Bimodal neodym-catalysed polybutadien

The present invention relates to a neodymium-catalyzed high molecular weight bimodal polybutadiene with a high proportion of cis-1,4 units of> 95% and a small proportion of vinyl units <1%, a method for its manufacture and use.

[0002] Polybutadienes are used as important components of rubber mixtures / rubber compounds in the tire industry, whereby improved end properties, such as reduced rolling friction resistance and abrasion, are needed. A further area of ​​use are golf ball cores or soles for shoes, with great resilience here.

[0003] Polybutadienes with a high proportion of cis-1,4 units have been produced for a long time on a large technical scale and are used to manufacture tires and other rubber products and to modify the impact strength of polystyrene.

[0004] For the production of large proportions of cis-1,4 units, rare earth catalysts are currently almost exclusively used and are described, for example, in EP-A1 0 011 184 and EP-B-A1 0 007 027. [0005] It is known of the state of the art that special neodymium-catalyzed polybutadienes, from the group with a high content of cis-polybutadiene, show particularly favorable properties regarding rolling resistance, abrasion and resilience.

[0006] It is known to those skilled in the art that single site catalysts based on rare earth allyl complexes with a specific structure are used to prepare polybutadienes, as are for example described in Macromolecular Chemistry and Physics, 2002 (203/7) 1029-1039.

[0007] The catalyst systems used play an important role in the production of polybutadienes.

[0008] The technically used neodymium catalyst is, for example, the Ziegler-Natta system, which is formed of many catalyst components. During the formation of a catalyst, various centers are usually formed in the catalyst, which are recognizable in the polymer on the basis of at least a bimodal molar mass distribution. In the Ziegler-Natta catalyst system, 3 known catalyst components, most often consisting of a neodymium source, a chloride source and an organo aluminum compound, are mixed in different ways and under certain temperature conditions, the catalyst system being prepared for polymerization with or without aging.

[0009] Many methods are known in the art for making Ziegler-Natta catalyst systems that are used to make polybutadienes.

[0010] EP 0 375 421 B1 describes a method of producing a catalyst for the polymerization of butadiene, whereby an aluminum compound with hydrocarbon groups or an aluminum compound with hydrocarbon groups and hydrogen, neodymium neodecanoate or neodymium naphthenate and a source of halide in hydrocarbon solution (hexane) are mixed at temperature from -15 ° C to -60 ° C, wherein the catalyst system is aged for at least 8 hours before being used for polymerization. Aging is preferably carried out at -20 ° C.

[0011] The number of chain ends in the polymer is responsible for the energy dissipation. The greater the number of free chain ends, the greater the energy dissipation of the polymer. However, the lower the energy dissipation of the polymer, the lower the rolling resistance, for example, and the better the resilience of the polymer. Therefore, the final properties of the linear polymer, only with 2 tips

EP2536769 B1

V9788PL00 / TS chain in the molecule are always better than the properties of a branched polymer with the same molar mass.

[0012] CoBR and NiBR polymers are also known in the art; they are statistically more branched than linear NdBR polymers, as exemplified in Tire Technology International (2009), 82-86 and Journal of Macromolecular Science, Pure and Applied Chemistry (2004), A41 (3), 245-256.

[0013] The benefits of linear NdBR consist, in particular, of improved dynamic properties and less energy absorption, which, among other things, when applied to tires leads to less rolling resistance and, when applied to golf balls, to improved resilience. In US 6,706,814 B2 it is described that by using linear polybutadiene, for example in PSHI (modified impact polystyrene) fittings, impact resistance is improved.

[0014] On the other hand, however, it is known that linear rubbers show high solution viscosities, whereby high solution viscosities also forcefully lead to high processing viscosities in the ABS or PS-HI process. Furthermore, it is known that the dissolution time depends on the degree of branching, with linear polymers dissolving much more slowly than branched polymers. Due to higher processing viscosities and longer dissolution times, the profitability of using linear polybutadienes strongly decreases.

[0015] In addition, branching is known to be particularly important for polymerability. When using branched polymers for ABS or PS-HI, the branched polymers improve dissolution properties and reduce dissolution time. The molar mass and the degree of branching of the polymer determine the viscosity of the solution.

[0016] NdBRi polymers neodymium-catalyzed polybutadienes are understood as synonyms.

[0017] It is therefore necessary to make available neodymium-catalysed polybutadiene which exhibits favorable linearity properties relating to dynamic properties as well as favorable branching properties related to machinability.

[0018] Polybutadiene and polymer are used as synonyms.

[0019] To solve the task, a polybutadiene of the type mentioned at the outset is proposed, which has a linear polymer main fraction and a polymer fraction with long chain branches, where the polymeric main fraction shows an increase> 0.5, and a polymeric fraction with long chains shows an increase of <0.3 in the RGM ratio.

[0020] Fractions are eluted by flow fractionation in an asymmetric flow force field (flow-field-flow) (AF4).

[0021] Preferably, these are polybutadienes which are catalysed by means of neodymium-containing catalyst systems. These types of systems are Ziegler-Natta catalysts based on neodymium compounds that are soluble in hydrocarbons.

[0022] Neodymium carboxylates or neodymium alkoxides are particularly preferably used as the neodymium compound, in particular neodymium neodecanoate, neodymium octoate, neodymium naphthenate, neodymium 2,2 diethylhexanoate and / or neodymium 2,2-diethylheptanoate.

[0023] It was surprisingly clear that the polybutadiene according to the invention shows linearity and branching, and therefore has a combination of both properties.

[0024] In the past, only the size-dependent exclusion chromatography was available for characterizing the structure of polybutadiene chains and for determining the molecular weight distribution and its size.

EP2536769 B1

V9788PL00 / TS particle size (GPC) coupled with light scattering detection and viscosity determination. It has turned out that these methods cannot be satisfactorily characterized by the NdBR rubber according to the invention.

[0025] Therefore, flow fractionation in an asymmetric flow force field (AF-4) was used, which is perfectly suited for characterization. The separation takes place in an empty channel without a stationary phase. Thus, the separation can take place almost without shearing and interaction.

[0026] The structure-property ratios make it possible to describe the relationship between molecular parameters and properties of this polymer.

[0027] The RGM ratio represents the relationship between the macromolecular inertia radius (RMS) and the molar mass M of the macromolecule and is calculated from a double logarithmic plot as the increase in the radius of inertia with the increase in molar mass.

[0028] The radius of inertia of the macromolecule (RMS) is determined by light scattering, wherein the irradiated light is scattered on the polymer bundles. The hydrodynamic volume or the radius of inertia of the polymer macromolecule is determined from the dependence of the scattered light signal angle.

[0029] For linear polymers, the radius of inertia increases in proportion to the molar mass. As described, among others, in the Journal of Applied Polymer Science, 54 (1994) 91-103, linear polymers have a 0.5 to 0.6 increase in the RGM ratio. At the same molar mass, with increasing branching in the polymer, the density of the polymer ball increases and the radius of inertia decreases. The higher the degree of branching of the polymer, the smaller the increase in the RGM ratio. Branched polymers are described as having an increase in the RGM ratio of less than 0.5, with an increase of 0.33 and less indicating highly branched polymers with spherical geometry.

[0030] To determine these parameters, coupled devices were used in the course of the research, consisting of a fractionation unit for flow fractionation in an asymmetrical force field with a scattering photometer at many angles and concentration detectors.

Description of the analysis using AF4:

[0031] Prior to analysis, the polymers were dissolved in THF (tetrahydrofuran) in purity for chromatographic analysis (HPLC). The concentration was 3 mg / ml. 1 mg / ml BHT was added to the stabilization each time. The dissolution time was 16 hours at room temperature, then 4 hours in an oven at 50 ° C, and finally 48 hours at room temperature. Before and after the heat treatment, the polymer solution was stirred by light hand shaking, and no mechanical homogenization was carried out. In order not to remove high molecular polymer particles, filtration was abandoned. The AF-4 channel was equipped with a regenerated cellulose membrane (cut-off value 10 kg / mol PS).

[0032] Molecular weights and concentrations were calculated with an increase in refractive index for polybutadiene of 0.137 ml / mg. All measurements were carried out with the pump system of the AF4 2000 device from Postnova Analytics (Landsberg / Lech, Germany). As a combination of detectors, MALLS-Detector from Dawn DSP, Wyatt Technology (Santa Babara, USA) and RI-Detector PN 3140 from Postnova Analytics (Landsberg / Lech, Germany) were used.

[0033] Figure 1 shows the relationship of the transverse flow gradient used for the AF4 analysis:

The injection volume for AF4 analysis was 100 ml. After the injection phase, the sample was transported at a flow rate of 0.2 ml / min to the channel to avoid possible disintegration

EP2536769 B1

V9788PL00 / TS molecules in a relatively highly concentrated solution. During this procedure, the cross flow was constantly at its maximum. A second flow, so-called focus / focal length, was also active during the injection procedure. This flow ensured a constant flow through the detector of 0.5 ml / min and allowed the injected sample to be kept in a very narrow zone (reduced subsequent bandwidth expansion). After an injection phase of 4 minutes, the focal flow was exponentially reduced to 0 within 1 minute and a cross-flow program followed.

[0034] It could be said that the polymers of the invention consist of two fractions, with the linear main fraction showing an increase> 0.5 and the long-branched polymer fraction showing an increase <0.3 in the RGM ratio.

[0035] Due to the strong branching of the long-branching polymer fraction, the maximum inertia radius of the dissolved polymer macromolecule is reduced, so that the proportion of the polymer with an inertia radius above 100 nm is <15%, preferably <10%, particularly preferably <5%.

[0036] The width of the inertia ray distribution is very narrow and is <45 nm, preferably <40 nm, particularly preferably <35 nm.

[0037] The width of the inertia ray distribution is determined on the basis of differential overlap. The maximum differential value of the radius distribution is divided in half and the width of the radius of inertia distribution is obtained as the difference from both values ​​of the radius of the curve at these numerical quantities.

[0038] Preferably, the polybutadiene of the invention has a long branching polymer fraction of> 1 million g / mol.

[0039] Preferably, the linear polymer main fraction is larger than the long branching polymer fraction.

[0040] A method is available for the production of polybutadiene according to the invention which has the following method steps:

1. a modified catalyst preparation step with the initial formation of a neodymium-based catalyst system consisting of component A: alcoholate, phosphonate, phosphinate and / or phosphate, carboxylate, a complex complex of rare earths with diketones and / or rare earth halide addition compounds with donor compounds oxygen or nitrogen, preferably neodymium and Versatic ™ / Neodymversatat, component B: constituting dialkyl hydrogel, preferably diisobutyl hydrogel (DIBAH), component C: being diene, preferably butadiene or isoprene and component D: at least one organometallic halide, preferably ethyl aluminum sesquide chloride (EASC), wherein components A, B and C are first mixed at a temperature of from -20 ° C to 80 ° C, preferably from 0 ° C to 40 ° C for a first step a time from 5 minutes to 10 hours, preferably 10 minutes to 2 hours and the mixture is then cooled to less than -10 ° C, preferably to less than -30 ° C before adding component D;

EP2536769 B1

V9788PL00 / TS

2. optionally pre-forming the modified catalyst system at a temperature from -30 ° C to 80 ° C, preferably from 5 ° C to 50 ° C for 10 minutes to 250 hours, preferably from 20 minutes to 100 hours;

3. polymerization of monomers at a temperature between -20 and 100 ° C,

4. then, keeping the polymerization solution at the end of the polymerization, namely at a conversion rate> 85%, preferably> 90%, and particularly preferably> 95% butadiene, at a temperature> 100 ° C, preferably 100 ° C to 140 ° C, particularly preferably 100 ° C to 125 ° C for 10 to 120 minutes, preferably for 15 to 60 minutes.

[0041] By carrying out the method of the invention, it was possible to form a neodymium-based catalyst system that exhibits optimal activity and leads to the desired polymer mentioned above. This interaction of the amount and mode of action of the catalyst components determines the final properties of the polymer, as well as the cost-effectiveness of the method of manufacture.

[0042] Preferably component C is the same monomer that is used for the production of neodymium catalyzed high molecular weight polybutadiene. The presence of diene in the production of the catalyst is particularly important because then a stable catalyst can be produced. Hexane, cyclohexane, toluene or a mixture of solvents in the form of the C6 fraction are used as the solvent. Other solvents are also possible.

[0043] The solvent may be added in pure form or as a solvent for the individual catalyst components. The amount of solvent is adjusted to component A, wherein the concentration of component A to solvent is between 0.05 and 0.3 mole / l, preferably between 0.08 and 0.2 mole / l.

[0044] The molar ratio of component A to component B is 1: 1 to 1: 100, preferably 1: 3 to 1:80, and particularly preferably 1: 3 to 1:50. The molar ratio of component A to component C is 1: 1 to 1: 200, preferably 1: 2 to 1: 100, particularly preferably 1: 3 to 1:50. The molar ratio of component A to component D is 1: 0.5 to 1: 20, preferably 1: 0.7 to 1:10, and particularly preferably 1: 0.8 to 1: 8.

[0045] The cooling temperature in step 1 of the modified catalyst production is preferably -10 ° C or -20 ° C, preferably -30 ° C, particularly preferably -60 ° C.

[0046] In addition, it is possible to use trialkylaluminum, preferably tributylaluminum (TIBA) in the preparation of the catalyst system. The molar ratio of component A to trialkylaluminum, preferably tributylaluminum (TIBA) is 1: 0.4 to 1:15, preferably 1: 0.5 to 1: 8.

[0047] After preforming the catalyst system, if this preforming is needed, the polymerization is started by mixing in organic solvents. These solvents must be inert to the catalyst system used. Aromatic, aliphatic and cycloaliphatic hydrocarbons such as benzene, toluene, pentane, n-hexane, isohexane, heptane and cyclohexane are suitable, for example.

[0048] Polymerization can be carried out both continuously and discontinuously. [0049] The polymerization is carried out at a temperature between -20 and 100 ° C. In the usual embodiment, the catalyst consisting of components A, B, C and D, optionally TIBA, is added to a mixture of 100 parts by weight of a solvent containing 5 to 50 parts by weight, preferably 8 to 30 parts by weight. monomer.

[0050] The time saved towards the end of the polymerization is also referred to here as the pot life.

EP2536769 B1

V9788EN00 / TS [0051] The polymer branching reaction above 1 million g / L is protected for a lifetime at a suitable temperature.

[0052] Preferably, the temperature at the end of the polymerization, i.e. during the lifetime is 100 to 140 ° C, preferably 100 to 120 ° C.

[0053] At the end of the pot life, the catalyst is deactivated by the addition of small amounts of water, carboxylic acids or alcohols.

[0054] The polymer solution and polymerization solution are understood as synonyms.

[0055] Normal stabilizers in usual amounts may be added to the polymer solution prior to processing. Phenols or aromatic amines or phosphites with steric obstacles, such as 2,6-di-tert.-butyl-4,5-methyl-phenol, are used as stabilizers.

[0056] Isolation of polymers takes place by evaporation of the polymer solution, by precipitation with a non-solvent, such as, for example, methanol, ethanol, acetone, or preferably by distillation of the solvent with steam.

[0057] After steam stripping, water is removed by means of suitable screen or screw aggregates, such as a screw press, or expansion screws or fluidized bed dryers.

[0058] Drying takes place by the usual method, eg, in a chamber dryer or a screw dryer.

[0059] In addition, the polybutadienes of the invention alone, in a mixture with aromatic or aliphatic oils, or in a mixture with other rubbers can be used in the production of rubber mixtures / rubber mixtures and rubber vulcanizates, which are used, for example, in the tire industry or in the manufacture of rubber soles or technical rubber products. Synthetic rubbers are also suitable as additional rubbers for the production of rubber vulcanizates. Preferred synthetic rubbers are, for example, described in W. Hofmann, Kautschuktechnologie, Gentner Verlag, Stuttgart 1980 and I. Franta, Elastomers and Rubber Compounding Materials, Elsevier, Amsterdam 1989. These include, among others:

BR - ordinary polybutadiene

ABR - butadiene / C 1 -C 4 -alkyl acrylic acid copolymers

CR - polychloroprene

IR - polyisoprene

SBR - styrene / butadiene copolymers with a styrene content of 1 to 60, preferably 20 to 50 wt.

IIR - isobutylene / isoprene copolymers

NBR - butadiene / acrylonitrile copolymers with acrylonitrile content from 5 to 60, preferably 10 to 40 wt.

HNBR - partially hydrogenated or fully hydrogenated NBR rubber

EPDM - ethylene / propylene / diene copolymers

EP2536769 B1

V9788PL00 / TS and mixtures of these rubbers. Natural rubber, emulsion SBR rubbers and SBR rubbers polymerized in solution with a glass transition temperature above -50 ° C, which can be modified with silyl ethers or other functional groups, such as described in EP-A-0 447 066, a polybutadiene rubber with a high content of 1,4-cis units (> 90%), which is produced on catalysts based on Ni, Co, Ti or Nd and polybutadiene rubber with a vinyl configuration content from 0 to 75% and mixtures thereof.

[0060] The rubber mixtures / rubber mixtures containing polybutadiene according to the invention are a further object of the invention and as a rule they contain 5 to 300 parts by weight of active or inactive filler, such as,

- highly dispersed silicas, produced for example by precipitation from silicate solutions or by flame hydrolysis of silicon halides, with specific surfaces from 5 to 1000, ₂ preferably 20 to 400 m²/ g (BET surface) and primary particle sizes from 10 to 400 nm. Silicas can also be present as mixed oxides with other metal oxides, such as Al, Mg, Ca, Ba, Zn, Zr, Ti oxides,

- synthetic silicates, such as aluminum silicate, alkali metal silicates, such as magnesium silicate or ₂ calcium silicate, with BET surfaces from 20 to 400 m²/ g and primary particle sizes from 10 to 400 nm,

- natural silicates such as kaolin and other naturally occurring silicas,

- glass fibers and glass fiber products (mats, strands), or glass microspheres,

- metal oxides, such as zinc oxide, calcium oxide, magnesium oxide, alumina,

- metal carbonates, e.g., magnesium carbonate, calcium carbonate, zinc carbonate,

- metal hydroxides, e.g. aluminum hydroxide, magnesium hydroxide,

- metal salts, e.g. zinc or magnesium [alpha], [beta] unsaturated fatty acids, e.g. acrylic acid or methacrylic acid, containing 3 to 8 carbon atoms, such as zinc acrylate, zinc diacrylate, zinc methacrylate , zinc dimethacrylate and mixtures thereof;

- I think. Soots intended for use here are produced by the flame and oven method₂ or gas and have BET surfaces from 20 to 200 m²/ g, such as, for example, SAF, ISAF, HAF, FEF or GPF carbon blacks.

- rubber gels, in particular gels based on polybutadiene, butadiene / styrene copolymers, butadiene / acrylonitrile and polychloroprene copolymers.

[0061] Zinc diacrylates, highly dispersed silicas and carbon black are particularly preferred.

EP2536769 B1

V9788PL00 / TS [0062] Said fillers can be used alone or in a mixture. In a particularly preferred embodiment, the rubber mixtures contain as a filler a mixture of light fillers, such as highly dispersed silicas and soot, the mixing ratio of light fillers to soot being preferably in the range of 0.05 to 20, preferably 0.1 to 10.

[0063] The fillers are preferably added to the polybutadiene solution according to the invention as solids or as a suspension in water or in a solvent. The rubber solution can be prepared earlier, but preferably a solution derived directly from polymerization is used. Then the solvent is removed thermally or preferably with the help of steam. The conditions for this stripping process can be easily determined by means of preliminary experiments.

[0064] Furthermore, it is preferred that the fillers are added to the solid polybutadiene of the invention or mixed rubbers and mixed in a known manner, e.g., using a kneader.

[0065] The rubber mixtures / rubber mixtures according to the invention optionally further comprise a crosslinker. Sulfur or peroxides can be used as crosslinking agent, with sulfur being particularly preferred. The rubber mixtures according to the invention may contain further rubber auxiliaries, such as reaction accelerators, anti-aging agents, heat stabilizers, anti-light agents, ozone-protecting agents, processing aids, plasticizers, sticking agents, blowing agents, dyes, pigments, waxes, inactive fillers, organic acids, vulcanization retarders, metal oxides and activators, like triethanolamine, polyethylene glycol, hexanetriol etc. which are known in the rubber industry.

[0066] In preferred rubber mixtures with highly active precipitated silicic acid, it is preferred to use additional filler activators. Preferred filler activators are sulfur-containing silyl ethers, in particular bis- (trialkoxysilyl-alkyl) -polysulfides, as described in DE-A2.141.159 and DE-A-2.255.577, oligomers and / or polymers of sulfur-containing silyl ethers DE-A4.435.311 and EP-A-0 670 347, mercaptoalkyltrialkoxysilanes, in particular mercaptopropyltriethoxysilane and thiocyanatoalkylsilyl ether as described in DE-A-195 44 469.

[0067] Rubber auxiliaries are used in usual amounts which are adapted, inter alia, to the purpose of use. Common amounts are, for example, from 0.1 to 50% by weight, based on the rubber.

[0068] Further mixing of the rubber with the other mentioned rubber auxiliaries, crosslinking agents and accelerators can be carried out in the usual manner with the help of suitable mixing aggregates, such as rollers, internal mixers and mixing extruders.

[0069] Preparation of mixtures and vulcanization is described, for example, in more detail in Encyclopedia of Polymer Science and Engineering, vol. 4, page. 66 and following (preparation of the mixture) and volume 17, page. 666 and following (vulcanization).

[0070] The vulcanization of the rubber mixtures according to the invention can take place at ordinary temperatures from 100 to 200 ° C, preferably 130 to 180 ° C (optionally at a pressure of 10 to 200 bar).

[0071] The rubber compounds according to the invention are perfectly suitable for the production of molded parts of all types.

[0072] Non-limiting examples of such fittings are O-rings, profiles, seals, membranes, tires, tire treads, vibration damping elements and hoses.

[0073] Various tire components and tire treads are particularly preferred.

EP2536769 B1

V9788EN00 / TS [0074] Furthermore, the rubber mixtures according to the invention are suitable for modifying the impact strength of thermoplastics, in particular polystyrene and styrene / acrylonitrile polymers.

[0075] For the production of modified impact molding masses, such as PS-HI or ABS, the polymer according to the invention (synonymous with polybutadiene) is preferably first dissolved in the presence of vinylaromatic monomers, in particular in the presence of styrene, alpha-methylstyrene, alpha-methylstyrene dimer, p-methylstyrene, divinylbenzene and / or other ring substituted alkylstyrenes, preferably containing 2 to 6 C atoms in the alkyl residue. At this point, there is a solution of the polymer in the vinylaromatic substance.

[0076] Then, by radical polymerization of a vinylaromatic polymer solution or in the presence of an ethylenically unsaturated nitrile monomer and optionally with the addition of a further vinylaromatic monomer and optionally in the presence of solvents by a known polymerization method in bulk, in solution or in suspension, in a continuous, semi-continuous or batchwise manner a molding polymer solution is produced.

[0077] Advantageously, up to 30 wt.%, Particularly preferably up to 20 wt.%, Can be added. acrylic monomer or maleic acid derivative, relative to the total amount of monomers.

[0078] When radical polymerization is carried out in solution, aromatic hydrocarbons, such as toluene, ethylbenzene, xylenes and ketones, such as acetone, methyl ethyl ketone, methyl propyl ketone, methyl butyl ketone and mixtures of these solvents are considered as solvents. Ethylbenzene, methyl ethyl ketone and acetone and mixtures thereof are preferred.

[0079] The polymerization is preferably started with a radical primer, however it can also be carried out thermally; the molecular weight of the resulting polymer can be adjusted by means of a molecular weight regulator.

[0080] Suitable radical radical polymerization initiators are radical peroxides that are graft active.

[0081] Normal molecular weight regulators, such as mercaptans / thiols, olefins, e.g., tert.-dodecylthiol, n-dodecylthiol, cyclohexene, terpinols, alpha-methylstyrene dimer can be used to adjust molecular weights.

[0082] The method can be implemented as batch, semi-continuous and continuous.

[0083] The molding masses of the invention can be thermoplastically processed into moldings by extrusion, injection, calendering, blowing hollow bodies, pressing and sintering. [0084] The use of rubber mixtures for golf balls, in particular golf ball cores, is particularly suitable.

[0085] Next, the invention will be explained in more detail based on examples.

Examples

Example 1

Catalyst preparation and preforming:

[0086] 7.5 ml (42 mmol) of diisobutylhydroaluminum, 1.2 ml (12 mmol) of isoprene and 11.3 ml (3 mmol) of a 0.265 molar solution of a Neodymium compound with Versatic acids were placed in a dry Schlenk vessel, neutralized with argon. ™ in hexane. Stir 90 minutes at 50 ° C. Then cooled to 5 ° C and

EP2536769 B1

V9788PL00 / TS 8 ml (2 mmol) of 0.25 molar solution of ethyl aluminum sesquichloride in hexane was added. The pre-formed catalyst solution was allowed to stand overnight at room temperature and then used for polymerization.

Polymerization:

[0087] A dry glass autoclave with a capacity of 1.9 L, neutralized with argon, was filled with 580 g of hexane (dried over a molar sieve), 1.68 mL of the preformed catalyst solution described above and 120 g of butadiene. Heat to 65 ° C and polymerize with stirring for 90 minutes. Samples were taken to determine the degree of conversion. The degree of conversion of butadiene after polymerization was 95%.

[0088] To obtain a pot life, the polymer solution was heated by heating the walls for 60 minutes to 105 ° C.

[0089] Then 586 g of a highly viscous solution was dropped and 2 ml of methanol and 0.6 g of bis [3-tert.-butyl-2-hydroxy-5-methylphenyl] methane were introduced. The polymer was then dried at 70 ° C under vacuum. Weight after drying: 99.3 g Mooney viscosity (ML 1 + 4 at 100 ° C): 43 MU; ML relaxation after 30 seconds: 5.4%;

solution viscosity (5.43% in toluene at room temperature): 183 mPas, solution viscosity to Mooney viscosity ratio (LV / ML): 4.3.

RGM ratio and macromolecule inertia radius (RMS):

[0090] For determining the RGM ratio, the polybutadiene of the invention was eluted with AF4 and analyzed. For sample processing and analysis data, refer to pages 4 and 5 of the description.

[0091] First, the radius of inertia (RMS) of the polybutadiene according to the invention was determined. We refer to pages 3, 4 and 5 of the description here.

[0092] Fig. 2 shows the ray distribution of polybutadiene according to the invention plotted as a differential ray distribution (solid line) and as an integral ray distribution (dashed line). The total proportion of rays with a radius of inertia greater than 100 nm is 1.4%. The half width of the ray distribution is 29.0 nm.

[0093] To calculate the increase in the RGM ratio, a statistical average was created from 5 numbers each, using the numbers of the two closest measurement values ​​below and above the molar mass given, and the molar mass itself.

[0094] The radius of inertia is usually abbreviated as RMS. The increase in the RGM ratio is calculated in the representation of the double logarithmic scale as the increase in the radius of inertia along with the molar mass. For this purpose, the natural logarithm of molar mass and RMS inertia radius was calculated. The increase in the RGM ratio above the special molar mass range is shown by the quotient of the RMS natural logarithm difference at the boundaries of the area under consideration by the difference of natural molar mass logarithms at the boundaries of the area concerned.

[0095] Table 1 shows the numerical values ​​determined:

EP2536769 B1

V9788PL00 / TS

Table 1

<td></td><td>Mass molar</td><td>ln mass molar</td><td>RMS</td><td>ln RMS</td><td>RGM ratio increase (quotient of RMS ln difference by molar mass difference)</td><td></td>

<td>Linear polymeric main faction</td><td> 250.000</td><td> 12,43</td><td> 33,6</td><td> 3,51</td><td></td><td></td>

<td></td><td> 1.000.000</td><td> 13,82</td><td> 69,4</td><td> 4,24</td><td></td><td></td>

<td>Difference</td><td></td><td> 1,39</td><td></td><td> 0,73</td><td> 0,52</td><td>Height No. 1 for RGM</td>

<td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>Polymer fraction with branches with long chains</td><td> 1.000.000</td><td> 13,82</td><td> 69,4</td><td> 4,24</td><td></td><td></td>

<td></td><td> 10.000.000</td><td> 16,12</td><td> 109,8</td><td> 4,70</td><td></td><td></td>

<td>Difference</td><td></td><td> 2,30</td><td></td><td> 0,46</td><td> 0,20</td><td>Height No. 2 for RGM</td>

[0096] Fig. 3 shows a graphical representation of the RGM ratio of polybutadiene according to the invention. A smaller increase of more than 1 million g / mol of molar mass can be clearly seen. This means that the polybutadiene according to the invention below 1 million g / mol of molar mass has a linear structure, whereas the molar mass above it has long chain branches.

Comparative example

Polymerization without catalyst formation and without a lifetime [0097] A dry glass autoclave with a capacity of 1.9 l, neutralized with argon, was filled with 8500 g of hexane (dried over molecular sieve), 23.0 ml of a 18.45% solution of diisobutylhydroaluminum in hexane, 2.75 ml of a 40% solution of neodymium compound with Versatic ™ acid in hexane, 5.1 ml of a 10% solution of ethyl aluminum sesquichloride in hexane and 1300 g of butadiene. The whole was heated to 73 ° C and polymerized for 90 minutes while stirring. Then 1012 g of a highly viscous solution was dropped and mixed with 2 ml of methanol and 2.5 g of bis- [3-tert.-butyl-2-hydroxy-5-methylphenyl] methane.

The polymer was then dried at 70 ° C under vacuum. Weight after drying: 1 29.5 g; Mooney viscosity (ML 1 + 4 at 100 ° C): 43 MU; ML relaxation after 30 seconds: 6.2%; solution viscosity (5.43% in toluene at room temperature): 663 mPas, solution viscosity to Mooney viscosity ratio (LV / ML): 15.4.

EP2536769 B1

V9788PL00 / TS

RGM ratio and inertia ray distribution:

[0098] Analogously to example 1, the ratio RGM and the inertia radius of polybutadiene macromolecules were also determined for the comparative example.

[0099] Fig. 4 shows the distribution of rays for the comparative example, plotted as a differential distribution (solid line) and as an integral distribution (dashed line). The total proportion of rays with a radius of inertia greater than 100 nm is 12.2%. The half width of the ray distribution is 50.7 nm.

[0100] To calculate the increase in the RGM ratio, a statistical average was created from 5 numbers each, using the numbers of the two closest measurement quantities below and above the molar mass given, and the molar mass itself.

[0101] The radius of inertia is usually abbreviated as RMS. The increase in the RGM ratio is calculated in the representation of the double logarithmic scale as the increase in the radius of inertia along with the molar mass. For this purpose, the natural logarithm of molar mass and RMS inertia radius was calculated. The increase in the RGM ratio above the special molar mass range is shown by the quotient of the RMS natural logarithm difference at the boundaries of the area under consideration by the difference of natural molar mass logarithms at the boundaries of the area concerned.

[0102] Tab. 2 shows the numerical values ​​determined:

Tab. 2

<td></td><td>Mass molar</td><td>ln molar mass</td><td>RMS</td><td>ln RMS</td><td>RGM ratio increase (quotient of lnRMS difference by ln molar difference)</td><td></td>

<td>Linear polymeric main faction</td><td> 250000</td><td> 12,43</td><td> 34,2</td><td> 3,53</td><td></td><td></td>

<td></td><td> 1000000</td><td> 13,82</td><td> 68,9</td><td> 4,23</td><td></td><td></td>

<td>Difference</td><td></td><td> 1,39</td><td></td><td> 0,70</td><td> 0,51</td><td>Height No. 1 for RGM</td>

<td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>Polymer fraction with branches with long chains</td><td> 1000000</td><td> 13,82</td><td> 68,9</td><td> 4,23</td><td></td><td></td>

<td></td><td> 10000000</td><td> 16,12</td><td> 193,5</td><td> 5,27</td><td></td><td></td>

<td>Difference</td><td></td><td> 2,30</td><td></td><td> 1,03</td><td> 0,45</td><td>Height No. 2 for RGM</td>

[0103] Fig. 5 shows a graphical representation of the RGM ratio for comparative polybutadiene. It can be clearly seen that an increase from 1 million g / mol of molar mass is approximately identical to an increase to 1 million g / mol of molar mass. This means that the comparative polybutadiene has a completely linear structure.

EP2536769 B1

V9788PL00 / TS