CA1207742A - Polymerization catalyst - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

Catalyst compositions which are particularly useful for the preparation of ethylene polymers having a narrow molecular weight distri-bution are obtained by (1) drying an inorganic oxide having surface hy-droxyl groups, e.g., silica, alumina, magnesia, etc., to remove adsorbed water, (2) reacting the surface hydroxyl groups with at least a stoichio-metric amount of an organometallic compound having at least one alkyl group attached to a Group III metal, e.g., a trialkylaluminum, (3) react-ing the thus-treated inorganic oxide with a vanadium halide, such as (a) VOCl3, VOBr3, and/or mono-, di-, and/or trihydrocarbyloxy derivatives thereof and/or (b) VCl4, VBr4, and/or mono-, di-, tri-, and/or tetrahy-drocarbyloxy derivatives thereof, and (4) reacting that reaction product with at least about 0.1 mol, per mol of organometallic compound, of an alcohol containing 1 to 18 carbon atoms.

Description

- ~ 6/26/82 PJH
~2~ 2 POLYMERIZATION CATALYST

BA~KGROUND 0F THE INVENTION
, Field of the Invention This invention relates to the polymerization of olefins and more particularly relates ~o catalyst compositions useful for poly-merizing one or more monomers comprising ethylene to polymers having a narrow molecular weight distribution and a good balance of physical properties.
Description of the Prior Art 10It is known that catalysts of the type variously described as coordination, Ziegler, Ziegler~type, or Ziegler~Natta catalysts are useful for the polymerization of olefins under moderate conditions of temperature and pressure. It is also known that the properties of the polymers obtainable by the use of such catalysts, as well as the rela-tive economies of the processes used to prepare the polymers, vary with several factors, including the choice of the particular monomers~
`~ catalyst components, polymerization adjuvants, and other polymeriza- tion conditions employed.
During the years since Ziegler catalysts were first publicly disclosed, there has been a considerable amount of research conduc~ed on the use of such catalysts; and numerous publications have resulted from that research. These publications have added much to the know-ledge of how to make various types of olefin polymers by various types of processes. However, as is apparent from the amount of research on Ziegler catalysis that is still being conducted throughout the world, as -~ 6/26/82 PJH
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well as the number of patents that are s~ill being issued to inventors working in the field of Ziegler catalysis, the means of attaining cer-tain results when polymerizing olefins with Ziegler catalysts are still frequently unpredictable The fact that this situation exists is some-times due to the need to obtain a previously-unattainable combination of results; occasionally due to difficulties in obtaining the same results in a commercial-scale apparatus as in a labora~ory-scale reactor; and often due to a polymerization parameter's having an effect, or side-effect, in a given type of polymerization process ~hat is different from effects achieved by its use in prior art processes of a different type.
One aspect of Ziegler catalysis in which the need for fur-ther research has been found to exist has been in the field of prepar-ing ethylene polymers having a narrow molecular weight distribution and a good balance of physical properties. Such polymers have particu-lar application in the production of articles that are formed by in-jection molding; typically have molecular weight distributions such that their normalized V30jV30~ melt viscosity ratios are in the range of about 1.5 to 2.3, with the ratios in the lower portion of this range being generally preferred but difficult to attain with known processes that might otherwise be commercially feasible; and - like other polymers intended for commercial use - are desirably prepared by a process which is as economical as possible as well as being capable of producing a polymer having the desired properties.
There are, of course, known processes for preparing injec-tion molding resins by pol~merizing ethylene with the aid of Zieglercatalysts. ~owever, the known processes typically suffer one or more : ~, 55~8 P~J}I

of the disadvantages of lack of economy, inability to produce polymers having a suitable balance of properties, and/or unreliability in pro-ducing such polymers - particularly in commercial-scale operations.
What is still needed is a catalyst which (a) is suitable for use in a S gas-phase polymerization process 9 (b) is capable of yielding polymers having a narrow molecular weight distribution and a good balance of physical properties, and ~c) has sufficient activity to be economically attractive.
British Patent 1,489,410 (Monsanto) teaches gas-phase poly-merization processes which, because of their use of supported Ziegler catalysts having a vanadium component and other factors, are commer-cially attractive processes. However, as taught in the patent, the processes are designed to result in the formation of polymers having the broad molecular weight distributions suitable for blow molding IS resins rather than the narrower molecular weight distributions needed for injection molding resins; and the patent itseli does not suggest how its processes might be modified ~o result in the formation of polymers having narrower molecular weight distributions. Attempts to make the processes of the patent suitable for the preparation of in-jection molding resins by combining its ~eachings with the teachings ofpublications that discuss means of narrowing molecular weight distribu-tion have not been successful. For e~ample, polymers having a suffi-ciently narrow molecular weight distribution have not been obtained when Monsanto's preferred vanadium halides have b~en replaced with the alkoxy group-containing vanadium compounds which are within the scope of their patent and which U. S. patents 3,457,244 (Fukuda et al.) and 556g PJH
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3,655,583 (Yamamoto et al.) teach to result in the production of poly-mers having narrower molecular wPight distributions when unsupported catalyst systems are employed.
Fukuda et al. also teach that ethylene copolymers or ter-polymers having narrow molecular weight distributions can be obtainedby the use of an unsupported catalyst composi~ion prepared by (l) mix-ing an alcohol containing l to 12 carbon atoms with VOC13 and then (2) mixing the mixture thus obtained with an alkylaluminum compound in the presence of the monomers to be interpolymerized, and there are other patents, e.g , Stamicarbon's British patent l,l75,5g3 and U. S patents

2,535,269 (Tanaka et al.~, 4,071,674 (Kashiwa et al.), and 4,256,865 (Hyde et al.) which teach the use of catalyst compositions prepared by adding an alcohol at some stage during the catalyst preparation. How-ever5 although some of these patents are concerned with the production of polymers having narrow molecular weight distributions, none of them teaches a catalyst composition which satisfies the aforementioned need for a catalyst suitable for use in a commercially-at~ractive gas-phase polymerization process that is capable of producing injection molding-grade polymers having a good balance of physical prope~ties.
SUMNARY OF THE INVENTION
An object of the invention is to provide novel catalyst com-posltions useful for the polymerization of olefins.
Anothex object is to provide such catalyst compositions us~ful in an economical gas-phase process for polymerizing one or more monomers comprising ethylene to polymers having a narrow-to-intermediate molecu-lar weight distribution and a good balance of physical properties.

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Still another object is to provide processes for preparing such catalyst compositions.
A further objec~ is to provide olefin polymerization pro-cesses utilizing the novel catalyst compositions.
These and other objects are attained by:
(A) preparing a catalyst composition by:
(1) drying an inorganic oxide having surface hydroxyl groups to form a suppor~ that is substantially free of adsorbed water, (2) reacting the surface hydroxyl groups of the sup-port with a~ least a substantially stoichiometric amount of at least one organometallic compound corresponding to the formula RXMR'yRl~z~ whereiI- M
is a metal of Group III of ~he periodic table, R is an alkyl group con ; taining 1 to 12 carbon atoms, R' and R" are independently selected from the group consisting of H, Cl, and alkyl and alkoxy groups containing 1 : 15 to 12 carbon atoms, x has a value of 1 to 3, and y and z both represent values of 0 to 2, the sum of which is no~ greater than 3-g,

(3) reacting the thus--treated support with at least about 0.001 mol, per mol of organometallic compound, of at least one vanadium compound corresponding to a ormula selected from (RO)nVOX3_n and (RO)mVX4 ~, in which formulas R represents a Cl C18 monovalent hy-drocarbon radical that is free of aliphatic unsaturation, ~ is Cl or Br, n has a value of 0 to 3, and m has a value of 0 to 4, and

(4) reacting the product of step 3 with at least about 0.1 mol, per mol of organome~allic compound, of an alcohol con-; 25 taining 1 to 18 carbon atoms and (B~ whe~ desired, polymerizing a monomer charge compris-` 6/26/82 PJH
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ing ethylene in contact with the catalyst composition thus prepared.DETAILED DESCRIPTION
The inorganic oxidP used in preparing a catalyst composition of the invention may be any particulate inorganic oxide or mixed oxide, e.g. 3 silica, alumina, silica-alumina, magnesia, zirconia, thoria, ti-tania, etc., having surface hydroxyl groups capable oF reacting with the organometallic compou~d. However, it is generally an inorganic oxide selected from the group consisting of si]ica, alumina, magnesia, and mixtures thereof, i.e., physical mixtures, such as mixtures of silica and alllmina particles9 etc. 9 andtor chemical mixtures, such as magnesium silicate, aluminum silicate, etc. The suxface hydroxyl groups may be at the outer surfaces of the oxide particles or at the surfaces~ of pores in the particles, the only requirement in this re~
~ gard being that they be available for reaction with the organometallic `~ 15 compound.
The specific particle size, surface area, pore volume, and number of sur~ace hydroxyl groups characteristic of the inorganic ox-~ide are not critical to its utility in the practice of the invention.
However, since such characteristics determine the amount of inorganic oxide that it is desirable to employ in preparing the catalyst compo-sitions, as well as sometimes affecting the properties of polymers formed with the aid oi the catalyst compositions, these characteric-$ics must frequently be taken into consideration in choosing an inor-ganic oxide for use in a particular aspect of the invention. For ex-ample, when the catalyst composition is to be used in a gas-phase polymerization process - a type of process in which it is known that PJH
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the polymer particle size can be varied by varying the particle size of the support - the inorganic oxide used in preparing the catalyst com-position should be one having a particle size that is suitable for the production of a polymer having the desired particle size. In general, optimum results are usually obtained by the use of inorganic oxides hav-ing an average particl~ size in the range of about 30 to 600 microns, preferably about 30 to 100 microns; a surface area of about 50 to 1000 square meters per gram, preferably about 100 to 400 square meters per gram; and a pore vol~e of about 0.5 to 3.5 cc per gram, preferably about 0.5 to 2 cc per gram.
As indicated above, the organometallic compound that is re-acted with the surface hydroxyl groups of the inorganic oxide in the practice of the invention may be any one or more organometallic compounds corresponding to the formula RxMR'yRt'z, wherein M is a metal of Group III
of the periodic table, R is an alkyl group containing 1 to 12 carbon atoms, R' and R" are independently selected from the group consisting of ~, Cl, and alkyl and alkoxy groups containing 1 to 12 carbon atoms, x has a value of 1 to 3, and y and z both represent values of 0 to 2, the sum of which is not greater than 3 x. Thus, M may be, e.g., aluminum, gallium, indium, or thallium; R may be, e.g., methyl, ethyl, propyl, isopropyl ~ n-butyl, isobutyl, n-pentyl, isopentyl, t-pentyl, hexyl, 2-methylpentyl, heptyl, oc~yl, 2-ethylhexyl~ nonyl, decyl, dodecyl, etc.;
R', when present, may be H, Cl, an alkyl group, such as one of those exemplified above for R, which is the same as or different from R, or an alkoxy group; such as the alkoxy groups corresponding to the aforemen-tioned alkyl groups; and R", when present, may be any of the substituents 6l26/~2 P~H
~2~

mentioned above as exemplary of R' and may be the same as or different from R'.
The preferred organometallic compounds are those in which N
is aluminum. Utilizable aluminum compounds include chlorides, such as dimethylaluminum chloride, diethylaluminum chloride, dipropylaluminum chloride, diisobutylaluminum chloride, the corresponding alkylaluminum dichlorides, etc., and mixtures of such chlorides, but the chlorides are generally not particularly preferred because of the halogen resi-due they con~ribute to polymers made in their presence. The more pre-ferred aluminum compounds are the trialkylaluminums, dialkylaluminumhydrides, dialkylaluminum alkoxides, and alkylaluminum dialkoxides, such as trimethylaluminum, triethylaluminum, tripropylaluminum, tri-butylaluminum? triisobutylaluminum, isopropenylaluminum, trihexylal~mi-num, trioctylaluminum, tridecylaluminum, tridodecylaluminum, etc.; the corresponding alkoxy compounds wherein one or two of the alkyl groups have been replaced by alkoxy groups, such as ethylaluminum diethoxide, diethylaluminum ethoxide, ethylaluminum sesquiethoxide, ethylalumi~um diisopropoxide, etc.; diethylaluminum hydride, di-n-propylaluminum hydride, diisobutylaluminum hydride, etc.; and mixtures of such com-pounds.
Especially preferred aluminum compounds are the trialkylalu-minums, particularly triethylaluminum and tri-n-hexylaluminum, which are advantageous to employ because of their cost, availability, and/or effectiveness. Whe~ a trialkylaluminum is used as the organometallic compound, it is generally found that - all other factors being con-stant - the molecular weight distributions of polymers prepared with P~rH
~77~
the catalysts of the invention are narrowed as the chain lengths of the alkyl groups of the trialkylaluminwn are lengthened.
The amount of organometallic compound employed is at least subs~antially the stoichiometric amount, i.e., the amount required to react with all of the available hydroxyl groups on the inorganic oxide.
Use of an amount less than the substantially stoichiometric amount would broaden the molecular weight distributions of polymers formed in the presence of the catalyst composi~ions; use of an amount greater than the substantially stoichiometic amount is permissable within the scope of the invention but frequen~ly serves no practical purpose and can be disadvantageous in that the excess oxganometallic compound some-times leads to fouling of the polymerization reactor if not removed from ; the catalyst composition prior to the composition's being used.
When the number of available hydroxyl groups on the particu-lar inorganic oxide being treated is not known3 it can be determinedby any conventional technique, e.g., by reacting an aliquot of the in-organic oxide with excess triethylaluminum and determining the amount of evolved ethane. Once the number of available hydroxyl groups on the inorganic oxide is known, the amount of organometallic compound to be employed is chosen so as to provide at least about one mol of organo-metallic compound per mol of available hydroxyl groups.
The vanadium component of the catalyst compositions of the invention may be a~y one or more compounds corresponding to a formula selected from (R0)nVOX3_n and (RO)mVX4 m~ wherein R represents a mono-valent hydrocarbon radical that contains 1 to 18 carbon atoms and isfree of aliphatic unsaturation, X is Cl or Br, n has a value of 0 to 3, .

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and m has a value of O to 4. Thus, the utilizable vanadium compounds include VOC13, VOBr3, and the indicated mono-, di-, and trihydrocax-; byloxy derivatives thereof, as well as VC14, VBr4, and the indicated mono-, di-, tri-, and tetrahydrocarbyloxy derivatives ther~of; and R, ; 5 when present, may be a straight- or branched-chain alkyl, cycloalkyl, aryl, alkaryl, or aralkyl group, such as methyl, ethyl~ propyl, iso-propyl, butyl, isobutyl, pentyl, hexyl~ cyclohexyl, heptyl, octyl, cy-clooctyl, nonyl, decyl, dodecyl, hexadecyl, octadecyl, phenyl, benzyl, dimethylphenyl, ethylphenyl, e~c. When mixtures of vanadium compounds are employed, the vanadium component may be a mixture of two or more com-pounds corresponding to either of the general formulas given above or a :mixture of one or more compounds corresponding to one of those general formulas with one or more compounds corresponding ~o the other of those general formulas.
lS Ordinarily, when a vanadium compound of ~he (RO)nVOX3 n type is employed, it is preferably a compound wherein X is Cl because of the greater availability of such compounds; and it is preferably a monoalkoxy compound, since (1) all other factors being ccnstant, the use of VOC13 or VOBr3 in the preparation of the catalyst compositions ~0 of the invention does not permit the attainment of as narrow a molecu-lar weight distribution as can be obtained when the polymerization re-actions of the invention are conducted in the presence of the catalyst compositions that ar prepared by the use of the hydrocarbyloxy deriva-tives of VOC13 or VOBr3 and (2) the use of hydrocarbyloxy derivatives other than the monoalkoxy compounds does not appear to offer advantages that would compensate for the greater difficulty and cost of obtaining 556~
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them. Thus, considering both cost and effectiveness in the practice of the inven~ion, ~he preferred (RO)nVOX3 n compounds are those com-pounds in which R is alkyl, X is Cl, and n has a value of about 1.
Ordinarily, when a vanadium compound of the (RO)mVX4 m type is employed, it is preferably VC14 or a derivative thereof, most pref-erably VCl~ itself. The use of VC14 in the preparation of catalyst compositions of the invention leads to the formation of compositions which are so satisfactory in the production of injection molding-grade ethylene polymers that there is seldom any reason to use a more expen-sive (RO)mVX4 m compound instead of it.
The amount of vanadium compound(s) employed in the practiceof the invention may be varied considerably bu~ is generally such as to provide at least about O.OOl mol of vanadi~m compound per mol of or-ganometallic compound. When the catalyst composition is to be pre-pared by the preferred process described below, wherein no washingstep is utilized during or after preparation of the compositions, the amount of vanadium compound employed should not be substantially in excess of the amount capable of reacting with the treated support, i.e., about 1 mol of vanadium compound per mol of organometallic com-~O pound. Use of a greater amount would serve no practical purpose andcould be disadvantageous in that the excess vanadium compound could lead to fouling of the polymerization reactor. ~owever, a larger amount of van~dium compo~md may be employed when fouling of the reac-tor is not expected to be a problem and/or excess vanadi~m compound will be removed from the catalyst composition before the composition is used. In the practice of the invention, the amount of vanadium ' 11 ~A` ~ 5568 PJH
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compound employed is generally not in excess of about 3 mols per mol of organometallic compound; and excellent results are obtained by the use of about 0.03 to 0.2 mol of vanadium compound per mol of organometallic compound, i.e., about 5 to 30 mols of organometallic compound per mol of vanadium compound.
As indicated above, the alcohol employed in preparing the present catalyst compositions may be any alcohol containing 1 to 18 carbon atoms; and it may be conveniently defined as a compound corre-spo~ding to the formula ROH, wherein R may be any of the groups, or types of groups, mentioned above as exemplary of the R groups of the utilizable hydrocarbyloxy compounds.
When the vanadium compound, or one of the vanadium compounds~
employed in the practice of the invention is a hydrocarbyloxyvanadium compound that ~he catalyst manufacturer will synthesize for that use, it is frequently desirable, as a matter of convenience3 to employ an alcohol component identical to the alcohol required to synthesize the desired hydrocarbyloxyvanadium compound~ However, it is not necessary for the R group of the alcohol to correspond to the R group of any hy-drocarbyloxyvanadium compound being used to prepare ~he catalyst com-position; and, in fact, correspondence of the R groups could be undeosirable in some instances.
For example, if a practitioner of the invention wanted to use ethoxyvanadiu~ oxydichloride as his vanadium compound but also wanted to prepare a catalyst composition that would provide the nar-rowest possible molecular weight distribu~ion in polymers formed inits presence, it would be more desirable for him to use a long-chain ~ 5568 - ` 6/26/~2 PJH
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alcohol, rather than ethanol, as the alcohol, because all other factors being constant, the molecular weight ~istribution is narrowed as the chain length of the alcohol is increased. Increasing the chain length of the hydrocarbyloxy group also tends to narrow the molecular weight distribution.
The preferred alcohols are primary alcohols, with n-alkanols containing 6 to 18 carbon atoms being particularly preferred.
The amount of alcohol used in preparing the catalyst compo-sitions of the invention should be at least about 0.1 mol per mol of organometallic compound employed. There is no maximum amount of alcohol - that may be utilized, but its beneficial effeets begin decreasing when an optimum amount is exceeded, so it is generally not used in excess of 10 mols per mol of organome~allic compound. Ordinarily, the amount of alcohol utilized in the practice of the invention is in the range of about 0.2 to 3, preferably about 0.3 to 1, most preferably about 0.35 to 0.7, mols per mol of organometallic compound.
As indicated above1 the catalyst compositions of ~he invention are prepared by drying the inorganic oxide, reacting the dried inorganic oxide with the organometallic compound, reacting the thus-treated support with the vanadium compound, and then reacting that reaction product with the alcohol. The conditions under which the inorganic oxide are dried are not critical as long as they are adequate to provide an inorganic oxide that has surface hydroxyl groups and is substantially free of adsorbed water. However, it is ordinarily preierred to dry the inorganic oxide at about 100-1000C., with or without a nitrogen or other inert gas purge, until substantially all adsorbed water is removed. Also, although _ 5568 6/26l82 PJH

improved results are obtained by the use of the catalyst compositions of the invention, regardless of the particular temperature at which the inorganic oxide is dried~ the drying temperature has been found to have a negligible-to-noticeable effect on those results - optimum results generally being obtained when the inorganic oxide has been dried at about 200-600C., but drying temperatures of about 500-600C. generally being reguired for optimum results when the inorganic oxide is alumina. The time required for drying of the inorganic oxide varies, of course, with the particular drying t~mperature used but is usually in the range of about 5-16 hours.
When the inorganic oxide has been substantially freed of ad-sorbed water, its surface hydroxyl groups may be reacted with the or-ganometallic compound in any suitable manner, conveniently by (1) adjust-ing its temperature, if necessary, to the tempera~ure at which the reac~
tion with the organometallic compound is ~o be conducted~ t2) slurrying it in an inert liquid hydrocarbon, generally a C4-C8 hydrocarbon, such as isobutane, pentane, isopentane, hexane, cyclohexane, heptane, isooctane, etc., and mixtures thereof with one another and/or with other materials commonly present in commercial disti]lation cuts having the desired boil-ing range, (3) adding a substantially stoichiometric amount Df the or-ganometallic compound in neat or solution form, and ~4~ maintaining the organometallic compound in intimate contact with the inorganic oxide, e.g., by agitating the slurry, for a time sufficient to ensure substan-tially complete reaction wi~h the available hydroxyl groups, generally at least about 5 minutes. The reaction may be conducted with or without pressure and at ambient or reflux temperatures, depending on the particu-~Z~774~

lar organometallic compound employed, as will be readily understoodby those skilled in the art. When -the organometallic compound is added in solution form, it is generally preferred, though not required, that the solvent be the same inert li~uid hydrocarbon as is already present in the slurry.
The reaction of the vanadium component with the treated support may also be accomplished by conventional means, such as any of the techni~uès described in British Patent 1,489,410.
However, it is most desira~ly accomplished simply by adding the vanadium compound in neat or solution form to the slurry of treated support and maintaining it in intimate contact with the treated support for a time sufficient to provide for substantially com-plete reaction, usually at least about 5 minutes and preferably about 10-60 minutes, although, actually, the reaction is virtually instantaneous.
When reaction of the vanadium component with the treated support has been completed, reaction with the alcohol may be accomplished in any suitable manner, conveniently just by adding the alcohol to the vanadium component/treated support reaction product and maintaining it in contact therwith, e.g., by agitating the slurry, for a time sufficient to ensure substantial completion of the desired reaction, usually at least about 5 minutes and most commonly about 30-60 minutes. All that is critical about the manner in which the alcohol is reacted with the other catalyst components is the time at which it is added to the system. Reaction of the other components with one another must be substantially 5S6~

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complete before the alcohol is added in order for the catalyst composi-tions to have the desired performance capabilities.
After the alcohol has been reacted with the other catalyst com-ponents, the resultant catalyst composition may or may not require fur-ther treatment to make it suitable for use, depending on th~ particularprocess that has been used to prepare the catalysk composition and the particular type of polymerization process in which i~ is to be used. For example, if the catalyst composition has been prepared by a type of pro-cess which results in its being already dry when reaction with the alco-hol has been accomplished, no further ~reatment is likely to be necessaryif the composition is to be used in a gas-phase polymerization process;
~but slurrylng of the composi~ion in a suitable liquid medium may be de-sirable if it is to be used in a slurry or solution polymerization pro-cess. On the other hand, if the catalyst composition has been prepared by the preferred process described above, i.e., if the inorganic oxide has been slurried in a liquid medium prior to the addition of the other components, it is already suitable for use in a slurry or solution poly-merization process but will have to be dried to make it suitable for use in a gas-phase polymerizatio~ process. Whe~ the composition is to be dried, i.e., freed of any liquid medium used in its preparation, the dry-ing may be achieved by any conventional technique, e.g., filtration, cen-trifugation, evaporation, blowing with nitrogen, etc.
Regardless of the particnlar technique used to prepare the catalyst compositions of the invention, it should be kept in mind that they are Ziegler catalysts and are therefore susceptible to poisoning by the materials, such as oxygen, water, etc., ~hat are known to reduce or PJH
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destroy the effectiveness of Ziegler catalysts. Accordingly, they should be prepared, stored, and used under conditions that will permit them to be useful as polymerization catalysts, e.g., by the use of an inert gas atmosphere, such as nitrogen.
Use of the catalyst compositions of the invention does not re-quire any modifications of known techniques for the polymerization of ethylene, with or without comonomers. Thus, the polymerization may be conducted by a solution, slurry, or gas-phase technique9 generally at a temperature in the range of about 0-120C. or even higher, and under at-mospheric, subatmospheric, or superatmospheric pressure conditions; and conventional polymerization adjuvants, such as hydrogen, haloalkanes, etc., and conventional catalyst concentrations, e.g., about 0.01-5% by weight of monomer, may be employed if desired. However, it is generally preferred to use the catalyst compositions at a concentration such as to provide about 0.000031~0.005%, most preferably about 0.00001-0.0003%, by weight of vanadium, based on the weight of monomer(s), in the polymeriza-tion of ethylene, alone or with up to about 50%, based on the weight of total monomer, of one or more higher alpha-olefins, in a gas-phase poly-merization process utilizing superatmospheric pressures, temperatures in the range of about 65-115C., and hydrogen and haloalkane adjuvants.
Comonomers, when employed, are generally alpha-olefins con-taining 3-12 carbon atoms, e.g., propylene, butene-l, pentene-l, 4-methylpentene-l, hexene-l, heptene-l, octene-l, nonene-l, decene-l, dodecene-l, etc., and mixtures thereof.
The invention is particularly advantageous in that it provides catalyst compositions which (1) have the active ingredients ' " 6/2~/82 PJH
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chemically-attached to an inorganic oxide support, (2) are capable of producing ethylene polymers having a narrow-to-intermediate molecular weight distribution, as desired, and a good balance of physical proper-ties by an economical gas-phase process that gives a high yield of polymer and (3) can also be used to prepare such polymers by slurry or solution processes. The fact that high yields of polymer can be obtained by the use of the catalyst compositions is particularly une~pected in that these high yields are attainable even when the catalyst compositions are prepared by the preferred process wherein no washing step is required or utilized during or after preparation of the compositions. Both experience in the field and the tea~chings of the prior art indicate that at least one washing step should be required in the preparation of such compositions when high yield catalysts are desired.
The following examples are given to illustrate the invention and are not intended as a limitation thereof. In these examples, com-positions and processes that are illustrative of the invention are distinguished from those that are outside the scope of the invention and are included only for comparative purposes by using an alphabetic designation for any Run # tha~ is a comparative example and a numeric designation for the examples that are illustrative of the invention.
Yields given in the examples are measures of productivity in terms of the number of grams of polymer produced per 0.4 gram of catalyst per hour, melt indices (MI2) are those determined by ASTM test D-123S-65T using a 2160-gram weight, while the NVR values are "normalized" melt viscosity ratios determined by (1) measuring the apparent viscosities of the polymers at 30 sec 1 and 300 sec. 1, respectively~ at 200C. in an "~;j,,~, 556g PJ~I
~I77~2 Instron capillary rheometer and (2) normali2ing them ~o V30 = 5 by the equation:
NVR = antilog (0.14699 -~ 0.7897 log V30 - log V300) where V30 and V300 are the measured apparent viscosities. This nor-malization permits comparison of the viscosity ratios of polymers havingdifferent V30 values, since the unnormalized V30/V300 ratio is a function of V30. The NVR is constant for any given catalyst over an MI2 range of about 1-3G, and only slight deviations occur outside of that range.
In the examples, t~he following procedures are used to prepare the catalyst compositions and polymers.
PREPARATION OF CATALYSTS
In the preparation of each of the catalysts, dry a co~mercial inorganic oxide by heating it under dry, deoxygenated nitrogen for 5-16 hours at a temperature of 200-600C. to provide an activated oxide containing about 1-1.4 nmols of available hydroxyl groups per gram. Cool the activated oxide to ambient temperature under a purified nitrogen blanket, suspend it in commercial hexane, add neat organometallic compound, and stir the resultant slurry for 30-60 minutes. Then add a vanadium compound in neat or solution form~ stir the resultant slurry for an additional 30-60 minutes, add an alcohol, stir for another 30-60 minut~s, and remove the hexane under a nitrogen purge to produce a powdered solid catalyst. The particular ingredients used to prepare the catalysts, the amounts of organometallic, vanadium, and alcohol compounds added per gram of inorganic oxide, and the particular temperatures used to dry the inorganic oxides are shown in the examples and/or tables.

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lZ~7742 Throughout the examples the commercial magnesium oxide used is Merck Maglite D, an inorganic oxide having a surface area of about 150-200 square meters per gram, a pore volume of about 1.2-1.5 cc per gram, and an average particle size of about 30-40 microns; the commercial silica employed is Davison 952 silica gel, an inorganic oxide having a snrface area of about 250-350 square meters per gram, a pore volume of about 1.5 1.7 cc per gram, and an average particle size of about 65-75 microns; the commercial alumina is Norton 6376, an inorganic oxide having a surface area of more than 100 square meters per gram and a pore volume of about 0.8-1.1 cc per gram; and the commercial aluminum silicate a~d magnesil~ silicate are W. R. Grace's materials haviug the designations XSZ-AL-65C and XSZ-NG-66C, respectively.
SLURRY POLYMERIZATION
; Charge 1.5 liters of dry hexane to a suitable autoclave under a dry9 deoxygenated nitrogen atmosphere, add 2.1 mmols of triethylaluminum as an activator-scavenger3 stir for 5 minutes, and add a slurry of 0.1-0.4 gram of catalys~ powder in, respectivel~g 1-4 ml of commercial hexane. Raise the temperature of ~he reactor to 85-90C., add enough hydrogen to ensure the production of a polymer having a molecular weight such that its MI2 will be within the range of about 1-30, raise the reactor pressure to about 2.1 MPa with ethylene and any comonomer{s) being employed, and hold the pressure at that level throughout the polymerization by adding monomer as needed. Immediately after pressurizing the reactor with monomer, add 0.17 mmol of chloroform as a promoter; and, at 15-minute intervals thereafter, add supplemental 0.17 mmol aliquots of the promoter. After one hour, stop the polymerization - ~ t~emar~ 20 .~ 5568 -- ~ 6/26/82 PJH

~Z~;B7~Z
by venting the autoclave, opening the reactor, and filtering the polymer from the liquid medium. Then dry the polymer under vacuum at 60C. for 4 hours.
~JAS-PHASE POLYMERIZATION
Charge the catalyst powd~r to a vertical cylindrical reactor adapted to contain a fluidized bed of catalyst and product particles and to permit the separation and return of entrained particles in unreacted gas by the use of a disengaging zone of larger diameter at the top of the bed.
Introduce a stream or streams of ethylene, any comonomer(s) 9 chloroform, and hydrogen to the reactor. Continuously withdraw unreacted or recycle gas from the top of the disengaging zone, pass it through a heat exchanger to maintain a bed temperature of about 95-100C., and introduce it at the bottom of the reactor at a rate sufficient to give a superficial velocity of about 25 cm/sec in the bed.
Introduce make-up monomer, chloroform9 and hydrogen into the recycle gas line so as to maintain the reactor pressure at about 3.5 MPa and to provide about 40 Immols of chloroform per mmol of vanadium per hour, and feed fresh catalyst particles into the reactor below the top of the bed so as to provide a vanadium feed rate of one mmol per hour. Add triethylaluminum as a scavenger and supplemental activator during the ; polymerization so as to provide a triethylaluminum feed rate of 20 mmol per hour. Withdraw polymer product semi-continuously from the bottom of the bed at a rate such as to maintain a constant bed level. Take aliquots of withdrawn polymer for testing.

:, -~ 21 .. ~ 5568 PJH
'74;~
EXANPI,E I
Prepare five catalyst compositions by the catalyst preparation proced~re de~cribed above, except for using no alcohol in the preparation of the first composition. In each case, ernploy MgO as thP inorganic oxide, triethylaluminum as the organometallic compound, ethoxyvanadium oxydichloride as the vanadium compound, and ethanol as the alcohol, when employed; and dry the support at about 200C. Use each of the catalyst compositions to prepare polyethylene by the slurry polymerization procedure described above. The amounts of ingredients employed in the ; 10 production of the catalyst compositions 9 and the yields, melt indices, and normalized viscosity ratios (NVR), i.e., molecular weight distributions, of the polymers are shown in Table X.
ABLE I
Run # Catalyst Composition Yield MI2 N~R_ A (C2H50)VOC12/Al(C2H ~3/MgO 70 g 1.0 2.29 0.2 mmol 1.0 mm501 1 g 1 C2H5oH/(c2HsQ)vocl2/Al(c H )3/MgO 104 g 4.6 2.25 0.2 mmol 0.2 mmol 1.0 ~m501 1 g ~ 2 C2H5oHl(c2H5o)vocl2lAl(c H ) /MgO 85 g 2.5 2.14 : 20 0.5 mmol 0.2 mmol 1.0 ~m5013 1 g 3 C2H50H/(C2H50)~0C12/~l(C2H )3/MgO 30 g 4.1 2.10 1.0 mmol 0.2 mmol 1.4 mm501 1 g 4 C2H50H/(C2H50)VOC12/Al(C H )3/MgO 138 g 4.2 2.06 1.4 mmol 0.1 mmol 1.4 ~m501 1 g As demonstrated above, the addi~ion of ethanol, as the last-added component, with an ethoxyvanadium oxydichloride/triethylaluminum/
magnesium oxide catalyst composition results in the formation of a cata-~r~~ ~ 6/26/82 PJH

lyst compositlon that narrows the molecular weight distribution of poly mers formed in its presence - this narrowing of the molecular weight distribution being progressive as the amount of ethanol used is increased from O.2 to l.O mol per mol of triethylaluminum. The following example S shows that polymers having narrow molecular weight distributions can also be obtained when an alkylaluminum alkoxide is substituted for a trialkylaluminum in the practice of the invention.
EXAMPLE II
Prepare a catalyst composition by ~he catalyst preparation procedure described above, using NgO as the inorganic sxide3 drying it at about 200C., and sequentially reacting with 1.0 mmol of diethylaluminum ethoxide, O 2 mmol of ethoxyvanadium oxydichloride, and 1.0 mmol of ethanol per gram of silica. When the catalyst composition is used to prepare polyethylene by the slurry polymerization procedure described above 9 the process results in the production of 80 grams of polymer having a melt index of 3.0 and an NVR value of 2.12.
EXAMPLE III
p two CH3oH/(n-cl8H37o)yocl2lAl(c2H5)3lsio2 catalyst compositions by the catalyst preparation procedure described above, employing the same amounts of ingredients in each case~ i.e., 1.5 mmol of triethylaluminum, 0.2 mmol of n-octadecoxyvanadium oxydichloride, and 1.0 mmol of methanol per gram of silica, but using a drying temperature of about 200C. for the silica used in producing the first of ~he compositions and a drying temperature of about 550C. for the silica used in producing the second of the compositions. Then use each of -the catalyst compositions to prepare polyethylene by the slurry PJH
~7~Z

polymerization procedure described above The yields, melt indices, and NVR values of the polymers are shown in Table II.
TABL~ II
Run # Support Drying Temp. Yield MI2 NVR
55 200C. 170 g 5.4 2.34 6 550C. 198 g 4.6 1.99 The preceding example and the following three examples show that the use of different inorganic oxides, different alkoxyl7anadium compolmds, and different alcohols which may or may not have the same chain length as the alkoxy groups of the vanadium compounds employed, as well as the use of different support drying temperatures, are permissable within the scope of the invention and lead to the formation of catalyst compositions that can be used to prepare polymers having narrow-to-intermediate molecular weigh~ distributions. These examples also show that, in general, narrower molecular weight distributions are obtained when the catalysts used in the preparation of ethylene polymers are formed by the use of supports that have been dried at the higher temperatures within the preferred range of drying temperatures taught in the specification.
EXoMPLE IV
C8H170}Il(n-c~Hl70)vocl2l~l(c2lIs)3lsio2 catalYSt compositions by the catalyst preparation procedure described above~
employing the same amounts of ingredien~s in each case, i.e., 1.4 mmol of triethylaluminum, 0.2 mmol of n-octoxyvanadium oxydichloride, and 1.0 mmol of n-octanol per gram of silica, but using different drying temperatures for the silica used in producing each of the compositions, ':,, r~ 6/26/82 PJH
~Z~77~

i.e., 200C., 350C., and 550C., respectively. Then use each of the catalyst compositions to prepare polyethylene by t~e slurry polymeriz~tion procedure described above. The yields, melt indices 9 and NVR values of the polymers are shown in Table III.
TAB~E III
Run ~ Support Drying Temp. Yield MI2 NVR
7 20~C. 55 g 1.8 ~.32 350C. 146 g 2.1 2.41 9 550C. 320 g 20.2 1.95 EXAMPLE V
n C8Hl7oHl(n-cgHl7o)vocl2lAl(c2Hs)3lAl2o3 catalYSt compositions by the catalyst preparation procedure described above, employing the same amounts of ingredients in each case, i.e., 1.4 mmol of triethylaluminum, 0.2 mmol of n-octoxyvanadiu~ oxydichloride, and 1.0 m~ol of n-octanol per gram of alumina, but using a drying temperature of about 2004C. for the alumina used in producing the first of the compositions and a drying temperature of about 550C. for the alumina used in producing the second of the compositions. Then use each of the catalyst compositions to prepare polyethylene by the slurry polymerization procedure described above. The yields, melt indices, and NVR values of the polymers are shown in Table IV.
TABLE IV
Run ~ Support Dryin~ T~mp. Yield MI2 NYR
1~ 200C. 47 g 6.9 2.16 11 550C. 83 g 11.6 1.65 6/26/g2 P~
3~2~7791;~
EXAMPLE VI
8 17~H/(n CBHl7~vOcl2/Al(c6Hl3)3lAl2o3 cataly compositions by the catalyst preparation procedure described above, employing the same amounts of ingredients in each case, i.e., 1.5 m~ol of tri-n-hexylaluminum, 0.2 mmol of n-octoxyvanadium oxydichloride, and 1.0 mmol of n-octanol per gram of alumina, but using a drying temperature of about 200C. for the alumina used in producing the first of the compositions and a drying temperature of about 500C. for the alumina used in producing the second of the composi~ions. Then use each of the catalyst compositions to prepare polyethylene by the slurry polymerization procedure described above. The yields, melt indices, and NVR values of the polymers are shown in Table V.
TABLE V
Run # Support Drying Temp. Yield MI2 NVR
12 200~ 8 g ~ 1.91 13 500C. 355 g 18.6 1.67 As demonstrated above, particularly when Run ~12 of this example is compared with Run #10 of the preceding example, the sub-stitution of a higher trialkylaluminum for a lower trialkylaluminum in preparing the catalyst compositions of the invention can lead to a narrowing of the molecular weight distriblltions of polymers formed in the presence of the catalyst compositions when all other f~ctors are substantially constant.
EXAMPLE VII
Prepare three n-CgH170H/(n-C8H17O)VOCl2/Al(C6H13)3/ g oxide catalyst compositions by the catalyst preparation procedure des-.5568 Pm ~2~77~
cribed above, employing the same amounts of ingredients in each case, i.e., 1.4 rnmol of tri-n-hexylaluminum, 0.1 mmol of n-octoxyvanadium oxydichloride, and 0.25 mmol of n-octanol per gram of inorganic oxide, ~ and drying the support at about 250C. in each case, but using different

- 5 inorganic oxides as the supports, i.e., silica, magnesium silicate~ and aluminum silicate, respectively. Then use each of the catalyst compositions to prepare polyethylene by the slurry polymerization pro-cedure described above. The melt indices and NVR values of the polymers are shown in Table VI.
TABL~ VI
Run # Inorganic Oxide Support MI2 NVR
14 silic~ 1.97 magnesium silicate B.7 1.76 16 aluminum silicate 11.9 1.66 This example shows that mixtures of inorganic oxides are also useful as suppor~s for the catalyst compositions of the invention and can, in fact, be particularly desirable supports.
The following two examples demonstrate that the reaction of the inorganic oxide with substantially less than a stoichiometric amount of the organometallic compound leads to the formation of polymers having broader molecular weight distributions when the catalyst compositions are used in polymerization reactions, and reaction with an amount oi organometallic compound considerably in excess of the stoichiometric amount - although also useful in the preparation of catalyst compositions capable of being utilized in the production of injection molding-grade

6/26/82 P.JH

7~
polymers - offers no NVR advantage over the use of a substantially stoichiometric amount of ~he organometallic compound.
EXAMP~E VIII
Prepare three n C6H130H/(n ClBH370)VOC12/Al(C6 13)3)3/ 2 catalyst compositions by the ca~alyst preparation procedure described above, drying the silica gel at about 200C. in each case and employing the same amounts of alcohol and vanadium cornpound, i.e., 1.0 mrnol of n-hexanol and 0.2 mmol of n-octadecoxyvanadium oxydichloride per gram of silica, but varying the amount of tri-n-hexylaluminum used. Then use each of the catalyst compositions to prepare polyethylene by the slurry polymerization procedure described above. The yields, melk indices, and NVR vallles of the polymers are shown in Ta~le VII.
TABLE VII
Run # mmol AlR3/g S12 Yield MI2 NVR
B 0.8 45 g 1.0 2.54 17 l.S 7~ g 8.3 1.76 1~ 2.25 250 g --- 1.78 EXAMPLE IX
Prepare three n-c8Hl7oHl~n-cg~l7o)vocl2lAl(c2~s~3lsio2 ca~alyst compositions by the catalyst prepara~ion procedure described above, drying the silica gel at about 550C. in each case and employing the same amounts of alcohol and vanadium compound3 i.e., 1.0 mmol of n-octanol and O.2 mmol of n-octoxyvanadium oxydichloride per gram of silica, but varying the amount o~ triethylaluminum used. Then use each of the catalyst compositions to prepare polyethylene by the slurry ~ 6/26/82 PJ:~I

polymerization procedure described above. The yields, melt indices, and NVR values of the polymers are shown in Table VIII.
TAB~E VIII
; Run # mmol AlR3/g Si2 Yield NI2 NVR
C O.g 48 g 4.5 2.58 D 0.8 55 g 1.4 2.78 1~ 1.5 320 g 20.2 1.95 EXAMPLE X
Prepare $wo catalyst compositlons by the catalyst preparakion procedure described above to test the utility of dialkoxyvanadium compounds in the practice of the invention. Use each of the compositions to prepare polyethylene by the slurry polymerization procedure described above. The yields, melt indices, and NVR values of the polymers obtained by the use o~ each of the catalyst compositions are shown in Table IX.
TABLE IX
Run # Catalyst Composition Yield NI2 NVR
C2H OH/tC2HsO)2V0Cl/A~C ~ )3/Mg~ 152 g 31 2.07 ~ l~O5mmol 0.2 mmol 1.0 ~1 1 g 21 C6Hl OH/(Cl~ 7o)2vocllAl(c6H )3/SiO2 281 g 4.7 1.76 1.0 ~ ol ~.1 mmol 1.5 mm~
EXAMPLE XI
Prepare a catalyst composition by the catalyst preparation procedure described above, using silica gel as the inorganic oxide, drying it at about 200C., and sequentially reacting wi~h 1.5 mmol of tri-n-hexylaluminum, 0.1 mmol of vanadium oxytrichloride, and 1.0 mmol of n-hexanol per gram of silica. When the ca~alyst composition is used to prepare polyethylene by the slurry polymerization procedure described 55~8 ~ 6/26/82 PJll ~2~ Z
above, the process results in the produc~ion of 196 grams of polymer having a melt index of 12.5 and an NVR value of 1.86.
EXAMPLE XIII
Prepare three catalyst compositions by the catalyst preparation procedure described above, except for usi~g no alcohol in the preparation of the first composition. In each case, employ SiO2 as the inorganic oxide, triethylaluminum as the organometallic compound, vanadiu~
tetra~hloride as the vanadium compound, and n-hexanol as the alcohol, when employed; and dry the support at about 250C. Use each of the catalyst compositions to prepare polyethylene by the slurry polymerization procedure described above. The number of mmols of tri-ethylaluminum, vanadium tetrachloride, and n-hexanol employed per gram of silica in the production of the catalyst compositions, and the yields, melt indices, and NVR values of the polymers are shown in Table X.
TABIE X
Run # Catalyst Composition Yield M12 NVR
E VC14/Al(C2H5)3/SiO2 2366 g 0.3 2.34 22 Co6H53~H/3Cog/A1(C2Hs)3/SiO2 227 g 1.7 2.17 23 ~6~13H/oc24lAl(~2Hs)3lsio2 1007 8 0.4 2.01 Examples X-XIII demonstrate the utility of vanadium compounds other than alkoxyvanadium oxydichlorides in the practice of the inven-; 25 tion.
EXAMPEE X~V

" 6/26/82 PJH
77~
Prepare aC6H130H/(Cl8H370)vocl2lAl(c6Hl3~3lsi 2 composition by the catalyst preparation procedure described above, employing 1.5 mmol of tri-n-hexylaluminum~ 0.1 mmol of n-octadecoxyva-nadium oxydichloride, and 1.0 mmol of n-hexanol per gram of silica. For comparative purposes, prepare five other catalyst compositions from the same amounts of the same ingredients, and use the same drying temperature for the silica as was used in the preparation of the first of the compositions, but vary the order of addition of the catalyst components to determine the criticality of that order of addition. Then use each of the catalyst compositions to prepare polyethylene by the slurry polymerization procedure described above. The catalyst compositions and the melt indices and NVR values of the polymers are shown in Table XI, which, like the earlier Tables, lists the catalyst components in the reverse order of addition, i.e., the last-added component being the first lS listed as one reads from left to right.
TABLE XI
Run # Catalyst Composition MI2 NVR
24 C~H130H/tCl~37O)vOcl2/Al(c6Hl3)3l 2 9.1 1.69 F (c6Hl3)3lc~Hl3oHl(cl8H37o)vocl2lsio2 ~~~ 2.51 C6H13H/Al(C6H13)3/(ClgH370)VOCl2/Si02 --- 2.gl ( 18 37O)Vo~l2lc6Hl3o~llAl(c6}~l3)3/sio2 0.4 2.44 I (cl8H37o)vocl2lAl(c6Hl3)3lc6Hl3oHl 2 0.2 2.~8 (C6Hl3)3l(cl8H37o)vocl2lc6Hl3oHlsio2 1.5 2.38 As demonstrated above, catalyst compositions prepared from the same components as the catalys~ compositions of the invention do not have the same effectiveness in narrowing the molecular weight distributions of ~l 2~ PJH

polymers prepared in their presence when the catalyst components are combined in a different order.
Each of the preceding examples illustrates the utility of catalyst compositions of the invention in slurry polymerization pro-cesses. The following two examples demonstrate their utility in gas-phase polymerization reactions.
EXAMPLE XV
Use the catalyst composition of Example I, Run #3, to prepare polyethylene by the gas-phase polymerization procedure described above.
The reactio~ temperatures employed for the polymerizations and the melt indices and NVR values of the products are shown in Table XII.
TABLE XII
Run #~e~J~ NI2 g9~. 4C 2.08 26 99C. 7 2.02 27 88C. 6 2.14 28 88C. 3 ~.16 EXA~E XVI
Use the catalyst composition of Example YIII, Run #17, to prepare polyethylene by the gas-phase polymerization procedure described above. The melt indices and NVR values of the products are shown in Table XIII.
TABL~ XIII
Run tt MI~ NVR
29 10.8 1.89 PJ~I
~Z~7~

24.1 1.88 31 7.7 1.85 The foregoing examples illus~rate the utili~y of the invention in the preparation of high density polyethylenes which typically have S densities oi at least 0.965 g/cc. The following examples illustrate its utility in the preparation of ethylene polymers having lower densities.
E ~MPIE XVII
Prepare two catalyst compositious by the catalyst preparation procedure described above, using magnesia as the inorganic oxide in each 10 case ? drying it at about 200C., and sequentially reacting it with 1.4 mmol of triethylaluminum, 0.2 mmol of an alkoxyvanadium oxydichloride, and 1.0 mmol of an alkanol per gram of magnesia. Then use each of the catalyst compositions to prepare an ethylene copolymer by the slurry polymerization procedure described above, employing 30 cc of liquid butene-l as the comonomer in each case. The catalyst compositions and the melt indices, NVR values, and densities of the polymers are shown in Table XIV.
TABLE XIV
Run ~ Catalyst ~ position MI2 ~VR Density 32 c2HsoH/(c2Hso)vocl2/Al(c2H5)3/Ngo 20 2.00 0.960 33 C4HgOH/(C4HgO)V0~12/Al(C2H5)3/MgO 1.4 1.95 ~.956 EXAMP~E XYIII
Prepare two catalyst compositions by the catalyst preparation procedure described above, using silica as the inorganic oxide in each 25 case, drying it at about 550C., and sequentially reacting it with 1.4 mmol of triethylaluminum, 0.2 mmol of an alkoxyvanadium oxydichloride, .
. 33 PJH
~2~74;~:

and 1.0 mmol of an alkanol per gram of silica. Then use each of the catalyst composi~ions to prepare an ethylene copolymer by the slurry polymerization procedure described above, employing 40 cc of liquid butene-l as the comonomer in each case. The catalyst composi~ions and the melt indices, NVR values, and densities of ~he polymers are shown in Table XV.
TABLE XV
Run # Catalyst Composition MI2 NVR Density

8 17oHl(c8Hl7o)~ocl2lAl(c2H5)3lsio2 5~.6 2~05 0.948 : 10 35 ~H3oxl(cl8x37o)vocl~lAl(c2H5)3lsio2 EXAMPEE XIX
Prepare two catalyst compositions by the catalyst preparation pxocedure described above, using alumina as the inorganic oxide in each case, drying it at about 550C. in the case of the catalyst composition to be used in Run #36 and at about 500~C. in the case of the catalyst composition to be used in Run ~37, and sequentially reacting it with 1.5 mmol of a trialkylaluminum, 0.2 mmol of n-octoxyvanadium oxydichloride, and 1.0 mmol of n-octanol per gram of alumina. Th~n use each of the catalyst compositions to prepare an ethylene copolymer by the slurry polymerization procedure described above1 employing 40 cc of liquid butene-l as the comonomer in each case. The catalyst composi~ions and the melt indices, NVR values, and densities of the polymers are shown in Table XVI.
TABLE XVI
Run # Catalyst Composition MI2 NVR Density 55~

PJH

36 C8H170~/~C8H170)VOCl2/Al(C2H5)3tA1203 8 17 /(~8}ll7)~Cl2/Al~CsH13~3/A1203 S7.8 1 53 0 955 EXAMPLE ~X
Use the catalyst composition of Example XIII, Run #23, to prepare an ethylene copolymer by the slurry polymerization procedure described above, employing 100 cc of liquid butene-l as the comonomer.
The process results in the production of 1007 grams of an ethylene/
butene-1 copolymer having an NVR value o~ 2.01 and a density of 0.937.
EXAMPLE XXI
Use the catalyst of Example XI to prepare an ethylene copolymex by the slurry polymerization procedure described above, utilizing 40 cc o liquid butene-l as the comonomer. The process results in the production of 283 grams of an ethylene/butene-l copolymer having an NI2 of 11.4 and an NVR value of 2.17.
Similar resul$s in the narrowing of the molecular weight distributions of ethylene polymers are obtained when the examples are repeated except that the catalyst components, component proportions, comonomers, comonomer proportions, and/or polymerization conditions specified in the examples are replaced with catalyst components, com-ponent proportions, comonomers, comonomer proportions, and/or poly-merization conditions ~aught to be their equivalents in the specifica-: tion.

~- 35

Claims (28)

1. A catalyst composition consisting essentially of the product obtained by:
(1) drying an inorganic oxide having surfac hydroxyl groups to form a support that is substantially free of adsorbed water, (2) reacting the surface hydroxyl groups of the support with at least a substantially stoichiometric amount of at least one organometallic compound corresponding to the formula RxMR'yR"z, wherein M
is a metal of Group III of the periodic table, R is an alkyl group con-taining 1 to 12 carbon atoms, R' and R" are independently selected from the group consisting of H, Cl, and alkyl and alkoxy groups containing 1 to 12 carbon atoms, x has a value of 1 to 3, and y and z both represent values of 0 to 2, the sum of which is not greater than 3-x, (3) reacting the thus-treated support with at least about 0.001 mol, per mol of organometallic compound, of at least one vanadium compound corresponding to a formula selected from (RO)nVOX3-n and (RO)mVX4-m, in which formulas R represents a C1-C18 monovalent hydrocar-bon radical that is free of aliphatic unsaturation, X is Cl or Br, n has a value of 0 to 3, and m has a value of 0 to 4, and (4) reacting the product of step 3 with at least about 0.1 mol, per mol of organometallic compound, of an alcohol containing 1 to 18 carbon atoms.

2. The composition of claim 1 wherein the support is an in-organic oxide selected from the group consisting of silica, alumina, magnesia, and mixtures thereof.

3. The composition of claim 1 wherein the organometallic compound is a compound corresponding to the formula RAlR'R", wherein at least one of the R, R', and R" substituents is an alkyl group containing 1 to 12 carbon atoms and the remaining substituents are independently selected from the group consisting of hydrogen and alkyl and alkoxy groups containing 1 to 12 carbon atoms.

4. The composition of claim 3 wherein the organometallic compound is a trialkylaluminum.

5. The composition of claim 4 wherein the trialkylaluminum is triethylaluminum.

6. The composition of claim 4 wherein the trialkylaluminum is tri-n-hexylaluminum.

7. The composition of claim 1 wherein the vanadium compound is a compound corresponding to the formula (RO)nVOCl3-n.

8. The composition of claim 7 wherein R is alkyl and n has a value of about 1.

9. The composition of claim 7 wherein n has a value of 0.

10. The composition of claim 1 wherein the vanadium compound is a compound corresponding to the formula (RO)mVCl4-m.

11. The composition of claim 10 wherein m has a value of 0.

12. The composition of claim 1 wherein the alcohol is a pri-mary alcohol.

13. The composition of claim 12 wherein the alcohol is an alkanol containing at least 6 carbon atoms.

14. The composition of claim 1 wherein the amounts of mate-rials employed in its preparation are such as to provide, as starting materials, about 5 to 30 mols of organometallic compound per mol of vanadium compound.

15. The composition of claim 1 wherein the amount of or-ganometallic compound reacted with the surface hydroxyl groups of the support is the substantially stoichiometric amount.

16. A process for preparing the catalyst composition of claim 1 which consists essentially of (1) drying the inorganic oxide to remove substantially all adsorbed water, (2) slurrying the dried inorganic oxide in an inert liquid hydrocarbon, (3) adding at least a substantially stoichiometric amount of the organometallic compound to react it with the surface hydroxyl groups of the inorganic oxide, (4) adding the vanadium compound to react it with the treated inorganic oxide, (5) subsequently adding an alcohol containing 1 to 18 carbon atoms, and (6) drying the composition thus formed.

17. The process of claim 16 wherein the inorganic oxide is dried at about 100 to 1000°C. until substantially all adsorbed water is removed and is then cooled to ambient temperature before being slurried.

18. The process of claim 17 wherein the inorganic oxide is silica and the drying temperature is about 200 to 600°C.

19. The process of claim 17 wherein the inorganic oxide is magnesia and the drying temperature is about 200 to 600°C.

20. The process of claim 17 wherein the inorganic oxide is alumina and the drying temperature is about 500 to 600°C.

21. The process of claim 16 wherein the organometallic and vanadium compounds are added to the reaction mixture in neat form.

22. The process of claim 16 wherein at least one of the organometallic and vanadium compounds is added to the reaction mixture in the form of an inert liquid hydrocarbon solution.

23. A process which comprises polymerizing a monomer charge comprising ethylene in contact with the catalyst composition of claim 1.

24. The process of claim 23 wherein the polymerization is conducted under gas-phase polymerization conditions.

25. The process of claim 23 wherein the monomer charge con-sists essentially of ethylene.

26. The process of claim 23 wherein the monomer charge com-prises a mixture of ethylene and at least one alpha-olefin containing 3 to 12 carbon atoms.

27. The process of claim 26 wherein the monomer charge com-prises a mixture of ethylene and propylene.

28. The process of claim 26 wherein the monomer charge com-prises a mixture of ethylene and butene-1.