DE1292847B - Process for the production of 1,3-diene copolymers - Google Patents

Description

Some processes are known by which 1,3-dienes, such as butadiene, can be copolymerized with vinyl aromatic hydrocarbons such as styrene. In this process, mainly alkali metals, organic alkali compounds or radical-forming catalysts are used, and in general only Copolymers in which the butadiene is mainly incorporated with 1,2-addition. Due to the high proportion of vinyl groups, these copolymers, for. B. with oily Products, disadvantageous properties, such as high viscosities at relatively low Molecular weights and ease of crosslinking that make them suitable for some areas of application exclude.

Vinyl aromatic hydrocarbons, such as styrene, can be converted into benzene Solution with soluble catalysts made from nickel and / or cobalt compounds and Aluminum halides are not homopolymerized. Against it is it is known from German patent specification 1,156,986 that 1,3-dienes, such as butadiene, using catalysts made from cobalt and / or nickel-carbon oxide compounds or their substitution or.

Addition products and aluminum halides in aromatic solvents polymerize to form rubber-elastic products with a high proportion of 1,4-cis structure can, whereby monoolefins do not interfere.

It has now surprisingly been found that 1,3-diene copolymers can be used by copolymerizing 1,3-dienes with vinyl aromatic compounds in the presence aromatic solvent using catalysts from compounds of the Nickel and / or cobalt, which are soluble in aromatic solvents, under Addition of aluminum halides can be produced by copolymerization with the additional use of organoaluminum compounds and / or complexing agents for aluminum halides.

As a catalyst component containing nickel and / or cobalt preferably carbon oxide compounds of these metals or their substitution or Addition products of the type described in German Patent 1,156,986 and / or carbon oxide-free compounds of these metals in the Auslegeschrift 1 174 507, in which these metals are zero-valent, is used. Further There are also other compounds of nickel which are soluble in aromatic solvents and / or cobalt as a catalyst component in question, such as the soluble complexes the cobalt salts with polar compounds, such as. B. pyridine, quinoline, ethanol or Tetrahydrofuran, as well as chelate compounds such as nickel acetylacetonate, nickel acetoacetic ester and cobalt benzoylacetonate.

Suitable nickel and cobalt-carbon oxide compounds are above all Nickel tetracarbonyl, cobalt octacarbonyl, tetra cobalt dodecarbonyl and cobalt carbonyl hydrogen. Suitable substitution or.

Addition products of such carbon oxide compounds are, for. B. Nitrosylcobaltcarbonyl, Diphenylacetylene-dicobalt-hexacarbonyl, bis-triphenylphosphine-nickel-dicarbonyl and acrylonitrile nickel bis (trio-tolyl phosphite). Instead of the above-mentioned nickel or Cobalt-carbon oxide compounds can also be compounds of the zero-valent carbon oxide Use nickel and cobalt of the type disclosed in Auslegeschrift 1174507. Examples are nickel- (O) -bis-acrolein, nickel- (O) -cyclododecatriene, Nickel-to-bis-cyclooctadiene and bis-triphenylphosphine nickel-tO) -cyclooctadiene.

Anhydrous aluminum chloride is particularly suitable as the aluminum halide and aluminum bromide.

Suitable complexing agents for aluminum halides are in general those compounds which have lone pairs of electrons, e.g. B. a number of connections the elements of V. and VI. Main group of the periodic table of the elements, such as special of nitrogen, sulfur and oxygen.

Ammonia and amines such as diethylamine, tripropylamine, N-phenyl-ß-naphthylamine, N-cyclohexyl-N, N-diethylamine, N, N-dimethylaniline, heterocyclic Compounds like pyridine, quinoline, morpholine and phenthiazine. Suitable connections of sulfur are especially thiophene, diphenyl sulfide, thionaphthene and diethyl sulfide. Suitable compounds of oxygen are aromatic and aliphatic ethers, z. B. anisole and diisopropyl ether.

As organoaluminum compounds are suitable, for. B. triethylaluminum, Diethyl aluminum hydride, triisobutyl aluminum, diethyl aluminum chloride, dipropyl aluminum chloride, Ethyl aluminum dichloride and phenyl aluminum sesquichloride.

The quantitative ratio of the catalyst components can be within wide limits can be varied. In general, one works with a molar ratio of nickel or. Cobalt-carbon oxide compound to aluminum halides to form organoaluminum compounds or complexing agents for aluminum halides between 1: 0.2: 1 and 1--100: 50, preferably between 1: 0.5: 1 and 1:40:30.

The amount of catalysts used can vary within wide limits will. In general, 0.0001 to 0.5 parts of nickel or nickel are sufficient. Cobalt compound for 10 parts of monomers.

The catalysts are preferably used before the start of the polymerization produced by, for example, following the information in the German patent specification 1156 986, nickel or cobalt-carbon oxide compounds or their substitution or. Addition products with aluminum halides in aromatic solvents, if appropriate in a mixture with other solvents which are inert under the reaction conditions, at temperatures between 20 and 150 ° C, preferably between 20 and 70 ° C, some Time, e.g. B. 0.2 to 1 hour, mixes and the resulting solutions, if necessary after filtration, small amounts of complexing agents for aluminum halides and / or or organoaluminum compounds and optionally small amounts, e.g. B. about 0.1 to 1 percent by weight, based on the amount of 1,3-diene to be polymerized, Butadiene adds. The preparation of the catalysts and the copolymerization of the 1,3-dienes with the vinyl aromatic compounds are preferably used in the absence Carried out by moisture and oxygen by being practically dry and oxygen-free Protective gases such as nitrogen, noble gases or methane are used.

As 1,3-dienes that can be copolymerized by the process, there are mainly open-chain and cyclic hydrocarbons with conjugated ones Double bonds, the 1,3-diene structure wholly or partly in a cycloaliphatic Ring may be in question. Suitable are e.g. B. butadiene (1, 3), isoprene, 2,3-dimethylbutadiene (1,3), 2-ethylbutadiene (1,3), pentadiene (1, 3), cyclopentadiene, hexadiene (2, 4), Cyclohexadiene (1, 3), octatriene (1, 3,6) and 3-methylheptatriene (1, 4,6). Are preferred except Butadiene- (1, 3) open-chain 1,3-dienes with 5 to 7 carbon atoms. The 1,3-diene can also be mixed with monoolefins, such as ethylene, propylene and butene, as starting material be used because aliphatic monoolefins are not incorporated to any significant extent will. Suitable are e.g. B. also C4 hydrocarbon mixtures, as they are in pyrolysis of hydrocarbons. These contain up to 50% butadiene (1, 3) in addition to monoolefins, such as butene (1), butene (2) and isobutene, and paraffins.

The suitable vinyl aromatic compounds can be carbocyclic or heterocyclic aromatic ring system, such as a benzene, naphthalene, or thiophene Pyridine ring. For example, styrene, x-methylstyrene, 1-methylstyrene, 2-methylstyrene, 1,3- and 1,4-divinylbenzene, oc-vinylnaphthalene, Propylene styrene, vinyl thiophene, vinyl pyridines, 4-methoxystyrene, m-dimethylaminostyrene and 2-chlorostyrene. Styrene is preferred.

The quantitative ratio of the monomers to one another can be in the new Process can be varied within wide limits. In general, 100 Parts by weight 1,3-dienes 0.5 to 70, preferably 5 to 30 parts by weight of vinyl aromatic Links.

The copolymerization according to the invention becomes more aromatic in the presence Solvent carried out.

The better they are, the more suitable they are for the process dissolve the resulting polymers. They can also be mixed with aliphatic Hydrocarbons are used. Suitable are e.g. B.

Toluene, benzene, chlorobenzene, tetrahydronaphthalene, ethylbenzene or Mixtures of aromatic solvents and aliphatic hydrocarbons, z. B. from benzene and cyclohexane or from toluene and heptane. The amount of aromatic Solvent can be varied within wide limits. In some cases your The amount must be very small in relation to the amount of monomers. In general 20 to 80, preferably 40 to 60 percent by weight are used.

The interpolymerization can generally be carried out at temperatures of -50 to + 120 ° C, preferably from 10 to + 80 ° C, are carried out, with pressures of Normal pressure up to 20 atmospheres can be used. Higher pressures or pressures below Normal pressure are possible, but generally do not offer any advantage.

The process can be carried out batchwise or continuously work. In the case of a discontinuous procedure, for example, the benzene can be used Present the prepared catalyst solution in the reaction vessel, if necessary with further Dilute the solvent and add the vinyl aromatic monomer. Afterward the 1,3-diene can then optionally be introduced with cooling. Particularly beneficial the inventive method can be carried out continuously by one corresponding reaction vessel, the monomers and the catalyst solution at the same time supplies in the desired proportions.

The process according to the invention generally results in viscous ones Solutions of the copolymers. The catalyst can be reduced by careful addition Amounts of Lewis bases, e.g. B. ethers, ketones, amines, alcohols, ammonia, water or mixtures thereof, are decomposed. The mixed polymers can be extracted from the solutions optionally after separating off insoluble catalyst residues in a conventional manner, for. B. by evaporation of the solvent or by precipitation by means of larger quantities Methanol. For the production of completely ash-free copolymers can the inorganic catalyst residues from the polymer solution with substances, in which the inorganic constituents are readily soluble, e.g. B. with acidified Water, extract.

The process is also notable when using very small amounts of catalyst by high space-time yields, and one obtains polymers that are also without expensive Cleaning are only slightly contaminated by catalyst residues.

The average molecular weight of the copolymers obtained is depending on the catalyst concentration, the catalyst composition, the monomer ratio, the solvent used and the conversion or viscosity of the reaction solution.

In general, the resulting, mostly oily copolymers have average molecular weights of about 500 to 10,000, those with viscosities at 20 ° C from about 102 to 2 107 cP the character of thin oils up to very have viscous, rubber-like substances.

The polymers, for example from butadiene and styrene, have a previously unknown structure.

More than 95% of the butadiene is in the 1,4-position in the copolymer before, with the double bonds being built predominantly in the cis configuration. That Partly, styrene is polymerized into the chain, and partly isolated, statistically randomly in the form of blocks with up to six or more styrene units.

Depending on the polymerization conditions, however, up to 50 Percentage by weight of the polymerized styrene in the form of α or -styryl groups are present. The incorporation of styrene in high polymer copolymers in the form of terminal styryl groups is based on a novel principle of copolymerization Formation of interesting products due to the terminal reactive styryl groups further implementations are accessible.

The copolymers prepared according to the invention are suitable for many technical purposes, e.g. B. as a plasticizer for natural and synthetic Rubber and ethylene-propylene rubber, for the production of curable by crosslinking Films, coatings and molding compounds and as additives to oils to be dried. Furthermore are the oily copolymers are good viscosity index improvers for mineral oils with high shear strength.

The copolymers obtainable by the new process can in a simple manner by heating with oc-, p-unsaturated acids and / or their Anhydrides, esters, amides and imides, for example with maleic anhydride and Maleic acid diethyl ester and vinyl sulfonic acid esters. into valuable intermediates or paint raw materials are transferred. By hydrogenating the oily copolymers high quality hard waxes can be produced whose sulfonation products z. B. can be used as detergents.

The parts given in the following examples are parts by weight. The parts by volume given therein relate to the parts by weight like the liter to the kilogram. The K values given therein were after H. Fikentscher, Cellulose Chem., 13, p. 58 (1932), the molecular weights were determined in benzene Solution with a vapor pressure osmometer from Mechrolab Incorp. certainly.

Example 1 0.53 parts nickel carbonyl, 3 parts sublimed aluminum chloride and 500 parts of benzene, which is practically free of traces of water and oxygen Stirred for 1 hour at 50 ° C. with exclusion of air.

The mixture is allowed to cool to 30.degree. C., 7.4 parts of N-phenyl naphthylamine are added and decanted the catalyst solution into the polymerization vessel with the exclusion of air, where it is mixed with 500 parts of n-hexane.

After adding 400 parts of styrene it becomes gaseous. Butadiene- (1, 3) introduced rapidly into the reaction vessel, the temperature being approximately 10 to Rises to 50 ° C for 15 minutes. The temperature is maintained during the further introduction of butadiene by cooling to 50 ° C., up to a total of about 800 parts of butadiene is allowed to react for a further 1 hour with stirring and decomposes the catalyst by adding a mixture of 20 parts of acetone and 20 parts of benzene.

: After a few minutes, a mixture of 20 parts of methanol is added and 20 parts of benzene. The polymer solution is then poured into the polymer solution for a further 10 minutes gaseous ammonia initiated. Separated catalyst residues are separated and the solvent is distilled off from the clear solution. From the as distillation residue obtained oil are 2 hours at 150 ° C and 10 Torr in a rotary evaporator volatile components evaporated.

760 parts of a yellow-brown, clear, thin liquid oil are obtained the K value 13.9, the average molecular weight 700.9.2 percent by weight of jB-styryl groups and has 0.8 weight percent α-styryl groups. It has a viscosity of 530cP at 20 ° C and the iodine number 576.

Its double bonds are 76% in 1,4-cis and 22% in 1,4-trans structures and 2 0/0 in vinyl groups.

The copolymer contains 28 to 30 percent by weight of styrene as polymerized units.

By extraction for 6 hours with methanol, 16.7 percent by weight of a brownish, clear oil can be extracted from the copolymer. A yellow, clear oil remains as the residue. The two components have the following key figures: Extract residue K value ................ 7 15 Molecular weight ....... 352 1500 Styrene content in weight percent 60 26 ß-styryl content in Weight percent ...... 31 4.6 Iodine number 669 453 EXAMPLE 2 100 parts of benzene and 9 parts of freshly distilled styrene dried over aluminum oxide are placed in a stirred vessel with a capacity of 600 parts by volume, and about 6 parts of sweet butadiene are introduced into the mixture. A catalyst solution heated to 40 ° C. is then added and immediately thereafter about 50 parts of liquid butadiene per hour are introduced, the reaction temperature being kept at about 50 ° C. with cooling.

The catalyst solution is prepared in the following way: To 1.1 Parts of anisole which are practically anhydrous and air are given 0.62 parts of anhydrous aluminum chloride and 0.068 part nickel carbonyl. The mixture is stirred at 40 ° C. for about 20 minutes and then diluted with 2 parts of benzene.

In just under 3 hours at 50 to 55 ° C, a total of 161 parts become liquid Butadiene and at the same time 22.6 parts of styrene were added continuously. Within 7 hours the pressure falls from 1.4 to 0.1 atm. The mixture is left with stirring for 16 hours react further, are a mixture of 5 parts of acetone and 10 parts of benzene and after about 30 minutes 1 part slaked lime and then a mixture of 3 parts Methanol and 7 parts of benzene are added and the catalyst residues are separated off. After evaporation of the solvent and addicts proportions, you get 179 parts of a light yellow, clear oil, which has the K value 32.6, the average molecular weight 3400 and at 20 ° C the viscosity has 30 180 cP. The oily copolymer contains 11 percent by weight Polymerized in styrene. 84% of its double bonds are in groupings with 1,4-cis structure, 15% in those with 1,4-trans structure and 1% in Vinyl groups.

Example 3 150 parts of anisole are used at 40 ° C. to prepare the catalyst mixed with 82 parts of sublimed aluminum chloride. After all aluminum chloride Has gone into solution, 9 parts of nickel carbonyl are added, whereby the color the solution changes from dark green to yellow-brown.

300 parts of benzene and 50 parts are freshly mixed in a stirred vessel distilled styrene and saturates with gaseous butadiene at room temperature. then 4 parts of the fresh catalyst solution are added and then gaseous Butadiene initiated at 50 ° C. At the same time, 500 parts of styrene are left continuously run up to the end of the butadiene introduction.

After about 3 hours, a further 4 parts of catalyst solution are added and the polymerization after 5 hours by sequentially adding first one Mixture of 5 parts of acetone and 10 parts of benzene and, secondly, a mixture terminated from 5 parts of methanol and 10 parts of benzene. Then it is five times extracted with 2000 parts of water and separated the oil phase. The fleeting ones Fractions are separated from the oil phase, as indicated in Example 1.

663 parts of a yellowish, very viscous, strongly adhesive material are obtained Oil that has the K value 18.5, the average molecular weight 1900 and at 100 ° C the viscosity Has 3120 cP. It contains about 59 percent by weight of styrene polymerized. The double bonds of the copolymer are 48% in molecular parts with 1,4-cis- and 41% with 1,4-trans structure and up to 14 "/ in vinyl groups. The copolymer contains Styrene blocks with a sequence length of at least six styrene units.

Example 4 A mixture of 500 parts of benzene is added to a stirred vessel and 50 parts of freshly distilled α-methylstyrene with butadiene at room temperature saturated.

8 parts of the freshly prepared catalyst solution given in Example 3 are added and passes in gaseous butadiene with vigorous stirring in a rapid stream, whereby the temperature is kept at 50 to 55 ° C and continuously 150 parts of z-methylstyrene and after 2 hours a further 4 parts of catalyst solution are added. After 5 hours the introduction of butadiene is ended. The reaction is allowed to continue for 30 minutes and it is decomposed the catalyst and isolate the copolymer, as indicated in Example 1. 655 parts of yellowish, low-viscosity oil are obtained, which is 24 percent by weight of o [-methylstyrene] Contains polymerized, the K value 24.8 and at 20 ° C the viscosity 5700 cP. 79% of its double bonds are in groups of 1, 4-cis and 19 "/ in Groupings with 1,4-trans structure and 2% in vinyl groups.

Claims (1)

Claim: Process for the production of 1,3-diene copolymers by copolymerization of 1,3-dienes with vinyl aromatic compounds in the presence aromatic solvent using catalysts from compounds of the Nickel and / or cobalt that are soluble in aromatic solvents, whereby the copolymerization is carried out with the addition of aluminum halides, d a it is noted that the copolymerization with additional Use of organoaluminum compounds and / or complexing agents for aluminum halides is carried out.