WO2000004066A1

WO2000004066A1 - Method for polymerizing conjugated diolefins (dienes) with rare earth catalysts in the presence of vinylaromatic solvents

Info

Publication number: WO2000004066A1
Application number: PCT/EP1999/004741
Authority: WO
Inventors: Heike Windisch; Werner Obrecht; Gisbert Michels; Norbert Steinhauser; Thomas Schnieder
Original assignee: Bayer Aktiengesellschaft
Priority date: 1998-07-18
Filing date: 1999-07-07
Publication date: 2000-01-27
Also published as: KR20010071951A; CA2337423A1; JP2002520457A; RU2001104876A; EP1117713A1; DE19832446A1; HK1039952A1; AU5032599A; TW546312B; CN1309674A

Abstract

Conjugated diolefins, optionally combined with other unsaturated compounds that may be copolymerized with diolefins are polymerized by conducting polymerization of the diolefins in the presence of catalysts based on compounds of rare earth, cyclopentadiene and organoaluminum compounds in the presence of aromatic vinyl compounds as solvents at temperatures ranging from -30 °C to +100 °C. The invention provides a simple method for producing copolymer solutions such as styrol-butadiene-copolymers having different styrol content and different contents of 1,2- and cis-units in aromatic vinyl compounds in relation to the diolefin, which can be further processed to obtain ABS or HIPS.

Description

Process for the polymerisation of conjugated diolefins (dienes) with rare earth catalysts in the presence of vinyl aromatic solvents

The present invention relates to a process for the polymerization of conjugated diolefins in the presence of rare earth catalysts and in the presence of aromatic vinyl compounds.

The polymerization of conjugated diolefins in the presence of a solvent has been known for a long time and is described, for example, by W. Hoffmann, Rubber Technology Handbook, Hanser Publishers (Carl Hanser Verlag) in Munich, Vienna, New York, 1989. For example, polybutadiene is now predominant

Dimensions produced by solution polymerization with the aid of coordination catalysts of the Ziegler-Natta type, for example based on titanium, cobalt, nickel and neodymium compounds, or in the presence of alkyl lithium compounds. The solvent used depends heavily on the type of catalyst used. Benzene or toluene and aliphatic or cycloaliphatic are preferred

Hydrocarbons used.

A disadvantage of the polymerization processes carried out today for the production of poly-diolefins, such as BR, IR or SBR is the time-consuming work-up of the polymer solution to isolate the polymers, for example by stripping with

Water vapor or direct evaporation. A further disadvantage, particularly if the polymerized diolefins are to be further processed as impact modifiers for plastic applications, is that the polymeric diolefins obtained first have to be dissolved again in a new solvent, for example styrene, in order then to e.g. to be processed into acrylonitrile-butadiene-styrene copolymer (ABS) or high-impact polystyrene (HIPS).

US 3299178 describes a catalyst system based on TiCL / iodine / Al (iso-Bu) ₃ for the polymerization of butadiene in styrene to form homogeneous polymer. butadiene claimed. With the same catalyst system, Harwart et al. in Plaste and Kautschuk, 24/8 (1977) 540 describes the copolymerization of butadiene and styrene and the suitability of the catalyst for the production of polystyrene.

US 5096970 and EP 304088 describe a process for the preparation of polybutadiene in styrene using catalysts based on neodymphosphonates, organic aluminum compounds such as di (isobutyl) aluminum hydride (DIBAH) and based on a halogen-containing Lewis acid such as Ethylaluminum sesquichloride, described, in which butadiene is converted into styrene without further addition of inert solvents to a 1,4-cis-polybutadiene. A disadvantage of this catalyst is that the polymers obtained have a very low 1,2-unit content of less than 1%. It is disadvantageous because a higher 1,2-content of polymers has a positive effect on the bond between rubber and the polymer matrix, e.g. Homo- or copolymers of vinyl aromatic compounds.

From US 43 11 819 it is known to use anionic initiators for the polymerization of butadiene in styrene. According to the patent examples, an SBR rubber suitable for HIPS use could be obtained by polymerizing either at an initial butadiene in styrene concentration of about

35 wt .-%, the polymerization was stopped at a monomer conversion of butadiene of about 25%, or by increasing the monomer conversion of butadiene to about 36% by a high butadiene concentration of about 55% by weight, so that the majority of the used In both cases, butadiene must be separated off by distillation before the styrenic rubber solution is used for impact modification.

The disadvantage of anionic initiators is that butadiene-styrene

Copolymers (SBR) are formed which, based on the butadiene units, allow only a slight control of the microstructure. It is not possible with anionic

Initiators to produce a high cis-containing SBR, in which the 1, 4-cis content over Is 40%. By adding modifiers, only the proportion of 1,2- or 1,4-trans units can be increased, the 1,2-content in particular leading to an increase in the glass transition temperature of the polymer. This fact is disadvantageous above all because SBR is formed in this process, which results in a further increase in the glass transition temperature with increasing styrene content compared to homopolymeric polybutadiene (BR). When the rubber is used for impact modification of, for example, HIPS or ABS, however, a high glass transition temperature of the rubber has a disadvantageous effect on the low-temperature toughness of the material, so that rubbers with low glass transition temperatures are preferred.

Kobayashi et al. was described, for example, in J. Polym. Be., Part A, Polym. Chem., 33 (1995) 2175 and 36 (1998) 241 describes a catalyst system consisting of halogenated rare earth acetates, such as Nd (OCOCCl ₃ ) ₃ or Gd (OCOCF ₃ ) ₃ , with tri (isobutyl) aluminum and diethyl aluminum chloride , which enables the copolymerization of butadiene and styrene in the inert solvent hexane. A disadvantage of these catalysts, in addition to the presence of inert solvents, is that the catalyst activity drops from less than 5 mol% to less than 10 g of polymer / mmol of catalyst h, even with a small amount of styrene, and that the 1,4-cis content of the polymer increases with increasing Styrene content decreases significantly.

The advantage of SBR over pure BR for use in plastic modification, e.g. as impact modifiers for ABS and HIPS, consists in the fact that the refractive indices of rubber and matrix approach each other with increasing styrene content, which leads to an improvement in the transparency of the modified plastics. On the other hand, with increasing styrene content, the glass temperature of the

Rubber, which then has a negative impact on the impact strength of the plastic.

The rubber solutions in styrene described in the listed patent publications were used for the production of HIPS in that the rubber solutions in styrene were added with free radical initiators after removal of the unreacted diolefin.

On the other hand, for the production of ABS, the rubber is used in a matrix of acrylonitrile-styrene copolymers (SAN). In contrast to the production of

HIPS in ABS, the SAN matrix is incompatible with polystyrene. If, in addition to the rubber, homopolymers of the solvent, such as polystyrene, are formed in the polymerization of the diolefins in vinylaromatic solvents, the incompatibility of the SAN matrix with the polymerized vinylaromatics leads to a significant deterioration in the material properties of the ABS in the production of ABS.

It was an object of the present invention to provide a process for the polymerization of conjugated diolefins in vinylaromatic solvents, with which copolymers are obtained in which the polymer composition with regard to the content of vinylaromatics and diolefins and with regard to the selectivity of the polymerized diolefins, i.e. e.g. Content of cis double bonds and of 1,2 units with pendant vinyl groups can be varied, the glass transition temperature of the polymer below -60 ° C, preferably below -70 ° C.

The present invention therefore relates to a process for copolymerizing conjugated dienes with vinylaromatic compounds, which is characterized in that the polymerization of the conjugated dienes in the presence of catalysts consists of

a) at least one compound of the rare earth metals,

b) at least one cyclopentadiene and

c) at least one organoaluminum compound or consisting of

a) at least one compound of rare earth metals and

c) at least one organoaluminum compound

and in the presence of vinyl aromatic compounds at temperatures from -30 to + 100 ° C, the molar ratio of components (a) :( b) :( c) in the range from 1: 0.01 to 1.99: 0, 1 to 1000 or where the molar ratio of

Component (a) :( c) is in the range from 1: 0.1 to 1000, component (a) of the catalyst in amounts of 1 μmol to 10 nmol, based on 100 g of the conjugated diolefins used, and the aromatic vinyl compound in Quantities from 50 g to 2000 g, based on 100 g of the conjugated diolefins used, are used.

As conjugated diolefins (dienes), e.g. 1,3-butadiene, 1,3-isoprene, 2,3-dimethylbutadiene, 2,4-hexadiene, 1,3-pentadiene and / or 2-methyl-1,3-pentadiene can be used.

It is of course also possible according to the process of the invention to use other unsaturated compounds, such as ethylene, propene, 1-butene, 1-pentene, 1-hexene and / or 1-octene, preferably ethylene and / or propene, in addition to the conjugated diolefins which can be copolymerized with the diolefins mentioned.

The amount of unsaturated compounds which can be copolymerized with the conjugated diolefins depends on the intended use of the desired copolymers and can easily be determined by appropriate preliminary tests. It is usually 0.1 to 80 mol%, before adds 0.1 to 50 mol%, particularly preferably 0.1 to 30 mol%, based on the diolefin.

The molar ratio of components (a) :( b) :( c) in the catalyst used is in the range from 1: 0.1 to 1.9: 3 to 500, particularly preferably 1: 0.2 to

1.8: 5 to 100. The molar ratio of component (a) :( c) is preferably in the range from 1: 3 to 500, in particular 1: 5 to 100.

Suitable compounds of the rare earth metals (component (a)) are, in particular, those which are selected from

an alcoholate of rare earth metals,

a phosphonate, phosphinate and / or phosphate of rare earth metals,

a carboxylate of rare earth metals,

a complex compound of rare earth metals with diketones and / or

- An addition compound of the halides of rare earth metals with one

Oxygen or nitrogen donor compound.

The aforementioned compounds of rare earth metals are described in more detail, for example, in EP 11 184.

The compounds of the rare earth metals are based in particular on the elements with atomic numbers 21, 39 and 57 to 71. Lanthanum, praseodymium or neodymium or a mixture of elements of the rare earth metals, which contains at least one of the elements lanthanum, praseodymium or, are preferably used as rare earth metals Contains neodymium to at least 10 wt .-%. Lanthanum or neodymium, which in turn, are very particularly preferably used as rare earth metals can be mixed with other rare earth metals. The proportion of lanthanum and / or neodymium in such a mixture is particularly preferably at least 30% by weight.

Suitable alcoholates, phosphonates, phosphinates and carboxylates of the rare earth metals or as complex compounds of the rare earth metals with diketones are, in particular, those in which the organic group contained in the compounds in particular straight-chain or branched alkyl radicals having 1 to 20 carbon atoms, preferably 1 to 15 carbon atoms , contains, such as methyl, ethyl, n-propyl, n-butyl, n-pentyl, isopropyl, isobutyl, tert-butyl, 2-ethylhexyl, neo-pentyl, neo-octyl, neo-decyl or neo-dodecyl.

Rare earth alcoholates e.g. called:

Neodymium (III) -n-propanolate, neodymium (III) -n-butanolate, neodymium (III) -n-decanolate, neodymium (III) -isopropanolate, neodymium (III) -2-ethylhexanolate, praseodymium (III) -n-propanolate, praseodymium (III) -n-butanolate, praseodymium (III) -n-decanolate, praseodymium (III) -isopropanolate, praseodymium (III) -2-ethylhexanolate, lanthanum ( III) -n-propanolate, lanthanum (III) -n-butanolate, lanthanum (III) -n-decanolate, lanthanum (III) -isopropanolate and lanthanum (III) -2-ethylhexanolate, preferably neodymium ( III) -n-butanolate, neodymium (III) -n-decanolate and neodymium (III) -2-ethyl-hexanolate.

As the phosphonates, phosphinates and rare earth phosphates, e.g. called: neodymium (III) -dibutylphosphonate, neodymium (III) -dipentylphosphonate, neodymium (III) -dihexylphosphonate, neodymium (III) -diheptylphosphonate, neodymium (III) -dioctyl-phosphonate, neodymium (III) -dinonylphymonate, III) didodecylphosphonate,

Neodymium (III) -dibutylphosphinate, Neodymium (III) -dipentylphosphinate, Neodymium (III) -dihexylphosphinate, Neodymium (III) -dihepytylphosphinate, Neodymium (III) -dioctylphosphinate, Neodymium (III) -dinonidymatephosphinate, Neodymium (III) and neodymium (IΙI) phosphate, preferably neodymium (III) dioctyl phosphonate and neodymium (III) dioctyl phosphinate. Suitable carboxylates of rare earth metals are:

Lanthanum (III) propionate, lanthanum (III) diethyl acetate, lanthanum (III) -2-ethylhexanoate, lanthanum (III) stearate, lanthanum (III) benzoate, lanthanum (III) cyclohexane carboxylate, lanthanum (III) - oleate, lanthanum (III) versatate, lanthanum (III) naphthenate, praseodymium (III) propionate, praseodymium (III) diethyl acetate, praseodymium (III) -2-ethylhexanoate, praseodymium (III) stearate, praseodymium ( III) benzoate, praseodymium (III) cyclohexane carboxylate, praseodymium (III) oleate, praseodymium (III) versatate, praseodymium (III) naphthenate, neodymium (IΙI) propionate, neodymium (III) diethyl acetate, neodymium ( III) -2-ethylhexanoate, neodymium (III) stearate, neodymium (III) benzoate, neodymium (III) cyclohexane carboxylate, neodymium (III) oleate, neodymium (III) versatate and neodymium (III) naphthenate, preferably neodymium (III) -2-ethylhexanoate, neodymium (III) versatate and neodymium (III) naphthenate. Neodymium versatate is particularly preferred.

The following are mentioned as complex compounds of the rare earth metals with diketones: lanthanum (III) acetylacetonate, praseodymium (III) acetylacetonate and neodymium (III) acetyl acetonate, preferably neodymium (III) acetylacetonate.

Examples of addition compounds of the halides of rare earth metals with an oxygen or nitrogen donor compound are: lanthanum (III) chloride with tributyl phosphate, lanthanum (III) chloride with tetrahydrofuran,

Lanthanum (III) chloride with isopropanol, lanthanum (III) chloride with pyridine, lanthanum (III) chloride with 2-ethylhexanol, lanthanum (III) chloride with ethanol, praseodymium (III) chloride with tributyl phosphate, praseodymium (III) chloride with tetrahydrofuran, praseodymium (III) chloride with isopropanol, praseodymium (III) chloride with pyridine, praseodymium (III) chloride with 2-ethylhexanol, praseodymium (III) chloride with ethanol, neodymium ( III) chloride with

Tributyl phosphate, neodymium (III) chloride with tetrahydrofuran, neodymium (III) chloride with isopropanol, neodymium (III) chloride with pyridine, neodymium (III) chloride with 2-ethylhexanol, neodymium (III) chloride with ethanol, lanthanum (III) bromide with tributyl phosphate, lanthanum (III) bromide with tetrahydrofuran, lanthanum (III) bromide with isopropanol, lanthanum (III) bromide with pyridine, lanthanum (III) bromide with 2- Ethylhexanol,

Lanthanum (III) bromide with ethanol, praseodymium (III) bromide with tributyl phosphate, Praseodymium (III) bromide with tetrahydrofuran, praseodymium (III) bromide with isopropanol, praseodymium (III) bromide with pyridine, praseodymium (III) bromide with 2-ethylhexanol, praseodymium (III) bromide with ethanol, neodymium (III) bromide with tributyl phosphate, neodymium (III) bromide with tetrahydrofuran, neodymium (III) bromide with iso-propanol, neodymium (III) bromide with pyridine, neodymium (III) bromide with 2-ethylhexanol and neodymium ( III) bromide with ethanol, preferably lanthanum (III) chloride with tributyl phosphate, lanthanum (III) chloride with pyridine, lanthanum (III) chloride with 2-ethylhexanol, praseodymium (III) chloride with tributyl phosphate, praseodymium (III) -chloride with 2-ethylhexanol, neodymium (III) chloride with tributyl phosphate, neodymium (III) chloride with tetrahydrofuran, neodymium (III) chloride with 2-ethylhexanol, neodymium (III) chloride with pyridine, neodymium (III ) chloride with 2-ethylhexanol and neodymium (III) chloride with ethanol.

Neodymium versatate, neodymium octanoate and / or neodymium naphthenate are very particularly preferably used as compounds of the rare earth metals.

The above-mentioned compounds of rare earth metals can be used both individually and in a mixture with one another. The most favorable mixing ratio can easily be determined by appropriate preliminary tests.

As cyclopentadienes (component (b)), compounds of the formulas (I), (II) or (III)

used in which R ¹ to R ^{9 are the} same or different or are optionally linked to one another or are condensed on the cyclopentadiene of the formula (I), (II) or (III), and for hydrogen, a C _r to C ₃₀ alkyl group, a C ₆ - to C, ₀ -aryl group, a C ₇ - to C ₄₀ -alkylaryl group and a C ₃ - to C ₃₀ -silyl group, where the alkyl groups can be either saturated or mono- or polyunsaturated and heteroatoms such as oxygen , Nitrogen or halides. In particular, the radicals can be hydrogen, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, phenyl, methylphenyl, cyclohexyl, benzyl, trimethylsilyl or trifluoromethyl.

Examples of the cyclopentadienes are the unsubstituted cyclopentadiene, methylcyclopentadiene, ethylcyclopentadiene, n-butylcyclopentadiene, tert-butylcyclopentadiene, vinylcyclopentadiene, benzylcyclopentadiene, phenylcyclopentadiene, trimethylsilylcyclopentadiene, 2-methadylophenadiene, 2-methadylophenadiene, 2-methadadylophenadiene, 2-methadadylophenadiene, 2-methadadylophenadiene, 2-methadadylophenadiene, 2-methadadylophenadiene Dimethylcyclopentadiene, trimethylcyclopentadiene, tetramethylcyclopentadiene,

Tetraphenylcyclopentadiene, tetrabenzylcyclopentadiene, pentamethylcyclopentadiene, pentabenzylcyclopentadiene, ethyl-tetramethylcyclopentadiene, trifluoromethyl-tetra-methylcyclopentadiene, indene, 2-methylindenyl, trimethylinden, hexamethylinden, heptamethyloren, phenyl or methyl-methylinden, 2-methylfluorene.

The cyclopentadienes can also be used individually or in a mixture with one another.

Suitable organoaluminum compounds (component (c)) are, in particular, alumoxanes and / or aluminum organyl compounds.

Aluminum-oxygen compounds which, as is known to the person skilled in the art, are obtained as alumoxanes and are obtained by contacting organoaluminum compounds with condensing components, such as water, and the non-cyclic or cyclic compounds of the formula (-Al (R) Represent 0-) _n , where R can be the same or different and for a linear or branched alkyl group is 1 to 10 carbon atoms, which may also contain heteroatoms, such as oxygen or nitrogen. In particular, R represents methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, tert-butyl, n-octyl or iso-octyl, particularly preferably methyl, ethyl or iso-butyl. Examples of alumoxanes are: methylalumoxane, ethylalumoxane and isobutylalumoxane, preferably methylalumoxane and isobutylalumoxane.

Compounds of the formula AlR _3.d X _d are used as aluminum organyl _compounds , where

R can be the same or different and for a Ci-Ci _Q aryl group and one

C ₇ - to C ₄₀ -alkylaryl group, where the alkyl groups can either be saturated or monounsaturated and can contain heteroatoms, such as oxygen or nitrogen,

X represents a hydrogen, an alcoholate, phenolate or amide and

d represents a number from 0 to 2.

As organoaluminum compounds of the formula

can in particular be used: trimethyl aluminum, triethyl aluminum, tri-n-propyl aluminum, tri-iso-propyl aluminum, tri-n-butyl aluminum, tri-iso-butyl aluminum, tripentyl aluminum, trihexyl aluminum, tricyclohexyl aluminum, trioctyl aluminum, di-, di-ethyl aluminum -butyl aluminum hydride, di-iso-butyl aluminum hydride, diethyl aluminum butanolate, diethyl aluminum methylidene (dimethyl) amine and diethyl aluminum imethylidene (methyl) ether, preferably trimethyl aluminum, triethyl aluminum, tri-iso-butyl aluminum and di-iso-butyl aluminum.

The organoaluminum compounds can in turn be used individually or as a mixture with one another. It is also possible to add a further component (d) to the catalyst components (a) to (c). This component (d) can be a conjugated diene, which is, for example, the same diene that is later to be polymerized with the catalyst. Butadiene and / or isoprene are preferably used.

If component (d) is added to the catalyst, the amount of (d) is preferably 1 to 1000 mol, based on 1 mol of component (a), particularly preferably 1 to 100 mol. 1 to 50 mol, based on 1 mol of component (a), of (d) are very particularly preferably used.

In the process according to the invention, the catalysts are used in amounts of preferably 10 μmol to 5 mmol of component (a), particularly preferably 20 μm to 1 mmol of component (a), based on 100 g of the monomers.

Of course, it is also possible to use the catalysts in any mixture with one another.

The process according to the invention is carried out in the presence of aromatic vinyl compounds, in particular in the presence of styrene, α-methylstyrene, α-methylstyrene dimer, p-methylstyrene, divinylbenzene and / or other alkylstyrenes with 2 to 6 carbon atoms.

Atoms in the alkyl radical, such as ethylbenzene, carried out.

The polymerization according to the invention is very particularly preferably carried out in the presence of styrene, α-methylstyrene, α-methylstyrene dimer and / or p-methylstyrene as solvent.

The solvents can be used individually or in a mixture; the most favorable mixture ratio can be easily determined by means of appropriate preliminary tests. The amount of aromatic vinyl compounds used is preferably 30 to 1000 g, very particularly preferably 50 to 500 g, based on 100 g of the monomers used.

The process according to the invention is preferred at temperatures from -20 to

90 ° C, particularly preferably carried out at temperatures of 20 to 80 ° C.

The process according to the invention can be carried out without pressure or at elevated pressure (0.1 to 12 bar).

The process according to the invention can be carried out continuously or batchwise, preferably in a continuous manner.

The solvent used in the process according to the invention need not be distilled off, but can remain in the reaction mixture. To this

It is possible, for example when styrene is used as solvent, to connect a second polymerization for the styrene, an elastomeric polydiene being obtained in a polystyrene matrix. In an analogous manner, acrylonitrile can be added to the styrenic polydiene solution before the second polymerization is carried out. In this way you get ABS. Such products are of particular interest as impact-modified thermoplastics.

It is of course also possible to remove part of the solvent and / or the unreacted monomers after the polymerization, preferably by distillation, if appropriate under reduced pressure, in order to achieve the desired

To get polymer concentration.

It is also possible to add further components to the polymer solution before or during the subsequent polymerization of the solvent, which can be initiated in a known manner, for example by free radicals or thermally, for example unsaturated organic compounds, such as acrylonitrile, methyl methacrylate, maleic anhydride or maleimides which copolymerize with the vinyl aromatic solvent. can be, and / or common aliphatic or aromatic solvents, such as benzene, toluene, dimethylbenzene, ethylbenzene, hexane, heptane or octane, and / or polar solvents, such as ketones, ethers or esters, which are usually used as solvents and / or diluents for the polymerization of the vinyl aromatic solvent can be used.

As already mentioned above, the process according to the invention is particularly economical and environmentally friendly, since the solvent used can be polymerized in a subsequent step, the polymer contained in the solvent being used to modify thermoplastics (e.g. to increase the impact strength).

The composition and thus the properties of the polymers obtained can be varied very widely by the process according to the invention.

It is e.g. possible to influence the microstructure of the resulting copolymers by varying the substituents of the cyclopentadiene used. For example the content of 1,2 units, i.e. of lateral double bonds in the polymer chain, and the content of 1,4-cis double bonds in the

Polymer chain. Furthermore, the type of substitution of the cyclopentadiene used has an influence on the copolymerization parameters, particularly with regard to the diolefins and vinyl aromatic solvents used. For example, the vinyl aromatic content in the resulting polymer can be affected by varying the catalyst composition.

It is also possible to influence the polymer composition by varying the reaction conditions, such as varying the ratio of diolefins and vinyl aromatic solvents used, the catalyst concentration, the reaction temperature and reaction time. Another advantage of the process according to the invention is that, in the direct polymerization in styrene, it is also possible to prepare and process further such low molecular weight polymers which are difficult to process and store as solids with a high cold flow or high stickiness.

The advantage of low molecular weight polymers is that even with a high content of the polymers, the solution viscosity remains as desired low and the solutions can thus be easily transported and processed.

According to the method of the invention, it is possible to polymerize

To obtain diolefins in vinylaromatic solvents copolymers of diolefins and vinylaromatics which, in contrast to the anionic initiators, have a high content of 1,4-cis double bonds, based on the diolefin content, and which continue to have a high catalyst activity and high conversion of diolefins used simple control of the microstructure, ie the content of lateral 1,2- and 1,4-cis units, the polymer composition and the molecular weight, enable.

Examples

The polymerizations were carried out in the absence of air and moisture under argon. The isolation of the polymers from the styrenic solution described in individual examples was carried out only for the purpose of characterizing the polymers obtained. The polymers can of course also be stored in the styrenic solution without insulation and processed further accordingly.

The styrene used as solvent for the diolefin polymerization was stirred under argon for 24 h over CaH ₂ at 25 ° C. and distilled off under reduced pressure at 25 ° C. (Examples 1 to 16). In order to show that the polymerization is also possible with stabilized styrene, in some examples the styrene was dried over molecular sieve 4A (Baylith) for 2 days and the polymerization was carried out in the presence of the stabilizer (bis (tert-butyl) benzate catechol, 15 ppm) (Examples 17 to 19).

The styrene content in the polymer is determined by means of NMR-NMR spectroscopy, the selectivity of the polybutadiene (1,4-cis, 1,4-trans and 1,2-content) is determined by means of IR spectroscopy, the determination the solution viscosity in a 5% by weight solution of the polymer in styrene using an Ubelohde viscometer at 25 ° C., the determination of the glass transition temperature T to _σ using DSC and the

Determination of the water content using Carl Fischer titration.

Examples 1 to 5

Catalyst aging

In a 100 ml Schlenk flask at 25 ° C to 20 ml of a 0.245 molar solution of neodymium (III) versatat (NDV) in hexane through a septum 7.2 g of butadiene, 0.57 ml of indene and 88.6 ml of one 10% solution of methylalumoxane in toluene (MAO), heated to 50 ° C with stirring for 2 hours and

Polymerization used. Polymerization

The polymerization was carried out in a 0.5-1 bottle, which was provided with a crown cap with an integrated septum. The specified amount of liquid butadiene was added to the styrene under argon and the specified amounts of a 1 molar solution of tri (isobutyl) aluminum in toluene (TIBA) as scavenger and the aged catalyst solution were then added using a syringe. During the polymerization, the temperature was adjusted by a water bath. The polymer was isolated after the specified reaction time by precipitating the polymer solution in methanol / BKF (BKF = bis [(3-hydroxy) (2,4-di-tert-butyl) (6-methyl) phenyl] methane) and one day in Vacuum drying cabinet dried at 60 ° C. The batch sizes, reaction conditions and the properties of the polymer obtained are given in Table 1.

Table 1: Examples 1 to 5

example

Catalyst solution i in ml 4.91 4.91 2.46 2.21 3.68

NDV in mmol 0.2 0.2 0.1 0.09 0.15

Polymerization

Styrene in ml 40 75 75 100 100

1,3-butadiene in g 10.7 21.0 19.5 15.6 25.6

TIBA (1 molar) in ml - - - 0.9 1.5

Temperature in ° C 40 50 40 50 50

Response time in h 3.2 1.5 3.5 3.5 3.5

polymer

Yield in g 6.7 20.7 12.8 20.2 38.8

Styrene content in mol% 5.3 18.9 10.4 29.8 37.9

Butadiene content in mol% 94.7 81.1 89.6 70.2 62.1 ice in% 63 55 58 53 51 Example ϊ 3 2 4 5 trans in% 32 41 35 38 41

1.2 in% 5 4 7 10 8 η (5% in styrene) in mPa-s 5.95 nb nb nb nb

Tg in ° C -97.5 nb -92 nb nb

Example 6

Catalyst aging

The catalyst aging was carried out analogously to Examples 1 to 5.

Polymerization

The polymerization was carried out in a 6-1 glass pot which was equipped with an anchor stirrer, a reflux condenser, connected to a cryostat with a temperature of -30 ° C., a double jacket, connected to a thermostat, an internal thermometer, a septum and an argon connection . Under argon, 292 g of liquid butadiene were added to 1050 ml of styrene at 25 ° C. and then 68.8 ml of the aged catalyst solution were added. The polymerization was carried out at 50 ° C. and stopped after 3 hours by adding 20 ml of acetone with 2 g of BKF.

The solids content of the polymer solution was 34%. The polymer has the following composition: 29.0 mol% styrene, 71.0 mol% butadiene (with 54% 1,4-cis, 41% 1,4-trans, 5% 1,2 units), the viscosity (5% by weight in styrene) is 15.3 mPa-s, the glass temperature is -86 ° C. Example 7-10

Catalyst aging

In a 100 ml Schlenk flask at 25 ° C to 20 ml of a 0.245 molar solution of neodymium (III) versatat (NDV) in hexane through a septum 7.1 g of butadiene, 0.80 ml of pentamethylcyclopentadiene and 147 ml of a 10% solution of methylalumoxane in toluene (MAO), heated to 50 ° C. for 2 hours with stirring and used for the polymerization.

Polymerization

The polymerization was carried out according to Examples 1 to 5, with various aluminum compounds being used as scavengers. The batch sizes, reaction conditions and the properties of the polymer obtained are given in Table 2.

Table 2: Examples 7 to 10

Example 1 8 9 ΪÖ ~~

Catalyst solution in ml 2.19 3.28 5.47 7.29

NDV in mmol 0.06 0.09 0.15 0.2

Polymerization

Styrene in ml 100 100 100 75

1,3-butadiene in g 10.2 15.4 25.8 21.8

TIBA (1 molar) in ml 0.6 0.9 1.5 -

TMA (1 molar) in ml - - - -

Temperature in ° C 50 50 50 50

Response time in h 3.5 3.5 3.5 2

polymer Example 7 8 9 10

Yield in g 9.1 19.3 42.2 24.5

Styrene content in mol% 22.6 29.0 44.8 20.4

Butadiene content in mol% 77.4 71.0 55.2 79.6 ice in% 65 58 53 47 trans in% 27 34 39 45

1.2 in% 8 8 8 9 η (5% in styrene) in mPa-s 12.6 15.2 15.6 nb

Tg in ° C -76.5 nb -78

Example 11-16

Catalyst aging

In a 100 ml Schlenk flask at 25 ° C to 20 ml of a 0.245 molar solution of neodymium (III) versatat (NDV) in hexane through a septum, 7.0 g of butadiene, 0.80 ml of pentamethylcyclopentadiene and 88 ml of a 10% solution of methylalumoxane in toluene (MAO), heated to 50 ° C. for 2 hours with stirring and used for the polymerization.

Polymerization

The polymerization was carried out in a 6-1 glass pot using an anchor stirrer

Reflux condenser, connected to a cryostat at a temperature of -30 ° C, a double jacket, connected to a thermostat, an internal thermometer, a septum and an argon connection. The polymerization was carried out analogously to Example 8. The batch sizes, polymerization conditions and results are summarized in Table 3. Table 3: Examples 11 to 16

Example 11 12 13 14 15 16

Catalyst solution: in ml 24.4 18.8 18.8 24.4 24.4 18.8

NDV in mmol 1 0.77 0.77 1 1 0.77

Polymerization

Styrene in ml 1300 2000 2000 3000 1300 2000

1,3-butadiene in g 207 317 305 405 200 301

MAO (1.66 molar) in ml 12 4.8 - - - -

TMA (1 molar) in: ml - - 7.7 10 - -

TIBA (1 molar) in ml - - - - 20 7.7

Temperature in ° C 47 50 50 50 50 50

Response time in h 3 5 5 5 3 3.8

polymer

Yield in g 278 377 392 461 289 358

Styrene content in mol% 39.8 24.2 24.9 23.4 37.9 53.6

Butadiene content in t mol% 60.2 75.8 75.1 76.6 62.1 46.4 ice in% 43 58 47 50 58 66 trans in% 48 33 44 41 34 23

1.2 in% 9 9 9 9 8 10 η (5% in styrene) in mPa-s 20 32 44 37 10 26

Tg in ° C -76.5 nb nb nb -77.0 nb

Example 17-19

Catalyst aging

In a 300 ml Schlenk flask at 25 ° C to 38.4 ml of a 0.3125 molar solution of neodymium (III) versatate (NDV) in hexane through a septum, 5.3 g of butadiene, 1.88 ml of pentamethylcyclopentadiene and 217 ml of a 10% strength solution of methylalumoxane in toluene (MAO) were added, the temperature was raised to 50 ° C. for 2 hours while stirring and used for the polymerization.

Polymerization

The polymerization was carried out in a 40-1 steel reactor with anchor stirrer (50 rpm). At room temperature, a solution of trimethylaluminum in hexane was added to a solution of butadiene in styrene as a scavenger, the reaction solution was heated to 50 ° C. within 45 minutes and the appropriate amount of catalyst solution was added. The reaction temperature was kept at 50 ° C. during the polymerization. After the reaction time had elapsed, the polymer solution was transferred to a second reactor (80 l reactor, anchor stirrer, 50 rpm) within 15 min and the polymerization was carried out by adding 3410 g of butanone

7.8 g Vulcanox KB and 25.5 g Irgafos TNPP stopped. To remove unreacted butadiene, the internal reactor pressure at 50 ° C. was reduced to 200 mbar within 1 h and to 100 mbar within 2 h.

The batch sizes, reaction conditions and the properties of the obtained

Polymers are given in Table 4. Table 4: Examples 17 to 19

Example 17 Ϊ8 Ϊ9

Catalyst solution in ml 166 161 161

NDV in mmol 7.5 7.3 7.3

Polymerization

Styrene in g 18070 16890 17154

Water content in ppm 83 30 37

1, 3-butadiene in g 3003 3700 3703

TMA (2 molar) in ml 17 5.6 7

Temperature in ° C 50 50 50

Response time in h 4.5 3.25 3

polymer

Solids content in% by weight 16.31 16.29 15.51

Styrene content in mol% 25.8 15.6 13.6

Butadiene content in mol% 74.2 84.4 86.4 ice in% 57 62 64 trans in% 35 29 26

1.2 in% 8 9 10 η (5% in styrene) in mPa-s 46 59 78

Tg in ° C -67 -74 -77

Mn in kg / mol 242 nb nb

Mw in kg / mol 332 nb nb

Examples 20 to 25 Catalyst aging

In a 100 ml Schlenk flask at 25 ° C to 20 ml of a 0.245 molar solution of neodymium (III) versatat (NDV) in hexane through a septum, 7.2 g of butadiene, 0.57 ml of indene and 88.6 ml of one 10% solution of methylalumoxane in toluene (MAO), heated to 50 ° C for 2 hours with stirring and used for the polymerization.

Polymerization

The polymerization was carried out in a 0.5-1 bottle, which was provided with a crown cap with an integrated septum. Under argon, the specified amount of liquid butadiene was added to the initially introduced styrene and a further component (α-methylstyrene, divinylbenzene or isoprene) via a cannula and the specified amounts of the aged catalyst solution were then added using a syringe.

During the polymerization, the temperature was adjusted by a water bath. After the specified reaction time, the polymer was isolated by precipitating the polymer solution in methanol / BKF and dried for one day in a vacuum drying cabinet at 60 ° C. The batch sizes, reaction conditions and the properties of the polymer obtained are given in Table 5.

Table 5: Examples 20 to 25

Example 20 21 22 23 24 25

Catalyst solution in ml 1.23 1.23 1.23 1.23 1.23 1.23

NDV in mmol 0.05 0.05 0.05 0.05 0.05 0.05

Polymerization

Styrene in ml 100 100 100 100 100 100

1,3-butadiene in g 21.1 22.8 22.3 23.6 25.1 21.5 α-methylstyrene 5 20 Example 20 21 22 23 24 25

Divinylbenzene 5 20

Isoprene in ml 5 20

Temperature in ° C 50 50 50 50 50 50

Response time in h 2.5 2.5 2.5 2.5 0.5 0.5

polymer

Yield in g 15.2 10.5 9.1 9.6 12.3 23.6

Styrene content in mol% nb 11 nb 10 nb 16

Butadiene content in mol% nb 89 nb 90 nb 84 ice in% nb 79 nb 77 nb nb trans in% nb 15 nb 18 nb nb

1.2 in% nb 6 nb 5 nb nb

Claims

claims

1. A process for the copolymerization of conjugated diolefins with vinyl aromatic compounds, characterized in that the polymerization of the conjugated diolefins in the presence of catalysts consisting of

a) at least one compound of the rare earth metals,

b) at least one cyclopentadienyl compound and

c) at least one organoaluminum compound

or consisting of

a) at least one compound of rare earth metals and

c) at least one organoaluminum compound

and in the presence of vinyl aromatic compounds at temperatures from -30 to + 100 ° C, the molar ratio of

Components (a) :( b) :( c) in the range from 1: 0.01 to 1.99: 0.1 to 1000 or where the molar ratio of components (a) :( c) in the range from 1: 0 , 1 to 1000, component (a) of the catalyst in amounts of 1 μmol to 10 mmol, based on 100 g of the conjugated diolefins used, and the aromatic vinyl compound in amounts of 50 g to 2000 g, based on 100 g of the used conjugated diolefins.

2. The method according to claim 1, characterized in that 1,3-butadiene, 1,3-isoprene, 2,3-dimethylbutadiene, 2,4-hexadiene, 1, 3-pentadiene and / or 2-methyl as conjugated diolefins - uses 1, 3-pentadiene. Process according to Claims 1 and 2, characterized in that the compounds of the rare earth metals are their alcoholates, phosphonates, phosphinates, phosphates and carboxylates and the complex compounds of the rare earth metals with diketones and / or the addition compounds of the halides of the rare earth metals with an oxygen or nitrogen - Donor connection can be used.

Process according to Claims 1 to 3, characterized in that neodymium versatate, neodymium octanate and / or neodymium naphthenate are used as compounds of the rare earth metals.

Process according to Claims 1 to 4, characterized in that compounds of the formulas (I), (II) and / or (III) are used as cyclopentadienes

(I) (II) (III)

used in which R ¹ to R ^{9 are the} same or different or are optionally connected to one another or are condensed on the cyclopentadiene of the formula (I), (II) or (III), and for hydrogen, a C 1 -C ₃₀ -alkyl group , a C ₆ - to C ₁₀ -aryl group, a C ₇ - to C ₄₀ -alkylaryl group, a C ₃ - to C ₃₀ -silyl group, where the alkyl groups can be either saturated or mono- or polyunsaturated and can contain heteroatoms.

6. Process according to Claims 1 to 5, characterized in that alumoxanes and / or aluminum organanyl compounds are used as organoaluminum compounds.

7. Process according to Claims 1 to 6, characterized in that a conjugated diolefin is used as additional component (d) in an amount of 1 to 1000 mol, based on 1 mol of component (a).

8. Process according to Claims 1 to 7, characterized in that styrene, α-methylstyrene, α-methylstyrene are used as aromatic vinyl compounds

Dimer, p-methylstyrene, divinylbenzene and / or alkylstyrenes with 2 to 6 carbon atoms in the alkyl radical are used.

9. Process according to Claims 1 to 8, characterized in that, in addition to the conjugated dienes, other unsaturated compounds are used which can be copolymerized with the diolefins mentioned, in amounts of 0.1 to 80 mol%, based on the conjugated diene used.