where tin-coupled polybutadiene rubber was used in the rim insert part compound instead of the mixture of natural rubber and conventional polybutadiene rubber used in the control However, after curing, G 'was much higher in Example 15, which is indicative of high stiffness.It is highly desirable that the rim inserts be extremely rigid after being cured. 'should be as high as possible after the compound of the insert is cured, Therefore, the compound of the insert of the rim of this invention exhibited a lower G' before curing and also showed unexpectedly a G "much higher after curing than the rubber compound made in the control. This allows the compounds of the rim insert of this invention to be highly capable of processing and exhibiting a high level of stiffness. Although the rim insertion compositions of this invention are extremely rigid after curing, they still exhibit a low level of hysteresis. This again is a very beneficial aspect of the present invention because the low hysteresis is indicative of good rolling resistance and low - accumulation of heat in the tires. The combination of low hysteresis (low tan delta) and high stiffness is a very elusive combination of the properties that are achieved by means of the present invention.

Examples 17 - 22 In this series of experiments, some additional rim insert compounds were made using the same general procedure as that described in Examples 15-16. Examples 17 and 18 were carried out as controls. In Example 17, the rubber component of the rim insert component was a mixture of 80 phr of natural rubber and 20 phr of a conventional high cis-1,4-polybutadiene rubber. In Example 18, the rubber component of the insert compound was a polybutadiene rubber solution having 55 percent trans-microstructure, 37 percent cis-microstructure and 8 percent vinyl microstructure. The rubber component used in Example 19 was a high molecular weight tin coupled polybutadiene rubber having a Mooney viscosity ML-1 + 4 of 90. In Example 20, the rubber component of the composition of the insertion was a polybutadiene coupled with tin of - - low molecular weight which has a Mooney viscosity ML 1 + 4 of 55. The rubber component employed in Example 21 was a high molecular weight isoprene-butadiene rubber having a bonded styrene content of 30 percent and a Mooney viscosity ML 1 + 4 of 90. In Example 22, the rubber component of the insert composition was a low molecular weight isoprene-butadiene rubber having a bound 30% styrene content and a Mooney ML 1+ viscosity. 4 of 59. The key physical properties (processing capacity, stiffness and hysteresis) of the rim insert compounds cured at 50 percent, 70 percent and 90 percent carbon black (CB) loads as measured on an autovibron are shown in Table VI. As can be seen from this example, the compounds of the insert made with rubbers coupled with tin exhibited better processing capacity, greater rigidity and low hysteresis.

- TABLE VI Example 17 18 19 Rubber NR / PBD PBD HMW Sn-PBd Processing Capacity (Before Cure, G 'at 100 ° C, 15% Effort and 0.0833 Hz) 50 phr of CB 181.12 198.56 160.13 70 phr of CB 220.62 242.33 238.41 90 phr of CB 294.63 406.37 367.23 Rigidity (After Healing, G 'at 100 ° C, 5% Effort and 11 Hz 50 phr of CB 1794 2445.8 2566.5 70 phr of CB 2643.5 3176.7 3628.7 90 phr of CB 3795.3 5009.2 4971.8 Hysteresis (After Healing, Tan delta at 100 ° C, 5% Effort and 11 Hz) 50 phr of CB 0.059 0.055 0.042 70 phr of CB 0.102 0.066 0.054 90 phr of CB 0.128 0.102 0.079 - - TABLE VI (continued) Example 20 21 22 LMW Sn-PBD HM Sn-IBR LMSN-IBR Processing Capacity (Before Cure, G 'at 100 ° C, 15% Effort and 0.0833 Hz) 50 phr of CB 104.97 169.73 70 phr of CB 127.75 221.69 201.4 90 phr of CB 161.91 314.92 301.4 Rigidity (After Healing, G 'at 100 ° C, 5% Effort and 11Hz 50 phr of CB 2597.5 2113.5 70 phr of CB 2754.7 3156.4 3676.7 90 phr of CB 5376.7 4488.8 5116 Hysteresis (After Healing, Tan delta at 100 ° C, 5% Effort and 11 Hz) 50 phr of CB 0.054 0.041 70 phr of CB 0.074 0.06 0.086 90 phr of CB 0.085 0.094 0.109 - - The variations in the present invention are possible in view of the description provided herein. Although certain embodiments and representative details have been shown for the purpose of illustrating the present invention, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the scope of the present invention. Therefore, it should be understood that changes can be made in the specific embodiments described that will fall within the fully proposed scope of the invention, as defined in the following appended claims.

Claims (10)

- R E I V I N D I C A C I O N S

1. In a pneumatic tire having at least one insert to provide the pneumatic tire with deflated running capacity, the improvement characterized by using as the insert a composition of matter consisting of (1) a rubber of Cured polydiene which is coupled to a Group IVa metal selected from the group consisting of tin, lead, germanium and silicon, (2) from 20 phr to 130 phr of a filler or filler and (3) from 0.1 phr at 5 phr of a fatty acid.

2. The new tire specified in claim 1, characterized in that the filler or filler material is carbon black.

3. The nut rim specified in claim 1 or 2, characterized in that the fatty acid is a mixture of fatty acids.

4. The pneumatic tire specified in claim 1 or 2, characterized in that the carbon black is present at a level that falls within the range of 30 phr to 110"phr

5. The pneumatic tire specified in any of the claims that antecedent, characterized in that the stearic acid is present at a level that falls within the range of 0.4 phr to 3 phr

6. The pneumatic tire specified in any of the preceding claims, characterized in that the cured polydiene rubber is coupled with the tin

7. The pneumatic tire specified in any of the preceding claims, characterized in that the insert is a composition of material that also consists of 10 phr to 70 phr of natural cork

8. The pneumatic tire specified in any of the previous claims, characterized because carbon black is present at a level that is within the range of 70 phr at 90 ph

9. The tire specified in any of the preceding claims, characterized in that the stearic acid is present at a level that is within the range of 0.5 phr to 1.5 phr.

10. The pneumatic tire specified in any of the foregoing claims, characterized in that the cured polydiene rubber is a styrene-butadiene rubber. - SUMMARY OF THE INVENTION Deflated tires are usually made to include a rigid insert on the side of the tire. This insert must be as rigid as possible to help support the weight of the vehicle in which the tire is mounted in situations where there is a loss of air pressure. However, the material used to make the insert must also exhibit low hysteresis and must be capable of processing. This highly beneficial combination of properties is achieved by using the compositions of this invention to make deflated tire insert parts. This invention discloses a deflated tire consisting of a cover frame generally in toroidal shape with an outer circumferential tread band, and two separate beads, at least one layer extending from heel to heel and lateral sides extending radially from and connecting the tread with the heels; wherein the tread is adapted to contact the ground wherein the lateral sides contain at least one insert radially inward from the layer and wherein the insert consists of (1) a polydiene rubber curing that is coupled - with a Group IVa metal which is selected from the group consisting of tin, lead, germanium and silicon, (2) from about 30 phr to about 130 phr of a filler or filler and (3) from 0.1 phr to 5 phr of a fatty acid. The insert will generally extend radially inward from below the outer circumferential tread toward the heel toward which the sidewall extends. It is usually preferred that the cured polydiene rubber be coupled to the tin.