GB1564460A - Olefin polymerisation catalyst and polymerisation process - Google Patents

Description

(54) OLEFIN POLYMERISATION CATALYST AND POLYMERISATION PROCESS (71) We, MITSUI PETROCHEMI CAL INDUSTRIES LTD, a Japanese Body Corporate of 2-5, 3-chome, Kasumigaseki, Chiyoda-ku, Tokyo, Japan, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method bywhich it is to be performed, to be particularly described in and by the following statement:- This invention relates to a process which can afford highly stereoregular polymers or copolymers in high yields when applied to the polymerization or copolymerization of aolefins, especially those having at least 3 carbon atoms.

Many prior suggestions have been known for the preparation of highly stereoregular polymers or copolymers by using a solid complex titanium component at least containing magnesium, titanium and halogen, preferably treated with an electron donor, as a titanium catalyst component which constitutes a catalyst for the polymerization or copolymerization of a-olefins containing at least 3 carbon atoms (for example, German Laid-Open Patent Publication Nos. 2,153,520, 2,230,672 and 2,553,104).

These prior suggestions teach combinations of specific catalyst-forming components, and combinations of catalyst-forming procedures and the catalyst-forming components as essential conditions. As is well known, the characteristics of catalysts containing a solid complex titanium component of this type vary greatly according to differences in the combination of the above catalyst-forming components, the combinations of the catalystforming procedures, and the combinations of these conditions. When catalyst-forming components and/or catalyst-forming procedures which are essential in a given combination of conditions are used in a different combination of conditions, it is quite impossible to anticipate whether similar results will be obtainable. Frequently, the result is a catalyst having quite poor properties.

The aforesaid solid complex titanium component at least containing magnesium, titanium and halogen is no exception. If in the polymerization or copolymerization of aolefins containing at least 3 carbon atoms in the presence of hydrogen using a catalyst composed of the aforesaid titanium component and an organometallic compound of a metal of Groups I to IV of the periodic table, a catalyst composed of a titanium trichloride component obtained by reducing titanium tetrachloride with metallic aluminum, hydrogen, or an organoaluminum compound is used together with a donor known to have an effect of inhibiting the formation of an amorphous polymer, the effect varies unpredictably according to the donor used.

The present invention provides a catalyst composition suitable for use in preparing olefin polymers or copolymers, which comprises: (a) a solid complex titanium component at least containing magnesium, titanium, halogen and an electron donor; (b) an organometallic compound of a metal of Groups I to III of the Periodic Table; and (c) an organic acid anhydride.

The invention also provides a process for preparing olefin polymers or copolymers, which process comprises polymerizing or copolymerizing at least one olefin in the presence of the catalyst composition of the invention.

The process of the invention can produce highly stereoregular polymers in high yields while advantageously overcoming the problem of the formation of an amorphous polymer associated with the use of a catalyst composed of (a) a solid complex titanium component at least containing magnesium, titanium and halogen, and (b) an organometallic compound of a metal of Groups I to III of the Periodic Table.

The use of the organic acid anhydride (c), preferably a carboxylic acid anhydride including an aromatic carboxylic acid anhydride, together with (a) and (b) affords a catalyst which can overcome the above prob lem and has high activity and superior reproducibility of its properties.

The solid complex titanium component (a) preferably is a solid complex which has a halogen/titanium atomic ratio of more than 4:1, and does not substantially permit the liberation of a titanium compound by washing with hexane at room temperature. The chemical structure of this solid complex is not known, but presumably, the magnesium atom and the titanium atom are bonded firmly by, for example, having the halogen in common. The solid complex may, depending upon the method of preparation, contain other metal atoms such as aluminum, silicon, tin, boron, germanium, calcium and zinc. It may further contain an organic or inorganic inert diluent, such as LiCl, CaCO,, BaCI2, NaCO,, SrCl2, B2O3, Na2SO4, Al2O3, SiO2, TiO2, NaB4O7, Ca,(PO4)2, CaSO4, Al2(SO4),, Cacti2, ZnCl2, polyethylene, polypropylene, and polystyrene. In preferred examples of the solid complex titanium component (a), the halogen/titanium atomic ratio is above 4:1, more preferably at least 5:1, especially at least 8:1, and the magnesium/ titanium atomic ratio is at least 3:1, more preferably 5:1 to 50:1, and the electron donor/titanium molar ratio is 0.2:1 to 6:1, more preferably 0.4:1 to 3:1, especially 0.8:1 to 2:1. Furthermore, the specific surface area of the solid is at least 3 m2/g, preferably at least 40 m2/g, and more preferably at least 100 m2/g. It is also desirable that the X-ray spectrum of the solid complex (a) should show amorphous character irrespective of the starting magnesium compound, or it is in a more amorphous state than ordinary commercially available grades of magnesium dihalide.

The solid complex titanium component (a) can be formed by various means, and most commonly, a magnesium compound and a titanium compound are contacted while at least one of them contains halogen, and the product is treated with an electron donor.

Various suggestions have been known for the preparation of such component (a), and can be used in this invention. Some of such suggestions are disclosed in German Laid-Open Patent Publications Nos. 2,230,672, 2,504,036, 2,553,104 and 2,605,922 and Japanese Laid-Open Patent Publications Nos.

28189/76, 127185/76, 136625/76 and 87486/77.

Typical methods disclosed in these documents involve the reaction of at least a magnesium compound (or metallic magnesium), an electron donor and a titanium compound.

Examples of the electron donor are oxygencoining electron donors such as water, alcc phenols, ketones, aldehydes, carb oxyliet 'ds, esters, ethers and acid amides, and ni ontaining electron donors such as ammo es, nitriles and isocyanates.

R n P r i include alcohols containing 1 to 18 carbon atoms such as methanol, ethanol, propanol, pentanol, hexanol, octanol, dodecanol, octadecyl alcohol, benzyl alcohol, phenylethyl alcohol, cumyl alcohol, and isopropyl benzyl alcohol; phenols containing 6 to 15 carbon atoms which may contain a lower alkyl group, such as phenol, cresol, xylenol, ethyl phenol, propyl phenol, cumyl phenol, and naphthol; ketones containing 3 to 15 carbon atoms such as acetone, methyl ethyl ketone, methyl isobutyl ketone, acetophenone and benzophenone; aldehydes containing 2 to 15 carbon atoms such as acetaldehyde, propionaldehyde, octyl aldehyde, benzaldehyde, tolualdehyde and naphthoaldehyde; organic acid esters containing 2 to 18 carbon atoms such as methyl formate, methyl acetate, ethyl acetate, vinyl acetate, propyl acetate, octyl acetate, cyclohexyl acetate, ethyl propionate, methyl butyrate, ethyl valerate, methyl chloroacetate, ethyl dichloroacetate, methyl methacrylate, ethyl crotonate, ethyl cyclohexanecarboxylate, methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, octyl benzoate, cyclohexyl benzoate, phenyl benzoate, benzyl ben zoate, methyl toluate, ethyl toluate, amyl toluate, ethyl ethylbenzoate, methyl anisate, ethyl anisate, ethyl ethoxybenzoate, e-butyro- lactone, B-valerolactone, coumarin, phthalide and ethylene carbonate; acid halides contain ing 2 to 15 carbon atoms such as acetyl chlor ide, benzyl chloride, toluic acid chloride, and anisic acid chloride; ethers containing 2 to 20 carbon atoms such as methyl ether, ethyl ether, isopropyl ether, butyl ether, amyl ether, tetrahydrofuran, anisole, and diphenyl ether; acid amides such as acetamide, benzamide and toluamide; amines such as methylamine, ethylamine, diethylamine, tributylamine, piperidine, tribenzylamine, aniline, pyridine, picoline and tetramethylethylene diamine; nitriles such as acetonitrile, benzonitrile and tolunitrile; and compounds of aluminum, silicon and tin which contain the aforesaid functional groups in the molecule. These elec tron donors can be used as a mixture of two or more.

Suitable magnesium compounds used for the formation of the solid complex titanium compound (a) are those containing halogen and/or organic groups. Specific examples of such magnesium compounds include magne sium dihalides, magnesium alkoxyhalides, magnesium aryloxyhalides, magnesium hydroxyhalides, magnesium dialkoxides, magnesium diaryloxides, magnesium alkoxyaryloxides, magnesium acryloxyhalides, magnesium alkylhalides, magnesium arylhalides, magnesium dialkyl compounds, magnesium diaryl compounds, and magnesium alkylalkoxides. They may be present in the form of adducts with the aforesaid electron donors.

Or they may be double compounds contain con, germanium, zinc or boron. For example, they may be double compounds of halides, alkyl compounds, alkoxyhalides, aryloxyhalides, alkoxides and aryloxides of metals such as aluminum, and the above-exemplified magnesium compounds. Or they may be double compounds in which phosphorus or boron is bonded to magnesium metal through oxygen. These magnesium compounds may be a mixture of two or more. Usually, the above-exemplified compounds can be expressed by simple chemical formulae, but sometimes, according to the method of preparation of the magnesium compounds, they cannot be expressed by simple formulae. They are usually regarded as mixtures of the aforesaid compounds. For example, compounds obtained by a method which comprises react ing magnesium metal with an alcohol or phenol in the presence of a halosilane, phos phorus oxychloride, or thionyl chloride, and a method which comprises pyrolyzing Grig nard reagents, or decomposing them with compounds having a hydroxyl group, a car bonyl group, an ester linkage, or an ether linkage are considered to be mixtures of vari ous compounds according to the amounts of the reagents or the degree of reaction. These compounds can of course be used in this invention.

Various methods for producing the mag nesium compounds exemplified hereinabove are known, and products of any of these methods can be used in this invention. Also, prior to use, the magnesium compound may be treated, for example, by a method which comprises dissolving it singly or together with another metal compound in ether or acetone, and then evaporating the solvent or putting the solution into an inert solvent thereby to separate the solid. A method can also be em ployed which involves pre-pulverizing mechanically at least one magnesium com pound with or without another metal compound.

Preferred among these magnesium com pounds are magnesium dihalides, aryloxy halides and aryloxides, and double compounds of these with aluminum or silicon. More spe cifically, they are MgCl2, MgBr2, MgI2, MgF2, MgCl(OC6H3), Mg(OC6H5)2, MgCl(OC6H4-2-CH3), Mg(OC6H4-2-CH3)2, (MgCl2)x[Al(OR)nCl3-n]y, and (Mga,), [SI(OR),,,CI,~,,,] ,.

In these formulae, R is a hydrocarbon group such as an alkyl or aryl group, m or n R groups are the same or different, 0#n#3, O(m4, and x and y are positive numbers.

MgCl2 and its complexes or double com pounds are especially preferred.

Suitable titanium compounds used for the formation of the solid complex titanium com pound (a) are tetravalent titanium compounds of the formula Ti(OR)gX.1~e wherein R is a hydrocarbon group, preferably an alkyl group containing 1 to 6 carbon atoms, X is a halogen atom, and O~g < 4. Examples of the titanium compounds are titanium tetrahalides such as TiCl4, TiBr4 or TiI4; alkoxytitanium trihalides such as Ti(OCH3)Cl3, Ti(OC2H5)Cl3, Ti(O n-C4H9). Cl3, Ti(OC2H5)Br3, and Ti(O iso-C4H9)Br3; alkoxytitanium dihalides such as Ti(OCH,)2Cl2, Ti(OC2H, )2Cl2, Ti(O n-C4H9)2. Cl2, and Ti(OC,H)2Br2; trialkoxytitanium monohalides such as Ti(OCH3)3Cl, Ti(OC2H5)3Cl, Ti(O n-C4H9)3Cl and Ti(OC2H5)3. Br; and tetraalkoxytitanium such as Ti(OCH3)4, Ti(OC2H,)4, and Ti(O n-C4HD)4. Of these, the titanium tetrahalides are preferred, and especially preferred is titanium tetrachloride.

The solid complex titanium compound (a) is also derived from an electron donor. Examples of the electron donor are esters, ethers, ketones, tertiary amines, acid halides, and acid anhydrides, which do not contain active hydrogen. Organic acid esters and ethers are especially preferred, and most preferred are aromatic carboxylic acid esters and alkylcontaining ethers. Typical examples of suitable aromatic carboxylic acid esters include lower alkyl esters such as lower alkyl esters of benzoic acid, and lower alkyl esters of alkoxy benzoic acid. The term "lower" means the possession of 1 to 4 carbon atoms. Those having 1 or 2 carbon atoms are especially preferred. Suitable alkyl-containing ethers are those containing 4 to 20 carbon atoms such as diisoamyl ether and dibutyl ether.

There are various examples of reacting the magnesium compound (or metallic magnesium), the electron donor and the titanium compound, and typical ones are described below.

[I] Method involving reacting the magnesium compound with the electron donor and then reacting the reaction products with the titanium compound: (I-a) Method [I] with the copulverization of the magnesium compound and the electron donor: The electron donor added at the time of copulverization needs not to be in the free state, and may be present in the form of an adduct with the magnesium compound. At the time of copulverization, additional ingredients, which may be included in the complex titanium component (a), for example, the aforesaid organic or inorganic inert diluent, a halogenating agent such as a halogen compound of silicon, a silicon compound such as polysiloxane, and a compound of aluminum, germanium or tin, or a part of the titanium compound may be present together.

Or the electron donor may be present in the form of an adduct (complex compound) with such a compound. The amount of the electron donor used is preferably 0.005 to 10 moles, more preferably 0.01 to 1 mole, per mole of the magnesium compound.

The copulverization may be carried out by using ordinary devices such as a rotary ban mill, a vibratory ball mill, and an impact mill. If the rotary ball mill is used, and 100 stainless steel (SUS 32) balls having a diameter of 15 mm are accomodated in a ball mill cylinder having an inner capacity of 800 ml and an inside diameter of 100 mm and made of stainless steel (SUS 32) and 20 to 40 g of the materials to be treated are put into it, it is advisable to perform the pulverization for at least 24 hours, preferably at least 48 hours at a rotating speed of 125 rpm.

The temperature of the pulverization treatment is usually room temperature to about 1000 C.

The copulverized product can also be reacted with the titanium compound by copulverizing means. However, it is preferred to suspend the copulverized product in at least about 0.05 mole, preferably about 0.1 to about 50 moles, per mole of the magnesium compound, of a liquid titanium compound with or without using an inert solvent. The reaction temperature is from room temperature to 200"C, and the reaction time is from 5 minutes to 5 hours. The reaction can of course be performed under conditions outside these specified ranges. After the reaction, the reaction mixture is hot-filtered at a high temperature of, say, about 60 to 1500C to isolate the product which is then well washed with an inert solvent before use in polymerization.

(I-b) Method [I] without the copulverization of the magnesium compound and the electron donor: Usually, the magnesium compound is reacted with the electron donor in an inert solvent, or the magnesium compound is dissolved or suspended in the liquid electron donor for reaction. It is possible to employ an embodiment in which magnesium metal is used as a starting material, and reacted with the electron donor while forming a magnesium compound.

The amount of the electron donor used is preferably 0.01 to 10 moles, more preferably 0.05 to 6 moles, per mole of the magnesium compound. The reaction proceeds sufficiently at a reaction temperature of from room temperature to 2000C for 5 minutes to 5 hours.

After the reaction, the reaction mixture was filtered or evaporated, and washed with an inert solvent to isolate the product. The reaction of the reaction product with the titanium compound can be performed in the same was as described in (I-a).

(I-c) Method which comprises reacting the reaction product of the magnesium compound and the electron donor with a compound selected from organoaluminum compounds, silicon compounds and tin compounds, and then reacting the resulting product further with the titanium compound: This method is a special embodiment of the method (I-b). Generally, complexes obtained by the method (I-a) have superior properties, but some of complexes obtained by the method (I-b) have inferior properties to those obtained by method (I-a). The properties of such complexes can be very effectively improved by the performance of method (I-c) in which the organoaluminum compound, silicon compound or tin compound is reacted prior to the reaction with the titanium compound.

Examples of the organoaluminum compounds that can be used in this method are trialkyl aluminums, dialkyl aluminum hydrides, dialkyl aluminum halides, alkyl aluminum sesquihalides, alkyl aluminum dihalides, dialkyl aluminum alkoxides or phenoxides, alkyl aluminum alkoxy halides or phenoxyhalides, and mixtures of these. Of these, the dialkyl aluminum halides, alkyl aluminum sesquihalides, alkyl aluminum dihalides, and mixtures of these are preferred.

Specific examples of these include triethyl aluminum, triisobutyl aluminum, diethyl aluminum hydride, dibutyl aluminum hydride, diethyl aluminum chloride, diisobutyl aluminum bromide, ethyl aluminum sesquichloride, diethyl aluminum ethoxide, ethyl aluminum ethoxy chloride, ethyl aluminum dichloride, and butyl aluminum dichloride.

The silicon or tin compounds, for example silicon or tin halogen compounds or organic compounds, are compounds containing at least one halogen or hydrocarbon group directly bonded to silicon or tin, and may further contain hydrogen, an alkoxy group, a phenoxy group, or the like. Specific examples include, silicon tetrahalides, tetraalkyl silicons, silicon alkyl halides, silicon alkylhydrides, tin tetrahalides, tin dihalides, tin alkylhalides, and tin hydride halides. Of these, silicon tetrachloride and tin tetrachloride are preferred.

The reaction between the magnesium compound and the electron donor can be performed by the method (I-b). The reaction of the resulting reaction product between the magnesium compound and the electron donor with the organoaluminum compound, silicon compound or tin compound may be carried out in an inert solvent. Such a compound is used in an amount of preferably 0.1 to 20 moles, more preferably 0.5 to 10 moles, per mole of the magnesium compound. The reaction is carried out preferably at a temperature of from room temperature to 100"C for 5 minutes to 5 hours. After the reaction, the reaction mixture is preferably well washed with an inert solvent, and then reacted with the titanium compound. The reaction of this reaction product with the titanium compound can be performed in accordance with the method described in (I-a).

[II] Method which comprises simultane ously reacting the magnesium compound, the electron donor and the titanium compound.

[III] Method which comprises reacting the reaction product between the titanium compound and the electron donor with the magnesium compound.

The reactions in the methods [II] and [III] are preferably performed by copulver ization. The pulverization conditions and the proportions of the raw materials are the same as set forth under method [I]. In these methods, however, it is not preferred to use a large quantity of the titanium compound.

The amount of the titanium compound is pre ferably 0.01 to 1 mole per mole of the magnesium compound.

The above methods are typical methods, and many modifications are possible as shown below.

(1) Method [I] in which the electron donor is caused to be present when reacting the titanium compound.

(2) A method in which the organic or inorganic inert diluent and the silicon, aluminum, germanium or tin compound are caused to be present during the reaction; a method in which these compounds are caused to act before the reaction; a method in which these compounds are caused to act between the reactions; a method in which these compounds are caused to act after the reaction. A typical example of methods is the method (I-c).

These reagents can be used at desired points in the above methods.

For example, (2-a) Method in which a halogenating agent such as SICK4 is caused to act on the compound obtained by methods [I], [II] and [III].

(3) Method in which the titanium compound is caused to act two or more times:- (3-a) The method in which the titanium compound and the electron donor are reacted with the reaction product obtained by any of the methods [I] to [III].

(3-b) The method in which the titanium compound, the organoaluminum compound and the electron donor are reacted with the reaction product of any one of these methods [I] to [III].

A number of other modifications can be made by changing the order of addition of reaction agents, or by carrying out a plurality of reactions, or by using additional reaction agents. In any of such methods, it is desirable that the halogen, titanium and magnesium in the complex (a), the proportion of the electron donor, the surface area of the complex (a) and the X-ray spectrum of the catalyst be within the above ranges or in the abovementioned conditions.

In the present invention, polymerization or copolymerization is carried out in the presence of a catalyst composed of the solid complex titanium component (a) at least containing magnesium, titanium and halogen and preferably being treated with an electron donor, (b) an organometallic compound of a metal of Groups I to III of the periodic table, and (c) an organic acid anhydride.

The organometallic compound (b) has a hydrocarbon group directly bonded to the metal, and includes, for example, alkyl aluminum compounds, alkyl aluminum alkoxides, alkyl aluminum hydrides, alkyl aluminum halides, dialkyl zincs, and dialkyl magnesiums. Preferred among them are the organoaluminum compounds. Specific examples of the organoaluminum compounds are trialkyl or trialkenyl aluminums such as A1(C2H5)3, Al(CH,)a, Al(CaH,),, A1(C,H,), and Al(C12H2s)3; alkyl aluminum compounds having such a structure that many aluminum atoms are connected through oxygen or nitrogen atoms, such as (C2H,)2AlOAl(H5)2, (C4Hp)2AlOAl(C4Hg)2 and

dialkyl aluminum hydrides such as (C2H, ) 2 or (C4Hg)2AlH; dialkyl aluminum halides such as (C2Hs)2AlCl, (C2H, )2AlI or (C4Hg)2AlCl; and dialkyl alu- minum alkoxides or phenoxides such as (C2H5 )2Al(OC2H) and (C2H, )2Al(OCeH).

Of these, the trialkyl aluminums are most preferred.

Examples of the organic acid anhydride (c) include anhydrides of aliphatic monocarboxylic acids of 2 to 18 carbon atoms such as acetic anhydride, propionic anhydride, nbutyric anhydride, iso-butyric anhydride, monochloroacetic anhydride, trifluoroacetic anhydride, caproic anhydride, lauric anhydride and stearic anhydride; anhydrides of aliphatic polycarboxylic acids of 4 to 22 car-bon atoms such as succinic anhydride, maleic anhydride, glutaric anhydride, citraconic anhydride, itaconic anhydride, methylsuccinic anhydride, dimethylsuccinic anhydride, ethylsuccinic anhydride, butylsuccinic anhydride, octylsuccinic anhydride, stearylsuccinic anhydride, and methylglutaric anhydride; anhydrides of alicyclic carboxylic acids of 8 to 10 carbon atoms such as bicyclo[2.2.1] heptene-2,3-dicarboxylic anhydride or methylbi cyclo [2.2.1] heptene - 2,3 - dicarboxylic anhydride; and anhydrides of aromatic carboxylic acids of 9 to 15 carbon atoms such as acetobenzoic anhydride, acetotoluic anhydride, benzoic anhydride, toluic anhydride, phthalic anhydride, and trimellitic anhydride.

Of these, the aromatic carboxylic acid anhydrides are preferred. The aliphatic monocarboxylic acid anhydrides are next preferred although they tend to give somewhat low polymerization activity. These acid anhydrides can also be used as electron donors in the preparation of the solid complex titanium component (a).

These acid anhydrides may be used as addition reaction products or substitution reaction products with organometallic compound (b). The preferred method of using the acid anhydrides is to purge the polymerization system with an olefin monomer, add the acid anhydride and the organometallic compound (b), and then add the titanium catalyst component (complex) (a). It is possible to contact the acid anhydride with the organometallic compound outside the polymerization system, and then feed them into the polymerization system.

According to the process of this invention, the polymerisation of olefins such as ethylene, propylene, l-butene or 4-methyl-1-pentene can be advantageously carried out. The process can especially advantageously be applied to the polymerization of a-olefins containing at least 3 carbon atoms, copolymerization (random copolymerization, and block copolymerization) of these with each other, copolymerization of these with not more than 10 mole% of ethylene, and copolymerization of these with polyunsaturated compounds such as coniugated or non-coniugated dienes.

The polymerization can be carried out either in the liquid or vapor phase. When it is performed in the liquid phase, an inert solvent such as hexane, heptane or kerosene may be used as a reaction medium, but the olefin itself may serve as the reaction medium. In the case of the liquid-phase polymerization, the preferred concentration of the solid complex titanium component (a) in the polymerization system is 0.001 to 5 millimoles, preferably 0.001 to 0.5 millimole as titanium atom per liter of the solvent, and the preferred concentration of the organometallic compound is 0.1 to 50 millimoles as metal atom per liter of the solvent. In the case of the vapor phase polymerization, the solid titanium catalyst component (A) is used in an amount of 0.001 to 5 millimoles, preferably 0.001 to 1.0 millimole per liter of polymerization zone, more preferably 0.01 to 0.5 millimole per liter of polymerization zone, calculated as titanium atom. The organometallic compound (B) is used preferably in an amount of 0.01 to 50 millimoles per liter of polymerication zone calculated as metal atom.

The ratio of the organometallic component (b) to the solid complex titanium component (a) may be such that the ratio of the metallic atom in component (b) to the titanium atom in component (a) is preferably 1/1 to 1000/1, preferably 1/1 to 200/1. The amount of the acid anhydride component (c) is preferably 0.001to 1 mole, more preferably 0.01 to 1 mole, per metal atom of the organometallic compound (b).

Polymerization reactions of olefins in the presence of the catalyst of this invention can be performed in the same way as in the polymerization of olefins with ordinary Zieglertype catalysts. Specifically, the reaction is performed in the substantial absence of oxygen and water. When a suitable inert solvent such as an aliphatic hydrocarbon (e.g. hexane, heptane or kerosene) is used, the catalyst and an olefin and optionally a diolefin are charged into a reactor, and the polymerization is carried out. The polymerization temperature is usually 20 to 2000C, preferably 50 to 1500C.

Preferably, the polymerization is carried out at el moles of phthalic anhydride, and 0.03 millimole, calculated as titanium atom, of the component (a) were charged into the autoclave. The autoclave was sealed, and then, 250 ml of hydrogen was charged, and the temperature was raised. When the temperature of the polymerization system rose to 600 C, propylene was introduced into the autoclave and its polymerization was started at a total pressure of 8 kg/cm2. The polymerization was performed at 60"C for 6 hours. Then, the introduction of propylene was stopped, and the contents of the autoclave were cooled to room temperature. The resulting solid was collected by filtration, and dried to afford 335.7 g of polypropylene as a white powder. The polymer had a boiling n-heptane extraction residue of 94.9%, an apparent density of 0.31 g/ml, and a melt index of 2.7.

Concentrating the liquid layer afforded 13.4 g of a solvent-soluble polymer.

Example 2.

Commercially available anhydrous magnesium chloride (9.5 g; 0.1 mole) was suspended in 0.3 liter of kerosene, and at room temperature, 23.3 ml (0.4 mole) of ethanol and 14.3 ml (0.1 mole) of ethyl benzoate were added. The mixture was stirred for 1 hour. Then, 24.2 ml (0.2 mole) of diethyl aluminum chloride was added dropwise at room temperature, and stirred for 1 hour.

The solid portion of the reaction product was collected, washed fully with kerosene, and suspended in 0.3 liter of kerosene containing 30 ml of titanium tetrachloride. The reaction was performed at 80"C for 2 hours. After the reaction, the supernatant liquid was removed by decantation. The solid portion was fully washed with fresh kerosene to afford a solid complex titanium component (a) which contained 3.5% by weight of titanium atom, 59.3% by weight of chlorine atom, 19.3% by weight of magnesium atom, and 14.7% by weight of ethyl benzoate, and had a specific surface area of 175 m2/g.

Propylene was polymerized in the same way as in Example 1 except that 0.05 millimole, as titanium atom, of the component (a) was used. Polypropylene was obtained in an amount of 327.4 g as a white powder. The polymer had a boiling n-heptane extraction residue of 95.0% by weight, an apparent density of 0.32 g/ml and a melt index of 3.6.

Concentrating the liquid layer afforded 11.7 g of a solvent-soluble polymer.

Examples 3 to 8.

Propylene was polymerized in the same way as in Example 1 except that each of the acid anhydrides shown in Table 1 was used instead of the phthalic anhydride. The results are shown in Table 1.

TABLE 1

Catalyst component (c) Results of polymerization Amount of Amount of Extraction Apparent powdery poly- solvent-soluble residue of density of Melt index Amount propylene polymer the powder the powder of the Example Compound (millimoles) formed (g) formed (g) (%) (g/ml) powder 3 Acetic anhydride 1.5 211.7 8.7 94.8 0.30 6.0 4 Itaconic anhydride 1.4 275.6 11.6 89.4 0.31 5.3 5 Benzoic anhydride 1.6 298.3 10.2 95.0 0.30 8.6 6 Succinic anhydride 1.4 290.2 10.0 90.3 0.31 6.2 7 Toluic anhydride 1.5 329.5 12.5 95.1 0.29 5.4 8 Propionic anhydride 1.5 213.5 8.4 93.8 0.30 4.7 Example 9.

Commercially available Mg(OCH3)2 (8.6 g; 0.1 mole) was suspended in 0.3 liter of kerosene, and 10.6 ml (0.1 mole) of ocresol was added. The reaction was performed for 1 hour at 80 C. At the same temperature, 7.2 ml (0.05 mole) of ethyl benzoate was added, and the reaction was further carried out for 1 hour. The reaction mixture was cooled to 60 C, and 2.9 ml (0.025 mole) of SiCl4 was added dropwise over the course of 30 minutes, and the reaction was performed at 60 C for 1 hour. After cooling, the solid portion of the product was collected. It was fully washed with kerosene, and suspended in 300 ml of titanium tetrachloride and reacted at 130 C for 2 hours. After the reaction, the suspernatant liquid was removed by decantation. The solid portion was fully washed with fresh kerosene to afford a solid complex titanium component (a) which contained 4.1% by weight of titanium atom, 54% by weight of chloride atom, 16.7% by weight of magnesium atom, and 11.3% by weight of ethyl benzoate.

Propylene was polymerized in the same way as in Example 1. There was obtained 296.2 g of polypropylene as a white powder.

The polymer had a boiling n-heptane extraction residue of 95.1%, an apparent density of 0.30 g/ml and a melt index of 3.6.

Concentrating the liquid layer afforded 12.0 g of a solvent-soluble polymer.

Example 10.

Ball milling was performed in the same way as in Example 1 except that 6.5 ml of isoamyl ether were used instead of ethyl benzoate. The pulverized product was contacted with titanium tetrachloride in the same way as in Example 1 to afford a component (a) which contained 2.1% by weight of tframurr atom and 69% by weight of chlorine atom.

Propylene was polymerized in the same way as in Example 1. There was obtained 325.3 g of polypropylene as a white powder which had a boiling n-heptane extraction residue of 93.3%, an apparent density of 0.35 g/ml, and a melt index of 4.0.

Concentrating the liquid layer afforded 9.9 g of a solvent-soluble polymer.

Example 11.

A reactor equipped with a reflux condenser was charged with 200 ml of Grignard reagent (ethyl ether solution, 2 moles/liter), and 0.4 mole of p-cresol was added dropwise at room temperature. After the reaction, the ethyl ether was removed by distillation. The resulting white powder was suspended in 200 ml of purified kerosene. Ethyl benzoate (0.1 mole) was added to the suspension, and the reaction was performed at 80"C for 2 hours.

After the reaction, the reaction mixture was cooled to room temperature. The resulting solid was colected by filtration, washed with purified hexane, and dried at reduced pressure.

The reaction product was suspended in 300 ml of titanium tetrachloride, and with stirring, reacted at 800C for 2 hours. After the reaction, the product was hot-filtered, and sufficiently washed with purified hexane. Drying under reduced pressure afforded a solid complex titanium component (a) which contained 3.3% by weight of titanium atom, 56% by weight of chlorine atom, 18.7% by weight of magnesium atom, 8.7% by weight of ethyl benzoate, and has a specific surface area of 170 m2/g.

Propylene was polymerized in the same way as in Example 1. There was obtained' 264.2 g of polypropylene as a white powder The polymer had a boiling n-heptane extrac tion residue of 93.7%, an apparent density c 0.32 g/ml, and a melt index of 3.2.

Concentrating the liquid layer afforded 9.7 g of a solvent-soluble polymer.

Example 12.

Anhydrous magnesium chloride (20 g) and 1.2 ml of titanium tetrachloride were placed in a stainless steel (SUS-32) ball mill cylinder having an inner capacity of 800 ml and an inside diameter of 100 mm and having accommodated therein 100 stainless steel (SUS-32) balls having a diameter of 15 mm, and contacted with each other for 30 hours at a speed of 125 rpm. Ten grams of the solid powder obtained was suspended in 100 ml of kerosene and at 60"C, 15 ml of ethyl p-toluate was added dropwise over the course of 30 minutes. The reaction was performed at 700C for 1 hour. The product was collected by filtration, washed with hexane, and dried. Ten grams of the resulting solid product was suspended in 100 ml of titanium tetrachloride, and reacted at 100"C for 2 hours. The product was filtered, sufficiently washed with hexane, and dried. The resulting solid complex titanium component (a) contained 2.0% by weight of titanium atom and 56.0% by weight of chlorine atom.

Propylene was polymerized in the same way as in Example 1. There was obtained 265.4 g of polypropylene as a white powder.

The polymer had a boiling n-heptane extraction residue of 93.7%, an apparent density of 0.32 g/ml and a melt index of 6.2.

Concentrating the liquid layer afforded 10.3 g of a solvent-soluble polymer.

Example 13.

Ten grams of the solid complex titanium compound (a) obtained in the same way as in Example 1 was suspended in 200 ml of purified kerosene, and 6.3 millimoles of titanium tetrachloride was added at room temperature. The reaction was performed for 1 hour. Further, 6.3 millimoles of ethyl benzoate was added, and the reaction was performed for 1 hour. The reaction product was filtered, washed with hexane, and dried to afford a solid complex titanium component (a) which contained 3.5 /5 by weight of titanium atom.

Propylene was polymerized in the same way as in Example 1. There was obtained 276.2 g of polypropylene as a white powder: The polymer had a boiling n-heptane extraction residue of 93.7%, an apparent density of 0.34 g/ml and a melt index of 4.8.

Concentrating the liquid layer afforded 10.2 g of a solvent-soluble polymer.

Examples 14 to 18.

Solid complex titanium components (a) were prepared in the same way as in Example 1 except that ethyl benzoate was changed to electron donors as shown in Table 2, and propylene was polymerized. The results are shown in Table 2.

TABLE 2

Titanium component (a) Results of polymerization Amount Amount of Electron donor supported powdery Amount of Extraction poly- soluble residue of Apparent Amount Ti Cl propylene polymer powder density Melt Example Compound (ml) wt. % wt. % (g) (g) (g) (g/ml) index 14 Methyl benzoate 6.0 2.2 58.7 294.3 9.2 93.7 0.30 5.2 15 Methyl p-toluate 6.0 2.0 60.2 316.5 10.2 93.0 0.29 4.5 16 Isopropyl benzoate 6.0 2.0 59.3 310.1 9.5 92.3 0.30 6.2 17 Anisole 6.5 2.1 61.2 295.7 8.7 90.4 0.31 7.6 18 Dibutyl ether 6.5 2.1 58.3 300.2 13.2 92.1 0.29 5.3 Examples 19 to 23.

Solid titanium complexes were prepared in the same way as in Example 2 except that the alcohol, ester and organoaluminium compound (or tin or silicon compound) were changed as shown in Table 3, and propylene was polymerized in the same way as in Example 1.

The results are shown in Table 3.

TABLE 3

Solid complex titanium component (a) Organoaluminum Amount compound, or Si supported Alcohol Ester or Sn compound Ti Cl Example Name Moles Name Moles Name Moles (wt. %) (wt. %) 19 Butanol 0.4 Ethyl 0.1 Al(Cl2H5)2Cl 0.2 3.8 57.2 benzoate 20 Ethanol 0.4 Ditto 0.1 SiCl4 0.4 3.9 58.7 21 Ethanol 0.4 Ditto 0.1 SnCl4 0.4 4.0 58.0 22 Ethanol 0.4 Methyl 0.1 SnCl4 0.4 3.7 59.3 benzoate 23 Isopropanol 0.6 Ditto 0.1 Al(C2H5)3 0.4 3.2 59.7 TABLE 3 (Continued)

Results of polymerization Powdery Solvent- Extraction poly- soluble residue Apparent propylene polymer of powder density Melt Example (g) (g) (%) (g/ml) index 19 326.3 13.2 94.9 0.30 6.3 20 294.2 15.3 95.1 0.31 4.8 21 311.6 10.0 94.8 0.29 3.7 22 287.7 11.2 95.0 0.32 5.2 23 296.9 9.6 94.3 0.31 4.7

Claims (13)

WHAT WE CLAIM IS:

1. A catalyst composition suitable for use in preparing olefin polymers or copolymers, which comprises: (a) a solid complex titanium component at least containing magnesium, titanium, halogen and an electron donor; (b) an organometallic compound of a metal of Groups I to III of the Periodic Table; and (c) an organic acid anhydride.

2. A catalyst composition according to claim 1, wherein the electron donor is an organic ester or ether.

3. A catalyst composition according to claim 1 or 2, wherein the organometallic compound (b) is an organoaluminium compound.

4. A catalyst composition according to any one of the preceding claims, wherein the acid anhydride (c) is an anhydride of an aliphatic monocarboxylic acid of 2 to 18 carbon atoms, an anhydride of an aliphatic polycarboxylic acid of 4 to 22 carbon atoms, an anhydride of an alicyclic carboxylic acid of 8 to 10 carbon atoms or an anhydride of an aromatic carboxylic acid of 9 to 15 carbon atoms.

5. A catalyst composition according to any one of the preceding claims, wherein the halogen/titanium atomic ratio in the solid complex titanium component (a) exceeds 4:1 and the magnesium/titanium atomic ratio is at least 3:1.

6. A catalyst composition according to claim 1 substantially as described in any one of the Examples.

7. A process for preparing olefin polymers or copolymers, which process comprises polymerising or copolymerising at least one olefin in the presence of a catalyst composition as claimed in any one of the preceding claims.

8. process according to claim 7 wherein the amount of the solid complex titanium component (a) is 0.001 to 5 millimoles as titanium atom per liter of solvent in the case of a liquid-phase reaction in a reaction solvent, and 0.001 to 5 millimoles as titanium atom per liter of polymerisation zone in the case of a vapour-phase reaction.

9. A process according to claim 7 or 8 wherein the amount of the organometallic compound (b) is 0.1 to 50 millimoles as the metal atom per liter of solvent in the case of a liquid phase reaction in a reaction solvent, and is 0.1 to 50 millimoles as the metal atom per liter of polymerisation zone in the case of a vapour phase reaction.

10. A process according to claim 7, 8 or 9 wherein the amount of the acid anhydride (c) is 0.001 to 1 mole per metal atom of the organometallic compound (b).

11. A process according to any one of claims 7 to 10 wherein the olefin is an a-olefin containing at least 3 carbon atoms.

12. A process according to claim 7 substantially as described in any one of the Examples.

13. Olefin polymers or copolymers when prepared by a process as claimed in any one of claims 7 to 12.