RU2686097C1 - Method of producing rubber with low cold flow - Google Patents

Abstract

FIELD: manufacturing technology.SUBSTANCE: invention relates to production of rubber of general and special purpose with controlled value of cold flow. Disclosed is a method of producing rubber with low cold flow, where the rubber is selected from a group comprising polybutadiene rubber, butyl rubber, polyisobutylene rubber. Method comprises adding a layered silicate suspension to a polymerisate formed during polymerisation when producing rubber, wherein the silicate is added to the polymerisate in the form of a suspension when the desired conversion of the monomers for the given polymerisation process is achieved. Invention also discloses modified rubber obtained by said method, rubber mixture containing one or more of said rubber, and article made from appropriate rubber mixture.EFFECT: obtained modified rubber has low cold flow with preservation of micro- and macrostructural characteristics, which improve operational characteristics of rubber technical articles based on the disclosed rubbers.18 cl, 1 dwg, 7 tbl, 37 ex

Description

Scope of invention

The invention relates to the field of production of general and special purpose rubbers with adjustable cold flow value. More specifically, the invention relates to the production of modified rubbers with low cold-flow properties, as well as rubber compounds containing such modified rubbers. The invention can be used in the synthetic rubber industry, and the resulting modified rubbers can be used both independently and as part of composite elastomeric materials for the production of rubber products (RTI) and tires with improved performance characteristics.

The level of technology

Polybutadiene rubber, polyisobutylene rubber and butyl rubber due to the complex of their unique characteristics are widely used in the manufacture of tires and rubber products (RTI). However, many brands of these rubbers have increased cold fluidity, which leads to certain problems during their isolation, storage and transportation, namely: increased fluidity at normal temperature and relatively small loads makes it difficult to isolate and store the rubbers themselves, and also in some cases rubber. mixtures based on them.

Due to good resistance to aging, mineral oils, acids and chemical environments (excluding hydrocarbons), ozone, water, as well as ultra-low gas, vapor and water permeability, polyisobutylene rubbers and butyl rubbers have a high performance under the influence of various factors. In addition, as a result of the vulcanization of these rubbers, elasticity, electrical resistivity and resistance to abrasive wear, acids and thermal aging are increased. Due to these qualities, these elastomers are widely used in industry.

Butyl rubber is used for the manufacture of automotive chambers, hoses, conveyor belts, for insulation of electrical cables, lining of tanks, etc. It is known that butyl rubber is characterized by increased cold flow, and this creates certain problems during its isolation, drying, packaging and transportation (P.A. Kirpichnikov et al. / Chemistry and Technology of Synthetic Rubber, p. 322, second paragraph; Ullmann's Encyclopedia of Industrial Chemistry. Rubber, 5. Solution Rubbers, Vol. 31, p. 671, column 2, second paragraph.

High molecular weight polyisobutylene is used for the manufacture of chemically resistant sheet and waterproofing materials, rubberized fabrics, electrical insulating materials, sealants, adhesive tapes. Hydrocarbon solutions and aqueous dispersions of polyisobutylene are used as adhesives in the manufacture of artificial fur, suede and other textile-based materials, as well as impregnating compositions in the production of paper and asbestos board. (See http://www.performancechemicals.basf.com/ev/internet/polyisobutene/en/content/EV3/polyisobutene/applications];

http://adhesives.specialchem.com/tech-library/article/polyisobutylene-as-a-base-polymer-and-modifier-for-adhesives-and-sealants).

Polyisobutenes are used for lining or insulation of various vessels, pipes, hoses, etc. (See: http://www.stroitelstvo-new.ru/kauchuk/sintez.shtml ; http://www.siginsulation.co.uk /show_prod.asp?ProdID=2600&CatID=20&SubCatID=127).

However, some brands of polyisobutylene have increased fluidity. The introduction of active fillers (such as carbon black, graphite, talc) increases the strength and rigidity of the compositions, reduces flowability, but also reduces the resistance of the polymer to light and atmospheric oxygen. (See: http://bibliotekar.ru/spravochnik-52/5.htm ).

Polybutadiene rubbers are used in large quantities in mixtures with other elastomers, to give the tire rubber good hysteresis, abrasion resistance and to improve resistance to cracking. Polybutadiene rubber improves frost-resistant properties and resistance to heat aging of rubber and tires. Polybutadiene rubbers are widely used for the production of automobile tires, as well as for the manufacture of conveyor belts, insulation of electrical cables, cold-resistant products, products with high dynamic endurance and wear resistance, etc. [P.A. Kirpichnikov et al. / Chemistry and Technology of Synthetic Rubber, p. 293, paragraph 2 below]. However, the lack of branching of the molecular chains and low thermoplasticity determine the high cold flow properties of these rubbers during their storage and transportation [Ullmann's Encyclopedia of Industrial Chemistry. Rubber, 5. Solution Rubbers, Vol. 31, p.659, 1 column, first paragraph, lines 21-26).

A common disadvantage of butadiene rubbers (mainly obtained on neodymium-containing catalytic complexes), polyisobutylene rubbers and butyl rubbers is their low cohesive strength and high cold flow. In the prior art there are various approaches to solving this problem.

Thus, in patent document WO 2004/003038 A1 discloses a method of balanced improvement of processability and lowering of the fluidity of butyl rubber (BK), including the production of butyl rubber with an increased (up to 2.5 mol.%) Content of C ₄ -C ₁₄ multiolefin units, most often isoprene . The technical result is achieved by increasing the content of C ₄ -C ₁₄ -multiole compounds and using as a regulator of the degree of polymerization 2,4,4-trimethyl-1-pentene (TMP). The degree of cold flow of the samples was evaluated by increasing the area under the relaxation curve when determining the Mooney viscosity in comparison with the area under the relaxation curve for standard butyl rubber (reference sample). The technology of obtaining BC in this document allows to reduce cold flow three and more times. The disadvantage of this method in comparison with the standard technology of obtaining BK is the increased content in the copolymer of C ₄ -C ₁₄ -multiole oleic units, most often isoprene, which negatively affects the thermal, ozone, and heat resistance of BK. A different approach is presented in international application WO 0216452 A1, in which, in addition to adding an agent of a polymerisation degree regulator (2,4,4-trimethyl-1-pentene), to improve processability and reduce cold flow of butyl rubber, it is branched using bifunctional monomers, in particular divinylbenzene (DVB). The technical result of this technical solution is the possibility of varying the rheological and cohesive properties of rubber by means of a branching controlled by means of a molecular weight regulator. The technical result is achieved by introducing a branching bifunctional monomer added to the monomer mixture prior to the polymerization process, as well as by controlling the intensity of the reaction by a chain transfer agent (TMP) and selecting the optimum temperature. In the obtained samples of butyl rubber, the cold flow, estimated from the change in the area under the relaxation curve, is reduced by 5-7% by weight. The main disadvantages of this method include the use of DVB as a crosslinking agent. In the copolymerization, divinylbenzenes act as cross-linking agents, and the effectiveness of their isomers increases in the order: o- divinylbenzene < m- divinylbenzene < p- divinylbenzene. Technical grades of divinylbenzenes can contain 20-25, 50-60 and about 80% of the meta- and para-isomers in a mixture with ethylvinylbenzene and practically have no analytically stable isomeric composition, and therefore, the butyl rubber obtained by the presented method will not have stable output characteristics [ cm. Encyclopedia of Polymers, vol. 1, M., 1972, p. 695; Kirk-Othmer encyclopedia, v. 21, NY 1983, p. 796.]. It should be noted that the branching of the BC with the improvement of its technological characteristics may adversely affect the performance properties of rubber.

It is known that various branching agents of post-polymerization modification, for example, chlorides of phosphorus, tin, silicon and other compounds, are used to reduce the cold flow of cis-1,4-polybutadiene [L. basis of neodymium and their application ", 2001: p. 56]. However, these methods also lead to an undesirable substantial change in the macrostructure of the polymer.

Another solution is presented in patent RU 2442796 C1, p. 4, lines 2-25, where the authors seek to reduce the cold-flow properties of the SKD-ND butadiene rubber to values less than 25 mm / h by modifying rubber with unsaturated polyketones. The modification is carried out at the conversion of butadiene-1,3 not lower than 95%. Low molecular weight unsaturated polyketones used as a modifier are liquid oligomers. The disadvantage of this invention can be attributed to the presence of a large number of double bonds in the molecules of the polyketone, as well as oxygen-containing functional groups, which can lead to a decrease in thermal, heat, atmospheric, and ozone resistance of rubber and products based on it.

Another technical solution to reduce the cold fluidity of polybutadiene rubber is disclosed in patent RU 2087489 (see RU 2087489 C1, p. 1, Abstract; pp. 3-4 examples 2, 6). According to this decision, cis-1,4-polybutadiene is obtained by polymerization of 1,3-butadiene in an aromatic solvent in the presence of a Ziegler-Natta system as a catalyst based on compounds of rare-earth elements. At the end of the process, polymeriz cis-1,4-polybutadiene is mixed with a solution of polyhexene-1 in an aromatic solvent. The optimal dosage of polyhexene is 5-20 wt. hours per 100 wt. including polybutadiene and allows you to control the ductility of the elastomer, as well as lower the cold flow of polybutadiene to values less than 7 mm / h. The disadvantages of the claimed method include the need to obtain polyhexene-1 with the specified characteristics, which in practice leads to the complexity of the technology and the increase in production costs. Moreover, the addition of polyhexene-1 can worsen the physico-mechanical properties of the final product due to the decrease in the proportion of polybutadiene in the mixture, and as a result, the density of the vulcanization network is reduced, since polyhexene does not contain double bonds capable of making it co-vulcanized with butadiene rubber molecules.

Document RU 2127280 C1 describes another method for producing cis-1,4-polybutadiene with reduced cold flow (see RU 2127280, p. 3, column 1, lines 32-62; p. 6 table 2). In this method, butadiene is polymerized under the influence of a catalytic complex preformed in the presence of a diene (butadiene, piperylene, isoprene) consisting of rare earth carboxylate, a halogen-containing organoaluminum compound and an organoaluminum compound. In this case, the halogen-containing compound is served either only during the preparation of the catalytic complex, or also additionally during the polymerization process during the conversion of monomer 50-85%. In addition, during the polymerization process, instead of the specified chlorine-containing compound, a compound selected from the group comprising: benzyl chloride, tert-butyl chloride, ethyl chloride, propyl chloride, isobutyl chloride, ethyl aluminum sesquichloride (EASC), isobutyl aluminum sesquichlor, izobutyl chloride, and izobutyl chloride, applied to the isobutyl chloride, Isobutyl chloride, ethyl chloride, ethyl chloride, propylene chloride, isobutyl chloride;

The resulting polymers have low ductility, cold flow, and vulcanizates based on them exhibit high physical and mechanical properties. So, by changing the amount of chlorine-containing compound and the exposure time of the reaction mass after the introduction of the modifier, it is possible to reduce cold flow from 31.3 mm / h (when using EASAC) to 1.05 mm / h. In this patent there is no information about the molecular-mass characteristics and polydispersity of the rubbers presented, which does not allow an unequivocal conclusion about the reasons for such a significant change in the cold-flow behavior of rubbers. However, it is obvious that such a significant change in the composition of the initiating system leads to a change in the micro- and macrostructural characteristics of the resulting rubber, which, on the one hand, reduces cold flow, and on the other, has a negative effect on performance.

In patent RU 2099359 C1 discloses a method of obtaining cis-1,4-diene rubber by polymerizing a diene in an aromatic solvent using a catalyst based on neodymium-containing compounds and triisobutyl aluminum (see RU 2099359, p. 5, claim 1, p. 7 , table 2). The presented method differs in that a polymerizate at the end of the polymerization process or in the rubber obtained at subsequent stages of the processing process is injected with a quinol ether toluene solution of the formula:

where R is tert-butyl,

in the amount of 0.01-1.0% wt. based on the monomer.

The introduction of this compound reduces the cold flow of the product from 28.6 mm / h to 6 mm / h.

The disadvantages of this method include branching of polymer chains, partial structuring of rubber containing the compound during processing and contamination of working solvent or waste water with a modifier or its decomposition products

In the above-described approaches to the reduction of cold-fluidity of rubbers, no mention is made of improving processability without changing their micro- and macrostructures, improving the barrier properties, and / or increasing fatigue endurance and weather resistance of rubbers based on them.

From the prior art it is known the filling of rubbers with layered silicates at the stage of preparation of rubber mixtures with the aim of improving their physico-mechanical properties. From the information of the prior art in the use of layered silicates in polymer chemistry, it follows that clay is used mainly to improve the barrier properties of plastics and rubbers, for example, their gas impermeability. There is also an improvement in the processability of rubbers and rubber mixtures filled with layered silicates (clays), an increase in the resistance to crack propagation during repeated bending.

The introduction of layered silicates into rubber, such as organoclays, for example, due to the anisotropy of their particles, can improve the weather resistance and improve the technological characteristics of rubbers and rubber mixtures based on them [Sadhu S, Browmick AK / Unique rheological behavior of rubber based nanocomposites . // J. Polymer Sci., Part B: polymer Phys., 43, 1859, 2005].

So in the patent US 8476352 B2 disclosed that the addition of from 5 to 10% wt. organoclays of the brand Cloisite Na ⁺ , introduced into the elastomer directly at the stage of preparation of the rubber mixture, can improve the manufacturability of the rubber mixture and improve the air-tightness of rubber.

In the method disclosed in US 2005/0282948, in situ (co) polymerization of the monomers is used together with the organoclay. The described method relates to rubbers obtained by anionic solution copolymerization of two monomers selected from among butadiene, isoprene, styrene, etc. The main advantage of polymers containing organoclay is improved mechanical properties and increased barrier properties. However, the main disadvantage of this method is the introduction of organoclays in the initial stages of the polymerization process, which negatively affects the activity of the initiating system, since it requires an increase in consumption and adjustment of its composition. In addition, anionic polymerisation in situ in the presence of organoclay leads to a significant undesirable change in the macro- and microstructure of the rubbers [Maiti M., Bhattacharya M., Bhowmick AK / Elastomer Nanocomposites // Rubber Chemistry and Technology. -2008. - V. 81. - N. 3. - P. 404, 418; M. Liao, W. Shan, J. Zhu, Y. Li, and H. Xu, J./Polym. Sci., Part B: Polym. Phys. 43, 1344, 2005; Z. Zhang, L. Zhang, Y. Li, and H. Xu, / Polymer 46, 129, 2005].

WO 2007/109877 (A1) describes a method for in situ copolymerization of a C4-C8-isoolefin monomer and a C4-C14-multiolefin monomer in the presence of an organoclay. The main purpose of this invention is to increase the barrier properties of butyl rubber or bromobutyl rubber. The method involves dispersing Cloisite ^® organoclay in methyl chloride in an amount of 5-7% by weight. from the expected amount of polymer based on butyl rubber obtained in the copolymerization process, carrying out the copolymerization process to a conversion of up to 75% and, if necessary, bromination. In this way, a polymer is obtained containing effectively intercalated and partially exfoliated organoclay. The obtained polymers have improved barrier properties, their breathability was 2.7 * 10 ^-8 (cm ² / atm / s), versus 3.4 * 10 ^-8 (cm ² / atm / s) for a control sample of rubber that does not contain organoclay . This method of polymerization requires the use of exclusively tertiary amines modified clays. Considering the possibility of negative influence of the moisture content in the composition of clays on the molecular mass characteristics of the polymer and on the activity of the initiating system, preliminary preparation (drying) of clays is required prior to their use. In addition, this invention does not apply to the method of synthesis of butyl rubber / halobutyl rubber at temperatures above -90 ° C.

The filling of rubbers with layered silicates at the stage of preparation of rubber mixtures provides the improvement of certain rubber characteristics mentioned above. However, this method of filling rubbers does not solve the problem of their cold flow during storage and transportation.

From the prior art it is known that in order to reduce cold flow of 1,4-cis-butadiene rubbers and butyl rubbers, various methods of chemical and physical modification are used by introducing special substances both into the reaction mass at the stage of rubber synthesis and into the polymerizate at high degrees of monomer conversion ( s) or after polymerization, as well as by changing the composition of the initiating systems. The main thing in the chemical modification of rubbers is the change in the micro- and macrostructure of the rubbers, which in the future may have a negative impact on the performance properties of the products. The methods of physical modification allow one to influence the cold flow of a polymer in a directed way, without leading to a change in its micro- and macrostructure.

In addition, it is desirable that when modifying 1,4-cis-butadiene rubbers, butyl rubbers and polyisobutylene rubbers, along with a decrease in their cold flow, other important technical properties of rubbers and products based on them are also improved.

Thus, there is a need to develop new methods for the directed modification of 1,4-cis-butadiene rubbers, butyl rubbers and polyisobutylene rubbers, with the aim of reducing their cold flow without changing the micro- and macrostructural characteristics, which further improve other performance characteristics of rubber for tires and rubber-based such rubbers.

Summary of Invention

The technical task of the present invention is to develop a method of directed physical modification of 1,4-cis-butadiene rubbers, butyl rubbers and polyisobutylene rubbers in order to reduce their cold flow without changing the micro- and macro-structural characteristics, while further improving other performance characteristics of rubber for tires and rubber based on such rubbers.

The problem is solved using a controlled physical modification of 1,4-cis-butadiene, butyl and polyisobutylene rubbers and other elastomers with high cold fluidity according to the present invention. In one of the embodiments of the invention, it is proposed to obtain rubbers, in particular, selected from the group including: polybutadiene rubber, butyl rubber, polyisobutylene rubber, where the method includes the introduction of a suspension of layered silicate into the polymerizate formed during the polymerization process during the production of rubber, followed by stabilization, degassing, isolation and drying of the obtained product, at a level of monomer conversion of at least (0.95 ÷ 1.0) × X (%). At the same time X means target conversion for the chosen polymerization process, in which the corresponding rubber is obtained. Here, under the target conversion should be understood as a given conversion in accordance with the technological mode of obtaining rubber.

In another embodiment of the invention, modified cold flow composites obtained by the method of the present invention are provided.

In addition, the present invention provides rubber compounds for the manufacture of products containing one or more of such modified rubbers, as well as products made from such a rubber mixture. In some embodiments of the present invention, said product is an element of a tire, in particular a tire sidewall, a tire tread or a tire pressure layer.

The invention provides for obtaining rubbers with improved technological properties, first of all, low cold flow properties, and rubbers based on them with improved performance characteristics. This is facilitated by the uniform distribution of layered silicates in the polymerizate, which is also accompanied by intercalation and partial exfoliation of their particles in the polymer matrix and the formation of a skeleton limiting the fluidity of polymer macromolecules during storage and transportation, on the one hand, and the improvement of the barrier and other physicomechanical properties of rubber with other.

The field of application of the obtained modified rubbers is, in particular, the manufacture of rubber products (RTI) and automobile tires (trucks, for agricultural machinery and cars). Rubber for rubber goods and tires made using such rubbers will have lower gas permeability, improved processability, increased fatigue endurance, which guarantees an increase in reliability and / or service life of the product as a whole.

Brief Description of the Drawings

Figure 1 shows the dependence of the cold fluidity of SKD-ND rubber on the content and type of layered silicate.

Detailed Description of the Invention

Certain terms and concepts used in this application have the following meanings, as defined below.

The term "polymerizat" refers to a reaction mass based on a hydrocarbon solvent with partially or fully polymerized (s) monomer (s). Depending on the type and properties of the final product required, the degree of monomer conversion (s) can vary from 5 to 99% by weight.

The term "rubber solution" refers to a solution of rubber in a hydrocarbon solvent. To obtain it, the rubber is crushed and dissolved with stirring in a hydrocarbon solvent.

The term "wt. hours per 100 wt. "rubber", used in the text of the present invention, means the number of parts of any component of the rubber mixture per hundred parts of rubber, and is a unit of measurement adopted in the art.

As indicated above, in the main embodiment of the invention, physical modification of 1,4-cis-butadiene, butyl and / or polyisobutylene rubbers is carried out in the process of their preparation by introducing a suspension of layered silicate into the polymerized material in a monomer conversion of not less than (0, 95 ÷ 1.0) × X%, preferably not less than (0.95 ÷ 0.98) × X%. At the same time X means target, i.e. specified in accordance with the technological regime, the conversion achieved in the polymerization process upon receipt of the selected rubber.

For example, in the synthesis of 1,4-cis-butadiene rubbers, the target conversion of X is (95 ÷ 100)%, most preferably 99-100%. When the solution polymerization of polyisobutylene and butyl rubbers, the target X conversion is (5 ÷ 100)%, most preferably 10-80%, and even more preferably 20-40%.

At conversion levels below the specified range, the introduction of a suspension of layered silicate can lead to significant undesirable changes in the micro- and macrostructure of rubber, initiate chain transfer processes, or cause premature termination of the polymerization process. To eliminate the latter, special preparation of layered silicate may be required, for example, thorough drying, which will increase production costs. At conversion levels above the specified range, difficulties may arise in the distribution of the suspension of organoclay in the polymerizate due to an increase in the viscosity of the medium. In addition, at higher degrees of conversion, the possibility of polymerization in the interlayer space of clays is minimized or eliminated, which provides additional intercalation and exfoliation of their particles. Moreover, in some cases, an increase in conversion is difficult due to the approach to the maximum achievable under given polymerization conditions.

This modification method can be used to obtain linear and branched 1,4-cis-butadiene rubbers, polyisobutylene rubbers and butyl rubbers, which are distinguished by increased cold-flow properties, such as poly-1,4-cis-butadiene rubbers SKD-ND, polyisobutylene rubbers of the brands P-85 (PIB HRD-800), P-200 (PIB HRD-950) PIB-1300 and others, including butyl rubbers, characterized by lower molecular weight and / or Mooney viscosity, whose cold flow is more pronounced, such as BK-157 ° C (IIR 1570). At the same time, physical modification by layered silicates is most preferable for linear linear 1,4-cis-polybutadiene rubbers obtained by ion-coordination polymerization using neodymium, cobalt and other catalysts with a content of 1,4-cis units of at least 95% wt. ; linear butyl rubbers with a content of polyolefin monomer (usually isoprene) in the amount of 1.0-2.5 wt.%, and polyisobutylene rubbers.

The fundamentals of the methods for producing all the above listed rubbers are described in detail in the publications [P. Kirpichnikov et al. / Chemistry and Technology of Synthetic Rubber, p. 322-324, paragraph 2.9. 1 and 2 paragraph, paragraph 2.9.2; Ullmann's Encyclopedia of Industrial Chemistry. Rubber, 5. Solution Rubbers, Vol. 31, p.658-663, 671-676], which are incorporated into this description by reference in its entirety.

The rubbers to be modified according to the present invention belong to the group of rubbers obtained by the method of solution polymerization. So, synthetic cis-butadiene SKD-ND rubber, containing not less than 96% of 1,4-cis-units, is a product of butadiene polymerization in solution on ion-coordinating catalytic systems. The polymerization medium is formed by a hydrocarbon solvent.

Butyl rubber can be obtained by cationic solution copolymerization of isobutylene with olefin monomers, usually isoprene, in an environment of a hydrocarbon solvent in the presence of an organoaluminum catalyst at temperatures from minus 100 ° C to minus 55 ° C [see US 6,630,553 B2, incorporated herein by reference in its entirety] and temperatures from minus 90 ° C to minus 35 ° C in the presence of a catalytic system based on an organic boron compound and an organic acid [see WO 03037940 A1; WO 02059161 A1, included in the present description by reference in its entirety].

Also copolymers of isobutylene with olefins (butyl rubber), can be obtained according to patent RU 2124527 C1, included in the present description by reference in its entirety (see page 2, abstract), by polymerization and copolymerization of isobutylene in the medium of hydrocarbon solvents in the presence of Lewis acid and modifier. As a Lewis acid, either a complex of titanium tetrachloride with aluminum triisobutyl in combination with a modifier, or a complex of titanium tetrachloride with an alkyl aluminum halide is used. As a modifier, 2,6-ditertbutyl, or 4-methylphenol, or 2,2-methylene bis (4-methyl-6-tert-butylphenol), or tetraethoxysilane, or boron trifluoride are proposed.

To obtain high molecular weight polyisobutylene, isobutylene can be polymerized in a hydrocarbon solvent in the presence of Friedel-Crafts catalysts at temperatures ranging from 0 ° C to minus 100 ° C [see WO 03062284 A2, included in the present description by reference in its entirety]. Thus, physical modification according to the claimed method can be subjected to rubbers from the group of 1,4-cis-butadiene, polyisobutylene and butyl rubbers, obtained in solution using various types of catalytic systems described in the literature, including in patent sources, in particular, cited above .

Physical modification by layered silicates according to the proposed method is also possible in the synthesis of various chemically modified grades of 1,4-cis-butadiene, polyisobutylene, butyl rubbers, for example, solution polybutadiene marks SKD-ND (BR-1243Nd mark B), SKD-6 (SDK-6 -EF), SKD-7 (SKD-Nd-EF-40), Buna CB24, Nd-PBR, brominated butyl rubber, and others.

The content of the polymer in the solution of rubber or polymerizate may be 3-75% by weight, preferably 5-50% by weight, most preferably 7-20% by weight.

Unmodified and modified silicate materials with a particle size of not more than 100 nm can be used as a layered silicate. For example, unmodified layered silicates can be clays, in particular, smectic, for example, montmorillonites, hectorites, serpentinites, etc., in particular, unmodified bentonite (montmorillonite). In another embodiment, layered silicates, the so-called organoclays, modified with quaternary ammonium salts can be used. As an unmodified montmorillonite, it is possible to use layered silicate "Bentonite" produced by LLC Altai Raw Materials Company (Russia) and others like it. Of the organoclays, organoclays are sold under such trademarks as Dellite® (Dellite®72T; Dellite®67G, etc.) manufactured by Laviosa Chimica Mineraria S.p.A. (Italy); Cloisite® (Cloisite®10A, Cloisite®15A, Cloisite®20A, Cloisite®30A, Cloisite®93A, etc.) manufactured by Rockwood (USA); Metamon ™ and others.

Preferably, the layered silicate is selected from the group consisting of montmorillonite clays, kaolinite clays, chlorite clays, hydromicas, and mixed-layer minerals.

Aliphatic, alicyclic, aromatic hydrocarbons, chlorinated hydrocarbons, as well as their mixtures in various ratios can be used as a dispersion medium for preparing a suspension of layered silicate. In particular, suitable hydrocarbons are aliphatic hydrocarbons, such as pentane, isopentane, hexane, heptane, cycloheptane, cyclohexane, methylcyclohexane, cycloheptane, isooctane, n-octane, hexane-heptane fraction of hydrocarbons in different ratios of hexane to heptane; aromatic hydrocarbons such as benzene, toluene, xylenes, ethylbenzene, diethylbenzene, isobutylbenzene; petroleum ether; inert C1-C4 halogenated hydrocarbons, such as dichloromethane, ethyl chloride, methylene chloride, chloromethane.

In the case of modification of 1,4-cis-polybutadiene rubber, the most suitable medium for obtaining a suspension of layered silicate are hexane, heptane, cyclohexane and toluene, and mixtures thereof. In the case of modification of butyl rubber and polyisobutylene rubber, hydrocarbons such as pentane, isopentane, their mixtures, xylene, toluene, as well as various inert C2-C5 halogenated hydrocarbons used as polymerization medium can serve as the most suitable medium for preparing the suspension of silicate. Synthetic and mineral oils, such as aromatic oils, naphthenic oils, paraffin oils, such as, for example, MES (Mild Extraction Solvate), TDAE (Treated Distillate Aromatic Extract), RAE (Residual Aromatic Extract), can also be used as a dispersion medium. , DAE (Distillate Aromatic Extract). Examples of oils used may be products known under the trademarks Norman, Vivatec (500, 200), Enerthene 1849-1, Nytex (4700, 8450, 5450, 832), Tufflo (2000, 1200) and others. In addition, to prepare slurry of layered silicate as a dispersion medium can use the resulting polymerizate. Preferably, the polymer is characterized by a monomer conversion of at least (0.95 ÷ 1.0) × X%, where X is the target, i.e. specified in accordance with the technological mode, the conversion for the selected polymerization process.

The dispersion medium for the suspension of the layered silicate, as well as the medium for the polymerization and the medium for the rubber solution are selected on the basis of the technical requirements for the polymer synthesis process and the final product.

A suspension of layered silicate is prepared by dispersing the silicate in a dispersion medium, for example in hydrocarbon solvents, with stirring for 10-90 minutes at a temperature of from minus 90 to plus 100 ° C. It should be noted that the temperature of the preparation of a suspension of clay depends on what temperature is maintained during the polymerization of the modified polymer, and on the properties of the suspension medium.

In one of the embodiments of the claimed invention, the obtained modified rubbers contain 1.0-50% wt. layered silicates.

The increase in the content of layered silicate over 50% wt. it is possible, but not advisable, since at the same time there is no further reduction in cold flow, since the material is already at 50% wt. the content of a layered silicate loses its ability to flow when tested according to GOST 19920.18-74 (cold flow is 0 mm / h), but at the same time polymer processability or rubber properties based on rubbers containing more than 50% by mass of silicate may deteriorate.

In addition, when the content of layered silicates in the modified rubber is more than 30% wt. deterioration of the strength and hysteresis characteristics of rubber, based on such rubbers, is observed.

The content in the modified rubber of layered silicates is less than 1.0 wt.%, Regardless of the brand of layered silicate, does not lead to a decrease in the cold-flow properties of rubber and an improvement in the properties of rubbers obtained on its basis.

Physical modification of rubber is carried out by introducing 5-50% wt. slurry of layered silicate prepared by dispersing silicate in hydrocarbon solvents with stirring for 10-90 minutes at a temperature from minus 90 to plus 100 ° C, into the polymer during the monomer conversion of at least (0.95 ÷ 1.0) × X (% ) (where X is the target, ie, specified in accordance with the technological mode, the conversion for the selected polymerization process). So, during the synthesis of 1,4-cis-butadiene rubbers X = (95 ÷ 100)%, most preferably 99-100%, whereas in the solution polymerization of polyisobutylene and butyl rubbers X = (5 ÷ 100)%, most preferably 10-80 %, and even more preferably 20-40%, before or after stopping (termination of polymerization) and the introduction of antioxidant. As mentioned above, the temperature of the preparation of a suspension of clay depends on the temperature maintained by the polymerization of the modified polymer, and on the properties of the hydrocarbon suspension medium. When preparing a suspension of layered silicate to modify 1,4-polybutadiene rubber, temperatures of 15-100 ° C are most acceptable, and in the case of modification of polyisobutylene or butyl rubber - from -90 to -15 ° C

Moreover, aliphatic (pentane, isopentane, hexane, heptane, isooctane, n-octane, petroleum ether, hexane-heptane fraction of hydrocarbons in various ratios of hexane to heptane, etc.), alicyclic (cycloheptane, cyclohexane, methylcyclohexane, cycloheptane, etc.), aromatic hydrocarbons (benzene, toluene, xylenes, ethylbenzene, diethylbenzene, isobutylbenzene, etc.), inert halogenated hydrocarbons C1-C4 (chloromethane, chloromethylene, dichloromethane, chloroethane, etc.), and mixtures thereof Razl LfTetanus composition in accordance with the selected polymerization technique.

In another embodiment of the invention, the technical result is achieved by physical modification of rubbers by introducing a suspension of layered silicate prepared by dispersing the silicate in a part of a polymerizate or a rubber solution containing 5-180% by weight. layered silicate in the calculation of the polymer, which is part of this part of polymerizate or rubber solution, with stirring for 10-90 minutes at a temperature of from -90 to +100 ° C, into the polymerizate during monomer conversion (0.95 ÷ 1.0) × X (%), where X is the target, i.e. specified in accordance with the technological mode, the conversion for the selected polymerization process. In the synthesis of 1,4-cis-butadiene rubbers X = (95 ÷ 100)%, most preferably 99-100%, in solution polymerization of polyisobutylene and butyl rubbers X = (5 ÷ 100)%, most preferably 10-60%, and more preferably 20-40%, before or after termination of the polymerization and the introduction of the antioxidant.

At the end of the process, antioxidants may be added to the polymer in an amount of from 0.2 to 3.0% by weight. by weight of rubber contained in polymerizate. The most effective and appropriate dosage of antioxidant is 0.3-1.5% by weight, more preferably from 0.2-0.4% by weight. As antioxidants for rubber, compounds of the phenol or amine type, or any other antioxidants, including mixtures, recommended for stabilization of rubbers are used.

 Examples of phenolic antioxidants are: 2,6-di-tert-butyl-4-methylphenol (ionol, agidol 1, alkofen, antioxidant); 2,2-di- (4methyl-6-tert-butylphenol) methane (antioxidant 2246, Agidol 2, Bisalkofen), 2-methyl-4,6-bis (octylsulfonylmethyl) phenol (IRGANOX 1520L); pentaerythriol tetrakis (3-3,5-di-tert-butyl-4-hydroxyphenyl) propionate (IRGANOX 1010); benzenepropanoic acid ester of 3,5-bis (1,1-dimethyl-ethyl) -4-hydroxy-C7-C9 branched alkyl (IRGANOX 1135); 2,6-di-tert-butyl-4- (4,6-bis (octylthio) -1,3,5-triazin-2-ylamino) phenol (BNX ™ 565, Mayzo. Inc); Octadecyl 3- (3,5-di-tert.butyl-4-hydroxyphenyl) propionate (IRGANOX 1076). Examples of amine-type antioxidants are N-isopropyl-N'-phenyl-p-phenylenediamine (IPPD, VULCANOX 4010), N (1,3-dimethyl-butyl) -N'-phenyl-p-phenylenediamine (Antioxidant 4020, 6PPD), N (1,3-dimethyl-phenyl) -N'-phenyl-p-phenylenediamine (7PPD), N-2-ethylhexyl-N'-phenyl-n-phenylenediamine (Novantox 8 PDFA, antioxidant C789), N, N ' -diphenyl-p-phenylenediamine (DFFD), mixed antioxidants of the type Santoflex ™ 134PD, which is a mixture of 1 to 2 products 6PPD and 7PPD.

To isolate rubber modified with silicate from polymerizate or solution, methods of water-steam or anhydrous degassing, known to those skilled in the art, are used. The method of extraction corresponds to the selected technology for obtaining rubber.

The obtained modified rubbers contain 1.0-50.0% wt. layered silicate and can be used in rubber mixtures for the manufacture of rubber goods and tires, in particular the sidewalls of the tire, pressure layer of tires, chamber rubbers, tire tread.

The rubber mixtures of the present invention, which include layered modified layered silicates (clays) rubbers, differ from the known compositions of a similar purpose in that the modified rubber obtained according to the above modification method layered silicate is present in the rubber mixture in the amount of 5-130 wt. h per 100 wt.h rubber or the sum of all rubbers that make up the rubber. When the content in the composition of the rubber is less than 5 wt.h. rubber modified with layered silicates does not provide a sufficient amount of layered silicates in rubber and, as a result, the necessary improvement of rubber properties (for example, gas tightness, hysteresis properties, etc.) is not achieved. Content over 130 wt.h. leads to an increased content of layered silicate in rubber, which negatively affects manufacturability, elasticity, fatigue endurance, strength and other physicomechanical properties of rubber due to a significant decrease in the proportion of polymer in the composite.

Rubber blends or elastomeric compositions in accordance with the present invention may include, in addition to the modified rubbers obtained in accordance with the present invention, other rubbers, as well as various fillers, including clay, and other necessary ingredients known to the art. The composition of rubber mixtures is determined by their purpose and is known to specialists in this field of technology. In one of the preferred embodiments of the invention, the composition of the elastomeric composition may include several rubbers or mixtures thereof.

The clay content in the rubber mixture (Y), which entered into it as part of the modified rubber, can be preferably 1.0-40 to the entire elastomeric part, expressed in mass parts (parts by weight) per 100 parts by weight; more preferably 2.5 to 20, most preferably 3 to 10 wt. h

In accordance with the invention, rubber compounds can be obtained on the basis of:

a) Mixtures of rubbers, preferably two or three, selected from the group of butadiene (A), isoprene (natural or synthetic) (B) and / or styrene butadiene (C), and / or styrene-butadiene-isoprene, and / or butyl rubbers (D) and / or other rubbers. Such mixtures can be used to obtain rubbers of the desired purpose, in particular for the sidewall or tire tread, tire pressure layer, tire tubes, orifice plates for molding vulcanizers. At the same time, one or several rubbers from group (A) and / or (B) and / or (C) and / or (D) and / or other rubbers (N) belonging to any of the specified groups and synthesized in the medium of a hydrocarbon solvent, may contain layered silicates from 1 to 50% wt. In turn, rubbers of group (A) and / or (D) can be modified by the method described in the present invention. In this case, the total content of rubber in rubber (parts by weight per 100 parts by weight of rubber) is determined by the equation:

(A + Y _a ) and / or (B + Y _c ) and / or (C + Y _c ) and / or (D + Y _d ) and / or (N) = 100 + Y ;

Where:

A, B, C, D and N - the content of each of the rubbers (parts by weight per 100 parts by weight of rubber) contained in the rubber mixture individually or in the form of rubber modified with layered silicate;

Y = Y _a + Y _in + Y _с + Y _d is the total clay content (parts by weight per 100 parts by weight of rubber) included in the rubber mixture consisting of one or several rubbers modified with layered silicate: (A + Y _a ), (B + Y _c ), (C + Y _c ) or (D + Y _d ), and other rubbers (N).

b) A mixture of butyl rubbers (D) or polyisobutylene rubbers (E) modified by layered silicates as described in the present invention, with butyl rubbers (D1) or polyisobutylene rubbers (E1) not modified according to the method described in the present invention. In this case, the total content of rubber in rubber (parts by weight per 100 parts by weight of rubber) is determined by the equation:

((D + Y _d ) and / or (E + Y _e )) + (D1 and / or E1) = 100 + Y ;

Where

D, E, D1, E1 - the content of each of the rubbers (parts by weight per 100 parts by weight of rubber) included in the rubber mixture individually or in the form of a composite with a layered silicate;

Y = Y _d and / or Y _e is the clay content (parts by weight per 100 parts by weight of rubber) included in the rubber mixture of one of the composites: (D + Y _d ) and / or (E + Y _e ).

c) One of the modified with layered silicate rubbers obtained from the method described above: butadiene rubber (A), butyl rubber (D), polyisobutylene rubber (E), used to obtain rubbers of the required purpose. In this case, the content of rubber modified in layered silicate in rubber is determined by the equation:

(A or D or E) + Y = 100 + Y;

Where

Y = Y _a or Y _d or Y _e is the clay content (parts by weight per 100 parts by weight of rubber) included in the rubber mixture in the composition of the modified rubber: (A + Y _a ) or (D + Y _d ) or (E + Y _e ).

d) Rubbers and elastomer composites, similarly described in pp. a) b) and c), but containing one or more rubbers, or composites with layered silicate, filled with oil.

The total content of the elastomeric composite consisting of clay modified rubber in the rubber mixture of the present invention can vary in the range from 5 to (100 + X) wt. h. At a dosage of less than 5 wt. h. is not provided necessary to achieve the desired effect of the clay content in the rubber. Dosage (100 + X) wt. h. is the maximum possible amount of the content of the polymer material in the composition of rubber, based on the principles of calculating the composition of rubber.

With the introduction into the composition of rubber mixtures of the composite (s) obtained by the method according to the invention, it is possible to reduce the content of fillers introduced according to the selected recipe at the rubber mixing stage, such as precipitated colloidal silica, fumed silica, carbon black, other fillers (such as, for example, kaolin, calcium carbonate, bentonite, clay, layered silicate) to fully or partially compensate for the amount of layered silicate added to the mixture.

Rubber mixtures according to the present invention may include the following ingredients:

a) fillers: silicon dioxide (colloidal silicic acid); technical carbon, kaolin, calcium carbonate, bentonite, layered silicate;

b) silanizing agents - in case of using highly dispersed precipitated colloidal silicic acid as a filler (a);

c) curing system of agents: sulfur or sulfur donors; vulcanization accelerators selected from sulfenamides, thiurams, thiazoles, guanidines, etc., and their combinations, used to accelerate the process of vulcanization of rubber and obtain the optimal structure of the vulcanization network; vulcanization activators such as metal oxides, amines, etc., among which zinc oxide is the most widely distributed; and:

vulcanizing agents such as alkylphenol-formaldehyde resins, alkylphenolamine resins or peroxides for the vulcanization of butyl rubber, halobutyl rubber, polyisobutylene rubber;

g) technological additives that improve the dispersion of fillers and processability of rubber mixtures;

e) plasticizers and softeners, in particular, selected from the group including: refined products, vegetable oils, synthetic ether resins, products of processing of the coal and coal industry, synthetic oligomeric functionalized and non-functionalized resins;

e) antioxidants / antiozonants / protivotomiteli physical and / or chemical action;

g) other components that ensure the achievement of the required set of technological, vulcanization, physico-mechanical and operational characteristics, including modifiers, for example; fillers, including fibrous, layered, polymeric (such as cross-linked polymeric gels); agents that prevent reversion during vulcanization and increase the heat resistance of rubber; improves stickiness and other properties.

To obtain rubber mixtures according to the present invention, solution-derived (solution) and emulsion polymerization (emulsion), linear, branched, or chemically modified butadiene, isoprene, styrene-butadiene, styrene-butadiene-styrene-isoprene, butyl rubber, and other rubbers.

To obtain rubber compositions according to the present invention may be used natural rubber of various manufacturers, varieties and grades of RSS (Rid Smoked Shits) to IRQPC (International Standards of Quality and Packing of Natural Rubber - International standards and packaging of natural rubber).

The composition of the rubber mixture can also include oil-filled rubber stamps, for example, from the number of emulsion and solution butadiene-styrene or butadiene rubbers, methods for preparing which are disclosed, for example, in US7915349, US6800689, US6602942 (which are included here by reference in their entirety). According to the present invention, carbon black, synthetic amorphous silicon dioxide, mainly precipitated silica filler, both alone and in combination with technical carbon, can be used as main fillers for sidewall, tread, pressure layer, chamber rubber as reinforcing fillers in rubber mixtures.

Used in accordance with the present invention, carbon black may be, for example, carbon black grades N 121, N220, N 330, N 339, N 550, N683, N772, N990 or other brands, individually or as a combination of them, depending on the purpose of rubber and the composition of its formulation.

It is allowed to use two-phase fillers, which are a silica filler with carbon deposited on the surface; and also, the surface of which is impregnated with a combination agent or chemically modified. It is also possible to use silica obtained by the pyrogenic method, for example, products known under the trademark AEROSIL ^® (Evonic Industries AG).

As silica filler (OKN), generally known brands with a specific surface, measured by the BET method, or by the CTAB method, are used in the range of 40-600 m ² / g and dibutyl phthalate adsorption (DBP) in the range of values of 50-400 cm ^3/100 In a preferred embodiment, the silica has a surface area of BET 100-250 m ² / g, a CTAB surface area of 100-250 m ² / g and an oil absorption (DBP) of 150-250 cm ³ / 100g (definition according to GOST 25699.2 -90; EP-A-157.703). As a suitable precipitated silica filler, products of the following brands BS-50, BS-100, BS-120, Zeosil 1165 MP (Rhone-Poulenc SA) can be used; Ultrasil VN2, Ultrasil VN3, Ultrasil 7000 GR and AEROSIL ^® (Evonik Industries AG); Hi-Sil 210, Hi-Sil 190, Hi-Sil 215, Hi-Sil 233, Hi-Sil 255 (PPG Industries Inc.); KS 404, KS 300 and Perkasil 233 (Akzo Nobel); Zeopol 8745, Zeopol 8755 (Huber); Rosil-175 (Soda OJSC) and others.

The amount of silicon dioxide in the elastomeric composition may be 3-100 wt. hours, preferably 5-80 wt. hours, and more preferably 10-95 wt. hours per 100 wt. including elastomeric material. If the content of silicon dioxide is less than 3 wt. h, then this amount may not be enough to achieve the necessary properties of rubber (adhesion, strength, hysteresis characteristics, etc.). On the other hand, when it exceeds 100 wt. h, then deteriorate the workability and mechanical properties under tension.

Rubber blends containing elastomeric composites and filled with silica may contain silanizing agents (combining agents of silicon dioxide and elastomers). The combination agents most commonly used are: bis (3-triethoxysilylpropyl) tetrasulfide, bis (2-triethoxysilylethyl) tetrasulfide, bis (3-trimethoxypropyl) tetrasulfide, bis (2-trimethoxysilylethyl) tetrasulfide, 3-mercaptopropyltrimethoxysilane, I, ai ayi-ay one ay, ayans. -merkaptoetiltrimetoksisilan, 2-mercaptoethyltriethoxysilane, 3-nitropropyltrimethoxysilane, 3-nitropropyltriethoxysilane, 3-chloropropyltrimethoxysilane, 3-chloropropyltriethoxysilane, 2-chloroethyltriethoxysilane, 3-trimethoxysilylpropyl-N, N-dimetiltiokarbamoilt trasulfid, trimethoxysilylpropylbenzothiazoletetrasulfide-3, 3-trietoksisililpropilmetakrilatmonosulfid etc. Of the above components, bis (3-triethoxysilylpropyl) tetrasulfide and 3-trimethoxysilyl propyl benzothiazole tetrasulfide are preferred. In addition, it is possible to use combination agents, which are compositions of the above-mentioned compounds, as well as the above combination agents, deposited on a powdered carrier, for example, carbon black.

It is allowed to use other combination agents designed to improve the compatibility of Windows and rubber, for example, such as NXT and NXT Z 100 (Momentive).

Rubber compounds filled with OKN, as a rule, also contain technological additives that improve the dispersion of fillers and processability of rubber compounds. Examples of such additives can be derived fatty acids (zinc salts and esters, as well as mixtures thereof), known under the trademarks Struktol E44, Struktol GTI and Actiplast ST, which improve the dispersion of fillers and reduce the viscosity of the mixture.

Vulcanization of rubber is carried out using vulcanizing agents known in the art, for example, elemental sulfur, sulfur donors, for example N, N'-dimorpholyl disulfide, polymeric polysulfides, etc. The most widely used in the tire industry is elemental or polymeric sulfur. As is known in the art, the dosage of vulcanizing agents in rubber is typically in the range of 0.5-4.0 wt. hours, sometimes it can reach up to 10 wt. hours at 100 wt.h. rubber Traditionally, such ingredients as vulcanization activators are used together with sulfur, in particular alkaline earth metal oxides and hydroxides (Zn, Mg, Pb, Ca) of metals together with fatty acids; accelerators, in particular sulfenamides, thiazoles, thiurams, guanidines, urea derivatives, etc .; and vulcanization retarders, in particular phthalic anhydride, N-nitrosodiphenylamine, cyclohexylthiophthalimide. Their content depends on the amount of vulcanizing agent and requirements for the vulcanization kinetics and structure of the vulcanization network.

A typical vulcanizing system for rubber structuring based on butyl rubbers, or halobutyl rubbers, or polyisobutylenic rubbers, may be based on peroxide and contains a peroxide vulcanizing agent, such as dicumyl peroxide, di-tert-butyl peroxide, benzoyl peroxide, 2,2'-bis (tert-butyl peroxide) ) -diisopropylbenzene (VulcupR 40KE), benzoyl peroxide, 2,5-dimethyl-2,5-di (tert-butylperoxy) -hexin-3, 2,5-dimethyl-2,5-di (benzoyl peroxy) hexane, 2.5 -bis (tert-butylperoxy) -2,5-dimethylhexane and the like. A preferred peroxide vulcanizing agent containing dicumyl peroxide is commercially available under the trademark DiCup-40C. The peroxide vulcanizing agent, respectively, is used in an amount of from about 0.2 to about 7 parts per 100 parts of rubber, preferably from 1 to 6 parts per 100 parts of rubber, most preferably about 4 parts per 100 parts of rubber. Peroxide vulcanizing coagents may also be used. In this regard, it is mentioned triallyl isocyanurate (TAIC), available for purchase under the DIAK trademark from the DuPont campaign or N, N'-m-phenylenedimaleimide, known as HVA-2 (available from DuPontDow), triallyl cyanurate (TAC) or liquid polybutadiene, known as Ricon D 153 (supplied by Ricon Resins). The amounts of these agents may be equivalent to or less than the amounts of peroxide vulcanizing agents.

Cure system agents for rubbers germosloya, chamber rubbers and diaphragm rubber to shaper-vulcanizates based on butyl rubber, halobutyl rubbers, mixtures thereof with isoprene and / or butadiene rubber may contain a phenol-formaldehyde resin (e.g., sulfur containing alkilfenoloformaldegidnuyu resin - oktofor 105) or alkilfenolaminnye resin ( for example, octofor N), and other resins that are useful as vulcanizing agents in the art.

As plasticizers and softeners in this invention can be used refined products, vegetable oils (eg rapeseed), synthetic essential oils, products of the coal industry, etc., synthetic oligomeric functionalized and non-functionalized products [Rubber Technologist's Handbook, Volume 2, Capert: Rubber Additives - Plasticisers and softeners / JR White, S.K. De, 2001-pp 198-200 (incorporated here by reference in its entirety).

The composition of rubber for tires and rubber, as a rule, includes ingredients for the following purposes: antioxidants, antioxidants, protivootomiteli and other components that ensure the achievement of the necessary technological, vulcanization, physico-mechanical and operational characteristics, for example: modifiers; fillers, including fibrous, layered, polymeric (such as cross-linked polymeric gels), etc .; agents that prevent reversion during vulcanization and increase the heat resistance of rubber; stickiness improvers, etc. The nature of such compounds and their content in rubber depend on the required level of properties of rubber mixtures and vulcanizates and are well known to specialists in this field [see, for example, Pichugin AM, Material science aspects of tire rubber, Koshelev F. F., Kornev A.E., Bukanov A.M. General technology of rubber, Zakharchenko P. I., Yashunskaya F.I., Evstratov V.F., Orlovsky P.N. (Ed. College). Handbook reinschik. Rubber production materials;

https://books.google.ru/books?id=2rxFOm68Ui8C&pg=PA431&lpg=PA431&dq=rubber+technologist's+handbook&source=bl&ots=zN_g2JXB3n&sig=r2ewGaHVFZQoKCJ-6GCakUnedQs&hl=ru&sa=X&ved=0CEcQ6AEwBmoVChMIqpT0s9jxyAIVYr1yCh1zoQ6_#v=onepage&q=rubber%20technologist's%20handbook&f= false (both documents are included here by reference in their entirety)].

Mixtures are prepared by methods known in the art, disclosed, for example, in [Jon S. Dick, Rubber Technology. Compounding and Testing for Performance.Carpet: Mixing (included here by reference in its entirety)], preferably using closed rubber mixers, such as Banbury or Intermix. The mixing process can be carried out in two or three stages, with the second or third stages intended for adding to the mixture the components of the curing group.

The resulting rubber mixtures are characterized by improved technological properties, and the vulcanized mixtures have increased fatigue endurance and are characterized by lower hysteresis losses.

Examples

The invention is confirmed by the following examples of preparation of SKD-butadiene rubber or butyl rubber ND modified bentonite mark "Bentonite" (Bratislava) and / or organoclay Dellite ^® 72T production Laviosa Chimica Mineraria SpA (Italy).

The cold fluidity of rubbers modified according to the invention was determined according to GOST 19920.18-74. Results rubber cold flow evaluation are shown in Tables 1 and 2. In particular, the effect of the dosage organoclay Dellite ^® 72T to cold flow SKD-ND for Examples 1, 4-17 is shown in Table 1. Effect of clay "Bentonite" dosage to cold flow SKD-ND for Examples 1, 18-31 are shown in table 2.

To determine the effect of SKD-ND rubber modified according to the invention on rubber properties, they were tested as part of model rubber for sidewall (recipe given in table 3) and car tire tread (recipe given in table 6), replacing unmodified SKD-ND with specified modified rubbers SKD-ND.

SKD-ND rubber, which is a butadiene rubber and is the product of butadiene polymerization in solution in the presence of rare-earth catalysts containing at least 96% 1,4-cis links, production of JSC Voronezhsintezkauchuk.

In the composition of the rubber also used: synthetic rubber butadiene-styrene DSSK-2560, with a content of 1,2-units of 62-70% wt., Which is a product of polymerization of butadiene-1,3 with styrene in a hydrocarbon solvent in the presence of anionic initiators, produced by JSC " Voronezhsintezkauchuk "; natural rubber brand RSS-1 (SSP.RUBBER (THAILAND) CO., LTD.).

In addition, the following ingredients were used in the rubber composition: carbon black N 339 (Yaroslavl carbon black plant); precipitated colloidal silica Zeosil 1165 MP (Solvay), Si-69 (Evonic) silanizing agent, antioxidant 6PPD (Esatman Santoflex), TMQ antioxidant (Chemtura), Antilux 111 and Antilux 111 protective waxes (RheinChemie), white zinc protective zinc, Antilux 111 and Antilux 111 (RheinChemie), waxes, white zinc, zinc protective antioxidant, Antiqux 111 "), Stearic acid (JSC" Nefis Cosmetics "), technological additive Actiplast ST (RheinChemie), diphenylguanidine (DFG, DFG, RheinChemie), technical ground 9998 (NK LUKOIL), plasticizer Norman 346 (JSC" Orgkhim "), accelerator, accelerator, accelerator Norper 346 TBBS (Vulkacit NZ, Lanxess).

Preparation of rubber mixtures was carried out on the plastic belt Plastograph EC Plus, Model 2008 of the firm “Brabender” (Germany). The free volume of the mixing chamber with cam rotors of type N 50 EHT was 80 cm3. Load factor 0.7. Preparation of rubber mixtures are shown in table 3, was carried out in two stages:

Stage 1 - mixing all ingredients except for the vulcanizing group (ie sulfur, TBBS), the initial temperature of the chamber walls is 60 ° C, the maximum in the chamber during the mixing process is no more than 130 ° C, the rotation speed of the rotors is 40 vol ^-1 ;

Stage 2 - introduction to the rubber mixture of the vulcanizing group (sulfur, TBBS), the initial temperature of the chamber walls is 70 ° C, the maximum is no more than 130 ° C, the rotation speed of the rotors is 40-50 rev ^-1 .

Preparation of rubber mixtures are shown in table 6, was carried out in three stages:

Stage 1 - a mixture of all ingredients except for the vulcanizing group, i.e. sulfur, DFG, TBBS), the initial temperature of the chamber walls is 90 ° C, the maximum in the chamber during mixing is no more than 155 ° C, the rotation speed of the rotors is 40 rpm ^-1 ;

Stage 2 - dispersing the mixture mixture of stage 1 without adding additional ingredients, the initial temperature of the chamber walls is 120 ° C, the maximum is no more than 155 ° C, the rotation speed of the rotors is 60 vol ^-1 ;

Stage 3 - introduction to the rubber mixture of the vulcanizing group, the initial temperature of the chamber walls is 65 ° C, the maximum is no more than 110 ° C, the rotation speed of the rotors is 40 rpm ^-1 .

The vulcanization of rubber obtained according to table 3, was carried out at 155 ° C for 20 minutes The vulcanization of rubber obtained according to table 6, was carried out at 160 ° C for 20 minutes

The fatigue endurance of rubbers listed in Table 3 was evaluated according to GOST 261-79 (amplitude 100%, 250 cycles / min). The test results are presented in table 4.

The hysteresis properties of rubbers (tangent of the angle of mechanical loss tgδ at 60 ° C), obtained according to examples 1,7,21 (table 3) and examples 33,34 (table 6) were determined using an RPA 2000 instrument (Alpha Technologies) according to ASTM D 6601-02 with an amplitude of 10% and a frequency of 10 Hz. The test results are shown in Tables 5 and 7, respectively. The tgδ indicator at 60 ° C describes both the overall level of hysteresis loss in rubber under dynamic operating conditions and the amount of rolling loss in relation to rubber for tire tread.

Molecular mass characteristics of rubbers (Mn, Mw, Mw / Mn) were determined using gel permeation chromatography on an Agilent 1200 f "Agilent Technologies"; the content of 1,4-cis-units - using an Excalibur 3600 f "Varian" IR spectrometer with an ATR attachment; Mooney viscosity according to ASTM ASTM D 1646; characteristic viscosity on the Ubbelod viscometer (solutions of 5.43% in toluene).

Example 1. (comparative)

Obtaining polybutadiene brand SKD-ND is carried out in a hydrocarbon solvent in the presence of a neodymium-containing organometallic complex catalyst according to the method described in patent US 5017539, example 3). The concentration of butadiene in the reaction mass is 10% wt. The dry residue of the reaction mass in the last reactor was 9.68% wt. The conversion of butadiene-1,3 at the time of modification was 97% wt.

The resulting rubber SKD-ND has the following characteristics:

- the content of 1,4-cis-units - 97% wt .;

- molecular weight Mn = 132 * 10 ³ g / mol, Mw = 517 * 10 ³ g / mol;

- polydispersity (Mw / Mn) = 3.92;

- intrinsic viscosity 3.55 dl / g;

- Mooney viscosity is 43 U. MB 1 ÷ 4 (100 ° C);

- cold flow 30 mm / h .

Example 2

Preparation of Dellite Organoclay Suspension ^® 72T in a hydrocarbon solvent Nefras is carried out in a separate apparatus or volumeless mixer before being fed into the polymer, at a temperature of 60 ° C and continuous dispersion of the resulting solution to a homogeneous consistency for 25 minutes. Dellite Suspension Concentration ^® 72T in a hydrocarbon solvent is 10% wt. The resulting suspension is designated as Suspension No. 1.

Example 3

Preparation of Dellite Organoclay Suspension ^® 72T in a hydrocarbon solvent Nefras is carried out in a separate apparatus or volumeless mixer before being fed into the polymer at a temperature of 60 ° C and continuous dispersion of the resulting solution to a homogeneous consistency for 25 minutes. Dellite Suspension Concentration ^® 72T in nefras is 25% wt. The resulting suspension is designated as Suspension No. 2.

Example 4

Modified rubber is obtained according to example 1, with the difference that when the monomer is converted to 97% by weight. a polymer with 9.7% dry residue 10% suspension fed №1 Dellite ^® 72T, prepared according to Example 2. The content of Dellite ^® 72T product obtained is 1% by weight. based on rubber. The suspension modifier serves with constant stirring and a temperature of 60 ° C (± 5). The modification process is 60 minutes. Then the obtained rubber is stopped with softened alkalized water, an antioxidant is added to it and sent at the degassing and drying stages.

Example 5

Modified rubber is obtained analogously to example 4, with the difference that suspension No. 2 in example 3 is used as the modifier suspension.

For rubbers, obtained according to examples 4-5, the value of cold flow decreases by an average of 20% from 30 to 23.9 mm / h (see table 1).

Table 1 - Effect of Dosage organoclay Dellite ^® 72T to cold flow SKD-ND

Indicator Example 1 (sample) Example 4/5 Example 6/7 Example 8/9 Example 10/11 Example 12/13 Example 14/15 Example 16/17 Cold fluidity, mm / h (Δср. In%) 30.0 ( 100 ) 23.8 / 24.0 ( -20.3 ) 13.5 / 14.3 ( -53.6 ) 8.4 / 8.8 ( -71.3 ) 6.0 / 5.4 ( -81 ) 0.5 / 0.7 (-98) 0.4 / 0.2 (-99) ~ 0/0 (-100)

Example 6

Modified rubber is obtained analogously to example 1, with the difference that when the monomer is converted to 97% by weight. a 10% suspension of Dellite ^® 72T prepared according to Example 2 (suspension No. 1) is fed to the polymerizate with a dry residue of 9.7%, at the rate of 6% by weight . Dellite ^® 72T per 100 w.h. rubber The suspension modifier is served with constant stirring and a temperature of 60 ° C (± 5 ° C). The modification process is 60 minutes.

The resulting rubber is stopped with softened alkalized water, an antioxidant is added and sent to the degassing and drying stages.

Example 7

Modified rubber is obtained analogously to example 6, with the difference that suspension No. 2 in example 3 is used as the modifier suspension.

For rubbers, obtained according to examples 6-7, the value of cold flow decreases on average by 54% from 30 to 13.9 mm / h (table 1).

Example 8

Modified rubber is obtained analogously to example 1, with the difference that when the monomer is converted to 97% by weight. in polymerizat at the rate of 10% wt . Dellite ^® 72T rubber is fed 10% suspension of Dellite ^® 72T, prepared according to example 2. The suspension modifier is fed with constant stirring and a temperature of 60 ° C (± 5 ° C). The modification process is 60 minutes. The resulting rubber is stopped with softened alkalized water, an antioxidant is added and sent to the degassing and drying stages.

Example 9

Modified rubber is obtained analogously to example 8, with the difference that suspension No. 2 is used as a modifier suspension.

For elastomeric composites, obtained according to examples 8-9, the value of cold flow decreases on average by 71% from 30 to 8.6 mm / h (table 1).

Example 10

Modified rubber is obtained analogously to example 1, with the difference that when the monomer is converted to 97% by weight. in polymerizat at the rate of 20% wt. Dellite ^® 72T on rubber is fed 10% suspension Dellite ^® 72T, prepared according to example 2 (suspension No. 1). The suspension modifier is served with constant stirring and a temperature of 60 ° C (± 5 ° C). The modification process is 60 minutes. The resulting rubber is stopped with softened alkalized water, an antioxidant is added and sent to the degassing and drying stages.

Example 11

Modified rubber is obtained analogously to example 10, with the difference that suspension No. 2 in example 3 is used as the modifier suspension.

For the modified rubbers, obtained according to examples 10-11, the value of the cold flow decreases by an average of 81.0% from 30 to 5.7 mm / h (Table 1).

Example 12

Modified rubber is obtained analogously to example 1, with the difference that when the monomer is converted to 97% by weight. in polymerizat at the rate of 30% wt . Dellite ^® 72T rubber is fed 10% suspension of Dellite ^® 72T, prepared according to example 2. The suspension modifier is fed with constant stirring and a temperature of 60 ° C (± 5 ° C). The modification process is 60 minutes. The resulting rubber is stopped with softened alkalized water, an antioxidant is added and sent to the degassing and drying stages.

Example 13

Modified rubber is obtained analogously to example 12, with the difference that suspension No. 2 in example 3 is used as the modifier suspension.

For the modified rubbers, obtained according to examples 12-13, the value of the cold flow decreases by an average of 98.0% from 30 to 0.6 mm / h (Table 1)

Example 14

Modified rubber is obtained analogously to example 1, with the difference that when the monomer is converted to 97% by weight. in polymerizat at the rate of 40% wt . Dellite ^® 72T rubber is fed 10% suspension of Dellite ^® 72T, prepared according to example 2. The suspension modifier is fed with constant stirring and a temperature of 60 ° C (± 5 ° C). The modification process is 60 minutes. The resulting rubber is stopped with softened alkalized water, an antioxidant is added and sent to the degassing and drying stages.

Example 15

The modified SKD-ND rubber is prepared analogously to example 14, with the difference that suspension No. 2 of example 3 is used as the modifier suspension.

For the modified rubbers obtained according to examples 14-15, the value of cold flow decreases on average by 99.0% from 30 to 0.3 mm / h (Table 1)

Example 16

Modified rubber is obtained analogously to example 1, with the difference that when the monomer is converted to 97% by weight. in polymerizat at the rate of 50% wt. Dellite ^® 72T rubber is fed 10% suspension Dellite ^® 72T, prepared according to example 2. The suspension modifier is fed with constant stirring and a temperature of 60 ° C (+ -5 ° C). The modification process is 60 minutes. The resulting rubber is stopped with softened alkalized water, an antioxidant is added and sent to the degassing and drying stages.

Example 17

Modified rubber is obtained according to example 10, with the difference that suspension No. 2 in example 3 is used as the modifier suspension.

For the modified rubbers, obtained according to examples 16-17, the value of cold flow decreases by 100% from 30 to 0 mm / h (table 1)

Examples [18-31] rubber modification was carried out analogously to Examples 4-17, with the difference that instead of the organoclay slurry Dellite ^® 72T is used as a modifier to the unmodified clay slurry "Bentonite". Suspensions unmodified clay "Bentonite" organoclay suspensions prepared similarly Dellite ^® 72T according to Examples 2 and 3, respectively. The selection of the final product is carried out by anhydrous degassing of the solvent.

The resulting rubbers according to examples 18-31 are stopped with softened alkalized water, an antioxidant is added and sent to the degassing and drying stages.

For the modified rubbers, obtained according to the conditions in examples 18-31, the effect of the dosage of "Bentonite" on the value of cold flow is shown in Table 2.

Table 2 - The effect of the dosage of clay "Bentonite" on cold flow SKD-ND

Indicator Example 1 (sample) Example 18/19 Example 20/21 Example 22/23 Example 24/25 Example 26/27 Example 28/29 Example 30/31 Cold fluidity, mm / h (Δ in%) 30.0 (100) 29.9 / 29.3 (-1.5) 27.2 / 28.0 (-8.0) 22.1 / 22.7 (-25.0) 18.5 / 18.0
(-39) 12.0 / 12.6 (-59) 6.5 / 5.5 (-80) ~ 0 (-100)

The dependence of cold fluidity of SKD-ND rubber on the content and type of layered silicate is shown in Figure 1. As follows from the presented dependence, with an increase in the content of any of the presented layered silicates in the composition of rubber, its cold flow decreases. When comparing the effect of two grades of layered silicates on the cold flow of ACS-ND, namely Bentonite and Dellite ^® 72, it was found that the use of organomodified Dellite ^® 72 leads to the most significant decrease in the cold flow of rubber.

The rubbers obtained in examples 1, 4-31 were tested in the composition of the model rubber mixture for the sidewall (see table 3). As shown in table 4, rubbers containing bentonite in the amount of 6-50% wt. and Dellite ^® 72 in the amount of 5% wt., provide a significant improvement in the fatigue endurance of these rubber. The hysteresis losses (see table 5) in the represented rubber are also noticeably reduced when they include rubbers modified with layered silicates.

Table 3 - Compositions of rubber compounds for sidewall tires, including rubbers, obtained in examples 1; 4-9; 16-17; 20-25; 32-33

Name of ingredients Content by parts per 100 wt.h. rubber Comparison sample Dellite ^® 72T "Bentonite" Example 1 Example 4-5 Example 6-7 Example 8-9 Example 16-17 Example 20-21 Example 22-23 Example 24-25 Example 32-33 Natural rubber (NC) RSS-1 50 50 50 50 50 50 50 50 50 Butadiene rubber (SKD-ND) 50 ten ten Rubbers, modified layered silicates: SKD-ND 1% Dellite ^® 72T 50.5 SKD-ND 6% Dellite ^® 72T 53.2 ND SKD-10% Dellite ^® 72T 55.5 ND SKD-50% Dellite ^® 72T 80 SKD-ND with 1% Bentonite 50.5 SKD-ND with 6% Bentonite 53.2 SKD-ND with 10% Bentonite 55.5 SKD-ND with 50% Bentonite 80 Filling - TU № 339 50 50 50 50 50 50 50 50 50 Plasticizer - Norman 346 15 15 15 15 15 15 15 15 15 Antioxidant - 6PPD 3.5 3.5 3.5 3.5 3.5 3.5 3.5 3.5 3.5 Antioxidant - Acetonanil N (TMQ) one one one one one one one one one Protective Wax - Anti-Suite 111 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 Activator - White zinc BTSOM 2 2 2 2 2 2 2 2 2 Activator - Stearic Acid 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 Accelerator - Sulfenamide T (TBBS) 1.9 1.9 1.9 1.9 1.9 1.9 1.9 1.9 1.9 Vulcanizing agent - Sulfur ground technical 1.9 1.9 1.9 1.9 1.9 1.9 1.9 1.9 1.9 Total 179.3 179.8 182.5 184.8 219.3 179.8 182.5 184.8 219.3

Table 4 - Effect of Dosage organoclay Dellite ^® 72T and clay "Bentonite" fatigue endurance rubbers

Indicator Sample cipher Counter. sample Dellite ^® 72T "Bentonite" Example 1 Example 4/5 Example 6/7 Example 8/9 Example 16/17 Example 18/19 Example 20/21 Example 22/23 Example 30/31 Fatigue endurance, N thousand cycles 280 237/245 450/444 278/274 229/233 278/281 1692/1690 967/972 789/795

Table 5 - Tangent of the angle of mechanical loss ( tgδ )

Indicator Sample cipher Comparison sample Dellite ^® 72T "Bentonite" Example 1 Example 7 Example 21 RPA 2000 (10%, 10 Hz, offset) tgδ (60 ° C) 0.176 0.133 0.111 Δ for example 1% - -24 -37

Example 32 (reference sample)

Obtaining polybutadiene brand SKD-ND is carried out in a hydrocarbon solvent in the presence of a neodymium-containing organometallic complex catalyst with a concentration of butadiene in the reaction mass of 10% wt. according to example 1, with the difference that the dry residue of the reaction mass in the last reactor was 8.98% wt. The conversion of butadiene-1,3 was 90% wt.

Rubber SKD-ND has the following characteristics:

- the content of 1,4-cis-links - 96% wt .;

- molecular weight Mn = 148 * 10 ³ g / mol, Mw = 465 * 10 ³ g / mol;

- polydispersity (Mw / Mn) = 3.14;

- intrinsic viscosity 3.05 dl / g;

- Mooney viscosity 41 U. MB 1 ÷ 4 (100 ° C);

- cold flow 25 mm / h .

Example 33

Modified rubber is obtained according to example 32, with the difference that in the conversion of monomer 90% wt. in the polymer slurry fed 10% Dellite ^® 72T, prepared according to Example 2 (suspension № 1) at 15% by weight. Dellite ^® 72T on rubber. The suspension modifier serves with constant stirring and a temperature of 60 ° C (± 5 ° C). The modification process is 60 minutes.

Example 34

Modified rubber is obtained according to example 33, with the difference that suspension No. 2 of example 3 is used as the modifier suspension.

Formulations of rubber mixtures based on CWR-2560 and the samples obtained in examples 32-34 are shown in Table 6. As a sample, the rubber mixture based on rubbers PSC-2560 and SKD-ND was used to compare the properties (Example 32).

Table 6. The compositions of the model rubber compounds for the tread of a car tire

Blend components The content of components, wt. hours per 100 wt. rubber rubber Comparison sample
(example 32) Example 33.34 Mortar butadiene-styrene rubber (DSSK-2560) 70.00 70.00 Butadiene rubber (SKD-ND) 30.00 - SKD-ND with 15% wt. Dellite ^® 72T - 30.00 Zeosil 1165 colloidal precipitated silica 80.00 80.00 Silanizing agent Si-69 8.00 8.00 Norman 346 40.00 40.00 Protective wax: Antilux 654 1.50 1.50 Antioxidant6PPD 2.00 2.00 White zinc btsom 3.75 3.75 Stearic acid 2.50 2.50 Diphenylguanidine (DFG) 2.00 2.00 TVBS accelerator 1.70 1.70 Technical sulfur 9998 2.50 2.50

The results of the evaluation of the hysteresis properties of the above rubber, shown in Table 7, show that the SKD-ND rubber modified with layered silicate Dellite ^® 72T reduces the rolling loss (tg δ at 60 ° C ) by 17% compared to the reference sample (rubber containing unmodified SKD-ND).

Table 7 - the tangent of the angle of mechanical losses

Indicator Comparison sample Example No. 33/34 tgδ (60 ° C) 0.089 0.078 / 0.079 Δ DSSK,% -17 / -17

Thus, it can be assumed that the SKD-ND rubber modified by layered silicate is a composite in which part of the polymer chains penetrates into the interlayer space of organic clay, and subsequently, in rubber, this part of the polymer is stored in occluded form. Such microvolumes of SKD-ND rubber do not interact with the main reinforcing filler, forming a phase with low hysteresis and better fatigue characteristics, due to which it can lead to a decrease in hysteresis loss and an increase in fatigue endurance of rubber in general.

Example 35. Preparation of a 15% suspension of organoclay Dellite ^® 72T in a mixture of isopentane (36 wt.%) And chloroethane (64% wt.). Isopentane and chloroethane were specially prepared according to the requirements for solvents used in the synthesis of butyl rubbers or polyisobutylene rubbers. The preparation of the suspension was carried out immediately before feeding into the polymer at a temperature of minus 45 ° C, either in a separate apparatus with continuous stirring for 25 minutes, or in a volume-free mixer.

Example 36 (comparative). Getting butyl rubber. Butyl rubber (BC) is obtained according to the conditions described in patent RU 2259376 (examples 1 and 4, para. 15 and 35 on page 4): the reactor is charged with the charge based on 70% of the load of the reactor by volume, containing (wt.%) isobutylene - 42.7, isoprene - 1.3, chloroethane - 35.0, isopentane - 21.0, and the initiator of ethyl aluminum sesquichloride (EASX) in isopentane (concentration of 8 g / l) with a total content of protonated complexes of 45% at the rate of 2, 26 l of initiator solution per 1 ton of charge. The process is conducted at -45 ° C. The polymerization is stopped by methods known in the art, for example by the addition of isopropyl alcohol. The resulting polymer has a solids content of 15% and a monomer conversion of 35%. The rubber is characterized by a Mooney viscosity of 50 units. and cold flow - 20 mm / h.

Example 37. Getting butyl rubber, modified layered silicate. Butyl rubber (BR) is prepared according to the conditions described in Example 36, except that the resulting polymer with a dry residue content of not less than 13% and the monomer conversion 33% (that is 95% of the target conversion) is fed slurry organoclays Dellite ^® 72T, obtained according to example 35, at the rate of 5% wt. clay on rubber in polymerizate. Then the process continues until the target conversion of 35% is achieved. The polymerization is stopped by methods known in the art, for example by the addition of isopropyl alcohol. The rubber thus obtained is characterized by a Mooney viscosity of 45 units. and cold flow 10 mm / h.

As follows from the above data (Tables 1, 2, Fig. 1 and Example 37), physical modification at the final stage of polymerization of rubbers with layered silicates provides a controlled decrease in their cold flow.

In addition, the use of SKD-ND rubber physically modified with layered silicates helps to reduce hysteresis losses and increase fatigue endurance of rubbers, in particular rubbers for a tire sidewall, as shown in Tables 3.4 and 5.

The positive effect of SKD-ND rubber filled at the polymerization stage with layered silicate on the hysteresis properties of the tread rubber was also noted (see Table 7).

The positive effect of layered silicates on the gas impermeability of rubbers based on butyl, halobutyl or polyisobutylene rubbers does not require additional confirmation, since this effect is well known in the art and has been widely described in the literature.

The above description and examples are intended only for purposes of explanation and illustration of the present invention and cannot be considered as limiting its scope. The real nature and scope of the present invention for which legal protection is sought is defined by the following claims.

Claims (18)

1. A method of producing rubber with low cold flow, where the rubbers are selected from the group including polybutadiene rubber, butyl rubber, polyisobutylene rubber, including: introducing a suspension of layered silicate into a polymer that is formed during the polymerization process during the production of rubber, followed by stabilization, degassing, separation, separation, and subsequent degassing of the laminated silicate. the product obtained, characterized in that the silicate is introduced in the form of a suspension into the polymer while achieving a monomer conversion of not less than (0.95 ÷ 1.0) * X%, where X is the target conversion for yes Nogo polymerization process. 2. The method according to claim 1, characterized in that the resulting rubber is a 1,4-cis-butadiene rubber, and wherein X is 95-100%, preferably 99-100%. 3. The method according to claim 1, characterized in that the resulting rubber is butyl rubber or polyisobutylene rubber, and wherein X is 5-100%, preferably 10-80%, more preferably 20-40%. 4. The method according to claim 1, characterized in that the polymerizate is obtained by (co) polymerizing the monomer (s) in solution in the presence of a polymerization initiator. 5. The method according to claim 1, wherein the layered silicate is selected from the group consisting of montmorillonite clays, kaolinite clays, chlorite clays, hydromicas and mixed-layer minerals. 6. The method according to claim 1, characterized in that an aliphatic, alicyclic, aromatic hydrocarbon, chlorinated hydrocarbon, and / or mixtures thereof, and / or part of the resulting polymerizate is used as the dispersion medium of the suspension of the layered silicate. 7. The method according to claim 1, characterized in that the layered silicate is a modified layered silicate, and an aliphatic, alicyclic, aromatic, chlorinated hydrocarbon and / or mixtures thereof, and / or part of the resulting polymerizate are used as the dispersion medium of the suspension. 8. The method according to p. 6 or 7, characterized in that the aliphatic hydrocarbon is selected from the group including pentane, isopentane, hexane, heptane, octane, isooctane, hexane-heptane fraction of hydrocarbons with different ratios of hexane to heptane; and / or an alicyclic hydrocarbon selected from the group including cyclopentane, cyclohexane, methylcyclohexane, cycloheptane; and / or the aromatic hydrocarbon is selected from the group comprising benzene, toluene, xylenes, ethylbenzene, diethylbenzene, isobutylbenzene, isopropylbenzene; and / or a chlorinated hydrocarbon is selected from the group comprising chloromethane, dichloromethane, chloroethane, chloromethylene. 9. The method according to claim 1, characterized in that the silicate suspension is prepared by dispersing the silicate in a dispersion medium at a temperature of from -90 to + 100 ° C by vigorous stirring over a period of time of 10-90 minutes. 10. The method according to claim 1, characterized in that the layered silicate is introduced into the polymer in the form of a suspension in a solvent in the amount of 1.0-50% wt. on the amount of rubber contained in the polymerizate. 11. The method according to claim 1, characterized in that the silicate is introduced into the polymerizate in the form of a suspension in a polymerizate with a silicate concentration of 5-180% by weight. in the calculation of the rubber, which is part of the polymerizate forming the dispersion medium of the specified silicate suspension. 12. The method according to claim 1, characterized in that the silicate is introduced into the polymerizate as a suspension in a rubber solution with a silicate concentration of 5-180% by weight. in the calculation of the rubber, which is part of the solution of rubber. 13. The method according to any of paragraphs.6-12, characterized in that the antioxidant is additionally added to the suspension of silicate in the selected medium in an amount of 0.2-3.0% wt. on the mass of rubber contained in the polymerizate, preferably from 0.3-1.5% by weight, more preferably from 0.2-0.4% by weight. 14. The method according to claim 1, characterized in that the amount of silicate in the modified rubber is from 1 to 50% wt. 15. Modified rubber with low cold flow, obtained by the method according to any one of claims 1 to 14. 16. Rubber mixture for the manufacture of products containing one or more modified rubbers in clause 15. 17. The rubber mixture according to claim 16, where the product is an element of a tire selected from a tire sidewall, a tire tread, a tire pressure layer and a tire chamber containing one or more modified rubbers obtained by the method according to any one of claims 1 to 14. 18. The product is made of a rubber mixture according to any one of paragraphs.16, 17.

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