NO750687L - - Google Patents

Description

Method for the production of

a catalyst.

In the polymerization of propylene or higher α-olefins with Ziegler catalysts, besides the technically particularly interesting highly crystalline polymers, which are insoluble or heavily soluble in the hydrocarbons used as dispersants under the polymerization conditions, amorphous, easily soluble polymers and oil are also obtained. According to Natta, the highly crystalline polymers are sterically ordered and are termed "isotactic", while the soluble polymers are sterically disordered and are termed "atactic".

The formation of isotactic or amorphous poly-α-olefins is controlled by the catalyst system. For an economically viable method, it is necessary to have selectively acting catalyst systems which exclusively resp. almost exclusively allows the desired polymers to occur.

A process is known (compare British Patent No. 895,595) according to which the selectivity of such catalysts can be considerably increased with regard to the formation of polymers with high isotactic amounts when subjecting the reaction product of TiCl^ and halogen-containing organoaluminum compounds to a thermal treatment by a temperature from 40 to 150°C and possibly after this treatment is washed out several times with an inert solvent. This washed, tempered catalyst is then activated by the olefin polymerization with fresh diethyl aluminum monochloride. The effect of these tempered catalysts can further be varied by the thermal treatment being carried out in the presence of complex formers or double salt formers such as ethers and sodium chloride.

The invention relates to a method for producing a catalyst by reacting titanium tetrachloride with an organoaluminum compound containing an aluminum dialkyl chloride in an inert hydrocarbon solvent, thermal treatment of the TiCl^-containing reaction product in the presence of an ether, separation and washing of the reaction product (component A) and mixing with an aluminum dialkyl halide (component B) and optionally with a cyclopolyene as stereoregulator (component C), the method being characterized in that for the production of component A, by reacting the titanium tetrachloride with the organoaluminum compound containing an aluminum dialkyl chloride, the organoaluminum compound is at a temperature from -20 to +20°C in a molar ratio between aluminum dialkyl chloride and titanium tetrachloride from 0.8:1 to 1.5:1 to the titanium tetrachloride, subjecting the formed TiCl^-containing solid reaction product to a thermal treatment at a temperature from ^0 to 150°C, carries out a further thermal treatment in the presence of dialkyl ether and separates the solid reaction product.

The invention further relates to the catalyst produced by this method and its use for the polymerization of α-olefins.

For the preparation according to the invention of the catalyst, titanium tetrachloride is first reacted in an inert hydrocarbon solvent with an aluminum dialkyl chloride-containing organic aluminum compound.

The organoaluminum compound containing an aluminum dialkyl chloride can either be an aluminum dialkyl chloride with alkyl groups of 1 to 6 carbon atoms, preferably aluminum diethyl chloride, -dipropyl chloride, -diisopropyl chloride, -diisobutyl chloride, above all aluminum diethyl chloride, or an aluminum alkyl sesquichloride, which is an equimolar mixture of aluminum dialkyl monochloride and aluminum alkyl dichloride, preferably aluminum ethyl sesquichloride, -propyl sesquichloride, -isopropyl sesquichloride or -isobutyl sesquichloride. Of the sesquichlorides, aluminum ethyl sesquichloride is particularly preferred.

In the reaction of titanium tetrachloride and the organoaluminum compound containing an aluminum dialkyl chloride, the molar ratio between aluminum dialkyl chloride and titanium tetrachloride is 0.8 : 1 to 1.5 : 1, preferably 0.9 : 1

to 1.1:1, the aluminum compound being added to the dissolved titanium tetrachloride. One works at a temperature of -20 to +20°C, preferably 0 to 5°C

As a solvent, an alkane or cycloalkane liquid at the prescribed reaction temperature is advantageously used, such as, for example, hexane, heptane, octane, cyclohexane or a hydrocarbon mixture, such as, for example, a petrol fraction with a boiling range of 130 to 170°C. Solvents, which are used as dispersants in the polymerization of α-olefins, are finally usable. The amount of solvent is preferably chosen so that the titanium tetrachloride is used in a 40 to 60% by weight solution, the organoaluminum compound in 15% to 25% by weight solution. The same solvent is also used for the following reactions.

The TiCl^-containing solid reaction product formed is separated from the hydrocarbon-soluble reaction products, washed with the solvent and subjected in suspension at a temperature from 40 to 150°C, preferably 90 to 110°C, with stirring to a first thermal treatment. This first thermal treatment can also be carried out before the separation of the hydrocarbon-soluble reaction products, i.e. in their presence. In this case, the washing of the TiCl-^-containing reaction product with inert hydrocarbon takes place after the first thermal treatment. This thermal treatment can also advantageously be carried out in several stages of different temperatures, for example in the first stage at 80 to 95°C and in the second stage at 100 to 110°C. The duration of the first thermal treatment depends on the temperature. It will last longer at a lower temperature and vice versa. 30 to 600 minutes is beneficial. The thermally treated and washed TiCl^-containing solid reaction product is suspended in an inert hydrocarbon and subjected to a further thermal treatment in the presence of a dialkyl ether and optionally a cyclopolyene.

If the solid reaction product was separated and washed out from the mother liquor, it is for this purpose suspended again in the solvent in such an amount that the titanium concentration amounts to 0.5 to 2.5 mol TiCl-^/liter, preferably 1.5 to

2.5 mol TiCl-j/liter solvent. This second thermal treatment is carried out at a temperature from 40 to 150°C,

preferably from 40 to 120°C, especially from 60 to 90°C. Suitable dialkyl ethers are those with 2 to 5 carbon atoms in them

each alkyl group, for example diethyl ether, di-n-propyl ether, di-isopropyl ether, di-n-butyl ether, diisobutyl ether, di-n-butyl ether is particularly suitable. The molar ratio between titanium trichloride and dialkyl ether during the thermal treatment is suitably 1:0.6 to 1:1.2, preferably 1:0.9 to 1:1.

Suitable cyclopolyenes include norcaradiene and cyclopolyenes with 7 ring members and 3 non-cumulative double bonds in the ring as well as those with 8 ring members and 3 or 4 non-cumulative double bonds in the ring. Cycloheptatriene-(1,3,5), cyclooctatriene-(1,3,5) and cyclooctatetraene-(1,3,5j7) and their alkyl- and alkoxy-substituted derivatives are preferably used, the alkyl group containing 1 to 4 carbon atoms, especially the cycloheptatriene -(1,3,5) itself. The molar ratio between titanium trichloride and cyclopolyene is 1:0.001 to 1:0.15, preferably 1:0.005 to 1:0.08, especially 1:0.05 to 1:0.1.

Thereby, either the solid suspension can first be presented and the dialkyl ether added, or the reverse can be done. In the second tempering, the dialkyl ether can be used dissolved in a solvent, however, it is more advantageous to use this undiluted. The addition of the dialkyl ether to the solid suspension or the addition of the solid suspension to the dialkyl ether can take place at a different tempering temperature within seconds to 5 hours, preferably from 1 to 30 minutes. Before adding the cyclopolyene, the suspension is preferably first treated for 1 to 45, preferably 5 to 30 minutes with the ether alone. After bringing together the reaction participants, the mixture is stirred for 5 to 300 minutes, preferably 30 to 60 minutes at this thermal treatment temperature.

After the second thermal treatment, the TiCl-^-containing reaction product is thoroughly washed out with a hydrocarbon solvent. The solid reaction product is then optionally treated in suspension with a concentration of titanium from 0.001 to 0.5 mol TiCl-^pr., liter, preferably 0.05 to 0.1 mol TiCljpr. liter of solvent with an aluminum alkyl halide. Aluminum alkyl halides of the formula AlRnXj_n, in which R means an alkyl residue with 2 to 8 carbon atoms, X means a halogen atom and n means a number from 1 to 2, preferably the aluminum dialkyl halides, -alkyl dihalides and -sesquihalides are suitable for this purpose. In particular, aluminum diethyl chloride, aluminum ethyl dichloride and aluminum ethyl sesquichloride are used. A very economical method consists in using for this post-treatment the mother liquor formed during the production of the reaction product containing TiCl, which in particular contains aluminum alkyl dichloride.

The molar ratio of aluminum alkyl halide to TiCl^

in the suspension to be treated amounts during the reaction to 0.8:1 to 10:1, preferably 1:1 to 5:1. The reaction is carried out at a temperature from 0 to 60°C, preferably at 20 to 40°C with stirring.

Advantageously, the post-treatment with the aluminum alkyl halide takes place in the presence of smaller amounts of a cyclopolyene. Suitable for this are norcaradiene and cyclopolyenes with 7 ring members and 3 non-cumulative double bonds in the ring as well as those with 8 ring members and 3 or 4 non-cumulative double bonds in the ring. Cycloheptatriene-(1,3,5), cyclooctatriene-(1,3,5) and cyclooctatetraene-(1,3,5,7) and their alkyl- and alkoxy-substituted derivatives are preferably used, the alkyl group containing 1 to 4 carbon atoms, especially cycloheptatriene-(1,3,5) itself.

The molar ratio of titanium trichloride to cyclopolyene is 1 : 0.001 to 1 : 1, preferably 1 : 0.005 to 1 : 0.8, especially 1 : 0.075 to 1 : 0.5.

If the post-treatment with an aluminum alkyl halide is resumed in the presence of a cyclopolyene, the possible addition of a third catalyst component (component C) during the polymerization can be partially or completely omitted.

Furthermore, the post-treatment with the aluminum alkyl halide can take place in the presence of a small amount of an olefin, a cyclopolyene - of the same type and in the same way as stated above - can be present or absent. Suitable are mono-olefins with 2 to 10 carbon atoms. Ethylene, propylene, butene-(1) or 4-methylpentene-(1) are preferably used. The molar ratio between titanium trichloride and olefin is 1:1 to 1:100, preferably 1:1 to 1:50, especially 1:1.5 to 1:20.

An aluminum alkyl dihalide or aluminum alkylsesquihalide, it is necessary to separate the formed catalyst component A from the suspension and to wash it out with an inert hydrocarbon solvent. When using an aluminum dialkylmonohalide, on the other hand, the separation and washing out of catalyst component A can be omitted. Moreover, in this case the amount of catalyst component B can be reduced by the amount of aluminum dialkyl monohalide used for the post-treatment.

Catalyst component A can, after separation from the solvent by decantation or filtration under the exclusion of air and moisture, be dried and then stored.

Catalyst component A according to the invention can be used either as a suspension, as it appears for example by post-treatment with an aluminum alkyl halide, or isolated, washed and suspended in an inert hydrocarbon solvent together with an aluminum dialkyl halide (component B) and optionally a cyclopolyene (component C) for the polymerization of α-olefins. These α-olefins are those with the formula CH2=CHR, in which R means an alkyl radical with 1 to 8 carbon atoms. Propylene, butene-(1), pentene-(1), 3-methylbutene-(1), 4-methylpentene-(1) and 3-methylpentene-(1) are preferably polymerized with the aid of the catalyst according to the invention, especially propylene. In addition to the homopolymerization, the catalyst according to the invention is also suitable for the polymerization of mixtures of these olefins with each other and/or with ethylene, the content of one of the ct-olefins in the mixture being at least 95% by weight and the content of ethylene a maximum of 5% by weight, each time referred to the total amount of monomer. Particularly noteworthy are mixtures of propylene with small amounts of ethylene, the ethylene content being 0.5 to 5, preferably 1.5 to 3, by weight. Furthermore, the catalyst according to the invention is suitable for block copolymerization of these α-olefins with each other and/or with ethylene, the content of ethylene being less than 25% by weight, preferably for the production of block copolymers of propylene and ethylene. These block copolymers are distinguished by a high hardness and an excellent impact strength at temperatures below 0°C.

The polymerization can be carried out continuously or discontinuously in suspension or in the gas phase at a pressure of 1 to 50 kg/cm 2 , preferably 1 to 40 kg/cm 2 .

The suspension polymerization is carried out in an inert solvent such as an olefin-poor petroleum fraction with a boiling range of 60 to 250°C which must be carefully freed from oxygen, sulfur compounds and moisture as well as saturated, aliphatic and cycloaliphatic hydrocarbons such as butane, pentane, hexane, heptane, cyclohexane , methylcyclohexane or aromatics such as benzene, toluene and xylene. The suspension polymerization can also preferably be carried out using the α-olefin to be polymerized, for example in liquid propylene as a dispersant.

A further method consists in the polymerization being carried out in the absence of a solvent in the gas phase, for example in a fluidized bed.

The molecular weight is regulated, if necessary, by adding hydrogen.

The quantity of a catalyst component A depends on the prescribed reaction conditions, in particular on pressure and temperature. 0.05 to 10 mmol TiCljpr is usually used. liter of solvent in the case of suspension polymerization or reactor volume in the case of gas phase polymerization, preferably 0.1 to 3 mmol TiCl^.

Catalyst component B has an aluminum dialkyl monochloride with the formula AlP^Cl, in which R is an aliphatic hydrocarbon residue with up to 8 carbon atoms, preferably aluminum diethyl monochloride. The amount of component B is chosen so that the molar ratio between component B and component A (referred to TiClj) is 0.5:1 to 100:1', preferably 1 1 to 10:1.

With this catalyst consisting of the components

A and B, a high polymerization activity is already achieved with a good stereospecificity. However, the stereospecificity is strongly dependent on the polymerization temperature. Thus, for example, at a polymerization temperature of 60°C, when polymerizing propylene in the dispersant, soluble amounts of less than 3.0% by weight (referred to the total polymer), preferably less than 2.0% by weight, are obtained. If the polymerization temperature is increased to 70 to 80°C, the unwanted soluble amounts increase up to 4% by weight. On the other hand, a higher polymerization temperature is desirable with regard to the removal of polymerization heat.

Furthermore, it is also known that increasing pressure and thus a higher polymerization rate increases the soluble amounts. Thus, a polymerisation of propylene in liquid propylene (around 32 kg/cm 2 , 70 C) yields up to * 6% of soluble amounts.

The inherently good stereospecificity of the catalyst can be further increased at higher pressure and higher temperature during the polymerization, using a cyclopolyene as catalyst component C. Cyclopolyenes of the same type as stated above are suitable. The addition of component C to component A conveniently takes place together with component C at the beginning of the polymerization. The molar ratio between component C and component A (calculated as TiCl-^) is 0.1:1 to 1:1, preferably 0.2:1 to 0.6:1.

The polymerization in the presence of the catalyst according to the invention is carried out at a temperature from 20 to 120°C, preferably 50 to 90°C. A higher temperature is indeed possible in principle, but the amount of soluble atactic polymer will be greater.'

In the multi-stage thermal treatment according to the invention, titanium trichloride-containing reduced solids, as the last stage of the thermal treatment is carried out in the presence of a dialkyl ether and a cyclopolyene, a catalyst (component A) is obtained, which already in combination with an aluminum dialkyl halide as an activator (component B) in the polymerization of α-olefins leads to a significant increase in the turnover rate with improved stereospecificity. In relation to the state of the art which is known from British patent no. 895,595, at the same polymerization temperature and the same pressure, one finds around over 100% greater activity with the same good stereospecificity. With the higher catalyst activity (g polymer/g catalyst), a smaller amount of catalyst can be used for the polymerization to produce a corresponding space-time yield, whereby the laborious work-up is significantly facilitated or the same work-up leads to a better removal of the catalyst. In the case of polymerization under increased pressure, for example over 20 kg/cm , which is either carried out in gas phase or in liquid α-olefin, for example liquid propylene, the yields are so large that a catalyst removal can be completely disregarded (yield over 100 g polymer per 1 mmol TiCl^).

Example 1 to 3-

A. Catalyst preparation.

Eel. Reduction of TiCl^ by means of aluminum ethyl sesquichloride.

1090 ml of a hydrogenated, oxygen-free petrol fraction (boiling point 140 to 165°C) and 550 ml of titanium tetrachloride (5 mol) are placed in a 10-litre mixing vessel, excluding air and moisture, and at 0°C are added dropwise over the course of 8 hours with stirring ( 250 revolutions per minute) and nitrogen overlay a solution of 1111.2 g of aluminum ethyl sesquichloride (containing 4.5 mol of aluminum diethyl monochloride) in 3334 g of the gasoline fraction. A reddish-brown fine precipitate separates. The mixture is then stirred for 2 hours at 0°C and then 12 hours at room temperature.

The suspension is then heated for 4 hours at 90°C

and then a further 6 hours at 110°C. The separated precipitate is separated after settling from the overlying mother liquor by decantation and washed five times with 2000 ml of the petrol fraction each time. The washed solid reaction product is resuspended in Ben's infraction and the suspension is adjusted to a concentration of 2 mol TiCl^/litre. Determination of the suspension's content of trivalent titanium takes place by titration with a Ce(IV) solution.

A. 2. Other thermal treatment in the presence of di-n-butyl ether.

In a 2 liter mixing vessel, while excluding air and moisture under nitrogen overlay, 500 ml of a 2-molar suspension (corresponding to 1 mol TiCl^) is heated at 85°C and then added dropwise at this temperature while stirring during 30 minutes l6l ml di-n -butyl ether (equivalent to 0.95 mol). The suspension is then held for 1 hour at 85°C. When the ether is added, the mother liquor is colored olive green. Catalyst component A is then washed five times with 500 ml of the petrol fraction each time.

B. Polymerization of propylene.

In a 1-litre glass autoclave, while excluding air and moisture, 0.5 liters of the above-mentioned hydrogenated petrol fraction (boiling point 140 to 165°C) are taken and saturated at 55°C with propylene. The amount specified in table 1 is then added

A1(C2H^)2C1 (activator (component B)) and then component

A (example 1 and • 2) resp. thermally treated solid reaction product according to A.l (example 3 = comparison test A) corresponding each time to 1 mmol TiCl-,. Then 0.25 kg per cm 2 of hydrogen - and within 5 minutes so much propylene is impressed that a pressure of 6 kg/cm^ builds up. This pressure is maintained during the polymerization duration by post-pressing of propylene. After a polymerization duration of 2 hours, the autoclave is de-energized and the polymer suspension is sucked off over a filter, the polymer is washed on the filter with 1 liter of hot solvent (70°C) and dried in a vacuum at 70°C.

To determine the soluble amount (atactic polypropylene) formed during the polymerization, the mother liquor and the polymer suspension and the washing solutions are combined and evaporated to dryness in a vacuum. The polymerization results are listed in Table 1.

Example A (comparison experiment B).

A. Catalyst preparation.

The reduction of TiCl2 by means of aluminum ethyl sesquichloride is carried out as indicated in example 1 A.l, the precipitate after the reaction is not subjected to any thermal treatment, but is simply washed out, suspended and the suspension adjusted to a concentration of 2 mol TiCl1/litre. 500 ml of this 2 molar suspension (corresponding to 1 mol of TiCl-^) is heated to 85°C. At this temperature, 161 ml of di-n-butyl ether (equivalent to 0.95 mol) is added dropwise with stirring over the course of 30 minutes. The suspension is then held for 1 hour at 85°C. When the ether is added, the mother liquor turns olive green.

The solid reaction product is washed five times with 1000 ml of the petrol fraction each time.

B. Polymerization of propylene under pressure.

The polymerization is carried out with the indicated catalyst component A, as indicated in example 1 B. The result is listed in table 1.

Example 5.

Polymerization of propylene in liquid monomer.

A 16-litre enamel vessel, equipped with stirrers, mantle heating and gas inlet pipe, is flushed at room temperature with pure nitrogen and then with propylene. A pressure of 0.5 kg/cm 2 hydrogen is then built up and a solution of 32 mmol Al (CjH ^) .-.Cl in 6 liters liquid

propylene and a suspension consisting of the catalyst component A prepared according to example 1 A (4 mmol TiCl-^) and 6 liters of liquid propylene. The vessel is then heated to 70°C, the pressure thereby rising to approx. 32 kg/cm 2. When cooling, the internal temperature is kept at 70°C. The polymerization starts after a few minutes. The experiment is interrupted after 6 hours when the vessel is relaxed. After drying, 5.5 kg of a good flowable polymer with a volume weight of 520 g/litre is obtained. The tub's RSV value is 2.6. After 16 hours of extraction with heptane, a soluble amount of 6.5 wt# is found. The bullet pressure hardness is 670 kp/cm<2> (DIN 53 456).

Example 6.

Polymerization of 4-methylpentene-(1).

In a 2 liter mixing vessel equipped with a thermometer and gas inlet tube, while excluding air and moisture, 1 liter of a hydrogenated, oxygen-free petrol fraction (boiling point 140 to 165°C) is taken and flushed with pure nitrogen. Then, at 50°C, 8 mmol of aluminum diethyl monochloride (= 0.97 ml) and of the catalyst component A produced according to example 1 A corresponding to 5 mmol of TiClj are added. 200 g of 4-methylpentene-(1) are then added dropwise over the course of 3 hours. The polymerization temperature is kept at 55°C. The polymerization starts after a few minutes. The polymer separates as a fine precipitate. After completion of the addition, the mixture is stirred for a further 2 hours at 55°C. The polymerization is then interrupted by the addition of 50 ml of isopropanol and stirred for 1 hour at 60°C, the mixture is extracted with hot water and then sucked off hot. After thorough washing with hot solvent (gasoline) and acetone and drying in vacuum at 70°C, 190 g of colorless poly-4-methylpentene-(1) are obtained. The polymer has a volumetric weight of 520 g/l. In the mother liquor, there is a very small soluble amount of 0.3%.

Examples 7 to 12.

A. Catalyst component A is prepared according to example 1 A.

B. Polymerization of propylene.

In a 1 liter glass autoclave, while excluding air and moisture, 0.5 liters of a hydrogenated petrol fraction (boiling point 140 to 165°C) are taken and saturated at 55°C with propylene. After that, the amounts of AlCCgH^^Cl (activator, component B) newly distilled cycloheptatriene-(1,3,5) given in table 2 are introduced

(component C) and then the above-mentioned catalyst component A (each time 1 mmol TiCl^). Then 0.25 kg/cm hydrogen is impressed and in the course of 5 minutes so much propylene is impressed that a pressure of 6 kg/cm is built up. This pressure is maintained during the polymerization duration by post-pressing of propylene. After a polymerization duration of 2 hours, the autoclave is released and the polymer suspension is sucked off over a filter. The polymer is washed on the filter with 1 liter of hot solvent (70°C) and dried in vacuum at 70°C.

At polymerization temperatures greater than 60°C

(see table 2) is first polymerised for 10 minutes at 60°C and then the higher polymerisation temperature is first set.

Example 13.

Polymerization of propylene with liquid monomer.

A 16 liter enamel vessel equipped with stirrer, jacket heating and gas introduction tube is flushed at room temperature with pure nitrogen and then with propylene. A pressure of 0.5 kg/cm 2 hydrogen is then built up and a solution of 32 mmol AltC^H^^Cl in 6 liters of liquid propylene and a suspension, consisting of the catalyst component A prepared according to example 1 A (4 mmol TiCl-^) as well as 1.6 ml of a 1-molar solution of cycloheptatriene-(1,3,5) (component C) in hexane (1.6 mmol) and finally 6 liters of liquid propylene. It is then heated to 70°C, the pressure thereby increases to approx. 32 kg/cm 2. When cooling, the internal temperature is kept at 70°C. The polymerization starts after a few minutes. The trial is stopped after 6 hours, when the vessel is relaxed. After drying, 5.8 kg of a good flowable polymer with a volume weight of 550 g/l are obtained. The RSV value is 2.7. After 16 hours of extraction with heptane, a soluble quantity of 2.8 weight SK is found. Ball pressure hardness is 820 kp/cm<2> (DIN 53 456).

If the polymerization is carried out analogously with a catalyst, which does not contain component C, a soluble amount of 6.5% by weight is found in the polypropylene (compare example 5).

Example 14.

A. Catalyst preparation.

Eel. Reduction of TiCl^ by means of aluminum ethyl sesquichloride.

1090 ml of a hydrogenated, oxygen-free petrol fraction (boiling point 140 to 165°C) and 550 ml of titanium tetrachloride (5 mol) are placed in a 10 liter mixing vessel, excluding air and moisture, and at 0°C are added dropwise over the course of 8 hours under stirring (250 revolutions per minute) and nitrogen overlay a solution of 1111.2 g of aluminum ethyl sesquichloride (containing 4.5 mol of aluminum diethyl monochloride) in 3334 g of the gasoline fraction. A reddish-brown fine precipitate separates. The mixture is then stirred for 2 hours at 0°C and then 12 hours at room temperature.

The suspension is then heated for 4 hours at 90°C and then a further 6 hours at 110°C. After settling, the separated precipitate is separated from the overlying mother liquor by decantation and washed five times with 2000 ml of the petrol fraction each time. The washed solid reaction product is suspended again in the petrol fraction and the suspension is adjusted to a concentration of 2 mol TiCl-^/litre. The determination of the suspension's content of trivalent titanium takes place by titration with a Ce-(IV) solution.

A.2. Other thermal treatment in the presence of di-n-butyl ether.

In a 2 liter mixing vessel, while excluding air and moisture under a nitrogen blanket, 500 ml of the 2-molar suspension (corresponding to 1 mol TiCl-^) is heated to 80°C and then added dropwise at this temperature while stirring over the course of 30 minutes l6l ml di -n-butyl ether (equivalent to 0.95 mol). The suspension is then held for one hour at 80°C. When the ether is added, the mother liquor is colored olive green. The solid TiCl^-containing reaction product is then washed five times, each time with 500 ml of the petrol fraction.

A.3. Finishing with aluminum diethyl monochloride.

In 100 ml of the petrol fraction, while excluding air and moisture, 1 mmol (TiCl^) of the TiCl^-containing reaction product A prepared according to A.1 and A.2 and 2 mmol aluminum diety Imonochloride are added and then stirred for one hour at room temperature.

B. Polymerization of propylene.

0.4 liters of a hydrogenated, oxygen-free petrol fraction (boiling point 140 to 165°C) are placed in a 1-litre glass autoclave while excluding air and moisture and saturated at 55°C with propylene. 2 mmol of aluminum diethyl monochloride are then added to the activator (component B) 7 and 0.2 mmol of cycloheptatriene-(1,3,5)

(component C) and then the one according to A.3. post-treated TiCl^ suspension (1 mmol). Next, so much hydrogen is introduced that a pressure of 0.25 kg/cm 2 is achieved and then so much propylene is introduced in the course of 5 minutes that a total pressure of 6 kg/cm p is built up. This pressure is maintained during the polymerization duration by introducing propylene. • After a polymerization duration of 2 hours, the autoclave is released and the polymer suspension is sucked off over a filter, the filter cake is washed on the filter with 1 liter of hot solvent (70°C) and dried in a vacuum at 70°C. 248 g of insoluble polypropylene is obtained in the dispersant. The volume weight of the well-flowable polymer powder is 560 g/litre, the RSV value 2.6 dl/g and the bullet pressure hardness 840 kp/cm<2> (DIN 53456). To determine the soluble amount formed during the polymerization (atactic polypropylene), the polymerization mother liquor and the washing solutions are combined and evaporated to dryness in a vacuum. There are 1.4 g of soluble polypropylene (= 0.57% referred to total polymer).

Example 15.

A. Post-treatment of the TiCl-^-containing reaction product with Al(C2Hj-)2Cl and cycloheptatriene-(1,3,5) •

To 100 ml of the petrol fraction, while excluding air and moisture, 1 mmol (TiCl-^) of that according to example 14 A.l. to A.2 prepared TiCl^-containing reaction product and 2 mmol aluminum diethyl monochloride and 0.2 mmol cycloheptatriene-(1,3,5) and then stirred for one hour at room temperature.

B. Polymerization of propylene.

The polymerization is carried out under the same conditions as stated in example 14, however without further addition of cycloheptatriene-(1,3>5)• 230 g in dispersant undissolved polypropylene are obtained (volumetric weight 553 g/litre, RSV value 2.2 dl/g, bullet pressure hardness 850 kp/cm<2> (DIN 53456), .atactic amount in the mother liquor 0.5% referred to total polymer). Example 16.

A. Post-treatment of the TiCl^-containing reaction product with A1(C2H5)2C1 and cyclooctatetraene-(1,3,5j7)•

The post-treatment is carried out as in example 15, however, cycloheptatriene-(1,3,5)cyclooctatetraene-(1,3,5,7) is used instead. In 100 ml of the gasoline fraction, with the exclusion of air and moisture, 1 mmol (TiCl^) of the olive-green suspension (Example 14 A.2.) 0.2 mmol cyclooctatetraene-(1,3,5,7) and 2 mmol aluminum diethyl monochloride and then the mixture is stirred for one hour at room temperature.

B. Polymerization of propylene.

The polymerization of propylene is carried out under the conditions specified in example 14. 252 g of undissolved polypropylene with a volume weight of

540 g/litre and an RSV value of 2.1 dl/g (ball pressure hardness 830 kp/cm<p>) (DIN 53456). The amount of dissolved polypropylene amounts to 1.2 g (= 0.47% referred to total polymer).

Example 17.

The preparation of the TiCl^-containing reaction product takes place as indicated in example 14 under A.l. and A.2.. The post-treatment of the TiCl^-containing reaction product (A.2.) with aluminum diethyl monochloride and cycloheptatriene-(1,3 s5) is carried out in the presence of an olefin as follows: 100 mmol of the one according to example 14 A.2 . prepared TiCl-^-suspension j on is diluted by adding approx. 800 ml of the petrol fraction to 0.1 mol TiCl^pr. liter of dispersant and, excluding air and moisture, add 500 mmol A1(C2H5)2C1 (= 62.92 ml) and 40 mmol cycloheptatriene-(1.3j5) (= 4.16 ml) and stir for 5 minutes at room temperature. Then, at room temperature (cooling), 300 mmol (= 12.6 g) of propylene are introduced over the course of one hour in gaseous form (6.7 1 C^Hg). To avoid the formation of a vacuum, the propylene is diluted with a small amount of argon. The TiCl 2 -containing catalyst suspension is then stirred for one hour at room temperature under argon. Determination of the content of trivalent titanium (as TiCl^) takes place by titration with a Ce(IV) solution.

In a 1 liter glass autoclave, while excluding air and moisture, 0.5 liters of a hydrated, oxygen-free bone sin fraction (boiling point 140 to 165°C) are taken and saturated at 70°C with propylene. 1 mmol of the above-mentioned suspension (10.9 ml) is then added. Next, so much hydrogen is introduced that a pressure of 0.25 kp/cm 2 is achieved and then, in the course of 5 minutes, so much propylene is introduced that a total pressure of 6 kp/cm is built up. This pressure is maintained during the polymerization duration by introducing propylene. At the same time, the temperature is increased to 80°C and kept at this temperature during cooling. After a polymerization duration of 2 hours, the autoclave is de-energized. The further processing takes place as indicated in example 1 B. - 230 g of polypropylene insoluble in the dispersant are obtained in the form of a translucent grain. The RSV value is 2.2 dl/g and the volumetric weight 542 g/litre and the bullet pressure hardness 860 kp/cm 2 (DIN 53456). The mother liquor contains 5 g of soluble (atactic) polypropylene (= 2.1% by weight referred to total polymer).

Example 18.

Polymerization of propylene in liquid monomer.

A 16 liter enamel vessel equipped with stirrers, jacket heating and gas introduction pipe is flushed at room temperature with pure nitrogen and then with propylene. Then, by introducing hydrogen, a pressure of 0.5 kg/cm 2 is built up and through a sluice, a solution of 20 mmol of A1(C2H^)2C1 in 6 liters of liquid propylene is added and then through a further sluice, 4 mmol (referred to TiCl^ ) of the suspension of component A prepared according to example 17, which contains 20 mmol Al (C2Hj-) 2C1, 1.6 mmol cycloheptatriene- (1, 33 5 ) and a small amount of polypropylene, diluted with 6 liters of liquid propylene. It is then heated to 70°C, the pressure thereby increases to 32 kg/cm<2>. During cooling, the internal temperature is kept at 70°C. The polymerization starts after a few minutes. The experiment is interrupted after 3 hours when the vessel is relaxed. After drying, 4 kg of a good flowable polymer with a volume weight of 545 g/litre is obtained. The polymer grain is translucent. The RSV value is 1.9 dl/g. After 16 hours of extraction with heptane, a soluble amount of 2.8% by weight is found. The ball compressive hardness is 780 kp/cm<2> (DIN 53456).

Example 19.

5 mmol (TiClj) of that according to example 14 A.l. to

A. 2. prepared TiCl^-containing reaction product is suspended

in 500 ml of the petrol fraction under the exclusion of air and moisture and then 10 mmol of aluminum diethyl monochloride and 1 mmol of cycloheptatriene-(1.335) are added > then the mixture is stirred for one hour at room temperature.

In a 2 liter mixing vessel, equipped with a thermometer

and gas inlet pipe, fill with 1 liter of a hydrogenated, oxygen-free petrol fraction (boiling point 140 to 165°C) and flush with pure nitrogen. The above-mentioned suspension of component A is then added at a temperature of 50°C and 200 g of 4-methylpentene-(1) is added dropwise over the course of 3 hours. The polymerization temperature is kept at 55°C. The polymerization starts after a few minutes. The polymer separates as a fine precipitate.

After completion of the additions, the mixture is stirred for a further 2 hours at 55°C. The polymerization is then interrupted by the addition of 50 ml of isopropanol, the mixture is stirred for one hour at 60°C, extracted with hot water and then sucked off hot. After thorough washing with hot solvent (petrol) and acetone and drying in vacuum at 70°C, 194 g of colorless poly-4-methylpentene-(1) are obtained. The polymer has a volume weight of

515 g/litre. There is one in the mother liquor. very small soluble amount of 0.6% by weight.

Example 20.

A. Catalyst preparation.

Eel. Reduction of TiCl^ by means of aluminum ethyl sesquichloride,

In a 10 liter mixing vessel under the exclusion of air and moisture 1090 ml of a hydrogenated, oxygen-free gasoline fraction (boiling point 140 to 165°C) and 550 ml of titanium tetrachloride (5 mol)

and at 0°C, a solution of 1111.2 g of aluminum ethyl sesquichloride (containing 4.5 mol of aluminum diethyl monochloride) in 3334 g of the petrol fraction is added dropwise during 8 hours with stirring (250 revolutions per minute) and nitrogen overlay. A reddish-brown fine precipitate separates. The mixture is then stirred for 2 hours at 0°C and then 12 hours at room temperature.

The suspension is then heated for 4 hours at 90°C and then for a further 6 hours at 110°C. The formed precipitate is separated after settling from the overlying mother liquor by decantation and washed five times with each time 2000 ml of the petrol fraction. The washed solid reaction product is suspended again in the petrol fraction and the suspension is adjusted to a concentration of 2 mol.TiCl^/litre. Determination of the suspension's content of trivalent titanium took place by titration with a Ce-(IV) solution.

A.2. Other thermal treatment in the presence of di-n-butyl ether

and cycloheptatriene-(1,3 >5)•

In a 2-liter mixing vessel, while excluding air and moisture under nitrogen overlay, 500 ml of the 2-molar suspension (corresponding to 1 mol TiCl^) is heated at 80°C and then added dropwise at this temperature while stirring over the course of 30 minutes 16l ml of di- n-butyl ether (equivalent to 0.95 mol). The suspension is then held for 30 minutes at 80°C and then 75 mmol of cycloheptatriene-(1,3,5) are added at this temperature

(= 738 ml) and stirred for a further 4 hours at 80°C. When the ether is added, the mother liquor turns olive green. The solid TiCl^-containing reaction product is then washed five times, each time with 500 ml of the petrol fraction.

A. 3. Finishing with aluminum diethyl monochloride.

In 100 ml of the petrol fraction, under exclusion of air and moisture, 1 mmol (TiCl^) of it according to A.l.

and A.2. prepared TiCl^-containing reaction product and 2 mmol of aluminum diethyl monochloride and is then stirred for one hour at room temperature.

B. Polymerization of propylene.

0.4 liters of a hydrogenated, oxygen-free petrol fraction (boiling point 140 to 165°C) are placed in a 1 liter glass autoclave while excluding air and moisture and saturated at 55°C with propylene. 2 mmol aluminum diethyl monochloride 7 activator (component B_)/ and 0.2 mmol cycloheptatriene-(1, 3, 5 ) are then added

(component C) and then it is introduced according to A.3. post-treated TiCl suspension (1 mmol). Next, so much hydrogen is introduced that a pressure of 0.25 kg/cm is achieved and then so much propylene is introduced within 5 minutes that a total pressure of 6 kg/cm is built up. This pressure is maintained during the polymerization duration by introducing propylene. After a polymerization duration of 2 hours, the autoclave is de-energized and the polymer suspension is sucked off over a filter, the filter cake is washed on the filter with 1 liter of hot solvent (70°C) and dried in a vacuum at 70°C. 228 g are obtained in dispersion

the agent insoluble polypropylene. The volume weight of the well-flowable polymer powder is 5^5 g/litre, the RSV value 2.1 dl/g and the bullet pressure hardness 850 kp/cm<2> (DIN '53^56). To determine the soluble amount (atactic polypropylene) formed during the polymerization, the polymerization mother liquor and the washing solution are combined and evaporated in vacuum to dryness. There are 1.2 g of soluble polypropylene (= 0.52% referred to total polymer).

Example 21.

A. Post-treatment of the TiCl^-containing reaction product with Al(C2Hp.)2Cl and cycloheptatriene-(1,3 3 5 ) •

To 100 ml of the gasoline fraction, while excluding air and moisture, 1 mmol (TiCl^) of the according to example 20 A.l. to A.2. prepared TiCl2-containing reaction product, 2 mmol aluminum diethyl monochloride and 0.2 mmol cycloheptatriene-(1.3j5) and then stirred for one hour at room temperature.

B. Polymerization of propylene.

The polymerization was carried out under the same conditions as stated in example 20, however without the addition of cycloheptatriene-(1,3,5). 228 g are obtained in the dispersing agent insoluble polypropylene (weight by volume 5^3 g/litre, RSV value 2 dl/g, bullet pressure hardness ■855 kp/cm<2> (DIN 53^56), atactic amount in the mother liquor 0.55% referred to aggregated polymer). Example 22.

A. Post-treatment of the TiCl^-containing reaction product with A1(C2H5)2C1 and cyclooctatetraene-(1,3,5,7).

The post-treatment is carried out as in example 21, however, instead of cycloheptatriene-(1,3,5)cyclooctatetraene-(1,3j5j7)• In 100 ml of the petrol fraction, while excluding air and moisture, 1 mmol'(TiCl^) of the olive-green suspension is added (example 20 A.2.), 0.2 mmol of cyclooctatetraene-(1,3,5,7) and 2 mmol of aluminum diethyl monochloride and then the mixture is stirred for 1 hour at room temperature.

B. Polymerization of propylene.

The polymerization is carried out under the conditions stated in example 20, however, without the addition of cycloheptatriene-(1,3j5) (component C). 260 g of insoluble polypropylene with a volume weight of 538 g/l is obtained in the dispersant

and an RSV value of 1.1 dl/g. (Ball pressure hardness 840 kp/cm<2>)

(DIN 53456). The amount of soluble polypropylene amounts to 1.5 g (= 0.57% referred to total polymer).

Example 23.

Preparation of the TiCl^-containing reaction product took place as indicated in Example 20 under A.l. and A.2. The post-treatment of the TiCl 2 -containing reaction product (A.2.) with aluminum diethyl monochloride and cycloheptatriene-(1,3,5) is carried out in the presence of an olefin in the following way: 100 mmol of that according to example 20 A.2. prepared TiCl^ suspension is diluted by adding approx. 800 ml of the petrol fraction to 0.1 mol TiCl^ per liters of dispersant and to the exclusion of

air and moisture add 500 mmol A1(C2H5)2C1 (= 62.92 ml)

and 40 mmol cycloheptatriene-(1,3,5) (= 4.16 ml) and stirred for 5 minutes at room temperature. Then, at room temperature (cooling), 300 mmol (= 12.6 g) of propylene are introduced over the course of one hour in gaseous form (6.7 liters of C^Hg). To avoid the formation of a vacuum, the propylene is diluted with a small amount of argon. The TiCl3-containing catalyst suspension is then stirred

hour at room temperature under argon. Determination of the content of trivalent titanium (as TiCl^) took place by titration with a Ce(IV) solution.

0.5 liters of a hydrogenated, oxygen-free petrol fraction (boiling point 140 to 165°C) are placed in a 1 liter glass autoclave while excluding air and moisture and saturated at 70°C

with propylene. 1 mmol of the above-mentioned suspension (= 10.9 ml) is then added. Next, so much hydrogen is introduced that a pressure of 0.25 kp/cm 2 is achieved and then so much propylene is introduced within 5 minutes that a total pressure of 6 kp/cm is built up. This pressure is maintained during the polymerization duration•by introducing propylene. At the same time, the temperature is increased to 80°C and kept at this temperature during cooling. After a polymerization duration of 2 hours, the autoclave is de-energized. The further processing takes place as indicated in example 1 B. 225 g of polypropylene insoluble in the dispersant is obtained

in the form of a translucent grain. The RSV value is 2.5 dl/g and the volume weight 548 g/litre and the bullet pressure hardness 830 kp/cm<p>(DIN 53456). In the mother liquor there are 4.5 g of soluble (atactic) polypropylene (= 1.96% by weight referred to total polymer).

Example 24.

Polymerization of propylene in liquid monomer.

A 16-litre enamel vessel, equipped with stirrers, jacket heating and gas inlet pipe, is flushed at room temperature with nitrogen and then with propylene. A pressure of 0.5 kg/cm<2> is then built up by introducing hydrogen

and through a sluice, a solution of 20 mmol Al (C^H,-) 2C1 in .6 liters of liquid propylene is added and then through a further sluice 4 mmol (referred to TiCl-^) of the suspension of component A prepared according to example 23 , which contains 20 mmol of Al (C^Hc-) 2C1, 1.6 mmol of cycloheptatriene- (1, 3, 5 ) and a small amount of polypropylene, diluted with 6 liters of liquid propylene. It is then heated to 70°C, the pressure thereby increases to 32 kg/cm 2. During cooling, the internal temperature is kept at 70°C. The polymerization starts after a few minutes. The experiment is interrupted after 3 hours when the vessel is relaxed. After drying, 338 kg of a good flowable polymer with a volume weight of 545 g/litre is obtained. The polymer grain is translucent. The RSV value is 2.2 dl/g. After 16 hours of extraction with heptane, a soluble amount of 3% by weight is found. The bullet pressure hardness is 760 kp/cm<2> (DIN 53456).

Example 25.

5 mmol (TiCl-j) of the according to example 20 A.l.

to A.2. produced TiCl^-containing reaction product is suspended in 500 ml of the petrol fraction while excluding air and moisture and then 10 mmol of aluminum diethyl monochloride and 1 mmol of cycloheptatriene-(1.3j5) are added and the mixture is then stirred for one hour at room temperature.

In a 2-litre stirring vessel, equipped with a thermometer and gas inlet tube, 1 liter of a hydrogenated, oxygen-free petrol fraction (boiling point 140 to 165°C) is taken and flushed with pure nitrogen. The above-mentioned suspension of component A is then added at a temperature of 50°C and 200 g of 4-methylpentene-(1) is added dropwise over the course of 3 hours. The polymerization temperature is kept at 55°C. The polymerization starts after a few minutes. The polymer separates as a fine precipitate. After the end of the addition, the mixture is stirred for another 2 hours at 55°C. The polymerization is then interrupted by the addition of 50 ml of isopropanol. The mixture is stirred for 1 hour at 60°C, extracted with hot water and then sucked off hot. After thorough washing out with hot solvent (petrol) and with acetone and drying in vacuum at 70°C, 190 g of colorless poly-4-methylpentene-(1) are obtained. The polymer has a volumetric weight of 505 g/litre. In the mother liquor there is the very small soluble amount of 0.7 wt?.

Claims (8)

1. Process for producing a catalyst by reacting titanium tetrachloride with an organoaluminum compound containing an aluminum dialkyl chloride in a inert hydrocarbon solvent, thermal treatment of the TiCl-j-containing reaction product, optionally in the presence of an ether, separation and washing of the reaction product (component A) and mixing with an aluminum dialkyl halide (component B) and optionally with a cyclopolyene as stereoregulator (component G), characterized in that for production of component A by the reaction of the titanium tetrachloride with the organoaluminum compound containing an aluminum dialkyl chloride has the organoaluminum compound at a temperature from -20 to +20°C in a molar ratio between aluminum dialkyl chloride and titanium tetrachloride of 0.8 : 1 to 1.5 : 1 to the titanium tetrachloride, subject the formed TiCl^ -containing solid reaction product to a thermal treatment by a temperature from 40 to 150°C, carries out a further thermal treatment in the presence of a dialkyl ether and separates the solid reaction product. 2. Method according to claim 1, characterized by . that the thermal treatment is carried out in the presence of a dialkyl ether, in the additional presence of a cyclopolyene. 3. Method according to claim 1 or 2, characterized in that the solid reaction product is subjected to a post-treatment with an aluminum alkyl halide, possibly a small amount of a cyclopolyene and/or an olefin being present. 4. Catalyst, produced by the method according to claim 1, 2 or 3. 5. Use of the catalyst, produced by the method' according to claim 1, 2 or 3 for the polymerization of α-olefins. 6. Process for producing a polyolefin by polymerizing at least one α-olefin with the formula CH2 =CHR, in which R means an alkyl residue with 1 to 8 carbon atoms or copolymerizing at least one such α-olefin with ethylene at a temperature from 20 to 120 °C and a pressure from 1 to 50 kg/cm 2 in the presence of a catalyst consisting of reaction products between titanium tetrachloride and an organoaluminum compound containing an aluminum dialkyl chloride in an inert hydrocarbon solvent, thermal treatment of the Ti Cl--containing reaction product, optionally in the presence of an ether, separation and washing of the reaction product (component A), an aluminum dialkyl halide (component B) and optionally a cyclopolyene as a stereoregulator (component C), characterized in that the polymerization is carried out in the presence of a catalyst, whose component A was prepared so that by reacting the titanium tetrachloride with the organoaluminum compound containing an aluminum dialkyl chloride, d an organoaluminum compound at a, temperature from -20 to +20°C in a molar ratio between aluminum dichloride and titanium tetrachloride of 0.8 : 1 to 1.5 : 1 to the titanium tetrachloride, the TiCl^ -containing reaction product was subjected to a thermal treatment at a temperature of 40 to 150°C, a further thermal treatment was carried out in the presence of a dialkyl ether and the solid reaction product was separated. . 7. Method according to claim 6, characterized in that the polymerization is carried out in the presence of a catalyst, whose component A was prepared such that the thermal treatment was carried out in the presence of a dialkyl ether in the additional presence of a cyclopolyene. 8. Method according to claim 6 or 7, characterized in that the polymerization is carried out in the presence of a catalyst, whose component A was prepared in such a way that the solid reaction product was subjected to a post-treatment with an aluminum alkyl halide, possibly a small amount of a cyclopolyene and/or an olefin was present.