GB2028843A - alpha -olefin polymerization, catalysts therefor and components for such catalysts - Google Patents

Abstract

A catalyst component, solid (II), is prepared by reacting a trivalent metal halide with a hydroxide, oxide or carbonate of a divalent metal, a double compound containing any such compound, or a hydrate of a divalent metal compound thereby to form a solid product (I); and reacting the solid product (I) with an electron donor comprising one or more electron donor compounds, and with an electron acceptor comprising titanium tetrachloride and optionally one or more other electron acceptor compounds, thereby to form a solid product (II), the electron donor and/or the electron acceptor being reacted with the solid product (I) in at least two separate portions. Reaction of the catalyst component with an organoaluminium compound gives an alpha -olefin homo- or co- polymerization catalyst.

Description

SPECIFICATION ry-Olefin polymerization, catalysts therefor and components for such catalysts The present invention relates to polymerization of a-olefins.

In particuiar it relates to a catalyst component for such a polymerization prepared from a trivalent metal halide, a diva lent metal compound, an electron donor, and an electron acceptor; to a catalyst prepared from such a component by reaction with an organoaluminium compound; and to a method of polymerization of anlefins using such a catalyst.

Various inventions have heretofore been proposed which employ an electron donor in the preparation of a catalyst for a-olefin polymerization.

For example, catalysts comprising as a main component a carrier, MgCI2 (anhydrous), a solid having a Mg-Cl bond, magnesium carbonate, oxides or hydroxides of elements of Group II or Group VIII of the Periodic Table, etc, and together with an electron donor, have been put forward.

On the other hand, the present inventors and colleagues have heretofore developed catalysts for ethylene or other -oiefin polymerization which are prepared by reacting a trivalent metal halide with a divalent metal compound to form a solid product (I) and then supporting a transition metal compound on the solid product (I) in various manners. For example, a method wherein a solid product obtained by reacting said solid product (I) with a polysiloxane or an electron donorflnd then further reacting the resulting material with a transition metal compound to give a catalyst is described in British Patent No.

1,496,440 which corresponds to Japanese Patent Application No. 50994/1 974 and in Japanese Patent Application No. 127750/1977; a method wherein a product obtained by adding to said solid product (I), a polysiloxane or an electron donor and a transition metal compound at the same time, or adding thereto a cbmplex of a polysiloxane. with a transition metal compound or a complex of an electron donor with a transition metal compound prepared in advance to give a catalyst component is described in British Patent Application No. 7906776 Serial 201 7722 which corresponds in part to Japanese Patent Applicationa Nos. 21246/1 978. 2 1247/1 978 and 32031/1978, etc; a method wherein a product is obtained by reacting said solid product (I) with a transition metal compound, and then once reacting the resulting material with a trivalent metal alcoholate, and thereafter reacting the resulting material again with a transition metal compound is described in British Patent Application No.

32145/76, Specification No.1546718, which corresponds to Japanese Patent Application No.

96427/1975 and U.S. Patent No. 4,076,922.

The present inventors have made various studies for improving their prior inventions, and as a result, have found that the effectiveness can vary greatly depending upon the manner in which said solid product (I) is reacted with an electron donor and electron acceptor.

As a result of the inventors' further studies on the manner of reaction, there is now provided a method for preparing as a solid product (II) a component for an a-olefin -polymerization catalyst, the method comprising reacting a trivalent metal halide with a hydroxide, oxide or carbonate of a divalent metal, a double compound containing any such compound, or a hydrate of a divalent metal compound thereby to form a solid product (I); and reacting the solid product (I) with an electron donor comprising one or more electron donor compounds, and with an electron acceptor comprising titanium tetrachloride and optionally one or more other electron acceptor compounds, thereby to form a solid product (II), the electron donor and/or the electron acceptor being reacted with the solid product (I) in at least two separate portions.

In the present method firstly a trivalent metal halide is reacted with a diva lent metal compound to obtain a solid product (I).

The trivalent metal halide can be, for example, aluminum trichloride (anhydrous), aluminum tribromide (anhydrous) or ferric chloride (anhydrous), particularly aluminum trichloride. The divalent metal compound can be, for example, a hydroxide such as Mg(OH)2, Ca(OH)2, Zn(OH)2 or Mn(OH)2, particularly Mg(OH)2; an oxide such as MgO, CaO, ZnO or MnO, particularly MgO; å double oxide containing a diva lent metal such as MgAl204, MgaSiO4 or Mg6MnO8; a carbonate or double carbonate such as MgCO3,MnCO3 or MgCO3.CaCO3, particularly MgCO3; a hydrated halide such as SnCl2.2H 20, MgCl2.nH2O(n = 1 to 6), NiCI2.6H20, MnCI2.4H20, or KMgCI,.GH,O; a hydrate of a mixed halide and hydroxide such as MgCl2.nMg(OH)2.mH2O (n = 1 to 3, m = 1 to 6); a hydrate of a double oxide such as 3Mg0.2SiO2.2H20; a hydrate of a double compound of a carbonate and a hydroxide such as 3MgCO3.Mg(OH)2.3H20; a hydrate of a double compound of a hydroxide and a carbonate, containing a diva lent metal, such as MgAI2(OH)1 CO3. 4H2 0; or a like compound.

The solid product (I) can be prepared as follows: It is preferable to mill the trivalent metal halide together with the diva lent metal compound, in a ball mill for 5-50 hours, or in a vibrating mill for 1-10 hours to bring them into a sufficiently mixed state. As for the mixing ratio, 0.1-20 mol of divalent metal compound per mol of trivalent metal halide is usually sufficient A particularly preferable range is 1-10 mol per mol. The reaction temperature is usually in the range of room temperature (2;00C) to 5000C, preferably 500-3000C. The reaction time is suitably in the range of 30 minutes to 50 hours.In the case of the lower reaction temperatures, reaction should be carried out for a long time to effect sufficient reaction so that substantial amounts of unreacted trivalent metal may not remain.

The solid product thus obtained, which is referred to as solid product (I), is then reacted with an electron donor (which will be abbreviated to "ED") and an electron acceptor (which will be abbreviated to "EA").

ED compounds which can be employed in the present reaction include organic compounds containing at least one oxygen, nitrogen, silicon, sulphur or phosphorus atom. Such compounds include alcohols, ethers, esters, aldehydes, carboxylic acids, ketones, nitriles, isocyanates, azo compounds, phosphines, phosphites, phosphinites, thioethers, thioalcohols, and polysiloxanes, among others, but particularly esters.As for concrete examples, one can employ alcohols such as methanol, ethanol, propanol, butanol, pentanol, hexanol, octanol, phenol, cresol, xylenol, ethylphenol, naphthol or cumyl alcohol; ethers such as diethyl ether, di-n-propyl ether, di-n-butyl ether, di4-amyl ether, di-n-pentyl ether, di-n-hexyl ether, di-n-octyl ether, di-i-octyl ether, ethylene glycol monomethyl ether, diphenyl or tetrahydrofuran; esters such as ethyl acetate, butyl formate, amyl acetate, vinyl butyrate, vinyl acetate, methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, octyl benzoate, 2-ethylhexyl benzoate, methyl toluylate, ethyl toluylate, 2-ethylhexyl toluylate, methyl anisate, ethyl anisate, propyl anisate, ethyl cinnamate, methyl naphthoate, ethyl naphthoate, propyl naphthoate, butyl naphthoate, 2- ethylhexyl naphthoate or ethyl phenylacetate; aldehydes such as acetaldehyde or benzaldehyde; carboxylic acids such as formic acid, acetic acid, propionic acid, butyric acid, oxalic acid, succinic acid, acrylic acid, maleic acid or benzoic acid; ketones such as methyl ethyl ketone, methyl isobutyl ketone or benzophenone; nitriles such as acetonitrile; amines such as methylamine, diethylamine, tributylamine, triethanolamine, pyridine or aniline; isocyanates such as phenylisocyanate or toluylisocyanate; azo compounds such as azobenzene; phosphines such as ethylphosphine, triethylphosphine, tri-nbutylphosphine, tri-n-octylphosphine ortriphenylphosphine; phosphites such as dimethylphosphite, din-octylphosphite, tri-n-butylphosphite or triphenylphosphite; phosph in ites such as ethyldiethylphosphin ite, ethyldibutylphosphinite or phenyldiphenylphosphinite; thioethers such as diethyl thioether, diphenyl thioether, methyl phenyl thioether, ethylene sulphide or propylene sulphide; and thioalcohols such as ethyl thioalcohol, n-propyl thioalcohol and thiophenol.

As for polysiloxanes, chain or ring-form siloxane polymers with a repeating unit expressed by the general formula -R1Si(R2)O- (wherein R1 and R2 represent the same or different substituents and may be the same or different along the polymer backbone) may be employed, especially those wherein R1 and R2 each represent one or more of hydrogen, a hydrocarbyl group such as an alkyl or aryl group, a halogen, an alkoxy group, an aryloxy group or a residue from a carboxylic acid group.

Concrete examples of polysiloxanes which are usually preferably employed include lower polymers such as octamethyltrisoloxane or octaethylcyclotetrasiloxane; alkylsiloxane polymers such as dimethylpolysiloxane, ethylpolysiloxane or methylethylpolysiloxane; arylsiloxane polymers such as hexaphenylcyclotrisiloxane or diphenylpolysiloxane; and alkylarylsiloxane polymers such as diphenyloctamethyltetrasiloxane or methylphenylpolysiloxane. It is also possible to employ these various polysiloxane compounds in admixture. It is necessary for the polysiloxane to be in the liquid state at the time of reaction, and thus it is necessary to use liquid polysiloxanes or polysiloxanes dissolved in a solvent.The viscosity of such polysiloxanes is in the range of 10-10,000 centistokes at 250 C, preferably 10-2,000 centistokes.

The above-mentioned various organic compounds which are EDs can be employed not only singly but also in admixture.

The EA employed in the method of the present invention is TICS, or TiC14 with one or more other ED compounds. Representatives of the other EDs are halides of elements of groups Ill-V of the Periodical Table. Concrete examples include AICI3 (anhydrous), SiCI4, SnCl2, SnCI4, ZrC14, PAL3, PCls, VCI4, SbCi5, SCI2, MnCI2, FeCI2 and NiCI2, particularly SiC14. These compounds may also be employed in admixture, but as mentioned it is necessary to employ TiC14.

For the method of reacting the solid product (I) with ED and EA there are various possibilities.

Embodiments wherein a few reaction steps are taken are mentioned later, and for any of these reaction steps it is possible to carry out them in the presence or absence of solvent, in suspension state or while milling the materials by means of a vibrating mill or a ball mill.

In the reaction of saidsolid product (I) with ED and EA, it is an important feature of the present invention to react either one or both of ED and EA in two or more divided ie. separate portions, and yet employ titanium tetrachloride as at least one EA compound.

As for concrete and representative embodiments relative to the order of the reaction steps, there are the following examples of methods (wherein subscripts generally indicate that the ED or EA, as the case may be, comprises more than one ED or EA compound and specifically indicate the number of the ED or EA compound): i) The method of reacting said solid product (I) with ED and EA1 and then reacting the resulting material with EA2 (TiCI4) once or twice.

ii) The method of reacting said solid product (I) with EA1 and then reacting the resulting material with ED and EA2 (fiCI4).

iii) The method of reacting said solid product (I) with ED, and EA1 and then reacting the resulting material with ED2 and EA2 (TiCI4).

iv) The method of reacting said solid product (I) with EDt and EA (TiCI4) and then reacting the resulting material with ED2.

v) The method of reacting said solid product (I) with EDr and then reacting the resulting material with ED2 and EA (TiCI4).

vi) The method of reacting said solid product (I) with ED, and then reacting the resulting material with ED2 and further reacting the resulting material with EA (TiCI4), once or twice.

vii) The method of reacting said solid product (I) with ED, and then reacting the resulting material with ED2 and further reacting the resulting material with ED3 and EA (TiC 14).

viii) The method of reacting said solid product (I) with Ed and then reacting the resulting material with EA (TiC14) twice.

ix) The method of reacting said solid product (I) with ED and then reacting the resulting material with EA, and further reacting material with EA2 (TiCI4).

The above-mentioned reaction of the solid product (I) with divided ED and/or EA may usually be carried out with two or three divided portions. More divided portions make the operation complicated, and do not improve the effectivenesses accordingly. Further the reaction of said solid product (I) with an ED and EA compound together refers to either reaction of said solid product (I) with coexistent ED and EA or a complex of ED with EA. Still further, if necessary, it is possible to add a solvent at a desired time of the reaction.Solvents employed therefor are so-called inert solvents such as aliphatic hydrocarbons, eg. n-pentane, n-hexane, n-heptane, n-octane, i-octane, n-nonane or n-decane: aromatic hydrocarbons, eg. benzene, toluene, xylene, ethylbenzene or cumene; and halogenated hydrocarbons, eg. carbon tetrachloride, chloroform, dichloroethane, trichloroetbylene, tetrachloroethylene, carbon tetrabromide, chlorobenzene or o-dichlorobenzene.

As for the amounts of ED, EA and solvent employed, a range -of 1-5,000 g of ED, a range of 1-5,000 g of EA and a range of 0--5,000 ml of solvent, each based on 100 g of said solid product (I), are preferable.

As for the reaction conditions, a reaction temperature range of 0--5000C, preferably 20--2000C, may be employed depending on each reaction step, and the reaction time range may be appropriately varied depending on the reaction manner, for example, one minute to 10 hours in case of suspension state, 5 to 200 hours in case of ball mill and 10 minutes to 50 hours in case of vibrating mill.

After completion of the reaction, any resulting liquid portion containing unreacted ED or EA is removed under reduced pressure or by atmospheric distillation, or subjected to separation by filtration or decantation to separate the liquid portion, and if necessary, washed with a solvent and dried, to obtain a solid product (II).

Moreover, with regard to the removal of unreacted materials, it is most desirable to carry out such removal at each reaction step.

It is also possible however to take the suspension containing solid (11) and solvent, as it is, without separating solid therefrom, for the next reaction.

The solid product (II) thus obtained is then combined with an organoaluminium compound to give a catalyst which may be employed for a-olefin polymerization.

The organoaluminium compounds employed in this reaction include those expressed by the general formula AIR R1 nXI--(n+n') (wherein R and R' each represent a hydrocarbon group such as alkyl group, aryi group, alkaryl group, cycloalkyl group, etc. or an alkoxy group, X represents a hydrogen atom or a halogen atom such as chlorine, bromine or iodine, and n and n' each represent an integer but satisfy the condition that O < n + n'= < 3 As for concrete examples, trialkylaluminiums such as trimethylaluminium, triethylaluminium, tri-n-propyialuminium, tri-n-butylaluminium, tri-i-butylalum inium, tri-n hexylaluminium, tri-i-hexya luminium, tri-2-methylpentylaluminium, tri-n-octylaluminium and tri-n decylaluminiu m; dialkylaluminium monohalides such as diethylaluminium monochloride, di-n propylaluminium monochloride, di-i-butylaluminium monochloride, diethyla lum inium monofluoride, diethylaluminium monobromide and diethyla luminium monoiodide; alkylaluminium hydrides such as diethylaluminium hydride; and alkylaluminium halides such as methylaluminium sesquichloride, ethylaluminiu m sesquichloride, ethylaluminium dichloride and i-butylaluminium can be mentioned, as well as alkoxyalkylaluminiums such as monoethoxydiethylaluminium.

A suitable proportion of organoaluminium to be combined with said solid product (II) is in the - range of 50-5,000 g of an organoaluminium compound based on 100 g of said solid product (II).

Merely admixing the two together, a catalyst having an activity suitable for aolefin polymerization as it is can be obtained, and employed in the same manner as in the case of a conventional Ziegler-Natta catalyst.

A polymerization reaction in accordance with the reaction can be carried out in a hydrocarbon solvent such as n-hexane, n-heptane, n-octane, benzene, toluene or the like, though it is also possible to carry out the reaction without employing any solvent, but in a liquefied a-olefin monomer such as liquefied propylene, liquefied butene-1, or the like. Polymerization is normally carried out at a polymerization temperature of room temperature (200C) to 20000 C, under a polymerization pressure of atmospheric pressure (0 kg/cm2G) to 50 kg/cm2G, usually for 5 minutes to 10 hours. In the polymerization, an appropriate amount of hydrogen may be added to control the molecular weight, as in conventional polymerization.

As for the a-olefin employed in the present polymerization, straight-chain monooiefins such as ethylene, propylene, butene-1, hexene-1, hexene-1, octene-1 , decene-1, etc. particularly propylene; branched chain monoolefins such as 4-methyl-pentene-1, 2-methyl-pentene, 3-methyl-butene-1, etc; diolefins such as butadiene, isoprene, chloroprene; and styrene, etc are still suitable. In the polymerization method of the present invention, it is possible to carry out not only homopolymerization of such an a-olefin, but also copolymerization of a combination of different cr-olefins, such as propylene with ethylene, propylene with butene-1, etc.

A first effectiveness which can be obtained by a polymerization method in accordance with the present invention consists in that very highly crystailine a-olefin polymers may be obtained. For example, according to the above-mentioned previous inventions involving the present inventors, the content of n-heptane-insoluble, crystalline polypropylene was 75-96%, whereas, according to the present invention, it can be improved up to about 92-97%.

A second attainable effectiveness of the present invention consists in that the form of propylene polymers can be particularly improved. According to the above-mentioned previous methods of the inventions involving the present inventors, particles of ethylene polymers had a good form and their bulk density(BD) amounted up to 0.45, but particles of propylene polymers often had a bad form and their BD was only 0.08-0.18, and yet the particles were not uniform. In the case of the present invention, BD of propylene polymers had amounted up to 0.35 and also the form of particles has been improved to a nearly spherical form.

A third attainable effectiveness of the present invention consists in that the yield of a-olefin polymers based on the solid product (II) can be sufficiently high; in particular in the case of propylene polymerization under normal polymerization conditions, it has amounted to 5 x 103 to 2 x 104 9 (polymer)/g (solid product (II)). Even when the removal of catalyst remaining in the resulting polymers, i.e. the deashing step, is omitted, polymers have no coloration can be obtained and also there are observed no bad effects such as degradation of physical properties of polymers, rusting of mould during moulding of polymers, etc.

A fourth effectiveness of the present invention which can be obtained consists in that transition metals are very effectively used, and in the case of a typical propylene polymerization, the polymer yield amounts to 1 x 1 - 5 x 1069 (polymer)/g (atom of transition metal).

The present invention will be further illustrated in more detail by way of Examples.

EXAMPLE 1 (1) Preparation of solid products (I) and (II) Eighty g of aluminum trichloride (anhydrous) and 58 g of magnesium hydroxide were reacted together under milling by means of a vibrating mill at 1 800C for 10 hours, and reaction occurred with accompaniment of evolution of hydrogen chloride gas. After completion of heating, the resulting reaction product was cooled in a nitrogen gas current to obtain a solid product (I).

100 Grams of this solid product (I) and 20 g of titanium tetrachloride as EA were introduced into a vibrating mill and reacted together under milling at 1 200C for 5 hours, and thereafter unreacted titanium tetrachloride was removed under reduced pressure, followed by cooling the resulting reaction product.

Further, 12.0 g of a complex of titanium tetrachloride with benzoic acid as ED (mol ratio: 1 the terms "mol ratio" will be hereinafter omitted) was added, and reaction was carried out under milling by means of a vibrating mill, at 400C for 120 hours, to obtain a solid product (II). The content of titanium atom in 1 g of the solid product (II) was 19.5 mg.

(2) Production of propylene polymer Into a 1.5 1 capacity stainless steel reactor purged with nitrogen gas were introduced 1 l of nhexane, 480 mg of triisobutyialuminum and 12 mg of the solid product (II) obtained in the abovementioned item (1), and propylene was polymerized with 75 ml of hydrogen under a propylene partial pressure of 12 kg/cm2G, at 600C for 5 hours. After completion of polymerization, the solvent was removed by vaporization to obtain a polymer. Five g of this polymer was subjected to extraction with 50 ml of n-heptane by means of Soxhlet extractor at the boiling point of n-heptane (980C). The resulting n heptane-soluble was rendered atactic polypropylene and the remainder was rendered isotactic polypropylene.Isotactic index was sought as follows; Amount of isotactic polymer Isotactic index = - x 100 Total amount of polymer The resulting polymer had a BD of 0.35 and was much improved in the form. The results are shown in Table 1 collectively together with those of other Examples.

EXAMPLE 2 Into a 785 ml capacity ball mill of 100 mm in diameter (made of SUS 304) containing 80 stainless steel balls of 10 mm in diameter were introduced 20 g of solid product (I) obtained in Example 1, 3 g of silicon tetrachloride as Eats, and 4.0 g of ethyl cinnamate as ED, arid reaction was carried out under milling at 400C for 75 hours. After completion of the reaction, unreacted materials were removed under reduced pressure, and then 80 g of titanium tetrachloride as EA2 was introduced, and further, reaction was carried out under milling at 80CC for 40 hours. After completion of the reaction, the reaction product was separated by filtration in a dry box purged with nitrogen, followed by three times washing with 1 50 ml of n-hexane and then drying to obtain solid product (II).

Employing this solid product (II), propylene was polymerized as in Example 1. The results are shown in Table 1.

EXAMPLE 3 A complex obtained by reacting 3 g of aluminum trichloride with 1.7 g of dimethylpolysiloxane as EDt with stirring was introduced into a ball mill, and further 20 g of solid product (I) same as that of Example 1 was introduced, and reaction was carried out under milling at 300C for 48 hours. Thereafter 8 g of a complex of titanium tetrachloride as EA2 with tetrahydrofuran as ED2 (1 :2) was added, and reaction was carried out under milling at 500C for 60 hours to obtain solid product (II). The results are shown in Table 1.

EXAMPLE 4 Eighty g of aluminum trichloride (anhydrous) and 30 g of magnesium oxide were reacted together under milling in a ball mill at 1200C for 48 hours to obtain solid product (1).

Twenty g of this solid product (I) and 5 g of a complex of titanium tetrachloride as EA with ethyl phenylacetate as ED (1:1) were reacted together under milling in a vibrating mill at room temperature (200C) for 30 minutes. The resulting reaction product was suspended in a solution of 1 80 g of titanium tetrachloride in 50 ml of n-heptane, and reaction was carried out at 1000C for 4 hours. After completion of the reaction, the reaction product was separated by filtration in a dry box, followed by three times washings each with 1 50 ml of n-hexane and then drying to obtain solid product (II).

Employing this solid product (II), propylene was polymerized as in Example 1. The results are shown in Table 1.

EXAMPLE 5 40 Grams of a material obtained by heating 60 g of aluminium trichloride (anhydrous) and 20 g of hydrotalicite (Mg6al2(0H)";CO3-4H20) at 1000C for 2 hours was milled and reacted by means of a vibrating mill at 2500C for one hour to obtain a solid product (I).

Twenty ml of methylhydrogen polysiloxane as ED1 and 50 g of the above-mentioned solid product (I) were introduced into 200 ml of n-hexane, and reacted at 400C for one hour, followed by separation by filtration, washing with n-hexane and drying. Twenty g of this dried solid, 3 g of methyl toluylate as ED2 and 6 g of titanium tetrachloride as EA were introduced into a ball mill, and milled and reacted at 800C, for 20 hours, and then unreacted materials were removed while maintaining them under reduced pressure at 800C for 2 hours to obtain a solid product (II).

Employing this solid product (II), propylene was polymerized as in Example 1. The results are shown in Table 1.

EXAMPLE 6 Sixty g of iron trichloride (anhydrous) and 70 g of aluminum magnesium oxide (MgAI2t)4) were reacted in a vibrating mill at 3200C for 5 hours to obtain a solid product (I).

To a suspension of 20 g of this solid product (I) in 1 80 ml of toluene was added 10 g of ethanol as EDt, and reaction was carried out at 300Cforone hour. Thereafter 150 ml oftoluene was added and decantation procedure was twice repeated to render the total amount 180 ml. Eight g of benzophenone as ED2 was added, and reaction-was carried out at 600C for 30 minutes, followed by decantation, addition of 150 ml of toluene, decantation and rendering the total amount 60 ml. Thereafter, 100 ml of titanium tetrachloride as EA and 20 ml of n-butyl ether as ED3 were added and reaction was carried out at 1 300C for one hour, followed by separation by filtration, washing with n-hexane and drying to obtain a solid product (II).

Employing this solid product (II), propylene was polymerized as in Example 1. The results are shown in Table 1.

EXAMPLE 7 Eighty g of aluminum trichloride (anhydrous) and 65 g of magnesium chloride (hexahydrate) (MgCI2,6H20) were reacted together under milling in a vibrating mill at 800C for 20 hours to obtain a solid product (I).

To 20 g of this solid product (I) was added 3 g of n-butyl ether (ED,) and reaction was carried out in a vibrating mill at 400C for 30 minutes, and then 2 g of benzoic acid (ED2) was added to further react them in a vibrating mill at 600C for 30 minutes. The resulting reaction product was suspended in a mixture liquid of 120 g of titanium tetrachloride and 30 ml of n-hexane, and reaction was carried out at 750C for 3 hours. After completion of the reaction, unreacted materials were distilled off under reduced pressure to obtain a solid product (II).

Employing this solid product (II), propylene was polymerized as in Example 1. The results are shown in Table 1.

COMPARATIVE EXAMPLE 1 Example 1 was repeated except that the solid product (I) was reacted with titanium tetrachloride, not in two divided portions in Example 1, but at the same time.

Namely, 100 g of the solid product (I) obtained in Example 1, 20 g of titanium tetrachloride and 12 g of a complex of titanium tetrachloride with ethyl benzoate (1:1) were mixed together at the same time, and milled and reacted in a vibrating mill at 1 200C for 5 hours, and further reacted under milling at 400C for 120 hours, followed by removing unreacted titanium tetrachloride under reduced pressure to obtain a solid product (II). Employing this solid product (II), propylene was polymerized as in Example 1. The results are shown in Table 1. As seen from this Table, any of the polymer yield, isotactic index and BD were much inferior to those of Example 1.

COMPARATIVE EXAMPLE 2 Example 6 was repeated except that the solid product (I) was added to and reacted with three kinds of ED, not in three divided portions in Example 6, but at the same time.

Namely, to a suspension of the same solid product (I) as obtained in Example 6 in 180 ml of toluene were at the same time added 10 g of ethanol, 8 g of benzophenone, 100 ml of titanium tetrachloride and 20 ml of di-n-butyl ether, and reaction was carried out at 300C for one hour, further at 600C for 30 minutes, and then at 1 300C for one hour, followed by separation by filtration, washing with n-hexane and drying to obtain a solid product (II).

Propylene was polymerized as in Example 6 except that this solid product (Il) was employed. The results are shown in Table 1. As apparent from the Table, the results of this case, too, were much inferior to those of Example 6.

EXAMPLE 8 Employing the solid product (II) obtained in Example 1, propylene-ethylene copolymerization was carried out.

Ten mg of the same solid product (II) as obtained in Example 1, 420 mg of triethylaluminum, and 80 ml of hydrogen were introduced into a polymerization vessel, and polymerization was carried out at 600C for 4 hours, feeding ethylene 8 times at intervals of 30 minutes, each time in an amount of ethylene of 10 g, and under a propylene partial pressure of 10 kg/cm2G. After the reaction, the same procedure as in Example 1 was carried out to obtain a propylene-ethylene copolymer. The polymer yield per g of solid product (II) was 20,800 g (polymer) and the isotactic index was 92.0.

EXAMPLE 9 Propylene-butene-1 copolymerization was carried out as in Example 8, except that 20 g of butene-1 was substituted for ethylene. The polymer yield per g of solid product (II) was 20,300 g (polymer). The isotactic index was 91.0.

EXAMPLE 10 Employing the solid product (II) obtained in Example 2, ethylene was polymerized.

Employing 8 mg of solid product (II) obtained in Example 2 and 480 mg of triisobutylaiuminum, polymerization reaction was carried out at 850C for 5 hours under a hydrogen partial pressure of 5 kg/cm2G and an ethylene partial pressure of 5 kg/cm2G. After completion of the reaction, polymer was obtained as in Example 1. The polymer was 18,800 g (polymer)/g (solid product liy)). BD: 0.40. Ml: 6.5.

EXAMPLE 11 Employing the solid product (II) obtained in Example 3, butene-1 was polymerized.

Employing 20 g of solid product (II) obtained in Example 3 and 380 mg of triethylaluminum, 480 g of butene-1 was continuously fed at 700C for 4 hours, and then further, reaction was carried out for 2 hours. After completion of the reaction, solvent was distilled off to obtain 2.73 g of polybutene. The polymer yield was 13,650 g (polymer)/g (solid product (II)).

EXAMPLE 12 133 Grams of aluminum trichloride (anhydrous) and 40 g of magnesium oxide were milled in a ball mill for 24 hours, and then heated at 1 200C for 2 hours, followed by cooling and further milling for 10 hours to obtain a solid product (I).

Forty g of this solid product (I) and a reaction product obtained in advance by mixing and reacting 1 2 g of ethyl benzoate (ED) with 4.5 g of silicon tetrachloride (EA,) at room temperature (200 C) were milled and reacted in a ball mill at 350C for 48 hours. Twenty g of the resulting powder was suspended in 1 80 g of titanium tetrachloride (EA2), and reaction was carried out at 800C for 2 hours, followed by removing the supernatant liquid by decantation, further adding 180 g of titanium tetrachloride, reaction at 800C for one hour and removing the supernatant liquid by decantation. Procedure of adding 1 50 ml of n-hexane and removal by decantation was twice repeated, followed by separation by filtration in a dry box and drying to obtain a solid product (II).

Employing this solid product (II), propylene was polymerized as in Example 1. The results are shown in Table 1.

EXAMPLE 13 Twenty g of the solid product (I) obtained in the same procedure as in Example 12, 2 g of cumyl alcohol (ED,) and 5 g of ethyl benzoate (ED2) were milled and reacted in a ball mill at 400C for 48 hours, and then 9 g of silicon tetrachloride (EA) was added, and further, milling and reaction were carried out for 24 hours to obtain a powder. Twenty g of this powder was then suspended in 240 g of titanium tetrachloride (EA2), and reacted at 1000C for 2 hours, followed by removing the supernatant liquid by decantation. 150 MI of n-hexane was added and removal of the supernatant liquid was twice repeated, followed by separation by filtration and drying to obtain a solid product (II).

Employing this solid product (II), propylene was polymerized as in Example 1. The results are shown in Table 1.

EXAMPLE 14 Forty g of the solid product (I) obtained in the same procedure as in Example 12 and 12 g of methyl benzoate (ED1) were milled and reacted in a ball mill at 300C for 24 hours, and then 15 g of silicon tetrachloride (EA,) was added, and further, reaction was carried out for 48 hours to obtain a powder. Twenty g of this powder was suspended in 350 g of titanium tetrachloride (EA2), and then reaction was carried out at 800C for 2 hours, followed by removing the supernatant liquid by decantation, adding 200 ml of tetrachloroethylene and decantation. Further 200 ml of n-hexane was added, and decantation was twice repeated, followed by distilling off n-hexane under reduced pressure to obtain a solid product (II).

Employing this solid product (II), propylene was polymerized as in Example 1. The results are shown in Table 1.

EXAMPLE 15 Forty g of the solid product (I) obtained in the same procedure as in Example 12 and 16 g of propyl benzoate (ED1) were milled and reacted in a ball mill at 450C for 48 hours. Twenty g of the resulting powder was suspended in 190 g of titanium tetrachloride (EA), and then reaction was carried out at 700C for 4 hours, followed by separation by filtration to separate and remove the reaction liquid.

The resulting solid was again suspended in 220 g of titanium tetrachloride, and then reaction was carried out at 900C for one hour, followed by removing the reaction. liquid by decantation. 250 MI of nhexane was added and decantation was twice repeated, followed by distilling off n-hexane under reduced pressure to obtain a solid product (II).

Employing this solid product (II), propylene was polymerized as in Example 1. The results are shown in Table 1.

EXAMPLE 16 Twelve mg of the solid product (II) obtained in Example 12 and 480 mg of triisobutylaluminum were suspended in 500 g of liquefied propylene in the absence of solvent, and 90 ml of hydrogen was introduced. Polymerization reaction was carried out art a polymerization temperature of 650C for 3 hours under a pressure of 26.5 kg/cm2G. After completion of the polymerization reaction, remaining propylene was removed to obtain 1 58 g of propylene polymer. The polymer yield per g of solid product (II) was 13,170 g, and the polymer yield per g of titanium atom was 0.69 x 106 g. Isotactic index: 92.0, BD of polymer: 0.30 and MFR: 4.8.

TABLE 1

Ti atom Ti atom Polymer yield (g) content in solid per g of product solid / MFR (Il) product per g of Isotactic BD 2.16 kg (mg/g) (rl) Ti atom index (g/cm ) 230"C Example 1 19.5 20.300 1.04x106 96.0 0.35 7.5 2 2 20.5 21,400 1.04x106 96.0 0.33 6.8 3 3 35.0 17,300 0.49x106 96.5 0.35 4.9 ., 4 16.8 17,200 1.02x106 97.0 0.32 4.2 5 5 24.5 14,300 0.58x106 96.0 0.30 3.8 6 6 22.3 11,300 0.50x106 95.8 0.31 3.4 7 7 23.4 12,300 0.53X105 95.2 0,30 4.8.

Compar. ex. 1 20.2 2,540 0.13x105 85.0 0.08 4.1 2 2 25.0 1,050 0.04x106 75.0 0.06 4.5 Example 12 19.0 14,500 0.76x106 92.1 0.31 4.9 13 13 22.0 ' 16,200 0.74x106 93.0 0.32 4.8 14 14 16.0 13,300 0.53x106 93.1 0.30 3.9 15 15 18.0 14,100 0.78x106 92.1 0.30 4.1 16 16 19.0 13,170 0.69x106 92.0 0.30 4.8

Claims (15)

1. A method for preparing as a solid product (II) a component for an a-olefin polymerization catalyst, the method comprising reacting a trivalent metal halide with a hydroxide, oxide or carbonate of a divalent metal, a double compound containing any such compound, or a hydrate of a divalent metal compound, thereby to form a solid product (I); and reacting the solid product (I) with an electron donor comprising one or more electron donor compounds, and with an electron acceptor comprising titanium tetrachloride and optionally one or more other electron acceptor compounds, thereby to form a solid product (II), the electron donor and/or the electron acceptor being reacted with the solid product (I) in at least two separate portions.

2. A method according to claim 1 , comprising reacting the electron donor in two portions.

3. A method according to claim 1 or claim 2, comprising reacting the electron acceptor in two portions.

4. A method according to claim 1, 2 or 3, wherein said trivalent metal halide is aluminium trichloride.

5. A method according to any preceding claim, wherein the divalent metal compound is MgO, Mg(OH)2 or MgCO3.

6. A method according tp any preceding claim, wherein the electron donor is one or more esters.

7. A method according to any preceding claim, wherein the electron acceptor comprises two electron acceptor compounds.

8. A method according to any preceding claim, wherein the eiectron acceptor includes SiCI4.

9. A method according to any preceding claim, wherein the a-olefin is or includes propylene.

10. A method for preparing as a solid component (II) a component for an a-polymerization catalyst, the method being substantially as hereinbefore described in any of the examples herein.

11. A catalyst component when prepared by a method as claimed in any preceding claim.

12. A method for producing an a-olefin polymerization catalyst which comprises reacting a catalyst component as claimed in claim 11 with an organoaluminium compound.

1 3. An a-olefin polymerization catalyst when produced by a method as claimed in claim 12.

14. A method for polymerizing an a-olefin which employs a catalyst as claimed in claim 13.

15. Poly (c-olefin) manufactured by a method as claimed in claim 14.