Technical field

5 The invention relates to the field of production of synthetic rubbers, in particular diene rubbers, such as polybutadiene , polyisoprene and styrene-butadiene rubber (SBR) , and styrene-isoprene-butadiene rubber (SIBR) , which can be used in the production of tires and rubber technical

10 goods, modification of bitumen, in the electrical engineering and other fields. In particular, the invention relates to an anionic (co) polymerization initiator containing functional groups, and a method for preparing thereof, as well as to a method for preparing

15 functionalized diene (co) polymers by using said initiator.

Background

Performance characteristics of rubbers, such as rolling resistance, road grip and the like, depend on both properties of a rubber and how the rubber interacts with

20 and to what extent it is compatible with a silica filler.

An increase in thermodynamic affinity of a rubber for silica fillers promotes a reduction in energy consumption during mixing these components and a significant improvement of basic properties of the rubber. Silica

25 fillers contribute to an increase in rolling resistance, road grip, while reducing hydroplaning risk. A main drawback of silica fillers is in their poor thermodynamic affinity for general-purpose rubbers, which, in turn, affects physicochemical properties of the vulcanizates

30 (rubbers) prepared by using thereof.

An improvement of thermodynamic affinity of a rubber for silica fillers is achieved through modification of the rubber with polar groups. In the art it is known that the existence of functional groups, for example, tin-, silicon- or nitrogen-containing groups in a rubber allows an improved distribution of reinforcing fillers in the rubber matrix, which, in turn, provides a decrease in hysteresis losses and an improvement of wear resistance and wet grip properties of rubber-based vulcanizates.

Modification of a rubber with polar groups is possible in several ways :

- use of functionalizing agents (such as Michler's ketone, N-methylpyrrolidone , etc.), i.e. compounds capable of being incorporated into the macromolecules of an obtained rubber, the compounds having a heteroatom- containing functional group. The functionalizing agents are typically introduced into a rubber polymerizate at 95-100% conversion of initial monomers to ensure chain-end- functionalization of the macromolecules of the rubber;

use of monolithium, dilithium and multilithium initiators containing functional groups;

- a combined method (use of an organolithium initiator containing functional groups, followed by a reaction between living rubber chains and functionalizing agents) ; and

- use of functional group-containing monomers (such as aminostyrene and the like) , i.e. compounds capable of entering into a polymerization process (i.e. capable of being incorporated into the macromolecule of an obtained rubber) , which compounds comprise a heteroatom-containing functional group. The functional group-containing monomers are generally introduced into a polymerization system either together with initial monomers or up to 50% conversion of initial monomers to ensure functionalization of the macromolecules of a rubber along the chains (in- chain- functionalization) , or at 95-100% conversion of initial monomers to ensure, just as for the use of a functionalizing agent, functionalization of the ends of the rubber macromolecules (end-chain- functionalization) [1. V. R.-S. Quiteria C.A. Sierra , J. M. Gomez-Fatou, C. Galan , L.M. Fraga. Tin-coupled styrene-butadiene rubbers

(SBRs) . Relationship between coupling type and properties //Macromolecular Materials and Engineering, 1999. - 246. - 2025-2032 p. 2. C.A. Uraneck, J.N. Short. Solution- polymerized rubbers with superior breakdown properties //J. Appl.Polym. Sci, 2003. - 14. - 1421-1432 p. 3. Takashi Ishizone, Akira Hirao, Seiichi Nakahama . Anionic polymerization of monomers containing functional groups. 2. Anionic living polymerization of 4 -cyanostyrene //Macromolecules, 1991. - No.24. - pp. 625-626 4. Takashi Ishizone, Nobuyuki Sueyasu, Kenj i Sugiyama, Akira Hirao, and Seiichi Nakahama. Anionic polymerization of monomers containing functional groups. 7. Anionic polymerizations of N-alkyl-N- (4 -vinylbenzylidene) amines //Macromolecules, 1993. - No.26. - pp. 6976-6984 5. Takashi Ishizone, Yukiko Okazawa, Kenj i Ohnuma, Akira Hirao, and Seiichi Nakahama.

Anionic polymerization of monomers containing functional groups. 8. Anionic living polymerization of 4-cyano-ot- methylstyrene //Macromolecules, 1997. - No.30. - pp.757- 763] .

A method for preparing diene (co) polymers containing functional groups known in the art (RU 2175330 CI) comprises ( co) polymerization of corresponding monomers in a hydrocarbon solvent in the presence of a nitrogen- containing organolithium initiator, wherein the nitrogen- containing organolithium initiator is a product of a reaction between dimethylamine or diethylamine and alkyllithium in a molar ratio of alkylamine : alkyllithium of (1.0-1.5) : 1.0. During formation of said initiator, methyl tert-butyl ether is further added to the polymerization medium in a molar ratio of said ether to alkyllithium of (0.5-3.0) : 1.0. At the end of the polymerization process, a coupling agent (in particular, tetraethoxysilane) can be further added. At the end of the coupling step, lithium ethylenediamine can be added to the solution.

A disadvantage of this initiator is a low polymerization rate since the reaction between alkylamines with alkyllithium results in the formation of amide lithium whose N-Li bond has a lower activity, for which reason it is necessary to increase the rate of the (co) polymerization reaction, which is economically unprofitable.

US 5959048 discloses a method for preparing an amino- containing organolithium initiator which is a mixture of 90-10 weight parts of aminolithium of formula AiLi and 10- 90 weight parts of aminolithium of formula A ₂ Li, wherein Αχ and A ₂ are different and independently selected from the group of: dialkyl-, alkyl-, cycloalkyl- and dicycloalkyl

amine radical of formula and cyclic amine radicals of formula , wherein each Rl is independently selected from the group of alkyls, cycloalkyls and aryls, each of which comprises from 3 to 12 carbon atoms, R2 is selected from the group of alkylene, oxy- and aminoalkylene , each of which comprises from 3 to 16 methylene groups (for example, a mixture of lithium trimethyl hexamethyleneamide and lithium 3,3,5- trimethyltetrahydroazepine) .

The initiator is prepared by a reaction of n- butyllithium with a mixture of branched amines of the above-mentioned structure in an aliphatic solvent. Electron donor additives used in this method are tetrahydrofuran, 2 , 2 ' -ditetrahydrofurylpropane , dipiperidinethane , dimethyl ether, diethyl ether, tributylamine , tetramethylethylenediamine (TMEDA) , ethylene glycol ethers, and "crown" ethers. The resulting polymer is vulcanized to produce a vulcanizate with reduced hysteresis losses, reduced rolling resistance and reduced heat build-up.

Disadvantages of this method include:

1) a need for use of two different amines to produce a storage stable solution of an initiator; when only one of the amines is used to prepare the initiator, the latter precipitates almost immediately;

2) the process for preparing, the initiator lasts more than 12 hours;

3) storage of soluble lithium amides for more than 30 days leads to the precipitation of the nitrogen-containing initiator from the solution, which makes it impossible to provide a given amount of the initiator in the polymerization process.

The object of the present invention is to develop an effective method for preparing functionalized diene (copolymers characterized by a random distribution of their monomer units, a high content of vinyl units, such as 1,2- butadiene and/or 3,4-isoprene units (more than 50%), and a narrow molecular weight distribution (1.4-1.7).

In particular, the object of the present invention is to develop an anionic polymerization initiator characterized by a high long-term (more than 30 days) storage stability, an ability to reduce the time of polymerization (increase a polymerization rate) by 10-20%, while providing production of vulcanizates from the functionalized diene (co-) polymer rubbers having desired, in some cases improved combination of physico-mechanical and elastic-hysteresis properties, wherein the rubbers are characterized by a random distribution of their monomer units, a high content of vinyl units (1, 2 -butadiene and/or 3,4-isoprene units (more than 50%) , and a narrow molecular weight distribution (1.4-1.7) . Thus, for example, the use of said initiator allows an improvement of rolling resistance by 10-20%, wet grip by 5-10% and wear-resistance by 5-10%.

Summary of the invention

The object is solved and a desirable technical result is achieved by the present invention according to which a rubber is prepared in a hydrocarbon solvent in the presence of an initiator being a product or a mixture of products of interaction between an amino alcohol and an organolithium compound or an alkali metal. Said amino alcohol is a mixture of products prepared by a reaction of amine, in particular aniline, with epoxyalkane , wherein said products can be represented by general formula

wherein R _x and R ₂ are independently selected from the group including H-, a linear, branched or cyclic (Ci- Cio)alkyl group, and -Ar;

R ₃ is selected from the group including H-, a linear, branched or cyclic (Ci-Ci ₀ ) alkyl group, and -Ar;

R ₄ is independently selected from the group including a linear, branched or cyclic (Ci-Cio) alkyl group and -Ar group . Said initiator can be prepared either preliminarily by a reaction of an amino alcohol with alkali metals or organolithium compounds, or in situ (directly in a polymerization reactor) by a reaction of the amino alcohol with organolithium compounds. Furthermore, the reaction of the amino alcohol with alkali metals or organolithium compounds is conducted in a hydrocarbon solvent.

The present invention also relates to a process for preparing functionalized diene (co- ) polymers by polymerization of dienes or their copolymerization with each other and/or with alpha-olefins in a hydrocarbon solvent in the presence of an anionic (co- ) polymerization initiator and an electron-donor additive, wherein said anionic ( co- ) polymerization initiator is the aforesaid initiator being a product or a mixture of products of reacting an amino alcohol with organolithium compounds or alkali metals.

Detailed description of the invention The present invention relates to a method for preparing an anionic (co) polymerization initiator containing functional groups, by a reaction of an amino alcohol with an alkali metal or an organolithium compound in a hydrocarbon solvent .

The organolithium compound used in the claimed method is alkyllithium, preferably C ₄ -C ₆ -alkyllithium, more preferably n-butyllithium, sec-butyllithium, tert- butyllithium, or isopropyllithium .

The alkali metal used herein is preferably sodium or potassium .

Examples of the amino alcohols that can form said products are 1- (phenylamino) hexan- 2 -ol, 1,1'-

(phenylazanidyl) dihexan-2 -ol , and 2 - (phenylamino) hexan-1- ol. A molar ratio of the organolithium compound or the alkali metal to the amino alcohol is usually (3÷20):1, preferably (3÷15) :1, more preferably (3÷10) :1.

The amino alcohol is prepared by a reaction of epoxyalkane with a primary or a secondary amines, in particular aniline, under boiling in a mixture with each other for about from 15 to 30 hours, preferably from 20 to 25 hours.

The primary amines used herein are e.g. compounds selected from the group including methylamine, ethylamine, aniline and the like. The secondary amines used herein are e.g. compounds selected from the group including piperidine, dimethylamine, diethylamine , pyrrolidine and the like.

The epoxyalkanes used herein are compounds selected from C ₂ - Cio -epoxyalkanes , preferably selected from C ₄ - C ₉ - epoxyalkanes , for example, epoxybutane (butene oxide), epoxypropane (propylene oxide) , epoxyhexane (hexene oxide) , epoxyoctane (octene oxide) and the like.

The epoxyalkanes according to the present invention are typically prepared by oxidation of corresponding alkenes with peroxide compounds by catalytic or non- catalytic methods in a solution of polar solvents. The oxidation usually lasts for from 5 to 24 hours at the temperature of from 0 to 50 °C. At the end of the synthesis, the solution is treated with an aqueous alkaline solution (2-5%) to decompose unreacted peroxide compounds and neutralize acid sites. An organic layer is treated with a 5% sodium or potassium hydrocarbonate solution, then is washed with water and dried under anhydrous sodium sulfate. Epoxide is separated from the solution by distillation. The purity of the epoxide is about 98.5%. The polar solvent used herein is a compound selected from the group of tetrahydrofuran (THF) , triethylamine , etc. The oxidation, distillation, and drying processes are conducted by known, conventional methods, for example, as disclosed in details in US 5684170 and RU 2180661 (see examples 1-6) .

According to the first method (preliminary preparation) , the initiator is synthesized in a hydrocarbon solvent, for example, in nefras (hexane- heptane fraction) , hexane, heptane, cyclohexane, and the like, by reaction of an alkali metal or an organolithium compound with an amino alcohol.

The reaction is preferably conducted at the temperature of from 0 to 100 °C, more preferably from 15 to 85°C, and even more preferably from 20 to 50°C. The time of reaction is usually from 10 to 600 minutes, preferably from 60 to 120 minutes.

According to the second method {in situ) , the initiator is synthesized in a hydrocarbon solvent directly in a polymerization reactor, for example, in nefras (hexane -heptane fraction) , hexane, heptane, cyclohexane, and the like, by addition of the initiator components (an amino alcohol and alkyllithium) to a butadiene -styrene batch preferably at the temperature from 0 to 30 °C, and more from 10 to 20 °C. The reaction is preferably conducted at temperature of from 10 to 80 °C, more preferably from 15 to 45°C, and even more preferably from 20 to 35 °C. The time of reaction is usually from 30 to 120 minutes, preferably from 40 to 90 minutes, and even more preferably from 50 to 80 minutes.

The anionic (co- ) olymerization initiator having functional groups, prepared as disclosed above, can be used for the production of functionalized diene polymers and copolymers .

The dienes used herein are preferably conjugated dienes, in particular, C4-C12 dienes, for example, such as butadiene, isoprene, piperylene, 2 , 3 -dimethyl- 1 , 3 - butadiene, 2 -methyl-3-ethyl-l, 3 -butadiene, 3 -methyl- 1 , 3 - pentadiene, 2 -methyl- 3 -ethyl- 1, 3 -pentadiene , 3 -methyl -1, 3- pentadiene, 1 , 3 -hexadiene , 2 -methyl- 1, 3-hexadiene, 1,3- heptadiene, 1 , 3 -butadiene, 3 -methyl- 1 , 3 -heptadiene , 1,3- octadiene, 3 -butyl- 1 , 3 -octadiene , 3 , 4 -dimethyl- 1 , 3 - hexadiene, 3 -propyl- 1 , 3 -butadiene , 4 , 5 -diethyl -1 , 3 - octadiene, 2, 3-diethyl-l, 3-butadiene, 2 -methyl- 3 - isopropyl- 1 , 3 -butadiene , or a mixture thereof. The alpha-olefin used herein can be a compound selected from the group including alpha-olefins , preferably, from C8-C40 arylvinyl compounds, in particular, selected from the group including vinylbenzenes , in particular, styrene and alpha- methylstyrene ; vinylbiphenyls , in particular, vinyldiphenyl ; vinylnaphthalenes , in particular, 1- vinylnaphthalene and 1 -methyl -vinylnaphthalene ; and vinylanthracenes , in particular, 9 -vinylanthracene .

The polymerization of dienes or their copolymerization with each other and/or with alpha-olefins is conducted in an hydrocarbon solvent in the presence of an anionic (co- polymerization initiator and an electron-donor additive.

As the anionic (co) polymerization initiator, the above-described initiator having functional groups is used, which is prepared by a reaction of an amino alcohol with organolithium compounds or alkali metals, wherein the reaction is performed either previously or in situ (directly in a polymerization reactor), as disclosed above.

As the electron-donor additive used herein is a compound comprising at least one heteroatom selected from oxygen, nitrogen and phosphorus, more preferably from oxygen and nitrogen. Examples of the electron-donor additive can be compounds represented by one or more of the following formu]

wherein n is from 1 to 20; R and R' are CH ₃ , C ₂ H ₅ , n- C ₃ H ₇₇ 1-C ₃ H ₇ , n-C ₄ H ₉ , s-C ₄ H ₉ , t-C ₄ H ₉ 1-C ₄ H ₉ , C ₅ H , CgHi ₃ , CyHis, C ₈ H ₁₇ , C ₉ H ₁₉ , C ₁₀ H ₂₁ , C ₆ H ₅ , o-C ₆ H ₄ CH _3i m-C ₆ H ₄ CH ₃ , p-C ₆ H ₄ CH ₃ , o- CgH ₄ C ₂ H ₅ , ffl- 0 _¾ Η ₄ C ₂ H ₅ , or ^5-CgH ₄ C ₂ H ₅ .

Compounds such as Ν,Ν,Ν',Ν'- tetramethylethylenediamine , trimethylamine , ethylene glycol ethyl- tert-butyl ether, (di-tetrahydrofuryl) ropane, ethylene glycol di- tert-butyl ether, or a mixture thereof are preferably used as the electron-donor additive.

A molar ratio of the organolithium compound or the alkali metal-containing anionic (co- ) olymerization initiator to the compound comprising at least one heteroatom is generally 1 : (0.1÷20.0) . Said ranges of the molar ratio are determined by the need to obtain a given amount of vinyl groups (not more than 50 wt.%) in the butadiene part of a polymer chain, control the degree of statistical distribution (micro-blockiness ) of alpha- olefins in a rubber, for example, styrene or derivatives thereof if they are used as comonomers of diene.

Hydrocarbon solvents suitable to be used for the polymerization are, for example, nefras (hexane-heptane fraction) , hexane, heptane, cyclohexane, etc. Nefras is most preferable as a solvent.

The process of (co- ) polymerization is preferably conducted at the temperature of from 30 to 80 °C. After synthesis, the catalyst is deactivated, and the rubber is stabilized by addition of a solution of an antioxidant, for example, agidol-2, Irganox 1520L or other known antioxidants, to the polymerizate in an amount of 0.2 to 0.6%. Then, the rubber is isolated by known methods, such as water- steam degassing and drying on rollers.

The properties of the prepared rubber can be additionally improved by additional functionalization . Such additional functionalization is carried out after achieving 95-100% conversion of the initial monomers by addition of functionalizing agents. In the other embodiment of the invention, the additional functionalization is carried out by addition functional group-containing monomers to the polymerization system, which are added simultaneously with the initial monomers or during the polymerization reaction up to 50% conversion of the initial monomers, and, in some cases, at 95-100% conversion of the initial monomers. The functionalizing agents are used to achieve end-chain functionalization of the rubber macromolecules , and the functional group-containing monomers are used to achieve in-chain and, in some cases, end-chain f nctionalization of the rubber macromolecules. As the functionalizing agents used herein, compounds may be used selected from the group consisting of: N, -disubstituted aminoalkylacrylamides and N, -disubstituted aminoalkylmethacrylamides , in particular, N, N-dimethylaminopropyl acrylamide and N,N- dimethylaminopropyl methacrylamide ; N- substituted cyclic amides, such as N-methyl-2 -pyrrolidon, N-vinyl-2- pyrollidon, N-phenyl-2-pyrrolidon, N-methyl -epsilon- caprolactam; N-substituted cyclic ureas, such as 1,3- dimethylethylene urea and 1, 3-diethyl-2-imidazolidinone; and N-substituted aminoketones , for example, such as N,N- bis (dimethylamino) benzophenone (Michler's ketone), Ν,Ν'- bis (diethylamino) benzophenone , or mixtures thereof. A molar ratio of the functionalizing agent to the anionic (co) polymerization initiator is from 0.01 to 2.0, preferably from 0.1 to 1.0.

As the functional group-containing monomer used herein, compounds may be used selected from the group including a silicon-containing compound, a phosphorus- containing compound, a silicon-nitrogen-containing compound, a nitrogen-containing compound, a tin-containing compound, in particular such as 2-dimethylaminopropyl-l, 3- butadiene, 2-triethylsilylpropyl-l, 3-butadiene or dimethylaminomethyl styrene, trimethylsilylstyrene , Ν,Ν'- bis ( trimethylsilyl ) aminomethyl styrene, 4 -diphenylphosphine styrene, 4 -triphenyltin styrene, N, -dimethylaminoethyl styrene, N, N-diethylaminoethyl styrene, or mixtures thereof. The functional group-containing monomer is added in an amount of from 0.01 to 30.0% by weight based on the polymer. Functionalization is generally conducted at the temperature of from 30 to 100°C, preferably from 60 to 80°C, for from 15 to 60 minutes.

The use of the claimed method allows the preparation of functionalized diene (co- ) polymers having random distribution of monomer units, narrow molecular weight distribution (MMD) and a high content of vinyl units (1,2- butadiene and/or 3,4-isoprene units) of more than 50%, as well as an improved combination of properties, in particular, physico-mechanical and elastic-hysteresis characteristics .

Examples of invention embodiment Example 1

1 mole of epoxyhexane- 1 , 2 was dropped to 1 mole of aniline for 1 hour at the boiling temperature of the solution (between 120 and 130°C) . Further, the reaction mass was boiled for 15 hours. The solution became viscous and brown in color. Then the solution was cooled, and unreacted reactants and by-products were distilled. The viscosity of the solution increased.

The resulting mixture was treated with n-butyllithium at a ratio of 3 equivalents of n-butyllithium (1.6 M solution in hexane) to one equivalent of the resulting mixture (amino alcohol) . The concentration of active lithium (0.2 M) was determined by a standard method.

A I L glass reactor equipped with temperature and pressure sensors, a loading unit and a discharger, a mixer, and a jacket was loaded with a batch consisting of 350 g of nefras previously dried and deoxygenated, 46 g of butadiene, and 12 g of styrene (in a weight ratio of monomers in the reaction medium of 79:21). The temperature of delivering to the reactor was -10 °C. When the temperature in the reactor reached 15 °C, a catalytic system consisting of a monolithium initiator prepared as disclosed above and an electron-donor additive was added thereto. The electron-donor additive included ditetrahydrofurylpropane (DTHFP) as a 0.089 M solution in nefras, based on a ratio of DTHFP: lithium of 0.6 mol/mol. The monolithium initiator was fed to the reactor in the form of a 0.20 M solution in nefras in an amount of 1.8 mol of the initiator per 100 g of monomers. The process of copolymerization was conducted at 55°C to 100% conversion. When the conversion was completed, an antioxidant was added. The antioxidant was agidol-2 in an amount of 0.5 wt.%.

The resulting product had the following characteristics: the amount of styrene is 21 wt.%; the amount of 1 , 2 -butadiene units per polybutadiene is 62 wt.%; glass-transition point is 25°C; Mn = 146,000; polydispersity is 1.5; and Mooney viscosity equals to 50 units .

Physico-mechanical and elastic-hysteresis properties of vulcanizate based on the rubber prepared according to Example 1 are given in Table 1.

Example 2

One mole of epoxyhexane-1 , 2 was added by drops to one mole of aniline for 1 hour at the solution boiling temperature of between 120 and 125°C. Further, the reaction mass was boiled for 30 hours. The solution became sticky and brown in color. Then the solution was cooled, and unreacted reactants and by-products were distilled. The viscosity of the solution increased.

The resulting mixture was treated with n-butyllithium in a ratio of 3 equivalents of n-butyllithium (1.6 M solution in hexane) to one equivalent of the resulting mixture (amino alcohol) in hexane at temperature of 20°C. The concentration of active lithium (0.30 M) was determined by a standard method.

A I L glass reactor equipped with temperature and pressure sensors, a loading unit and a discharger, a mixer, and a jacket was loaded with a batch consisting of 350 g of nefras previously dried and deoxygenated, 46 g of butadiene, and 12 g of styrene (in a weight ratio of monomers in the reaction medium of 79:21). The temperature of delivering the batch to the reactor was minus 10°C. When the temperature in the reactor reached 15 °C, a catalytic system consisting of a monolithium initiator prepared as disclosed above and an electron-donor additive was added thereto. The electron-donor additive included tetramethylenediamine in the form of a 0.065 M solution in nefras, based on a ratio of TMEDA: lithium of 1.0 mol . The monolithium initiator was fed to the reactor in the form of a 0.30 M solution in nefras in an amount of 2.0 mol of the initiator per 100 g of monomers. The process of copolymerization was conducted at 50°C. When the conversion reached 95-100%, a functionalizing agent being N-vinyl-2- pyrrolidone was added in the form of a 0.038 M solution in a molar ratio to Li of 0.01; the reaction was continued for additional 30 minutes at temperature of 60 °C. The antioxidant used herein was agidol-2 in an amount of 0.5 wt . % .

The resulting product had the following characteristics: the amount of styrene is 21 wt . % ; the amount of 1 , 2 -butadiene units per polybutadiene is 64 wt.%; glass- transition point is-23°C; Mn = 140,000; polydispersity is 1.42; and Mooney viscosity equals to 48 units .

Physico-mechanical and elastic-hysteresis properties of vulcanizate based on the rubber prepared according to Example 2 are given in Table 1.

Example 3

One mole of epoxyoctane- 1 , 2 was added by drops to one mol aniline for 1 hour at the boiling temperature of the solution of 160°C. Further, the reaction mass was boiled for 20 hours. The solution became sticky and brown in color. Then the solution was cooled and unreacted reactants and by-products were distilled. The viscosity of the solution increased.

The resulting mixture was treated with sec- butyllithium in a ratio of 20 equivalents of sec- butyllithium (1 M solution in hexane) to one equivalent of the resulting mixture (amino alcohol) in nefras at room temperature. The concentration of active lithium (0.25 M) was determined by a standard method.

A I L glass reactor equipped with temperature and pressure sensors, a loading unit and a discharger, a mixer, and a jacket was loaded with a batch consisting of 350 g of nefras previously dried and deoxygenated, 46 g of butadiene, 12 g of isoprene, and 8 g of styrene. The temperature of delivering the batch to the reactor was minus 10 °C. When the temperature in the reactor reached 15 °C, a catalytic system consisting of a monolithium initiator prepared as disclosed above and an electron-donor additive was added thereto. The electron-donor additive included ditetrahydrofurylpropane (DTHFP) in the form of a 0.070 M solution in nefras, based on a ratio of DTHFP : lithium of 0.1 mol . The monolithium initiator was fed to the reactor in the form of a 0.25 M solution in nefras in an amount of 1.5 mol of the initiator per 100 g of monomers. The process of copolymerization . was conducted at 55°C to 100% conversion. When the conversion was complete, an antioxidant was added. The antioxidant used herein was agidol-2 taken in an amount of 0.5 wt . % .

The resulting product had the following characteristics: the amount of styrene - 14 wt.%; the amount of 1 , 2 -butadiene units per polybutadiene - 45 wt.%; the amount of 3, 4 -isoprene units per polyisoprene - 55%; glass-transition point is-21°C; Mn = 178,000; polydispersity is 1.7; and Mooney viscosity equals to 64 units .

Example 4

One mole of poxybutane-1 , 2 was added by drops to one mole of aniline for 1 hour at the boiling temperature of the solution (65°C) . Further, the reaction mass was boiled for 30 hours. The solution became sticky and brown in color. Then the solution was cooled and unreacted reactants and by-products were distilled. The viscosity of the solution increased.

The resulting mixture was treated with isopropyl lithium in a ratio of 10 equivalents of isopropyllithium (1 M solution in hexane) to one equivalent of the resulting mixture (amino alcohol) in hexane at temperature of 50 °C. The concentration of active lithium (0.20 M) was determined by a standard method.

A I L glass reactor equipped with temperature and pressure sensors, a loading unit and a discharger, a mixer, and a jacket was loaded with a batch consisting of 350 g of nefras previously dried and deoxygenated, 46 g of butadiene, and 12 g of isoprene (in a weight ratio of monomers in the reaction medium of 80:20) . The temperature of delivering the batch to the reactor was minus 10 °C. When the temperature in the reactor reached 15 °C, a catalytic system consisting of a monolithium initiator prepared as disclosed above and an electron-donor additive was added thereto. The electron-donor additive included ethylene glycol di - tert-butyl ether in the form of a 0.066 M solution in nefras, based on a ratio of EGDTBE : lithium of 0.3 mol . The monolithium initiator was fed to the reactor in the form of a 0.20 M solution in nefras in an amount of 1.8 mol of the initiator per 100 g of monomers. The process of copolymerization was conducted at 50°C. When the conversion reached 95-100%, a monomer containing functional groups (4-trimethylsilylstyrene) was added in the form of a 0.052 M solution in an amount of 0.01% based on polymer; the reaction was continued for additional 30 minutes at the same temperature. The antioxidant used herein was agidol-2 taken in an amount of 0.01 wt . % .

The resulting product contained 36% of 1 , 2 -butadiene units, 41% of 3,4-isoprene units; glass transition temperature was -27°C; n=153,000; polydispersity was 1.7, and Mooney viscosity was 50 units. Example 5

One mole of epoxyhexane- 1 , 2 was added by drops to one mole of aniline for 1 hour at the boiling temperature of the solution of 126°C. Further, the reaction mass was boiled for 30 hours. The solution became sticky and brown in color. Then the solution was cooled and unreacted reactants and by-products were distilled. The viscosity of the solution increased.

The resulting mixture was boiled with sodium metal in nefras at temperature of 80 ^C 'C in a ratio of 3 equivalents of sodium to one equivalent of amino alcohol . Unreacted sodium was removed. The concentration of the introduced sodium (0.20 M) was determined by a standard Inductively Coupled Plasma-Mass Spectrometry method (ICP MS) .

A I L glass reactor equipped with temperature and pressure sensors, a loading unit and a discharger, a mixer, and a jacket was loaded with a batch consisting of 350 g of nefras previously dried and deoxygenated, 54 g of isoprene, and 16 styrene. The temperature of delivering the batch to the reactor was minus 10°C. When the temperature in the reactor reached 15 °C, a catalytic system consisting of a monolithium initiator prepared as disclosed above and an electron-donor additive was added thereto. The electron- donor additive included triethylamine in the form of a 0.089 M solution in nefras, based on a ratio of TEA: lithium of 20 mol . The monolithium initiator was fed to the reactor in the form of a 0.20 M solution in nefras in an amount of 1.6 mol of the initiator per 100 g of monomers. The process of copolymerization was conducted at 65°C to 100% conversion. When the conversion was complete, an antioxidant was added. The antioxidant used herein was agidol-2 taken in an amount of 0.5 wt . % .

The resulting product contained 47% of 3, 4 -isoprene units; glass transition temperature was -28°C; Mn=187 , 000 , polydispersity was 1.7, and Mooney viscosity was 67 units.

Example 6

One mole of epoxyhexane-1 , 2 (1 mol) was added by drops to one mole of aniline for 1 hour at the boiling temperature of the solution of 123°C. Further, the reaction mass was boiled for 30 hours. The solution became sticky and brown in color. Then the solution was cooled and unreacted reactants and by-products were distilled. The viscosity of the solution increased.

The resulting mixture was boiled with potassium metal in nefras at temperature of 70 °C at a ratio of 3 equivalents of potassium to one equivalent of the resulting mixture (amino alcohol) . Unreacted potassium was removed. The concentration of the introduced potassium was determined by a standard ICP MS method.

A I L glass reactor equipped with temperature and pressure sensors, a loading unit and a discharger, a mixer, and a jacket was loaded with a batch consisting of 350 g of nefras previously dried and deoxygenated, and 54 g of butadiene. The temperature of delivering the batch to the reactor was minus 10 °C. When the temperature in the reactor reached 15 °C, a catalytic system consisting of a monolithium initiator prepared as disclosed above and an electron-donor additive was added thereto. The electron- donor additive included ethylene glycol ethyl- ert-butyl ether in the form of a 0.050 M solution in nefras, based on a ratio of EGETBE : lithium of 0.8 mol. The monolithium initiator was fed to the reactor in the form of a 0.40 M solution in nefras in an amount of 2.0 mol of the initiator per 100 g of monomers. The process of copolymerization was conducted at 55 °C. When the conversion reached 95-100%, a functional group- containing monomer (4-triphenyltin styrene) was added in the form of a 0.058 M solution in an amount of 30% based polymer; the reaction was continued for additional 30 minutes at the same temperature. The antioxidant used herein was agidol-2 taken in an amount of 0.5 wt . % .

The resulting product contained 58% of 1 , 2 -butadiene units, glass transition temperature was -21°C, Mn=150 , 000 , polydispersity was 1.6, and Mooney viscosity was 49 units.

Example 7

One mole of epoxyhexane - 1 , 2 was added by drops to one mole of aniline for 1 hour at the boiling temperature of the solution (between 120 and 130°C) . Further, the reaction mass was boiled for 15 hours. The solution became sticky and brown in color. Then the solution was cooled and unreacted reactants and by-products were distilled. The viscosity of the solution increased.

A I L glass reactor equipped with temperature and pressure sensors, a loading unit and a discharger, a mixer, and a jacket was loaded with a batch consisting of 350 g of nefras previously dried and deoxygenated, 46 g of butadiene, and 12 g of styrene (in a weight ratio of monomers in the reaction medium of 79:21) . The temperature of delivering the batch to the reactor was minus 10 °C. When the temperature in the reactor reached 15 °C, 1 ml of the resulting mixture (amino alcohol) , 8 ml of .n-butyllithium (0.8 M solution in hexane) , and an electron-donor additive was added thereto. The electron-donor additive included ditetrahydrofurylpropane (DTHFP) in the form of a 0.089 M solution in nefras, based on a ratio of DTHFP : lithium of 0.6 mol . The process of copolymerization was conducted at 55°C. When the conversion reached 95-100%, a functionalizing agent (Michler's ketone) was added in the form of a 0.038 M solution in a molar ratio to Li of 2; the reaction was continued for additional 30 minutes at temperature of 60 °C.

The antioxidant used herein was agidol-2 taken in an amount of 0.5 wt . % .

The resulting product had the following characteristics: the amount of styrene is 21 wt.%; the amount of 1 , 2 -butadiene units per polybutadiene is 65 wt.%; glass-transition point is-21°C; Mn = 140,000; polydispersity is 1.7; and Mooney viscosity equals to 46 units.

Physico-rnechanical and elastic-hysteresis properties of the vulcanizate based on the rubber prepared according to Example 7 are given in Table 1.

Example 8

One mole of epoxyoctane-1 , 2 was added by drops to one mole of aniline for 1 hour at the boiling temperature of the solution of 163 °C. Further, the reaction mass was boiled for 22 hours. The solution became sticky and brown in color. Then the solution was cooled and unreacted reactants and by-products were distilled. The viscosity of the solution increased.

A I L glass reactor equipped with temperature and pressure sensors, a loading unit and a discharger, a mixer, and a jacket was loaded with a batch consisting of 350 g of nefras previously dried and deoxygenated, 54 g of butadiene, and 6 g of styrene (in a weight ratio of monomers in the reaction medium of 90:10). The temperature of delivering the batch to the reactor was -5°C. When the temperature in the reactor reached 15 °C, 1 ml of the resulting mixture (amino alcohol) , 8 ml of n-butyllithium (0.8 M solution in hexane) , and an electron-donor additive was added thereto. The electron-donor additive included tripiperidinophosphine oxide in the form of a 0.060 M solution in nefras, based on a ratio of TPPO: lithium of 10 mol. The process of copolymerization was conducted at 40°C. When the conversion reached 95-100%, a functional group- containing monomer (Ν,Ν' -bis (trimethylsilyl) aminomethyl styrene) was added in the form of a 0.021 M solution in an amount of 20% based on weight of polymer; the reaction was continued for additional 30 minutes at temperature of 70 °C.

The antioxidant used herein was agidol-2 taken in an amount of 0.5 wt . % .

The resulting product had the following characteristics: the amount of styrene is 11 wt.%; the amount of 1 , 2 -butadiene units per polybutadiene is 72 wt.%; glass- transition point is -15°C; Mn = 160,000; polydispersity is 1.8; and Mooney viscosity equals to 61 units.

Physico-mechanical and elastic-hysteresis properties of the vulcanizate based on the rubber prepared according to Example 8 are given in Table 1.

Table 1. Comparative characteristic of the vulcanizates produced from the rubbers prepared as disclosed in the examples with the vulcanizates produced from the rubbers disclosed in the US patent No. 5959048.

As can be seen from Table 1, the use of the initiators according to the present invention in the synthesis of rubbers provides obtaining of vulcanizates based on said rubbers with substantially enhanced elastic-hysteresis properties, in particular rolling resistance, while maintaining or improving the characteristics such as stress strain properties and wear resistance.