WO1994016816A1

WO1994016816A1 - Four component polymerization catalyst

Info

Publication number: WO1994016816A1
Application number: PCT/US1994/000667
Authority: WO
Inventors: Raghu Menon; Albert P. Masino; Mark K. Reinking
Original assignee: Quantum Chemical Corporation
Priority date: 1993-01-29
Filing date: 1994-01-26
Publication date: 1994-08-04
Also published as: ZA94611B; AU6031294A

Abstract

A catalyst which comprises (a) a solid catalyst component which includes a magnesium-containing agent and at least one transition metal-containing agent; (b) an organometallic compound where the metal is a metal of Group II or Group III of the Periodic Table of the Elements; (c) a hydrocarbylhydrocarbyloxysilane compound; and (d) a halosilane compound is disclosed. This catalyst is useful in the polymerization of olefins.

Description

FOUR COMPONENT POLYMERIZATION CATALYST

The polymerization of olefins using Ziegler-Nattatype catalyst systems is very widely utilized. These catalyst systems provide polyolefins possessing desired characteristics in high yield. However, all such catalysts have failings, the improvement of which is the subject of continual research and development.

Among these failings, catalysts used in the

polymerization of alpha-olefins usually include a solid catalyst component which oftentimes include a magnesium halide support. Unfortunately, when polyolefins which are catalytically polymerized employing such a magnesium halide supported catalyst component are processed into molded articles the molding apparatus is subject to corrosion. This corrosion is caused by the residual presence of magnesium halide in the polymeric product. Significantly, the adverse effects of employing a magnesium halide support are not limited to corrosion damage of expensive molding machinery. More

importantly, the polymeric molded article processed in such corrosion damaged eguipment is often characterized by aesthetic flaws.

Of course, of all the properties associated with a catalyst, probably the most significant one is its activity. That is, the effectiveness of a

polymerization catalyst is measured by the amount of polymeric product produced per unit amount of catalyst.

Obviously, this property must be considered along with the effect of the catalyst on the properties of the polymer. For example, in the polymerization of

propylene polymers it is often essential that the degree of crystallinity be sufficiently high to be useful in important applications. Oftentimes, such a

characteristic can only be obtained by sacrificing catalytic activity, i.e., weight of propylene polymer per unit weight of catalyst. Those skilled in the polymeric arts are aware, however, that high catalyst activity not only increases the efficiency of the polymerization process but also has a significant positive effect on the purity of the polymer product. This is so because the higher the catalytic activity the lower the catalyst impurity concentration in the final polymeric product.

The above remarks make clear the continuing need in the art for a new olefin polymerization catalyst having the desired properties considered above.

U.S. Patent 4,950,631 describes a catalyst system which incorporates a silica-supported magnesium- and titanium-containing catalyst component which is employed with an aluminum-containing compound and a non-halogen- containing silane compound to produce olefin polymers, especially propylene polymers, having excellent

catalytic activity as well as superior polymer

properties.

A similar catalyst system is described in U.S.

Patent 5,034,365. This catalyst is distinguished from the aforementioned catalyst of the '631 patent by an additional treatment step in the formation of the silica-supported magnesium- and titanium-containing catalyst component. This additional step is the treatment of the catalyst component with a halosilane. Otherwise, the catalyst system of the '365 patent is substantially identical with the catalyst system of the '631 patent.

U.S. Patent 5,037,789 is very similar to the '631 patent discussed above. The only distinction between the catalyst system of the '789 patent and the catalyst system of the '631 patent is the unsupported nature of the solid catalyst component of the '789 patent. That is, the catalyst system of the '789 patent is identical with that of the '631 patent but for the absence in the solid catalyst component of a support.

A catalyst system which is also very similar to the catalyst system of the '631 patent is disclosed in U.S. Patent 5,051,388. The '388 patent describes a catalyst system which differs from the catalyst system of the '631 patent by the inclusion of vanadium, as well as titanium, in the solid catalyst component of that system.

U.S. Patent 4,451,688 discloses a process for preparing a polyolefin wherein an olefin is polymerized in the presence of a catalyst system which comprises a solid component which is the reaction product of a magnesium-containing compound and a titanium and/or vanadium-containing compound. A second catalyst

component is a silicon-containing compound having the structural formula R'_mSi(OR'')_nX_4-m-n, where R' and R'' are each hydrocarbon radicals having 1 to 24 carbon atoms; X is a halogen atom; m is 0 or an integer of 1 to 3; and n is an integer of 1 to 4. The catalyst system also includes a third catalyst component, an

organometallic compound in which the metal of the organometallic compound is preferably aluminum or zinc. U.S. Patent 4,857,613 describes a catalyst system that includes a titanium component based on finely divided silica gel which contains titanium, magnesium, chlorine and a benzenecarboxylic acid derivative. The catalyst system also includes an aluminum component and a silane component.

U.S. Patent 4,374,753 is directed to a solid catalyst component in which any one of a broad range of organic silicon compounds is disposed on a silica or alumina support having surface hydroxyl groups. To this product is added an organomagnesium compound and an alcohol. The seguence of contact with the organo- magnesium compound and the alcohol is random. The product of contact of these two components, independentθf the sequence of their contact with the support, is reacted with a halide or alkoxide of titanium, vanadium, zirconium or mixtures thereof. The resultant solid catalyst component is employed with an alkyl or aryl aluminum co-catalyst to provide an olefin polymerization catalyst system.

Although the above-discussed references are

relevant to the catalyst system of the present

invention, none of them disclose a catalyst system having the advantages discussed hereinafter.

A new catalyst has now been developed which

catalyzes the polymerization of olefins resulting in the formation of polymers having desirable physical

properties which desirable polymers are further produced in a yield heretofore unobtainable. Thus, the catalyst of the present invention represents an advance in the catalysis art in view of the combination of yield and physical properties of the polyolefin product. In accordance with the present invention a catalyst is provided which comprises a solid catalyst component which includes the product of a magnesium-containing agent and at least one transition metal-containing agent. The catalyst also includes, as a second

component, an organometallic compound wherein the metal of that compound is a metal of Group II or III of the Periodic Table of the Elements. A third component of the catalyst is a hydrocarbyl-hydrocarbyloxysilane compound. Finally, the catalyst includes, as a fourth component, a halosilane compound.

A catalyst is provided which includes, as a first component, a solid catalyst component which comprises the product of a magnesium-containing agent and at least one transition metal-containing agent. The class of solid catalyst components within the contemplation of the solid catalyst component of the catalyst of this invention is substantially unlimited. That is, the requirement imposed on this first component is limited only by the necessity that there be contact between a magnesium-containing agent and at least one transition metal-containing agent.

The scope of magnesium-containing agents within the contemplation of the solid component includes elemental magnesium metal and magnesium-containing compounds.

Preferably, the magnesium-containing agent is a

magnesium-containing compound. Such magnesium- containing compounds as a magnesium halide, a

hydrocarbylmagnesiumtrihydrocarbylsilyl amide, a

dihydrocarbylmagnesium compound, a dihydrocarbyloxymagnesium compound, a hydrocarbylmagnesium halide, a hydrocarbyloxymagnesium halide and the like are preferred. Of these, those magnesium-containing

compounds which are hydrocarbon soluble are preferred. Thus, in a preferred embodiment, the magnesium- containing compound of the solid catalyst component is selected from the group consisting of dihydrocarbylmagnesium compounds, dihydrocarbyloxymagnesium

compounds, hydrocarbylmagnesium-trihydrocarbylsilyl amides, hydrocarbylmagnesium halides and hydrocarbyloxymagnesium halides.

The hydrocarbyl component of the hydrocarbyl- containing magnesium compounds can be alkyl, aryl, alkaryl, aralkyl, alkenyl, alkynyl, alkenylaryl,

arylalkenyl and the like. Of these, alkyl is preferred. Similarly, the hydrocarbyloxy component of the

hydrocarbyloxy-containing magnesium compounds can be alkyloxy, aryloxy, alkaryloxy, aralkyloxy, alkenyloxy, alkynyloxy, alkenylaryloxy, arylalkenyloxy and the like. Of these, alkyloxy is preferred.

The transition metal-containing agent utilized in the first solid catalyst component may be an elemental transition metal but is preferably a transition metal- containing compound. Of the transition metals that may be included in the transition metal-containing compound, the transition metals titanium, vanadium and zirconium are preferred. Of these, organometallic compounds wherein the metals of which are titanium and vanadium are particularly preferred. Titanium is the most preferred transition metal employed in transition metal- containing compounds within the contemplation of this invention.

In another preferred embodiment, two transition metal compounds are employed. In this preferred embodiment, it is oftentimes desirable to use titanium and vanadium, provided by titanium- and vanadium- containing compounds.

The solid catalyst component may or may not include an inorganic oxide support. The inorganic oxide

support, if employed, may be any inorganic oxide such as silica, alumina, titania, zirconia, magnesia, mixtures thereof and the like. Of these supports, the most preferred inorganic oxide support is silica.

Independent of the identity of the inorganic oxide support, that support may or may not be surface treated to remove surface hydroxyl groups. That is, the

support, if employed, may or may not be surface treated. Furthermore, again independent of the identity of the support, it is also preferable to employ a finely divided inorganic oxide as the support. For example, in the preferred embodiment wherein silica is utilized as the support, it is preferred that the support be finely divided silica gel.

A second catalyst component of the catalyst of this invention is an organometallic compound wherein the metal of that compound is a metal of Group II or Group III of the Periodic Table of the Elements. Of the Group II and Group III metals, aluminum and zinc are

preferred, with aluminum being particularly preferred.

The organometallic compound, in which these Group II and Group III metals are provided, is preferably a hydrocarbylmetal compound, a hydrocarbyloxymetal

compound, a hydrocarbylhydrocarbyloxymetal compound, a hydrocarbyl-metal halide, a hydrocarbyloxymetal halide, a hydrocarbyl-hydrocarbyloxymetal halide and the like. Of these classes of organometallic compounds, a hydrocarbylmetal compound and a hydrocarbylmetal halide compound are particularly preferred. For example, in the preferred embodiment wherein the Group II or Group III metal is aluminum, alkylaluminum compounds and alkylaluminum halides are particularly desirable. Most preferably, the second catalyst component of the

catalyst of this invention is an alkylaluminum compound having the structural formula

AIR, (I) where R is C₁ to C₁₂ alkyl, more preferably, C₂ to C₄ alkyl.

The third catalyst component of the catalyst of this invention is a hydrocarbylhydrocarbyloxysilane compound. Hydrocarbylhydrocarbyloxysilane compounds within the contemplation of the present invention are preferably characterized by the structural formula

H_4-a-b-c-dR¹ _aR² _b(OR³)_c (OR⁴)_dSi (II) where R¹, R², R³ and R⁴ are the same or different and are C₁-C₁₂ alkyl, C₆-C₁₀ aryl, C₇-C₁₄ aralkyl or C₇-C₁₄ alkaryl; a is an integer of 1 to 3; b is 0 or an integer of 1 or 2; c is an integer of 1 to 3; and d is 0 or an integer of 1 or 2. Preferably, the

hydrocarbylhydrocarbyloxy-silane compound having the structural formula II is characterized by R¹, R², R³ and R⁴ being the same or different and being C₁-C₆ alkyl.

The fourth and last component of the catalyst of the present invention is a halosilane compound. The halosilane compound of the catalyst is preferably a compound having the structural formula

H_mY_nSiX_4-m-n (III) where Y is alkyl, alkoxy, aryl, aryloxy, aralkyl, aralkyloxy, alkaryl or alkaryloxy; X is halogen; and m and n are the same and different and are 0 or an integer of 1 to 3 with the provisos that m and n cannot both be 0 and that the sum of m and n cannot exceed 3.

More preferably, the halosilane compound having the structural formula III is defined by Y being alkyl; and X being chlorine.

Still more preferably, in those embodiments where the solid catalyst component contains titanium but does not contain vanadium, the halosilane compound having the structural formula III is dichlorosilane or trichloro- silane. In those preferred embodiments where the solid catalyst component contains both titanium and vanadium, trimethylchlorosilane is particularly preferred.

The four catalyst components which comprise the catalyst of this invention are preferably present in concentrations such that the molar ratio of the second catalyst component, the organometallic compound where the metal thereof is a metal of Group II or III of the Periodic Table, to the third catalyst component, the hydrocarbyl-hydrocarbyloxysilane compound, is in the range of between about 1:1 and about 10:1. It is similarly preferred that the molar ratio of the third catalyst component to the fourth catalyst component, the halosilane compound, be in the range of between about 1:0.1 and about 1:10. More preferably, this molar ratio of third to fourth catalyst components is in the range of between about 1:0.25 and about 1:3. Finally, it is preferred that the molar ratio of titanium in the first catalyst component, the solid catalyst component, bePresent such that the molar ratio of titanium to second catalyst component is in the range of between about 1:0.001 and about 1:1. More preferably, the molar ratio of titanium to second catalyst component is in the range of between about 1:0.005 and about 1:0.25.

As suggested above, the class of solid catalyst components within the contemplation of the catalyst of this invention is quite extensive. Indeed, there are a multiplicity of preferred embodiments of the first solid catalyst component, ϊn one such preferred embodiment, a first modifying compound, selected from the group consisting of silicon halides, boron halides, aluminum halides, alkyl silicon halides and mixtures thereof, is contacted with at least one hydrocarbon soluble

magnesium compound. The hydrocarbon soluble magnesium compound of this embodiment is preferably selected from the group consisting of dihydro-carbyloxymagnesium compounds, hydrocarbyloxymagnesium halides and mixtures thereof.

In this preferred embodiment the first modifying compound is preferably selected from the group

consisting of silicon tetrachloride, boron trichloride and aluminum trichloride. The hydrocarbon soluble magnesium compound, which is contacted with the first modifying compound, in this preferred embodiment, is preferably a dialkoxy-magnesium compound or an

alkoxymagnesium chloride. Of these, alkoxymagnesium chlorides are preferred. More preferably, the alkoxy component of the hydrocarbon soluble magnesium compound includes between about 4 and about 12 carbon atoms.

Still more preferably, the alkoxy of the alkoxymagnesium chloride is one which includes about 8 to about 12 carbon atoms .

The product of contact between the solid catalyst component and the first modifying compound is, in turn, contacted with a titanium-containing compound. This titanium-containing compound has the structural formula

TiX² _q(OR⁶)_4-q (IV) where X² is halogen; R⁶ is hydrocarbyl; and q is an integer of 1 to 4. Preferably, X² is chlorine or bromine; R⁶ is alkyl, aryl or alkaryl; and q is an integer of 2 to 4. More preferably, X² is chlorine; and q is 4.

In another preferred embodiment of the catalyst of this invention the solid catalyst component is

supported. That is, the solid catalyst component is prepared in accordance with the preferred embodiment discussed above except that the first modifying compound and the hydrocarbon soluble magnesium compound contact each other on an inorganic oxide support. It is noted that the order of contact of the first modifying

compound and the hydrocarbon soluble magnesium compound with the support is random.

Of the inorganic oxide supports discussed earlier, silica is particularly preferred for use in this

embodiment. In a further preferred embodiment wherein silica is utilized as the support, the silica support is pretreated to replace surface hydroxyl groups with groups having the structural formula )

This surface treatment, in one preferred

embodiment, is effected by calcining the silica support in an inert atmosphere, preferably at a temperature of at least about 200°C. More preferably, the calcining treatment involves calcining the silica at a temperature in the range of between about 550°C and about 650°C in an inert atmosphere, preferably, a nitrogen atmosphere.

In a second preferred embodiment of the surface treatment of the silica support, the removal of surface hydroxyl groups is accomplished by treating the silica with a hexaalkyl disilazane. Of the hexaalkyl

disilazanes useful in this application, hexamethyl disilazane is preferred.

A third preferred embodiment of silica support treatment involves a combination of the first two preferred treatment embodiments. In this third

preferred embodiment the silica employed as the support is calcined in accordance with the first preferred embodiment and thereafter treated with a hexaalkyl disilazane in accordance with the second preferred embodiment.

The silica, whether modified or not, preferably has a surface area in the range of between about 80 and about 300 square meters per gram, a median particle size of between about 20 to about 200 microns and a pore volume of between about 0.6 and about 3.0 cc/gram. Two additional preferred embodiments of the silica of this invention involves one variation of the two above- discussed solid catalyst components. This modification comprises an additional contacting step between the step of contact between the product of the first modifying compound and at least one hydrocarbon soluble magnesium compound and the step of contacting that product with a titanium-containing compound having the structural formula IV. In this additional step a second modifying compound selected from the group consisting of a compound having the structural formula

SiH_rX³ _4-r (VI) where X³ is halogen; and r is an integer of 1 to 3, and a compound having the structural formula

HX³ (VII) where X³ has the meaning given above.

In this embodiment it is preferred that X³ be chlorine and r be an integer of 1 or 2. In a

particularly preferred embodiment, the second modifying compound is selected from the group consisting of dichlorosilane and trichlorosilane.

In the preferred embodiment where the solid

catalyst component is supported, the random order of contact with the inorganic oxide support of the first modifying compound and the hydrocarbon soluble magnesium compound is unchanged. However, this preferred

embodiment is limited by the requirement that the second modifying compound contact the product of said first modifying compound and said hydrocarbon soluble

magnesium compound. In yet four further preferred embodiments of the catalyst of this invention the first catalyst component is any of the four above-mentioned embodiments, the embodiments where the solid catalyst component is unsupported or supported on an inorganic oxide, with or without a second modifying compound treatment step, wherein the further step of contacting the product of contact with the first or the second modifying compound, as the case may be, with a transition metal-containing compound is included. This contact occurs prior to contact with the titanium-containing compound having the structural formula IV.

In these preferred embodiments, independent of whether or not the component is supported and

independent of whether or not there is contact with a second modifying compound, it is preferred that the transition metal of the transition metal-containing compound be titanium, vanadium or zirconium.

More preferably, the transition metal-containing compound is selected from the group consisting of a titanium-containing compound having the structural formula Ti(OR⁵)_pX¹ _4-p (VIII) where R⁵ is hydrocarbyl; X¹ is halogen; and p is an integer of 1 to 4, and a vanadium-containing compound having the structural formula

V ( OR ⁷ ) _e ( O ) _fX_g (IX) where R⁷ is hydrocarbyl; X⁴ is halogen; e is 0 or an integer of 1 to 3; f is 0 or 1; and g is 0 or an integer of 1 to 4, with the proviso that the sum of e, f and g is an integer of 2 to 4.

More preferably, the vanadium-containing compound has the structural formula (IX) is characterized by e is 0; f is 0 or 1; and g is an integer of 2 to 4, with the proviso that the sum of f and g is 2 to 4.

Still more preferably, the titanium-containing compound has the structural formula VIII, where R⁵ is alkyl or alkaryl; X¹ is chlorine or bromine; and p is an integer of 2 to 4. Similarly, the vanadium-containing compound having the structural formula IX is more preferably defined by X⁴ being chlorine or bromine; and e being 0.

Even still more preferably, the titanium-containing compound has the structural formula VIII, where R⁵ is alkaryl; and p is 4. The vanadium-containing compound, in this even still more preferred embodiment, has the structural formula IX, where X⁴ being chlorine.

Even more preferably, the transition metal- containing compound is titanium tetracresylate, vanadium oxychloride or vanadium tetrachloride.

In yet four additional embodiments of the catalyst of the present invention, the solid catalyst component is prepared in accordance with one of the four

embodiments of the solid catalyst component discussed immediately above wherein a titanium, vanadium or zirconium compound is employed to contact the product of contact with the first or second modifying compounds. In these four embodiments the solid catalyst component is prepared in accordance with the embodiments which include the step of incorporating a transition metal- containing compound. However, that transition metal compound is restricted by the requirement that it be the titanium-containing compound having the structural formula VIII.

In these four embodiments an additional step is added. This additional step involves contact of the product obtained by treatment with the compound having the structural formula VIII with a vanadium-containing compound. That vanadium-containing compound contacting step occurs prior to contact with the titanium- containing compound having the structural formula IV.

The vanadium-containing compound used in the formation of the solid catalyst component of this preferred embodiment of the catalyst is a compound having the structural formula IX. Preferred and more preferred embodiments of the compound having the structural formula IX, as defined in the discussion of the four previous embodiments, are preferred and more preferred embodiments of the vanadium-containing compound.

in another preferred embodiment of the catalyst of this invention the solid catalyst component is prepared by disposing a hydrocarbon soluble organomagnesium compound upon an inorganic oxide support. Preferably, the organomagnesium compound has the structural formula

MgR⁸R⁹ (X) where R⁸ and R⁹ are the same or different and are hydrocarbyl and the inorganic oxide support is silica.

More preferably, the organomagnesium compound has the structural formula X, where R⁸ and R⁹ are the same or different and are C₂ to C₁₀ alkyl, and the silica support has the size and physical properties discussed earlier. It is particularly preferred that the silica have a surface area of between about 200 m²/g and about 500 m²/g, a particle size of between about 10 microns and about 200 microns and a pore volume of about 1 cc/g to about 3 cc/g. It is even more preferred that the silica have the structural formula

SiO₂.xAl₂O₃ (XI) where x is 0 to 2, preferably 0 to about 0.5.

In this preferred embodiment the next step involves adding a gaseous halogenating agent to the

organomagnesium compound disposed on the inorganic oxide support. The gaseous halogenating agent is a compound having the structural formula

ZX⁵ (XII) where Z is hydrogen, chlorine or bromine; and X⁵ is chlorine or bromine, with the proviso that if Z is chlorine or bromine X⁵ must be the same.

Preferably, the gaseous halogenating compound has the structural formula XII where Z is hydrogen or chlorine; and X⁵ is chlorine. More preferably, Z is hydrogen, that is, the halogenating agent is hydrogen chloride.

To this product is added a C₁ to C₆ alkanol, preferably ethanol, and a titanium-containing compound having the structural formula IV, which can be any of the preferred and more preferred embodiments of said structural formula IV discussed earlier. As in the earlier embodiments, the titanium-containing compound having the structural formula IV is most preferably titanium tetrachloride. Finally, a compound having the structural formula

where Y¹ and Y² are the same or different and are chlorine, bromine, C₁ to C₁₀ alkoxy or Y¹ and Y² taken together are oxygen may be included in the formation of the solid product. More preferably, Y¹ and Y² are the same and are C₁ to C₈ alkoxy. Most preferably, Y¹ and Y² are both n-butoxy.

In yet another embodiment of the solid catalyst component an inorganic oxide support of the type discussed above is contacted with an organic silicon compound. The inorganic oxide support, which is preferably silica or alumina, is contacted with one of two organosilicon compounds. The organosilicon

compounds have the structural formulae

(R¹⁰ ₃Si)₂NH (XIV) and

R_g ¹⁰SiX⁶ _4-g (XV) where R¹⁰ is hydrocarbyl; X⁶ is a group reactive with the hydroxyl groups on the surface of the inorganic oxide support; and g is an integer of 1 to 3.

More preferably, the organosilicon compounds have the structural formulae XIV and XV, where R¹⁰ is alkyl. phenyl or alkenyl; and X⁶ is halogen, alkoxy, amido or phenoxy.

It is emphasized that, as in the case of the inorganic oxide supports discussed earlier, the support may be treated to remove surface hydroxyl groups in accordance with one of the recited procedures.

To this product is added an organomagnesium

compound and an alcohol. It is important to appreciate that the sequence of addition of the organomagnesium compound and the alcohol is random. That is, the order of contact of the organomagnesium compound and the alcohol on the inorganic oxide support is not critical.

The organomagnesium compound employed in the formation of the solid catalyst component preferably has one of the following structural formulae:

R¹¹MgX⁷ (XVI) R¹¹R¹²Mg (XVII)

(R¹¹ ₂Mg)_h.AlR¹¹ ₃ (XVIII) where R¹¹ is alkyl, aryl, alkaryl, aralkyl or alkenyl; R¹² is alkyl; X⁷ is halogen; and h is 0.5 to 10. More preferably, the organomagnesium compound has one of the structural formulae XVI, XVII or XVIII where R¹¹ is C₁-

C₁₀ alkyl, phenyl, naphthyl or cyclopentadienyl; and X⁷ is chlorine or bromine.

The alcohol employed in this embodiment of the solid catalyst component preferably has the structural formula R^{1 3}OH ( XIX ) where R¹³ is C₁-C₆ alkyl, phenyl or benzyl. More preferably, the alcohol has the structural formula XIX where R¹³ is C₁-C₄ alkyl or benzyl. Of the alcohols within the contemplation of the solid catalyst component of this embodiment, n-butyl alcohol and benzyl alcohol are particularly preferred.

To the product of the organic silicon compound, the organomagnesium compound and the alcohol disposed upon the inorganic oxide support is added a compound which includes titanium, vanadium, zirconium or mixtures thereof. Of these, a titanium-containing compound is preferred. A particularly preferred class of titanium- containing compounds are those having the structural formula IV. Even more preferred embodiments of the titanium compound of this embodiment are those preferred titanium compounds provided in the discussion of

preferred embodiments of the compounds having the structural formula IV. Thus, in accordance with that discussion, the most preferred titanium-containing compound for use in the formation of this preferred embodiment of the solid catalyst component is titanium tetrachloride.

The catalyst of the present invention, the catalyst system which includes one of the solid catalyst

components discussed above; the organometallic compound, where the metal is one of Group II or III of the

Periodic Table; the hydrocarbylhydrocarbyloxysilane compound; and the halosilane compound, is employed as a polymerization catalyst. Preferably, the polymerization which is aided by the catalyst of this invention is the polymerization of one or more olefins. More preferably, this catalyst is employed in the polymerization of at least one alpha-olefin. Still more preferably, the catalyst within the contemplation of this invention isused to polymerize alpha-olefins containing 2 to 12 carbon atoms. Even still more preferably, the catalyst of the present invention is employed in the

polymerization of alpha-olefins which contain 2 to 6 carbon atoms. Most preferably, this catalyst is used in the polymerization of the alpha-olefins, ethylene and propylene.

These catalysts may be employed in solution, suspension or gas phase polymerization processes under usual thermodynamic conditions associated with such polymerization processes. Such conditions, under which continuous or batch polymerization occurs, include temperatures from ambient to about 300°C and pressures ranging from ambient to about 10,000 psig.

The following examples are provided to illustrate the scope of the present invention because these

examples are given for illustrative purposes only, the present invention should not be limited thereto.

EXAMPLE 1

Preparation of a Solid Catalyst Component

Silicon tetrachloride (12.5 mmol.) and silica

(5.0 g.) previously calcined in nitrogen at 600°C and characterized by a specific surface area of 300 m²/g., a median particle size of 80 to 90 microns and a pore volume of 1.3 cc/g. were introduced into a 250 ml. round bottom flask, equipped with a nitrogen purge, a paddle stirrer, a stirring gland, a condenser and a bubbler partially filled with heptane (20 ml.) The flask, prior to the introduction of heptane, had been purged with nitrogen. The resultant slurry was heated at 60°C for 1 hour with stirring. Thereupon 2-methyl-1- pentyloxymagnesium chloride (12.5 mmol.) was added to the slurry. This product was heated at 70°C for 1 hour with stirring. Titanium tetracresylate (3.175 mmol.) was added to the resultant product and this product was also heated with stirring at 70°C for 1 hour.

The solid product of these contacting steps was allowed to settle and the supernatant liquid siphoned off. Additional heptane (50 ml.) was added to the solid and stirring was instituted without any heating. The solid was again allowed to settle and the supernatant liquid was siphoned off. This washing step was repeated three additional times so that a total of 200 ml. of supernatant liquid was removed by siphoning. Liquid titanium tetrachloride (90 mmol.) was added to the washed solid and remained in contact with the solid for 2 hours at a temperature which ranged from 80°C to 100°C during which time the contacting species were subjected to stirring. The solid product of this contact was washed three additional times with heptane (50 ml. wash) in accordance with the procedure provided hereinbefore.

The solid product resulting from these washings wasa salmon-colored, free flowing spherically-shaped solid catalyst component. Upon analysis it was found that this solid comprised 2.37 % Ti and 4.2 % Mg, said percentages being by weight, based on the total weight of the solid catalyst component.

EXAMPLE 2

Preparation of a Solid Catalyst Component

A master batch was prepared by charging silica (6 lb.) into a ribbon blender. The silica was Davison [trademark] 948, a silica pretreated with hexamethyl disilazane having similar physical properties to the silica used in Example 1. The silica in the blender was heated for 1 hour under a nitrogen purge at a

temperature in the range of 90°C to 100°C. The silica in the blender was then cooled to ambient temperature. A solution (16.8 lb.) of 2-methyl-1-pentyloxymagnesium chloride in heptane (17.2 wt %) was thereupon introduced into the blender. The contents of the blender were heated with stirring under a nitrogen atmosphere for 2 to 3 hours at a temperature of 100°C. At the conclusion of this heating step, the solvent was partially removed(67%) by evaporation leaving a dry, free flowing

product. The product was analyzed and found to possess the following constituency: SiO₂, 47.9%; Mg, 4.67%; Cl, 15.8; and heptane, 31.63%, all said percentages being by weight, based on the total weight of the product.

Master batch (8 g. ) was introduced into a 250 ml. flask, identical to and identically equipped to the flask employed in Example 1. Heptane (10 ml.) was added and stirring was commenced. To this suspension was added silicon tetrachloride (2.55 ml., 20 mmol.)followed immediately by the addition of trichlorosilane (0.45 ml., 4 mmol.). The thus included contents were heated at 40°C with stirring for 40 minutes. The flask and its contents were cooled to ambient temperature. The solid product was separated from the supernatant liquid and contacted with heptane (70 ml.). The

resultant slurry was stirred for 5 minutes. Stirring was then stopped and the solids were allowed to settle. The supernatant liquid was siphoned off. This washing procedure was repeated two more times for a total of three washings.

The washed product was contacted with titanium tetrachloride (10 ml., 90 mmol.) followed by heating for 1 hour at 90°C. The solid product of this contact was washed six times with heptane (in each case 80 ml.). The thus washed solid catalyst component product was dried with nitrogen gas and analyzed by X-ray

fluorescence. The analysis indicated the followingconstituency: Ti, 5.3%; Mg, 3.9%; SiO₂, 47.3%; and Cl, 13.1%, all said percentages being by weight, based on the total weight of the solid catalyst component.

EXAMPLE 3

Preparation of a Solid Catalyst Component

A solid catalyst component was formed in accordance with the disclosure in U.S. Patent 4,857,613, which patent is incorporated herein by reference.

Specifically, the solid catalyst component of this example was prepared in accordance with the disclosure of Example 1 thereof, the example wherein a titanium- containing catalyst component is prepared.

The solid catalyst component of this example was characterized by a titanium content of 3.3 weight percent and a magnesium content of 6.25 weight percent, based on the total weight of the catalyst component.

EXAMPLE 4

Polymerization of Propylene

A catalyst system comprising triethylaluminum

(TEAL), isobutylisopropyldimethoxysilane (IBIP),

trichloro-silane (HSiCl₃) and the solid catalyst

component of Example 1 provided in a molar ratio of 137:13.7:12.8:1 were introduced into a 2-liter Autoclave Engineers [trademark] reactor. The solid catalyst component of Example 1 and the TEAL were separately introduced. However, the two liquid silane components, IBIP and HSiCl₃, were premixed prior to introduction into the reactor. To the catalyst components were added liquid propylene (1000 ml.) and the reactor was

thereupon heated to 77°C and pressurized to 500 psig where-upon a polymerization reaction of 1 hour duration was initiated. After 1 hour the reactor was cooled and depressurized to ambient temperature and pressure and the polypropylene product removed.

The polypropylene (PP) product was weighed and its activity, in terms of grams of PP per gram of solid catalyst component, was determined.

The melt flow rate of this PP product was analyzed, in accordance with ASTM Test Procedure D-1238. The % heptane insolubility, a measurement of the isotacticity of the PP product, was determined by a procedure

involving the preparation of finely ground sample (20 mesh) of the PP which was disposed in a tare container (a thimble) and heated for 30 minutes at 100°C in a vacuum oven. The PP, still disposed in its container, was thereupon weighed. The PP-filled container was placed in an extraction flask filled with n-heptane (150 ml). The n-heptane was heated to boiling and refluxed for 90 minutes. After 90 minutes refluxing ceased and the container filled with the ground PP sample removed. The PP-filled container was rinsed in acetone and again heated for 30 minutes at 100°C in the vacuum oven. The PP-filled container was cooled and again weighed.

Percent heptane insolubility was determined as the ratio of the difference in net weight of the PP before and after contact with boiling n-heptane divided by the weight of PP prior to such contact.

The bulk density of the polypropylene product was determined. This property, measured in grams per cubic centimeter, was determined by filling a container of known volume which had previously been weighed with PP generated during the run and weighing the filled

container. The difference in filled and unfilled weight divided by the known volume represented the bulk

density.

Finally, the PP produced in this example was analyzed to determine the residue of catalyst retained in the polymer product. To this end, the product was analyzed to determine its titanium, chlorine and silicon concentration on a weight basis, measured in parts per million, by X-ray fluorescence technique.

The results of these tests are provided in the Table following the last example.

COMPARATIVE EXAMPLE 1

Polymerization of Propylene

Example 4 was identically reproduced but for the omission of the HSiCl₃ component from the catalyst components charged into the 2-liter Autoclave Engineers [ trademark] reactor.

The results of this example are included in the Table.

EXAMPLE 5

Polymerization of Propylene

Example 4 was identically reproduced but for the substitution of the hydrocarbylhydrocarbyloxysilane component of the catalyst system of that example, IBIP, with diisopropyldimethoxysilane (DIPS).

The polypropylene product of this polymerization reaction was analyzed in accordance with the analytical tests discussed in Example 4 with the exception that the melt flow rate test was conducted in accordance with the high load melt flow test set forth in ASTM Test

Procedure D-1238, i.e., under a load of 21.6 kg. at a temperature of 230°F.

The results of this example are included in the Table.

COMPARATIVE EXAMPLE 2

Polymerization of Propylene

Example 5 was reproduced except that the halosilane component of the catalyst system of that example,

HSiCl₃, was omitted.

The results of this example are included in the Table.

EXAMPLE 6

Polymerization of Propylene

Example 4 was reproduced except for the

substitution of the solid catalyst component of Example 2 instead of the solid catalyst component of Example 1.

The results of this example are included in the Table.

COMPARATIVE EXAMPLE 3

Polymerization of Propylene

Example 6 was reproduced except for the omission of the halosilane component of the catalyst system, HSiCl₃. The results of this example are provided in the Table.

EXAMPLE 7

Polymerization of Propylene

A catalyst system comprising TEAL, IBIP, HSiCl₃ and the solid catalyst component of Example 3 was charged into the 2-liter Autoclave Engineers [trademark] reactor in a molar ratio of 312:30:30:1, respectively, where thesolid catalyst component is measured in terms of its titanium concentration. As in Example 4, the solid catalyst component of Example 3 and the TEAL were separately introduced. However, the two liquid silane components, IBIP and HSiCl₃, were premixed prior tointroduction into the reactor. The catalyst components were added to liquid propylene (1000 ml.) and the reactor was thereupon maintained at a temperature of 70°C and a pressure of 450 psig for 1 hour. After 1 hour, the reactor was cooled and depressurized toambient temperature and pressure and the propylene product removed.

The propylene (PP) product was weighed and its activity, in terms of grams of PP per gram of solid catalyst component, was determined.

In a separate test, conducted in accordance with ASTM test procedure D-1238, the melt flow rate of the PP product was determined.

The measurement of isotacticity was obtained by determining the percent heptane insolubility of the PPproduct. This test was conducted in accordance with the procedure set forth in Example 4.

Bulk density of the PP product was calculated in accordance with the procedure mentioned in Example 4. Finally, the catalyst residue present in the PP product was determined by X-ray fluorescence. This analysis was limited to the determination of thetitanium and the chlorine residues in the PP product.

The results of this example are summarized in the Table.

EXAMPLE 8

Polymerization of Propylene

Example 7 was identically reproduced but for the ratio of the catalyst component of the catalyst system. In Example 8 the molar ratio of TEAL to IBIP to HSiCl₃ to titanium in the solid catalyst component was

188:18:18:1.

All the tests defining catalyst activity and the product polypropylene physical properties conducted in Example 7 were repeated in Example 8. These results are summarized in the Table.

COMPARATIVE EXAMPLE 4 Polymerization of Propylene

Example 7 was identically reproduced but for the omission of the halosilane HSiCl₃ component. Thus, the catalyst system constituted TEAL, IBIP and the solid catalyst component. The molar ratio of these components was 170:16:1, respectively, wherein the molar

constituent of the solid catalyst component was again measured in terms of its titanium concentration.

The results of this example are included in the Table.

The above embodiments and examples are given to illustrate the scope and spirit of the present

invention. These embodiments and examples will makeapparent, to those skilled in the art, other embodiments and examples. These other embodiment and examples are within the scope of the present invention. Therefore, the present invention should be limited only by the appended claims.

Claims

WHAT IS CLAIMED IS:

1. A catalyst comprising:

(a) a solid catalyst component which includesa magnesium-containing agent and at least one transition metal-containing agent;

(b) an organometallic compound, where the metal of that compound is a metal of Group II or III of the Periodic Table of the Elements;

(c) a hydrocarbylhydrocarbyloxysilane compound; and

(d) a halosilane compound.

2. A catalyst in accordance with Claim 1 whereinsaid catalyst component (b) is an organoaluminum

compound

3. A catalyst in accordance with Claims 1 or 2 wherein said organoaluminum compound has the structuralformula A1R₃, where R is C₁ to C₁₂ alkyl.

4. A catalyst in accordance with any of Claims 1-3 wherein said catalyst component (c) is a

hydrocarbylhydrocarbyloxy- silane compound having thestructural formula

H_4-a-b-c-dR¹ _aR² _b(OR³)_c (OR⁴)_dSi where R¹, R², R³ and R⁴ are the same or different andare C₁-C₁₂ alkyl, C₆-C₁₀ aryl, C₇-C₁₄ aralkyl or C₇-C₁₄ alkaryl; a is an integer of 1 to 3; b is 0 or an integer of 1 or 2; c is an integer of 1 to 3 ; and d is 0 or an integer of 1 or 2.

5. A catalyst in accordance with any of Claims 1-4 wherein said catalyst component (d) is a halosilane compound having the structural formula

H_mY_nSiX_4-m-n where Y is alkyl, alkoxy, aryl, aryloxy, aralkyl, aralkyloxy, alkaryl or alkaryloxy; X is halogen; and mand n are the same or different and are 0 or an integer of 1 to 3 with the proviso that m and n cannot both be 0 and that the sum of m and n cannot exceed 3.

6. A catalyst in accordance with Claim 5 wherein Yis alkyl; and X is chlorine.

7. A catalyst in accordance with any of Claims 1-6 wherein said catalyst component (a) is characterized by said magnesium-containing agent being a hydrocarbonsoluble magnesium compound and said transition metal- containing agent being a transition metal compound selected from the group consisting of a titanium-, a vanadium- or a zirconium-containing compound.

8. A catalyst in accordance with Claim 7 wherein said hydrocarbon soluble magnesium compound is selected from the group consisting of dihydrocarbyl-magnesium compounds, dihydrocarbyloxymagnesium compounds,

hydrocarbylmagnesium-trihydrocarbylsilyl amides,hydrocarbylmagnesium halides and hydrocarbyloxymagnesium halides and said transition metal compound is an

organotitanium compound or an organovanadium compound.

9. A catalyst comprising:

(a) a solid catalyst component which includes the product of a hydrocarbon soluble magnesium compoundand an organometallic compound wherein the metal of said compound is titanium or vanadium;

(b) an organoaluminum compound;

(c) a hydrocarbylhydrocarbyloxysilane compound having the structural formula

H_4-b-c-dR¹ _aR² _b(OR³)_c (OR⁴)_dSi where R¹, R², R³ and R⁴ are the same or different and are C₁-C₁₂ alkyl, C₆-C₁₀ aryl, C₇-C₁₄ aralkyl or C₇-C_ι4alkaryl; a is an integer of 1 to 3; b is 0 or an integer of 1 or 2; c is an integer of 1 to 3 ; and d is 0 or an integer of 1 or 2; and

(d) a halosilane compound having the structural formula

H_mY_nSiX_4-m-n where Y is alkyl, alkoxy, aryl, aryloxy, aralkyl, aralkyloxy, alkaryl or alkaryloxy; X is halogen; and mand n are the same or different and are 0 or an integer of 1 to 3, with the provisos that m and n cannot both be 0 and that the sum of m and n cannot exceed 3.

10. A catalyst in accordance with any of Claims 1-9 wherein the molar ratio of said component (b) to said component (c) is at least about 10.

11. A catalyst in accordance with any of Claims 1-

10 wherein the molar ratio of said component (c) to said component (d) is at least about 1.

12. A catalyst in accordance with any of Claims 1-

11 wherein the molar ratio of said component (c) to said component (d) is at least about 2.5.

13. A catalyst in accordance with any of Claims 9-

12 wherein said catalyst component (a) is prepared by the steps of:

(1) contacting a first modifying compound selected from the group consisting of silicon halides,boron halides, aluminum halides, alkyl silicon halides and mixtures thereof with at least one hydrocarbon soluble magnesium compound selected from the group consisting of dihydro-carbyloxymagnesium compounds, hydrocarbyloxy-magnesium halides and mixtures thereof;and

(2) contacting the product of step (a) with a titanium-containing compound having the structural formula

TiX² _q(OR⁶)_4-q where X² is halogen; R⁶ is hydrocarbyl; and q is an integer of 1 to 4.

14. A catalyst in accordance with any of Claims 9-

13 wherein said contacting step (1) occurs on an

inorganic oxide support and wherein said sequence of contact of said first modifying compound and wherein said hydrocarbon soluble magnesium compound with said inorganic oxide is random.

15. A catalyst in accordance with any of Claims 9-

14 including step (1a), the step of contacting the product of step (a) with a second modifying compound having the structural formula selected from the group consisting of

SiH₄X³ _{4 - r} where X³ is halogen; and r is an integer of 1 to 3, and HX³ where X³ has the meaning given above, prior to said contacting step (2).

16. A catalyst in accordance with any of Claims 9-

15 including step (1a), the step of contacting the product of step (1) with a second modifying compound having the structural formula selected from the group consisting of

17. A catalyst in accordance with any of Claims 9-

16 comprising step (1b) the step of contacting the product of step (1) with a transition metal-containingcompound, said transition metal selected from the group consisting of titanium, vanadium and zirconium.

18. A catalyst in accordance with any of Claims 9-

17 wherein said transition metal compound is selected from the group consisting of a compound having the structural formula Ti(OR⁵)_pX¹ _4-p where R⁵ is hydrocarbyl; X³ is halogen; and p is an integer of 1 to 4, and a compound having the structural formula

V ( OR ⁷ ) _e ( O ) _fX ⁴ _g where R⁷ is hydrocarbyl; X⁴ is halogen; e is 0 or an integer of 1 to 5; f is 0 or 1; and g is 0 or an integer of 1 to 4, with the proviso that the sum of e, f and g is an integer of 2 to 4.

19. A catalyst in accordance with any of Claims 9-

18 comprising step (1b), the step of contacting the product of step (1) with a transition metal compound selected from the group consisting of a compound having the structural formula Ti(OR⁵)_pX¹ _4-p where R⁵ is hydrocarbyl; X¹ is halogen; and p is an integer of 1 to 4, and a compound having the structural formula

V(OR⁷)_e(O)_fX⁴ _g where R⁷ is hydrocarbyl; X⁴ is halogen; e is 0 or an integer of 1 to 5; f is 0 or 1; and g is 0 or an integerof 1 to 4, with the proviso that the sum of e, f and g is an integer of 2 to 4.

20. A catalyst in accordance with any of Claims 9-

19 comprising step (1b), the step of contacting theproduct of step (1a) with a transition metal compound seleoted from the group consisting of a compound having the structural formula Ti(OR⁵)_pX¹ _4-p where R⁵ is hydrocarbyl; X¹ is halogen; and p is an integer of 1 to 4, and a compound having the structural formula V(OR⁷)_e(O)_fX⁴ _g where R⁷ is hydrocarbyl; X⁴ is halogen; e is 0 or an integer of 1 to 3; f is 0 or 1; and g is 0 or an integer of 1 to 4, with the proviso that the sum of e, f and gis an integer of 2 to 4.

21. A catalyst in accordance with any of Claims 9-

20 wherein said transition metal compound is

Ti(OR⁵)_pX¹ _4-p, where R⁵ is alkaryl; and p is 4 and which comprises step (1c), the step of contacting the product of step (1b) with a compound having the structural formula

V(O)_fX⁴ _g where X⁴ is chlorine; f is 0 or 1; and g is an integer of 1 to 4, with the proviso that the sum of f and g is an integer of 2 to 4.

22. A catalyst in accordance with any of Claims 14-21 wherein said inorganic oxide support is silica.

23. A catalyst in accordance with any of Claims 14-22 wherein said silica has a surface area of between about 80 m²/g and about 300 m²/g, a median particle size of between about 20 microns and about 200 microns and a pore volume of between about 0.6 cc/g and about 3.0 cc/g.

24. A catalyst in accordance with any of Claims 14-23 wherein said silica is pretreated to replace surface hydroxyl groups with groups having the

structural formula

25. A catalyst in accordance with any of Claims 14-24 wherein said pretreatment step comprises calcining said silica in an inert atmosphere at a temperature of at least about 200°C. or treating said silica with a hexaalkyl silazane.

26. A catalyst in accordance with any of Claims 14-25 wherein said pretreatment step comprises calcining said silica in an inert atmosphere at a temperature ofat least about 200°C followed by treating said calcined silica with a hexaalkyl silazane.

27. A catalyst in accordance with any of Claims 9- 12 wherein said solid catalyst component (a) is preparedby the steps of:

(1) disposing an organomagnesium compound having the structural formula

MgR⁸R⁹ where R⁸ and R⁹ are the same or different and are hydrocarbyl, upon an inorganic oxide support;

(2) treating said product of step (1) with a gaseous halogenating compound having the structuralformula

ZX⁵ where Z is hydrogen or chlorine; and X⁵ is chlorine;

(3) contacting the product of step (2) with a

C₁ to C₆ alkanol;

(4) contacting the product of step (3) with a titanium-containing compound having the structural formula

TiX² _q(OR⁶)_4-q where X² is halogen; R⁶ is hydrocarbyl; and q is an integer of 1 to 4; and (5) contacting the product of step (4) with a compound having the structural formula

where Y¹ and Y² are the same or different and arechlorine; bromine, C₁ to C₁₀ alkoxy or taken together are oxygen.

28. A catalyst in accordance with Claim 27 wherein R⁸ and R⁹ are the same or different and are C² to C₁₀alkyl; inorganic oxide support is silica; Z is hydrogen; said C₁ to C₆ alkanol is ethanol; said titanium- containing compound is titanium tetrachloride; and Y¹ and Y² are both n-butoxy.

29. A catalyst in accordance with any of Claims 9- 12 wherein said solid catalyst component (a) is prepared by the steps of:

(1) contacting an organosilicon compound having the structural formula selected from the groupconsisting of

(R¹ ₀₃Si)₂NH where R¹⁰ is hydrocarbyl , and

R^{1 0} _gSiX⁶ _{4 - g} where R¹⁰ has the meaning above; X⁶ is a group reactive with hydroxyl groups on the surface of an inorganic oxide; and g is an integer of 1 to 3, with an inorganic oxide support;

(2) contacting the product of step (1) in random order with an organomagnesium compound selected from the group consisting of R¹¹MgX⁷, where R¹¹ is alkyl, aryl, alkaryl, aralkyl or alkenyl; and X⁷ is halogen, R¹¹R¹²Mg, where R¹¹ has the meanings given above; and R¹² is alkyl, and (R¹¹ ₂Mg)_h.AlR¹¹ ₃, where R¹¹ has the meanings given above; and h is 0.5 to 10 and an alcohol having the structural formula

R¹³OH where R¹³ is C₁-C₆ alkyl, phenyl or benzyl; and

(3) contacting the product of step (2) with a compound having the structural formula

30. A catalyst in accordance with Claim 29 wherein R³⁰ is alkyl, phenyl or alkenyl; X⁶ is halogen, alkoxy, amido or phenoxy; said inorganic oxide support is silica or alumina; R¹¹ is C₁-C₁₀ alkyl, phenyl, naphthyl or cyclopentadienyl; X⁷ is chlorine or bromine; R¹³ is n- butyl or benzyl; X² is chlorine; and q is 4.

31. A process for polymerizing at least one olefin or alpha-olefin which comprises polymerizing at least one olefin or alpha-olefin under polymerization conditions in the presence of the catalyst according to any of Claims 1-30.

32. A process for the polymerization of at least one alpha-olefin which comprises polymerizing an alpha- olefin selected from the group consisting of ethylene and propylene under polymerization conditions in the presence of the catalyst of any of Claims 1-30.