DE1160186B - Process for the production of rubber-like polymers of butadiene - Google Patents

Description

There are already numerous processes for the polymerization of 1,3-butadiene with the aid of organometallic Known catalysts. Depending on the catalyst used, the ones obtained differ Polymers in their steric structure, d. H. in the manner of linking the monomer units. With lithium catalysts, for example, butadiene polymers are obtained whose monomer units are approximately 50% in 1,4-cis-, 40% in 1,4-trans- and zu 10% are linked in the 1,2-position. Butadiene polymers with over 90% cis-1,4 linkages one with titanium tetraiodide-containing mixed catalysts and with cobalt-containing mixed catalysts. Regardless the major difference in steric structure is the technological behavior of these polymers partly very similar. All of the butadiene polymers described so far show as raw material poor film strength. As a result of the low inherent tack of the raw materials, the polymers have a tendency when rolling within wide temperature ranges to form crumbs, so that the Manufacture of vulcanizable mixtures from these polymers under technical conditions causes considerable difficulties and the mixtures have a poor filler distribution.

Due to the processing difficulties mentioned, it is not possible to use mixtures based on of pure polybutadiene on an industrial scale. The types of polybutadiene described so far are only blended with natural rubber or styrene-butadiene copolymers as well as synthetic cis-1,4-polyisoprene can be processed, which makes the properties characteristic of polybutadiene partly worsened again.

It has now been found that polybutadienes can be obtained without blending with other elastomers or other corresponding auxiliary materials can be processed into products with good technological properties are, can arrive when using catalysts that are obtained by reacting a) titanium tetrachloride with b) iodine monochloride and / or iodine monobromide or iodine and bromine or mixtures of iodine and Bromine with more than 30 mol percent iodine and c) an aluminum alkyl compound have been obtained, the proportions of the components being chosen so that there is 1 mol of titanium tetrachloride 0.5 to 6 mol of halogen compound or halogen mixture and 1 to 20 mol of alkylaluminum compound can be used. These mixed catalysts are used in such concentrations that to 100 parts by weight Butadiene 0.015 to 5, preferably 0.03 to 2 parts by weight of titanium tetrachloride are present.

Method of manufacture

of rubber-like polymers

of butadiene

Applicant:

Paint factories Bayer Aktiengesellschaft,
Leverkusen

Dr. Nikolaus Schön, Leverkusen,

and Dr. Josef Witte, Cologne-Stammheim,

have been named as inventors

Alkylaluminum compounds are understood to mean compounds of the general formula A1R'R "R '", in the R'R "R '" aliphatic or cycloaliphatic hydrocarbon radicals having 1 to 12 carbon atoms mean and in which R 'and R "can also be hydrogen.

Aluminum trialkyls as well as mono- or dialkylaluminum hydrides can thus be used will. Preferably there are alkylaluminum compounds containing 2 to 4 carbon atoms Alkyl radicals into consideration.

Examples of alkylaluminum compounds suitable for the preparation of the catalyst combinations to be used according to the invention are: A1 (C ₂ H ₅ ) ₃ , Al (iso-C ₄ H ₉ ) ₃ , Al (nC ₃ H ₇ ) ₃ , Al (iso-C ₈ H ₁₇ ) ₃ , Al (nC ₁₂ H ₂₃ ) ₃ , Al (ISO-C ₄ H ₉ ) H ₂ .

Catalysts which are particularly suitable for the preparation of the polymers according to the invention are obtained if the proportions of the components are chosen so that 0.5 to 6 moles of iodine monochloride or iodine monobromide or 0.5 to 6 moles of a mixture of bromine and iodine are used per mole of titanium tetrachloride used with more than 30 mole percent iodine and a molar amount of alkyl aluminum compound, which is determined by the apparent from the following relationship borders: a = (b + 7) ± 6, where a is the molar amount of the alkylaluminum compound and b is the amount of iodine monochloride or iodine monobromide or used Mixture of bromine and iodine with more than 30 mole percent iodine, expressed in moles.

The butadiene polymers produced according to the invention show in the raw state in contrast to

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Polybutadienes known to date use a similar method to keep prepared catalyst solutions at 30 to 50 ° C as natural rubber. They have a paraffin oil or hydrogenated diesel oil that was previously not present in the polybutadiene types known to increase the activity of the catalysts, as well as a higher inherent tack and, in their raw state, boiling aromatic hydrocarbons have proven to have a film strength similar to that of natural rubber. The aluminum compounds can be used as suitable solvents for the alkyl On a roller and in the internal mixer, because when the polymers according to the invention are used, they can be processed very well; Like solvents a reaction of the alkyls They show an aluminum compounds with air and moisture excellent rolled skin formation over a wide temperature range, while the known polybutadiene types have been largely prevented so far Range from -40 to +48 ⁰ C can be carried out. Show fur formation. A temperature range from 0 to 50 ° C. is preferred.

The high film strength is also evident. The polymerization can take place at normal, reduced at the unvulcanized or increased pressure produced from the raw material. Further based mixtures. From the 15 according to the invention, the polymerization can be carried out in the presence of an inert polymer Prepared mixtures show gases such as nitrogen, helium or argon or geallen technically occurring temperature ranges, if necessary under the pressure of the steam of the excellent filler absorption, filler material and solvent used, division and high tack. With the catalysts of the invention can

The excellent properties of after the 20 butadiene polymerization both discontinuously as Polybutadienes produced in the present process can also be operated continuously. Particularly come into their own in particular because they are suitable for the discontinuous mode of operation Do not mix this polybutadiene with other elastomers must be cut. Allow moisture exclusion. The continuous

The monomeric butadiene used should no longer be used. than 0.01% 1,2-butadiene and not more than 0.01 up to the further polymerization vessels Contains 0.015% acetylenes. As is well known, low can also be in a suitable pipe system Quantities of water can be carried out during the polymerization with titan.

mixed catalysts containing an advantage. Larger The work-up of the polymers, the deactiva-

Amounts of such substances that are with the catalyst 30 and possible removal of the catalyst react and make this ineffective, such as water, z. B. by treatment with alcohols, water, Oxygen, carbon dioxide as well as 1,2-butadiene and acetone or mixtures of these substances, given acetylenes must in the process according to the invention if with the addition of organic and / or inorganic can be eliminated prior to polymerization or achieved by means of acids and bases. The increased addition of alkylaluminum compound must be such that the amount of these substances is still not beet, so that the composition of the no precipitation of the polymer occurs and the precipitation Catalysts according to the invention remains unchanged. only through subsequent addition of a larger amount As a solvent for the production of the catalysis of a lower aliphatic alcohol, such as methanol, Sators and for the implementation of the polymerization ethanol, isopropanol, is effected. Furthermore can Especially aliphatic and cycloaliphatic 40 stabilizers and antioxy hydrocarbons are used in the course of processing, but also aromatic carbons, such as phenyl - ^ - naphthylamine, N, N'-diphenyl hydrogen or mixtures thereof, e.g. B. p-phenylenediamine, di-tert-butyl-p-cresol, di-tert-butane, Hexane, octane, petroleum ether, ligroin, hydrogenated butyl hydroquinone, tris (nonylphenyl) phosphite, and more Diesel oil, cyclohexane, methylcyclohexane, benzene, buffering substances such as calcium stearate, Toluene, xylene or methylnaphthalene. For the ver 45 are added.

The same purity applies to the solvents used. Paraffinic and naphtha can also be used.

conditions as for the monomeric butadiene. thenic mineral oils as well as phenol aldehyde resins and

The catalysts are prepared in ali-alkyd resins and low-molecular-weight butadiene polypatic resins and / or aromatic solvents, merisate added in the course of work-up how to carry out the polymerization in 5 °.

Comes into consideration, with exclusion of air and in the following examples are given

Moisture by adding the alkylaluminum parts by weight, formation with the halogen compound or halogen example 1

mixture and then the titanium tetrachloride

or by adding the titanium tetrachloride with the 55 In a stirred vessel, the alkylaluminum compound is reacted with the exclusion of air and then the and moisture in 250 parts of cyclohexane, a cata-halogen compound or halogen mixture is added. According to the preferred procedure, however, 0.28 part of titanium tetrachloride and 0.33 part of titanium tetrachloride are reacted with the halogen compound or iodine monobromide in the form of a hexane solution and with the halogen mixture, and then 60 2 Adds 95 parts of aluminum triisobutyl. The alkyl aluminum compound is cooled and added. At -5 to the black-brown Katalyastorlösung to 0 ° C. and +50 ⁰ C to obtain the catalyst in the form of a subsequently added a solution of 100 parts of butadiene in black-brown colored solution or suspension. 250 parts of cyclohexane. The beginning of the polymer

When using aromatic solvent sation soon shows up by increasing the temperature it proves to be expedient to put the catalysts at 65 and increasing the viscosity of the solution. By setting temperatures from -5 to +10 ⁰ C. If the internal temperature is kept at 10 to 25 ° C., the catalysts prepared in this way have a high degree of polymerization after 10 to 12 hours. The rate of polymerization. Brief heating of the polymer solution is first mixed with a little methanol,

to which 3 parts of a phenolic stabilizer and two parts of an amino alcohol are added, stirred and then precipitated by the addition of increased methanol. The polymer is dried at 50 to 60 ° C. in vacuo. 53 parts of a polybutadiene are obtained which is readily soluble in toluene and has good intrinsic tack and high film strength. The polymer has a structure with 60.1% ^c is-1,4 linkages and an η value of 3.1.

Examples 2 to 5

A number of further polymerizations are carried out under the conditions mentioned in Example 1, however, the monomeric butadiene is added in 300 to 350 parts of cyclohexane. Instead of Iodine monobromide is also used for catalyst production. The duration of the Polymerizations take an average of 7 to 10 hours.

example Butadiene
Parts TiCl ₄
Parts JBr
Parts Al (iC ₄ H ₉ ) ₃
Teüe ? 7 value yield cis-1.4 Structure, ° /
trans-1,4 ι
1.2 2 140 0.19 0.96 1.98 2.8 69 71.7 25.3 3.0 JCl
Parts 3
4th 150
160 0.26
0.27 0.65
0.65 2.01
3.1 1.3
2.3 On oo
VO O 63.1
68.0 27.8 9.1 AI (C ₂ Hs) ₃
Dear 5 140 0.185 0.76 1.15 1.7 91 60.9 29.7 9.4

The polymers obtained have good film strength and tack.

Example 6

Under inert conditions, a catalyst solution is prepared in 550 parts of toluene (water content 0.003 to 0.005%) at -5 ° C by adding 0.142 part of TiCl ₄ , 0.3 part of iodine monobromide and 1.09 part of Al (iC ₄ H ₉ ) ₃ in the mentioned order. 100 parts of butadiene are passed into the solution. At a polymerization temperature of 5 to 10 ^{° C., after 8 hours, β} in polybutadiene is obtained in a yield of 100%, which is worked up as in Example 1, but 3 parts of abietic acid are added instead of ethanolamine.

The polymer is similar in its properties to the natural rubber raw material, it is elastic, has a good tack and can be rolled well at 80 and 120 ⁰ C. ?? - value = 2.2.

Structure: cis-1,4: 82.1%; trans-1,4: 9%; 1.2: 8.9%.

Example 7

As in the example, ^{a catalyst solution is prepared at 0 °} C. by adding 0.145 parts of TiCl ₄ , 1.1 parts of Al (iC ₄ H ₈ ) ₃ and 0.3 parts of JBr in the order mentioned. At a temperature of 5 to 10 ^° C., 85 parts of polymer are obtained after 8 hours from 100 parts of butadiene under the same working-up conditions. Compared with the polymer obtained in Example 6, the tack is lower and the film strength is higher.

r / value: 3.0; cis-1,4 content: 79%.

Example 8

As in the example, ^{a catalyst is prepared at 0} ° C. from 0.31 parts of JBr, 1.11 parts of Al (iC ₄ H ₉ ) ₃ and 0.145 parts of titanium tetrachloride, which are reacted with one another in the order mentioned. After 8 hours at 5 to 10 ^° C., 65 parts of polybutadiene are obtained with a 77 value of 2.0 and a structure of 78.5% cis-1,4 linkages. The raw material properties are the same as the polymer obtained in Example 6.

Examples 9 to 16

A series of further polymerizations are carried out under the conditions of Example 6. Iodine monochloride, iodine and bromine are also used in the production of catalysts. The polymers obtained show good tack and high film strength and have a good rolled sheet formation on at 8O ⁰ C.

example Butadiene
Parts TiCl ₄
Parts JBr
Parts AKi-C ₄ Hs) ₃
Parts yy value yield
° / o cis-1.4 Structure, ° /
trans-1,4 1.2 9
10 ^a ) 160
125 0.28
0.18 0.33
0.41 1.98
2.0 1.8
2.3 71
100 64.1
82.3 30.8
7.4 5.1
10.3 AlH ₂ (IC ₄ H ₉ )
Parts 11 *) 120 0.19 0.41 0.86 1.8 97 74.3 20.9 4.8

^a ) Polymerization time 6 to 7 hours at 5 to 10 ⁰ C.

Butadiene
Parts 7th J ₂ / Br ₃
Parts 0.27
0.27
0.27 0.33
0.65
1.14 AKtC ₄ He) ₃
Dear j? value yield
° / o 8th Structure, ° /
trans-1,4 1.2 example 100 TiCl ₄
Parts 0.38 to 0.24 3.4 2.4 80 cis-1.4 - - 12th 0.27 JCl
Parts 0.26 0.16 69.1 160
150
180 2.38
2.4
2.58 1.9
1.5
1.6 90
95
100 22.3
15.8 8.0
10.3 13th
14 ")
15 ') Al (C _a H ₆ ) _s
Parts 69.7
73.9
73.0 130 0.57 2.8 75 29.1 3.0 16 67.9

^b ) Polymerization time 5 to 6 hours at 2 to 7 ° C.

^c ) Polymerization time 8 to 9 hours at 5 to 10 ° C.

Example 17

A larger amount of polybutadiene is produced according to Example 6 and in its raw material properties as well as the properties of the vulcanizate compared with conventional types of polybutadiene.

a) Raw material properties

30th

35

40

Invention
according to
manufactured
Poly
butadiene Poly
butadiene with
TiJ ₄ ZAlR ₃ Poly
butadiene with
Li-butyl manufactured manufactured plasticity (Mooney 38 ML 4 ', 100 ° C) 42 31 Rolling behavior smooth at 20 ° C FeU smooth Crumbs smooth fur . at 80 ° C fur Crumbs Crumbs smooth at 100 ° C fur Crumbs Crumbs smooth at 120 ° C fur Crumbs Crumbs

b) Production of a tread compound

Mix recipe parts

Polybutadiene 100.0

Stearic acid 1.5

Zinc oxide 5.0

Highly abrasion-resistant furnace black 48.0

Plasticizers (aromatic mineral oil) .... 10.0

Tackifier (rosin) 5.0

Anti-fatigue agents

(p-phenylenediamine derivative) 0.75

Anti-aging agents

(Phenyl-a-naphthylamine) 0.75

Paraffin 0.6

Sulfur 1.8

Vulcanization accelerator (N-mercaptobenzothiazole

sulfenamide) - 0.9

Invention Polybutadiene according to TiJJAlR ₈ manufactured Polybutadiene 25 to 35 Roll temperature, ° C 60 to 70 mixture Mixing behavior very good crumbles and falls from the Roll off, Soot pick-up very bad moderate Filler distribution Well Confectionery stickiness (1 = very sticky, 5 5 = not sticky) .. 2 to 3 dull, uneven Appearance of the fur smooth Vulcanization rate speed, minutes (optimal Vulkani sation at 40 atm (= 151 ° C) volcanic 30th meter measurement) 18th

c) Properties 5o of the vulcanizates Polybutadiene TiJJAlR ₃ 55 tensile strength, 140 kg / cm ² 530 Strain, % 60 Hardness (Shore) 51 Rebound resilience .. Notch toughness 14th (kg abs. 4 mm) Dynamic 53 warming 65 Goodrich Flexometer ° C after 25 minutes Abrasion resistance 43 DIN (mm ⁸ ) Invention according to manufactured Polybutadiene 156 610 57 49 19th 52 13th

Claims (3)

Patent claims: 1. A process for the preparation of rubber-like polymers of butadiene by polymerization of butadiene in the presence of iodine-containing organometallic mixed catalysts, characterized in that such mixed catalysts are used, which by reacting 1 to 20 moles of alkylaluminum compound with 1 mole of titanium tetrachloride in the presence of 0.5 to 6 moles of iodine monochloride or iodine monobromide or a mixture of bromine and iodine with more than 30 mole percent iodine have been obtained in such a concentration that 0.015 to 5, preferably 0.03 to 2 parts by weight of titanium tetrachloride are present for 100 parts by weight of butadiene. 2. The method according to claim 1, characterized in that one uses catalysts which have been obtained by using 0.5 to 6 mol of iodine monochloride or iodine monobromide and a molar amount of alkylaluminum compound, the limit of which is determined by the relationship a = (b + 7) ± 6, where α is the molar amount of the alkylaluminum compound and b is the amount of iodine monochloride or iodine monobromide expressed in moles. 3. Process according to Claims 1 and 2, characterized in that the alkyl aluminum compounds are used Aluminum trialkyls or mono- or dialkyl aluminum hydrides having 2 to 4 carbon atoms containing alkyl radicals used. Considered publications:
German Auslegeschriften No. 1 104 118, 1 182 834. © 309 770/506 12.63