NO750686L - - Google Patents

Description

Method for producing 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, also amorphous, easily soluble polymers and oils. According to Natta, the highly crystalline polymers are sterically ordered and termed "isotactic", while the soluble polymers are sterically disordered and termed "atactic".

The formation of isotactic or amorphous poly-α-olefins is controlled by the catalyst system. For an economically viable process, selectively acting catalyst systems are required, which exclusively or almost exclusively allow the desired polymers to occur.

A process is known (compare British patent no. 895,595) according to which the selectivity of such catalysts with regard to the formation of polymers with isotactic amounts is significantly increased, when subjecting the reaction product of TiCl^ and the halogen-containing organoaluminum compounds to a thermal treatment at a temperature from 40 to 150°C and possibly after this treatment wash 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.

Catalytic complexes are also mentioned, which are very active and stereospecific in the polymerization of α-olefins (compare DOS 2,213,086). These complexes are formed by reduction of titanium tetrachloride with an organoaluminum compound, thermal treatment of the solid reaction product in the reaction medium, separation and washing out of the solid body and its treatment with an electron donor, especially an ether, especially diisoamyl ether and finally, after further washing out, reaction with titanium tetrachloride.

The catalytic complexes are isolated by a third leaching process. The production of these catalytic complexes is therefore cumbersome and expensive as large quantities of washing solutions must be prepared (compare the published documents in Belgian patent no. 784,495) •

During the preparation of washing solutions for the recovery of the ether, large quantities of titanium-containing waste water are produced.

The invention relates to a method for producing a catalyst by reacting titanium tetrachloride with an aluminium-dialkyl chloride-containing organic aluminum compound in an inert hydrocarbon solvent, separating and washing the reaction product and subsequent thermal treatment of the reaction product suspended in the hydrocarbon solvent in the presence of an ether ( component A) and mixture 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 an organoaluminum compound containing an aluminum dialkyl chloride, the organoaluminum compound is at a temperature from -20 to +20°C

in an aluminum dialkyl chloride to titanium tetrachloride molar ratio of 0.8 1 to 1.5 : 1 to titanium tetrachloride and then feeding the suspension containing the solid washed reaction product to the thermal treatment in the presence of a dialkyl ether for a post-treatment with an aluminum alkyl halide, without previously separating the ether or one of the reaction products.

The invention further relates to the catalysts produced according to this method and their use for the polymerization of α-oil fines.

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

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 equimolecular mixture of aluminum dialkyl monochloride and aluminum alkyl dichloride, preferably aluminum ethyl sesquichloride, -propylsesquichloride, -isopropylsesquichloride or -isobutylsesquichloride. Of the sesquichlorides, aluminum ethyl sesquichloride is particularly preferred.

In the reaction of titanium tetrachloride with 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 having to the dissolved titanium tetrachloride. One works at a temperature of -20 to +20°C, preferably 0 to 5°C.

Wood is advantageously used as a solvent

the prescribed reaction temperature liquid alkane or cycloalkane,

such as hexane, heptane, octane, cyclohexane, a hydrocarbon mixture, such as, for example, a petrol fraction with a boiling range of 130 to 170°C or a solvent, as can be used for the polymerization of. α-olefins. The quantity of solvents is chosen so that the titanium tetrachloride is used in a 40 to 60 wt.-g solution, the aluminum organocompound in a 15 to 25 wt.-g solution.

The formed solid TiCl^-containing reaction product is separated and freed from all soluble substances by washing with the solvent used.

The reaction product is then suspended again in the hydrocarbon solvent in such an amount that the concentration of the titanium amounts to 0.5 to 2.5 mol, preferably 1.5 to 2.2 mol, TiCl-^/liter of solvent and subjected to the presence of a dialkyl ether for a thermal treatment. The thermal treatment is carried out at a temperature of 40 to 150°C, preferably 40 to 100°C, especially 60 to 90°C. Suitable dialkyl ethers are those with , 2 to 5 carbon atoms per alkyl group, for example diethyl ether, di-n-propyl ether, diisopropyl ether, di-n-butyl ether, diisobutyl ether, di-n-butyl ether is particularly suitable. The molar ratio of titanium trichloride to dialkyl ether during the thermal treatment is suitably 1:0.6 to 1:1.2, preferably 1:0.9 to 1:1.

Thereby, either the dialkyl ether can be added to the suspension or vice versa. During the thermal treatment, the dialkyl ether can be dissolved in a hydrocarbon solvent, but it is more advantageous to use this undiluted. Addition of the dialkyl ether to the suspension or addition of the suspension to the dialkyl ether can take place at the temperature for the thermal treatment within seconds to 5 hours, preferably from 1 to 30 minutes. After combining the reactants, the mixture is stirred for 5 to 300 minutes, preferably 30 to 60 minutes, at the thermal treatment temperature.

The suspension is then treated, without first separating the ether or one of the reaction products with an aluminum alkyl halide. Aluminum alkyl halides of the formula AlRnX^_n are suitable for this purpose, in which R means the alkyl residue with 2 to 8 carbon atoms, X a halogen atom and n a number from 1 to 2, preferably the aluminum dialkyl halides, -alkyl dihalides and -sesquihalides. Aluminum diethyl chloride, aluminum ethyl dichloride and aluminum ethyl sesquichloride are preferably used. A very economical method consists in using for this post-treatment the mother liquor formed during the preparation of the TiCl 2 -containing reaction product, which in particular contains aluminum alkyl dichlorides.

The molar ratio between aluminum alkyl halide and TiCl^ in the suspension to be treated is during the reaction 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 while stirring.

Advantageously, the post-treatment with the aluminum alkyl halide takes place in the presence of a small amount of a cyclopolyene. Suitable for this are norkaradiene 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. One preferably uses cycloheptatriene-(1,3j5), cyclooctatriene-(1,3,5) and cyclooctatetraene-(1,3,5,7) as well as their alkyl- and alkoxy-substituted derivatives, the alkyl group containing 1 to 4 carbon atoms, specifically . elt cycloheptatriene-(1,3,5) itself.

The molar ratio between titanium trichloride and cyclopolyene amounts to 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 is carried out with an aluminum alkyl halide in the presence of a cyclopolyene, the possible addition of a third catalyst component (component C) can be partially or completely omitted during the polymerization.

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 amount as mentioned above can be present or absent. Monoolefins with 2 to 10 carbon atoms are suitable. Ethylene, propylene, butene-(1) or 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 out with an inert hydrocarbon solvent. By using an aluminum dialkyl monohalide, on the other hand, the separation and washing out of catalyst component A can be avoided. 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.

After separation of the solvent by decantation or filtration, catalyst component A can be dried to the exclusion of air and moisture and then stored.

Catalyst component A according to the invention is 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 for the polymerization together with an aluminum dialkyl halide (= component B) of α-olefins. Of course, it is also possible to use the dry catalyst component A as such. The α-olefins are those with the formula CH2=CHR, in which R means an alkyl residue 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, but 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 the mixture of one of the α-olefins being at least 95% by weight and the content of ethylene a maximum of 5% by weight, each times referred to the total amount of monomers. Particularly noteworthy are mixtures of propylene with smaller 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 excellent impact resistance 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 from 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 a low-olefin petroleum fraction with a boiling range of 60 to 250°C, which must be carefully freed of 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 advantageously be carried out using α-olefins to be polymerized, for example in liquid propylene as dispersant.

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

The molecular weight is regulated, if necessary, by the addition of hydrogen.

The amount of catalyst component A depends on the prescribed reaction conditions, in particular on pressure and temperature. One usually uses 0.05 to 10 mmol TiCl^ per liter of solvent for suspension polymerization or reactor volume for gas phase polymerization, preferably 0.1 to 3 mmol TiCl-^.

Catalyst component B is an aluminum dialkyl monochloride with the formula AlF^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 TiCl^, amounts to 0.5 1 to 100: 1, preferably 1 1 to 10 1.

With this catalyst, consisting of components A and B, a high polymerization activity is achieved with 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 dispersant, soluble amounts of less than 3.0% by weight (referred to total polymer), preferably less than 2.0% by weight, are obtained. If the polymerization temperature is increased to 70 to 80°C, the undesired soluble amount increases to 6% by weight. On the other hand, a higher polymerization temperature is desirable for reasons of removal of polymerization heat.

Furthermore, it is also known that with increasing pressure and thus higher polymerization speed, the soluble amount increases. Thus • a polymerization of propylene in liquid propylene (around 32 kg/cm<2>, 70°C) always yields up to 6% of soluble amounts.

The inherently good stereospecificity of the two-component 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 discussed above, are suitable. Addition of component C to component A conveniently takes place together with component B at the beginning of polymerization. The molar ratio between component C and component A (calculated as TiClj) amounts to 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. Although a higher temperature is in principle possible, the amount of soluble atactic polymer is however greater.

During the post-treatment, according to the invention, with an aluminum alkyl halide of the TiCl-^-containing reaction product thermally treated with an inexpensive aliphatic dialkyl ether, 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 turnover rate by improved stereospecificity. In relation to the state of the art stated in British patent no. 895,595, at the same polymerization temperature and pressure, on the one hand, over 100% greater activity is found, and on the other hand, an improved stereospecificity. With the higher coiifeact activity (g polymer/g catalyst), a smaller amount of catalyst can be used for the polymerisation to achieve a corresponding rdmtime yield, whereby the laborious work-up is significantly facilitated or the same work-up leads to a better removal of the catalyst. During the polymerization. under elevated pressure, for example over 20 kg/cm<2>, which is either carried out 1 gas phase or 1 liquid α-olefin, for example liquid propylene, the yields are so large that a catalyst removal can be disregarded completely (yield over 1000 g p&lymer per 1 mmol TiCl-^).

The technical advance in relation to the state of the art stated in DOS 2,213,086 consists in the fact that the manufacture of the catalyst according to the invention is cheaper. The lower manufacturing costs are due to: 1. Savings of at least one, possibly even two of the necessary . three intense wash steps. 2. Lower investment and production costs for processing the washing solutions. 3. Material saving; for for the post-treatment according to the invention, either the mother liquor formed during the production of the reduced solid can be used or, by using aluminum dialkyl monohalide, the required amount of activator amount (component B) can be removed. 4. According to the state of the art, removal of the titanium tetrachloride used for further finishing by cleavage with water and neutralization leads to considerable amounts of waste water. In the catalyst production according to the method according to the invention, on the other hand, there is practically no titanium-containing waste water to be recovered.

E xample 1-14.

A. Kata lysator production.

Eel. Reduction of TiCl^seed using aluminum ethyl sesquichloride.

In a 10-litre mixing vessel, stir to exclude air

and moisture 1090 ml of a hydrogenated, oxygen-free petrol fraction (Kp 140 to 165°C) and 550 ml of titanium tetrachloride (3 mol) and at 0°C is added dropwise over the course of 8 hours with stirring (250 revolutions/minute) and nitrogen blanketing a solution of 1111.2 g aluminum ethyl sesquichloride (containing 4.5 mol aluminum diethyl monochloride) in 3334 g of the same 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.

After settling of the precipitate, the overlying mother liquor is decanted and the solid reaction product is washed out three times with 2000 ml of the petrol fraction each time. For further processing, the petrol fraction is suspended in such a quantity that a concentration of 2 mol TiCl-^/litre is achieved. Determination of the content of the suspension of trivalent titanium (such as TiCl^) takes place by titration with a Ce(IV) solution.

A.2. Thermal treatment of TiCl-^-containing reaction product in the presence of Di-n-butyl ether.

In a 2 liter mixing vessel, heat under exclusion of air

and moisture exclusion under nitrogen overlay 500 ml of the 2 molar above suspension (corresponding to 1 mol TiCl-^) to 85°C

and then at this temperature, while stirring, 161 ml di-n-butyl ether (equivalent to 0.95 mol) is added dropwise over the course of 30 minutes. The suspension is then held for 1 hour at 85°C. When ether is added, the mother liquor turns olive green.

A. 3. Post-treatment of TiCl-^-containing reaction product with aluminum alkyl halides.

Each time 100 mmol (TiCl^) of the above-mentioned olive-green suspension is post-treated under the conditions indicated in Table 1 with an aluminum alkyl halide. The finishing takes place at 35°C with stirring and nitrogen or argon overlay. After addition of alkyl halide, stirring is continued for another 1 hour at 35°C. Catalyst component A is used either unwashed or washed (3 to 5 times with the petrol fraction) as a suspension for the polymerization.

The TiCl^ content of the suspension is determined in advance and so much of this is taken that 1 mmol of TiCl^ is used each time.

(See Table 1).

B. P olymerization of propylene.

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 55°C with propylene. The quantities A1(C2H,_)2C1 (activator (component B)) given in table 2 are then added, and then each time so much of catalyst component A, the preparation of which was discussed under point A (see table 1), that each time 1 mmol TiCl^,. 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 polymerization Wed duration when 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 (C70°C) and dried in a vacuum at 70°C.

To determine the soluble amount (atactic polypropylene) formed during the polymerization, the polymerization mother liquor and the washing solution are combined in vacuum to dryness.

The polymerization results are listed in Table 2. Example 15.

A. Catalyst forward further.

The reduction of TiCl^ is carried out as indicated in example 1 A.l;

100 mmol TiCl^ is reduced. After deposition of the reaction product, the overlying mother liquor is separated and stored. After washing out the solid, the thermal treatment is carried out in a 2-molar concentration with 95 mmol of di-n-butyl ether, as stated in example 1 A.2. The final treatment of the suspension takes place with the mother liquor which contains the separated aluminum methyl dichloride and which is formed after the reduction of TiCljj. While stirring at 35°C, the mother liquor is added to the suspension over the course of 10 minutes and is then further stirred for 1 hour at 35°C. Catalyst component A is washed three times with an inert solvent.

B. P ol<y>merization of propylene.

The polymerization takes place as indicated in example 1 B using • the above-mentioned catalyst component A (1 mmol TiCl 2 ). The yield of insoluble crystalline polypropylene after a polymerization duration of 2 hours is 140 g. The volumetric weight is 460 g/liter and the RSV value is 3.8 dl/g. The polymerization mother liquor contains 2.79 g of soluble polypropylene (= 1.9 wt#).

Example 16.

P olymerization of propylene.

In a 150-litre enamel vessel heated to 60°C, equipped with stirrers, mantle heating and gas inlet pipes, while careful exclusion of air oxygen and moisture, 70 liters of a hydrogenated oxygen-free petrol fraction of boiling point 140 to 165°C are taken and saturated with propylene, then added under , nitrogen, a solution of 67 g of aluminum diethyl monochloride (560 mmol) (component B) in 203 g of the gasoline fraction.

After stirring for 15 minutes, 70 mmol (TiCl 2 ) of the suspension prepared therein* according to example 8 are added. The polymerization starts after a few minutes. After a rapid increase in pressure to 1.5 kg/cm<2> within 15 minutes when introducing propylene, such a quantity of propylene, which contains 0.15 volume hydrogen, is further introduced that this pressure is kept constant. The polymerization temperature is maintained by cooling, at 60°C. After a polymerization duration of 12 hours, the polymerization is interrupted by the addition of 1.4 liters of isopropanol. The reaction mixture is stirred for 2 hours at 60°C, then treated three times with 30 liters of water each time for 30 minutes and the aqueous layer is separated. After filtration, the solid is subjected to a 12-hour steam distillation with the addition of 0.05% by weight of an emulsifier (ethoxylated stearic acid). After separation from the aqueous suspension and drying in a vacuum, 30 kg of color-dissolved polypropylene powder is obtained (RSV value 3.4 dl/g, volume weight 508 g/l, bullet pressure hardness 820 kg/cm pThis corresponds to a yield of 430 g polypropylene per mmol TiCl^,

The soluble amount in the mother liquor is determined by evaporating a sample in a vacuum and amounts to 1.8% by weight referred to the total polymerizate.

Oak sample 17.

'Development of a propylene copolymer with statistically incorporated ethylene.

The polymerization is carried out similarly to example 16, in that to the introduced mixture of propylene and 0.1 vol.

of hydrogen, a quantity of 4.5 volumes of ethylene is added. Processing according to example 16 yields 28.7 kg of copolymer (RSV value 3.0 dl/g, volume weight 47.0 g/liter, bullet pressure hardness 590 kp/cm<2>) with an IR spectroscopically determined content of 2.8% by weight ethylene .

The content of soluble amount of mother liquor amounts to 3.1% by weight, referred to the total amount of copolymer.

The product can be processed into moldings and foils with very good transparency.

Example 18.

Sequential copolymerization of propylene and ethylene.

In a 150 liter vessel prepared according to example 16, filled with 100 liters of the hydrogenated oxygen-free petrol fraction, first 67 g of aluminum diethylmdnochloride (= 560 mmol) and then 200 mmol (TiClj) of the suspension prepared according to example 8 are added.

Then one introduces by a. polymerization temperature of 55°C for 5 hours propylene in a quantity of 5.5 kg/hour with a hydrogen content of 0.38 vol. After shutting off the monomer gas, the propylene pressure in the vessel is allowed to drop to 1.7 kg/cm<2>, which takes approx. 30 minutes. A gas flow of 3.25 kg/hour of ethylene is then introduced for 50 minutes.

The polymerization is interrupted by the addition of 1.4 liters of isopropanol and the mixture is worked up according to example 16. After drying, 28.3 kg of a polymer mixture is obtained, which essentially consists of polypropylene and a propylene-ethylene copolymer with statistical monomer distribution (RSV 2, 8 dl/g, volume weight 485 g/litre, bullet pressure hardness 66 kp/cm<2>, average shear strength at 23°C 24.3, at 0°C 15.2, at -20°C 9.9 kpcm/cm The mixture's IR - spectroscopically determined ethylene content amounted to 8.1% by weight.

In the mother liquor, 3.6% by weight of the ingas quantity of dissolved polymer is found.

Example 19.

Polymerization of propylene in liquid monomer.

A 16-litre enamel vessel, equipped with stirrers, mantle 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 is built up and through a sluice, a solution of 32 mmol A1)C2H,-)2C1 in 6 liters of liquid propylene and a suspension consisting of it to 4 mmol TiCl^ corresponding to according to example 8, table 1 prepared and isolated catalyst amount A and 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 experiment is interrupted after 6 hours when unpolymerized monomer is blown off. After drying, 5.2 kg of a well-flowable polymer with a volume weight of 530 g/litre is obtained. The RSV value is 2.9 dl/g. After 16 hours of extraction with heptane, a soluble amount of 7.8 wt# is determined. The bullet pressure hardness is 630 kp/cm<2> (DIN 53.456).

Example 20.

Polymerization of propylene in gas phase.

1.5 kg of polypropylene is placed in a horizontal 40 liter reactor with road-going pipes. The reactor is flushed with propylene by pressing and depressurizing several times and heated to 70°C. While stirring, a solution of 7.74 g of Al(C2H^)2C1 (64 mmol) in 23.1 g of a benzene fraction of Kp 140 at 165°C and 8 mmol (referred to TiCl^) of that according to example 8 is added , Table 1 prepared suspension; then 1.5 kg/hour of propylene is introduced and the temperature is maintained at 70°C. The pressure thereby increased at first rapidly, later more slowly. At a pressure of 20 kg/cm, the polymerization is interrupted (after approx. 9 hours). After the reactor has been de-stressed, 12 kg of colorless polypropylene is produced without further purification. Extraction with heptane yields 8% by weight of soluble polypropylene.

Example 21.

Polymerization of 4-methylpentene-(1)

In a 2 liter mixing vessel, equipped with a thermometer and assinn conduit, while excluding air and moisture, 1 liter of a hydrogenated, oxygen-free petrol fraction (boiling point 140 to 165°C) is taken, flushed with pure nitrogen. It is then added at a temperature of

50°C 8 mmol aluminum diethyl monochloride (= 0.97 ml) and 5 mmol (referenced by TiClj) of the suspension prepared according to example 8, table 1 and 200 g of 4-methylpentene-(1) are added dropwise over the course of 3 hours. The polymerization temperature is kept at 55°C. Polymerization starts after a few minutes. The polymer separates as a fine precipitate. After the addition has ended, 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 1 hour at 60°C, extracted with hot water and then sucked off hot. After thorough washing out with hot solvent (gasoline) as well as with acetone and drying in vacuum at 70°C, 193 g of colorless poly-4-methylpentene-(1) are obtained. The polymer showed a volume weight of 500 g/litre. In the mother liquor, the very small solution of 0.5% by weight is determined.

Examples 22-29.'

A. Catalyst production.

Eel. According to example 1 A.1 and A.2, a TiCl^-containing is prepared

A.2. suspension. A. 3. Post-treatment with an aluminum alkyl halide..

To 100 ml (= 200 mmol TiCl^) of the olive-green suspension, while excluding air and moisture at 35°C, 200 mmol aluminum diethyl monochloride (= 25}16 ml)' are added over 2 minutes and the mixture is stirred at 35°C for 1 hour. The catalyst component is used unwashed for the polymerization. In advance, the content of the suspension of trivalent titanium (such as TiCl^) is determined by titration with a Ce(IV) solution.

B. *'P olymerization of propylene.

In a 1 liter glass autoclave, have under the exclusion of

air and moisture 0.5 liter of a hydrogenated petrol fraction (boiling point 140 to l65°C) and saturated at 55°C with propylene. Next, the amount of A1(C2H^)2C1 (activator, component B) indicated in Table 3, newly distilled cycloheptatriene-(1,3,5) (as a 1 molar solution in the benzine fraction, component C) is introduced and then catalyst component A (each time 1 mmol TiCl^).

Hydrogen (0.25 kg/cm<p>) is then applied and during

5 minutes a total pressure is built up by introducing propylene

6 kg/cm<2>This pressure is maintained during the polymerization by

introduction 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 filter cake is washed on the filter with 1 liter of hot solvent (70°C) and dried in a vacuum at 70°C.

At a polymerization temperature greater than 60°C (see table 3), first polymerize for 10 minutes at 60°C and then first set the higher polymerization temperature.

Oak sample 30.

Polymerization of propylene in liquid monomer.

A 16 liter enamel vessel, equipped with stirrer, 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 a solution of 32 mmol A1(C2H,_)2C1 in 6 liters of liquid propylene and a suspension consisting of up to 4 mmol TiCl^ is added through a sluice correspondingly, according to example 1, - table 1 prepared isolated catalyst component A, as well as 2.4 ml of a molar solution of cycloheptatriene-(1,3,5) (component C) in hexane (2.4 mmol) and 6 liters of liquid propylene . It is then heated to 70°C, the pressure thereby increases to approx. 32 kg/cm During cooling, the internal temperature is kept at 70°C. The polymerization starts after a few minutes. The experiment is stopped after 6 hours when the vessel is relaxed. After drying, 4.9 kg of a well-flowable polymer with a volume weight of 540 g/litre is obtained. The RSV value is 2.5 dl/g. After 16 hours of extraction with heptane, a soluble part of 4.8 weight* is determined. Ball pressure hardness is 750 kp/cm<2> (DIN 53 456).

If the polymerization is carried out analogously with a catalyst that does not contain component C (cycloheptatriene-(1.355)) there is_in polypropylene a soluble part of 7.8% by weight* (compare example 19)•

Example 31.

A. Catalyst production.

Eel. Reduction of TiClj|by means of aluminum ethyl sesquichloride.

In a 10-litre mixing vessel, stir to exclude 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 are added dropwise during 8 hours with stirring (250 revolutions/minute)

and nitrogen overlay a solution of 1111.2 g of aluminum ethyl sesquichloride (containing 4.5 moles of aluminum diethyl monochloride) in 3334 g of the same gasoline fraction. A reddish-brown fine precipitate separates. The mixture is then stirred for 2 hours at 0°C and finally 12 hours at room temperature.

After settling of the precipitate, the overlying mother liquor is decanted and the solid reaction product is washed out three times with 2000 ml of the petrol fraction each time. For further processing, it is suspended in such a quantity of the petrol fraction that a concentration of 2 mol TiCl^/litre is achieved. Determination of the suspension's content of trivalent titanium (such as TiCl^) takes place by titration with a Ce(IV) solution.

A.2. Thermal treatment of TiCl^-containing reaction product, in the presence

of Di-n-butyl ether.

In a 2 liter mixing vessel, heat to the exclusion of

air and moisture under nitrogen overlay 500 ml of the 2 molar above suspension (corresponding to 1 mol TiCl^ to 80°C and then added dropwise at this temperature with stirring during 30 minutes. 16l ml Di-n-butyl ether (corresponding to 0.95 mol ).The suspension is then kept for 5 hours at 80° C. When the ether is added, the mother liquor turns olive green.

For the further processing of the TiCl^ suspension, it is diluted to a TiCl^ content of 0.5 mol/litre. Determination of the content of 3-valent titanium (as TiCl^) takes place by titration with a Ce(IV) solution.

A.3. Post-treatment of the TiC.l^-containing reaction product with aluminum alkyl halides and. a cyclopolyene.

To 10.0 ml of the petrol fraction, while excluding air and moisture, add 1 mmol (TiCl^) from the above-mentioned olive green suspension as well as 0.2 mmol cycloheptatrin-(1,3,5) and 2 mmol aluminum diethyl monochloride and then stir the mixture 1 hour at room temperature.

B• Polymerisation of propylene.

0.4 liters of a hydrated, oxygen-free petrol fraction (Kp 140 - 165°C) are placed in a 1 liter glass autoclave while excluding air and moisture and saturated with propylene at 55°C. 2 mmol of aluminum diethyl monochloride (activator (component B)) are then added and then the TiCl 3 suspension (1 mmol) post-treated according to point A 3 is added. 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 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. 237 g of dispersant-insoluble polypropylene is obtained. The volume weight of the well-flowable polymer powder is 524 g/litre, the RSV value is 2.8 dl/g and the bullet pressure hardness 800 kp/cm (DIN 53,456). To determine the soluble amount of (atactic) polypropylene formed during the polymerization, the polymerization mother liquor and washing solutions are combined and evaporated to dryness in a vacuum. 1.5 g of soluble polypropylene (= 0.62* referred to total polymer)' is obtained.

Oak sample 32.

The production of component A is carried out as indicated in example 31. However, in the post-treatment of the TiCl-^-containing reaction product (A.2.) an aluminum alkyl halide and a cyclopolyene are used instead of the cycloheptatriene-(1,3,5)cyclooctatetraene- (l,3,5,7)•

In 100 ml of the gasoline fraction, with the exclusion of air and moisture, 1 mmol (TiCl-^) of the olive-green suspension (Example 31, A.2.) 0.2 mmol cyclooctatetraene-(1,3,5,7) and 2 mmol aluminum diethyl monochloride and then the mixture is stirred for 1 hour at room temperature.

The polymerization of the propylene is carried out under the conditions specified in example 31. 242 g of insoluble polypropylene with a volumetric weight of 510 g/litre and an RSV value of 3.0 dl/g (bullet pressure hardness 820 kp/cm<2>) DIN 53456) are obtained in the dispersant. The quantity of soluble polypropylene amounts to 1.3 g (= 0.53*referenced).

to aggregate polymer).

Example 33.

Preparation of component A took place as indicated in example 31. The post-treatment of the TiCl^-containing reaction product (A2) with

aluminum alkyl halide and a cyclopolyene is carried out in the presence of a

olefin in the following way: 100 mmol of it according to example 31, A.2. prepared TiCl^-suspension is diluted by adding 800 ml of the benzene fraction to 0.1 mol TiCl-^pr. liters of dispersant and

while excluding air and moisture, 500 mmol of AKC^H^^ Cl (= 62.92 ml) and 40 mmol of cycloheptatriene-(1,3,5) 4.16 ml) are added 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 C^Hg). To prevent a vacuum from forming, the propylene is diluted with a small amount of argon. The TiCl 2 -containing catalyst suspension is then stirred for 1 hour at room temperature under argon. Determination of the content of 3-valent titanium (as TiCl-j) took place by titration with a Ce(IV) solution.

0.5 liters of a hydrogenated oxygen-free petrol fraction (boiling point 140 - 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 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. Further processing takes place as indicated in example 31. 220 g of dispersant-insoluble polypropylene is obtained. which has a translucent grain. The RSV value is 2.0 dl/g and the volumetric weight 505 g/litre and the bullet pressure hardness 850 kp/cm<2> (DIN 53456). In the mother liquor there are 4.5 g of soluble (atactic) polypropylene (2.0 weight* referred to total polymer).

Oak sample 34.

Polymerisation of propylene in volatile monomer..

A 16-litre enamel vessel, equipped with stirrer, mantle heating and gas introduction tube, 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 a solution is added through a sluice of 20 mmol A1(C2H^)2C1 in 6 liters of liquid propylene and then through a further gate 4 mmol (referred to TiCl^) of the suspension of component A prepared according to example, which contains 20 mmol A1(C2H^)2Cl, 1 .6 mmol 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 . 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, 3.8 kg of a well-flowable polymer with a volume weight of 55.0 g/litre is obtained. The polymer grain is translucent. The RSV value is 2.1 dl/g. By

After 16 hours of extraction with heptane, a soluble part is added

3.0 weight*. The ball compressive hardness is 780 kp/cm<2> (DIN 53456). Example 35.

5 mmol (TiCl-^) of the olive-green suspension prepared according to example 31 is suspended in the 500 ml gasoline fraction under . exclusion of air and moisture and then 10 mmol aluminum diethyl monochloride and 1 mmol cycloheptatriene(-1,3,5) are added, then the mixture is stirred for 1 hour at room temperature.

In a 2-litre mixing vessel, equipped with a thermometer and gas inlet pipe, 1 liter of a hydrogenated, oxygen-free petrol fraction (boiling point 140 to 165°C) is taken, 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 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, the mixture is stirred for 1 hour at 60°C, extracted with hot water and then sucked off hot. After thorough washing with hot solvent (gasoline) as well as with acetone and drying in vacuum at 70°C, 196 g of colorless poly-4-methylpentene-(1) are obtained.

The polymer has a volumetric weight of 520 g/litre. In the mother liquor there is the very small soluble part of 0.4 weight*.

Claims (5)

Process for producing a catalyst by reacting titanium tetrachloride with an organoaluminum compound containing an aluminum dialkyl chloride in an inert hydrocarbon solvent, separating and washing the reaction product and subsequent thermal treatment of the reaction product suspended in the hydrocarbon solvent in the presence of an ether (component A ) and mixing with an aluminum dialkyl halide (component B) and optionally with a cyclopolyene as stereoregulator (component C), characterized in that, for the production of component A, by reacting titanium tetrachloride with the organic aluminum compound containing an aluminum dialkyl chloride, the organic aluminum compound has a temperature of -20 to +20°C in a molar ratio of aluminum dialkyl chloride to titanium tetrachloride. of 0.8:1 to 1.5 1 to the titanium tetrachloride and then subjecting the solid washed reaction product-containing suspension to the thermal treatment in the presence of a dialkyl ether for a post-treatment with an aluminum alkyl halide. 2. Method according to claim 1, characterized in that the post-treatment is carried out with an aluminum alkyl halide in the presence of a cyclopolyene and/or an olefin. 3. Catalyst, produced by the method according to claim 1. 4. Use of the catalyst, produced according to the method according to claim 1, for the polymerization of α-olefins. 5. Process for the production of a polyolefin by polymerization of at least one α-olefin of the formula CH^CHR, in which R means an alkyl residue with 1 to 8 carbon atoms or copolymerization of 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, separation and washing of the reaction product and subsequent thermal treatment of it in hydrocarbon solvent suspended reaction product in the presence of an ether (component A), an aluminum dialkyl halide (component B) and optionally a cyclopolyene as 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 the reaction of titanium tetrachloride with an organoaluminum compound containing a aluminum dialkyl chloride is called the aluminum organic 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 and the suspension containing the solid washed reaction product is then subjected to the thermal treatment in the presence of a dialkyl ether for a post-treatment with an aluminum alkyl halide.