Process for producing cis-1,4-polydienes

Abstract

This invention relates to the field of synthetic rubber, which can be used to manufacture tires / various rubber products and for the modification of plastics. A method for producing cis-1,4-polydiene by (co)polymerizing conjugated dienes in a hydrocarbon solvent in the presence of a Ziegler-Natta catalyst composed of a lanthanide carboxylate, an alkylaluminum, and a halogen-containing component formed in two ways: pre-forming and in-situ. The proposed solution also considers the possibility of modifying the resulting rubber by introducing aminosilanes from a group containing alkoxy groups and / or from a group of halogen-containing compounds. This invention expands the scope of methods for producing highly stereoregular (co)polymers of conjugated dienes and makes it possible to obtain a variety of rubbers depending on the desired properties and applications.

Description

Technical Field

[0001] This invention relates to the field of synthetic rubber, which can be used to manufacture tires / various rubber products and for the modification of plastics. More specifically, this invention relates to a method for synthesizing cis-1,4-polydiene by (co)polymerization of butadiene and isoprene in a hydrocarbon solvent medium in the presence of a rare-earth element-based Ziegler-Natta catalyst. The proposed method allows for the acquisition of cis-1,4-polydiene with a high content (greater than 95%) of cis-1,4-chain and low (1.5-2.8) and high (2.8-4.0) polydispersity indices, and the resulting rubber is characterized by improved processability, and the rubber-based products are characterized by high-performance properties. Background Technology

[0002] General-purpose stereoregular rubbers are indispensable in tire tread and sidewall formulations. Meanwhile, modern rubbers based on these rubbers demand improved processability, reduced hysteresis loss, and increased durability. These parameters are determined by the structure of the polydiene macromolecules (i.e., microstructure – the content of cis-1,4-chains) and macrostructure – molecular weight distribution and linearity / branching.

[0003] RU 2638960 C2 discloses a method for producing high molecular weight polybutadiene with a cis-1,4-chain content greater than 95% by gradually increasing Mooney viscosity. According to known methods, 1,3-butadiene is polymerized at a temperature of 50°C to 120°C, polymerization is terminated by adding a protonated compound to cement, and sulfur chloride is added to the cement prior to the addition, after the cement has been treated with a plant-derived fatty acid ether (i.e., epoxidized soybean oil). This method allows for an increase of at least 50% in the Mooney viscosity of the initial polymer after polymerization, thereby ensuring either no gel formation or only slight gel formation. Furthermore, when using a catalyst, the invention does not specify a range of monomer concentrations in the feed polymerization, the preparation of which is mentioned in the claims. The maximum butadiene concentration of 13 wt% described in the examples does not meet the requirements of modern rubber production, where this parameter can be adjusted based on the available solvents and the necessary technical and economic indicators of the process.

[0004] US 7112632 B2 discloses a method for producing cis-1,4-polybutadiene with low branching, comprising polymerizing butadiene in an organic solvent at a temperature of 20°C to 120°C in the presence of a neodymium compound-based catalyst, while simultaneously modifying the product at a temperature of 20°C to 150°C with a product derived from unsaturated natural oils, oligomers, or copolymers of butadiene and / or isoprene functionalized with epoxy, anhydride, or ether groups. The rubber obtained by this method is characterized by a cis-1,4-chain content of not less than 93%, low polydispersity (not exceeding 2.5%), and low cold flow. However, a drawback of this solution is that the modified polymer is characterized by a high content of high molecular weight fractions, which deteriorates the processability of the rubber and the dynamic properties of the rubber-based vulcanizates.

[0005] RU 2701930 C1 discloses a method for polymerizing conjugated dienes in an organic solvent medium. The method includes the following steps: preparing a catalytic system; performing diene polymerization in an organic solvent using the catalytic system; introducing a comonomer when the conjugated diene conversion reaches at least 96%; and introducing at least one branching agent. The catalytic system comprises a lanthanide element, a conjugated diene, an alkylaluminum, and a halogen-containing component. The comonomer is selected from cyclic hydroxy acid esters containing 2 to 10 carbon atoms in the ring, and the branching agent is selected from the group consisting of silicon chloride or tin compounds. This method provides for obtaining diene copolymers characterized by improved technical properties during rubber compounding, improved processability of the rubber compound, and improved copolymer interactions. However, in this solution, the polymerization time is 1.5 h to 3 h, indicating that the proposed catalyst activity is insufficient or the monomer concentration in the feed is low, leading to reduced technical and economic indicators of production, and consequently, reduced rubber yield.

[0006] WO 2009121516 A1 discloses a method for producing polybutadiene with a cis-1,4-chain content greater than 92%, a Mooney viscosity of 30 to 70, a Mw / Mn ratio of 1.5 to 4, and a branching ratio (gM) of 0.4 to 0.9. The method is characterized by performing butadiene polymerization in an aliphatic and / or alicyclic solvent system in the presence of an in-situ obtained catalyst, wherein the catalytic system is obtained by dissolving a neodymium carboxylate in a process solvent in a continuous mode within a temperature range of 70°C to 130°C in the presence of an alkyl aluminum compound. This invention allows for the continuous production of polymers with polydispersity ranging from 1.5 to 4.0. A disadvantage of this method is the low stereoregularity level of the resulting rubber. The reduced cis-1,4-chain content in the polymer leads to a deterioration in the strength and abrasion resistance of the rubber-based vulcanized rubber.

[0007] RU 2803602 C1 discloses a method for producing modified polydiene, comprising the steps of: (i) preparing a catalytic complex comprising (A) a lanthanide compound, (B) a conjugated diene, (C) an alkylaluminum, and (D) a halogen-containing component; (ii) polymerizing the conjugated diene in an organic solvent medium in the presence of the catalytic complex obtained in step (i); (iii) introducing a modifier, i.e., a low molecular weight polybutadiene containing a terminal alkoxysilyl group, into the polymer when at least 96% monomer conversion is achieved; and (iv) rapidly stopping the polymerization obtained in step (iii), introducing an antioxidant, and separating the polymer. The modified polydiene obtained according to the invention is characterized by a Mooney viscosity of 40 to 50 Mooney units and a content of greater than 96% cis-1,4-chain. This method allows for the production of polydienes characterized by improved processability and filler interaction properties within a polymer matrix. RU 2803602 C1 does not specify the catalyst-to-monomer dosage ratio, and the polymerization process lasts for a considerable period of 2 hours. Furthermore, the resulting polymer exhibits viscosity limitations (40 to 50 Mooney units after modification), which, due to the reduced number of free chain ends, limits the improvement in hysteresis loss of the vulcanized rubber. Summary of the Invention

[0008] The technical problem to be solved by the present invention is to develop a novel method for producing cis-1,4-polydiene with a high content of cis-1,4-chain and low (1.5-2.8) and high (2.8-4.0) polydispersity indices, wherein the resulting rubber is characterized by improved processability, and the rubber-based products are characterized by high performance properties, particularly high tensile strength, low rolling resistance and high freeze resistance of vulcanized rubber.

[0009] This result was achieved by polymerizing conjugated dienes using highly active and stereooriented catalysts prepared via two methods: preforming or incorporating the catalyst component into the monomer solution. The former is characterized by the high stability of the active center and allows for flexible action against poisons present in the polymerization system, while the latter excludes the catalyst synthesis and aging stages, which are important for operation and allow for viscosity adjustment during production. Improvements in rubber processability can be achieved by increasing the content of low molecular weight fractions to produce cis-1,4-polydienes with relatively high polydispersity; however, this approach has limitations as it affects the hysteresis loss level of the vulcanized rubber. Where a complex solution is required, multidirectional modifiers can be used alone or in combination. In particular, products based on, for example, disulfur dichloride, react along the double bonds of the polymer chain. During modification, the SS bonds appear in the polymer structure and subsequently break under mechanical stress in the rubber mixer, thereby contributing to improved homogeneity of the rubber mixture, reduced equipment load, and thus improved polymer processability, even with increased base rubber viscosity. Simultaneously, products such as aminosilanes containing alkoxy groups and tin halides react at the active centers of the "active" polymer chains. As a result of this reaction, polydienes containing modifier functional groups or metal atoms at the chain ends are obtained. It should be noted that the interaction strength between these groups and the surface of fillers (carbon black or silica fillers) in the rubber mixture determines the efficiency of the modification. Therefore, the modification of reactive macromolecules generally pursues two goals: first, to improve the elastoplastic properties of the rubber itself; and second, to improve the properties of rubber blends and vulcanized rubbers based on modified polymers. Polybutadiene obtained using rare earth metal-based catalysts is characterized by lower freeze-thaw resistance levels than other polybutadienes, due to the high crystallinity resulting from the high stereoregularity of the macromolecules. An effective method to improve low-temperature properties is the copolymerization of butadiene with a small amount of isoprene. When the isoprene chain content in the copolymer is 12% to 16%, the crystallization rate of the copolymer is already equal to that of titanium-based polybutadiene [FEKuperman, New Rubber for Tyres, Moscow, 2009]. Therefore, the proposed solution allows for the adjustment of the process parameters to optimize its technical and economic performance, and to obtain a variety of rubbers depending on the desired properties and application areas.

[0010] According to the present invention, a method for producing cis-1,4-polydiene comprises several steps: synthesizing a catalytic complex based on a rare earth metal carboxylate, performing a (co)polymerization process in a hydrocarbon solvent, and, in some cases, modification. In this case, the catalyst is initially prepared by mixing the rare earth metal carboxylate (A), alkyl aluminum (B), and halogen source (C) in an aliphatic, cycloalkane solvent, or a mixture thereof with the addition of a small amount of conjugated diene (pre-forming), or by directly introducing the catalyst components into the monomer solution during polymer synthesis (in situ). The cis-1,4-polybutadiene cement is then blended with a modifier and / or a quick-stopping agent, such that the total dosage of the modifier and / or the quick-stopping agent is 0 wt% to 1.0 wt% relative to the polymer.

[0011] Neodymium, praseodymium, gadolinium, or mixtures thereof are used as rare earth metals in rare earth metal carboxylates.

[0012] Diisobutylaluminum hydride (DIBAH), triethylaluminum (TEA), triisobutylaluminum (TIBA), isobutylaluminoxane (IBAO), methylaluminoxane (MAO), including modified grades of the methylaluminoxane, or mixtures thereof, can be used as the alkylaluminum in the catalytic system. The alkylaluminum in the catalytic system can be introduced at any stage of catalyst preforming, and the aluminum oxane can be used either as a mixture with standard alkylaluminum or alone by introducing the aluminum oxane as a final component in complex formation.

[0013] As halogenating agents in the catalytic system, but not limited to, ethyl sesquialuminium chloride (EASC), diethyl aluminum chloride (DEAC), ethyl aluminum chloride (EADC), diisobutyl aluminum chloride (DIBAC), or mixtures thereof are used as halogenating agents in the catalytic system.

[0014] The polymerization is carried out in a continuous or intermittent manner. The polymerization time is from 0.5 h to 2 h, preferably 1 h. The monomer concentration in the solvent is from 10 wt% to 50 wt%, preferably 15 wt% to 25 wt%. The feed temperature ranges from -20 °C to 30 °C, preferably -15 °C to 30 °C. The final temperature of the polymerization process ranges from 70 °C to 150 °C, preferably 70 °C to 125 °C.

[0015] The solvent is n-hexane, hexane isomers, cyclohexane, or mixtures thereof.

[0016] Conjugated dienes are, but not limited to, butadiene-1,3, isoprene, or mixtures thereof.

[0017] The modifier is selected from compounds of various aminosilanes containing an alkoxy group, examples of which include, but are not limited to, N-(3-triethoxysilylpropyl)cyclohexylamine, 3-triethoxysilyl-N-(1,3-dimethylbutylene)propylamine, N-[3-diethoxy(methyl)silyl]propyl]-4-methylpentan-2-amine, N-[3-dimethoxy(methyl)silyl)propyl]cyclohexylamine, N-(6-aminohexyl)aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, or the modifier is selected from a mixture of various halogen-containing compounds, such as disulfide dichloride, phosphorus trichloride, phosphorus pentachloride, tin pentachloride, or mixtures thereof.

[0018] The quick-stopping agent is selected from, but not limited to, neodecanoic acid, stearic acid, lauric acid, or water, preferably demineralized water. In the case of neodecanoic acid, stearic acid, and lauric acid, or mixtures thereof, the dosage of the quick-stopping agent is 0 wt% to 0.5 wt% relative to the polymer, or in the case of water as the quick-stopping agent, the cement / water mass ratio is 1 / 0.1.

[0019] The feeding sequence of the modifier and the quick-stopping agent can be any of the following: modifier-quick-stopping agent, modifier-quick-stopping agent-modifier, quick-stopping agent-modifier, (without quick-stopping agent) modifier, (without modifier) ​​quick-stopping agent.

[0020] The cement and modifier / quick-stop agent are mixed in a static mixer and / or a dynamic mixer as follows:

[0021] - The monomer conversion rate before the modifier is fed is 60% to 99%, preferably greater than 95%;

[0022] - Modification time ranges from 5 minutes to 3 hours;

[0023] - The modification temperature is 70°C to 150°C, preferably 70°C to 110°C.

[0024] The resulting polymer has the following properties:

[0025] -Mn at 7×10 4 g / mol up to 48×10 4 Within the range of g / mol

[0026] -Mw / Mn in the range of 1.5 to 4.0

[0027] Mooney viscosity (ML1+4, 100°C) is 30 MU to 90 MU.

[0028] The content of -cis-1,4-chain is at least 95%. Detailed Implementation

[0029] The following are examples of the proposed invention that have been carried out. These examples are not intended to limit the scope of protection of the invention, but are provided for illustrative purposes.

[0030] Examples of the preparation of cis-1,4-polydiene are shown in Tables 1 and 2.

[0031] Table 1. Catalyst Synthesis and Polymerization

[0032]

[0033]

[0034] Table 2. Modification and Quick Stop

[0035]

[0036]

[0037] Example 1

[0038] Catalyst preparation.

[0039] The glass reactor was preheated under vacuum and filled with nitrogen. Then, a solution of neodymium neodecanoate (A) - 1 ml (0.32 mmol), DIBAH (B) - 4.95 ml (4.73 mmol), conjugated diene, and DEAC (C) - 0.94 ml (1.11 mmol) was introduced into the reactor with stirring. The molar ratio of the components was A:B:C = 1:15:3.5. The prepared complex was aged at 20°C to 25°C for at least 12 h, but not exceeding 24 h. The concentration of neodymium in the prepared catalyst was 0.041 g at / L.

[0040] Polymerization and modification.

[0041] In a pre-prepared metal reactor (washed with a solvent containing any alkyl aluminum), 750 ml of a 15 wt% monomer concentration feed (a mixture of naphtha and butadiene-1,3) was introduced under stirring. The reactor temperature was adjusted to 10 °C, and 1.71 ml of catalyst was introduced, wherein the butadiene-1,3 / Nd ratio was 20,000 mol / mol. After reaching the desired conversion at 95 °C, a modifier—disulfur dichloride—was introduced at a dose equal to 0.1 g / 100 g of the polymer. The reactor contents were stirred for 30 min. The reactor was then removed, the polymer was stabilized with a non-staining antioxidant, degassed, and dried to constant weight.

[0042] Example 2

[0043] Catalyst preparation.

[0044] The glass reactor was preheated under vacuum and filled with nitrogen. Then, under stirring, a solution of neodymium neodecanoate (A) - 1 ml (0.32 mmol), a mixture of DIBAH and MAO (B) - 15.01 ml (6.33 mmol + 6.33 mol), and conjugated diene and EADC (C) - 0.94 ml (1.11 mmol chlorine) was introduced into the reactor. The molar ratio of the components was A:B:C = 1:40:3.5. The prepared complex was aged at a temperature of 20°C to 25°C for at least 12 h, but not exceeding 24 h. The concentration of neodymium in the prepared catalyst was 0.018 g at / L.

[0045] Polymerization and modification.

[0046] 750 ml of a 15 wt% monomer concentration feed (a mixture of cyclohexane and butadiene-1,3) was introduced into a pre-prepared metal reactor (washed with a solvent containing any alkyl aluminum) under stirring. The reactor temperature was adjusted to 10 °C, and 1.97 ml of catalyst was introduced, wherein the butadiene-1,3 / Nd ratio was 40,000 mol / mol. After reaching the desired conversion at 95 °C, the modifier 3-triethoxysilyl-N-(1,3-dimethylbutylene)propylamine was introduced at a dose equal to 0.015 g / 100 g of the polymer. The reactor contents were stirred for 30 min. Additionally, a quick-stopping agent, neodecanoic acid, at a dose equal to 0.012 g / 100 g of the polymer, was introduced into the reaction mixture and stirred for 5 min to 15 min. The reactor was then removed, the polymer was stabilized with a non-staining antioxidant, degassed, and dried to constant weight.

[0047] Example 3

[0048] Catalyst preparation.

[0049] The glass reactor was preheated under vacuum and filled with nitrogen. Then, under stirring, a solution of neodymium neodecanoate (A) - 1 ml (0.32 mmol), a mixture of DIBAH, TIBA, and TEA (B) - 6.37 ml (1.91 mmol + 4.11 mmol + 0.32 mmol), a mixture of conjugated diene and EASC and EADC (C) - 0.67 ml (0.79 mmol chlorine) was introduced into the reactor. The molar ratio of the components was A:B:C = 1:20:2.5. The prepared complex was aged at 20°C to 25°C for at least 12 h, but not exceeding 24 h. The concentration of neodymium in the prepared catalyst was 0.032 g at / L.

[0050] polymerization.

[0051] In a pre-prepared metal reactor (washed with a solvent containing any alkyl aluminum), 750 ml of a feed (a mixture of hexane and isoprene) with a monomer concentration of 18 wt% was introduced under stirring. The reactor temperature was adjusted to 10 °C, and 2.06 ml of catalyst was introduced, wherein the isoprene / Nd ratio was 20,000 mol / mol. After reaching the desired conversion, the reactor was removed, and the resulting cement was vigorously stirred with demineralized water. The polymer was then stabilized with a non-staining antioxidant, degassed, and dried to constant weight.

[0052] Example 4

[0053] Catalyst preparation.

[0054] The glass reactor was preheated under vacuum and filled with nitrogen. Then, under stirring, a solution of neodymium neodecanoate (A) - 1 ml (0.32 mmol), MAO (B) - 46.9 ml (47.43 mmol), conjugated diene, and EASC (C) - 0.27 ml (0.32 mmol chlorine) was introduced into the reactor. The molar ratio of the components was A:B:C = 1:150:1.0. The prepared complex was aged at 20°C to 25°C for at least 12 h, but not exceeding 24 h. The concentration of neodymium in the prepared catalyst was 0.006 g at / L.

[0055] polymerization.

[0056] In a pre-prepared metal reactor (washed with a solvent containing any alkyl aluminum), 750 ml of a feed (a mixture of petroleum solvent, butadiene-1,3, and isoprene) with a total monomer concentration of 20 wt% was introduced under stirring. The reactor temperature was adjusted to -10 °C, and 7.79 ml of catalyst was introduced, wherein the butadiene-1,3+isoprene / Nd ratio was 35,000 mol / mol. After reaching the desired conversion, the reactor was removed, and the resulting cement was vigorously stirred with demineralized water. The polymer was then stabilized with a non-staining antioxidant, degassed, and dried to constant weight.

[0057] Example 5

[0058] Catalyst preparation.

[0059] The glass reactor was preheated under vacuum and filled with nitrogen. Then, under stirring, a solution of gadolinium neodecanoate (A) - 1 ml (0.29 mmol), a mixture of DIBAH and MAO (B) - 28.31 ml (8.7 mmol + 14.49 mmol), and a mixture of conjugated diene and EASC and DIBAC (C) - 0.86 ml (1.01 mmol chlorine) was introduced into the reactor. The molar ratio of the components was A:B:C = 1:80:3.5. The prepared complex was aged at 20°C to 25°C for at least 12 h, but not exceeding 24 h. The neodymium concentration in the prepared catalyst was 0.009 g at / L.

[0060] Polymerization and modification.

[0061] In a pre-prepared metal reactor (washed with a solvent containing any alkyl aluminum), 750 ml of a 15 wt% monomer concentration feed (a mixture of cyclohexane and butadiene-1,3) was introduced under stirring. The reactor temperature was adjusted to 5 °C, and 3.28 ml of catalyst was introduced, wherein the butadiene-1,3 / Nd ratio was 50,000 mol / mol. After reaching the desired conversion at 100 °C, the modifier N-(6-aminohexyl)aminopropyltrimethoxysilane was introduced at a dosage of 0.011 g / 100 g of polymer. The reactor contents were stirred for 60 min. Then, a quick-stopping agent stearic acid at a dosage of 0.02 g / 100 g of polymer was introduced into the reaction mixture and stirred for 5 min to 15 min. The reactor was then removed, the polymer was stabilized with a non-staining antioxidant, the polymer was degassed, and dried to constant weight.

[0062] Example 6

[0063] Catalyst preparation.

[0064] The glass reactor was preheated under vacuum and filled with nitrogen. Then, under stirring, a solution of neodymium neodecanoate (A) - 1 ml (0.32 mmol), a mixture of DIBAH and MAO (B) - 7.95 ml (1.58 mmol + 4.75 mmol), a conjugated diene, and DIBAC (C) - 0.27 ml (0.32 mmol chlorine) was introduced into the reactor. The molar ratio of the components was A:B:C = 1:20:1. The prepared complex was aged at 20°C to 25°C for at least 12 h, but not exceeding 24 h. The concentration of neodymium in the prepared catalyst was 0.032 g at / L.

[0065] Polymerization and modification.

[0066] In a pre-prepared metal reactor (washed with a solvent containing any alkyl aluminum), 750 ml of a feed (a mixture of petroleum solvent and butadiene-1,3) with a monomer concentration of 18 wt% was introduced under stirring. The reactor temperature was adjusted to 0 °C, and 3.57 ml of catalyst was introduced, wherein the butadiene-1,3 / Nd ratio was 15,000 mol / mol. After reaching the desired conversion at 103 °C, a modifier—phosphorus trichloride—was introduced at a dosage of 0.15 g / 100 g of polymer. Stirring of the reactor contents was performed for 60 minutes. The reactor was then removed, the polymer was stabilized with a non-staining antioxidant, degassed, and dried to constant weight.

[0067] Example 7

[0068] Catalyst preparation.

[0069] The glass reactor was preheated under vacuum and filled with nitrogen. Next, a solution of neodymium neodecanoate (A) - 1 ml (0.32 mmol), DIBAH (B) - 4.98 ml (4.76 mmol), conjugated diene, and EASC (C) - 0.67 ml (0.79 mmol chlorine) was introduced into the reactor under stirring. The molar ratio of the components was A:B:C = 1:15:2.5. The prepared complex was aged at 20°C to 25°C for at least 12 h, but not exceeding 24 h. The neodymium concentration in the prepared catalyst was 0.042 g at / L.

[0070] polymerization.

[0071] In a pre-prepared metal reactor (washed with a solvent containing any alkyl aluminum), 750 ml of a 15 wt% monomer concentration feed (a mixture of hexane and butadiene-1,3) was introduced under stirring. The reactor temperature was adjusted to 20 °C, and 1.56 ml of catalyst was introduced, wherein the butadiene-1,3 / Nd ratio was 20,000 mol / mol. After reaching the desired conversion, the reactor was removed, the polymer was stabilized with a non-staining antioxidant, and the polymer was degassed and dried to constant weight.

[0072] Example 8

[0073] Catalyst preparation.

[0074] The glass reactor was preheated under vacuum and filled with nitrogen. Then, under stirring, a solution of praseodymium neodecanoate (A) - 1 ml (0.32 mmol), a mixture of TIBA and IBAO (B) - 39.95 ml (16.17 mmol + 16.17 mmol), a conjugated diene, and EASC (C) - 0.27 ml (0.32 mmol chlorine) was introduced into the reactor. The molar ratio of the components was A:B:C = 1:100:1. The prepared complex was aged at 20°C to 25°C for at least 12 h, but not exceeding 24 h. The neodymium concentration in the prepared catalyst was 0.008 g at / L.

[0075] Polymerization and modification.

[0076] In a pre-prepared metal reactor (washed with a solvent containing any alkyl aluminum), 750 ml of a 13 wt% monomer concentration feed (a mixture of hexane and butadiene-1,3) was introduced under stirring. The reactor temperature was adjusted to 30 °C, and 3.95 ml of catalyst was introduced, wherein the butadiene-1,3 / Nd ratio was 40,000 mol / mol. After reaching the desired conversion at 103 °C, a modifier solution—N-(3-triethoxysilylpropyl)cyclohexylamine—was introduced at a dosage of 0.014 g / 100 g of polymer. The reactor contents were stirred for 60 min. Then, a quick-stopping agent—stearic acid—was introduced at a dosage of 0.05 g / 100 g of polymer, and stirring was resumed for 5 to 15 min. Subsequently, a second modifier—disulfur dichloride—was added to the reaction mixture at a dosage of 0.12 g / 100 g of polymer, and stirring was resumed for another 120 min. The reactor was then removed, the polymer was stabilized with a non-staining antioxidant, and the polymer was degassed and dried to constant weight.

[0077] Example 9

[0078] Catalyst preparation.

[0079] The glass reactor was preheated under vacuum and filled with nitrogen. Then, under stirring, a solution of neodymium neodecanoate and gadolinium (A) - 1 ml (0.30 mmol), DIBAH and TIBA (B) - 4.5 ml (2.44 mol + 1.52 mmol), and conjugated diene and EASC (C) - 0.9 ml (1.06 mmol chlorine) was introduced into the reactor. The molar ratio of the components was A:B:C = 1:13:3.5. The prepared complex was aged at 20°C to 25°C for at least 12 h, but not exceeding 24 h. The neodymium concentration in the prepared catalyst was 0.042 gat / L.

[0080] Polymerization and modification.

[0081] In a pre-prepared metal reactor (washed with a solvent containing any alkyl aluminum), 750 ml of a 15 wt% monomer concentration feed (a mixture of hexane and butadiene-1,3) was introduced under stirring. The reactor temperature was adjusted to 20 °C, and 1.66 ml of catalyst was introduced, wherein the butadiene-1,3 / Nd ratio was 20,000 mol / mol. After the desired conversion was achieved and the temperature was brought to 70 °C, a modifier—tin tetrachloride—was introduced at a dosage equal to 0.25 g / 100 g of the polymer.

[0082] The reactor contents should be stirred for 30 minutes. Then, remove the reactor, stabilize the polymer with a non-staining antioxidant, degas the polymer, and dry it to constant weight.

[0083] Example 10

[0084] Catalyst preparation.

[0085] The glass reactor was preheated under vacuum and filled with nitrogen. Then, under stirring, a solution of 1 ml (0.3 mmol) of a mixture of neodymium neodecanoate and gadolinium neodecanoate (A), 5.75 ml (4.54 mmol + 1.51 mmol) of a mixture of DIBAH and modified MAO (B), and 0.76 ml (0.90 mmol chlorine) of a mixture of conjugated diene and EASC and DEAC (C) was introduced into the reactor. The molar ratio of the components was A:B:C = 1:20:3.0. The prepared complex was aged at 20°C to 25°C for at least 12 h, but not exceeding 24 h. The concentration of neodymium in the prepared catalyst was 0.037 g at / L.

[0086] polymerization.

[0087] In a pre-prepared metal reactor (washed with a solvent containing any alkyl aluminum), 750 ml of a 15 wt% monomer concentration feed (a mixture of hexane and butadiene-1,3) was introduced under stirring. The reactor temperature was adjusted to 15 °C, and 1.28 ml of catalyst was introduced, wherein the butadiene-1,3 / Nd ratio was 30,000 mol / mol. After reaching the desired conversion, the reactor was removed, and the resulting polymer was vigorously stirred with demineralized water, then stabilized with a non-staining antioxidant, degassed, and dried to constant weight.

[0088] Example 11

[0089] polymerization.

[0090] In a pre-prepared metal reactor (washed with a solvent containing any alkyl aluminum), 750 ml of a 20 wt% monomer concentration feed (a mixture of hexane and butadiene-1,3) was introduced under stirring. The reactor temperature was adjusted to 0 °C, and a solution of 0.65 ml (0.62 mmol) of DIBAH(B), 0.39 ml (0.125 mmol) of neodymium neodecanoate(A), and 0.26 ml (0.31 mmol) of EASC(C) was continuously introduced. In this case, the molar ratio of the components was A:B:C = 1:5:2.5, with a butadiene-1,3 / Nd ratio of 15,000 mol / mol. After reaching the desired conversion, the reactor was removed, the resulting polymer was vigorously stirred with demineralized water, stabilized with a non-staining antioxidant, degassed, and dried to constant weight.

[0091] Example 12

[0092] Polymerization and modification.

[0093] In a pre-prepared metal reactor (washed with a solvent containing any alkyl aluminum), 750 ml of a 15 wt% monomer concentration feed (a mixture of hexane and butadiene-1,3) was introduced under stirring. The reactor temperature was adjusted to 0 °C, and a solution of 1.52 ml (1.19 mmol + 0.21 mmol) of a mixture of DIBAH and TIBA (B), 0.22 ml (0.070 mmol) of neodymium neodecanoate (A), and 0.18 ml (0.21 mmol) of a mixture of EASC and EADC (C) was continuously introduced. The molar ratio of the components was A:B:C = 1:20:3, with a butadiene-1,3 / Nd ratio of 20,000 mol / mol. After reaching the desired conversion at 90 °C, a quick-stopping agent—neodecanonical acid—was added at a dosage of 0.5 g / 100 g of polymer, followed by a modifier solution—disulfur dichloride—at a ratio of 0.3 g / 100 g of polymer. The reactor contents should be stirred for 15 minutes. Then, remove the reactor, stabilize the polymer with a non-staining antioxidant, degas the polymer, and dry it to constant weight.

[0094] Example 13

[0095] Polymerization and modification.

[0096] In a pre-prepared metal reactor (washed with a solvent containing any alkyl aluminum), 750 ml of a feed (a mixture of hexane and butadiene-1,3) with a monomer concentration of 18 wt% was introduced under stirring. The reactor temperature was adjusted to 0 °C, and a solution of 1.44 ml (0.84 mmol + 0.42 mmol) of a mixture of DIBHA and MAO (B), 0.13 ml (0.042 mmol) of neodymium neodecanoate (A), and 0.11 ml (0.13 mmol) of DIBAC (C) (chlorine) was continuously introduced. In this case, the molar ratio of the components was A:B:C = 1:30:3, with a butadiene-1,3 / Nd ratio of 40,000 mol / mol. After reaching the desired conversion at 102 °C, a solution of the modifier 3-aminopropyltrimethoxysilane was added at a rate of 0.012 g / 100 g of polymer. The reactor contents were stirred for 5 minutes. Then, add lauric acid as a quick-stopping agent at a concentration of 0.03 g / 100 g of the polymer, and stir for another 5 to 15 minutes. The reactor is then removed, the polymer is stabilized with a non-staining antioxidant, degassed, and dried to constant weight.

[0097] Example 14

[0098] polymerization.

[0099] In a pre-prepared metal reactor (washed with a solvent containing any alkyl aluminum), 750 ml of a 25 wt% monomer concentration feed (a mixture of hexane and butadiene-1,3) was introduced under stirring. The reactor temperature was adjusted to -10 °C, and a solution of 4.90 ml (4.69 mmol) of DIBAH (B), 0.3 ml (0.09 mmol) of neodymium neodecanoate (A), and 0.17 ml (0.20 mmol) of a mixture of EASC and DEAC (C) was continuously introduced. In this case, the molar ratio of the components was A:B:C = 1:50:2.0, with a butadiene-1,3 / Nd ratio of 25,000 mol / mol. After reaching the desired conversion, the reactor was removed, the resulting polymer was vigorously stirred with demineralized water, stabilized with a non-staining antioxidant, degassed, and dried to constant weight.

[0100] Example 15

[0101] Polymerization and modification.

[0102] In a pre-prepared metal reactor (washed with a solvent containing any alkyl aluminum), 750 ml of a 15 wt% monomer concentration feed (a mixture of hexane and butadiene-1,3) was introduced under stirring. The reactor temperature was adjusted to 10 °C, and a solution of 1.71 ml (0.47 mmol + 0.94 mmol) of a mixture of TIBA and IBAO (B), 0.15 ml (0.047 mmol) of neodymium neodecanoate and praseodymium neodecanoate (A), and 0.14 ml (0.17 mmol chlorine) of DEAC (C) was continuously introduced. In this case, the molar ratio of the components was A:B:C = 1:30:3.5, with a butadiene-1,3 / Nd ratio of 30,000 mol / mol.

[0103] After achieving the desired conversion at 95°C, a solution of the modifier N-(2-aminoethyl)-3-aminopropyltrimethoxysilane is introduced at a dosage of 0.027 g / 100 g of the polymer. The reactor contents are stirred for 45 minutes. Then, a quick-stopping agent—stearic acid—is introduced at a dosage of 0.1 g / 100 g of the polymer, and the mixture is stirred for another 5 to 15 minutes. Subsequently, a second modifier—phosphorus pentachloride—is added to the reaction mixture at a dosage of 0.3 g / 100 g of the polymer, and the mixture is stirred for another 45 minutes. The reactor is then removed, the polymer is stabilized with a non-staining antioxidant, and the polymer is degassed and dried to constant weight.

[0104] Example 16

[0105] polymerization.

[0106] In a pre-prepared metal reactor (washed with a solvent containing any alkyl aluminum), 750 ml of a feed (a mixture of hexane, butadiene-1,3, and isoprene) with a total monomer concentration of 20 wt% was introduced under stirring. The reactor temperature was adjusted to 0 °C, and a solution of 1.99 ml (1.23 mmol) of DIBAH (B), 0.25 ml (0.082 mmol) of praseodymium neodecanoate (A), and 0.21 ml (0.25 mmol) of EASC (C) (chlorine) was continuously introduced. In this case, the molar ratio of the components was A:B:C = 1:15:3.0, with a butadiene-1,3+ isoprene / Nd ratio of 22,000 mol / mol. After reaching the desired conversion, the reactor was removed, the resulting polymer was vigorously stirred with demineralized water, stabilized with a non-staining antioxidant, degassed, and dried to constant weight.

[0107] Example 17

[0108] Polymerization and modification.

[0109] In a pre-prepared metal reactor (washed with a solvent containing any alkyl aluminum), 750 ml of a 20 wt% monomer concentration feed (a mixture of hexane and butadiene-1,3) was introduced under stirring. The reactor temperature was adjusted to 0 °C, and a solution of a mixture of 1.5 ml (1.20 mmol) of DIBAH(B), 0.41 ml (0.120 mmol) of gadolinium neodecanoate(A), and 0.4 ml (0.47 mmol) of EADC(C) (chlorine) was continuously introduced. In this case, the molar ratio of the components was A:B:C = 1:10:4, with a butadiene-1,3 / Nd ratio of 15,000 mol / mol. After reaching the desired conversion at 102 °C, a solution of the modifier N-[3-diethoxy(methyl)silyl]propyl]-4-methylpentane-2-amine was added at a rate of 0.03 g / 100 g of polymer. The reactor contents were stirred for 5 minutes. Then, add 0.05 g / 100 g of the polymer as a quick-stopping agent – ​​neodecanoic acid – and stir for another 5 to 15 minutes. Then, remove the reactor, stabilize the polymer with a non-staining antioxidant, degas the polymer, and dry it to constant weight.

[0110] Example 18

[0111] polymerization.

[0112] In a pre-prepared metal reactor (washed with a solvent containing any alkyl aluminum), 750 ml of a feed (a mixture of hexane and isoprene) with a total monomer concentration of 18 wt% was introduced under stirring. The reactor temperature was adjusted to 10 °C, and a solution of 2.72 ml (1.68 mmol) of DIBAH(B), 0.28 ml (0.084 mmol) of neodymium neodecanoate and gadolinium neodecanoate (A), and 0.16 ml (0.19 mmol) of DIBAC(C) was continuously introduced. In this case, the molar ratio of the components was A:B:C = 1:20:2.5, with an isoprene / Nd ratio of 16,000 mol / mol. After reaching the desired conversion, the reactor was removed, the resulting polymer was vigorously stirred with demineralized water, stabilized with a non-staining antioxidant, degassed, and dried to constant weight.

Claims

1. A method for producing cis-1,4-polydiene by polymerization / copolymerization of conjugated dienes in a hydrocarbon solvent in the presence of a catalyst, said catalyst being obtained by mixing a rare earth metal carboxylate (A), an alkyl aluminum (B), and a halogen source (C) in a total molar ratio of components [A]:[B]:[C] = [1]:[5-150]:[1-6], wherein said catalyst is initially prepared in an aliphatic, cycloalkane solvent or a mixture thereof with the conjugated diene, or prepared during polymer synthesis by directly introducing said components into a monomer solution, and wherein the cis-1,4-polydiene polymer is mixed with a modifier and a quick-stopping agent such that the total dosage of said modifier and said quick-stopping agent is from 0 wt% to 1.0 wt% relative to said polymer.

2. The method according to claim 1, wherein neodymium, praseodymium, gadolinium, or mixtures thereof are used as rare earth metals in rare earth metal carboxylates.

3. The method according to claim 1, wherein diisobutylaluminum hydride, triethylaluminum, triisobutylaluminum, isobutylaluminoxane, methylaluminoxane, including modified grades of said methylaluminoxane, or mixtures thereof, are used as alkylaluminum.

4. The method of claim 1, wherein the alkylaluminum in the catalytic system can be introduced at any stage of the preparation of the catalyst, and the aluminum oxane is used as a mixture with standard alkylaluminum, or used alone by introducing the aluminum oxane as a final component in the formation of the complex.

5. The method according to claim 1, wherein ethyl sesquialumina, diethylalumina, ethylalumina, diisobutylalumina, or a mixture thereof is used as the halogen source in the catalytic system.

6. The method according to claim 1, wherein the monomer concentration in the solvent ranges from 10 wt% to 50 wt%, preferably from 15 wt% to 25 wt%.

7. The method according to claim 1, wherein the feed temperature ranges from (-20)°C to 30°C, preferably from (-15)°C to 30°C, and the final temperature of the polymerization process ranges from 70°C to 150°C, preferably from 70°C to 125°C.

8. The method according to claim 1, wherein n-hexane, hexane isomers, cyclohexane, or mixtures thereof are used as the solvent.

9. The method according to claim 1, wherein butadiene-1,3, isoprene, or a mixture thereof is used as the conjugated diene.

10. The method of claim 1, wherein the modifier is selected from a variety of aminosilanes containing alkoxy groups, such as N-(3-triethoxysilylpropyl)cyclohexylamine, 3-triethoxysilyl-N-(1,3-dimethylbutylene)propylamine, N-[3-diethoxy(methyl)silyl]propyl]-4-methylpentan-2-amine, N-[3-dimethoxy(methyl)silyl]propyl]cyclohexylamine, N-(6-aminohexyl)aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, or the modifier is selected from a group of halogen-containing mixtures, such as disulfide dichloride, phosphorus trichloride, phosphorus pentachloride, tin pentachloride, or mixtures thereof.

11. The method of claim 1, wherein neodecanoic acid, stearic acid or lauric acid is used as the quick-stopping agent, and wherein the dose of the quick-stopping agent relative to the polymer is 0 wt% to 0.5 wt%.

12. The method according to claim 1, wherein the feeding sequence of the modifier and the quick-stopping agent can be any of the following: modifier-terminator, modifier-terminator-modifier, terminator-modifier, or modifier without terminator.

13. The method of claim 1, wherein the polymer is mixed with the modifier / terminator in a static mixer and / or mixing reactor as follows: - The monomer conversion rate before feeding the modifier is 60% to 99%, preferably greater than 95%; - The modification time is from 5 minutes to 3 hours; - The modification temperature is 70°C to 150°C, preferably 70°C to 110°C.

14. The method of claim 1, wherein water, preferably demineralized water, is used as the quick-stopping agent, and wherein the dosage of the quick-stopping agent is 1 / 0.1 based on the polymer / water mass ratio.

15. The method of claim 1, wherein the production of cis-1,4-polydiene by polymerization / copolymerization is carried out in a continuous or intermittent mode.

16. The method according to claim 1, wherein the resulting polymer has the following properties: The range of -Mn is 7×10 4 g / mol up to 48×10 4 g / mol; -Mw / Mn ranges from 1.5 to 4.0; -Mounney viscosity (ML1+4, 100°C) is 30 MU to 90 MU; The content of -cis-1,4-chain is at least 95%.

Images