RU2395544C2 - Low-permeability thermoplastic elastomer composition - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to a thermoplastic elastomer composition which contains a nylon plasticiser and is particularly used for lining tyres and in insulating films or layers, as well as in hosepipes. The composition contains: (A) 50-80 wt % of at least one halogenated isobutylene-containing elastomer; and (B) 20-50 wt % of at least one nylon resin with melting point approximately between 170°C and 260°C; and (C) 0.5-10 wt % plasticiser which contains polyamide, with weight-average molecular weight of 20000 Da or less; where: (1) at least one of the said elastomers is present as a dispersed phase of fine vulcanised particles in the dispersion phase of the said nylon; and (2) the said elastomer particles are obtained through dynamic vulcanisation.

EFFECT: improved mixture and dispersion of rubber with retention of high level of impermeability and strength.

19 cl, 3 tbl

Description

FIELD OF THE INVENTION

The present invention relates to a thermoplastic elastomer-containing nylon plasticizer composition particularly suitable for tires and other industrial rubber applications, including hoses, and relates to a method for producing such compositions.

BACKGROUND OF THE INVENTION

The present invention relates to a thermoplastic elastomer composition particularly suitable for tires and other industrial rubber applications, including hoses, and relates to a process for the production of such compositions.

EP 0722850 B1 describes a low-permeability thermoplastic elastomer composition, which is an excellent gas-tight layer in pneumatic tires. This thermoplastic elastomer composition contains a low permeable thermoplastic matrix, such as a polyamide or a mixture of polyamides, in which dispersed low permeable rubber, such as a brominated isobutylene copolymer with parameter methyl styrene, is located. In EP 0857761 A1 and EP 0969039 A1, the relative viscosity of both the thermoplastic matrix and the dispersed rubber phase is defined as a function of the ratio of the volume of the fraction and, independently, is close to 1 in order to obtain a high concentration of fine particles of vulcanized rubber dispersed in the thermoplastic phase. In addition, EP 0969039 A1 describes that finely dispersed rubber dispersed in a thermoplastic resin matrix is necessary to achieve acceptable wear resistance, especially if it is intended to use this composition as a layer of pneumatic tires.

Compositions that exhibit low gas permeability properties (i.e., function as a gas impermeable layer) consist of a thermoplastic resin / thermoplastic resin blends such as high density polyethylene resin and nylon 6 or nylon 66 (HDPE / PA6.66) , polyethylene terephthalate and aromatic nylon (PET / MXD6), polyethylene terephthalate and a copolymer of vinyl alcohol with ethylene (PET / EVOH), where one thermoplastic resin is layered on another layer, forming multiple layers by molding, and the manufacturing process is described taxes, for example, I. Hata, Kobushi (Polymers), 40 (4), 244 (1991). In addition, the use regarding the use of such a composition as a tire layer is described in Japanese Patent Application No. 7-55929. However, since these substances are a thermoplastic resin / mixture of thermoplastic resins, despite the fact that they have excellent gas-tight properties, they are not flexible enough and, therefore, such films are subject to rupture when using a tire.

In addition, there are examples of the use of thermoplastic elastomers, which are composed of rubber and thermoplastic resin, for use as a layer or in a tire; see Japanese Patent Application No. 8-183683, but in general, the flexible material described therein having excellent wear resistance has low heat resistance. For a thermoplastic elastomer using a thermoplastic resin as a matrix having a melting point lower than the vulcanization temperature of the tire, when the vulcanized tire chamber is released at the end of the tire vulcanization cycle, the inner surface is prone to appearance defects due to adhesion or friction of the thermoplastic resin with the chamber.

Monitoring the viscosity difference between rubber and resin during the mixing process to reduce the particle size of the dispersed rubber is described by S. Wu, Polym. Eng. Sci., 27 (5), 1987. The author describes that the particle size of the dispersed rubber was reduced at a melt viscosity ratio of rubber / resin close to 1, that is, at the same viscosity. However, in EP 0 969 039 A1, it is described that when trying to obtain a thermoplastic elastomer composition having significant flexibility, strength and elongation, as well as excellent wear resistance by increasing the rubber fraction and maintaining the rubber / resin melt viscosity ratio at 1, the rubber became a matrix and the composition no longer showed thermoplasticity.

Japanese Patent Applications Nos. 8-193545, 9-175150 and 10-235386 described that in a coating structure that requires resistance to dynamic fatigue, such as a tire or sleeve, using a thermoplastic elastomer composition consisting of rubber / resin dispersed therein, in order to achieve a balance between flexibility and gas penetration preventing properties, it is useful to use a mixture of flexible N11- or N12 nylon and N6- or N66-nylon with excellent properties that inhibit oniknoveniyu gas. In addition, it was proposed to determine the volume of the fraction and the viscosity of the melt using the following equation:

where the volumes of fractions of the component of the dispersing phase and the component of the dispersing phase in the thermoplastic elastomer composition are ϕ _m and ϕ _d and the melt viscosities of the components are η _m and η _d , and in addition, the ratio of viscosities η _m and η _{d is} kept close to 1 in order to reduce particle size dispersed rubber domain for increased wear resistance. However, in EP 0 969 039 A1, it is described that at low temperature only a reduction in the particle size of the rubber leads to unsatisfactory wear resistance.

The present invention addresses the limitations of previous approaches in order to improve performance. Namely, the present composition, containing fine particles of a rubber domain dispersed in a thermoplastic matrix exhibiting improved gas or vapor impermeability properties and good strength and wear resistance, is suitable for use in tires and sleeves.

Other references of interest include: WO 2004/081107, WO 2004/081106, WO 2004/081108, WO 2004/081116, WO 2004/081099, GB 2163971, US 5275906, US 6367381, WO 96/25453, US 6399704, US 6395811 , US 6,617,383, JP-2003-026931, US-2003-0022993, US 5105544, US 5938869, US 6359071, and US 6397912.

SUMMARY OF THE INVENTION

The present invention relates to a thermoplastic elastomer composition comprising (A) at least one halogenated isobutylene-containing elastomer; and (B) at least one nylon resin having a melting point of from about 170 ° C to about 260 ° C; and (C) a polyamide plasticizer; where: (1) at least one of the specified halogenated isobutylene-containing elastomer is present as the dispersing phase of the fine vulcanized particles in the dispersion phase of the specified nylon; and (2) said halogenated isobutylene-containing elastomeric particles were obtained by dynamic vulcanization.

In an alternative embodiment, the invention also relates to a thermoplastic elastomer composition comprising (A) at least one halogenated isobutylene-containing elastomer; and (B) at least one nylon resin having a melting point of from about 170 ° C to about 260 ° C and having a complex viscosity; and (C) a plasticizer suitable for reducing the complex viscosity of said at least one nylon resin while substantially maintaining the level of oxygen permeability available for a substantially similar composition in the substantially complete absence of said plasticizer; where: (1) at least one specified halogenated isobutylene-containing elastomer is present as the dispersed phase of the fine vulcanized particles in the dispersed phase of the specified nylon; and (2) said halogenated isobutylene-containing elastomer particles were obtained by dynamic vulcanization.

In another alternative embodiment, the invention also relates to a thermoplastic elastomer composition, mainly consisting of a dynamically vulcanized mixture: (A) about 55 weight percent brominated isobutylene-p-methylstyrene elastomer; and (B) about 40 weight percent nylon copolymer resin 6/66; (C) about 4 weight% plasticizer, mainly consisting of a nylon resin having a viscosity at 200 ° C of about 4 Pa · s, where the specified elastomer is present as the dispersed phase of the small dynamically vulcanized particles in the dispersion phase of the specified nylon and where the specified dynamic vulcanization held in a twin screw extruder.

Detailed description

Preferred applications of the present invention relate to thermoplastic elastomer compositions for tire interlayers and backing layers, more specifically, thermoplastic elastomer compositions exhibiting excellent strength and impermeability to fluids such as air or liquids. Preferred compositional characteristics relate to the desired content of dispersed halogenated isobutylene-containing elastomers in the form of vulcanized particles dispersed in a polyamide thermoplastic matrix, where such a dispersed system has been successfully obtained using a suitable plasticizer that facilitates the mixing and processing of rubber and polyamide components. In addition, particularly preferred aspects of the invention relate to a method for producing a plasticized thermoplastic elastomer composition capable of providing a rubber domain containing fine particles, these domains being also highly stretchable and elastic, where the composition has an oxygen impermeability level that is comparable to a composition that is completely absent such a plasticizer. Moreover, the invention includes a process for producing pneumatic tires and hoses using the above compositions.

Preferred elastomers suitable in the composition of the present invention have low permeability and are preferably halogenated isobutylene-containing elastomers, and particularly preferably are brominated isobutylene-containing elastomers, extremely preferably brominated copolymers of parameter styrene and isobutylene; bromobutyl elastomers having a high content of the structure shown below are also preferred; and also preferred are commercial bromobutyl elastomers or mixtures thereof with one or more of the above brominated elastomers with one another or with other polymers.

The new numbering scheme used here for the Periodic Table Groups was used as described in CHEMICAL AND ENGENEERING NEWS, 63 (5), 27 (1985). All molecular weights are average weights unless otherwise indicated.

Everywhere in the description, including the claims, the word “comprise” and variations of the word such as “comprising” as well as “have”, “having”, “include” and “including” and their variations mean that the named stages, elements or the substances to which this applies are basic, however other stages, elements and substances can be added and will continue to form a construct as part of the claims or descriptions. If the listing occurs in the description of the invention and in the claims, it means that the invention and the claims consider what follows, and possibly more. This term, especially if used in the claims, is encompassing or not limited to and does not exclude additions, non-listed elements or methods of the step.

In this context, “consisting entirely of” means the exclusion of any element or combination of elements, as well as any number of another element or combination of elements that could change the main and new features of the invention. Thus, by way of example only, a thermoplastic composition obtained using a method other than that involving dynamic vulcanization should be excluded. Otherwise, and again just by way of example, a plasticized thermoplastic composition in which a plasticizer leads to the formation of a composition having significantly greater oxygen permeability than that suitable for a composition intended for use as a layer of tires should be excluded.

For the purposes of the present invention, unless otherwise indicated in relation to a particular property, characteristic or variable, the term “mainly”, when applied to any criterion, such as a property, characteristic or variable, means achieving the specified criterion in such an amount that the specialist in the field of technology, he must understand that in order to achieve an advantage, or a condition, or a valuable property, the necessary is achieved. The term "mainly" also expediently serves to describe the subject matter of the invention so that it will be understood by a person skilled in the art, and in order to distinguish the claimed subject matter from the prior art.

The polymer can be used to determine homopolymers, copolymers, interpolymers, terpolymers, etc. Similarly, a copolymer may refer to a polymer containing at least two monomers, possibly with other monomers.

If the polymer is called containing monomer, then the monomer is present in the polymer in the polymerized form of the monomer or derivative form of the monomer. However, for simplicity, the standard phrase “containing (corresponding) monomer” or the like is used as an abbreviation. Similarly, when the components of the catalyst are described as containing neutral stable forms of the components, it is clear to one skilled in the art that the active form of the component is that which reacts with monomers to produce polymers.

Isoolefins refer to any olefin monomers having two substituents on one carbon atom.

Polyolefins refer to any monomer having two or more double bonds. In a preferred embodiment, the polyolefin is a monomer containing two double bonds, preferably two conjugated double bonds, for example a conjugated diene, such as isoprene.

The elastomer or elastomers used in the present description, refers to any polymer or polymer composition corresponding to ASTM D1566 definition. The term may be used interchangeably with the term “rubber (s)”.

Alkyl refers to a paraffinic hydrocarbon group that can be obtained from alkane by removing one or more hydrogens from a formula, such as, for example, a methyl group (CH ₃ ) or an ethyl group (CH ₃ CH ₂ ), etc.

Aryl refers to a hydrocarbon group forming a ring system characteristic of aromatic compounds, such as, for example, benzene, naphthalene, phenanthrene, anthracene, etc., and usually has alternating double bonds (“unsaturation”) in the structure. An aryl group is such a group derived from an aromatic compound by removing one or more hydrogens from a formula, such as, for example, phenyl or C ₆ H ₅ .

Substituted means that at least one hydrogen is substituted with at least one substituent selected from, for example, halogen (chlorine, bromine, fluorine or iodine), amino, nitro, sulfoxy (sulfonate or alkyl sulfonate), thiol, alkylthiol and hydroxyl; straight or branched chain alkyl having from 1 to 20 carbon atoms, including methyl, ethyl, propyl, tert-butyl, isopropyl, isobutyl, etc .; alkoxy, linear or branched alkoxide having from 1 to 20 carbon atoms and including, for example, methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, sec-butoxy, tert-butoxy, pentyloxy, isopentyloxy, hexyloxy, heptyloxy, octyloxy, nonyloxy and decyloxy; haloalkyl having a linear or branched alkyl chain having from 1 to 20 carbon atoms, which contains at least one halogen, and includes, for example, chloromethyl, bromomethyl, fluoromethyl, iodomethyl, 2-chloroethyl, 2-bromoethyl, 2- fluoroethyl, 3-chloropropyl, 3-bromopropyl, 3-fluoropropyl, 4-chlorobutyl, 4-fluorobutyl, dichloromethyl, dibromomethyl, difluoromethyl, diiodomethyl, 2,2-dichloromethyl, 2,2-dibromomethyl, 2,2-difluoromethyl, 3, 3-dichloropropyl, 3,3-difluoropropyl, 4,4-dichlorobutyl, 4,4-difluorobutyl, trichloromethyl, 4,4-difluorobutyl, trichloromethyl, trifluoromethyl, 2,2,2-trifluoroethyl, 2,3,3-trifluoropropyl, 1,1,2,2-tetrafluoroethyl and 2,2,3,3-tetrafluoropropyl. Thus, for example, a “substituted styrene moiety” includes p-methylstyrene, p-ethylstyrene, etc.

The present invention contains at least one halogenated isobutylene-containing elastomer. Typically, it is present in the composition together with the described thermoplastic technical resin in a ratio by weight of rubber to resin of from about 50/50 to 80/20; preferably from about 55/45 to about 75/25; more preferably from about 60/40 to about 75/25. A halogenated isobutyl-containing elastomer is defined as an elastomer having at least about 0.1 mol% of halogen, which halogen is selected from the group consisting of bromine, chlorine and iodine, preferably bromine or chlorine. Preferably, halogenated isobutylene-containing elastomers suitable in the present invention include halogenated isobutylene-containing homopolymers or copolymers. These polymers can be described as a disordered polymer derived from a C ₄ to C ₇ isomonoolefin block, such as an isobutylene block and at least one other polymerizable block. In one embodiment, the isobutylene-based halogenated copolymer is butyl rubber or branched butyl rubber, in particular a brominated version of these elastomers. (Suitable unsaturated butyl rubbers such as homopolymers and copolymers of olefins or isoolefins and other types of elastomers suitable for the invention are well known and described in RUBBER TECHNOLOGY 209-581 (Maurice Morton ed., Chapman & Hall 1995), THE VANDERBILT RUBBER HANDBOOK 105 -122 (Robert F. Ohm ed., RT Vanderbilt Co., Inc 1990), and Edward Kresge and HC Wang in KIRK-OTHMER ENCYCLOPEDIA OD CHEMICAL TECHNOLOGY 934-955 (John Wiley & Sons, Inc. 4th ed. 1993)) . Preferred halogenated isobutylene-based homopolymers or copolymers useful in the present invention include halogen butyl rubbers such as bromobutyl rubber and chlorobutyl rubber.

Butyl rubbers are usually prepared by reacting a mixture of monomers having at least (1) a C ₄ to C ₁₂ isoolefin monomer component, such as isobutylene, with a (2) polyolefin monomer component. In one embodiment, the isoolefin is present in the range of from 70 to 99.5% by weight, based on the weight of the total mixture of monomers, and in another embodiment, from 85 to 99.5%. In one embodiment, the polyolefin component is present in the mixture of monomers from 30 to 0.5 weight%, and in another embodiment, from 15 to 0.5 weight%. In yet another embodiment, from 8 to 0.5 weight% of the monomer mixture is a polyolefin. Preferably, the isoolefin is a compound from C ₄ to C ₁₂ , non-limiting examples of which are compounds such as isobutylene, isobutene, 2-methyl-1-butene, 3-methyl-1-butene, 2-methyl-2-butene, 1 butene, 2-butene, methyl vinyl ether, indene, vinyltrimethylsilane, hexane and 4-methyl-1-pentene. A polyolefin is a C ₄ to C ₁₄ polyolefin, for example, such as isoprene, butadiene, 2,3-dimethyl-1,3-butadiene, myrcene, 6,6-dimethyl fulvene, hexadiene, cyclopentadiene, and piperylene, and other monomers which described in EP 0279456 and US patents Nos. 5506316 and 5162425. Other polymerizable monomers such as styrene and dichlorostyrene are also suitable for homopolymerization and copolymerization in butyl rubbers. In one embodiment, a butyl rubber polymer suitable for the invention is formed by the reaction of from 95 to 99.5 weight% of isobutylene with from 0.5 to 8 weight% of isoprene, or in another embodiment, from 0.5 weight% to 5.0 weight% isoprene. Butyl rubbers and methods for their preparation are described in detail, for example, in US patent No. 2356128, 3968076, 4474924, 4068051 and 5532312.

Halogenated butyl rubbers are formed by halogenating the butyl rubber product described above. Halogenation can be carried out by any means, and the present invention is not limited to the halogenation process. Methods for halogenating polymers such as butyl polymers are described in US 2631984, 3099644, 4288575, 4554326, 4632963, 4681921, 4650831, 4384072, 4513116 and 5681901. In one embodiment, the butyl rubber is halogenated in a hexane solvent at 4 to 60 ° C. bromine (Br ₂ ) or chorus (Cl ₂ ) as a halogenating agent. Subsequent treatment of the halogenated butyl rubber as described in US Pat. No. 4,288,575 may also be used. Usually, the halogenated rubber has a Mooney viscosity of about 20 to about 70 (ML 1 + 8 at 125 ° C); in another embodiment, for example, from about 25 to about 55. The halogen content is usually from about 0.1 to 10% by weight, based on the weight of the halogenated butyl rubber; for example, from about 0.5 to 5 weight%; alternatively, from about 0.8 to about 2.5 weight%; for example, from about 1 to about 2 weight%. A particularly preferred form of halogenated butyl rubber contains a high content of the following halogenated structure (preferably 60 to 95% according to NMR), where X is halogen and, in a particularly preferred embodiment, halogen is bromine; otherwise, the halogen is chlorine:

A commercial embodiment of the halogenated butyl rubber useful in the present invention is Bromobutyl 2222 (ExxonMobil Chemical Company). Typically, its Mooney viscosity is from about 27 to 37 (ML 1 + 8 at 125 ° C, ASTM 1646, modified), and its bromine content is from about 1.8 to 2.2 weight% relative to Bromobutyl 2222. In addition, The vulcanization characteristics of Bromobutyl 2222 that are provided by the manufacturer are as follows: MN from about 28 to 40 dN m, ML from about 7 to 18 dN m (ASTM D2084). Another commercial embodiment of the halogenated butyl rubber useful in the present invention is Bromobutyl 2255 (ExxonMobil Chemical Company). Its Mooney viscosity is from about 41 to 51 (ML 1 + 8 at 125 ° C, ASTM 1646), and its bromine content is from about 1.8 to 2.2 weight%. In addition, the vulcanization characteristics provided by the manufacturer are as follows: MN from about 34 to 48 dN m, ML from about 11 to 21 dN m (ASTM D2084). Commercial isobutylene polymers are described in detail by R.N. Webb, T.D. Shaffer and A.H. Tsou, “Commercial Isobutylene Polymers,” Encyclopedia of Polymer Science and Technology, 2002, John Wiley & Sons, incorporated herein by reference.

Another suitable variant of halogenated butyl rubber is halogenated, branched or star-branched butyl rubber. These rubbers are described, for example, in EP 0678529 B1, US 5182333 and 5071913, each included in this description by reference. In one embodiment, a star-branched butyl rubber (“SBB”) is a composition comprising butyl rubber and a polydiene or block copolymer. For the purposes of the present invention, the method for producing SBB is not a limitation. Polydienes, block copolymers or branching agents (hereinafter “polydienes") are usually cationic and are present in the polymerization of butyl or halogenated butyl rubber, or may be mixed with butyl rubber to form SBB. The branching agent or polydiene may be any suitable branching agent, and the invention is not limited to the polydiene or branching agent that is used to create the SBB.

In one embodiment, SBB is a composition of butyl or halogenated butyl rubber as described above and a copolymer of polydiene and partially hydrogenated polydiene selected from the group consisting of styrene, polybutadiene, polyisoprene, polypiperylene, natural rubber, styrene-butadiene rubber, ethylene-rubber, ethylene-butadiene rubber, ethylene (EPDM), ethylene-propylene rubber (EPM), styrene-butadiene-styrene and styrene-isoprene-styrene block copolymers. Polydienes may be present in an amount, based on the total monomer content in weight%, usually in excess of 0.3 weight%; alternatively, from about 0.3 to about 3 weight%; or from about 0.4 to 2.7 weight%.

Preferably, the branched or star-branched butyl rubber used in this specification is halogenated. In one embodiment, the halogenated star-branched butyl rubber (“HSBB”) comprises halogenated or non-halogenated butyl rubber and a halogenated or non-halogenated polydiene or block copolymer. The halogenation process is described in detail in US 4074035, 5071913, 5286804, 5182333 and 6228978. The present invention is not limited to methods for producing HSBB.

The polydiene / block copolymer or branching agents (hereinafter “polydienes") are usually cationic and are present during the polymerization of butyl or halogenated butyl rubber, or may be mixed with butyl rubber to form HSBB. The branching agent or polydiene may be any suitable branching agent, and the invention is not limited to the type of polydiene that is used to create the HSBB.

In one embodiment, usually the HSBB is a composition comprising halogenated butyl rubber as described above and a copolymer of polydiene and partially hydrogenated polydiene selected from the group consisting of styrene, polybutadiene, polyisoprene, polypiperylene, natural rubber, styrene-butadiene rubber, these rubber, styrene-butadiene-styrene and styrene-isoprene-styrene block copolymers. Polydienes may be present in an amount, based on the total monomer content in weight%, usually in excess of 0.3 weight%; alternatively, from about 0.3 to about 3 weight%; or from about 0.4 to 2.7 weight%.

A commercial embodiment of the HSBB useful in the present invention is Bromobutyl 6222 (ExxonMobil Chemical Company) having a Mooney viscosity (ML 1 + 8 at 125 ° C, ASTM 1646) from about 27 to 37, and the bromine content therein is from about 2 , 2 to 2.6 weight%. In addition, the vulcanization characteristics of Bromobutyl 6222, which are provided by the manufacturer, are as follows: MN from 24 to 38 dN m, ML from 6 to 16 dN m (ASTM D2084).

Preferred isoolefin / para-alkyl styrene copolymers include random copolymers containing from C ₄ to C ₇ isoolefin, such as isobutylene and halogenmethyl styrene. Halogenmethylstyrene may be ortho-, meta- or paraalkyl substituted with styrene. In one embodiment, halogenmethylstyrene is p-halogenomethylstyrene containing at least 80%, more preferably at least 90% by weight of the paraisomer. The halogen group may be any halogen, preferably chlorine or bromine. The copolymer may also include functionalized copolymers in which at least several groups of alkyl substituents present in the styrene monomer blocks contain benzyl halogen or another functional group, which is described below. These copolymers are referred to herein as “isoolefin copolymers containing halogenmethyl styrene” or simply “isoolefin copolymers”.

Preferred isoolefin copolymers may include monomers selected from the group consisting of isobutylene or isobutene, 2-methyl-1-butene, 3-methyl-1-butene, 2-methyl-2-butene, 1-butene, 2-butene, methyl vinyl ether, indene, vinyltrimethylsilane, hexane and 4-methyl-1-pentene. Preferred isoolefin copolymers may also contain polyolefins, preferably C ₄ to C ₁₄ polyolefins, such as isoprene, butadiene, 2,3-dimethyl-1,3-butadiene, myrcene, 6,6-dimethyl-fulvene, hexadiene, cyclopentadiene, and piperylene, and other monomers that are described in EP 279456 and US 5,506,316 and 5,162,425. Preferred styrene monomers in the isoolefin copolymer include styrene, methyl styrene, chlorostyrene, methoxystyrene, indene and indene derivatives, and combinations thereof.

Preferred isoolefin copolymers can be described as copolymers containing the following monomer units that are randomly arranged in a polymer chain:

where R and R ¹ independently are halogen, lower alkyl, preferably C ₁ to C ₇ alkyl, and primary or secondary alkyl halide, and X is a functional group such as halogen. Preferably, the halogen is chlorine, bromine, or a combination thereof. Preferably, R and R ¹ are each hydrogen. The —CRR ₁ H and —CRR ₁ X groups may be substituents on the styrene ring in the ortho, meta, or para positions, preferably in the para position. In one embodiment, up to 60 mol% of the p-substituted styrene present in the copolymer structure may be the above functionalized structure (2), in another embodiment, from 0.1 to 5 mol%. In yet another embodiment, the amount of functionalized structure (2) is in the range from 0.4 to 1 mol%. Functional group X may be halogen or some other functional group that may be incorporated by nucleophilic substitution of benzyl halogen by other groups, such as carboxylic acids; carboxylic acid salts; esters, amides and imides; hydroxy; alkoxides; phenoxides; thiolates; thioethers; xanthates; cyanides; cyanates; amines and mixtures thereof. These functionalized isoolefin copolymers, methods for their preparation, methods of functionalization and vulcanization are described in more detail in US 5162445.

The most suitable of these copolymers of isobutylene and p-methyl styrene are those containing from 0.5 to 20 mol% of p-methyl styrene, where up to 60 mol% of the methyl substituted groups present in the benzene ring contain a bromine or chlorine atom, preferably a bromine atom (p-bromomethyl styrene ), as well as their acidic or ester functionalized version, where the halogen atom is replaced by maleic anhydride, or acrylic, or methacrylic functional group. These copolymers are called "halogenated isobutylene-p-methylstyrene copolymers" or brominated isobutylene-p-methylstyrene copolymers "and are commercially available under the name EXXPRO ^™ Elastomers (ExxonMobil Chemical Company, Houtson TX). It should be understood that the use of the terms “halogenated” or “brominated” does not limit the halogenation methods of the copolymer, but merely describes a copolymer that contains isobutylene derivatives, p-methylstyrene derivatives and p-halogenomethylstyrene derivatives.

Preferably, these functionalized polymers have a substantially homogeneous compositional distribution so that at least 95% by weight of the polymer has a p-alkyl styrene content of 10% of the average polymer p-acyl styrene content (as defined and described in US 5162445). More preferred polymers also have a narrow molecular weight distribution (Mw / Mn) of less than 5, more preferably less than 2.5, a preferred average viscosity molecular weight is in the range of about 200,000 to about 2,000,000, and a preferred number average molecular weight is in the range of about 25,000 to about 750,000, as determined by gel permeation chromatography.

Preferably, the halogenated copolymers of isobutylene and p-methylstyrene are brominated polymers, which mainly contain from about 0.1 to about 5 weight% bromomethyl groups. In another embodiment, the amount of bromomethyl groups is from about 0.2 to about 2.5 weight%. According to another approach, preferred copolymers contain from about 0.05 to about 2.5 mol% of bromine, based on the weight of the polymer, more preferably from about 0.1 to about 1.25 mol% of bromine, and generally do not contain halogen in the ring, or halogen in the polymer backbone. In one embodiment, the copolymer is a copolymer of C ₄ to C ₇ units, derived units of isomonoolefin, derivatives of p-methylstyrene and units derived from p-halogenmethyl styrene, where p-halogenmethyl styrene units are present in the copolymer from about 0.4 to about 1 molar %, based on the copolymer. In another embodiment, p-halogenmethylstyrene is p-bromomethylstyrene. Mooney viscosity (1 + 8, 125 ° C, ASTM 1646, modified) is in the range from about 30 to about 60 Mooney units.

In another embodiment, the ratio between the ternary fraction of isoolefin and p-alkyl styrene and the molar% of p-alkyl styrene included in the copolymer is described by the copolymer sequence distribution equation below and is determined by the copolymer sequence distribution parameter m.

F = 1- {m A / (1 + mA)},

where: m is a copolymer sequence distribution parameter,

A is the molar ratio of p-alkylstyrene to isoolefin in the copolymer and,

F is the p-alkylstyrene-isoolefin-p-alkylstyrene triple fraction in the copolymer.

The best fit for this equation is given by m for the copolymerization of the isoolefin and p-alkylstyrene in a particular solvent. In some embodiments, m is less than 38; alternatively less than 36; alternatively less than 35; and alternatively, less than 30. In other embodiments, m is 1-38; alternatively 1-36; alternatively 1-35; and alternatively 1-30. WO2004058825 and WO2004058835 describe copolymers having such characteristics.

In another embodiment, the isoolefin / para-alkyl styrene copolymer is substantially free of long, branched chains. For the purposes of the present invention, a polymer that basically does not contain long branched chains is defined as a polymer for which g` _vis.avg. set to or equal to 0.978, alternatively equal to or equal to 0.980, alternatively equal to or equal to 0.985, alternatively equal to or equal to 0.990, alternatively equal to or equal to 0.995, alternatively equal to or equal to 0.998, alternatively equal to or equal to 0.999, as defined using triple detection exclusion chromatography (SEC), as described below. Such polymers are also described in WO2004058825 and WO2004058835.

In another embodiment, the ratio between the ternary fraction of the isoolefin and the polyolefin and the molar% of the polyolefin included in the halogenated rubber copolymer is described by the copolymer sequence distribution equation below and is determined by the copolymer sequence distribution parameter m.

F = mA / (1 + mA) ² ,

where: m is a copolymer sequence distribution parameter,

A is the molar ratio of polyolefin to isoolefin in the copolymer and,

F is an isoolefin-polyolefin-polyolefin triple fraction in the copolymer.

The following describes the measurement of the triple fraction of the isoolefin and the polyolefin and the molar% of the polyolefin included in the copolymer. The best fit for this equation is given by m for the copolymerization of the isoolefin and polyolefin in any solvent. In some embodiments, m is greater than 1.5; alternatively, greater than 2.0; alternatively, greater than 2.5; alternatively, greater than 3.0; and alternatively, greater than 3.5. In other embodiments, m is in the range of 1.10 to 1.25; alternatively, from 1.15 to 1.20; alternatively, 1.15 to 1.25; and alternatively, m is about 1.20. Halogenated rubbers that have such characteristics are described in WO 2004058825 and WO 2004058835.

In another embodiment, halogenated rubber generally does not contain long, branched chains. For the purposes of the present invention, a polymer that basically does not contain long branched chains is defined as a polymer for which g` <sub>vis.avg.</sub> set to or equal to 0.978, alternatively equal to or equal to 0.980, alternatively equal to or equal to 0.985, alternatively equal to or equal to 0.990, alternatively equal to or equal to 0.995, alternatively equal to or equal to 0.998, alternatively equal to or equal to 0.999, as defined using size exclusion chromatography with triple detection, as described below. The presence or absence of long chain branching in polymers is determined using triple detection size exclusion chromatography. Triple-size exclusion chromatography was performed on a Waters (Milford, Massachusetts) 150C chromatograph, operating at 40 ° C, equipped with precision detectors (Bellingham, Massachusetts), PD2040 light scattering detector, Viscotek (Hutson, Texas) model 150R, viscosity-index differential detection detector Waters (together with 150C). The detectors are connected in series, the light scattering detector being the first, the viscosity detector second and the differential refractive index detector third. Tetrahydrofuran (0.5 ml / min) with a set of three Polymer Laboratories, LTD. Was used as an eluent. (Shropshire, United Kingdom) 10 micron mixed-B / LS GPC columns. The equipment is calibrated against 16 narrow polystyrene standards (Polymer Laboratories, Ltd.). Data was obtained using TriSEC software (Viscotek) and imported into WaveMetric`s Igor Pro program (Lake Oswego, OR) for analysis. To establish the relationship between the intrinsic viscosity [η] _linear determined using a viscosity detector and molecular weight (M _w determined using a light scattering detector), linear polyisobutylene was used. The relationship between [η] _linear and M _{w is} expressed by the Mark-Houwink equation.

[η] _linear = KM _w ^α

The parameter K and α are obtained from the double logarithmic diagram of the internal viscosity M _w , α is the slope, K is the intersection point. Significant deviations from the behavior obtained for linear standards show the presence of long, branched chains. Basically, samples that exhibit large deviations from linear behavior contain more pronounced long branched chains. Coefficient g` also shows deviations from a certain linear behavior.

[η] _sample = g` [η] _linear

A certain value of g` may be less than or equal to unity and greater than or equal to zero. If g` is equal to or close to unity, then the polymer is considered to be linear. If g` is much less than unity, then the sample has long branched chains. For example, see EF Casassa and GC Berry in “Comprehensive Polymer Science,” Vol. 2, (71-120) G. Allen and JC Bevington, Ed., Pergamon Press, New York, 1988. In triple detection size exclusion chromatography, g` is calculated for each piece of data of the chromatographic curve. Medium viscosities g` or g` _vis.avg. calculated by molecular weight distribution. Coefficient g` _vis.avg. calculated from the average intrinsic viscosity of the sample:

g` _vis.avg. = [η] avg ./ (KM _W ^α )

Other preferred halogenated elastomers or rubbers include halogenated isobutylene-p-methylstyrene-isoprene copolymers as described in WO 01 / 21672A1. Halogenated rubbers suitable in fluid barrier layers may be similar or different.

For the purposes of the present invention, a technical resin (also called “technical thermoplastic resin”, “thermoplastic resin” or “thermoplastic technical resin”) is defined as any thermoplastic polymer, copolymer or mixture thereof having a Young's modulus of elasticity of more than 500 MPa and preferably a melting point of from about 170 ° C to about 260 ° C, more preferably less than 260 ° C, most preferably less than 240 ° C, and a molecular weight of more than about 20,000 daltons, preferably more than about 50,000 dal tone, including, but not limited to, one or more of the following:

a) polyamide resins: nylon 6 (No. 6), nylon 66 (No. 66), nylon 46 (No. 46), nylon 11 (No. 11), nylon 12 (No. 12), nylon 610 (No. 610), nylon 612 ( No. 612), nylon 6/66 copolymer (No. 6/66), nylon 6/66/610 (No. 6/66/610), nylon MXD6 (No. MXD6), nylon 6T (No. 6T), nylon 6 / 6T copolymer (No. 6), nylon 66 / PP copolymer, nylon 66 / PPS copolymer;

b) polyester resins: polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polyethylene isophthalate (PEI), PET / PEI copolymer, polyacrylate (PAR), polybutylene naphthalate (PBN), liquid crystalline polyester, polyoxyalkylate di-polyethylene diimide other aromatic polyesters;

c) polynitrile resins: polyacrylonitrile (PAN), polymethacrylonitrile, copolymers of acrylonitrile and styrene (AS), copolymers of methacrylonitrile and styrene, methacrylonitrile-styrene-butadiene copolymers;

d) polymethacrylate resins: polymethacrylate, polymethyl methacrylate;

e) polyvinyl resins (for illustration, without limitation): vinyl acetate (EVA), polyvinyl alcohol (PVA), vinyl alcohol-ethylene copolymer (EVOA), polyvinylidene chloride (PVDC), polyvinyl chloride (PVC), polyvinyl chloride and polyvinylidene copolymer, polyvinylidene copolymer methacrylate;

f) cellulose resins: cellulose acetate, cellulose acetate butyrate;

g) fluorine-containing resins: polyvinylidene fluoride (PVDF), polyvinyl fluoride (PVF), polychlorofluoroethylene (PCTFE), tetrafluoroethylene-ethylene copolymer (ETFE);

h) polyamide resins: aromatic polyamides;

i) polysulfones;

j) polyacetals;

k) polyactones;

l) polyphenylene oxides and polyphenylene sulfides;

m) styrene maleic anhydride;

n) aromatic polyketones; and

o) a mixture of any and all from a) to n), including also mixtures of any illustrative or used as an example, technical resins with each of a) to n).

For the purposes of the present invention, this definition of technical resin excludes polymers of olefins, such as polyethylene or polypropylene.

Preferred technical resins include polyamide resins and mixtures thereof; particularly preferred resins include nylon 6, nylon 6/66 copolymer, nylon 11, nylon 12, nylon 610, nylon 612, and mixtures thereof. According to an alternative preferred embodiment of the present invention, a thermoplastic elastomer composition can be prepared using a thermoplastic resin component, wherein the nylon resin component comprises nylon 11 or nylon 12 and nylon 6/66 copolymer in the composition in a ratio (ratio by weight) of from about 10 / 90 to about 90/10; preferably from about 30/70 to about 85/15. Such a resin mixture thermoplastic elastomer composition can provide a thermoplastic elastomer composition having excellent wear resistance and appearance, for example, of a vulcanized surface of a tire interlayer, as well as excellent air retention properties and a good balance of these properties.

Optionally, other rubbers or elastomers may be used in combination with a halogenated isobutylene-containing elastomer. Such an optional rubber component includes high diene rubbers and their hydrates. High diene rubbers or elastomers also refer to high diene monomer rubbers. This is usually rubber containing at least 50 mol% of a C ₄ -C ₁₂ diene monomer, usually at least from about 60 mol% to about 100 mol%; more preferably not less than from about 70 mol% to about 100 mol%; more preferably at least from about 80 mol% to about 100 mol%. Suitable rubbers with a high content of diene monomer include homopolymers and copolymers of olefins, or isoolefins, and polyolefins, or homopolymers of polyolefins. They are well known and described in RUBBER TECHNOLOGY, 179-374 (Maurice Morton ed., Chapman & Hall 1995), and THE VANDERBILT RUBBER HANDBOOK 22-80 (Robert F. Ohm ed., RT Vanderbilt Co., Inc. 1990). Generally, other optional rubbers useful in the present invention include, for example, natural rubber (NR), isoprene rubber (IR), epoxidized natural rubber, styrene-butadiene rubber (SBR), polybutadiene rubber (BR) (including higher cis BR and lower cis BR), nitrile butadiene rubber (NBR), hydrogenated NBR, hydrogenated SBR, olefin rubbers (e.g. ethylene propylene rubbers, including both EPDM and EPM), maleic acid modified ethylene propylene rubbers (M-EPM), butyl rubber (IIR) copolymers of isobutylene and aromatic vinyl or diene monomer, acrylic rubbers (ACM), ionomers, other halogen-containing rubbers (e.g. chloroprene rubbers (CR), hydrin rubbers (CHR), chlorosulfonium polyethylenes (CSM), chlorinated polyethylenes (CM), chlorinated maleic acid modified polyethylenes) (M-CM)), silicone rubbers (e.g. methyl vinyl silicone rubbers, dimethyl silicone rubbers, methyl phenyl vinyl silicone rubbers), sulfur-containing rubbers (e.g. polysulfide rubbers), fluorinated rubbers (e.g. vinylidene fluoride rubbers, rubbers based on the fluorine-containing vinyl ether, tetrafluoroethylene-propylene rubbers, fluorine-containing silicone rubbers, fluorine-containing fosfagenovye rubbers), thermoplastic elastomers (e.g., styrene-containing elastomers, olefin elastomers, ester elastomers, urethane elastomers, or polyamide elatstomery), and mixtures thereof.

Preferred examples of high diene monomer rubbers include polyisoprene, polybutadiene rubber, styrene butadiene rubber, natural rubber, chloroprene rubber, acrylonitrile butadiene rubber, and the like, which can be used alone or in combination and blends.

Since thermoplastic technical resins and halogenated isobutylene-containing rubbers differ significantly in solubility, an optional compatibilizing agent may also be useful to increase the mixing of these polymers. Such compatibilizing agents include ethylenically unsaturated nitrile-conjugated highly saturated diene copolymer rubbers (HNBR), epoxidized natural rubbers (ENR), NBR, hydrin rubbers, acrylic rubbers and mixtures thereof. Compatibility enhancing agents are believed to act by altering, in particular decreasing, the surface tension between rubber and resin components. Other compatibilizing agents include copolymers having the structure of either one of the thermoplastic resins and polymer rubber, or the structure of a copolymer having an epoxy group, a carbonyl group, a halogen group, an amino group, a maleic group, an oxazole group, a hydroxyl group, and the like. . capable of reacting with a thermoplastic resin or polymer rubber. They can be selected based on the type of thermoplastic polymer resin and polymer rubber that you want to mix, but usually suitable copolymers include, for example, styrene / ethylene-butylene block copolymer (SEBS) and its form modified with maleic acid; EPDM, EPDM / styrene or EPDM / acrylonitrile grafted copolymer and maleic acid modified forms thereof; a copolymer of styrene and maleic acid; reactive phenoxy thermoplastic resin; Maleic Acid Modified Ethylene Vinyl Acetate (EVA); and mixtures thereof. The amount of compatibilizing agent added is not specifically limited, but when used, it is usually from about 0.5 to about 10 parts by weight; preferably from about 3 to about 8 parts by weight, based on 100 parts by weight of the polymer component, in other words, the total amount of thermoplastic polymer resin and polymer rubber.

In relation to the polymers and / or elastomers indicated herein, the term “cured”, “vulcanized” or “crosslinked” refers to a chemical reaction involving the formation of bonds, for example, during chain growth or cross-links between polymer chains that contain the polymer or elastomer to such an extent that the elastomer undergoing such a process can provide the necessary functional properties, leading to a curing reaction, upon commissioning of the tire. For the purposes of the present invention, in order for the elastomeric composition to be considered “cured”, “vulcanized” or “crosslinked”, complete completion of such curing reactions is not required. For example, for the purposes of the present invention, a tire containing a composite interlayer based on the present invention is sufficiently cured when the tire component undergoes the necessary analyzes for product specifications during and after production and functions satisfactorily when used in a motor vehicle. Moreover, if the composition is satisfactorily, sufficiently or fully cured, cured or crosslinked, then the tire can be put into operation, even if the additional curing time can lead to the formation of additional cross-links.

Basically, polymer compositions, such as those used in tire manufacturing, are crosslinked in the final tire product. Crosslinking or vulcanization results in the inclusion of curing agents and / or accelerators; a common mixture of such agents is usually called a curing "system". It is known that the physical properties, performance, and wear resistance of vulcanized rubber compounds are directly related to the number (crosslink density) and types of cross bonds formed during the vulcanization reaction (see, for example, Helt et al., The post Vulcanization Stabilization for NR, RUBBER WORLD 18-23 (1991). Curing agents comprising the above components that promote or influence the curing of elastomers mainly include metals, metal oxides, catalysts, sulfur, peroxides and other commonly known in the art binder and curing agents as described above. Crosslinking or curing agents include at least one of, for example, sulfur, zinc oxide, and fatty acids, and mixtures thereof. Peroxide-containing curing systems may also be used. Generally, the polymer composition may crosslink by adding curing agents, for example, sulfur, metal oxides (i.e., zinc oxide, ZnO), organometallic compounds, radical initiators and the like, and heating the composition or mixture.

Using a method known as “dynamic vulcanization”, the dispersion process of the curing system is modified, as detailed below. Basically, the term “dynamic vulcanization” is used to mean a vulcanization process in which a thermoplastic technical resin and at least one vulcanizable rubber are mixed under conditions of high shear and elevated temperature in the presence of a curing agent or curing system for the rubber (s). As a result, the rubber is simultaneously crosslinked and dispersed in the form of particles, preferably in the form of a microgel, with a resin inside, which forms a continuous matrix. The resulting composition is known in the art as a “dynamically vulcanized alloy” or DVA. Usually, dynamic vulcanization is carried out by mixing the ingredients at a temperature that is equal to or higher than the rubber curing temperature and a temperature that is equal to or higher than the melting temperature of the resin, using equipment such as roller mills, Banbury® mixers, continuous mixers, plasticizers, mixing extruders (such as screw extruders). The unique characteristics of a dynamically vulcanized or cured composition are that in spite of the fact that the rubber is cured, the composition can be processed and processed using standard thermoplastic processing methods such as extrusion, injection molding, injection molding, etc. Waste and or scrap can also be collected and recycled. In a typical dynamic vulcanization process, the addition of a curing agent is selected so as to mix and vulcanize or crosslink at least one of the vulcanizable components in a composition containing at least one vulcanizable rubber, elastomer or polymer and at least at least one polymer or resin not vulcanizable using a vulcanizing agent (s) for at least one vulcanizable component. (See, for example, US 6079465 and the references therein). However, in the present invention, the dynamic vulcanization process is preferably further modified as described below in order to achieve the particular advantages derived from such a modification.

Conventional curing agents that may function in the present invention are as follows: ZnO, CaO, MgO, Al ₂ O ₃ , CrO ₃ , FeO, Fe ₂ O ₃ and NiO. These metal oxides can be used in conjunction with the stearic complex of the corresponding metal (for example, stearic salts of Zn, Ca, Mg and Al), or with stearic acid and, with both the sulfur compound and the alkyl peroxide compound (see also Formulation Design and Curing Characteristics of NBR Mixes for Seals, RUBBER WORLD 25-30 (1993). Often accelerators are added to the curing agent (s) to cure the elastomeric compositions. Curing agent (s) with or without at least one accelerator, often in the field of technology are called cure A “system” for elastomer (s). A curing system is used because more than one curing agent is usually used to achieve a positive result, especially when using a mixture of rubber with a high content of diene and a less reactive elastomer. Moreover, since the present Since the invention uses a specific DVA process, it is necessary that the properties of the curing system correspond to the mixing process so that the conditions of the invention are achieved. In particular, this DVA process utilizes the stepwise addition of a vulcanizable rubber component (s), where rubber (s) are added for dynamic vulcanization in the last two batches. Moreover, it is necessary that all rubber added in one stage be cured before the rubber (s) of the next stage are added, this period of time is characterized and determined by the residence time in the mixer. Usually in the first or, if there are more than two stages of adding rubber, then in the previous stage, the rubber (s) cures to about 50% of the maximum cure that a particular rubber and curing system can achieve, if independently determined, at the curing temperature, a dynamic vulcanization process in a period of time that is less than about the residence time in the mixer. For example, to determine the curing characteristics of the particular rubber (s) present in the composition, the rubber (s) and the curing system can be combined using methods known to one skilled in the art, for example on twin roll mills, a Banbury mixer, or a mixing extruder. A sample of the mixture, often called an “accelerated” compound, can be cured under static conditions, for example, in the form of a thin sheet, using a mold that is subjected to heat and pressure in the press. Samples of accelerated compounds, cured in the form of thin plates at gradually increasing times and / or high temperatures, are then analyzed for tensile strain properties and / or crosslink density to determine the curing state (described in detail in American Society for Testing and Materials, Standard ASTM D412).

Alternatively, an accelerated compound can be tested for cure using a curing analysis using a rotating disk rheometer (described in detail in American Society for Testing and Materials, Standard ASTM D2084). It has been found that the maximum degree of cure preferred for a dynamically vulcanizable first or previous step of adding rubber to a dynamically vulcanizable mixture is such that the degree of cure of this rubber (s) is selected from the group consisting of about 50%, for example, from about 60% up to more than 95%; from about 65% to about 95%; from about 70% to about 95%; from about 75% to more than about 09%; from about 80% to about 98%; from about 85% to about 95%; and from about 85% to about 99% in a period of time less than or nearly equal to the residence time in the mixer used for dynamic vulcanization. Subsequent additions of rubber (s) to the dynamically vulcanizable mixture are cured similarly to the following additions of rubber (s), if any. Therefore, at the conclusion of the dynamic vulcanization process, the vulcanizable rubbers added to the composition are fully cured to achieve the necessary properties of the thermoplastic composition, of which they are, for example, impermeable to fluids (gas or liquid), preferably a gas-tight layer for air, such as a layer for the tire. For the purposes of the present invention, this degree of cure may be termed "substantially fully cured".

It should be noted that vulcanized rubbers will be cured by at least 50% of the maximum cure level that they are capable of based on the curing system, time and temperature, and typically, the degree of cure of such rubbers will exceed 50% of the maximum cure. If the degree of cure of the rubber (s) added in one step has not reached at least 50% of the maximum level, coagulation of the dispersed rubber particles into larger particles is possible, which is undesirable. Conversely, it may be desirable to cure the rubber particles to a level less than the maximum cure level that the rubber is capable of, so that the flexibility measured, for example, using the Young's modulus of elasticity, the rubber component is a suitable level for final use in use, for example, as interlayers of a tire or component of a sleeve.

Therefore, it may be necessary to control the degree of cure of the rubber (s) used in the composition so that it is less than or equal to about 95% of the maximum degree of cure that it is capable of, as described above.

For the purpose of dynamic vulcanization in the presence of a technical resin, any suitable curing system capable of vulcanizing saturated or unsaturated halogenated polymers for vulcanizing at least an elastomeric halogenated C ₄ to C ₇ isomonoolefin copolymer and paraalkylstyrene, with the exception of peroxide curing agents, which are specifically excluded from use in the present invention, since if if one or more thermoplastic technical resins are present, such peroxides will cause crosslinking of these resins themselves. If the technical resin will cure itself or crosslink, this will lead to an overly cured, non-thermoplastic composition. Suitable curing systems for the components of the elastomeric halogenated copolymers of the present invention include zinc oxide in combination with zinc stearate and stearic acid and optionally one or more of the following accelerators or vulcanizing agents: Permalux (di-ortho-tolylguanidine salt of dicatecholborate); HVA-2 (m-phenylene bis maleimide); Zisnet (2,4,6-trimercapto-5-triazine); ZDEDC (diethylzinc dithiocarbomate) and also including other dithiocarbamates for the purposes of the present invention; Tetrone (dipentamethylene thiuram hexasulfide); Vultac 5 (alkyl phenol disulfide); SP1045 (phenol formaldehyde resin); SP1056 brominated alkyl phenol formaldehyde resin; DPPD (diphenyl phenylenediamine); salicylic acid; ortho-hydroxybenzoic acid; rosin; abietic acid; and TMTDS (tetramethylthiuram disulfide) used in combination with sulfur. However, in the present invention, due to the fact that each addition of vulcanizable rubber (s) must be cured by at least 50% of its or their maximum cure level under process temperature conditions until the next addition of rubber (s), that determined by the residence time in the mixer, it is also necessary to adjust the composition of the curing system to achieve such suitable results. The ways in which this can be achieved are usually known to the person skilled in the art and are further described in detail here, for example, using the set of methods set forth in ASTM D2084.

Curing accelerators include amines, guanidines, thioureas, thiazoles, thiurams, sulfenamides, sulfenimides, thiocarbamates, xanthates and others. Acceleration of the curing process can be achieved by adding an amount of accelerator to the composition. The mechanism for accelerating the vulcanization of rubber involves complex interactions between the curing agent, accelerator, activators and polymers. Ideally, the entire available curing agent is used, used in the formation of effective cross-links that connect the individual polymer chains to each other and increase the overall strength of the polymer matrix. Various accelerators which are known in the art include, but are not limited to, stearic acid, diphenylguanidine (DPG), tetramethylthiuram disulfide (TMTD), 4,4`-dithiodimorpholine (DTDM), tetrabutylthiuram disulfide (TBTD), 2,2` -benzothiazyl disulfide (MBTS), disodium salt of hexamethylene-1,6-bistiosulfate, 2- (morpholintio) benzothiazole (MBS or MOR) of 90% MOR and 10% MBTS (MOR 90), N-tertiarubityl-2-benzothiazolsulfene ) and N-oxydiethylene thiocarbamyl-N-oxydiethylene sulfonamide (OTOS), zinc 2-ethylhexanoate (ZEH), N, N`-diethylthiourea. Curing agents, accelerators, and curing systems of which they are part, are suitable with one or more polymers capable of forming cross-links, are well known in the art. The curing system can be dispersed at a suitable concentration into the required amount of the rubber component, optionally, the rubber component contains one or more fillers, additives and / or plasticizers by, for example, mixing the rubber and components of the curing system in the step before adding the rubber-containing composition to the thermoplastics using mixing equipment commonly used in rubber technology for such purposes as, for example, twin roll mills, a Benb mixer ri, mixing extruder, etc. Such mixing is commonly referred to as “acceleration” of the rubber composition. Alternatively, the rubber composition may be accelerated in a mixing step in an extruder before dynamic vulcanization is performed. It is particularly preferred that the curing system is dispersed in the rubber phase or rubber composition, also optionally including one or more fillers, additives and other conventional constituents for end use, before adding rubber to the thermoplastic resin (s) in the mixing equipment, in which requires dynamic vulcanization.

In one embodiment of the invention, at least one curing agent is typically present from about 0.1 to about 15 phr, alternatively from about 0.5 to about 10 phr.

Useful combinations of curing agents, curing modifiers and accelerators can be presented as follows: as the main vulcanizing agent of rubber, for example, sulfur vulcanizing agent, powdered sulfur, precipitated sulfur, highly dispersed sulfur, sulfur with a specially treated surface, insoluble sulfur, dimorpholindisulfide, alkyl phenol disulfide and mixtures thereof. These compounds may be used in an amount of from about 0.5 phr to about 4 phr (part by weight per 100 parts by weight of the elastomeric component). Alternatively, if, from the point of view of the other polymer and resin components present, such compounds are possible, then organic peroxide, benzoyl peroxide, t-butyl hydroperoxide, 2,4-dichlorobenzoyl peroxide, 2,5-dimethyl-2,5-di ( t-butylperoxy) hexane, 2,5-dimethylhexane-2,5-di (peroxybenzoate) and mixtures thereof. When used, such curing agents may be present at a level of from about 1 phr to about 20 phr. Other suitable curing agents include vulcanization agents of phenolic resins such as bromides of alkyl phenol resins or mixed crosslinking systems containing tin chloride, chloroprene or other halogen donors and an alkyl phenol resin and mixtures thereof. Such agents may be used at a level of from about 1 phr to about 20 phr. Alternatively, other suitable curing agents, curing agent modifiers and suitable levels of use include zinc oxide and / or zinc stearate (from about 0.05 phr to about 5 phr), stearic acid (from about 0.1 phr to about 5 phr), magnesium oxide (from about 0.5 phr to about 4 phr), lyserge (from 10 to 20 phr or so), p-quinondioxime, p-dibenzoylquinone dioxime, tetrachloro-p-benzoquinone, poly-p-dinitrosobenzene (from about 0 5 phr to about 10 phr), methylenedianiline (from about 0.05 phr to about 10 phr) and mixtures thereof. In addition, if necessary or necessary, one or more vulcanization accelerators can be added in combination with a vulcanizing agent, including, for example, aldehyde ammonia, guanidine, thiazole, sulfenamide, thiuram, dithic acid salt, thiourea, and mixtures thereof, for example, in an amount from about 0.1 pht to about 5 phr or more.

A dynamic vulcanization process suitable for preparing the compositions of the present invention includes those that are generally known in the art, for example, nylon plus brominated isobutylene and parameter styrene styrene (BIMS) copolymers, as well as the dynamic vulcanization process described herein by the authors in a simultaneously prepared application, entitled “Thermoplastic Elastomer Composition and Process for producing Same”, having patent attorney number PM-2004-149 included here, and also referred to as a “stepwise addition” method for including cheniya at least one component of the vulcanizable rubber or elastomer. Typically, the latter process uses several additions of at least one rubber component, preferably at least two such additions, although three, four or more may be used. However, in each case, staging depends on the vulcanization criterion, including the residence time in the mixer. As described herein, preferred polymer components contain isobutylene-containing copolymers as vulcanizable components (s), for example, halogenated butyl, such as chlorinated butyl or brominated butyl, and a brominated rubber copolymer of isobutylene and parameter methyl styrene, and a thermoplastic polymer such as nylon or a mixture of different nylons polymers. It is particularly preferred that the dynamically vulcanizable compositions of the present invention include rubber components in the form of a dispersed, almost completely cured, finely divided phase in a continuous matrix of a thermoplastic, such as nylon.

Regardless of theory, it is believed that the fine rubber dispersion thus obtained in the composition of the present invention is partly the result of a chemical reaction between, for example, benzyl bromine in BIMS or allyl halogen in halogenated butyl and terminal amines in polyamides at the phase boundary dispersed particles of rubber and thermoplastic formed during mixing. The presence of such interfacial reactions during mixing and simultaneous reactions of two immiscible polymers prevents the adhesion of small particles of the dispersed rubber phase, thus leading to particularly thin dispersions of the rubber phase. The presence of such interfacial reactions is usually called the “reaction combination” and is described, for example, in US patents Nos. 5571864 and 6469087, incorporated herein by reference. At the same time, again, regardless of theory, due to interfacial stability in reaction-combined immiscible systems, it is believed that the phase inversion of the highly concentrated component of the polymer mixture with a low viscosity, the rubber phase, is inhibited as a result of the stabilization effect of the interfacial combination.

Typically, in a polymer mixture based on two polymers of different viscosities, polymer physics dictates that a phase with a lower viscosity in such a mixture is continuous (see, for example, DR Paul and JW Barlow, J. Macromol. Sci., Rev. Macromol. Che., C18 (1980), 109; VI Metelkin and VS Blekht, Kolloid. Zh., 46 (1984), 476 and LA Ultracki, J. Rheol., 35 (1991), 1615). The key invention was the invention of A. M. Gessler, US Patent No. 3037954, which ultimately led to the introduction of commercial, dynamically vulcanizable alloys or DVA. Subsequent compositions based on EPDM and propylene have been successfully developed and commercialized (e.g. Santoprene®, Advanced Elastomer Systems), as a result of which the highly concentrated low viscosity EPDM component must be a dispersed phase by curing EPDM while mixing propylene and EPDM in mixer. Even in the absence of a reaction combination, vulcanization leads to a greater increase in viscosity; in other words, in fact, the viscosity of the cured component is very high and the thermoplastic phase can become a continuous phase. By determining how much is needed for phase inversion, the maximum rubber content of EPDM rubber in such systems can exceed more than 70 volume percent rubbers.

Moreover, regardless of the theory, according to the theory of packaging, it is believed that the maximum fractional volume of monodispersed spheres, which can be located in a fixed volume, based on close hexagonal packing arrangement, is 0.74 or 74% of the available volume. In addition, it is believed that the maximum fractional volume that can be achieved on the basis of disordered close packing and cubic packing of mono-dispersed spheres is 0.64 and 0.52, respectively. These calculations are described in R.K. McGeary, J. Am. Soc., 44 (1961), 513. In polymer mixtures, dispersions are polydispersed, which advantageously increase the filled volume of the fraction. Given these factors, it is expected that the maximum packaging volume of a polydispersed polymer in a double polymer mixture should be from about 70 to 80 volume percent. However, due to interphase stabilization that prevents phase inversion, the maximum rubber content in dynamically vulcanized polyamide / BIMS systems described in EP 857761A1 and EP 969039A1 is limited to less than 60 volume%.

By reducing the viscosity difference between the rubber or BIMS component and the components of the thermoplastic technical resin during mixing and / or processing, the uniformity and fineness of the morphology of the mixture increase, in other words, the fine, dispersed vulcanized rubber particles significantly increase the good mixing mechanics as well as the required permeability properties. However, due to the characteristics of flow activation and shear thinning inherent in BIMS polymers, the decrease in viscosity of BIMS polymers at elevated temperature and shear rates encountered during mixing are more pronounced than the decrease in viscosity of the thermoplastic component with which the BIMS polymer is mixed. Thus, from the point of view of reducing BIMS viscosity at high shear rates and temperatures, it is necessary to use either low molecular weight nylons that have lower viscosity, or nylons in combination with plasticizers, or a combination of the two approaches to reduce the viscosity more. Such an approximation is necessary to achieve a comparison, or approximation, of the viscosity of the BIMS polymer phase with the nylon resin phase in order to achieve dynamically vulcanizable mixtures of BIMS and nylon with acceptable dispersion sizes, for example as described in EP 0857761 A1 and EP 0969039 A1. Both options lead to a nylon phase with a compromise in mechanical properties, for example, due to the use of low molecular weight nylons and / or high permeability due to the use of conventional nylon plasticizers such as N-butylsulfonamide.

The present invention overcomes these limitations, along with other factors, by using, as plasticizers or viscosity modifiers, low molecular weight polyamides and processing enhancers for medium and high molecular weight nylons. When using nylon with medium and high molecular weight, the mechanical properties of the obtained vulcanized BIMS and nylon dynamically vulcanized mixtures or thermoplastic elastomers are not reduced. Moreover, low molecular weight polyamides exhibit relatively low permeability, so that the vulcanizable mixtures thus obtained do not have significantly impaired transmission properties. In other words, compared to using a conventional nylon plasticizer, such as N-butylsulfonamide, the compositions of the present invention exhibit the required level of impermeability, which is suitable for the manufacture of tire layers and other impermeable films from air, oxygen or fluids. In addition, the presence of low molecular weight polyamides in the thermoplastic elastomer composition of the present invention improves its solid state properties, especially wear resistance or fatigue resistance at low temperature, by lowering the low-temperature elastic modulus.

The present invention overcomes the limitations of the prior art in reducing the viscosity of high molecular weight polyamide thermoplastics to a level similar to halogenated isobutyl elastomers by using low molecular weight polyamides, which themselves exhibit low permeability properties, especially when compared to conventional plasticizers in the art. In addition, the present invention is also capable of producing thermoplastic elastomer compositions having a finely divided rubber domain that is simultaneously highly elastic. Plasticizers suitable for use in the composition of the present invention are generally defined as being compatible with the thermoplastic matrix, especially the nylon component (s). Such plasticizers include low molecular weight polyamides and the like. They are sold under various trade names, including “Sunmide” (Sanwa Chemical Industry Co., Ltd.) and Uni-Rez® (Arizona Chemical). Typically, low molecular weight polyamide plasticizers have an average molecular weight of less than or approximately equal to 20,000 daltons; such as from about 1000 to about 18000 daltons; preferably from about 3000 to about 17000 daltons. Such low molecular weight polyamide plasticizers have a flash point of more than 250 ° C (alternatively more than 275 ° C), a brittle temperature of less than -20 ° C (alternatively less than -25 ° C, alternatively less than -30 ° C), and a softening temperature of less than than 180 ° C (alternatively less than 170 ° C, alternatively less than 160 ° C). Moreover, low molecular weight polyamides suitable in the present invention preferably have a viscosity at 200 ° C. of less than about 15 Pascal · seconds (Pa · s); alternatively, from about 0.05 to about 12 Pa · s; preferably from about 0.2 to about 10 Pa · s. Suitable commercially available products covering the entire above range of viscosities include: Sunmide product code 15, 15K-5, 52, and 72; 300; 500; 550; NT-110; 130K; 180D; 140E; 140RK-20 and 100G, exhibiting viscosities in the range from about 0.25 Pa · s to about 0.60 Pa · s, measured at 190 ° C; and from about 0.4 Pa · s to about 15 Pa · s, measured at 200 ° C; and Uni-Rez types 2611-2722, and especially including type 2614 having a viscosity of about 1.1, type 2633, which has a viscosity of about 4.3, and type 2653, having a viscosity of about 7.5, all measured at 200 ° C. The analysis used was Brookfield's usual LVT, rod # 31, according to ASTM D 3236; the standard analysis temperature was 190 ° C; however, the analyzes were also carried out in the range of temperatures of interest, including 200 ° C. Typically, the plasticizer is from about 0.5% to about 10%; preferably from about 1% to about 8%; more preferably from about 2% to about 5% by weight of the total composition. Alternatively, a low molecular weight polyamide plasticizer can be used at a concentration greater than zero to about 20 weight percent of the total weight of the high molecular weight thermoplastic or nylon (s) present in the composition; alternatively, greater than about 15 weight percent, based on the weight of said nylon; for example, at a concentration selected from the group consisting of a permutation and combination of a lower concentration of about 0.5, about 1.0, and about 2 weight percent and a higher concentration of about 12, about 15, and about 20 weight percent. As mentioned earlier, mainly plasticizer is used to improve the processing of the composition during preparation of the composition, and its subsequent processing into a layer or sheet, including mixing, calendaring, etc.

The decrease in viscosity of nylon or a mixture of types of nylon can be directly determined by mixing the plasticizer with nylon before dispersing it and determining the resulting viscosity of the composition or mixture. In this case, the viscosity of the plasticized high molecular weight nylon composition is "complex" viscosity and can be determined at, for example, 230 ° C using a viscometer with plane-parallel plates at 1 radian per second; The standard analysis method is described in ASTM D 4440 and ISO 6721. The complex viscosity of a polymer or composition containing a polymer is a frequency-dependent function determined during forced harmonic shear stress fluctuations. Commercial equipment such as Rheometrics Scientific ARES DMA is available for measuring complex viscosities. Using various types of low molecular weight nylon as a plasticizer at a concentration of 10 weight percent, it has been determined that suitable viscosity reductions in high molecular weight thermoplastics, especially nylon, can affect the decrease compared with the composition in the absence of plasticizer. Typically, reductions of from about 5 to about 70% can be achieved; more preferably from about 9 to about 68%; most preferably from about 10% to about 65%. These reductions, compared to those that can be achieved using a conventional nylon plasticizer, N-butylsulfonamide, are better by about 12% when turned on at a concentration of about 14 weight percent. In fact, the data indicate that low molecular weight polyamides are more effective plasticizers, since a smaller amount is required to achieve the same plasticization effect as when using N-butylsulfonamide. Moreover, as described herein, the additional benefits of the physical and impermeability properties of the dynamically vulcanized compositions of the present invention are enhanced by the use of low molecular weight polyamides. In particular, it is contemplated that the permeability of a dynamically vulcanized composition of the present invention, suitable for use as an air, oxygen or liquid impermeable layer when using a low molecular weight polyamide plasticizer, can exhibit permeability values from about 75% to about 175% compared to that practically does not contain a plasticizer, preferably practically does not contain a low molecular weight polyamide plasticizer, suggesting that such a composition can be successfully received. Alternatively, the dynamically vulcanized composition of the present invention may exhibit superior (low) permeability compared to a similar composition using a prior art plasticizer such as N-butylsulfonamide. The permeability of the composition of the present invention can usually be from about 10 to about 95 percent of the plasticized composition of the prior art (in other words, the plasticized composition in the complete absence of low molecular weight polyamide); preferably from about 20 to about 90 percent; more preferably from about 25 to about 85 percent. Alternatively, variation in the choice of nylon type can be made to optimize the physical or other properties and / or the selected amount of low molecular weight polyamide plasticizer in order to obtain a dynamically vulcanized composition having similar or equal permeability properties acceptable for use in those compositions to which they are added, against comparison compositions using N-butylsulfonamide.

Dynamic vulcanization can be carried out in various types of commercial equipment mainly available in the rubber or plastic industry, including an internal Banbury mixer, a roller mixer and mixing extruders. The preferred mixing equipment is a double worm extruder with cross worms. Basically, the mixing is carried out during such temporary and temperature conditions that the dispersed rubber particles are hardened to the extent necessary to maintain their stability, for example, to prevent adhesion of such particles before or during the addition of the next rubber stage, if stepwise mixing is used, or mixing the composition. A suitable dynamic vulcanization temperature range is usually from about the melting point of the thermoplastic or nylon resin (ol) to about 300 ° C. For example, the temperature may vary from about the melting temperature of the matrix resin (ol) to about 275 ° C. Preferably, dynamic vulcanization is carried out at a temperature range of from about 10 ° C. to about 50 ° C. above the melting temperature of the matrix resin or, in the case of a mixture, the most refractory resin. A more preferred mixing temperature is from about 20 ° C to about 40 ° C above the melting point of the polyamide or mixed thermoplastic polyamide matrix.

In one embodiment of the present invention, the required amount of cross-linking agent (s) or curing system is dispersed into the elastomeric component by mixing a cross-linking agent capable of forming cross-linking in the elastomeric component at a low to medium temperature before contacting the thus formed elastomeric component, with a rubber component (s) to cure the mixture. Moreover, when the elastomer is added to the resin in stages or in batches until the desired composition is fully achieved, each portion of the rubber composition may be the same or, if desired, the amount of curing system present in the rubber portion may be varied to achieve the desired effect, for example, large or smaller portions of the crosslinking agent of the elastomer. Using this method, the cross-linking agent almost does not interact with rubber, and is not able to partially react with a thermoplastic resin, causing both a decrease in molecular weight and the formation of cross-links in the resin. Moreover, control over the speed and degree of crosslinking in the elastomeric component is achieved more easily.

The process of obtaining a composition of thermoplastic elastomer can be performed by the following procedure. First, mixing equipment, such as a Banbury mixer, twin roll mills, etc., is used to pre-mix the elastomeric component and a predetermined amount of cross-linking agent to form a substantially uniform dispersion. At this time, the required amount of an optional filler, such as carbon black, modified carbon black, clay or modified clay, oil or a plasticizer not used for the elastomer, can be added to the elastomeric component. During this mixing step, the temperature should be controlled at a sufficiently low level for the particular elastomer (s) selected for reasons of activity of the curing system in order to avoid premature cross-linking in the elastomers. Suitable temperature during this mixing step may be less than about 120 ° C.

The required amount of the cross-linking agent-containing elastomeric component thus obtained and the predetermined amount of thermoplastic, preferably nylon resin (s), are preferably loaded into a twin-screw mixing extruder or other mixing device capable of dynamically vulcanizing under controlled conditions. The rubber component is dynamically crosslinked by mixing the molten resin (s) in such a way as to cause the dispersion of the elastomeric component as a dispersed phase (domain) into the nylon component, which forms the dispersing phase or matrix.

In addition, various fillers other than vulcanizing agents can be added to the nylon resin or elastomeric component during the above mixing, but it is preferable to mix them prior to the dynamic vulcanization step. In particular, the low molecular weight polyamide can be mixed with the nylon resin (s) before adding the nylon component (s) to the mixer, for example a mixing extruder, to mix with the rubber component and conduct dynamic vulcanization, or the low molecular weight polyamide can be added together with the nylon resin ( ammonia), for example, during mixing, for example, into the hopper of a mixing extruder together with nylon granules. The mixing equipment used to dynamically vulcanize the nylon resin and the elastomeric component is not particularly limited, and for example includes a screw extruder, a plasticizer, a Banbury mixer, a two-screw mixing extruder and the like. Among these dynamic vulcanization equipment, it is most preferable to use a twin screw mixing extruder. Otherwise, two or more types of mixers may be used for successful mixing. As conditions for the dynamic vulcanization step, melt mixing of the resin (s) is included, the temperature being at least the temperature at which the selected nylon resin or resin mixture melts, but preferably above the melting temperature, as described above. Moreover, the shear rate at the mixing time is usually greater than about 500 s ^-1 ; preferably from about 500 s ^-1 to about 7500 s ^-1 ; otherwise from about 1000 s ^-1 to about 7500 s ^-1 ; for example, from about 2000 s ^-1 to about 7500 s ^-1 . The total mixing time during dynamic vulcanization or its each stage, if stepwise mixing is used, preferably from about 30 seconds to about 10 minutes.

If the dynamic vulcanization process used involves the multistage addition of the rubber component to the resin (s) or resin (s) with a previously dynamically vulcanized and dispersed elastomer, then the above stage of dynamic vulcanization is repeated with one or more additional portions of the rubber composition until it is achieved all the necessary amount of rubber in the final thermoplastic composition. Therefore, the step-by-step process includes at least two stages, but can be carried out in more than two stages, for example, three, four, five or more, if necessary. Moreover, the amount of rubber introduced in each stage of the rubber can vary, ensuring that the full required amount of rubber in the final composition is achieved as a result of all mixing operations, and a suitable amount of rubber introduced in each stage of the rubber is such that the desired particle size is achieved in the final composition and a large volume percentage of rubber.

The thermoplastic elastomer composition thus obtained has such a structure that the elastomeric component forming the dispersed phase is dispersed as a dispersion phase (domain) in the nylon resin matrix, which forms the dispersing phase. As a result of dynamic vulcanization, the composition remains thermoplastic, and films, layers or sheet-like structures can be obtained by conventional molding, extrusion or rolling.

The described composition may have one or more fillers, such as calcium carbonate, clay, mica, silicon and silicates, talc, titanium oxide, starch and other organic fillers, such as wood flour and carbon black. Suitable fillers include gas duct black, furnace black, thermal black, acetylene black, flame black, modified carbon black, such as silicon treated or silicon coated carbon black (described, for example, in US patent No. 5916934, which is incorporated into this description by links), etc. Improved carbon black is preferred. Also, fillers may include various improved or unimproved substances, such as silicon, clay, calcium carbonate, talc, titanium oxide, and the like. Fillers may be present at a level of from 0 to about 30 weight percent based on the rubber present in the composition.

Also, layered, intercalated or dispersed clays may be present in the composition. These clays, also called “nanoclay”, are well known, and their properties, production methods and mixtures with polymers, for example, are described in JP 2000109635, JP 2000109605, JP 11310643; DE 19726278; WO98 / 53000; and US Pat. , magadite, kenyait, stevensite, etc., along with vermiculite, halloysite, aluminum oxides, hydrotalcites, etc. These layered clays are mainly composed of particles containing a plurality of silicon wafers bonded together, typically having a thickness, in one embodiment, from about 4 to about 20 Å, and in another embodiment, from about 8 to about 12 Å, and containing exchange ions such as Na ⁺ , Ca ²⁺ , K ⁺ and Mg ²⁺ present between the layers.

Layered clays can be intercalated and stratified by treatment with organic molecules (a component that promotes swelling), capable of entering into ion-exchange reactions with cations present between the layers in the layered silicate. Suitable swelling aids include cationic surfactants such as ammonia, alkylamines or alkylammonium (primary, secondary, tertiary or quaternary), phosphonium or sulfonium derivatives of aliphatic, aromatic or arylaliphatic amines, phosphines or sulfides. Suitable amino compounds (or the corresponding ammonium ion) are those compounds whose structure is R ₁ R ₂ R ₃ N, where R ₁ , R ₂ and R ₃ are C ₁ to C ₃₀ alkyl or alkenes, which may be the same or different. In one embodiment, the exfoliating agent is a so-called long chain tertiary amine, where at least R ₁ is C ₁₂ to C ₂₀ alkyl or alkene.

Another class of swelling promoting agents includes those compounds that can be covalently attached to the surface between the layers. Such compounds include polysilanes of the structure Si (R`) <sub>2</sub> R <sub>2</sub> , where R` is the same or different at each location and is selected from alkyl, alkoxy or oxysilane, and R ² is an organic radical compatible with the polymer matrix of the composite. Other swelling agents include protonated amino acids and their salts containing 2-30 carbon atoms, such as 12-aminododecanoic acid, ε-caprolactam and the like. Suitable swelling agents and a process for intercalating layered silicates are described in US 4,472,538, 4,810,734, 4,889,885 and WO92 / 02582.

In a preferred embodiment, swelling agents are combined with a halogenated polymer. In one embodiment, the agent includes all primary, secondary, and tertiary amines and phosphines; alkyl and aryl sulfides and thiols; and their multifunctional versions. Preferred additives include: long chain tertiary amines such as N, N-dimethyloctadecylamine, N, N-dioctadecylmethylamine, dihydrogenated fatty alkyl methylamine and the like. and an amine ending in tetrahydrofuran; long chain thiol and thiosulfate compounds, such as sodium hexamethylenetiosulfate. In another embodiment of the invention, improved intrapolymer impermeability is achieved by using multifunctional additives such as hexamethylene bis (sodium thiosulfate) and hexamethylene bis (cinnamaldehyde).

The amount of layered, intercalated or dispersed clays included in the composition according to the present invention is the amount necessary to exhibit an improvement in the mechanical properties or insulating properties of the composition, for example, tensile strength or permeability of air / oxygen. Typically, the amounts may be, in one embodiment, from 0.5 to about 15 weight%, or in another embodiment, from about 1 to about 10 weight%, and in yet another embodiment, from about 1 to about 5 weight%, based on the content polymer in the composition. Expressed in parts per hundred parts of rubber, layered, intercalated or dispersed clay in one embodiment may contain from about 1 to about 30 phr and in another embodiment from about 3 to about 20 phr. In one embodiment, the layered clay is an alkylamine layered clay.

The degree of cure of vulcanized rubber can be described in terms of gel content, crosslinking density, amount of extractable component, or can be based on the degree of cure that can be achieved for rubber when cured in the absence of resin. For example, in the present invention, it is preferred that the halogenated elastomer achieves from about 50 to about 85% of the total cure per elastomer per se, as measured, for example, by tensile strength or by analysis using an oscillating disk cure meter (ASTM D 2084, a standard method for vulcanizing properties of rubber using a curing meter using an oscillating disk).

By molding the thermoplastic elastomer composition into a sheet, film or tube using a T-shaped slotted mouthpiece, a straight mouthpiece or a transverse head mouthpiece, a cylindrical mouthpiece for injection molding, and the like. at the end of a single screw extruder or by rolling, it is possible to use the composition as a layer preventing the permeability of air, for example, a layer of a pneumatic tire, and as a component of a sleeve layer, and the like. The thermoplastic elastomeric compositions of the present invention can be combined into a filament, granulated, then molded using a single screw extruder, which is commonly used for resin.

Thus obtained sheet or tubular molded product can be effectively used as a layer of a layer of a pneumatic tire, or an inner layer of a sleeve, or a coating of a sleeve of a gas-tight sleeve. Moreover, the low permeability properties of the composition are suitable for use with fluids other than gases, such as fluids such as water, hydraulic fluid, brake fluid, heat transfer fluid and the like, ensuring that the layer in direct contact with fluid, had the required resistance to the fluid used.

Any ranges of numbers listed in the description above or in the claims and claims hereinafter related to various aspects of the invention, such as representing a specific set of properties, units of measure, conditions, physical conditions or percentages, are intended to be literally included here explicitly with by reference or otherwise, any number falling within such a range, including a subset of numbers or ranges belonging to any category within the range, is listed in this way. Moreover, the term “about”, used as a modifier for something or in conjunction with something, as a variable of characteristic or condition, is intended so that the numbers, ranges, characteristics and conditions described here are flexible, and when the use by a specialist of the present invention using temperatures, times, concentrations, amounts, contents, number of carbon atoms, properties such as particle size, surface area, volume weight, etc., which are out of range or differ from a single value The desired result was achieved, namely, a dynamically vulcanized composition containing at least one isobutylene-containing rubber and at least one thermoplastic, such as nylon, suitable for use, for example, as a layer of a tire or otherwise in pneumatic tires or in the sleeves.

EXAMPLES

The following commercially available products were used as components in the examples:

Rubber components Description Bims Exxpro ^TM 89-4 (copolymer of brominated isobutylene and p-methylstyrene, 0.75% Br, 5% PMS, ExxonMobil Chemical) Curing System Components Zno Zinc oxide - a component of the curing system St acid Stearic acid - a component of the curing system Znst Zinc - a component of the curing system S sulfur is a component of the curing system MBTS 2.2`-benzothiazyl disulfide sulfur-containing accelerator of the curing system Additional components Struktol 40MS Combining compound (mixture of dark aromatic hydrocarbon resin, Struktol Company) Calsol 810 naphthenic oil fraction (Calumet Lubricants) Fllector Flector TMQ antioxidant (1,2-dihydro-2,2,4-trimethylquinoline polymer, Flexsys America) N660 Carbon black (semi-active) T1 SP1068 (tackifier 1 - alkylphenol formaldehyde resin, Schenectady International) T2 G100 (tackifier 2 - synthetic polyterpene resin (Quintone brand, Nippon Zeon Chemicals)) T3 Sylvalite RE100L (tackifier 3 - Wood Resin Pentaerythrol Ether, Arizona Chemical) Technical Resin Component N11 Nylon 11, available as Rilsan BESN O TL from Arkema N6 / 66-1 Nylon 6/66 copolymer available as Ube 5033B from Ube N6 / 66-2 Nylon 6/66 copolymer available as Toray's CM6001FS Additional component P1 Plasticizer, BM4, N-butylsulfonamide C1 Combining Agent, AR201, Maleated EVA Copolymer (Mitsui-DuPont) S1 Stabilizer 1, Kit includes Irganox, Tinuvin, and Copper Iodide (CuI) Low molecular weight polyamide M1 “Sunmide 15K-5,” Mw = 15000, density = 0.97, softening point = 160 ° C., viscosity at 200 ° C. = 0.4-0.9 Pa · s, available from Sanwa Chemical. M2 “Sunmide550,” Mw = 10000, density = 0.94, softening point = 110 ° C., viscosity at 200 ° C. = 0.4-0.8 Pa · s, available from Sanwa Chemical. M3 “Unirez 2653,” density = 0.96, softening point = 95-105 ° C., viscosity at 200 ° C. = 7.5 Pa · s, available from Aizona Chemical. M4 “Unirez2614,” density = 0.98, softening point = 123-133 ° C., viscosity at 200 ° C. = 1.1 Pa · s, available from Aizona Chemical. M5 “Unirez 2633,” density = 0.97, softening point = 127-137 ° C., viscosity at 200 ° C. = 4.3 Pa · s, available from Aizona Chemical.

Mixtures of nylon and a low molecular weight polyamide plasticizer are prepared and viscosities are measured. The mixing data and proportions are presented in table 1. As shown in table 1, the viscosity of N6 / 66-1 decreases with the addition of either low molecular weight polyamide or plasticizer P1, however, low molecular weight polyamide is more effective than plasticizer P1 in lowering the viscosity of nylon. Low molecular weight polyamide viscosity modifiers are mixed with nylon using a Brabender mixer operating at 60 rpm and 220 ° C for 5 minutes.

Table 1 Nylon Component (s) Modifier (weight%) Viscosity * (Pa · s) N6 / 66-1 No 1953 N6 / 66-1 PI (14%) 1719 N6 / 66-1 Ml (10%) 720 N6 / 66-1 M3 (10%) 1681 N6 / 66-1 M4 (10%) 1744 * complex viscosity is measured at 230 ° C using a Rheometric ARES rheometer with parallel plate geometry at 1 Hz (no ASTM number)

In accordance with the compositions listed in table 2 (all amounts in phr, unless otherwise indicated), examples 1-3 are prepared using a two-screw extruder for dynamic vulcanization at 230 ° C. The amounts of modifier and plasticizer are selected so as to equalize the viscosity between nylon and BIMS rubber. The following mixing cycles are used in each of the following examples: BIMS rubber is pre-mixed with curing agents using an internal Banbury mixer. For examples 1-3, the elastomeric components and the curing system are loaded into the plasticizer, mixed for 3.5 minutes and discharged at about 90 ° C. Then the mixture is granulated using a rubber granulator. For examples 4-6, BIMS rubber is pre-mixed with curing agents using a Banbury mixer operating at 100 rpm for 3 minutes with a loading temperature of 100 ° C. Subsequently, the rubber is granulated using a granulator. Pre-mixing of nylons with a low molecular weight polyamide plasticizer and stabilizers is carried out using a Japan Steel Works, Ltd. two-screw extruder. Model 44 (JSW-44) at 210 ° C. With simultaneous use in one stage, all pre-mixed nylons, pre-formed rubber plates and coupling agents are fed to the JSW double-screw extruder for examples 1-3 and ZSK-30 double-screw extruder for examples 4-6 at an extrusion temperature of 210 to 220 ° C. For all examples, good extrusion quality was obtained and the mechanical properties of their films are also listed in Table 2. It was shown that low molecular weight polyamide modifiers are as effective as a plasticizer that helps mix nylon with BIMS rubbers. In addition, using low molecular weight polyamide modifiers can be obtained low modulus material at -20 ° C.

table 2 Example (phr) one 2 3 Bims one hundred one hundred one hundred Zno 0.15 0.15 0.15 St acid 0.60 0.60 0.60 Znst 0.30 0.30 0.30 Nil 17.9 19.0 19.0 N6 / 66-2 53.3 57.9 57.7 PI 11.6 0 0 Cl 9.3 8.4 8.4 Ml 0 5.7 0 M2 0 0 5.7 SI 0.54 0.57 0.57 M50 RT (MPa) 5.9 6.3 7.7 EB RT (%) 390 356 294 M50 -20 ° C (MPa) 19.6 16.3 16.9 EB -20 ° C (%) 373 349 303 M50 means 50% modulus measured at room temperature (RT) or -20 ° C according to ASTM D412-92; EB means tensile elongation measured at room temperature (RT) or -20 ° C according to ASTM D412-92.

As shown in table 3, without modifiers viscosity reduction N6 / 66, in example 5 using a screw extruder ZSK-30 at 220 ° C was obtained weak miscibility. The addition of plasticizers N11 and P1 can lower the viscosity of all nylon, nylons N6 / 66 and 11 and leads to good dispersion with 56% vulcanized BIMS rubber in Example 4. However, the same blending quality can also be achieved using 10% M5 in N6 / 66 without any amount of N11 plasticizer. Without the use of a plasticizer, which reduces the permeability of the composition, Example 6 showed a significant decrease in permeability.

Table 3 Example (phr) four 5 6 Bims one hundred one hundred one hundred Zno 0.15 0.5 0.5 St acid 0.60 1,5 1,5 Znst 0.30 0 0 Nil 40,4 0 0 N6 / 66-1 27.8 80.8 72.7 PI 11.0 0 0 Cl 10.1 0 0 M5 0 0 8.1 SI 0.51 0.50 0.50 The volume of rubber% 56 56 56 Morphology Good Bad Good G ¹ (-20 ° C) * 12.7 NM * 25.3 Permeability** 14.0 NM 6.0 * G` = dynamic shear modulus in MPa, measured with a mechanical dynamics analyzer at 1 Hz in twisting mode. ** Permeability = oxygen permeability at 60 ° C, measured by Mocon in units of cc-mils / m ² -day-mmHg.

All described documents are incorporated into this description by reference, including any priority documents and / or analysis procedures to determine that they do not contradict this text. The principles, preferred embodiments and methods of carrying out the present invention are described in the foregoing description. Despite the fact that the invention has been described with reference to private options, it should be understood that these options only explain the principles and areas of applicability of the present invention. In this regard, it should be understood that various modifications of illustrative options can be made, and these other layouts can be developed without departing from the essence and scope of the invention, as defined in the attached claims. In addition, the term “comprising” is considered synonymous with the term “comprising” for Australian law.

Various aspects or variations of the present invention are set forth in the following paragraphs.

1. The composition of thermoplastic elastomer containing

(A) at least one halogenated isobutylene-containing elastomer; and

(B) at least one nylon resin having a melting point of from about 170 ° C to about 260 ° C; and

(C) a plasticizer containing a polyamide having a weight average molecular weight of 20,000 daltons or less; Where:

(1) at least one of said elastomer is present as the dispersed phase of the fine vulcanized particles in the dispersed phase of said nylon; and

(2) said elastomer particles were obtained by dynamic vulcanization.

2. The composition according to claim 1, where the specified plasticizer has srednevekovoi molecular weight from 1000 to 18000 daltons.

3. The composition according to claim 1 or 2, wherein said plasticizer has a viscosity at 200 ° C. of less than about 15 Pa · s.

4. The composition according to claim 3, where the specified viscosity is from about 0.05 to about 12 PA · s.

5. The composition according to claim 3, where the specified viscosity is from about 0.2 to about 10 Pa · s.

6. The composition according to claim 1, 2, 3, 4 or 5, where the degree of vulcanization of said elastomer particles is not less than about 50% of the maximum degree of vulcanization that said elastomer can achieve based on the composition and the conditions under which said elastomer is vulcanized .

7. The composition according to claim 6, where the specified degree of vulcanization is selected from the group consisting of from about 60% to more than about 95%; from about 65% to about 95%; from about 70% to about 95%; from about 75% to more than about 90%; from about 80% to about 98%; from about 85% to about 95%; and from about 85% to about 99%.

8. The composition according to claim 6, where the specified degree of vulcanization is at least 80%.

9. The composition according to claim 1, 2, 3, 4, 5, 6, 7 or 8, further containing at least one component selected from the group consisting of fillers and combining agents.

10. The composition according to claim 1, 2, 3, 4, 5, 6, 7, 8 or 9, where the specified nylon resin contains a mixture of (i) nylon 11 or nylon 12; and (ii) a nylon 6/66 copolymer, and the ratio (i) / (ii) in the composition is from about 10/90 to about 90/10.

11. The composition of claim 10, where the specified ratio (i) / (ii) in the composition is from about 30/70 to about 85/15.

12. The composition according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or 11, where at least one of the specified halogenated isobutylene-containing elastomer is selected from the group consisting of halogenated butyl rubber, a halogenated copolymer isoolefin and para-alkyl styrene; halogenated isobutylene-p-methyl styrene-isoprene copolymer; halogenated branched butyl rubber; and halogenated star-branched butyl rubber.

13. The composition according to p. 12, where the specified halogenated butyl rubber has a high content of the following halogenated structure, where X represents halogen:

14. The composition according to item 12 or item 13, where the halogen is selected from the group consisting of bromine and chlorine.

15. The composition according to item 12, where these halogenated copolymers of isoolefin and para-alkylstyrene are copolymers containing from ₄ to ₇ isoolefin.

16. The composition of claim 15, wherein said halogenated isoolefin-para-alkyl styrene copolymer is a halogenated poly (isobutylene-co-p-methylstyrene) copolymer.

17. The composition according to clause 16, where the specified halogen is bromine.

18. The composition of thermoplastic elastomer containing

(A) at least one halogenated isobutylene-containing elastomer; and

(B) at least one nylon resin having a melting point of from about 170 ° C to about 260 ° C and having a complex viscosity; and

(C) a plasticizer suitable for reducing the complex viscosity of said at least one nylon resin while substantially maintaining the level of oxygen permeability available for a substantially similar composition in the substantially complete absence of said plasticizer; Where:

(1) at least one of said elastomer is present as the dispersed phase of the fine vulcanized particles in the dispersed phase of said nylon; and

(2) said elastomer particles were obtained by dynamic vulcanization.

19. The composition of claim 18, wherein said complex viscosity of said at least one nylon resin in the presence of said plasticizer is reduced from about 5% to about 75% compared to said nylon in the substantially complete absence of said plasticizer.

20. The composition of claim 19, wherein said decrease is from about 7% to about 70%.

21. The composition of claim 19, wherein said decrease is from about 9% to about 68%.

22. The composition of claim 19, wherein said decrease is from about 10% to about 65%.

23. The composition according to p. 18, 19, 20, 21 or 22, where the permeability of the composition with respect to oxygen is from about 75% to about 175% of that which the composition has in the substantially complete absence of said plasticizer.

24. The composition of claim 18, 19, 20, 21, 22 or 23, wherein the degree of vulcanization of said elastomer particles is not less than about 50% of the maximum degree of vulcanization that said elastomer can achieve based on the composition and the conditions under which said the elastomer is vulcanized.

25. The composition according to paragraph 24, where the specified degree of vulcanization is selected from the group consisting of from about 60% to more than about 95%; from about 65% to about 95%; from about 70% to about 95%; from about 75% to more than about 90%; from about 80% to about 98%; from about 85% to about 95%; and from about 85% to about 99%.

26. The composition according to paragraph 24, where the specified degree of vulcanization is at least 80%.

27. The composition according to p. 18, 19, 20, 21, 22, 23, 24, 25 or 26 further comprises at least one component selected from the group consisting of fillers and combining agents.

28. The composition according to p, 19, 20, 21, 22, 23, 24, 25, 26 or 27, where the specified nylon resin contains a mixture of (i) nylon 11 or nylon 12; and (ii) a nylon 6/66 copolymer, and the ratio (i) / (ii) in the composition is from about 10/90 to about 90/10.

29. The composition of claim 28, wherein said composition ratio (i) / (ii) in the composition is from about 30/70 to about 85/15.

30. The composition according to p, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28 or 29, where at least one of these halogenated isobutylene-containing elastomer is selected from the group consisting of halogenated butyl rubber, a halogenated copolymer of isoolefin and para-alkyl styrene; a halogenated isobutylene-p-methyl styrene-isoprene copolymer; a halogenated branched butyl rubber; and a halogenated star-branched butyl rubber.

31. The composition according to claim 20, where the specified halogenated butyl rubber has a high content of the following halogenated structure, where X represents halogen:

32. The composition according to item 30 or item 31, where the halogen is selected from the group consisting of bromine and chlorine.

33. The composition according to p. 30, where these halogenated copolymers of isoolefin and para-alkylstyrene copolymers contain isoolefin from C ₄ to C ₇ .

34. The composition according to p. 33, where the specified halogenated copolymer of isoolefin and para-alkylstyrene contains a halogenated poly (isobutylene-so-p-methylstyrene) copolymer.

35. The composition according to clause 34, where the specified halogen is bromine.

36. Pneumatic tire containing a layer that prevents the penetration of air, containing a composition of thermoplastic elastomer according to any one of claims 1 to 35.

37. A sleeve containing a thermoplastic elastomer composition according to any one of claims 1 to 35 as a layer of a sleeve or hose material.

Claims (19)

1. The composition of thermoplastic elastomer for use as a layer of tires or a protective layer containing
(A) from 50 to 80% by weight of at least one halogenated isobutylene-containing elastomer; and
(B) from 20 to 50% by weight of at least one nylon resin having a melting point of from about 170 ° C to about 260 ° C; and
(C) from 0.5 to 10.0 wt.% A plasticizer containing a polyamide having a weight average molecular weight of 20,000 Da or less;
and
(D) a curing system;
where the wt.% based on the total weight of the composition, where:
(1) at least one of said elastomer is present as the dispersed phase of the fine vulcanized particles in the dispersed phase of said nylon; and
(2) said elastomer particles were obtained by dynamic vulcanization. 2. The composition according to claim 1, where the specified plasticizer has a weight average molecular weight of from 1000 to 18000 Yes. 3. The composition according to claim 1, where the specified plasticizer has a viscosity at 200 ° C of less than about 15 Pa · s. 4. The composition according to claim 1, where the degree of vulcanization of said elastomer particles is not less than about 50% of the maximum degree of vulcanization that said elastomer can achieve based on the composition and the conditions under which said elastomer is vulcanized. 5. The composition according to claim 1, where the specified nylon resin contains a mixture of (i) nylon 11 or nylon 12; and (ii) a nylon 6/66 copolymer, and the ratio (i) / (ii) in the composition is from about 10/90 to about 90/10. 6. The composition according to claim 1, where at least one of the specified halogenated isobutylene-containing elastomer is selected from the group consisting of halogenated butyl rubber, halogenated isoolefin and para-alkyl styrene copolymer, halogenated isobutylene-p-methyl styrene-isoprene copolymer, halogenated butylated branched halogenated star-branched butyl rubber. 7. The composition according to claim 6, where the specified halogenated butyl rubber is contained in an amount of from 60 to 95% of the following halogenated structure,

where X is halogen. 8. The composition according to claim 7, where the halogen is selected from the group consisting of bromine and chlorine. 9. The composition according to claim 6, where these halogenated copolymers of isoolefin and para-alkylstyrene are copolymers containing from C ₄ to C ₇ isoolefin. 10. The composition according to claim 1, where the specified composition is included in the product, which is a tire or sleeve. 11. The composition of thermoplastic elastomer for use as a layer of tires or a protective layer containing
(A) from 50 to 80% by weight of at least one halogenated isobutylene-containing elastomer; and
(B) from 20 to 50% by weight of at least one nylon resin having a melting point of from about 170 ° C to about 260 ° C and having a complex viscosity, where the complex viscosity is a frequency-dependent function determined during forced harmonic voltage fluctuations during shear of nylon resin; and
(C) from 0.5 to 10.0% by weight of a plasticizer suitable for reducing the complex viscosity of said at least one polyamide resin while substantially maintaining the permeability level with respect to oxygen available for a substantially similar composition at, essentially the complete absence of the specified plasticizer;
(D) a curing system;
where the wt.% based on the total weight of the composition
and
where: (1) at least one of the specified elastomer is present as the dispersed phase of the fine vulcanized particles in the dispersion phase of the specified nylon; and
(2) said elastomer particles were obtained by dynamic vulcanization. 12. The composition of claim 11, wherein said complex viscosity of said at least one nylon resin in the presence of said plasticizer is reduced from about 5% to about 75% compared to said nylon with substantially no said plasticizer. 13. The composition according to claim 11, where the permeability of the specified composition with respect to oxygen is from about 75% to about 175% of that which has the specified composition in the essentially complete absence of the specified plasticizer. 14. The composition of claim 11, wherein the degree of vulcanization of said elastomer particles is not less than about 50% of the maximum degree of vulcanization that said elastomer can achieve based on the composition and the conditions under which said elastomer is vulcanized. 15. The composition according to claim 11, where the specified nylon resin contains a mixture of (i) nylon 11 or nylon 12; and (ii) a nylon 6/66 copolymer, and the ratio (i) / (ii) in the composition is from about 10/90 to about 90/10. 16. The composition according to claim 11, where at least one of said halogenated isobutylene-containing elastomer is selected from the group consisting of halogenated butyl rubber, halogenated isoolefin and para-alkyl styrene copolymer, halogenated isobutylene-p-methyl styrene-isoprene copolymer, halogenated butylated branched halogenated star-branched butyl rubber. 17. The composition according to clause 16, where the halogen is selected from the group consisting of bromine and chlorine. 18. The composition according to clause 16, where these halogenated copolymers of isoolefin and para-alkylstyrene are copolymers containing from C ₄ to C ₇ isoolefin. 19. The composition of thermoplastic elastomer for use as a layer of tires or a protective layer, mainly consisting of a dynamically vulcanized mixture:
(A) about 55% by weight of brominated isobutylene-p-methylstyrene elastomer; and
(B) about 40 wt.% Resin nylon copolymer 6/66; and
(C) about 4 wt.% Plasticizer, mainly consisting of nylon resin having a viscosity at 200 ° C of about 4 Pa · s
(D) a curing system; and
(E) fillers;
where the specified elastomer is present as the dispersed phase of the small dynamically vulcanized particles in the dispersion phase of the specified nylon; and
where the specified dynamic vulcanization is carried out in a twin-screw extruder.