Title of Invention	"PREPARATION OF OLEFIN POLYMERISATION CATALYST COMPONENT."
Abstract	A process for producing an olefin polymerisation catalyst component in the form of solidified particles having a predetermined size range of 5 to 200 urn, comprising: preparing a solution of a complex of a Gp 2 metal and an electron donor by reacting a compound of said Gp 2 metal with said electron donor or a precursor thereof in an organic liquid reaction medium, reacting said complex obtained in the previous step, in solution, with at least one compound of a transition metal to produce an emulsion having a dispersed phase in the form droplets, wherein the dispersed phase contains more than 50 mol% of the Gp 2 metal in said complex; maintaining the droplets of said dispersed phase within the average size range 5 to 200 µm by agitation in the presence of an emulsion stabilizer and solidifying said droplets to obtain solidified particles; and recovering, washing and drying said particles to obtain said catalyst component.

Title of Invention

"PREPARATION OF OLEFIN POLYMERISATION CATALYST COMPONENT."

Abstract

A process for producing an olefin polymerisation catalyst component in the form of solidified particles having a predetermined size range of 5 to 200 urn, comprising: preparing a solution of a complex of a Gp 2 metal and an electron donor by reacting a compound of said Gp 2 metal with said electron donor or a precursor thereof in an organic liquid reaction medium, reacting said complex obtained in the previous step, in solution, with at least one compound of a transition metal to produce an emulsion having a dispersed phase in the form droplets, wherein the dispersed phase contains more than 50 mol% of the Gp 2 metal in said complex; maintaining the droplets of said dispersed phase within the average size range 5 to 200 µm by agitation in the presence of an emulsion stabilizer and solidifying said droplets to obtain solidified particles; and recovering, washing and drying said particles to obtain said catalyst component.

Full Text	PREPARATION OF OLEFIN POLYMERISATION CATALYST COMPONENT This invention relates to a process for the preparation of a particulate olefin polymerisation catalyst component, particularly one comprising a Gp 2 metal of the Periodic Table (IUPAC, Nomenclature of Inorganic Chemistry, 1989.), a compound of a transition metal and an electron donor. The invention also relates to the use of such a catalyst component in the polymerisation of olefins. Background of the invention Processes for the preparation of such a catalyst component -as described, for instance, in WO 00/08073 and 00/08074 -usually include a step in which a magnesium-Gp 4 metal-electron donor component is recovered by precipitation from solution, typically by contacting the solution with a large amount of an aliphatic hydrocarbon. However, such precipitation leads to a tar-like reaction product of low catalytic activity, that needs to be washed several times in order to decrease the amount of inactive Gp IVB metal complex. Aromatic hydrocarbons have also been used for the precipitation, but they lead to a very finely divided precipitate which is difficult to deposit. Worse still, it is difficult to carry out such precipitation in a controlled and reproducible manner, leading to unsatisfactory product morphology. Moreover variable and low concentrations of catalyst constituents such as butyl chloride may result, as a consequence of precipitation evaporative removal of aliphatic solvent. Description of the invention We have devised a new technique for recovering such a component from solution, which avoids the unsatisfactory precipitation previously practised and leads to an improved product morphology and consistent product composition. According to the present invention a process for producing an olefin polymerisation catalyst component in the form of particles having a predetermined size range, comprises preparing a solution of a complex of a Gp 2 metal and an electron donor by reacting a compound of said metal with said electron donor or a precursor thereof in an organic liquid reaction medium; reacting said complex, -in solution, with a compound of a transition metal to produce an emulsion the dispersed phase of which contains more than 50 mol% of the Gp 2 metal in said complex; maintaining the particles of said dispersed phase within the average size range 5 to 200 µm by agitation in the presence of an emulsion stabilizer and solidifying said particles; and recovering, washing and drying said particles to obtain said catalyst component. The compound of a transition metal is preferably a compound of a Group 4 metal. The Group 4 metal is preferably titanium, and its compound to be reacted with the complex of a Gp 2 is preferably a halide. In a further embodiment of the invention a compound of a transition metal used in the process can also contain organic ligands typically used in the field known as a single site catalyst. In a still further embodiment of the invention a compound of a transition metal can also be selected from Group 5 metals, Group 6 metals, Cu, Fe, Co, Ni and/or Pd. The complex of the Group 2 metal is preferably a magnesium complex. The invention will henceforth be described in relation to a preferred embodiment of the process, namely to a process for the preparation of a Ziegler-Natta type catalyst. A preferred embodiment of the invention is a process for producling catalysts of the Ziegler-Natta type, in the form of particles having a predetermined size range, comprising: preparing a solution of magnesium complex by reacting an alkoxy magnesium compound and an electron donor or precursor thereof in a C6-C10 aromatic liquid reaction redium; reacting said magnesium complex with a compound of at least one IV valent Gp 4 metal at a temperature greater than 100C and less than 60°C, to produce an emulsion of a denser, TlCl4/toluene-insoluble, oil dispersed phase having, Gp 4 metal/Mg mol ratio 0.1 to 10 in an oil disperse phase having Gp 4 metal/Mg mol ratio 10 to 100; maintaining the droplets of said dispersed phase within the size range 5 to 200 µm by agitation in the presence of an emulsion stabilizer while heating the emulsion to solidify said droplets; and recovering, washing and drying the solidified particles to obtain said catalyst component. The said disperse and dispersed phases are thus distinguishable from one another by the fact that the denser oil, if contacted with a solution of titanium tetrachloride in toluene, will not dissolve in it. A suitable solution for establishing this criterion would be one having a toluene mol ratio of 0.1 to 0.3. They are also distinguishable by the fact that the great preponderance of the Mg provided (as complex) for the reaction with the Gp 4 metal compound is present in the dispersed phase, as revealed by comparison of the respective Gp 4 metal/Mg mol ratios. In effect, therefore, virtually the entirety cf the reaction product of the Mg complex with the Gp 4 metal - which is the precursor of the ultimate catalyst component - becomes the dispersed phase, and proceeds through the further processing steps to final dry particulate form. The disperse phase/ still containing a useful quantity of Gp 4 metal, car. be reprocessed for recovery of that metal. The production of a two-phase, rather than single-phase (as in prior practice) reaction product is encouraged by carrying out the Mg complex/Gp 4 metal compound reaction at low temperature, specifically above 10°C but below 60°C, preferably between above 20°C and below 50°C. Since the two phases will naturally tend to separate into a lower, denser phase and supernatant lighter phase, it is recessary to maintain the reaction product as an emulsion by agitation in the presence of an emulsion stabiliser. The resulting particles of the dispersed phase of the emulsion are of a size, shape (spherical) and uniformity which render the ultimate catalyst component extremely effective in olefin polymerisation. This morphology is preserved during the heating to solidify the particles, and of course throughout the final washing and. drying steps. It is, by contrast, difficult to the point of impossibility to achieve such morphology through precipitation, because of the fundamental uncontrollability of nucleation and growth, and the large number of variables, which affect these events. The electron donor is preferably an aromatic carboxylic acid ester, a particularly favoured ester being dioctyl phthalate. The donor may conveniently be formed in situ by reaction of an aromatic carboxylic acid chloride precursor with a C2-C16 alkanol and/or diol. The liquid reaction medium preferably comprises toluene. Furthermore, emulsifying agents/emulsion stabilisers can be used additionally in a manner known in the art for facilitating the formation and/or stability of the emulsion. For the said purposes e.g. surfactants, e.g. a class based on acrylic or methacrylic polymers can be used. Preferably, said emulsion stabilizers are acrylic or methacrylic polymers, in particular those with medium sized ester side chains having more than 10, preferably more than 12 carbon atoms and preferably less than 30, and preferably 12 to 20 carbon atoms in the ester side chain. Particular preferred are unbranched C12 to C20 acrylates such as poly (hexadecyl)-methacrylate and poly(octadecyl)-methacrylate. It has been found that the best results are obtained when the Gp 4 metal/Mg mol ratio of the denser oil is 1 to 5, preferably 2 to 4, and that of the disperse phase oil is 55 to 65. Generally the ratio of the mol ratio Gp 4 metal/Mg in the disperse phase oil to that in the denser oil is at least 10. Solidification of the dispersed phase particles by heating is suitably carried out at a temperature of 70-150°C, usually at 90-110°C. Preparation of the magnesium corplex may be carried out over a wide range of temperatures, 20 to 80°C being preferred, 50 to 70°C most preferred. The finally obtained catalyst component is desirably in the form of particles having an average size range of 10 to 200 um, preferably 20 to 50 um. The present invention further comprehends an olefin polymerisation catalyst comprising a catalyst component prepared as aforesaid, in association with an alkyl aluminium cocatalyst, and optionally with external donors, and the use of that polymerisation catalyst for the polymerisation of C2 to C10-olefins. The reagents can be added to the reaction medium in any order. However it is preferred that in a first step the alkoxy magnesium compound is reacted with a carboxylic acid halide precursor of the electron donor to form an intermediate; and in a second step the obtained product is further reacted with the Gp 4 metal. The magnesium compound preferably contains from 1 to 20 carbon atoms per alkoxy group, and the carboxylic acid should contain at least 8 carbon atoms. Reaction of the magnesium compound, carboxylic acid halide and polyhydric alcohol proceeds satisfactorily at temperatures in the range 20 to 80°C, preferably 50 to 70°C. The product of that reaction, the "Mg complex", is however reacted with the Gp 4 metal compound at a lower temperature, contrary to previous practice, to bring about the formation of a two-phase, oil-in-oil, product. Use of the aromatic medium for preparation of the Mg complex contributes to consistent product morphology and higher bulk density. Catalyst bulk density and morphology correlate with product bulk density and morphology the so-called "replication effect". The technique adopted in the novel regimen of the invention is inherently more precise than that formerly employed, and thus further contributes to product consistency, as well as sharply reducing the volumes of solvent to be handled and thus improving process economics. The reaction medium used as solvent can be aromatic or a mixture of aromatic and aliphatic hydrocarbons, the latter one containing preferably 5-9 carbon atoms, more preferably 5 -7 carbon atoms, or mixtures thereof. Preferably, the liquid reaction medium used as solvent in the reaction is aromatic and is more preferably selected from hydrocarbons such as substituted and unsubstituted benzenes, preferably from alkylated benzenes, even more preferably from toluene and the xylenes, and is most preferably toluene. The molar ratio of said aromatic medium to magnesium is preferably less than 10, for instance from 4 to 10, preferably from 5 to 9. The recovered particulate product is washed at least once, preferably at least twice, most preferably at least three times with a hydrocarbon, which preferably is selected from aromatic and aliphatic hydrocarbons, preferably with toluene, particularly with hot (e.g. 90°C) toluene. A further wash is advantageously performed with heptane, most preferably with hot (e.g. 90°C) heptane, and yet a further wash with pentane. A washing step typically includes several substeps. A favoured washing sequence is, for example, one wash with toluene at 90°C, two washes with heptane at 90°C and one or two washes with pentane at room temperature. The washing can be optimized to give a catalyst with novel and desirable properties. Finally, the washed catalyst component is dried, as by evaporation or flushing with nitrogen. It is preferable that the intermediates as well as the final product of the process be distinct compounds with an essentially stoichiometric composition. Often, they are complexes. A complex is, according to Rompps Chemie-Lexicon, 1. Edition, Franckh'sche Verlagshandlung, W. Keller & Co., Stuttgart, 1973, page 1831, "a derived name of compounds of higher order, which originate from the combination of molecules, - unlike compounds of first order, in the creation of which atoms participate". The alkoxy magnesium compound group is preferably selected from the group consisting of magnesium dialkoxides, complexes of a magnesium dihalide and an alcohol, and complexes of a magnesium dihalide and a magnesium dialkoxide. It may be a reaction product of an alcohol and a magnesium compound selected from the group consisting of dialkyl magnesiums, alkyl magnesium alkoxides, alkyl magnesium halides and magnesium dihalides. It can further be selected from the group consisting of dialkyloxy magnesiums, diaryloxy magnesiums, alkyloxy magnesium halides, aryloxy magnesium halides, alkyl magnesium alkoxides, aryl magnesium alkoxides and alkyl magnesium aryloxides. The magnesium dialkoxide may be the reaction product of a magnesium dihalide such as magnesium dichloride or a dialkyl magnesium of the formula R2Mg, wherein each one of the two Rs is a similar or different C1-C2o alkyl, preferably a similar or different C4-C10 alkyl. Typical magnesium alkyls are ethylbutyl magnesium, dibutyl magnesium, dipropyl magnesium, propylbutyl magnesium, dipentyl magnesium, butylpentylmagnesium, butyloctyl magnesium and dioctyl magnesium. Most preferably, one R of the formula R2Mg is a butyl group and the other R is an octyl group, i.e. the dialkyl magnesium compound is butyl octyl magnesium. Typical alkyl-alkoxy magnesium compounds RMgOR, when used, are ethyl magnesium butoxide, butyl magnesium pentoxide, octyl magnesium butoxide and octyl magnesium octoxide. Dialkyl magnesium, alkyl magnesium alkoxide or magnesium dihalide can react with a polyhydric alcohol R'(OH)m, or a mixture thereof with a monohydric alcohol R'OH. Typical C2 to C6 polyhydric alcohols may be straight-chain or branched and include ethylene glycol, propylene glycol, trimethylene glycol, 1,2-butylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, 2,3-butylene glycol, 1,5pentanediol, 1,6-hexanediol, 1,8-octanediol, pinacol, diethylene glycol, triethylene glycol, and triols such as glycerol, methylol propane and pentareythritol. The polyhydric alcohol can be selected on the basis of the activity and morphology it gives the catalyst component. The aromatic reaction medium may also contain a monohydric alcohol, which may be straight- or branched-chain. Typical C1 -C2o monohydric alcohols are methanol, ethanol, n-propanol, iso-propanol, n-butanol, iso-butanol, sec.biitanol, tert.butanol, n-amyl alcohol, iso-amyl alcohol, sec.amyl alcohol, tert.amyl alcohol, diethyl carbinol, akt. amyl alcohol, sec. isoamyl alcohol, tert.butyl carbinol. Typical C6-C10 monohydric alcohols are hexanol, 2-ethyl-lbutanol, 4-methyl-2-pentanol, 1-heptanol, 2-heptanol, 4-heptanol, 2,4-dimethyl-Spentanol, 1-octanol, 2-octanol, 2-ethyl-l-hexanol, 1-nonanol, 5-nonanol, diisobutyl carbinol, 1-decanol and 2,7-dimethyl-2-octanol. Typical >C10 monohydric alcohols are n-1-undecanol, n-1-dodecanol, n-1-tridecanol, n-1-tetradecanol, n-1-pentadecanol, 1 -hexadecanol, n-1-heptadecanol and n-1-octadecanol. The monohydric alcohols may be unsaturated, as long as they do not act as catalyst poisons. Preferable monohydric alcohols are those of formula R'OH in which R1 is a C2-C6 alkyl group, most preferably a C4-C12 alkyl group, particularly 2-ethyl-l-hexanol. Preferably, essentially all of the aromatic carboxylic acid ester is a reaction product of a carboxylic acid halide, preferably a dicarboxylic acid dihalide, more preferably an unsaturated α,β-dicarboxylic acid dihalide, most preferably phthalic acid dichloride, with the monohydric alcohol. The compound of a four-valent Gp 4 metal compound containing a halogen is preferably a titanium tetrahalide. Equivalent to titanium tetrahalide is the combination of an alkoxy titanium halide and a halogenation agent therefore, which are able to form a titanium tetrahalide in situ. The most preferred halide is the chloride, for zirconium and hafnium as well as for titanium. The reaction conditions used in the claimed process may be varied according to the used reactants and agents. As is known, the addition of at least one halogenated hydrocarbon during the process can lead to further improved catalytic activity. Reactive halogenated hydrocarbons preferably have the formula R'"X'"n wherein R'" is an n-valent C1-C2o hydrocarbyl group, particularly a C1-C10 paraffin, X'" is a halogen and n is an integer from 1 to 4. Such chlorinated hydrocarbons include monochloromethane, dichloromethane, trichloromethane (chloroform), tetrachloromethane, monochloroethane, (1,1)-dichloroethane, (1,2)-dichloroethane, (1,1,1)-trichloroethane, (1,1,2)-trichloroethane, (1,1,1,2}-tetrachloroethane, (1,1,2,2) tetrachloroethane, pentachloroethane, hexachloroethane, (1)-chloropropane, (2)-chloropropane, (1,2)-dichloropropane, (l,3)-dichloropropane, (1,2,3)trichloropropane, (1)-chlorobutane, (2)-chlorobutane, isobutyl chloride, tert.butyl chloride, (1,4)-dichlorobutane, (1)-chloropentane, (1,5)-dichloropentane. The chlorinated hydrocarbons may also be unsaturated, provided that the unsaturation does not act as catalyst poison in the final catalyst component. In the above formula, R1" is preferably a mono-or bivalent C1-C10 alkyl group , independently, X'" is preferably chlorine and, independently, n is preferably 1 or 2. Preferred compounds include butyl chloride (BuCl), dichloroalkanes such as (l/4-) dichlorobutane, and tertiary butyl chloride. Though the catalyst preparation according to the inventive method can be carried out batchwise, it is also preferable and possible to prepare the catalyst component semi-continuously our continuously. In such semi-continuous or continuous process, the solution of the complex of the Group 2 metal and said electron donor, which is prepared by reacting the compound of said metal with said electron donor in an organic liquid reaction medium, is mixed with at least one compound of a transition metal, which might be solved in the same or different organic liquid reaction medium. The so obtained solution is then agitated, possibly in the presence of an emulsion stabilizer, and then the so-agitated emulsion is fed into a temperature gradient reactor, in which the emulsion is subjected a temperature gradient, thus leading to solidifying the droplets of a dispersed phase of the emulsion. When feeding said agitated emulsion to the temperature gradient reactor, an inert solvent, in which the droplets are not soluble, can additionally be fed into that gradient reactor in order to improve the droplet formation and thus leading to a uniform grain size of the particles of the catalyst component, which are formed in the temperature gradient reactor when passing through said line. Such additional solvent might be the same as the organic liquid reaction medium, which is used for preparing the solution of the complex of the Group 2 metal as explained above in more detail. The solidified particles of the olefin polymerisation catalyst component can subsequently be recovered by an in-stream filtering unit and then, optionally after some additional washing and drying steps in order to remove unreacted starting components, can be stored for further use. In one embodiment the catalyst can be fed after washing steps into the olefin polymerisation reactor, so that a continuous preparation and fed to the reactor is guaranteed. As it can be seen from the above description of the semi- continuous or continuous process, it is thus possible to use separated reaction vessels for the different process steps and to transfer the reaction products which are prepared in the respective reaction vessels and to fed them in-line into further reaction vessels for formation of the emulsion and, subsequently, of the solidified particles. It is one possibility to use a full-continuous process as the time saving in said process is remarkable. In such fully continuous process, the formation of the solidified particles could be carried out in the temperature gradient line in the kind of pipe reactor, which is sufficiently long and which is subjected said temperature gradient from the starting temperature in the lower range of 20 to 80°C up to a "solidifying"temperature of 70 to 150°C. The temperature gradient is preferably obtained by means of heating the pipe reactor from the outside by applying normal heaters, microwaves, etc. As mentioned before, a filtering unit might preferably be used for filtering the solidified particles from the solvent stream. For said filtering unit, various drums and sieving systems can be used, depending on the specific particle sizes. STATEMENT OF INVENTION In accordance with the present invention, it relates to a process for producing an olefin polymerisation catalyst component in the form of solidified particles, comprising; preparing a solution of a complex of a Gp 2 metal and an electron donor by reacting a compound of said Gp 2 metal with said electron donor or a precursor thereof in an organic liquid reaction medium, reacting said complex obtained in the previous step, in solution, with at least one compound of a transition metal to produce an emulsion having a dispersed phase in the form droplets, wherein the dispersed phase contains more than 50 mol% of the Gp 2 metal in said complex; maintaining the droplets of said dispersed phase within the average size range 5 to 200 µm by agitation in the presence of an emulsion stabilizer and solidifying said droplets to obtain solidified particles; and recovering, washing and drying said particles to obtain said catalyst component. In accordance with the present invention, it relates to an olefin polymerisation catalyst component such as herein described. Some preferred embodiments of the invention are described, by way of illustration, in the following Examples. EXAMPLE 1 A magnesium complex solution was prepared by slowly adding over a 40 minute period, with stirring, 110 ml of a 20% solution in toluene of BOMAG-A (Tradename) [Mg(Bu)1.5 (Oct)0.5] to 38.9 ml of 2-ethylhexanol which had been cooled to 5°C in a 300 ml glass reactor. During the addition the reactor contents were maintained below 15°C. The temperature was then raised to 60°C and held at that level for 30 minutes with stirring, at which time reaction was complete, 6.4 ml phthaloyl chloride was then added over an 11 minute period. The reactor contents were stirred at 60°C for 20 minutes, 12.9 ml 1-chlorobutane was added, and stirring continued for another 15 minutes at 60°C. The resulting stable, yellowish Mg complex solution was cooled to room temperature. 19.5 ml TiCl4, 5 ml heptane and 28.7 of the above-prepared Mg complex solution were reacted at 25°C in a 300 ml glass reactor. After 5 minutes, reaction was complete and a dark red emulsion had formed. The temperature was raised to 50°C, 2 ml of Viscoplex 1-254 (Tradename) (40-44% of acrylic polymer in base oil) was added, and the reactor contents were stirred for 3.0 minutes. The resulting stabilized emulsion was then heated to 90°C, with stirring, for 10 minutes to solidify the particles forming the dispersed phase. After settling and syphoning the solids (2.6 grams) underwent washing with: 1. 100 ml toluene at 90°C for 30 minutes; 2. 60 ml heptane, at 90°C for 20 minutes; 3. 60 ml heptane, at 35°C for 10 minutes, 4. 60 ml pentane, at 30°C for 5 minutes; and 5. 60 ml pentane, at 30°C for 5 minutes. The solids were then dried at 60°C by nitrogen purge. The particles were established by microscopic examination to be perfectly spherical in shape. The Coulter PSD is shown in Figure -1. EXAMPLE 2 Example 1 was repeated, in order to evaluate the consistency of the procedure. The quantity of solids product was 2.6 g, the particles perfectly spherical. The Coulter PSD is shown in Figure 2. TABLE 1 (Table Removed 1) * Di-ethyl-hexyl phthalate (internal electron donor) ** Measured with Coulter LS200 at room temperature with n- heptane as medium EXAMPLES 3 and 4 The products of Examples 1 and 2 were evaluated as catalyst components in propylene polymerisation ir. the following manner. 0.9 ml triethyl aluminium (TEA) (co-catalyst), 0.12 ml cyclohexyl methyl dimethoxy silane (CMMS: as an external donor and 30 ml n-pentane were mixed and allowed to react for 5 minutes. Half of the mixture was then added to a polymerisation reactor and the other half was mixed with 20 mg of the components prepared in Examples 1 and 2. After an additional 5 minutes the component TEA/dcnor/n-pentane mixture was added to the reactor. The Al/Ti mole ratio of the resulting polymerisation catalyst was 250 mol/mol and the Al/CMMS mole ratio was 10 mol/mol. Propylene bulk polymerisation was carried out in a stirred 5 1 tank reactor. 7O mmol hydrogen and 1400 g propylene were introduced into the reactor and the temperature was raised within 15 minutes to the polymerisation temperature of 70°C. The polymerisation time at 70°C was 60 minutes, after which the polymer formed was taken out from the reactor. Example 3 employed the catalyst containing component of Example 1 and Example 4 that of Example 2. The results of the polymerisation evaluations are summarised in the following Table 2. TABLE 2 (Table Removed 2) ISO 1133, 2.16 kg load at 230°C xylene-soluble fraction of product at 25°C polymer-bulk density (ASTM D 1895} The polymer particles were spherical, with a markedly narrow size distribution: more than 75% of the product was of 0.5-1.00 mm particle diameter. Examples 5-8 In following examples poly(hexadecylmethacrylate)in different amounts (Examples 5-7) and poly(octadecylmethacrylate) (Example 8), both available from Aldrich, were used in stead of Viscoplex. Preparation of the soluble Mg-complexes Method A) In a 150 1 steel reactor 19,4 kg of 2-ethyl hexanol were added at 20 °C. 56,0 kg of a 20 % BOMAG A solution in toluene were then slowly added to the well stirred alcohol. The temperature of the mixture was then increased to 60 °C, and the reactants were allowed to react for 30 minutes at this temperature. After addition of 5,5 kg of 1,2-phthaloyl dichloride, the reaction mixture was stirred at 60 °C for another 30 minutes to ensure complete reaction. 13.8 kg of 1-chloro butane were then added at 60 °C, and stirring at -this temperature was continued for 30 minutes. After cooling to room temperature a yellow solution was obtained. Method B) In a 300 ml glass reactor 38,9 ml of 2-ethyl hexanol were added at 20 °C. 110,0 ml of a 20 % BOMAG A solution in toluene were then slowly added to the well stirred alcohol. The temperature of the mixture was then increased to 60 °C, and the reactants were allowed to react for 60 minutes at this temperature. After addition of 6,4 ml of 1,2-phthaloyl dichloride, the reaction mixture was stirred at 60°C for another 60 minutes to ensure complete reaction. After.cooling to room temperature a yellow solution was obtained. Example 5 Preparation of the catalyst component 19,5 ml titanium tetrachloride were placed in a 300 ml glass reactor equipped with a mechanical stirrer. After addition of 5,0 ml n-heptane, 31,0 g of the Mg-complex (method A) was added to the well-stirred reaction mixture at 25 °C. Mixing speed was kept constant 170 rpm through whole synthesis. After addition a dark red emulsion was formed. The temperature was increased to 50 °C and 0,9 ml poly(hexadecyl methacrylate)-toluene solution was added. After 30 min mixing, the temperature was increased to 90°C and then after 10 min the mixing was stopped and the catalyst was let to settle. After siphoning, the solid was washed with 100 ml of toluene at 90 °C for 30 min. Then the washings were continued with two times 60 ml heptane and twice with 60 ml pentane. The first heptane washing took 20 min at 90 °C and the second one 10 min. During the second heptane wash the temperature was decreased down to c. 25 °C. The pentane washing was then carried out for 5 min at c. 25°C. Finally the solid catalyst was dried at 60°C by purging nitrogen through the catalyst bed. Catalyst composition is shown in TABLE 3. The catalyst particle size distribution by Coulter is shown in Figure 3. Bulk polymerisation of propylene The propylene bulk polymerisation was carried out as in Example 3 but using the catalyst of example 5. Polymerisation results are disclosed in TABLE 4. Polymer particle size distribution by sieving is disclosed in TABLE 5. Example 6 The catalyst preparation and polymerisation were carried out as in the Example 5, except 0,45 ml poly(hexadecyl methacrylate)-toluene solution was used in catalyst preparation. Catalyst composition is disclosed in TABLE 3 and polymerisation results in TABLE 4 and polymer particle size distribution in TABLE 5. The catalyst particles were spherical and catalyst particle size distribution by Coulter is shown in Figure 4. Example 7 The catalyst preparation and polymerisation were carried out as in the Example 5, except 1,35 ml poly(hexadecyl methacrylate)-toluene solution was used in catalyst preparation. Catalyst composition is disclosed in TABLE 3 and polymerisation results in TABLE 4 and polymer particle size distribution in TABLE 5. The catalyst particles were spherical. The catalyst particle size distribution by Coulter is shown in Figure 5. Example 8 Example 8 was done as Example 5, but Mg complex (method B) was used and the poly(octadecyl methacrylate)-toluene solution was used instead of poly(hexadecyl methacrylate). The catalyst particles were spherical. Catalyst composition is disclosed in TABLE 3 and polymerisation results in TABLE 4 and polymer particle size distribution in TABLE 5. The catalyst particle size distribution by Coulter is shown in Figure 6. TABLE 3 - Catalyst composition (Table Removed 3) TABLE 4 - Polymerisation results (Table Removed 4) TABLE 5. Polymer particle size distribution by sieving. % Polymer on sieves (Table Removed 5) We claim: 1. The process for producing an olefin polymerisation catalyst component in the form of particles having a predetermined size range, comprising: preparing a solution of a complex of a Gp HA metal and an electron donor by reacting a compound of said metal with said electron donor or a precursor thereof in an organic liquid medium, wherein the preparation of the Gp IIA metal complex is carried out at a temperature of 20 to 80 °C; reacting said complex, in solution, with at least one compound of a transition metal, at a temperature of 10 to 60 °C, to produce an emulsion, wherein said emulsion is composed of a dispersed phase which is a TiCl4/toluene -insoluble oil having a Gp IVB metal/Mg mol ratio greater than 0.1 and less than 10 and a disperse phase which is an oil less dense than that of the dispersed phase and which has a Gp IVB metal/Mg mol ratio of 10 to 100, the dispersed phase of which contains more than 50 mol% of the Gp IIA metal; maintaining the particles of said dispersed phase within the average size range 10 to 200 urn by agitation in the presence of an emulsion stabilizer and solidifying said particles, wherein the solidification of said particles is effected by heating; and recovering, washing and drying said particles to obtain said catalyst component. 2. The process as claimed in claim 1, wherein said transition metal is Gp IVB metal. 3. The process as claimed in claim 1 or claim 2, wherein said Gp IIA metal is magnesium. 4. The process as claimed in any preceding claim, wherein said medium comprised a C6-C10 aromatic hydrocabron. 5. The process as claimed in claim 1, wherein the Gp IVB metal/Mg mol ratio of said disperse phase is 20 to 80, 6. The process as claimed in claim 1, wherein the Gp IVB metal/Mg mol ratio of said disperse phase is 45 to 75. 7. The process as claimed in any preceding claim, wherein said electron donor is an aromatic . carboxylic acid erter. 8. The process as claimed in any preceding claim, wherein said electron donor is dioctyl phthalate. 9. The process as claimed in any preceding claim, wherein said liquid reaction medium comprises toluene. 10. The process as claimed in any of claims 2 to 9, wherein said Gp IVB metal is titanium. 11. The process as claimed in any of claims 2 to 10, wherein said compound of a Gp IVB metal is halide, wherein the halide is chloride. 12. A process according to any of claims 3 to 11 wherein said magnesium complex and Gp IVB metal compound are reacted at a temperature of greater than 20 °C to less than 50 °C. 13. The process as claimed in any preceding claim, wherein said emulsion stabilizer is a surfactant. 14. The process as claimed in claim 13, wherein said surfactant comprises an acrylic or methacrylic polymer. 15. The process as claimed in any of claims 1 and 5 to 13, wherein the Gp IVB metal/Mg mol ratio of said denser oil is 2 to 4 and that of the disperse phase oil is 55 to 65. 16. The process as claimed in claim 15, wherein the ratio of the mol ratio Gp IV metal/Mg in the disperse phare oil to that in said denser oil is at least 10. 17. The process as claimed in any of claims 1 to 15, wherein the emulsion is heated to a temperature of 70-150 °C to solidify said particles. 18. The process as claimed in claim 17, wherein the temperature to which the emulsion is heated is 90-110 °C. 19. The process as claimed in claim 1, wherein the Gp HA metal is magnesium and the preparation of the magnesium complex is carried out at a temperature of 50 to 70 °C. 20. The process as claimed in claim 1, wherein said transition metal is a Gp VB metal and a Gp VIB metal. 21. The process as claimed in claim 1, wherein said transition metal is Cu, Fe, Co, Ni and Pd. 22. The process as claimed in any preceding claim wherein said obtained catalyst component is in the form of particles having an average size range of 10 to 200 urn. 23. A process as claimed in claim 22, wherein said particles have an average size range of 20 to 50 urn. 24. An olefin polymerisation catalyst component prepared according to the process as claimed in any one of the claims 1 to 23. 25. An olefin polymerisation catalyst component as claimed in the previous claims, whenever used for the polymerization of the C2 to C10 α-olefins.

Full Text

PREPARATION OF OLEFIN POLYMERISATION CATALYST COMPONENT
This invention relates to a process for the preparation of a particulate olefin polymerisation catalyst component, particularly one comprising a Gp 2 metal of the Periodic Table (IUPAC, Nomenclature of Inorganic Chemistry, 1989.), a compound of a transition metal and an electron donor. The invention also relates to the use of such a catalyst component in the polymerisation of olefins.
Background of the invention
Processes for the preparation of such a catalyst component -as described, for instance, in WO 00/08073 and 00/08074 -usually include a step in which a magnesium-Gp 4 metal-electron donor component is recovered by precipitation from solution, typically by contacting the solution with a large amount of an aliphatic hydrocarbon. However, such precipitation leads to a tar-like reaction product of low catalytic activity, that needs to be washed several times in order to decrease the amount of inactive Gp IVB metal complex. Aromatic hydrocarbons have also been used for the precipitation, but they lead to a very finely divided precipitate which is difficult to deposit. Worse still, it is difficult to carry out such precipitation in a controlled and reproducible manner, leading to unsatisfactory product morphology. Moreover variable and low concentrations of catalyst constituents such as butyl chloride may result, as a consequence of precipitation evaporative removal of aliphatic solvent.
Description of the invention
We have devised a new technique for recovering such a component from solution, which avoids the unsatisfactory precipitation previously practised and leads to an improved
product morphology and consistent product composition.
According to the present invention a process for producing an olefin polymerisation catalyst component in the form of particles having a predetermined size range, comprises preparing a solution of a complex of a Gp 2 metal and an electron donor by reacting a compound of said metal with said electron donor or a precursor thereof in an organic liquid reaction medium; reacting said complex, -in solution, with a compound of a transition metal to produce an emulsion the dispersed phase of which contains more than 50 mol% of the Gp 2 metal in said complex; maintaining the particles of said dispersed phase within the average size range 5 to 200 µm by agitation in the presence of an emulsion stabilizer and solidifying said particles; and recovering, washing and drying said particles to obtain said catalyst component.
The compound of a transition metal is preferably a compound of a Group 4 metal. The Group 4 metal is preferably titanium, and its compound to be reacted with the complex of a Gp 2 is preferably a halide. In a further embodiment of the invention a compound of a transition metal used in the process can also contain organic ligands typically used in the field known as a single site catalyst. In a still further embodiment of the invention a compound of a transition metal can also be selected from Group 5 metals, Group 6 metals, Cu, Fe, Co, Ni and/or Pd. The complex of the Group 2 metal is preferably a magnesium complex. The invention will henceforth be described in relation to a preferred embodiment of the process, namely to a process for the preparation of a Ziegler-Natta type catalyst.
A preferred embodiment of the invention is a process for producling catalysts of the Ziegler-Natta type, in the form of
particles having a predetermined size range, comprising: preparing a solution of magnesium complex by reacting an alkoxy magnesium compound and an electron donor or precursor thereof in a C6-C10 aromatic liquid reaction redium; reacting said magnesium complex with a compound of at least one IV valent Gp 4 metal at a temperature greater than 100C and less than 60°C, to produce an emulsion of a denser, TlCl4/toluene-insoluble, oil dispersed phase having, Gp 4 metal/Mg mol ratio 0.1 to 10 in an oil disperse phase having Gp 4 metal/Mg mol ratio 10 to 100; maintaining the droplets of said dispersed phase within the size range 5 to 200 µm by agitation in the presence of an emulsion stabilizer while heating the emulsion to solidify said droplets; and recovering, washing and drying the solidified particles to obtain said catalyst component.
The said disperse and dispersed phases are thus distinguishable from one another by the fact that the denser oil, if contacted with a solution of titanium tetrachloride in toluene, will not dissolve in it. A suitable solution for establishing this criterion would be one having a toluene mol ratio of 0.1 to 0.3. They are also distinguishable by the fact that the great preponderance of the Mg provided (as complex) for the reaction with the Gp 4 metal compound is present in the dispersed phase, as revealed by comparison of the respective Gp 4 metal/Mg mol ratios.
In effect, therefore, virtually the entirety cf the reaction product of the Mg complex with the Gp 4 metal - which is the precursor of the ultimate catalyst component - becomes the dispersed phase, and proceeds through the further processing steps to final dry particulate form. The disperse phase/ still containing a useful quantity of Gp 4 metal, car. be reprocessed for recovery of that metal.
The production of a two-phase, rather than single-phase (as in prior practice) reaction product is encouraged by carrying out the Mg complex/Gp 4 metal compound reaction at low temperature, specifically above 10°C but below 60°C, preferably between above 20°C and below 50°C. Since the two phases will naturally tend to separate into a lower, denser phase and supernatant lighter phase, it is recessary to maintain the reaction product as an emulsion by agitation in the presence of an emulsion stabiliser.
The resulting particles of the dispersed phase of the emulsion are of a size, shape (spherical) and uniformity which render the ultimate catalyst component extremely effective in olefin polymerisation. This morphology is preserved during the heating to solidify the particles, and of course throughout the final washing and. drying steps. It is, by contrast, difficult to the point of impossibility to achieve such morphology through precipitation, because of the fundamental uncontrollability of nucleation and growth, and the large number of variables, which affect these events.
The electron donor is preferably an aromatic carboxylic acid ester, a particularly favoured ester being dioctyl phthalate. The donor may conveniently be formed in situ by reaction of an aromatic carboxylic acid chloride precursor with a C2-C16 alkanol and/or diol. The liquid reaction medium preferably comprises toluene.
Furthermore, emulsifying agents/emulsion stabilisers can be used additionally in a manner known in the art for facilitating the formation and/or stability of the emulsion. For the said purposes e.g. surfactants, e.g. a class based on acrylic or methacrylic polymers can be used. Preferably, said emulsion stabilizers are acrylic or methacrylic polymers, in
particular those with medium sized ester side chains having more than 10, preferably more than 12 carbon atoms and preferably less than 30, and preferably 12 to 20 carbon atoms in the ester side chain. Particular preferred are unbranched C12 to C20 acrylates such as poly (hexadecyl)-methacrylate and poly(octadecyl)-methacrylate.
It has been found that the best results are obtained when the Gp 4 metal/Mg mol ratio of the denser oil is 1 to 5, preferably 2 to 4, and that of the disperse phase oil is 55 to 65. Generally the ratio of the mol ratio Gp 4 metal/Mg in the disperse phase oil to that in the denser oil is at least 10.
Solidification of the dispersed phase particles by heating is suitably carried out at a temperature of 70-150°C, usually at 90-110°C. Preparation of the magnesium corplex may be carried out over a wide range of temperatures, 20 to 80°C being preferred, 50 to 70°C most preferred.
The finally obtained catalyst component is desirably in the form of particles having an average size range of 10 to 200 um, preferably 20 to 50 um.
The present invention further comprehends an olefin polymerisation catalyst comprising a catalyst component prepared as aforesaid, in association with an alkyl aluminium cocatalyst, and optionally with external donors, and the use of that polymerisation catalyst for the polymerisation of C2 to C10-olefins.
The reagents can be added to the reaction medium in any order. However it is preferred that in a first step the alkoxy magnesium compound is reacted with a carboxylic acid halide precursor of the electron donor to form an intermediate; and
in a second step the obtained product is further reacted with the Gp 4 metal. The magnesium compound preferably contains from 1 to 20 carbon atoms per alkoxy group, and the carboxylic acid should contain at least 8 carbon atoms.
Reaction of the magnesium compound, carboxylic acid halide and polyhydric alcohol proceeds satisfactorily at temperatures in the range 20 to 80°C, preferably 50 to 70°C. The product of that reaction, the "Mg complex", is however reacted with the Gp 4 metal compound at a lower temperature, contrary to previous practice, to bring about the formation of a two-phase, oil-in-oil, product.
Use of the aromatic medium for preparation of the Mg complex contributes to consistent product morphology and higher bulk density. Catalyst bulk density and morphology correlate with product bulk density and morphology the so-called "replication effect".
The technique adopted in the novel regimen of the invention is inherently more precise than that formerly employed, and thus further contributes to product consistency, as well as sharply reducing the volumes of solvent to be handled and thus improving process economics.
The reaction medium used as solvent can be aromatic or a mixture of aromatic and aliphatic hydrocarbons, the latter one containing preferably 5-9 carbon atoms, more preferably 5 -7 carbon atoms, or mixtures thereof. Preferably, the liquid reaction medium used as solvent in the reaction is aromatic and is more preferably selected from hydrocarbons such as substituted and unsubstituted benzenes, preferably from alkylated benzenes, even more preferably from toluene and the xylenes, and is most preferably toluene. The molar ratio of said aromatic medium to magnesium is preferably less than 10, for instance from 4 to 10, preferably from 5 to 9.
The recovered particulate product is washed at least once, preferably at least twice, most preferably at least three times with a hydrocarbon, which preferably is selected from aromatic and aliphatic hydrocarbons, preferably with toluene, particularly with hot (e.g. 90°C) toluene. A further wash is advantageously performed with heptane, most preferably with hot (e.g. 90°C) heptane, and yet a further wash with pentane. A washing step typically includes several substeps. A favoured washing sequence is, for example, one wash with toluene at 90°C, two washes with heptane at 90°C and one or two washes with pentane at room temperature.
The washing can be optimized to give a catalyst with novel and desirable properties. Finally, the washed catalyst component is dried, as by evaporation or flushing with nitrogen.
It is preferable that the intermediates as well as the final product of the process be distinct compounds with an essentially stoichiometric composition. Often, they are complexes. A complex is, according to Rompps Chemie-Lexicon, 1. Edition, Franckh'sche Verlagshandlung, W. Keller & Co., Stuttgart, 1973, page 1831, "a derived name of compounds of higher order, which originate from the combination of molecules, - unlike compounds of first order, in the creation of which atoms participate".
The alkoxy magnesium compound group is preferably selected from the group consisting of magnesium dialkoxides, complexes of a magnesium dihalide and an alcohol, and complexes of a magnesium dihalide and a magnesium dialkoxide. It may be a reaction product of an alcohol and a magnesium compound selected from the group consisting of dialkyl magnesiums,
alkyl magnesium alkoxides, alkyl magnesium halides and magnesium dihalides. It can further be selected from the group consisting of dialkyloxy magnesiums, diaryloxy magnesiums, alkyloxy magnesium halides, aryloxy magnesium halides, alkyl magnesium alkoxides, aryl magnesium alkoxides and alkyl magnesium aryloxides.
The magnesium dialkoxide may be the reaction product of a magnesium dihalide such as magnesium dichloride or a dialkyl magnesium of the formula R2Mg, wherein each one of the two Rs is a similar or different C1-C2o alkyl, preferably a similar or different C4-C10 alkyl. Typical magnesium alkyls are ethylbutyl magnesium, dibutyl magnesium, dipropyl magnesium, propylbutyl magnesium, dipentyl magnesium, butylpentylmagnesium, butyloctyl magnesium and dioctyl magnesium. Most preferably, one R of the formula R2Mg is a butyl group and the other R is an octyl group, i.e. the dialkyl magnesium compound is butyl octyl magnesium.
Typical alkyl-alkoxy magnesium compounds RMgOR, when used, are ethyl magnesium butoxide, butyl magnesium pentoxide, octyl magnesium butoxide and octyl magnesium octoxide.
Dialkyl magnesium, alkyl magnesium alkoxide or magnesium dihalide can react with a polyhydric alcohol R'(OH)m, or a mixture thereof with a monohydric alcohol R'OH.
Typical C2 to C6 polyhydric alcohols may be straight-chain or branched and include ethylene glycol, propylene glycol, trimethylene glycol, 1,2-butylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, 2,3-butylene glycol, 1,5pentanediol, 1,6-hexanediol, 1,8-octanediol, pinacol, diethylene glycol, triethylene glycol, and triols such as glycerol, methylol propane and pentareythritol. The polyhydric alcohol can be
selected on the basis of the activity and morphology it gives the catalyst component.
The aromatic reaction medium may also contain a monohydric alcohol, which may be straight- or branched-chain. Typical C1 -C2o monohydric alcohols are methanol, ethanol, n-propanol, iso-propanol, n-butanol, iso-butanol, sec.biitanol, tert.butanol, n-amyl alcohol, iso-amyl alcohol, sec.amyl alcohol, tert.amyl alcohol, diethyl carbinol, akt. amyl alcohol, sec. isoamyl alcohol, tert.butyl carbinol. Typical C6-C10 monohydric alcohols are hexanol, 2-ethyl-lbutanol, 4-methyl-2-pentanol, 1-heptanol, 2-heptanol, 4-heptanol, 2,4-dimethyl-Spentanol, 1-octanol, 2-octanol, 2-ethyl-l-hexanol, 1-nonanol, 5-nonanol, diisobutyl carbinol, 1-decanol and 2,7-dimethyl-2-octanol. Typical >C10 monohydric alcohols are n-1-undecanol, n-1-dodecanol, n-1-tridecanol, n-1-tetradecanol, n-1-pentadecanol, 1 -hexadecanol, n-1-heptadecanol and n-1-octadecanol. The monohydric alcohols may be unsaturated, as long as they do not act as catalyst poisons.
Preferable monohydric alcohols are those of formula R'OH in which R1 is a C2-C6 alkyl group, most preferably a C4-C12 alkyl group, particularly 2-ethyl-l-hexanol.
Preferably, essentially all of the aromatic carboxylic acid ester is a reaction product of a carboxylic acid halide, preferably a dicarboxylic acid dihalide, more preferably an unsaturated α,β-dicarboxylic acid dihalide, most preferably phthalic acid dichloride, with the monohydric alcohol.
The compound of a four-valent Gp 4 metal compound containing a halogen is preferably a titanium tetrahalide. Equivalent to titanium tetrahalide is the combination of an alkoxy titanium
halide and a halogenation agent therefore, which are able to form a titanium tetrahalide in situ. The most preferred halide is the chloride, for zirconium and hafnium as well as for titanium.
The reaction conditions used in the claimed process may be varied according to the used reactants and agents.
As is known, the addition of at least one halogenated hydrocarbon during the process can lead to further improved catalytic activity. Reactive halogenated hydrocarbons preferably have the formula R'"X'"n wherein R'" is an n-valent C1-C2o hydrocarbyl group, particularly a C1-C10 paraffin, X'" is a halogen and n is an integer from 1 to 4.
Such chlorinated hydrocarbons include monochloromethane, dichloromethane, trichloromethane (chloroform), tetrachloromethane, monochloroethane, (1,1)-dichloroethane,
(1,2)-dichloroethane, (1,1,1)-trichloroethane, (1,1,2)-trichloroethane, (1,1,1,2}-tetrachloroethane, (1,1,2,2) tetrachloroethane, pentachloroethane, hexachloroethane, (1)-chloropropane, (2)-chloropropane, (1,2)-dichloropropane,
(l,3)-dichloropropane, (1,2,3)trichloropropane, (1)-chlorobutane, (2)-chlorobutane, isobutyl chloride, tert.butyl chloride, (1,4)-dichlorobutane, (1)-chloropentane, (1,5)-dichloropentane. The chlorinated hydrocarbons may also be unsaturated, provided that the unsaturation does not act as catalyst poison in the final catalyst component.
In the above formula, R1" is preferably a mono-or bivalent C1-C10 alkyl group , independently, X'" is preferably chlorine and, independently, n is preferably 1 or 2. Preferred compounds include butyl chloride (BuCl), dichloroalkanes such as (l/4-) dichlorobutane, and tertiary butyl chloride.
Though the catalyst preparation according to the inventive method can be carried out batchwise, it is also preferable and possible to prepare the catalyst component semi-continuously our continuously. In such semi-continuous or continuous process, the solution of the complex of the Group 2 metal and said electron donor, which is prepared by reacting the compound of said metal with said electron donor in an organic liquid reaction medium, is mixed with at least one compound of a transition metal, which might be solved in the same or different organic liquid reaction medium. The so obtained solution is then agitated, possibly in the presence of an emulsion stabilizer, and then the so-agitated emulsion is fed into a temperature gradient reactor, in which the emulsion is subjected a temperature gradient, thus leading to solidifying the droplets of a dispersed phase of the emulsion.
When feeding said agitated emulsion to the temperature gradient reactor, an inert solvent, in which the droplets are not soluble, can additionally be fed into that gradient reactor in order to improve the droplet formation and thus leading to a uniform grain size of the particles of the catalyst component, which are formed in the temperature gradient reactor when passing through said line. Such additional solvent might be the same as the organic liquid reaction medium, which is used for preparing the solution of the complex of the Group 2 metal as explained above in more detail.
The solidified particles of the olefin polymerisation catalyst component can subsequently be recovered by an in-stream filtering unit and then, optionally after some additional washing and drying steps in order to remove unreacted starting components, can be stored for further use. In one embodiment the catalyst can be fed after washing steps into the olefin polymerisation reactor, so that a continuous preparation and fed to the reactor is guaranteed.
As it can be seen from the above description of the semi- continuous or continuous process, it is thus possible to use separated reaction vessels for the different process steps and to transfer the reaction products which are prepared in the respective reaction vessels and to fed them in-line into further reaction vessels for formation of the emulsion and, subsequently, of the solidified particles.
It is one possibility to use a full-continuous process as the time saving in said process is remarkable. In such fully continuous process, the formation of the solidified particles could be carried out in the temperature gradient line in the kind of pipe reactor, which is sufficiently long and which is subjected said temperature gradient from the starting temperature in the lower range of 20 to 80°C up to a "solidifying"temperature of 70 to 150°C. The temperature gradient is preferably obtained by means of heating the pipe reactor from the outside by applying normal heaters, microwaves, etc.
As mentioned before, a filtering unit might preferably be used for filtering the solidified particles from the solvent stream. For said filtering unit, various drums and sieving systems can be used, depending on the specific particle sizes.
STATEMENT OF INVENTION
In accordance with the present invention, it relates to a process for producing an olefin polymerisation catalyst component in the form of solidified particles, comprising; preparing a solution of a complex of a Gp 2 metal and an electron donor by reacting a compound of said Gp 2 metal with said electron donor or a precursor thereof in an organic liquid reaction medium, reacting said complex obtained in the previous step, in solution, with at least one compound of a transition metal to produce an emulsion having a dispersed phase in the form droplets, wherein the dispersed phase contains more than 50 mol% of the Gp 2 metal in said complex; maintaining the droplets of said dispersed phase within the average size range 5 to 200 µm by agitation in the presence of an emulsion stabilizer and solidifying said droplets to obtain solidified particles; and recovering, washing and drying said particles to obtain said catalyst component.
In accordance with the present invention, it relates to an olefin polymerisation catalyst component such as herein described.
Some preferred embodiments of the invention are described, by way of illustration, in the following Examples.
EXAMPLE 1 A magnesium complex solution was prepared by slowly adding
over a 40 minute period, with stirring, 110 ml of a 20% solution in toluene of BOMAG-A (Tradename) [Mg(Bu)1.5 (Oct)0.5] to 38.9 ml of 2-ethylhexanol which had been cooled to 5°C in a 300 ml glass reactor. During the addition the reactor contents were maintained below 15°C. The temperature was then raised to 60°C and held at that level for 30 minutes with stirring, at which time reaction was complete, 6.4 ml phthaloyl chloride was then added over an 11 minute period. The reactor contents were stirred at 60°C for 20 minutes, 12.9 ml 1-chlorobutane was added, and stirring continued for another 15 minutes at 60°C. The resulting stable, yellowish Mg complex solution was cooled to room temperature.
19.5 ml TiCl4, 5 ml heptane and 28.7 of the above-prepared Mg complex solution were reacted at 25°C in a 300 ml glass reactor. After 5 minutes, reaction was complete and a dark red emulsion had formed. The temperature was raised to 50°C, 2 ml of Viscoplex 1-254 (Tradename) (40-44% of acrylic polymer in base oil) was added, and the reactor contents were stirred for 3.0 minutes. The resulting stabilized emulsion was then heated to 90°C, with stirring, for 10 minutes to solidify the particles forming the dispersed phase. After settling and syphoning the solids (2.6 grams) underwent washing with:
1. 100 ml toluene at 90°C for 30 minutes;
2. 60 ml heptane, at 90°C for 20 minutes;
3. 60 ml heptane, at 35°C for 10 minutes,
4. 60 ml pentane, at 30°C for 5 minutes; and
5. 60 ml pentane, at 30°C for 5 minutes.
The solids were then dried at 60°C by nitrogen purge. The particles were established by microscopic examination to be perfectly spherical in shape. The Coulter PSD is shown in Figure -1.
EXAMPLE 2
Example 1 was repeated, in order to evaluate the consistency of the procedure. The quantity of solids product was 2.6 g, the particles perfectly spherical. The Coulter PSD is shown in Figure 2.
TABLE 1

(Table Removed 1)
* Di-ethyl-hexyl phthalate (internal electron donor)
** Measured with Coulter LS200 at room temperature with n-
heptane as medium
EXAMPLES 3 and 4
The products of Examples 1 and 2 were evaluated as catalyst components in propylene polymerisation ir. the following manner.
0.9 ml triethyl aluminium (TEA) (co-catalyst), 0.12 ml cyclohexyl methyl dimethoxy silane (CMMS: as an external donor and 30 ml n-pentane were mixed and allowed to react for 5 minutes. Half of the mixture was then added to a polymerisation reactor and the other half was mixed with 20 mg of the components prepared in Examples 1 and 2. After an additional 5 minutes the component TEA/dcnor/n-pentane mixture was added to the reactor. The Al/Ti mole ratio of the resulting polymerisation catalyst was 250 mol/mol and the Al/CMMS mole ratio was 10 mol/mol.
Propylene bulk polymerisation was carried out in a stirred 5 1
tank reactor.
7O mmol hydrogen and 1400 g propylene were introduced into the reactor and the temperature was raised within 15 minutes to the polymerisation temperature of 70°C. The polymerisation time at 70°C was 60 minutes, after which the polymer formed was taken out from the reactor. Example 3 employed the catalyst containing component of Example 1 and Example 4 that of Example 2.
The results of the polymerisation evaluations are summarised in the following Table 2.
TABLE 2

(Table Removed 2)
ISO 1133, 2.16 kg load at 230°C xylene-soluble fraction of product at 25°C polymer-bulk density (ASTM D 1895}
The polymer particles were spherical, with a markedly narrow size distribution: more than 75% of the product was of 0.5-1.00 mm particle diameter.
Examples 5-8
In following examples poly(hexadecylmethacrylate)in different amounts (Examples 5-7) and poly(octadecylmethacrylate) (Example 8), both available from Aldrich, were used in stead of Viscoplex.
Preparation of the soluble Mg-complexes
Method A)
In a 150 1 steel reactor 19,4 kg of 2-ethyl hexanol were added at 20 °C. 56,0 kg of a 20 % BOMAG A solution in toluene were then slowly added to the well stirred alcohol. The temperature of the mixture was then increased to 60 °C, and the reactants were allowed to react for 30 minutes at this temperature. After addition of 5,5 kg of 1,2-phthaloyl dichloride, the reaction mixture was stirred at 60 °C for another 30 minutes to ensure complete reaction. 13.8 kg of 1-chloro butane were then added at 60 °C, and stirring at -this temperature was continued for 30 minutes. After cooling to room temperature a yellow solution was obtained.
Method B)
In a 300 ml glass reactor 38,9 ml of 2-ethyl hexanol were added at 20 °C. 110,0 ml of a 20 % BOMAG A solution in toluene were then slowly added to the well stirred alcohol. The temperature of the mixture was then increased to 60 °C, and the reactants were allowed to react for 60 minutes at this temperature. After addition of 6,4 ml of 1,2-phthaloyl dichloride, the reaction mixture was stirred at 60°C for another 60 minutes to ensure complete reaction. After.cooling to room temperature a yellow solution was obtained.
Example 5
Preparation of the catalyst component
19,5 ml titanium tetrachloride were placed in a 300 ml glass reactor equipped with a mechanical stirrer. After addition of 5,0 ml n-heptane, 31,0 g of the Mg-complex (method A) was added to the well-stirred reaction mixture at 25 °C. Mixing speed was kept constant 170 rpm through whole synthesis. After addition a dark red emulsion was formed. The temperature was
increased to 50 °C and 0,9 ml poly(hexadecyl methacrylate)-toluene solution was added. After 30 min mixing, the temperature was increased to 90°C and then after 10 min the mixing was stopped and the catalyst was let to settle. After siphoning, the solid was washed with 100 ml of toluene at 90 °C for 30 min. Then the washings were continued with two times 60 ml heptane and twice with 60 ml pentane. The first heptane washing took 20 min at 90 °C and the second one 10 min. During the second heptane wash the temperature was decreased down to c. 25 °C. The pentane washing was then carried out for 5 min at c. 25°C.
Finally the solid catalyst was dried at 60°C by purging nitrogen through the catalyst bed. Catalyst composition is shown in TABLE 3.
The catalyst particle size distribution by Coulter is shown in Figure 3.
Bulk polymerisation of propylene
The propylene bulk polymerisation was carried out as in Example 3 but using the catalyst of example 5. Polymerisation results are disclosed in TABLE 4.
Polymer particle size distribution by sieving is disclosed in TABLE 5.
Example 6
The catalyst preparation and polymerisation were carried out
as in the Example 5, except 0,45 ml poly(hexadecyl
methacrylate)-toluene solution was used in catalyst
preparation.
Catalyst composition is disclosed in TABLE 3 and
polymerisation results in TABLE 4 and polymer particle size
distribution in TABLE 5.
The catalyst particles were spherical and catalyst particle size distribution by Coulter is shown in Figure 4.
Example 7
The catalyst preparation and polymerisation were carried out
as in the Example 5, except 1,35 ml poly(hexadecyl
methacrylate)-toluene solution was used in catalyst
preparation. Catalyst composition is disclosed in TABLE 3 and
polymerisation results in TABLE 4 and polymer particle size
distribution in TABLE 5.
The catalyst particles were spherical.
The catalyst particle size distribution by Coulter is shown in
Figure 5.
Example 8
Example 8 was done as Example 5, but Mg complex (method B) was used and the poly(octadecyl methacrylate)-toluene solution was used instead of poly(hexadecyl methacrylate).
The catalyst particles were spherical. Catalyst composition is disclosed in TABLE 3 and polymerisation results in TABLE 4 and polymer particle size distribution in TABLE 5. The catalyst particle size distribution by Coulter is shown in Figure 6.
TABLE 3 - Catalyst composition

(Table Removed 3)
TABLE 4 - Polymerisation results

(Table Removed 4)
TABLE 5. Polymer particle size distribution by sieving.
% Polymer on sieves

(Table Removed 5)

We claim:
1. The process for producing an olefin polymerisation catalyst component in the form of
particles having a predetermined size range, comprising:
preparing a solution of a complex of a Gp HA metal and an electron donor by reacting a compound of said metal with said electron donor or a precursor thereof in an organic liquid medium, wherein the preparation of the Gp IIA metal complex is carried out at a temperature of 20 to 80 °C;
reacting said complex, in solution, with at least one compound of a transition metal, at a temperature of 10 to 60 °C, to produce an emulsion, wherein said emulsion is composed of a dispersed phase which is a TiCl4/toluene -insoluble oil having a Gp IVB metal/Mg mol ratio greater than 0.1 and less than 10 and a disperse phase which is an oil less dense than that of the dispersed phase and which has a Gp IVB metal/Mg mol ratio of 10 to 100, the dispersed phase of which contains more than 50 mol% of the Gp IIA metal; maintaining the particles of said dispersed phase within the average size range 10 to 200 urn by agitation in the presence of an emulsion stabilizer and solidifying said particles, wherein the solidification of said particles is effected by heating; and recovering, washing and drying said particles to obtain said catalyst component.
2. The process as claimed in claim 1, wherein said transition metal is Gp IVB metal.
3. The process as claimed in claim 1 or claim 2, wherein said Gp IIA metal is magnesium.
4. The process as claimed in any preceding claim, wherein said medium comprised a C6-C10 aromatic hydrocabron.
5. The process as claimed in claim 1, wherein the Gp IVB metal/Mg mol ratio of said disperse phase is 20 to 80,
6. The process as claimed in claim 1, wherein the Gp IVB metal/Mg mol ratio of said disperse phase is 45 to 75.
7. The process as claimed in any preceding claim, wherein said electron donor is an aromatic
. carboxylic acid erter.

8. The process as claimed in any preceding claim, wherein said electron donor is dioctyl phthalate.
9. The process as claimed in any preceding claim, wherein said liquid reaction medium comprises toluene.
10. The process as claimed in any of claims 2 to 9, wherein said Gp IVB metal is titanium.
11. The process as claimed in any of claims 2 to 10, wherein said compound of a Gp IVB metal is halide, wherein the halide is chloride.
12. A process according to any of claims 3 to 11 wherein said magnesium complex and Gp IVB metal compound are reacted at a temperature of greater than 20 °C to less than 50 °C.
13. The process as claimed in any preceding claim, wherein said emulsion stabilizer is a surfactant.
14. The process as claimed in claim 13, wherein said surfactant comprises an acrylic or methacrylic polymer.
15. The process as claimed in any of claims 1 and 5 to 13, wherein the Gp IVB metal/Mg mol ratio of said denser oil is 2 to 4 and that of the disperse phase oil is 55 to 65.
16. The process as claimed in claim 15, wherein the ratio of the mol ratio Gp IV metal/Mg in the disperse phare oil to that in said denser oil is at least 10.
17. The process as claimed in any of claims 1 to 15, wherein the emulsion is heated to a temperature of 70-150 °C to solidify said particles.

18. The process as claimed in claim 17, wherein the temperature to which the emulsion is
heated is 90-110 °C.
19. The process as claimed in claim 1, wherein the Gp HA metal is magnesium and the
preparation of the magnesium complex is carried out at a temperature of 50 to 70 °C.
20. The process as claimed in claim 1, wherein said transition metal is a Gp VB metal and a
Gp VIB metal.
21. The process as claimed in claim 1, wherein said transition metal is Cu, Fe, Co, Ni and Pd.
22. The process as claimed in any preceding claim wherein said obtained catalyst component is in the form of particles having an average size range of 10 to 200 urn.
23. A process as claimed in claim 22, wherein said particles have an average size range of 20
to 50 urn.
24. An olefin polymerisation catalyst component prepared according to the process as claimed
in any one of the claims 1 to 23.
25. An olefin polymerisation catalyst component as claimed in the previous claims, whenever used for the polymerization of the C2 to C10 α-olefins.

"PREPARATION OF OLEFIN POLYMERISATION CATALYST COMPONENT."

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