NO760061L - - Google Patents

Abstract

Process for the preparation of transition metal compounds.

Description

This invention relates to the treatment of compounds of transition metals, olefin polymerization catalysts containing

the such treated compounds and polymerization of olefins un-

where the use of such catalysts.

According to the present invention, a solid compound of a transition metal from groups IVA to VIA in the periodic table is ground with at least one sulfur-containing organic compound selected from sulfone compounds with the formula

sulfonamide compounds with the formula sulfide compounds with the formula

where X or each X independently of one another is a halogen atom, an alkyl, aryl, alkoxy, aryloxy, alkylthio or arylthio group'

or eh group -NRR', or two groups X may together form a saturated or unsaturated hydrocarbon ring;

Y or each Y is independently a halogen atom, a

alkyl, aryl, alkoxy, aryloxy, alkylthio or arylthio group or a group -NRR', or two groups Y can together form a met-

tight or unsaturated hydrocarbon ring; or a group X and a group Y can be replaced by a bond between the two phenyl groups attached to the -SC^ group, the bond being either direct or through a group -O-, -CH2~, -NR-, -S- or -C0-;

Z or each Z is independently of one another a halogen atom, an alkyl, aryl, alkoxy, aryloxy, alkylthio or arylthio group, or a group -NRR', or two groups Z can together form a saturated or unsaturated hydrocarbon ring;

D or each D is independently a halogen atom, an alkyl, aryl, alkoxy, aryloxy, alkylthio or arylthio group or a group -NRR1;

T is -S-, -O-, -NR'- or -C0-;

R is a hydrogen atom or a hydrocarbyl group;

R' is a hydrocarbyl group;

R" is a hydrocarbyl group or group

n, m, p and q are each independently an integer from 0 to 5; and

x is a positive integer.

In the transition metal compound, it is preferred that the metal has. a valence below its maximum. The transition metal can e.g. be zirconium or vanadium, but it is particularly preferred to use a titanium compound. It is preferred that the transition metal compound is a transition metal halide or -oxyhalide (e.g. VOC^) • °9 particularly a chloride, especially titanium trichloride. The term "titanium trichloride" shall be understood here to include not only pure titanium trichloride, but also titanium trichloride mixtures containing other materials, especially aluminum chloride or alkyl aluminum chlorides. Such forms of titanium trichloride are obtained by reduction of titanium tetrachloride with aluminum metal or an organo-aluminum compound. Materials of the titanium trichloride/aluminium chloride type, which can be obtained by reducing titanium tetrachloride with aluminum metal, are particularly preferred.

In the sulfone compounds, both m and n can be zero, when the compound is diphenyl sulfone. Alternatively, m is one and n is zero or m and n are both one. Compounds where more one and n are zero include 4-(phenylthio)diphenylsulfone(dg 4-(phenoxy)diphenylsulfone. Compounds where both m and n are one include 2,4'-(diphenoxy)-diphenylsulfone; 4, 41-(diphenoxy)diphenylsulfone; 4,4'-dichlorodiphenylsulfone and 4,4'-(dimethyl)diphenylsulfone. 2,4,4'-.(trimethyl)diphenylsulfone is a compound where m is two and n is 1. 6-Phenylsulfonyltetralin is an example of a compound in which two groups X together form an unsaturated hydrocarbon ring; in such a compound m is two and n is zero. Di-benzothiophene-5,5-dioxide is an example of a compound in which X and Y are replaced by a direct bond between the two phenyl groups attached to the -SO2 group. Phenoxathine-10,10-dioxide is an example of a compound where X and Y are replaced by a bond through a group -O- between the two phenyl groups bonded to the -SO2~ group Thioxanthene-10,10-dloxide is an example of a compound where X and Y are replaced by a bond through a -CH2~ group between the two phenyl groups b unted to the -SO2 group, and in 10-methylphenothiazine-5,5-dioxide X and Y are replaced by a bond through a group -N-(CH-j)-. In the sulfonamide compounds, when p is zero, the compound is a benzenesulfonamide derivative such as N,N-dimethyl-benzenesulfonamide, N,N-diethyl-benzenesulfonamide or N,N-diphenyl-benzenesulfonamide. When p is one, the group Z can e.g. be a bromine or chlorine atom or a phenoxy group. The groups R' and R" are the same or different and can be, for example, methyl, ethyl or phenyl groups as in N-methyl-N-phenyl-4-bromobenzenesulfonamide, N-methyl-N-phenyl-4-chlorobenzenesulfonamide and N,N-diethyl-4-phenoxybenzenesulfonamide. Alternatively, the group R" can be a group

e.g. the group N-methyl-N-benzenesulfonylaminoethyl, An example of such a compound is N,N'-dibenzenesulfonyl-N,N1 - dimethyl-1,2-diaminoethane,

In the sulfide compound, when each q is zero, the compound is phen-oxathine, thianthrene, or an N-hydrocarbyl-phenothiazine such as

N-methylphenothiazine.

For practical reasons, the term "organosulfur compound" will be used in the following as a term for sulfur-containing organic compounds with one of the stated formulas.

Grinding of the solid transition metal compound and at least one organosulfur compound is preferably carried out using a molar excess of the transition metal compound. In general, it is preferred to grind the solid transition metal compound with from 5 to 100% molar amount, relative to the transition metal compound, of at least one organosulfur compound. It is particularly preferred that the transition metal compound is ground with from 10 to 50% molar amount of an organosulfur compound.

However, it should be noted that the effect of the organosulfur compound. will be affected by the nature of the organosulfur compound, and the preferred amount of the organosulfur compound will thus vary according to the organosulfur compound used. It should also be noted that the nature of the solid transition metal compound also influences the effect and thus the preferred amounts of the organosulfur compound. Thus, if the solid transition metal compound is titanium trichloride, the preferred amounts of the organosulfur compound are higher if this is the product obtained by reducing titanium tetrachloride with aluminum metal than if the product obtained by reducing titanium tetrachloride with titanium metal or hydrogen is used.

In addition to the solid transition metal compound and the organosulfur compound present during the painting, it is preferred that a Lewis acid compound is also present, the Lewis acid compound being different from the solid transition metal compound. The Lewis acid can e.g. be aluminum chloride or preferably titanium tetrachloride. The Lewis acid can be added separately or can be added as a complex with the organosulfur compound. If a complex of Lewis acid and the organosulfur compound is used, additional uncomplexed Lewis acid or organosulfur compound can be added during painting. Alternatively, painting can be carried out in the presence of at least one oxidizing agent. The oxidizing agent may be such that it forms a Lewis acid compound from the solid transition metal compound. Suitable oxidizing agents include oxygen gas or halogen-containing materials such as chlorine gas, carbon tetrachloride, hexachlorocyclopentadiene, tin (IV) chloride, phosphorus pentachloride and iodine.

The amount of Lewis acid present is preferably less than the amount of solid transition metal compound and may range from 1 to 50% molar amount, particularly from 5 to 40% molar, e.g. 10% molar, in relation to the amount of solid transition metal compound. The preferred quantity ratios of the Lewis acid compound, however, depend on the particular Lewis acid compound ■ used and also on the organo-sulphur compound. The amount of oxidizing agent used is typically in the range from 0.2 to 50% molar amount, preferably from 1 to 30% molar, in relation to the amount of the solid transition metal compound. However, preferred proportions for any oxidizing agent depend on the nature of the oxidizing agent and also on the organosulfur compound.

According to a preferred feature of the invention, a solid compound of a transition metal from the groups ]jVA to VIA in the periodic table, where the metal has a valence below its maximum, preferably titanium trichloride, with from 5 to 100% molar amount, preferably from 10 to 50% molar, relative to the solid compound of the transition metal, of at least one sulfur-containing organic compound selected from sulfone compounds of the formula

sulfonamide compounds with the formula sulfide compounds with the formula

where D, R', R", T, X, Y, Z, m, n, p and q are as indicated above,

and from 1 to 50% molar amount, preferably from 10 to 40% molar, relative to the solid transition metal compound, of at least one Lewis acid compound that is different from the solid transition metal

metal compound, preferably titanium tetrachloride.

It should be noted that the Lewis acid compound can be a material that is formed during the painting and not necessarily a material that is added separately to the measuring device. If the Lewis acid is formed from the solid transition metal compound, the amount formed must be expressed in terms of the number of moles of remaining solid transition compound, as it is this remaining amount that is present after grinding is completed.

Preferred organosulfur compounds include 4-(phenoxy)diphenylsulfone; 4,4'-dichlorodiphenylsulfone or especially 4,4'-(dimethyl)-diphenylsulfone, diphenylsulfone, N,N-diethyl-4-phenoxy-benzenesulfonamide, N,N-diphenyl-benzenesulfonamide, phenoxatine, phenoxatine-10,10-dioxide or thioxanthene-10,10-dioxide.

The grinding is suitably carried out using a ball mill, and it is preferred that the main part of the grinding is carried out in a dry state, i.e. in the absence of added solvents and suspending liquids. The materials to be ground can be introduced into the mill or other measuring device either in the absence of solvents or as a solution or suspension in a suitable inert diluent which is then removed either by heating, reducing the pressure or both. The painting can be carried out at any suitable temperature, and satisfactory results have been obtained by painting at ambient temperature (approx. 20-25°C), although it will be understood that higher or lower temperatures can possibly be used, e.g. from -50 up to 50°C. Grinding is carried out for any suitable time, and when a ball mill is used which provides a tumbling effect, grinding time can be from 5 to 100 hours or more, e.g. from 24 to 72 hours, is used. It will be understood that the grinding time will depend on the intensity of the grinding, and when a rotating ball mill is used, the time will depend on the material, the size and number of balls used and the speed of rotation of the ball mill. Other measurement methods can be used, e.g. grinding in a vibrating mill, and when using such other methods, different times and temperatures for grinding may be preferred.

The milled product can be removed from the measuring apparatus as a dry, solid substance, but this can be made easier by adding a suitable liquid medium, especially an inert organic liquid such as a

aliphatic hydrocarbon, and the fine solid is washed out as a suspension in the liquid medium. An appropriate method is to

add a suitable inert, liquid medium to the mill and its contents

and to continue the painting process for a short time of preferably not more than 30 minutes and in particular from 5 to 20 minutes. The suspension thus obtained is easily removed from the mill, and remaining quantities can be washed out using further quantities of the inert liquid medium. A rapid reduction of the particle size of the solid appears to occur during the wet grinding stage, and to avoid unwanted particle size reduction, it is preferred to carry out the wet grinding for only a relatively short time.

The ground transition metal compound is particularly suitable as a component of an olefin polymerization catalyst.

According to a further feature of the invention, an olefin polymerization catalyst is thus provided comprising: 1) a transition metal compound which is the product of grinding a solid compound of a transition metal from groups IVA to VIA in the periodic table (component A) with at least one sulfur-containing organic compound selected from sulfone compounds of the formula

sulfonamide compounds with the formula sulfide compounds with the formula

where

D, R', R", T, X, Y, Z, m, n, p and q are as indicated above (component B); and 2) at least one organometallic compound of aluminum or of a non-transition metal from group IIA in the periodic table, or a complex of an organometallic compound of a non-transition metal from group IA or IIA of the periodic table and an organo-aluminum compound.

Component (1) in the catalyst is a material that is obtained by grinding a solid transition metal compound together with an organosulfur compound in the manner described above, and it will be understood that component (1) includes materials that are obtained by carrying out the grinding in presence of also at least one Lewis acid compound (component (1)C), or at least one oxidizing agent (component (1)D).

Component (2), the organometallic compound, can

be a Grignard reagent which is almost ether-free, or a compound of the type Mg(CgH5)2. Alternatively, component (2) can be a complex of an organometallic compound of a metal

from groups IA or IIA, such as e.g. Mg(AlEt4)2 or a lithium aluminum tetraalkyl compound. It is preferred that component (2) is an organo-aluminum compound such as a bis(dialkylaluminium)oxyalkane, a bis(dialkylaluminum)oxide, an aluminum hydrocarbyl sulfate, an aluminum hydrocarbyloxyhydrocarbyl or especially an aluminum trihydrocarbyl or dihydrocarbyl aluminum hydride or -halide, in particular aluminum triethyl or diethyl aluminum chloride, since catalysts containing aluminum triethyl give a high polymerization rate, while catalysts containing diethyl aluminum chloride give a relatively high percentage yield of the desired insoluble (isotactic) polymer. A mixture of compounds can optionally be used, e.g. a mixture of an aluminum trialkyl and an aluminum dialkyl halide. It may be preferable to use catalysts which give a small amount of residual halogen in the polymer product, and component (2) is then suitably a halogen-free compound, in particular an aluminum trihydrocarbyl.

In addition to components (1) and (2), the catalyst may contain a further component which is at least one organo-Lewis base compound (component (3)). The organo-Lewis base compound may be any such Lewis base effective to alter the activity and/or stereospecificity of a Ziegler catalyst system. A number of such Lewis bases have been proposed which have such an effect, and these include ethers; esters such as methyl methacrylate; ketones; alcohols; the sulfur-containing analogues of ethers, esters, ketones and alcohols; organosilicon compounds such as silanes and siloxanes; amides such as formamide; urea and thiourea and the substituted derivatives thereof such as N,N,N',N'--tetramethylurea f ; alkanolamines such as (N,N-dimethylamino)ethanol; amines such as triethylamine and tributylamine; cyclic amines such as pyridine, quinoline and substituted derivatives thereof such as α-picoline; diamines such as N ,N ,N ' ,N 1 -tetramethylethylenediamine; and organic phosphines, phosphine oxides, phosphites and phosphates such as triphenylphosphine, triphenylphosphine oxide, triethylphosphite and triethylphosphate. as an organo-Lewis base compound, it is particularly preferred to use secondary or tertiary amines, such as dibutylamine or tributylamine, diamines such as N,N,N',N'-tetramethylethylenediamine, and compounds containing both phosphorus and nitrogen atoms, such 'as hexamethylphosphoric acid triamide; N,N,N',N'-tetramethylethyl phosphordiamidate; N,N,N',N',N"-pentamethyl-N"-[3-dimethylaminoethyl phosphoric acid triamide; 2-dimethylamino-1,3-dimethyl-1,3,2-diaza-phospho- • lidine-2-oxide and octamethyl pyrophosphoramide.

Use of organo-Lewis base compounds or complexes containing organo-Lewis base compounds in olefin polymerization ion catalysts is, among other things, described in British patents

803 198; 809,717; 880998, 896 509, 920 118, 921 954,

933 236, 940 125, 966025, 969074, 971 248, 1 013 363, 1 017 977, 1 049 723, 1 122 010, 1 150845, 1 208 815, 1 234 657, 15 37 38 33 15 and 133331 15 207; Belgian patent 693 551 and German publication 2 329 723.

In our British patent application 7989/73, the use of organo-phosphine oxide derivatives is described where at least one group which is bound to the phosphorus atom is a heterocyclic group containing more than 3 atoms, preferably five or six atoms, in the ring which is bound to the phosphorus atom by a carbon or heteroatom.

In our British patent application 7988/73, the use of a Lewis base is described which is an organo-phosphine oxide where the phosphorus atom is included, together with 3 other heteroatoms, in an endocyclic ring system. The compounds described in these patent applications can also be used as organo-Lewis base compounds.

In addition to or instead of the organo-Lewis base compounds, the catalyst can also contain a substituted or unsubstituted polyene (component (4)), which can be an acyclic polyene such as 3-methylheptatriene (1,4,6) or a cycl-

lysed polyene such as cyclooctatriene, cyclooctatetraene or cycloheptatriene or derivatives of such polyenes such as alkyl- or alkoxy-substituted polyenes; tropylium salts or complexes,

tropolone or tropon.

The quantity ratio of the different catalyst components can be varied to a large extent depending on the materials used and the absolute concentrations of the components. However, for each molecular part of the solid compound of a transition metal present as component (1)(A) in the catalyst, there is generally present at least 0.05 and preferably at least 1.0 molecular parts of component (2), but it may be desirable to use much larger amounts of component 2), e.g. as much as 50' molecular parts or more, for each molecular part of the transition metal compound. In general, it is preferred to use no more than 25, and in particular no more than 10 molecular parts of component 2), for each molecular part of the solid transition metal compound. The amount of organo-Lewis base compound, which is the optional component 3), is in the range from 0.01 to 10, preferably from 0.05 to 5.0 and especially<1>from 0.2 to 2 molecular parts for each molecular portion of the solid transition metal compound that is present as component 1)(A) in the catalyst and the amount of component 3) is less than the amount of component 2). A polyene which is present in the catalyst should preferably be present in a molar amount which is smaller than the molar amount of component 2) in the catalyst. For each molecular part of component 2), the molecular amount of polyene is suitably in the range from 0.01 to 1.0, in particular 0.05 to 0.5, e.g. 0.2.

If the catalyst contains both components 3 and 4, the molecular amount of the organo-Lewis base compound which is component 3 and the polyene should preferably be less in total than the molecular amount of component 2 in the catalyst. If the catalyst contains both components 3 and 4, these can conveniently be used in equimolar amounts, but the relative amounts of these components can be varied to give an optimal result.

A preferred catalyst according to the invention comprises: 1) a titanium trichloride-containing material obtained by grinding (A) a titanium trichloride/aluminum trichloride material in the presence of (B) from 5 to 100% molar amount, preferably from 10 to 50% molar, in relative to the titanium trichloride, of at least one sulfur-containing organic compound selected from sulfone compounds of the formula

sulfonamide compounds of the formula

sulfide compounds with the formula

where

D, R', R", T, X, Y, Z, m, n, p and q are as indicated above, and (C) from 1 to 50% molar amount, preferably from 10 to 40% molar , relative to the titanium trichloride, of at least one Lewis acid compound which is not titanium trichloride, preferably titanium tetrachloride;

2) at least "one organo-aluminum compound; and

3) - at least one organo-Lewis base compound.

It is preferred to wash component (1) with a suitable inert liquid such as an inert hydrocarbon or halohydrocarbon, before it is mixed with the other catalyst components. Alternatively, component (1) can be heated, possibly in the presence of an inert liquid, to a temperature in the range from 60 to 200°C. The heating step and the washing can be combined by washing component (1) with an inert liquid at a temperature in the range from 60 to 200°C.

The Lewis base which is component (3) of the catalyst is conveniently hexamethylphosphoric acid triamide; 2-dimethylamino-1,3-dimethyl-1,3,2-diazaphospholidin-2-oxide; N,N,N',N',N"-pentamethyl-N"-fi-dimethylaminoethyl phosphoric acid triamide; tetramethylethylenediamine or tributylamine.

The catalysts according to the invention are particularly suitable for the polymerization and copolymerization of olefin monomers by bringing at least one olefin monomer into contact with a catalyst of the type described above.

More particularly, there is provided a method for producing a polymer or copolymer of an olefin monomer wherein at least one olefin monomer is contacted with a polymerization catalyst containing: 1) a transition metal component obtained by grinding a solid compound of a transition metal from groups IVA to VIA in the periodic table (component A), together with at least one sulfur-containing organic compound selected from sulfone compounds of the formula

sulfonamide compounds of the formula:

sulfide compounds with the formula-:

where

D, R', R", T, X, Y, Z, m, n, p and q are as indicated above (component B), and optionally at least one Lewis acid compound which is different from the solid transition metal compound, preferably titanium tetrachloride (const

C) ; and

2) at least one organometallic compound of aluminum or of a non-transition metal from group IIAi of the periodic table or a complex of an organometallic compound of a non-transition metal from group IA or IIA of the periodic table and an organo-aluminum compound; and eventually

3) at least one organo-Lewis base compound; and or

4) a substituted or unsubstituted polyene.

Any olefin monomer, in particular raono-α-olefin monomer, which can be polymerized using a Ziegler catalyst, can be polymerized by the process according to the invention. Monomers which can be polymerized by the present method thus include butene-1 and 4-methylpentene-1 and especially propylene. These plefins can be copolymerized together, but it is preferred to copolymerize with ethylene, conveniently using a sequential polymerization, such as described in British Patents 970,478, 970,479 and 1,014,944.

It has been found that the method according to the invention can be used for the polymerization of propylene to give a high yield of polymer in relation to the amount of catalyst used and also a relatively small proportion of undesired soluble polymer.

It is well known that catalysts of the Ziegler type are susceptible to the effects of contaminants, and the activity and stereospecificity of such catalysts can be adversely affected by the presence of small amounts of contaminants, particularly oxygen and polar compounds such as water and alcohol in the monomer and/or the diluent when this is used. For the polymerization of olefin monomers using Ziegler catalysts, it is thus known to use pure monomers and diluents. However, when the catalysts according to the invention are used, these can be used in smaller quantities than the usual catalysts of the Ziegler type and are thus more exposed to any contaminants present in the system. For use with the catalysts according to the present invention, it is therefore desirable that the monomers and any diluents of commercial purity are subjected to further purification.

The cleaning treatment can possibly be carried out in more than one step. The particular purification treatment used will depend on the purity of the starting materials.

Satisfactory purity can in most cases be achieved by passing the monomer (and the diluent if such is used) through a layer of a material which can absorb the impurities present in the monomer and the diluent, e.g. as described in British Patents 1,111,493 and 1,226,659.

Using catalysts according to the present invention, polymerization can be carried out in the presence or in the absence of an inert diluent such as a suitably purified paraffinic hydrocarbon. If a diluent is not used, polymerization can be achieved in the liquid phase using excess liquid monomer as a suspension medium for catalyst and polymeric product. If the monomer is used in the gas phase, polymerization can be accomplished using any technique suitable for performing gas-solid conversion, such as a fluidized bed reactor system or a ribbon mixer type reactor.

Polymerization can either be carried out batchwise or continuously. The catalyst components can be introduced into the polymerization vessel separately, but it is preferred, especially if the polymerization is to be carried out continuously, to mix all the catalyst components together before they are introduced into the polymerization reactor. In a batch process, it is possible not to add all the catalyst at the beginning of the polymerization. thus, a portion of the catalyst can be added to initiate the polymerization, and further amounts of one or more of the catalyst components are added one or more times during the polymerization. Conveniently, at least 25% of each catalyst component is added to initiate the polymerization, and the remaining catalyst components are added during the polymerization. As the addition of one slurry of solid material may be inappropriate, it may be preferred that all of the transition metal compound be added, together

but with some of each of the other catalyst components, to initiate the polymerization, and the rest of the other catalyst components are added during the polymerization. It is desirable that when mixing the catalyst components, the solid transition metal compound is not allowed to come into contact with any organo-Lewis base compound that is present as component (3) in the absence of the organometallic compound that is component (2) in the catalyst.

The polymerization can be carried out in the presence of a chain transfer agent such as hydrogen or a zinc dialkyl compound,

to regulate the molecular weight of the product formed. If hydrogen is used as chain transfer agent, it is suitably used in an amount of from 0.01 to 5.0%, in particular from 0.10 to 2.0% molar amount in relation to the monomer. The amount of chain transfer agent will depend on the polymerization conditions, in particular the temperature, which is typically in the range from 20 to 100°C, in particular from 50 to 80°C.

Using catalysts according to the invention, it has been possible to polymerize propylene to obtain

a high yield, in relation to the amount of transition metal compounds

those present in the catalyst, of a polymer with a high flexural modulus.

When a catalyst containing titanium trichloride is thus used, a propylene polymer can be obtained where the titanium content in the polymer from the remaining catalyst in the polymer is no more than approx. 100 parts per million (dpm), by weight, and the flexural modulus of the polymer is at least 1.00 GN/m<2>.

The flexural modulus of the polymer is the modulus as measured by the apparatus described in "Polymer Age", March 1970, pages 57 and 58 at 1% skin tension after 60 seconds at 23°C and 50% relative humidity using samples prepared as in Example 81.

The titanium content in the polymer can be determined by any suitable analytical technique, and we have found X-ray fluorescence spectrometry to be a particularly suitable analytical technique.

Using the present method, polymers, in particular propylene homopolymers, can be produced which have a flexural modulus of at least 1.30 GN/m 2 .

Polymers according to the present invention have

a high molecular weight as shown by the melt index measured according to ASTM Test Method D 1238-70, using "Condition N"

(ie a temperature of 190°C and a weight of 10 kg). Polymers according to the present invention have a melt index of less than 200. Preferred polymers have a melt index of less than 100, especially less than 50, e.g. between 5 and 50.

The following examples shall serve to further illustrate the invention.

EXAMPLE 1.

Into a stainless steel mill with a length of 15.2 cm and a diameter of 7.9. cm and provided internally with four metal strips, 200 stainless steel balls with a diameter of 12.7 mm and 200 stainless steel balls with a diameter of 6.35 mm were introduced. The mill was closed, evacuated to 0.2 mm Hg and flushed with nitrogen to provide a nitrogen atmosphere in the mill. A 20% molar amount (in relation to the amount of Ticl^ which was then added) of diphenylsulfone was added to the mill which was evacuated and flushed with nitrogen again. About. 20 g of titanium trichloride (stauffer-AA) was introduced as a solid into the mill which was shaken manually. Finally, a 10% molar amount (based on the Ticl3 content of Stauffer AA) of titanium tetrachloride was introduced into the mill from an injection syringe. This addition was made over a period of 2 minutes, while the mill

was rotated, and this technique provides an even distribution of the titanium tetrachloride in the mill. When all the additive had been introduced into the mill, it was rotated at 120 revolutions per minute. minute for 64 hours.

The mill's temperature was regulated by spraying water at a temperature of 20°C continuously over the mill.

After grinding for 64 hours, 100 ml of an inert hydrocarbon diluent, with a boiling range of approx. 170 to 180°C, added, and milling continued for another 15 minutes. The resulting slurry was transferred to a holding tank and the mill was washed four times with 50ml portions of the same inert hydrocarbon diluent. The washing liquids were transferred to the storage tank.

EXAMPLES 2 TO 25. •

A further series of grindings was carried out using the same general technique as described in Example 1, but in some cases TiCl 4 was omitted, or aluminum chloride was used instead of TiCl 4 ”. Details for all grindings.

(including Example 1) are listed in Table 1 together with some comparative experiments (identified by letters) where the titanium trichloride was milled alone or together with an alkyl sulfone compound.

Footnote to Table 1

a) DPS is diphenyl sulfone

DMDPS is 4,41-(dimethyl)-diphenyl sulfone.

DBTD is dibenzothiophene-5,5-dioxide. . DCDPS is 4,4'-dichloro-diphenyl sulfone.

PDPS is 4-(phenoxy)-diphenyl sulfone.

DSDDA is N,N<1->dibenzenesulfonyl-N,N'-dimethyl-1,2-diaminoethane.

DMBS is N,N-dimethylbenzenesulfonamide.

DEPBS is N,N-diethyl-4-phenoxybenzenesulfonamide. TMDPS is 2,4,4'-trimethyl-diphenyl sulfone.

DÉBS is N,N-diethylbenzenesulfonamide.

DPBS is N,N-diphenyl-benzenesulfonamide.

POT is fenoxatin.

TAT is tiantrene.

POTDer phenoxatiin-lo,10-dioxide.

TADs thioxanthene-10,10-dioxide.

MPT is N-methylphenothiazine.

MPTDer 10-methylphenothiazine-5,5-dioxide.

MPS is methyl-phenyl-sulfone.

BPS is t-butyl-phenyl-sulfone.

EXAMPLES 26 TO 49

The titanium trichloride products of Examples 1 to 25 and the Comparative Examples were used to polymerize propylene.

The propylene used for the polymerization was purified by passing gaseous propylene through a column

(7.6 cm in diameter, 91 cm long) containing 1.6 mm grain of

Alcoa Fl alumina at 50-60°C, and then through a corresponding column containing BTS catalyst (copper (II) oxide reduced to finely divided metallic copper on a magnesium oxide carrier) at 40-50°C, condense the off-gas and pass the liquid propylene through four columns (all 7.6 cm diameter; two 91 cm long, two 183 cm long) at 25°C, each containing 1.6 mm pellets of UnionCarbide 3A molecular sieve.

This treatment reduced the water content of the monomer from

5 to 10 dpm, depending on volume, to <1 dpm,. by volume, and the oxygen content from 1 to 2 dpm, by volume, to ^0.5 dpm, by volume. The amount of inert compounds (nitrogen, ethane, etc.) was unchanged at 0.3%, and the amount of unsaturated hydrocarbons (allene, methyl-acetylene, etc.) was unchanged at <C1 dpm.

A polymerization flask equipped with an efficient stirrer and

a water jacket was carefully dried, and 1 liter of an inert hydrocarbon diluent with a boiling range of approx. 170-180°C was introduced. The diluent was evacuated at 60°C, purged with nitrogen and evacuated, and this treatment effectively reduced the water and oxygen content of the diluent to below 10 dpm, by weight. The diluent was then saturated with purified propylene to a pressure of one atmosphere. Eight millimoles of triethylaluminum were introduced, followed by 4 millimoles of hexamethylphosphoric acid triamide. After half an hour, 2 millimoles of TiCl-^, obtained as described in the previous examples, were introduced. The pressure in the reaction vessel was maintained at 1 atmosphere by supplying propylene from a burette. After a period of 2.5 hours from the introduction of Ticl-2z, the experiment was terminated with 10 ml of isopropanol, and a sample of the liquid on top was extracted to determine the concentration of soluble polymer dissolved in the polymerization diluent. The solid was filtered and washed three times with petroleum ether and dried in a vacuum oven at 120°C for 1 hour. The yield of solid plus calculated soluble polymer agreed, allowing for experimental errors, with the propylene loss from the borough.

The results are shown in table 2, where the comparison examples are denoted by letters.

Footnote to table 2

b) The number or letter refers to the example or comparison example that describes the grinding of the TiCl3 component. c) Based only on solid polymer in relation to the Ti.Cl3 content in the catalyst. d) % based on total polymer (solid + soluble) formed.

EXAMPLES 50 TO 74

Polymerizations were carried out over a period of 3 hours using the procedure generally described in Examples 26 to 49. The propylene used contained 0.12 molar percent hydrogen relative to the propylene. millimoles of a titanium trichloride material. The results are shown in Table 3. '

Footnote to table 3

b), c) and d) - See table 2.

EXAMPLES 75 TO 77

The painting described in Example 1 was repeated, and a sample

of the ground product was washed with toluene.

The washing was carried out by leaving a slurry, containing approx. 100 mmol of the titanium chloride, settle out. The liquid on top was removed using a syringe. The solid was resuspended at room temperature in 100 ml of toluene, which had been dried with sodium and flushed with nitrogen.

stirred for 15 minutes, allowed to settle, and the liquid on top was removed by syringe. This procedure with toluene was repeated two more times, and the solid was resuspended in 200 ml of toluene.

The washed and unwashed titanium trichloride materials were used to polymerize propylene using the process of Examples 50 to 74. A product obtained by washing, in the manner described above, the product obtained according to Example 20 (namely grinding in the presence of Ticl and phenoxathiine) were also used to polymerize propylene. The results are reproduced in example 4.

Footnote to table 4

c) and d) - See table 2

e) TiCl^-^S is the unwashed product obtained by repeating example 1.

Ticl3~76 is the product obtained by washing Ticl3~75 with toluene.

TiCl2_77 is the product obtained by washing the ground product from example 20 with toluene.

EXAMPLES 7 8 to 80

The procedure of Examples 50 to 74 was repeated, except that hexamethylphosphoric acid triamide was omitted from the catalyst, which contained 1 millimole of tri(n-butyl)amine, and the polymerization time was 4 hours. The results are reproduced in table 5.

Footnote to table 5:

a), c) and d) - See table 2.

e) - See table 4.

f) In this experiment, all the catalyst components were mixed together in toluene and shaken for 1 hour before being introduced into

the polymerization vessel.

EXAMPLE 81

One. sample Ticl3-76 (as defined in the footnotes to Table 4) was used to produce polymerization of liquid propylene.

The polymerization was carried out in a stainless steel autoclave with a total capacity of 8 liters, which was equipped with a water circulation jacket and a vertical stirrer of the anchor type. The autoclave was heated to 70°C, evacuated, and the vacuum released with propylene (cleaned as in Examples 17 to 32). The autoclave was then evacuated again, and the process was repeated five times, and the autoclave was finally brought to a pressure of 0.136 ato with propylene gas at 25°C. A heptane solution containing 50 gram-millimoles of diethylaluminum chloride was added to the autoclave, followed by 2 gram-millimoles of the washed titanium trichloride material, TiCl 2 -^ . 5 liters of liquid propylene were added to the autoclave immediately after the addition of titanium trichloride, and the stirrer was operated at a speed of 150 revolutions per minute. minute. The propylene addition was carried out by allowing 5.5 liters of liquid propylene to flow in from a burette at 50°C into the autoclave. Hydrogen (250 gram-millimoles) was added and the temperature of the autoclave contents was raised to 65°C over 10 minutes. The hydrogen was commercially available hydrogen (99.99% pure) which was further purified by passing it through a column (about 20 cm in diameter and 120 cm long) containing a molecular sieve material (UnionCarbide 3A) at 20°G. The hydrogen was stored in the sieve column and tapped off as needed. The polymerization was allowed to proceed at a temperature of 65°C and a pressure of 30 ato. More hydrogen (48 gram-millimoles in each case} was added every 30 minutes , and 7 such hydrogen additions were made. After polymerization for 4 hours, the autoclave was vented over a period of 10 minutes to remove unpolymerized propylene, and a free-flowing pale pink powder was obtained.

A polymer yield of 565 grams per millimoles of titanium nominally present in the catalyst was obtained. The polymer had a melt index of 6 (measured by ASTM Test Method D1238-70, Condition N, ie at 190°C and 10 kg).

The flexural modulus of the polymer was 1.34 GN/m 2 . The flexural modulus was measured using a cantilever beam apparatus as described in Polymer Age, March 1970, pages 57 and 58. The deformation

of a test strip at 1% skin exposure after 60 seconds at 23°C and 50% relative humidity was measured. The test strip had dimensions of approximately 150 x 19 x 1.6 mm and was produced as follows: 23 g of the polymer was mixed with 0.1% by weight of an anti-oxidant ("Topanol" CA), and the mixture was introduced into a Brabender softener at 190°C, 30 revolutions per minute

and under a load of 10 kg to transform it into a crab. The crepe was placed in a draft tray, between aluminum foil, and pressed using an electric Tangye press at a temperature of 250°C. The press sample was preheated for a period of 6 minutes under just sufficient pressure to cause the polymer to flow over the draw board, i.e. an applied force of approx. 1 ton. After the pre-heating period, the applied power was raised to 15 tonnes in 5 tonne increments, degassing (i.e. release of pressure) took place

in steps of 5 tonnes. After 2 minutes at 15 tonnes, the press was cooled using air and water for 10 minutes until room temperature was reached. The plate obtained was then cut into strips with dimensions 150 x 19 x 1.6 mm. Strips in duplicate of each polymer were placed in a curing oven at 130°C, and after 2 hours at this temperature the heat was turned off, and the oven was cooled to ambient temperature at a rate of 15°c per hour.

The flexural modulus is dependent on the melt index of the polymer and increases by 0.18 GN/m when the melt index is increased by a factor

of 10, e.g. from melt index 3 to melt index 30. By using this ratio, it is calculated that at melt index 20 the flexural modulus of the polymer will be 1.43GN/m^.

EXAMPLES 82 TO 84

The procedure according to examples 78 to 80 was repeated at 70°C using the milled products from example 1/20

and 23 and a polymerization time of 4 hours. The results are reproduced in table 6.

Footnotes to Table 6

(a) , (c) and (d) - See Table 2.

EXAMPLE 85

The grinding process according to Example 1 was repeated using 6.54 grams of diphenylsulfone (17.6 molar percent in relation to TiCl3 which was then added) and 33.6 grams of titanium trichloride of Stauffer-AA quality. Oxygen gas was finally added to the mill instead of titanium tetrachloride. The amount of oxygen used was 120 ml at room temperature and pressure (corresponding to 2.94 molar percent in relation to the titanium trichloride). The oxygen gas was added from an injection syringe with a plunger sealed with liquid paraffin.

The ground titanium trichloride product was used to polymerize propylene using the process of Examples 50 to 74. Polypropylene was obtained in a yield of 26.0 g/mmol titanium trichloride, and the amount of diluent-soluble polymer was 0.94 wt. %.

EXAMPLES 86 TO 88

■ . — - • The grinding process of Example 1 was repeated, except that the titanium tetrachloride was replaced by different amounts of carbon tetrachloride, grinding was carried out for 24 hours and the final grinding in the presence of inert diluent was carried out for only two minutes.

The milled products were used to polymerize propylene using the process of Examples 26 to 49.

The results obtained are shown in table 7.

Footnotes to Table 7

(c) and (d) are as indicated in the footnotes to Table 2.

EXAMPLE 89

Two grindings were carried out - using the method described in example 1. The amounts of Stauffer-AA used in the paints were 32.7 and 39.9 respectively. The amount of diphenylsulfone was 20% molar amount relative to TiCl 3 , and the amount of titanium tetrachloride was 10% molar amount relative to TiCl 3 . Both grindings were carried out for 24 hours, the inert diluent was added, and grinding in the presence of the diluent was carried out for 2 minutes.

The suspensions of titanium trichloride material obtained from the

two paintings were combined. Analysis of the material showed a titanium/aluminium atomic ratio of 3.55:1.

EXAMPLE 90

A sample amount of the combined suspensions from example 89 containing approx. 200 mmol of TiCl-^ was transferred to an argon purge vessel with a glass-sinter bottom and provided with a stirrer. The vessel was immersed in an oil bath at room temperature. The liquid was filtered off, and the solid was resuspended in sodium-dried, degassed toluene. The oil bath was heated to 100°C. After 30 minutes at 100°C, the toluene. filtered out.

The solid was then treated with toluene twice more in the manner described above. The oil bath was then cooled to room temperature and the solid was treated twice with 100 ml portions of dry, degassed heptane as described for the treatment with toluene. The solid was then suspended in 500 ml of heptane. Analysis of the washed product showed a titanium/aluminum atomic ratio of 5.28:1.

EXAMPLES 91 and 92

The polymerization process of Examples 82 to 84 was repeated using the titanium trichloride products of Examples 89 and 90. The results obtained are set forth in Table 8.

Footnotes to table 8

(c) and (d) are as indicated in the footnotes to Table 2.

(g) TiCl3-89 is the combined product of Example 89, and TiCl3-90 is the washed material from Example 90.

(h) the melt index was measured by ASTMTest Method D 1238-70,

at 190°C and 10 kg.

EXAMPLE 9 3

Propylene was polymerized in the gas phase during use

of the titanium trichloride product from Example 90.

Into an 8 liter stainless steel autoclave equipped

with a water-cooling jacket and provided with an anchor-shaped stirrer, 800 grams of polypropylene powder with a melting index of 20 and with a bending modulus of approx. 1.4 GN/m2. The autoclave was heated to 70°C, evacuated and propylene gas was added to give a pressure of 1.36

ato. The autoclave was evacuated and propylene gas was added a total of six times over a period of 20 minutes.

Excess propylene pressure was released, the stirrer was started, and 24 millimoles of diethylaluminum chloride as a 1.0 M solution in heptane was added. After three minutes, 1 millimol of tributylamine as a 0.5 M solution in heptane was added. After further-

Over 7 minutes, 2 millimoles of the titanium trichloride product from Example 90 were added as a 0.384 M suspension in heptane. 10 minutes after the addition of the titanium trichloride, the autoclave was pressurized, step by step, to 27.2 ato with propylene. At pressures of 6.8, 13.6, 20.4 and 27.2 ato, 20 millimole portions of hydrogen were added. The pressure was maintained at 27.2 ato by the addition of propylene, and the temperature was maintained at 70°C. 10 millimoles of hydrogen were added after the addition of every 200 ml of propylene, the propylene being added by distillation of liquid propylene. 4 hours after the pressure of 27.2 ato was reached, the autoclave was vented and the polymer product was removed.

The overall product (including the 800 g of polypropylene originally present) had a melt index of 18.7, a flexural modulus of o 1.39 GN/m 2 and a measured titanium content of o 55 dpm by weight. Taking into account the titanium content of the original 800 grams of polypropylene, it was calculated that the polypropylene formed during the polymerization contained 62 ppm, by weight, of titanium residues from the catalyst.

EXAMPLE 94.

The procedure of Example 1 was repeated, except that 31.6 grams of Stauffer-AA were used (and 20 molar percent diphenyl sulfone and 10 molar percent titanium tetrachloride), and water at a temperature of 5°C was sprayed onto the mill. During the painting, the temperature rose from 5°C. Grinding was finished after 24 hours when the temperature had reached 15°C. The grinding step in the presence of inert hydrocarbon diluent was carried out in a time of only 2 minutes.

EXAMPLE 95

A sample amount of the ground product from Example 94 was washed with hot toluene using the method from Example 90. After cooling to room temperature, the solid was treated with and finally suspended in an inert hydrocarbon diluent with a boiling range of approx. 170 to 180°C, instead of the heptane used in Example 90.

EXAMPLE 96

A further sample of the ground product from Example 94 was heated to a temperature of 120°C and held at this temperature with gentle stirring for 2 hours under an atmosphere of argon. The system got then cooled to ambient temperature, and the entire mixture was then transferred to a storage vessel.

EXAMPLE 97

A further sample of the milled product from Example 94 was washed as described in Example 90, with the exception that a temperature of 120°C was used instead of 100°C, and at all stages, both at 120°C and at the subsequent treatment at ambient temperature, the liquid medium used was an inert hydrocarbon diluent with a boiling range of approx. 170 to 180°C.

EXAMPLE 98

A complex of titanium tetrachloride and diphenylsulfone was

produced in the following manner.

Into a nitrogen-containing 1 liter flask equipped with a thermometer and stirrer, 250 ml of sodium-dried toluene and 87.2 g (0.4 mol) of diphenylsulfone were introduced. The flask was evacuated to vacuum (0.2 mm Hg) and repressurized with nitrogen to atmospheric pressure. This procedure with evacuation and new pressure build-up was repeated a further four times.

The flask was then heated to 60°C and the diphenyl sulfone was dissolved to give a clear, colorless solution. 100 mL (0.92 mol) of titanium tetrachloride was added from a dropping funnel over a period of 2 minutes. The temperature of the contents of the flask rose to 80°C, and a yellow crystalline solid precipitated from a reddish solution. The mixture was cooled to 10°C with stirring and then filtered. The solid was washed six times with sodium-dried heptane (100 mL each time) and then dried under vacuum (0.2 mm Hg) at ambient temperature. A free-flowing yellow solid was obtained which, on analysis, proved to be Ph2S022TiCl4 (pH = phenyl). '

Into a ball mill equipped with stainless steel balls as described in example 1, 27.2 g of Stauffer-AA, 4.09 g of the titanium tetrachloride-diphenyl sulfone complex and 4.48 g of diphenyl sulfone were introduced in turn. The grinding process according to example 1 was repeated, except that the grinding was carried out for 24 hours, and water at a temperature of 20 to 26°C was sprayed onto the mill. After addition of the inert hydrocarbon diluent, milling was continued in the presence of the diluent for only 2 minutes.

EXAMPLES 99 TO 103 '

The polymerization process according to Examples 82 to 84 was repeated using the milled products from Examples 94 to 98. The results obtained are reproduced in Table 9.

Footnotes to Table 9.

(c) and (d) are as indicated in the footnotes to Table 2.

(i) The number refers to the example describing grinding of the Ticl^ component.

EXAMPLES 104 TO 115

Diphenysulfone was introduced into a ball mill equipped with stainless steel balls as described in Example 1. The mill was then evacuated to 0.2 mm Hg and purged with nitrogen. Into the mill was introduced 20 grams of titanium trichloride, the mill was placed on rollers, and titanium tetrachloride (when used) was added from an injection syringe over a period of 1 minute. The titanium trichloride used was either the product obtained by reducing titanium tetrachloride with hydrogen gas (Stauffer-TiCl^-H) or/by reducing titanium tetrachloride with titanium metal (Toho Titanium

.TiCl3-T).

The mill was then rotated at 120 rpm. minute

for 64 hours while water with a temperature of 20°C was sprayed over the mill. At the end of this period, 100 ml of an inert hydrocarbon diluent with a boiling range of approx. 170 to 180°C, added and the mill rotated for an additional 15 minutes. The mill contents were removed under nitrogen and diluted with a further amount of the same hydrocarbon diluent to approx. 0.3 M titanium trichloride per liter of suspension. The concentration of trivalent titanium in the suspension was determined by titration with cerium(IV) sulphate in sulfuric acid.

Further details from the grinding processes are set out in Table 10 together with comparative examples where the diphenylsulfone was omitted.

Footnotes to table 10

DPS is as stated in footnote (a) to table 1.

(j) H is Stauffer TiCl3-H

T is Toho Titanium TiCl^-T.

EXAMPLES 116 TO 127

The polymerization process of Examples 26 to 49 was repeated using the products of Examples 104 to 115. The results obtained, together with those obtained using the comparative products K to N, are set forth in Table 11.

Footnotes to table 11

(c) and (d) are as indicated in the footnotes to Table 2.

(k) The number or letter refers to the example or comparative example describing grinding of the TiCl^ component.

EXAMPLES 128 TO 139

The polymerization process from Examples 82 to 84 was repeated using the products from Examples 104 to 115, with the exception that 2 mmol of tri(n-butyl)amine was used. The results obtained, together with those obtained using the comparative products K to N, are set forth in Table 12.

Footnotes to table 12

(c) and (d) are as indicated in the footnotes to Table 2.

(k) is as indicated in the footnotes to Table 11.

J

Claims (25)

1. Process for treating a transition metal compound, in which a solid compound of a transition metal from groups IVA to VIA in the periodic table is ground together with at least one sulfur-containing organic compound. characterized in that a sulphur-containing organic compound is used selected from sulphon compounds with the formula sulphonamide compounds with the formula sulfide compounds with the formula where X or each X independently is a halogen atom, an alkyl, aryl, alkoxy, aryloxy, alkylthio or arylthio group, or a group -NRR', or two groups X can together form a saturated or unsaturated hydrocarbon ring; Y or each Y is independently a halogen atom, an alkyl, aryl, alkoxy, aryloxy, alkylthio or arylthio group or a group -N RR', or two groups Y can together form a saturated or unsaturated hydrocarbon ring; or a group X and a group Y can be replaced by a bond between the two phenyl groups which are bound to the -S O^ -group, the bond being either direct or through a group -O-, -CH2 -, -NR-, -S - or -C0-; Z or each Z is independently a halogen atom, an alkyl, aryl, alkoxy, aryloxy, alkylthio or arylthio group or a group -NRR', or two groups Z can together form a saturated or unsaturated hydrocarbon ring; D or each D is independently a halogen atom, an alkyl, aryl, alkoxy, aryloxy, alkylthio or arylthio group or a group -NRR'; T is -S-, -O-, -NR'- or -CO-;. R is a hydrogen atom or a hydrocarbyl group; R' is a hydrocarbyl group; R" is a hydrocarbyl group or group in n, m, p and q are each independently an integer from 0 to 5; and x is a positive integer. 2. ■ Method as stated in claim 1, characterized in that a sulfone which is diphenylsulfone is used as a sulfur-containing organic compound; 4-(phenylthio)-diphenylsulfone; 4-(phenoxy)diphenylsulfone; 2,4'-(diphenoxy)diphenylsulfone; 4,4'-(diphenoxy)diphenylsulfone; 4,4'-dichlorodiphenyl sulfone; 4,4'-(dimethyl)-diphenyl sulfone; 2,4,4'-(trimethyl)diphenyl sulfone; 6-phenylsulfonyl-tetralin; dibenzothiophene-5,5-dioxide; phenoxathiine-1Q,10-dioxide; thioxanthene-10,10-dioxide or 10-methylphenothiazine-5,5-dioxide. 3. Method as stated in claim 1, characterized in that a sulphonamide which is N,N-dimethylbenzenesulphonamide is used as a sulphurous organic compound; N,N-diethyl-benzenesulfonamide; N,N-diphenyl-benzenesulfonamide; N-methyl-N-phenyl-4-bromobenzenesulfonamide; N-methyl-N-phenyl-4-chlorobenzenesulfonamide; N,N-diethyl-4-phenoxybenzenesulfonamide or N,N-dibenzenesulfonyl-N,N'-dimethyl-1,2-diaminoethane.. 4. Method as stated in claim 1, characterized in that a sulphide such as erfenoxatiin, thianthrene or N-methylphenothiazine is used as a sulphur-containing organic compound. 5. Method as stated in one of the claims 1 to 4, characterized in that the grinding is carried out using a molar excess of the solid compound of a transition metal in relation to the organosulfur compound, preferably using from 5 to 100 molar percent, in relation to the solid compound of a transition metal, of the organo-sulfur bond. 6. Method as stated in one of claims 1 to 5, characterized in that the grinding is carried out in the presence of a Lewis acid compound, e.g. aluminum chloride or titanium tetrachloride, which is different from the solid compound of a transition metal. 7. Method as stated in claim 6, characterized in that an amount of Lewis acid compound is used in the range from 1 to 50%, preferably from 5 to 40% molar amount in relation to the amount of solid transition metal compound.:. 8. Method as stated in one of claims 1 to 5, characterized in that the grinding is carried out in the presence of an oxidizing agent such as oxygen gas, chlorine gas, carbon tetrachloride, hexachlorocyclopentadiene, tin (IV) chloride, phosphorus pentachloride or iodine. 9. Method as stated in claim 8, characterized in that the oxidizing agent is used, in an amount from 0.2 to 50%, preferably from 1 to 30% molar amount in relation to the amount of solid transition metal compound. 10. Method as stated in one of claims 1 or 5 to 9, characterized in that 4,4'-(dimethyl)-diphenylsulfone is used as organosulfur compound; diphenyl sulfone; N,N-diethyl-4-phenoxybenzenesulfonamide; N,N-diphenyl-benzenesulfonamide; phenoxathiine, phenoxathiine-10,10-dioxide or thioxanthene-10,10-dioxide. 11. Method as stated in one of claims 1 to 10, characterized in that the grinding is carried out using a ball mill, and the main part of the grinding is carried out in the absence of added solvents or suspending agents. 12. Method as stated in claim 11, characterized in that as a final step, an inert, organic liquid is added to the mixture being ground, and grinding is continued for a period of no more than 30 minutes. 13. Method as set forth in one of claims 1 to 12, characterized in that after painting, the painted material is heated to a temperature in the range from 60 to 200°C. 14. Method as stated in claim 13, characterized in that the ground material is washed with an inert, organic liquid at a temperature in the range from 60 to 200°C. 15. Olefin polymerization catalyst, characterized in that it contains 1) a transition metal compound; and 2) at least one organometallic compound of aluminum or of a non-transition metal from group II A in the periodic table or a complex of an organometallic compound of a non-transition metal from group IA or IIA in the periodic table and an organo-aluminum compound, characterized in that the transition metal compound is obtained by the method according to one of claims 1 to 14, 16. Catalyst as stated in claim 15, characterized • in that it comprises a further component :3) which is at least one organo-Lewis base compound, preferably a secondary or tertiary amine, a diamine or a compound containing both phosphorus and nitrogen atoms. 17. Catalyst as stated in claim 15 or 16, characterized in that it contains a further component 4) which is a substituted or unsubstituted polyene. 18. Catalyst as stated in one of claims 15 to 17, characterized in that for each molecular part of the solid transition metal compound that is present as component (1) (A), at least 0.05, preferably 1.0, molecular parts of component 2). 19. Catalyst as stated in claim 18, characterized in that up to 50 and preferably no more than 25 molecular parts of component 2) are present. 20. Catalyst as stated in one of claims 16 to 19, characterized in that for each molecular part of the solid transition metal compound present as component (1)(A), there is present from 0.01 to 10, preferably from 0.05 to 5.0, molecular parts of component 3), and the amount of component 3) is less than the amount of component 2). 21. Catalyst as stated in one of claims 17 to 20, characterized in that for each molecular part of component 2). is present from 0.01 to 1.0, preferably from 0.05 to 0.5, molecular parts of component 4). 22. Catalyst as specified in one of claims 16, 17, 20 and 21, characterized in that component 3) is hexamethylphosphoric acid triamide; 2-Dimethylamino-1,3-dimethyl-1,3,2-diaza-phospholidin-2-oxide, N,N,N',N',N"-pentamethyl-N"-/3-dimethylaminoethyl^ phosphoric acid triamide ; tetramethylethylenediamine or tributylamine. 23. Process for producing a polymer or copolymer of an olefin monomer, in which an olefin monomer is brought into contact with a polymerization catalyst, characterized in that the polymerization catalyst is one that is described in one of claims 15 to 22. 24. Method as stated in claim 23, characterized in that the monomers and any diluents are of commercial purity and are subjected to further purification. r- 25. Method as stated in claim 23 or 24, characterized in that propylene is polymerized to give a polymer with a flexural modulus of at least 1.00 GN/m 2 , and the polymerization is continued until the polymer contains no more than 100 parts per million by weight, of transition metal derived from catalyst residues in the polymer.