High styrene high vinyl styrene-butadiene rubber with narrow molecular weight distribution and methods for preparation thereof

TECHNICAL FIELD [0001] These recommendations generally apply to high styrene high styrene butadiene rubber (solution-based styrene buttiene rubber (SSBR)), and in particular to high styrene high styrene SSBR with a molecular weight distribution, as well as methods for its preparation.

INFORMATION ABOUT THE PRIOR ART [0002] Production of high styrene high vinyl SSBR is difficult due to the kinetics of the copolymerization process. Usually, polar compounds called randomizers are added to the polymerization system to randomly incorporate styrene.

[0003] The use of some randomizers may lead to a low (less than 10%) content of styrene blocks (> 6 consecutive styrene units) in high vinyl SSBR rubber. A long block of styrene can negatively affect hysteresis, as shown by S. Futamura and G. Day, who observed a 18% tan delta deterioration at 60 ° C when the content of styrene blocks increased from 2% to 7% (Kautschuk Gummi Kunststoffe, 1987, 40, No. 1, 39-43) in a carbon black compound. By comparison, the inclusion of small blocks of styrene can improve abrasion and tensile strength, especially for silica, as described by I. Hattori et al. (143. Meeting of the American Rubber Section of the Society

Chemicals ACS, summer semester 1993, paper No. 22).

[0004] US Patent No. 6,521,712 describes potassium 3,7-dimethyl-3-octylate in the context of the preparation of random low-vinyl soft blocks in block copolymers. Similarly, US Patent No. 6,197,889 describes the use of potassium 3,7-dimethyl-3-octylate as a randomizer. For both patents, the molecular weight of the resulting polymer is very low (in the range of 3000-200.000 g / mol).

[0005] US Patent No. 3,294,768 describes the use of sodium and potassium alkoxides as randomizers for low vinyl SSBR. US Patent No. 3,787,377 describes sodium and potassium tert-amylate and mentholate in the context of continuous anionic polymerization at a temperature of 110 ° C to 125 ° C. US Patent No. 5,916,962 describes a coupled rubber mixture with a broad molecular weight distribution of 1.7 or more after the coupling reaction with silicon tetrachloride.

US Patent No. 5,698,646 describes the process of preparing an elastomer compound after reducing the hysteresis properties, which consisted of the following steps: forming in a hydrocarbon solvent a solution of at least one monomer that can be subjected to anionic polymerization; and polymerization of the above-mentioned monomer with a mixture of lithium dimethylamino-benzylidene-methylamine, t1 potassium amyloxide randomizer and a chelating compound selected from the group consisting of linear oligomeric propane oxanolate and tetramethylethylenediamine to form the polymer. Patent No. EP 2 495 266 A1 discloses a polymer with at least the following characteristics:

(a) content of styrene blocks containing from 4 to 6 styrene units at a level from 27% to 50% by weight relative to the total styrene content in the polymer; (b) a vinyl content of 30% by 80% by weight relative to the total amount of polymerized 1,3-butadiene; and (c) a styrene content of 40% to 70% by weight. based on the total weight of the polymer.

[0006] For some applications, it is desirable to obtain a high styrene high vinyl SSBR rubber having a narrow molecular weight distribution and a specific content of styrene blocks consisting of more than 4 consecutive styrene units.

SUMMARY [0007] The scope of the present invention is defined solely by the appended claims and the statements in this summary do not affect it in any way.

[0008] A polymer in accordance with these recommendations has the following features: (a) a content of styrene blocks containing more than 4 successive styrene units at a level of 40% to 70% by weight. relative to the total styrene content in the polymer; (b) a vinyl content of 25% to 80% by weight relative to the total amount of polymerized 1,3-butadiene; (c) a styrene content of 20% to 75% by weight based on the total weight of the polymer; and (d) a molecular weight distribution D (Mw / Mn) value of 1.5 or less.

[0009] The polymerization process of a polymer consisting of monomer units obtained from styrene monomer and 1,3-butadiene monomer, which complies with these recommendations, takes into account the polymerization of monomer units in the presence of initiator, potassium alkoxide and polar compound. The polar compound consists of structure I.

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[0010] wherein R¹ and R² are independent alkyl groups and R³, R⁴, R⁵, R⁶, R⁷ and R⁸ have been independently selected from the group consisting of alkyl and hydrogen.

DETAILED DESCRIPTION [0011] The inventors have found surprising and unexpected results: high styrene high vinyl SSBR with a narrow molecular weight distribution, the inclusion of styrene in blocks consisting of more than 4 consecutive styrene units, representing 40% to 70% of the total mass, and other features and the phenomena described below.

[0012] Furthermore, the inventors have come to a surprising and unexpected conclusion, namely that the above-mentioned high-styrene high vinyl SSBR rubber can be prepared with the aid of an initiator (e.g. lithium butyl) and a randomizer (e.g. ditetrahydrofurylpropane, also known as 2,2-di (2-oxolanyl) propane or DOP) in combination with potassium alkoxide, in some embodiments, under the following conditions: styrene content&gt; 20% by weight, molar ratio of potassium alkoxide / active initiator&gt; 0.05 and polymerization temperature &lt;80 ° C.

[0013] The terms used in this specification and in the appended claims shall be understood in accordance with the following definitions:

[0014] The term "polymer" means any material produced by the polymerization of monomer units. The term "polymer" as used herein includes the terms "homopolymer" (polymer prepared from one type of monomer), "copolymer" (polymer prepared from two different types of monomers) and "interpolymer" (polymer prepared from more than two different types of monomers) ).

[0015] The expression "alkyl" refers to a substituted or unsubstituted straight, branched or cyclic hydrocarbon chain containing preferably from 1 to 20 carbon atoms. Representative examples of unsubstituted alkyl groups used in accordance with these recommendations are, inter alia, methyl, ethyl, propyl, isopropyl, cyclopropyl, butyl, isobutyl, tert-butyl, sec-butyl, cyclobutyl and similar compounds.

[0016] The term "process" used in reference to the polymerization reaction includes continuous polymerization processes in series and / or semi-series.

[0017] The expression "series" or "semi-series" used in reference to polymerization means polymerization in which more than 60% of the solvent has been fed into the reactor together with additional polymerization components before starting the polymerization by feeding the initiator. The monomer can be administered completely before the initiator is added, partly before the initiator is added, partly after the initiator is added, or completely continuously for a limited time after the initiator is added.

[0018] The expression "continuous polymerization" means a polymerization process in which the solvent, monomer (s) and any additional polymerization components are fed into the reactor in a continuous manner in defined volume ratios. In some embodiments, at least two polymerization reactors connected in series are used. In some embodiments, the reagents are fed to only one reactor.

[0019] The expression "vinyl content" means the percentage by mass (or weight) of butadiene incorporated in the polymer chain at position 1,2, relative to the portion of butadiene (total amount of polymerized butadiene) contained in the polymer.

[0020] The expression "styrene content" means the percentage by mass (or weight) of styrene present in the polymer relative to the total weight of the polymer.

[0021] The expression "content of styrene blocks" means a fraction of the mass of styrene included in the continuous sequences of styrene units relative to the total amount of polymerized styrene in the polymer.

[0022] The term "mixture" means a mixture of substances, including polymeric material and optionally reaction and / or decomposition products formed from polymeric material.

[0023] The term "active initiator" (nBL, pm) means the number of moles of initiator (e.g., organolithium compound) that participates in the polymerization reaction and is not inactivated by impurities contained in the reaction medium. The term "excess initiator" (nBL, exc) means the number of moles of initiator that is used to deactivate contaminants in the system.

[0024] The expression "total amount of monomer fed" means the total amount of styrene and butadiene, expressed in g / min, fed to the continuous polymerization reactor and usually to the first continuous polymerization reactor.

[0025] The expression "total monomer conversion" means the final monomer conversion (e.g., the total sum of styrene and butadiene conversion) determined for the last polymerization reactor and / or at the end of the polymerization reaction.

[0026] A polymer in accordance with these recommendations has the following features: (a) a content of styrene blocks containing more than 4 successive styrene units at a level of 40% to 70% by weight. relative to the total styrene content in the polymer; (b) a vinyl content of 25% to 80% by weight relative to the total amount of polymerized 1,3-diene (preferably 1,3-butadiene); (c) styrene content from

20% to 75% by weight based on the total weight of the polymer; and (d) a molecular weight distribution value of 1.5 or less, wherein the weight average molecular weight (Mw) of the polymer is at least 250,000 g / mol.

[0027] In some embodiments, according to these recommendations, the content of styrene blocks with 6 consecutive styrene units in the polymer is from 5% to 30% by weight, preferably from 19% to 26% by weight, relative to the total content of styrene in polymer.

[0028] In some embodiments in accordance with these recommendations, the total styrene content of the polymer is from 25% to 65% by weight, and in other embodiments from 50% to 60% by weight.

[0029] In some embodiments, the production of polymers takes place in series, and in other embodiments, the production is continuous. According to these recommendations, it is preferable to use series production. In accordance with these recommendations, the molecular weight distribution (Mw / Mn) of the polymer is 1.5 or less, e.g. in the range from 1.05 to 1.5 or 1.05 to 1.4. In some embodiments, the molecular weight distribution is in the range of 1.1 to 1.4. In some embodiments, the molecular weight distribution is in the range of 1.2 to 1.35.

[0030] In certain embodiments of the present invention, the number average molecular weight of the polymer is at least 200,000 g / mol. In some embodiments, the number average molecular weight is greater than or equal to

400 000 g / mol. In some embodiments, the number average molecular weight is greater than or equal to 550,000 g / mol.

[0031] In some embodiments, according to these recommendations, the weight average polymer weight of the polymer is at least 250,000 g / mol, preferably at least 300,000 g / mol. In some embodiments, the weight average molecular weight is greater than or equal to 500,000 g / mol. In some embodiments, the weight average molecular weight is greater than or equal to 600,000 g / mol.

[0032] All the embodiments described above are to be understood as the information provided in any combination, including combinations of embodiments preferred in accordance with these recommendations.

[0033] The polymerization process of a polymer consisting of monomer units formed from

<img file="PL2537872T3_D0002.tif" />

styrene and 1,3-diene monomer, preferably 1,3-butadiene monomer according to these recommendations consists in the polymerization of monomer units in the presence of an initiator, potassium alkoxide and a polar compound, the polar compound having structure I.

[0034] In some embodiments, R¹ and R² are independent alkyl groups. In some embodiments, R¹ and R² are independent C 1 -C 4 alkyl groups. In some embodiments, R¹ and R² are methyl.

[0035] In some embodiments, R³, R⁴, R⁵, R⁶, R⁷ and R⁸ have been independently selected from the group consisting of alkyl and hydrogen. In some embodiments, R³, R⁴, R⁵, R⁶, R⁷ and R⁸ have been independently selected from the group consisting of hydrogen and a C1-C4 alkyl group. In some embodiments, R³, R⁴, R⁵, R⁶, R⁷ and R⁸ were independently selected from the group consisting of hydrogen and methyl. In some embodiments, R³, R⁴, R⁵, R⁶, R⁷ and R⁸ they are hydrogen. In some embodiments, the polar compound consists of ditetrahydrofurylpropane.

[0036] In some embodiments, the molar ratio of polar compound to active initiator is greater than 0.1. In some embodiments, the molar ratio of polar compound to active initiator ranges from 0.2 to

3.

[0037] In some embodiments, the styrene content of the monomer mixture added during polymerization is more than 40 wt. based on the total weight of monomers added.

[0038] In some embodiments, according to these recommendations, the polymerization temperature is less than 80 ° C. In some embodiments in accordance with these recommendations, the polymerization temperature is in the range of 10 ° C to 80 ° C, preferably in the range of 20 ° C and 75 ° C.

[0039] The initiators recommended for use in accordance with these recommendations include those suitable for anionic polymerization. In some embodiments, the initiator used is an organolithium compound (e.g., lithium alkylide) in accordance with these instructions. Representative examples of alkyl lithium compounds for use in accordance with these recommendations are, inter alia, n-lithium butyl, sec-lithium butyl, tert6 lithium butyl, n-lithium pentylex and similar compounds or combinations thereof. In some embodiments, the initiator consists of lithium n-butyl.

[0040] In some embodiments, the degree of total monomer conversion is more than 96 wt. based on the total amount of monomer administered, in some embodiments, the degree of total monomer conversion is greater than 98% by weight, and in other embodiments, the degree of total monomer conversion is greater than 99% by weight.

[0041] In some embodiments, according to these recommendations, the vinyl content of the polymer is from 25% to 80% by weight. based on the total amount of polymerized 1,3-butadiene. In some embodiments, the vinyl content is in the range of 40% to 75% by weight.

[0042] In some embodiments of the process according to these recommendations, potassium alkoxide consists of potassium 3,7-dimethyl-3-octylate.

[0043] In some embodiments of the process according to these recommendations, the molar ratio of polar compound and potassium alkoxide ranges from 30: 1 to

1: 5. In some embodiments, the molar ratio of polar compound and potassium alkoxide is in the range of 15: 1 to 1: 1.5, and / or the molar ratio of the polar compound and active initiator is in the range of 0.1 to 3, preferably from 0, 2 to 1.5.

[0044] According to these recommendations, the process allows the preparation of the polymer in accordance with the method described herein.

[0045] It is preferred that the polymerization according to these recommendations takes place in solvents. Hydrocarbon solvents are currently the preferred solvents. In some embodiments, the solvent used for polymerization consists of an alkane. In some embodiments, the solvent used for polymerization consists of cyclohexane. In some embodiments, the solvent used for polymerization consists of a mixture of cyclohexane and at least one additional alkane.

[0046] According to these recommendations, the process of forming the polymer proceeds according to the type of process described herein.

[0047] In some embodiments, chemical modification of the living polymer by chain end modification and / or coupling reactions may be performed according to the present recommendations. The selection of a suitable chain end modifier and / or coupling agent is based on the intended use and filler.

Representative coupling agents include tin tetrachloride, silicon tetrachloride, divinylbenzene, alkoxysilanes and similar compounds or combinations thereof.

[0048] Representative modifying agents include, but are not limited to, amines, amides, thioglycols, silicon alkoxylates, silane sulfide modifiers, sulfonyl halides as described in European Patent Document No. EP1016674, benzophenone, isocyanate, hydroxyl mercaptans as described in European Patent Document No. EP0464478, acrylamides as described in European Patent Document EP0334042 and similar compounds or combinations thereof. Additional modifiers include amines, amides, imides and nitriles as described in European Patent Documents EP548799, EP510410, EP451604 and EP180141 and in US Patent No. 4,412,041. In some embodiments, silanes, including Epoxy-containing silanes are used to modify the polymer chain end for use in silica filler as described, among others in European Patent Documents No. EP-A-299074, EP-A-102045, EP0447066 and EP0692493. Additional representative modifiers and / or patent information relating to such modifiers are found in International Patent Document No. WO 2009/134665.

[0049] According to these recommendations, the mixture comprises a polymer of the type described herein. In some embodiments in accordance with these instructions, the mixture includes additives, e.g. oil. In some embodiments in accordance with these recommendations, the mixture contains oil in an amount of 5% to 40% by weight. based on the weight of the polymer. In some embodiments in accordance with these instructions, the mixture does not contain oil.

[0050] In some embodiments in accordance with these recommendations, the mixture comprises a polymer of the type described herein and at least one additive. In some embodiments, the polymer is combined and / or reacted with at least one filler, vulcanizing agent and / or optionally at least one additive, which may be, inter alia, accelerator, coupling agents, unmodified non-crosslinked elastomers (i.e. conventional non-crosslinked elastomers which did not react with the modifier but which were prepared and interrupted), as well as similar compounds or combinations thereof.

[0051] In some embodiments, according to these recommendations, the mixture contains at least one filler that serves as a reinforcing agent. Examples of suitable fillers include carbon black, silica, two-phase carbon silicate filler, clay, calcium carbonate, magnesium carbonate and similar compounds or combinations thereof. In some embodiments, combinations of carbon black and silica, carbon-silica two-phase fillers, or combinations of carbon-silica two-phase filler and carbon black and / or silica are used.

[0052] In some embodiments, the carbon black is produced by means of an oven, where the specific surface area for nitrogen adsorption for carbon black is from 50 to 200 m²/ g, and the DBP oil absorption value is 80 to 200 ml / 100 g (e.g. carbon black, FEF, HAF, ISAF or SAF). In some embodiments, high agglomeration carbon black is used. In some embodiments, carbon black or silica is added in an amount of 2 to 100 parts by weight per 100 parts by weight of all polymer. In some embodiments, carbon black or silica is added in an amount of from 5 to 100 parts by weight. In some embodiments, carbon black or silica is added in an amount of from 10 to 100 parts by weight. In some embodiments, carbon black or silica is added in an amount of from 10 to 95 parts by weight.

[0053] According to these recommendations, the product consists of at least one element formed from such a mixture. In some embodiments, the product is a tire. In some embodiments, the product is a shoe element.

[0054] The following examples and representative procedures show the characteristics according to these recommendations and serve only as examples. They do not limit the scope of the attached patent claims or their equivalents.

EXAMPLES [0055] The degree of monomer conversion was determined by measuring the concentration of solids in the polymer solution at the end of the polymerization process. The maximum solids content is obtained by converting 100 wt. of charged butadiene (mBd) and styrene (mSt) to the final polymer according to the TSC formula max = (mBd + mSt) / (mBd + mSt + m polar compound + mBL + mcyclohexane) * 100%. A sample of the polymer solution weighing from 1 g to 10 g, depending on the expected monomer conversion, was taken from the reactor directly into a 200 ml Erlenmeyer flask filled with ethanol (50 ml). The weight of the filled Erlenmeyer flask was determined before sampling ("A") and after sampling ("B"). The precipitated polymer was separated from the ethanol by filtration using a weighted paper filter (glass microfiber paper with a diameter of 90 mm, from MUNKTELL, class "C" weight), dried at 140 ° C using a HR73 moisture analyzer (from MettlerToledo) until a constant weight is achieved. Criterion No. 5 was used. Finally, a second drying phase was carried out using the exclusion criterion No. 4 to achieve the final weight "D" of the dry sample on the paper filter. The polymer content of the sample was calculated according to the formula: TSC = (DC) / (BA) * 100%. The final monomer conversion value was calculated according to the formula TSC / TSC max * 100%.

[0056] The molecular weight and the molecular weight distribution of the polymer were measured by size exclusion chromatography (SEC) based on polystyrene standards. Each polymer sample (9-11 mg) was dissolved in tetrahydrofuran (10 mL) to form a solution. The solution was filtered using a 0.45 μm filter. A sample of 100 pl was added to the GPC column (Hewlett Packard 1100 system with 3 PLgel 10 μm MIXED-B columns at 40 ° C). Refractometric detection was used for molecular weight analysis. Molecular mass was calculated as for polystyrene based on calibration based on EasiCal PS1 polystyrene standards (Easy A and B) from Polymer Laboratories. The number average molecular weight (Mn) and the weight average molecular weight (Mw) are given based on polystyrene standards. The molecular weight distribution is expressed in the form of polydispersity D = Mw / Mn.

[0057] The vinyl content and total styrene content were measured by Ή NMR spectroscopy in accordance with ISO 21561-2005 using an NMR spectrometer

Avance 400 MHz from BRUKER and 5 mm dual probe. CDCl3 / TMS was used as the solvent in a weight ratio of 0.05%: 99.95%. The content of styrene blocks consisting of more than 6 consecutive styrene units was determined based on the method described by Y. Tanaka et al. in Rubber Chemistry and Technology, 1981, 54, No. 4, pp. 685-691 based on the chemical shift value of the proton ortho resonant signal of the phenyl group (Ph) higher than 6.7 ppm. The content of styrene blocks consisting of at least 4 successive styrene units was determined on the basis of the method described in German Patent Document DE69712962 based on the chemical shift value of the resonant signal of the orthon proton of the phenyl group (Ph) in the range from 6.94 to 6 ppm. The content of styrene blocks consisting of 4 to 6 consecutive units was calculated on the basis of the difference between the two above contents of styrene blocks.

[0058] COMPARATIVE EXAMPLE 1 (use of potassium 3,7-dimethyl-3-octylate (hereinafter KDMO or K) (50% in hexanes) [0059] 5,376.55 g of dried cyclohexane was fed into a vented and nitrogen-flushed reactor with a 10-liter reactor stainless steel. 326.17 g of 1,3-butadiene, 403.73 g of styrene and 0.083 mmol of potassium 3,7-dimethyl-3-octylate (50% in heptane) were fed to the reactor (K / active lithium butyl mol / mol = 0.076) The mixture was mixed and heated to 50 ° C. Impurities in the system were titrated by the gradual addition of lithium butyl. After endpoint recognition, the polymerization process was started by adding 1.466 mmol of lithium n-butyl (15% solution in cyclohexane) with a pump within 1 minute and 19 seconds. Then the polymerization process began. The temperature in the reactor increased to 65C in 30 minutes. The reaction was terminated after 200 minutes by adding methanol - a stopping agent. The Irganox 1520 antioxidant has been added.

[0060] A sample was taken with a stopcock and needle test tube to determine solids content. The measured degree of conversion was 99.57%.

[0061] The resulting polymer was analyzed by GPC: Mn = 533 636, Mw = 674 699, D = 1.264. The microstructure and content of styrene blocks was measured by 1H NMR spectroscopy. The following results were obtained: styrene = 55.2%, vinyl (1,2-polybutadiene, calculated on the basis of butadiene fraction) = 12.3%, styrene blocks with more than 4 styrene units = 82% and styrene blocks with more than 6 units styrene = 39%.

[0062] COMPARATIVE EXAMPLE 2 (use of potassium 3,7-dimethyl-3-octylate (50% in hexanes) [0063] 5309.09 g of dried cyclohexane was introduced into a vented and nitrogen purged 10-liter stainless steel reactor. 325.38 g of 1,3-butadiene, 398.27 g of styrene and 0.5011 mmol of potassium 3,7-dimethyl-3-octylate (50% in heptane) was fed to the reactor (K / active lithium butyl mol / mol = 0.38) .

[0064] The mixture was mixed and heated to 50 ° C. Impurities in the system were titrated by the gradual addition of lithium butyl. After recognition of the endpoint, the polymerization process was started by adding 1.236 mmol of lithium n-butyl (15% solution in cyclohexane) with a pump within 1 minute and 50 seconds.

Then the polymerization process began. The temperature in the reactor increased to 65C in 30 minutes. The reaction was terminated after 144 minutes by adding methanol - the stopping agent. The Irganox 1520 antioxidant has been added.

[0065] A sample was taken with a stopcock and needle test tube to determine solids content. The measured degree of conversion was 99.18%.

[0066] The resulting polymer was analyzed by GPC: Mn = 510 436, Mw = 830 705, D =

1,627. The microstructure and content of styrene blocks was measured by 1H spectroscopy

NMR. The following results were obtained: styrene = 50.3%, vinyl (1,2-polybutadiene, calculated on the basis of butadiene fraction) = 24.3%, styrene blocks with more than 4 styrene units =

64% and styrene blocks with more than 6 styrene units = 20%.

[0067] EXAMPLE 1 (use of potassium 3,7-dimethyl-3-octylate (50% in hexanes) / ditetrahydrofurylpropane (DOP).

[0068] 5302.55 g of dried cyclohexane was introduced into a deaerated and purged with a 10 liter stainless steel reactor. 324.98 g of 1,3-butadiene,

400.62 g styrene and 0.5051 mmol potassium 3,7-dimethyl-3-octylate (50% in heptane) and

0.4807 mmol of ditetrahydrofurylpropane (DOP) was fed to the reactor (K / active lithium butyl butyl mol / mol = 0.359, DOP / active lithium butyl butyl 0.341). The mixture was mixed and heated to 50 ° C. Impurities in the system were titrated by the gradual addition of lithium butyl. After the endpoint recognition, the polymerization process was started by adding 1.4086 mmol of lithium n-butyl (15% solution in cyclohexane) with a pump within 1 minute and 33 seconds. Then the polymerization process began. The temperature in the reactor increased to 65 ° C in 30 minutes. The reaction was terminated after 200 minutes by adding methanol - a stopping agent. The Irganox 1520 antioxidant was added. A sample was taken using a stopcock and needle test tube to determine solids content. The measured degree of conversion was 99.11%. The resulting polymer was analyzed by GPC: Mn = 502 096, Mw = 742 517, D = 1.479. The microstructure and content of styrene blocks were measured by Ή NMR spectroscopy. The following results were obtained: styrene = 55.5%, vinyl (1,2-polybutadiene, calculated on the basis of butadiene fraction) = 40%, styrene blocks with more than 4 styrene units = 70% and styrene blocks with more than 6 styrene units = 24%.

[0069] EXAMPLE 2 (use of potassium 3,7-dimethyl-3-octylate (50% in hexanes) / ditetrahydrofurylpropane (DOP) [0070] 5309.09 g of dried cyclohexane was fed to a vented and nitrogen-flushed 10-liter stainless steel reactor . 325.38 g of 1,3-butadiene,

398.27 g styrene, 0.1265 mmol potassium 3,7-dimethyl-3-octylate (50% in heptane) and 0.4807 mmol ditetrahydrofurylpropane (DOP) are fed into the reactor (K / active lithium butyl but mol / mol = 0, 1, DOP / active lithium butyl butyl mol / mol = 0.398). The mixture was mixed and heated to 50 ° C. Impurities in the system were titrated by the gradual addition of lithium butyl. After recognition of the endpoint, the polymerization process was started by adding 1.2366 mmol of lithium n-butyl (15% solution in cyclohexane) using a pump within 1 minute and 50 seconds. Then the polymerization process began. The temperature in the reactor increased to 65 ° C in 30 minutes. The reaction was terminated after 120 minutes by adding methanol, a stopping agent. The Irganox 1520 antioxidant has been added. A sample was taken with a stopcock and needle test tube to determine solids content. The measured degree of conversion was 99.18%. The resulting polymer was analyzed by GPC: Mn = 606 718, Mw = 810 367, D = 1.336. The microstructure and content of styrene blocks were measured by Ή NMR spectroscopy. The following results were obtained: styrene = 54.4%, vinyl (1,2-polybutadiene, calculated on the basis of butadiene fraction) = 37.6%, styrene blocks with more than 4 styrene units = 70% and styrene blocks with more than 6 units styrene = 24%.

[0071] EXAMPLE 3 (use of potassium 3,7-dimethyl-3-octylate (50% in hexanes) / ditetrahydrofurylpropane (DOP).

[0072] 5,241.71 g of dried cyclohexane was introduced into a deaerated and purged with a 10 liter stainless steel reactor. 321.48 g of 1,3-butadiene, 398.25 g of styrene and 0.1198 mmol of potassium 3,7-dimethyl-3-octylate (50% in heptane) and 1.1846 mmol of ditetrahydrofurylpropane (DOP) are fed into the reactor (K / active lithium butyl mol / mol = 0087, DOP / active lithium butyl mol / mol = 0.894). The mixture was mixed and heated to 50 ° C. Impurities in the system were titrated by the gradual addition of lithium butyl. After recognition of the endpoint, the polymerization process was started by adding 1.3816 mmol of lithium n-butyl (15% solution in cyclohexane) with a pump within 1 minute and 50 seconds. Then the polymerization process began. The temperature in the reactor increased to 65 ° C in 30 minutes. The reaction was terminated after 120 minutes by adding methanol, a stopping agent. The Irganox 1520 antioxidant was added. A sample was taken using a stopcock and needle test tube to determine solids content. The measured degree of conversion was 99.58%. The resulting polymer was analyzed by GPC: Mn = 557 928, Mw =

722 762, D = 1.246. The microstructure and content of styrene blocks were measured by Ή NMR spectroscopy. The following results were obtained: styrene = 54.5%, vinyl (1.2polybutadiene, calculated on the basis of butadiene fraction) = 52%, styrene blocks with more than 4 styrene units = 66% and styrene blocks with more than 6 styrene units = 20% .

[0073] EXAMPLE 4 (use of potassium 3,7-dimethyl-3-octylate (50% in hexanes) / ditetrahydrofurylpropane (DOP).

[0074] 5,344.73 g of dried cyclohexane was introduced into a deaerated and purged with a 10 liter stainless steel reactor. 327.57 g of 1,3-butadiene, 401.18 g of styrene and 0.1222 mmol of potassium 3,7-dimethyl-3-octylate (50% in heptane) and 3.531 mmol of ditetrahydrofurylpropane (DOP) are fed into the reactor (K / active lithium butyl mol / mol = 0.102, DOP / active lithium butyl mol / mol = 2.948). The mixture was mixed and heated to 50 ° C. Impurities in the system were titrated by the gradual addition of lithium butyl. After recognition of the endpoint, the polymerization process was started by adding 1.1978 mmol of lithium n-butyl (15% solution in cyclohexane) with a pump within 1 minute and 46 seconds. Then the polymerization process began. The temperature in the reactor increased to 65 ° C in 30 minutes. The reaction was terminated after 200 minutes by adding methanol - a stopping agent. The Irganox 1520 antioxidant was added. A sample was taken using a stopcock and needle test tube to determine solids content. The measured degree of conversion was 99.13%. The resulting polymer was analyzed by GPC: Mn = 659 095, Mw = 859 095, D = 1.274. The microstructure and content of styrene blocks were measured by Ή NMR spectroscopy. The following results were obtained: styrene = 55.1%, vinyl (1,2-polybutadiene, calculated on the basis of butadiene fraction) = 63.9%, styrene blocks with more than 4 styrene units = 66% and styrene blocks with more than 6 units styrene = 19%.

[0075] EXAMPLE 5 (use of potassium 3,7-dimethyl-3-octylate (50% in hexanes) / ditetrahydrofurylpropane (DOP).

[0076] 5417 g of dried cyclohexane was introduced into a deaerated and purged with a 10 liter stainless steel reactor. 302.28 g 1,3-butadiene, 371 g styrene and 0.112 mmol potassium 3,7-dimethyl-3-octylate (50% in heptane) and 1.14 mmol ditetrahydrofurylpropane (DOP) were fed into the reactor (K / active lithium butyl mol / mol = 0.105, DOP / active lithium butyl butyl (mol / mol = 0.067). The mixture was mixed and heated to 70 ° C. Impurities in the system were titrated by the gradual addition of lithium butyl. After recognition of the endpoint, the polymerization process was started by adding 1.07 mmol of lithium n-butyl (15% solution in cyclohexane) with a pump within 30 seconds. Then the polymerization process began. The temperature in the reactor was constantly maintained at 70 ° C. The reaction was terminated after 120 minutes by adding methanol, a stopping agent. The Irganox 1520 antioxidant has been added. A sample was taken with a stopcock and needle test tube to determine solids content. The measured degree of conversion was 98.88%. The resulting polymer was analyzed by GPC: Mn = 673 082, Mw = 880 826, D = 1.308. The microstructure and content of styrene blocks were measured by Ή NMR spectroscopy. The following results were obtained: styrene = 55.6%, vinyl (1,2-polybutadiene, calculated on the basis of butadiene fraction) = 42.6%, styrene blocks with more than 4 styrene units = 53% and styrene blocks with more than 6 units styrene = 10%.

[0077] EXAMPLE 6 (use of potassium 3,7-dimethyl-3-octylate (50% in hexanes) / ditetrahydrofurylpropane (DOP).

[0078] 5387 g of dried cyclohexane was introduced into a deaerated and purged with a 10 liter stainless steel reactor. 400.52 g of 1,3-butadiene, 268 g of styrene and 0.111 mmol of potassium 3,7-dimethyl-3-octylate (50% in heptane) and 1.117 mmol of ditetrahydrofurylpropane (DOP) are fed into the reactor (K / active lithium mol butyl / mol = 0.089, DOP / active lithium butyl butyl (mol / mol = 0.889). The mixture was mixed and heated to 70 ° C. Impurities in the system were titrated by the gradual addition of lithium butyl. After recognition of the endpoint, the polymerization process was started by adding 1.26 mmol of lithium n-butyl (15% solution in cyclohexane) with a pump within 30 seconds. Then the polymerization process began. The temperature in the reactor was constantly maintained at 70 ° C. The reaction was terminated after 90 minutes by adding methanol, a stopping agent. The Irganox 1520 antioxidant has been added. A sample was taken with a stopcock and needle test tube to determine solids content. The measured conversion rate was 99.95%. The resulting polymer was analyzed by GPC: Mn = 606 718, Mw = 761 935, D = 1.256. The microstructure and content of styrene blocks were measured by Ή NMR spectroscopy. The following results were obtained: styrene = 40.7%, vinyl (1,2-polybutadiene, calculated on the basis of butadiene fraction) = 40%, styrene blocks with more than 4 styrene units = 43% and styrene blocks with more than 6 styrene units = 7%.

[0079] EXAMPLE 7 (use of potassium 3,7-dimethyl-3-octylate (50% in hexanes) / ditetrahydrofurylpropane (DOP).

[0080] 18787 g of dried cyclohexane was introduced into a deaerated and purged with a 40 liter stainless steel reactor. 2,343 g of 1,3-butadiene, 929.56 g of styrene and 1.693 mmol of potassium 3,7-dimethyl-3-octylate (50% in heptane) and 3.394 mmol of ditetrahydrofurylpropane (DOP) are fed into the reactor (K / active lithium mol butyl / mol = 0 096, DOP / active lithium butyl butyl (mol / mol = 0.192). The mixture was mixed and heated to 65 ° C. Impurities in the system were titrated by the gradual addition of lithium butyl. After recognition of the endpoint, the polymerization process was started by adding 17.6 mmol of lithium n-butyl (15% solution in cyclohexane) using nitrogen overpressure within 5 seconds. Then the polymerization process began. The temperature in the reactor was constantly maintained at 65 ° C. The reaction was terminated after 60 minutes by adding methanol - a stopping agent. The Irganox 1520 antioxidant was added. A sample was taken using a stopcock and needle test tube to determine solids content. The measured degree of conversion was 99.67%. The resulting polymer was analyzed by GPC: Mn = 252 670, Mw = 275 487, D = 1.09. The microstructure and content of styrene blocks was measured by 1H NMR spectroscopy. The following results were obtained: styrene = 28%, vinyl (1,2-polybutadiene, calculated on the basis of butadiene fraction) = 28.9%, styrene blocks with more than 4 styrene units = 45% and styrene blocks with more than 6 styrene units = 10%.

[0081] The examples and comparative examples show that these recommendations allow the preparation of a styrene butadiene copolymer with a specified target styrene content with more than 4 consecutive styrene units in combination with a generally high styrene content, selected vinyl content and a narrow molecular weight distribution. By using the process in accordance with these recommendations, polymers obtained through the novel and ingenious methods described herein can be polymerized using standard high-performance polymerization techniques. All polymer properties outlined herein are properties prior to subsequent modifications, e.g., deactivation (so-called "end-capping"), coupling, etc., as described above. By developing these recommendations for the preparation of polymers with a narrow molecular weight distribution, a large number of living chain ends can be obtained in the last phase of the polymerization process, which allows uniform modification of the chain ends.

[0082] The content of each patent and non-patent document mentioned above is incorporated herein by reference, except in cases where the information or definitions provided therein are inconsistent with the content of this document - in such cases the information and definitions given herein are paramount. document.

[0083] The detailed descriptions listed above are given as explanations and examples, and their use does not limit the scope of the appended claims. Alternate versions of the examples set forth in the preferred embodiments contained herein will be apparent to those skilled in the art and remain within the scope of the appended claims and their equivalents.