DE1923998C - Process for the polymerization of olefins - Google Patents

Description

that a certain transition metal oxide carried on where R again represents an alkyl group with 1 to 10 carbon

a carrier with a special compound lenstoffatomeii '. "" *

is combined. These compounds, in which R is a lower ¹ alkyl

The invention is based on the object, group means like a methyl or ethyl group,

a catalyst and thus a technically advantageous 5 are in contrast to conventional lower alkylaluminum

Adhesive process for the polymerization of olefins to form sodium compounds such as Triethylaluroinium beiNonr Λ-

find, where a catalyst is used, the temperature solid substances and have ehx low

an extremely high catalytic activity not only when there is a tendency to spontaneous combustion when standing

high temperature, but also at low temperature the air. These connections are accordingly

temperature. Furthermore, the present erio is suitable for convenient handling. Besides that

based on the task at hand, they are technically in common hydrocarbon solvents

advantageous process for the polymerisation of oils - very soluble. '

On the other hand, chromium oxide on a polymerizate obtained, even with a low refractory metal oxide as the carrier, can be freely selected as the catalyst temperature. 15 component, which consists of chromium oxide and a hhze object of the present invention is a stable metal oxide and which forms the catalyst for the polymerization of olefins with the aid of a pentaalkylsiloxyalane, using chromium oxide-supported catalysts at a temperature . Such refractory metal oxides temperature in the range between room temperature and are, for example, silicon dioxide, aluminum oxide, 2J0 C and a pressure in the range between normal ao zirconium oxide and thorium oxide. As the person skilled in the art is familiar with pressure and 100 atmospheres in the presence of catalysts in this technical field, Ksatoren which is characterized in that a mixture of these substances is used, for example a silicon catalyst combination, which are used from .Aluminium oxide. Even though these ι) substances can be carried on a heat-resistant metal oxide which are commercially available nem chromium oxide and 25, silicon dioxide and silicon dioxideb) a pentaalkylsiloxyalane of the general formula aluminum oxide are preferred. In general, finely distributed substances with an average particle size of SiOAlR of less than 10 microns because of their high ³ * polymer! Dns activity particularly preferred. From where the symbols R each represent the same or different atoms, finely divided silicon dioxide, such as various alkyl groups with 1 to 10 carbon atoms in the form of various products on the market, is particularly recommended.

consists. Chromium oxide can easily be applied to such a carrier - any alkyl groups with 1 to 10 carbon can be applied by having a suitable carbon atom in the compound of the general chromium compound on the metal oxide in the desired formula R ₃ SiOAlR, where R is un - Way, for example by impregnation, distillation, depending on an alkyl group with 1 to 10 carbon sublimation or a similar process referred to atoms applied. Accordingly, the and the connection can then be burned. Suitable different substituents R naturally identical chromium compounds are, for example, oxides, halo or different alkyl groups. Compounds, 40 genides, oxyhalides, phosphates, sulfates, oxalates, in which the substituents R are the same alkyl alcoholates and organo-compounds of chromium, are, for example, pentamethylsiloxy, of which chromium trioxide, chromium sulfate and t-butylalane, pentaethylsiloxyalane, pentabutylsiloxyalane , Penchromatic are particularly suitable. Activation of Tahexylsiloxyalane and Pentaoctylsiloxyalane. As examples catalyst component is prepared by calcining examples of compounds in which the substituents R acts 45, after these chromium compounds are at ^r for each different Alkylg uppen, said heat-resistant metal oxide are applied wor-Si-trimethyl-Al-diäthylsiloxyalan, Si-triethyl -Al-d ;. the goods. The chromium content is preferably methylsiloxyalane, Si-triethyl-Al-dibutylsiloxyalane and the range from 0.1 to 5 percent by weight, referred to as Si-tributyl-Al-diethylsiloxyalane. Of these, the carrier.

Compounds are preferred those that have lower 5 ° Activation by calcination is in the Alkyl groups such as pentamethylsiloxyalane are usually carried out in the presence of oxygen

and Si-trimethyl-Al-diethylsiloxyalane. however, it can also be used in the presence of an inert gas

It is known that such pentaalkylsiloxyalanes are carried out or under reduced pressure,

according to customary methods according to the following As a rule, the calcination is carried out at a temperature

Reaction formulas can be prepared: 55 temperature between 300 and 1200 ° C, preferably tCO

and 1100 ⁰ C and very particularly preferably between

R ₃ SiOAlX, + 2MR> R ₃ SiOAlR, + 2MX (1) 500 and 100O ⁰ C for a period of a few Minutes to several \ ϋ hours, vomigsvrcise R ₃ SiOM + XAlR,> R ₃ SiOAlR, + MX (2) carried out from 10 minutes to 10 hours.

60 The catalyst is made from this catalyst

in which R is formed in each case for an alkyl group with 1 to 10 carbon components. The relationship between the KaUi-

lenstoffatomen, M means an alkali metal and lysator components is usually in the case of calibration

X is a halogen atom (Journal of Organo-metallic from 0.01 to 500 expressed as Si / Cr (Aiom-Ver Chemistry.Bd. 1 [1963], p. 28). It is also possible to hold). From an industrial point of view

these compounds according to the following reaction 63, however, the range 0.1 to 50 is particularly preferred,

Synthetic manufacture equation: The manufacturing process for the catalyst is

not particularly critical. It can be done like this

R ₃ SiOH - (- AlR ₃ > R ₃ SiOAlRj + RH (3) are that both catalyst components before the

5 \ 6

Polymerization reaction interacting with one another - as already stated - the permeability or that both components in the form of leading the polymerization reaction in sufficient a mixture introduced into the reaction system is allowed to lie even at low temperature will. These components can of course be used in the polymerizates obtained in the polymerization separation added to the reaction system. Extra-5 action system in the form of an anscWammung. There are also other components in the reaction system. In this way, the viscosity of the Components are present. Polymerization system prevented. Therefore, the

The polymerization of the olefins is carried out with the concentration of polymers in the polymerization of the catalyst obtained in this way. system are increased, for example to examples for the purposes of the present invention io 30 ° / ₀ or even more. This has a number of usable olefins are ethylene, propylene, butene-1 niche advantages result -me a reduction, etc. It is also possible to subject a mixture of these olefins of the polymerization reactor to a reduction in a copolymerization. The poly "amount of circulating solvent, and a raerisationsreaktion Usually such Removing incidental reduction of the driving means, carried out in that the catalyst in an inert solvent i ₅ The following examples illustrate the invention, medium dispersed, the olefin is fed thereto, and the "" s ο ie I 1 mixture at a given temperature and a given pressure ^p is maintained. 10 g finely divided Si); umdioxid, average

The preferred inert solvents are particle size 300 Å, wuid ^ n in 40 ml of an aqueous

turns aliphatic hydrocarbons such as hexane, ao solution dipped in 0.20 g of chromium trioxide. Which he-

Heptane, octane and isooctane cycloaliphatic carbon haitene slurry was dried at 120 ⁰ C Hydrogen would be cyclopentane and cyclohexane and then at 800 ° C for 1 hour in one stream

aromatic hydrocarbons such as benzene and calcined by dry air to activate. the

Toluene. However, other solvents can also be used as the catalyst component (hereinafter referred to as

are used, which are usually referred to for the polyas »chromium oxide catalyst component«)

merization reaction can be used. The poly held 1 ° / “chrome.

The reaction reaction is carried out at a relatively low temperature and pressure. The temperature component according to the reaction equation (?) On temperature is in the range between room temperature produced in the following manner. After the air is in and 250 ⁰ C. The pressure is usually in the range of 30 in a 200 ml flask, with a stirrer between normal pressure and 100 atmospheres. This was allowed to have been displaced by argon gas. Conditions sufficient to conduct the polymerization in 100 ml of cyclohexane and about 11.4 g (0.1 mol) as desired. Add the polymeric ethylaluminum to the flask. Can then sationsverfahren according to the invention in the flask at 50 ⁰ C was maintained. On the upper part of the steam phase are carried out. In addition, a reflux condenser was attached to the flask, which was connected to a gas meter to allow hydrogen to be present in the reaction system. One of the openings to control the average molecular weight and openings of the flask was closed with a seal changing the physical properties of the obtained polymer, by means of a syringe inside the polymer. Since the hydrogen gradually increased to 9.0 g of the polymer 40 (0.1 mol) trimethylsilanol Si (CH,), OH over a period of about 1 hour, carefully adding conditions and learning the desired molecules became. The addition of the trimethylsilanol depends on the weight of the polymer, it is necessary to initiate a lively reaction, whereby it is possible to adjust the amount accordingly. gas escaped. The amount of gas evolved is about

The polymerization of the olefins is carried out in the above 2.3 l under normal pressure and temperature. besc'iii ^ benea way carried out. However, since the 45 After complete removal of trimethylsilanol for the method useful according to the invention, the reflux condenser was replaced by a distillation-catalyst by moisture and oxygen readily apparatus, and the major portion of cyclohexane is tntaktiviert, Inue _i sen the starting materials, was distilled off under normal pressure In the subsequent distillation under reduced pressure, the olefin, hydrogen and solvent were added to the polymerization system, and initially there would be a trace of low-boiling Korashes, worthily those that had previously been distilled off. This was followed by Si-Tri ~ were sufficiently purified. methyl-Al-diethylsiloxya'an as the main product

The 137 to 108 ° C / 6 mmHg. The yield was 14.5 g

The polymers are colorless, crystalline poly (83 ° / ₀ ). The obtained Si-trimethyl-Al-diethylsiloxy-

merisate of high density. They are suitable, for example. Immediately after distillation, alan was viscous

wise for use in molding process, especially oily substance, but it gradually crystallized,

Blow molding process. when left at room temperature.

As already stated above, the boiling point of the product was 107 to 108 ° C / the catalyst according to the present invention 6 mmHg or 135 to 140 ° C / 18 mmHg. an excellent high catalytic activity. When 60 In a 1 liter autoclave equipped with an electrodepolymerization of olefins using magnetic stirrer, 52 mg of the chromium oxide catalyst component prepared according to the present invention and 8.7 mg of catalyst were found a very (0.05 m mol) Si-trimethyl-Al-diethylsiloxyalane, such as great degree of polymerization activity not obtained according to the above method, only at high temperature but also at lower 65 along with 500 ml of a sufficiently dehydrated one Temperature, and the average molecular and deoxygenated n-heptane given. The remaining weight of the polymers obtained can easily be trolled through dry nitrogen in the autoclave. Since the method of ER had been displaced in accordance with, the mixture at 8O ⁰ C

heated. Ethylene was introduced into the autoclave until the total pressure reached 5 kg / cm ² . Heat evolved as ethylene was bubbled in and polymerization of the ethylene was observed. The polymerization was carried out for 1 hour under constant pressure, while the polymerization ^{temperature was kept at 80 °} C. and the total pressure at 5 kg / cm ² . This gave 123.7 g of a white powdery polyethylene which had an average molecular weight of 222,000. In this polymerization reaction, the rate of polymerization based on the chromium oxide catalyst component was 2370 g / g of the chromium oxide catalyst component · hour.

Example 2

The reaction was carried out similarly to that described in Example 1, except that the ethylene pressure was used were modified during the polymerization time as well as the polymerization time. The received The results are compiled in Table 1 below.

Table 1

The results obtained are shown in Table 3.

Table 3

Amount of (Atom- Polymerisation (CHj) ₃ SiOAl (C ₁ Hs) ₁ ratio) speed (mMnt) 0.05 (g EP / g cat * VIII IVI Ul I 0.1 Hours.) 0.0005 0.5 270 0.001 1 850 0.005 5 1,920 0.01 10 2.290 0.05 50 2,370 0.1 100 2,410 0.5 2,390 1 1,380

No. Ethylene
pressure
(kg cm ² ) Polymerization
time (minutes) Polymerization
speed
(g EP / g cat * hour) 1
2
3 5
10
20th
30th 60
30th
20th
10 2,370
4,530
8,920
13,300

* Kat - chromium oxide catalyst component.

Example 3

_ao B eis ρ ie 1 5

The, similarly as described in Example 1, prepared catalyst and n-heptane were in the The same quantities as they were used in Example 1 were placed in a 1 liter autoclave. the

* 5 temperature of the autoclave was raised to 8O ⁰ C, and "ine given amount of hydrogen was introduced into the autoclave with stirring while this temperature was maintained. Athyien was then introduced in such an amount that the pressure was increased by an additional 5 kg / cm ² . The polymerization was carried out at 80 ^° C. for a period of 1 hour under constant pressure, with ethylene being supplied in such an amount that the total pressure was maintained constant. The results obtained are shown in Table 4.

Table 4

The polymerization of ethylene was carried out analogously to the case of Example 1, but with the polymerization temperature was changed. The results obtained are summarized in Table 2.

Water loft
crowd
(kg / cm ¹ ) total
pressure
(kg / cm ² ) Polymerization
speed
(g EP / g cat
Hours.) average
liches
Molecular
Weight 0
2.5
5.0
7.5 5.0
7.5
10.0
12.5 2,370
2.530
. 2,470
2,610 222,000
112,000
77,000
56,000

Table 2 Example 6

Polarization Polymerization rate temperature (° C) (g EP / g Kat * ■ Sld.) 60 2.210 80 2,370 100 2.520 120 1.010 150 420

Kat = chromium oxide catalyst component (this designation also applies to the following tables).

Example 4

The polymerization of ethylene was carried out analogously to that described in Example 1, but with the amount of Si-trimethyl-AI'-diethylsiloxyaian such as indicated in table 3 changed wuide. The one with it 10 g each of different types of finely divided silica as shown in Table 5 were immersed in 40 ml of an aqueous solution of a given amount of chromium trioxide.

The slurries obtained were dried at 120C and at a given temperature activated for a given time in a stream of dry air. The chromium content of the chromium oxide catalyst components obtained are given in Table 5. The chromium oxide catalyst conv components were combined with Si-trimethyl-Al-diethylsiloxy alan, which is similar to that in the case game 1 had been made to zi the catalyst form. The polymerization of ethylene was carried out using the catalyst obtained under dei the same conditions as described in Example 1; accomplished. The results obtained are ii Table 5 given.

• tnn 41 n /

table

10

Heat resistant »
Metal oxide Content of Cr activation
temperature conditions
time Si / Cr
(Atomic ratio) Polymerization
speed (V.) ("C) (Hours.) (g EP / g quay * ■ hours) Silica ** 2.0 600 2 2.5 1,550 Silica ** 1.0 600 2 5 1,720 Silica ** 1.0 800 2 5 2.210 Silica ** 1.0 800 1 5 2,370 Silica ** 0.5 950 0.5 10 2.730 Silica ** 0.5 1000 0.5 10 2.050 Silica ** 1.0 800 1 5 1,750 Silicic acid * * ♦ 0.5 950 0.5 10 2,000

* Kat - chromium oxide catalyst component c.

** Very finely divided, highly porous silicon dioxide, average particle size 300 A. *** Silicon dioxide in submicroscopic fine distribution.

Example 7

Analogous to the production of Si-trimethyl-Al-diäfhylsiloxyalan according to Example 1 pentamethylsiloxyalane was prepared, but instead of the im Example 1 used triethylaluminum, the trimethylaluminum was used as the starting product. The boiling point of the pentamethylsiloxyalane obtained was 80 to 82 ° C / 11 mmHg.

The polymerization was carried out as in Example 1, However, the pentamethylsiloxyalane thus obtained replaces the Si-trimethyl-Al-diethylsiloxyalane was used. Thereby, 133.5 g of white powdery polyethylene with an average Obtained molecular weight of 238,000. Similar results were obtained when Si-trimethyl-Al-diisobutylsiloxyalane and Si-trimethyl-aldioctyl-siloxyalane were used.

Example 8

The catalyst was prepared similarly to that described in Example 1, and the solvent was added in the same amounts as in Example 1 to a 1 liter autoclave. The temperature of the autoclave was ^{heated to 80 °} C., and hydrogen was introduced with stirring up to a pressure of 2.5 kg / cm *. An ethylene-propylene mixture containing a small amount of propylene was then introduced with stirring until the pressure was increased by a further 5 kg / cm ¹ . The polymerization reaction was carried out for 1 hour at 80 ^c C under constant pressure, wherein the Athykn-propylene Genüsch was introduced in such an amount as to keep the total pressure at 7.5 kg / cm *. 118.0 g of white powdery copolymer were obtained in this way. An IR absorption spectral analysis of the copolymer obtained, which had been pressed onto a thin plate, showed that the copolymer was an ethylene-propylene copolymer having 2.8 branched methyl groups per 1000 carbon atoms.

An analysis of the vapor phase gases in the autoclave before and after the polymerization gave an average the following composition:

Ethylene 65 · /.

Propylene 2 · / _β

Hydrogen 33 / (percent by weight)

^ao B eis ρ ie 1 9

The catalyst was prepared in a manner similar to that described in Example 1. The solvent was in same amounts as used in Example 1 in

»5 put in a 1 liter autoclave. The temperature of the autoclave was raised to 80 ° C. and hydrogen was introduced with stirring up to a pressure of 3.0 kg / cm *. Then ethylene was passed in until the pressure dropped to liters 5 kg / cm. ^{1 was} increased. The polymerization reaction was carried out at 80 ° C. for a period of 1 hour under constant pressure, with ethylene being introduced in such an amount that the total pressure was kept at 8 kg / cm ¹ . As a result, 130.0 g became white

powdered polyethylene obtained. After the obtained polyethylene has been sufficiently dried various physical properties of the polymer were measured. Those given in Table 6 Results were thereby obtained.

Table 6

Physical Properties Measured
results Melt index * 1
Flow ratio * 2
Density * 3
First stretch strength * 4 0.29
151
0.965
262

* 1 Measured according to ASTM-D-1238.

• 2 Gewicts erltnis of Polyithyten that * at the same temperature of 190 ⁰ C (ausfliefit per Zeiteinhei wherein Scaerangskoefrhienten of 10 * dynes / cm or 10 * dynes / crn the coarser the ratio, the wider the molecu is largewichtsverteuung of Polymer.)

• 3 Measured according to ASTM-D-1248 (g / cm *).

* 4 Measured according to ASTM-D-638 (kg / cm *).

Comparative experiment 1 In a 1 liter antoclave, which is equipped with an eiektrc So magnetic stirrer is equipped, SOO η

sufficiently dehydrated and oxygen-free n-heptane and 250 mg of only the chromones

Catalyst component given. After the Lu!

verdifinj in the autoclave by dry nitrogen

'was required, the mixture was ^{heated to 8G a} C «rhitz

Then ethylene was introduced under pipes, un

the Porymerisat! on »r? action was 1 hour Uui under a constant total pressure of tOkg / cn

ii

carried out, 88.8 g of a white powdery powder Polyethylene were obtained, which has an average molecular weight of 23S,000. In this polymerization reaction, the rate of polymerization, based on the catalyst component, was 355 g EP / g cat hour

This result clearly shows that the catalyst according to the invention is excellent in terms of the effect on the rate of polymerization in comparison with the known catalyst.

Comparative experiment 2

The catalyst components and the same solvent as used in Comparative Experiment 1 in the same amounts as in Comparative Experiment 1 were placed in a 1 liter autoclave. The temperature of the autoclave was raised to 8O ⁰ C, and hydrogen was eingebitet in the stated amount. Ethylene was then passed in until the pressure * had risen ^{by a further 10 kg / cm 1.} The polymerization reaction was carried out at 80 ^° C. over a period of 1 hour under constant pressure, ethylene being introduced in such an amount that the total pressure was kept constant. The results obtained are shown in Table 7.

Table 7

A moderately low temperature and control of the molecular weight by means of hydrogen is much more difficult or less effective than according to the invention (cf. Example 5).
S.

Comparative experiment 3

In a 1 liter autoclave, the same catalyst component and the same solvent as in Comparative Experiment 1 were placed. The temperature of the autoclave was. ⁴ e increased to 80 ^° C., and hydrogen was passed in with stirring up to a pressure of 30 kg / cm ^a . Ethylene was then passed in until the pressure was increased by a further 10 kg / cm *. The polymerization reaction was carried out at 80 ^° C. for a period of 1 hour under constant pressure, with ethylene being introduced in order to maintain a total pressure of 40 kg / cm ¹ . As a result, 74.5 g became white

«Obtain powdered polyethylene. After this Polyethylene had been sufficiently dried, various methods were made by the methods described -physical properties of the polymer measured. The results obtained are in Table 8

»5 put together.

Table 8

Amount of

^H »
(kg / cm ¹ )

Total pressure
(kg / cm «)

Polymerisation

speed

(g EP / g cat hrs.)

10
20th
30th
40

355
320
341
298

Average molecular weight

235,000
171,000
124,000
100,000

35

Physical Properties dxrtssssix
results Melt index
Flow ratio
density 0.25
45
0.964
238 First yield strength

This result clearly shows that the known catalysts, a nitdrige Polymerisationsgeschwin- * o speed Doer in behaves-this at oer polymerization result clearly shows that the according dei invention (see. Example 9) polyolefins obtained aufweiser a <broader molecular weight distribution than those obtained by known methods.

Claims (8)

The presence of hydrogen is polymerized, claims: wooej jer pressure of the hydrogen is not greater than the pressure of the olefin to be polymerized. 1. Process for the polymerization of olefins
with the help of chromium oxide supported catalysts 5
at a temperature in the range between room temperature and 250 ⁰ C and a pressure in the loading ~ rich between normal pressure and 100 atmospheres in the presence of catalysts, characterized in that a cata- io. . _
lysator combination is used, which consists of As catalysts for the polymerization of olefins, a) on a heat-resistant metal oxide, especially of ethylene, are transition metals Chromium oxide and bonds known to be on a carrier such as SiIi- b) a pentaalkylsiloxyalane of the general ciumdioxid, aluminum oxide, silicon dioxide-aluminum formula . 15 nium oxide, zirconium oxide or thoroxide applied _ _{tri id} are. It is also known that when used K ₃ SiUAlK _{t of this catalog} for the polymerization reaction wherein the symbols R in each case for the same or the molecular weight of the polymer obtained various alkyl groups with 1 to 10 carbon atoms largely depend on the polymerization temperature atomic atoms stand, ao depends. Polymers that are suitable for consumers consists. suitable average molecular weight of 2. The method according to claim 1, characterized own to 100,000 overall about 50,000 are features in mind that a catalyst combination my is used at a polymerization temperature of 100, the component a) condition to 200 ⁰ C. was by a calcinieibare to chromium oxide a ₅ If the polymerization at a low tem-chromium compound on a heat-resistant metal temperature, for example, a temperature below 100 C, applied oxide and the application carried out in the presence of these catalysts see compound with a The temperature in the loading was, however, the polymerization rate ^! ch of 300 and 1200 ⁰ C was calcined, and speed reduced and a control of the molecular weight, whereby the atomic ratio between the silicon 30 weight and the polymer obtained was unim Intaalkylsiloxyalan and the chromium in possible, so that a technically usable polyethylene chromium oxide in the range of 0.01 to 500 based could not be obtained. Which is based on Si / Cr using. polymerization carried out by these catalysts 3. The method according to claims 1 and 2, there also has the disadvantage that the concentration diTch characterized in that a catalyst combination of the polyethylene was used in the polymerization system, the component a) of which must be trolled. If the polymerization was maintained by passing silicon dioxide and / or a temperature, as mentioned above, through silicon dioxide-aluminum oxide into an aqueous solution, the following is obtained: polyethylene is immersed in a solution of chromium trioxide, the impregnating solvent is dissolved. If the polymerisation of the metal oxide continued to dry and then proceed in a 40, the concentration of polyethylene oxygen gas atmosphere is increased at a temperature with the result that the viscosity of the poly between 500 and 100O ⁰ C by calcining merisationssystems rises. The increased viscosity was activated. causes the ethylene monomer to diffuse. on 4. The method according to claims 1 to 3, that this way the rate of polymerization characterized in that a catalyst component 45 is reduced. The polymerization reaction will therefore bination is used in which the atomic ratio is usually carried out so that a polyethylene ratio between silicon in the pentaalkylsiloxyalane concentration of less than 20% in a solution and the chromium in the chromium oxide is in the range of medium. 0.1 to 50 in terms of Si / Cr. A number of catalysts are also available. 5. The method according to claims 1 to 4, there has been beaten 50, which are produced by characterized in that the heat-resistant that said catalyst with an organometallic metal oxide Silicon dioxide is. see connection is combined to the mentioned 6. The method according to claims 1 to 5, there to improve catalysts so that they are a through characterized that the heat-resistant catalytic «activity, even at low tem-metal oxide have finely divided silica with a 55 temperature. Even with these improved Katasaverages Particle size less than an analyzer could, however, provide sufficient polymer Micron is. . sation rate at a low temperature 7. The method according to claims 1 to 6, da- are not achieved, and the molecular weights characterized in that ethylene, propylene could not be controlled. and / or butene-1 in an inert solvent 60 When researching into optionally in the presence of gaseous he '"position of catalysts, which a tech hydrogen is polymerized. nically satisfactory polymerization rate 8. The method according to claims 1 to 7, since not only at high, but also at lower characterized in that ethylene or a temperature and a free control of the low molecular weight of propylene-containing ethylene allow 65 weights, was now surprising in an inert solvent a tem- derweise found that a catalyst having a temperature between 60 and 15O ⁰ C at a pressure extremely high catalytic activity even at low from atmospheric pressure to 100 atmospheres in temperature, can be prepared by