Support prepared from organomagnesium compounds and silicon halides; and catalysts for polymerizing olefins

A catalyst for the polymerization of olefins is prepared by the reaction of an aliphatic alcohol such as n-propyl alcohol with a mixture of an alkyl magnesium compound such as n-butyl, sec-butyl magnesium and a silicon tetrahalide such as SiCl.sub.4. After washing the precipitate several times with a hydrocarbon such as hexane, it is suspended in a hydrocarbon such as hexane and an organic titanium compound such as TiCl.sub.4 is added after which a suitable reducing agent such as diethyl aluminum chloride is added. The thus formed solid catalyst is washed several times with a hydrocarbon solvent such as hexane.

BACKGROUND OF THE INVENTION 
This invention relates to catalyst supports, catalysts, process for 
preparing such catalyst supports and catalysts and process for 
polymerizing olefins. 
It is well known that olefins such as ethylene, propylene, and 1-butene can 
be polymerized in the presence of metallic catalysts, particularly the 
reaction products of organometallic compounds and transition metal 
compounds to form substantially unbranched polymers of relatively high 
molecular weight. Typically such polymerizations are carried out at 
relatively low temperatures and pressures. The resulting generally linear 
olefin polymers are characterized by greater stiffness and higher density 
than olefin polymers having highly branched polymer chains. 
Among the methods for producing linear olefin polymers, some of the most 
widely utilized are those described by Professor Karl Ziegler in U.S. Pat. 
Nos. 3,113,115 and 3,257,332. In these methods, the catalyst employed is 
obtained by admixing a compound of a transition metal of Groups 4b, 5b, 6b 
and 8 of Mendeleev's Periodic Table of Elements with an organometallic 
compound. Generally the halides and oxyhalides of titanium, vanadium, and 
zirconium are the most widely used transition metal compounds. Outstanding 
examples of the organometallic compounds include hydrides, alkyls and 
haloalkyls of aluminum, alkyl aluminum halides, Grignard reagents, alkali 
metal aluminum hydrides, aklali metal borohydrides, alkali metal hydrides, 
alkaline earth metal hydrides and the like. 
Usually, polymerization is carried out in a reaction medium comprising an 
inert organic liquid, e.g., an aliphatic hydrocarbon, and the 
aforementioned catalyst. One or more olefins may be brought into contact 
with the reaction medium in any suitable manner, and a molecular weight 
regulator, which is normally hydrogen, is usually present in the reaction 
vessel in order to control the molecular weight of the polymers. 
Following polymerization, it is common to remove catalyst residue from the 
polymer by separating the polymer from the inert liquid diluent and then 
repeatedly treating the polymer with an alcohol or similar deactivating 
agent. Such catalyst deactivation and/or removal procedures are expensive 
both in time and material consumed as well as the equipment required to 
carry out such treatment. 
Furthermore, most of the aforementioned known catalyst systems are more 
efficient in preparing polyolefins in slurry (i.e., wherein the polymer is 
not dissolved in the carrier) than in solution (i.e., wherein the 
temperature is high enough to solubilize the polymer in the carrier). The 
lower efficiencies of such catalysts in solution polymerization is 
generally believed to be caused by the general tendency of such catalyst 
to become rapidly depleted or deactivated by significantly higher 
temperatures than are normally employed in solution processes. 
In view of the expense of removing catalyst residues from the polymer, it 
would be highly desirable to provide a polymerization catalyst which is 
sufficiently active, even at solution polymerization temperatures, to 
produce such high quantities of polymer per unit of catalyst that it is no 
longer necessary to remove catalyst residue in order to obtain polymer of 
the desired purity. 
SUMMARY OF THE INVENTION 
The present invention, in one aspect, is a catalyst support prepared by the 
reaction of an alcohol with a mixture of an organomagnesium compound and a 
silicon halide represented by the formula R'.sub.4-n SiX.sub.n. Said 
mixture is prepared in a non-polar solvent. The solid product is then 
washed several times with a liquid hydrocarbon so as to remove the soluble 
components. 
It is preferred to prepare the support by the controlled addition of the 
alcohol to the mixture of organomagnesium compound and silicon halide. 
Alternatively, the mixture of organomagnesium compound and silicon halide 
can be added to the aliphatic alcohol. The reaction is not temperature 
dependent within normal chemical reaction limits except as desired to 
control the particle size of the catalyst support. 
In another aspect of the present invention, a catalyst is prepared by 
adding to the above described support a transition metal compound of the 
Groups 4b, 5b, 6b, 7b or 8 of Mendeleev's Periodic Table of Elements, 
followed by the addition of a reducing agent under conditions which 
produces a catalytically active solid product. After completion of the 
reaction, the solid catalyst is washed several times with a liquid 
hydrocarbon to remove the unreacted quantities of the reactants and 
hydrocarbon soluble reaction products. Then, when desired, an aluminum 
alkyl co-catalyst is employed by either adding to the above prepared 
catalyst or by adding separately to the polymerization reactor. The 
magnesium:transition metal atomic ratio is from about 0.1:1 to about 30:1, 
preferably from about 0.2:1 to about 3:1 and the aluminum:transition metal 
atomic ratio is from about 5:1 to about 200:1 preferably from about 10:1 
to about 30:1. 
Still another aspect of the present invention is a process for polymerizing 
.alpha.-olefins in the presence of the previously mentioned catalyst under 
conditions characteristic of Ziegler polymerization. 
The catalyst of the present invention provides a means for reducing polymer 
buildup on the reactor walls, control of the polymer particle size by 
varying the temperature at which the support is formed and the temperature 
and rate at which the reducing agent is added, as well as limited control 
of the molecular weight distribution, low color in the polymer and a good 
bulk density when the polymer is produced by the slurry process. 
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
The present invention is most advantageously practiced in a polymerization 
process wherein an .alpha.-olefin is polymerized, generally in the 
presence of hydrogen as a molecular weight control agent, in a 
polymerization zone containing an inert diluent and the reaction product 
as hereinbefore described. The foregoing polymerization process is most 
beneficially carried out under inert atmosphere and relatively low 
temperature and pressure, although very high temperatures and pressures 
are optionally employed. 
Olefins which are suitably polymerized or copolymerized in the practice of 
this invention are generally the aliphatic .alpha.-monoolefins having from 
2 to 18 carbon atoms. Illustratively, such .alpha.-olefins can include 
ethylene, propylene, butene-1, pentene-1, 4-methylpentene-1, 
3-methylbutene-1, hexene-1, octene-1, dodecene-1, octadecene-1 and the 
like. It is understood that the .alpha.-olefins may be copolymerized with 
other .alpha.-olefins and/or with other ethylenically unsaturated monomers 
such as butadiene, isoprene, pentadiene-1,3, styrene, 
.alpha.-methylstyrene and similar ethylenically unsaturated monomers which 
do not destroy conventional Ziegler catalysts. Most benefits are realized 
in the polymerization of aliphatic .alpha.-monoolefins particularly 
ethylene and mixtures of ethylene and quantities which provide up to about 
20, especially from about 0.1 to about 10, weight percent of propylene, 
butene-1, hexene-1, octene-1 or similar higher .alpha.-olefin, or mixtures 
thereof, based on total monomer in the resultant polymer. 
The catalyst support employed herein is that solid product resulting from 
the reaction of an alcohol (R"OH) with a mixture of a hydrocarbon soluble 
organomagnesium compound (MgR.sub.2) and a silicon halide (R'.sub.4-n 
SiX.sub.n), in a non-polar solvent, wherein the molar ratio of 
ROH:MgR.sub.2 is at least 2:1 and the molar ratio of ROH:R'.sub.4-n 
SiX.sub.n is such that there is present at least one, preferably 2 to 3 X 
groups per OH group. 
As previously stated, if desired, the mixture of organomagnesium compound 
and silicon halide can be added to the aliphatic alcohol. 
Suitable non-polar solvents for the mixture of organomagnesium compound and 
silicon halide include aliphatic and aromatic hydrocarbons having from 
about 5 to about 10, preferably from about 6 to about 8 carbon atoms such 
as, for example, pentane, hexane, heptane, octane, nonane, decane, 
benzene, toluene, xylene, mixtures thereof and the like. The preferred 
hydrocarbon is that which is ultimately to be employed in the 
.alpha.-olefin polymerization reaction. 
The purpose of employing the mixture of organo magnesium compound and the 
silicon halide in a non-polar solvent is to prevent the usual reaction 
which occurs when such compounds are employed in polar solvents such as 
diethyl ether or tetrahydrofuran. 
The particular criteria for the ratios of reactants being that there should 
be present at least one equivalent of alcohol for each alkyl group 
contained in the organomagnesium compound. 
Suitable organomagnesium compounds are those represented by the formula 
MgR.sub.2 which are hydrocarbon soluble wherein each R is independently an 
aliphatic hydrocarbon group having from 1 to about 20 carbon atoms, 
preferably from about 2 to about 8 carbon atoms such as, for example, 
butyl isobutyl magnesium, butyl hexyl magnesium, dihexyl magnesium, 
dioctyl magnesium, butyl ethyl magnesium, butyl octyl magnesium, mixtures 
thereof and the like. 
Also included are organomagnesium compounds represented by the above 
formula, MgR.sub.2, which are hydrocarbon insoluble, but are readily 
rendered hydrocarbon soluble by the addition of small solubilizing 
quantities, e.g. from about 5% to about 50%, preferably from about 10% to 
about 20% by weight of an organo aluminum compound such as 
triisobutylaluminum, triethylaluminum or other alkyl aluminum compounds or 
other suitable solubilizing compound, such as an aluminum alkoxide, which 
does not poison Ziegler polymerization catalysts. 
Such organomagnesium compounds which are normally insoluble in hydrocarbons 
but which can be rendered soluble as above stated above include, for 
example, dibutyl magnesium, butyl ethyl magnesium, ethyl hexyl magnesium, 
dihexyl magnesium, butyl octyl magnesium, mixtures thereof and the like. 
The use of such compounds as mentioned above includes the solubilizing 
quantity of the organo aluminum compound. 
In some instances, it may be desirable to add small quantities of an organo 
aluminum compound, including aluminum alkoxides, even though the 
organomagnesium compound is sufficiently soluble so as to lower the 
viscosity. 
Suitable silicon halide compounds which can be employed herein include 
those compounds wherein R' is an alkyl group of from 1 to about 20 carbon 
atoms, preferably from 1 to about 6 carbon atoms and X is Cl, Br or I and 
n has a value of from 1 to 4 such as for example, SiCl.sub.4, SiBr.sub.4, 
CH.sub.3 SiCl.sub.3, (C.sub.2 H.sub.5).sub.2 SiCl.sub.2, (CH.sub.3).sub.3 
SiCl, mixtures thereof and the like. 
Suitable alcohols (R"OH) which can be employed herein include those having 
from 1 to about 20 carbon atoms, preferably from 1 to about 6 carbon 
atoms, such as, for example, methanol, ethanol, allyl alcohol, n-propanol, 
isopropanol, n-butanol, sec-butanol, tertbutanol, octadecanol, benzyl 
alcohol, mixtures thereof and the like. 
The temperature of the ROH and mixture of organo magnesium compound and 
silicon halide is usually maintained from about 0.degree. C. to about the 
boiling point of the hydrocarbon in which the organomagnesium compound and 
silicon halide is dissolved, preferably from about 100.degree. C. or less 
and more preferably from about 0.degree. C. to about 70.degree. C., to 
control the particle size of the support and subsequently the particle 
size of the polymer. 
If during the preparation of the support, the temperature employed is above 
40.degree. C., the temperature should be, immediately after completion of 
the reaction, lowered to at least about 25.degree. C. so as to prevent 
sintering (aggregation) of the particles. The reaction is essentially 
instantaneous with the addition of the alcohol which is added 
incrementally so as to aid in the control of the temperature since the 
reaction is exothermic. 
The thus prepared support is then washed with a liquid hydrocarbon so as to 
remove any of the unreacted reactants and soluble by-products. Suitable 
such hydrocarbons include for example, those having from about 6 to about 
8, carbon atoms, such as, for example, pentane, hexane, heptane, octane, 
nonane, decane, benzene, toluene, xylene, mixtures thereof and the like. 
The preferred hydrocarbon is that which is ultimately to be employed in 
the .alpha.-olefin polymerization reaction. 
The catalyst of this invention is prepared by adding to the above prepared 
support suspended in any of the aforementioned hydrocarbons, a transition 
metal compound followed by the addition, preferably in a controlled 
manner, of a suitable reducing agent under conditions which produces a 
catalytically active solid product. Such conditions suitably are at a 
temperature below the boiling point of the hydrocarbon diluent preferably 
below about 100.degree. C., most preferably below about 70.degree. C. When 
the catalyst is prepared at pressures above atmospheric, the low boiling 
diluents can be employed at temperatures above their atmospheric boiling 
point but the temperature should not exceed the boiling point of the 
diluent at the particular pressure employed. The hydrocarbon is removed by 
any suitable means such as decantation, filtration or the like and the 
solid catalyst is washed with hydrocarbon to remove any unreacted 
materials and/or reaction products. 
The atomic ratio of magnesium contained in the support to the transition 
metal employed is from about 0.1:1 to about 30:1, preferably from about 
0.2:1 to about 3:1. 
The above prepared catalyst can then be emploed either alone or in the 
presence of, as a co-catalyst, an organometallic compound which is a 
halide, hydride or totally alkylated derivative of the metals of Groups 
1a, 2a, 2b, 3a or 4a of the Periodic Table such as, for example, 
triisobutyl aluminum, triethyl aluminum, diethylaluminum chloride, 
ethylmagnesium bromide, diiso-butylaluminum hydride, mixtures thereof and 
the like, so as to provide a metal (Group 1a, 2a, 2b, 3a or 4a):transition 
metal atomic ratio of from about 1:1 to about 200:1 preferably from about 
10:1 to about 30:1. 
Exemplary transition metal compounds include, for example, the halides, 
such as the chlorides, bromides, and iodides of the transition metals of 
Groups 4b, 5b, 6b, 7b and 8 of Mendeleev's Periodic Table of Elements as 
set forth in Handbook of Chemistry and Physics, CRC, 48th Edition 
(1967-68). Exemplary metals include, for example, titanium, chromium, 
zirconium, vanadium, tungsten, manganese, molybdenum, ruthenium, rhodium, 
cobalt, and nickel with titanium, vanadium and zirconium either separately 
or in combination being preferred. Exemplary preferred transition metal 
compounds are titanium tetrachloride, titanium trichloride, zirconium 
tetrachloride, vanadium tetrachloride, vanadium pentachloride, vanadium 
oxydichloride with the halides, particularly the chlorides, of titanium 
being most preferred. 
Exemplary reducing agents are those of conventional Ziegler catalysts 
including metals such as aluminum, sodium and lithium; hydrides thereof 
such as lithium aluminum hydride, or sodium borohydride; Grignard reagents 
such as phenylmagnesium bromide; and preferably organometallic compounds, 
especially alkyl aluminum compounds, mixtures thereof and the like. For 
the purposes of illustration, the alkyl aluminum compounds can be 
represented by the general formula RAlYY' wherein R is alkyl, most 
advantageously containing from 1 to 12 carbon atoms, or hydrogen; each Y 
and Y' is selected from the group consisting of alkyl or alkoxy 
groupshaving from 1 to 12 carbon atoms, hydrogen, and halogen, e.g., 
chlorine or bromine. 
The reducing agent or mixture of reducing agents can be added as pure 
compounds or they may be added as a mixture in an inert medium, 
particularly those inert mediums employed in preparing the support. 
In the preparation of the catalyst of the present invention, it is 
preferred to add the reducing agent in a controlled manner, i.e. 
incrementally rather than all at once. 
Examples of especially preferred compounds corresponding to the formula 
RAlYY', include trimethylaluminum, triethylaluminum, triisobutylaluminum, 
tri-n-butylaluminum, tri-n-pentylaluminum, triisooctylaluminum, 
tri-n-decylaluminum, tri-n-dodecylaluminum, diethylaluminum chloride, 
diethylaluminum hydride, mixtures thereof and the like. Especially 
preferred are triethylaluminum, triisobutylaluminum and diethylaluminum 
chloride. Other organometallic compounds which are likewise suitable 
include butyllithium, amylsodium, phenylsodium, dimethylmagnesium, 
diethylmagnesium, diethylzinc, butylmagnesium chloride and phenylmagnesium 
bromide. 
In the preparation of the catalyst composition, it is preferred to carry 
out such preparation in the presence of an inert diluent. By way of an 
example of suitable inert organic diluents can be mentioned liquified 
ethane, propane, isobutane, n-butane, n-hexane, the various isomeric 
hexanes, isooctane, isononane, paraffinic mixtures of alkanes having from 
8 to 9 carbon atoms, cyclohexane, methylcyclopentane, dimethylcyclohexane, 
dodecane, industrial solvents composed of saturated or aromatic 
hydrocarbons such as kerosene, naphthas, and mixtures of any two or more 
of the foregoing, especially when freed of impurities which 
characteristically poison Ziegler catalysts, and especially those having 
boiling points in the range from about -50.degree. C. to about 200.degree. 
C. Also included as suitable inert diluents are benzene, toluene, 
ethylbenzene, cumene, decalin and the like. 
Mixing of the catalyst components to provide the desired catalyst 
composition is advantageously carried out under an inert atmosphere such 
as nitrogen, argon or other inert gas. 
In the polymerization process employing the aforementioned catalyst 
composition, polymerization is effected by adding a catalytic amount of 
the catalyst composition to a polymerization zone containing 
.alpha.-olefin monomer, or vice versa. The polymerization zone is 
maintained at temperatures in the range of from about 0.degree. to about 
300.degree. C., preferably at slurry polymerization temperatures (e.g., 
from about 30.degree. to about 90.degree. C.), for a residence time of 
about 10 minutes to several hours, preferably from 15 minutes to 5 hours. 
It is generally desirable to carry out the polymerization in the absence 
of moisture and oxygen. A catalytic amount of the catalyst composition is 
advantageously within the range of from about 0.0001 to about 1 
milligram-atom of transition metal per liter of diluent. It is understood, 
however, that the most advantageous catalyst concentration depends upon 
polymerization conditions such as temperature, pressure, solvent and 
presence of catalyst poisons. It is further understood that the foregoing 
range is given to obtain maximum catalyst yields. In the polymerization 
process, a carrier which may be an inert organic diluent or solvent or 
excess monomer is generally employed. In order to realize the full benefit 
of the high efficiency catalyst of the present invention care must be 
taken to void oversaturation of the solvent with polymer. If such 
oversaturation occurs before the catalyst becomes depleted, the full 
efficiency of the catalyst is not realized. For best results, it is 
preferred that the amount of polymer in the carrier not exceed about 50 
weight percent based on the total weight of the reaction mixture. Inert 
diluents employed in the polymerization recipe are suitable as defined as 
hereinbefore. 
The polymerization pressures usually employed are relatively low, e.g., 
from about 40 to about 500 psig. However, polymerization within the scope 
of the present invention can occur at pressures from atmospheric up to 
pressure determined by the capabilities of the polymerization equipment. 
During polymerization it is very desirable to stir the polymerization 
recipe to obtain better temperature control, to maintain uniform 
polymerization mixtures throughout the polymerization zone, and to insure 
contact between the olefin and the catalyst. 
Hydrogen is often employed in the practice of this invention to control 
molecular weight of the resultant polymer. For the purpose of this 
invention, it is beneficial to employ hydrogen, when employed, in 
concentrations ranging from about 0.001 to about 1 mole per mole of 
monomer. The larger amounts of hydrogen within this range are found to 
produce generally lower molecular weight polymers. It is understood that 
hydrogen can be added with a monomer stream to the polymerization vessel 
or separately added to the vessel before, during or after addition of the 
monomer to the polymerization vessel, but during or before the addition of 
the catalyst. 
The monomer or mixture of monomers is contacted with the catalyst 
composition in any conventional manner, preferably by bringing the 
catalyst composition and monomer together with intimate agitation provided 
by suitable stirring or other means. In the case of more rapid reactions 
with more active catalysts, means can be provided for refluxing monomer 
and solvent, if any of the latter is present, and thus remove the heat of 
reaction. In any event, adequate means should be provided for dissipating 
the exothermic heat of polymerization. If desired, the monomer can be 
brought in the vapor phase into contact with the catalyst composition, in 
the presence or absence of liquid material. The polymerization can be 
effected in the batch manner, or in a continuous manner, such as, for 
example, by passing the reaction mixture through an elongated reaction 
tube which is contacted externally with suitable cooling medium to 
maintain the desired reaction temperature, or by passing the reaction 
mixture through an equilibrium overflow reactor or a series of the same. 
The polymer is readily recovered from the polymerization mixture by driving 
off unreacted monomer and solvent if any is employed. Thus, a significant 
advantage of the present invention is reduction of the catalyst residues 
remaining in the polymer. Often, the resultant polymer is found to contain 
insignificant amounts of catalyst residue such that catalyst removal 
procedures can be entirely eliminated. 
The following examples are given to illustrate the invention, and should 
not be construed as limiting its scope. All parts and percentages are by 
weight unless otherwise indicated. 
In the following examples, the melt index values, I.sub.2, were determined 
by ASTM D 1238, condition E. The apparent bulk density was determined as 
an unsettled bulk density according to the procedure of ASTM 1895 
employing a paint volumeter from the Sargent-Welch Scientific Company 
(Catalog no. S-64985) as the cylinder instead of the one specified by the 
ASTM procedure.

GENERAL PROCEDURE 
In each of the following examples, the catalyst components were blended 
while in a gloved box filled with nitrogen unless otherwise indicated. 
EXAMPLE 1 
A. Preparation of Catalyst Support 
To a beaker was added 0.03 mole of a 0.5 molar solution of dihexyl 
magnesium in hexane. To this was added 0.03 mole of silicon tetrachloride 
in a single portion and the total volume of the mixture was adjusted to 
400 cc with additional dry hexane. As the mixture was stirred at 
25.degree. C. a second solution was added dropwise. This solution 
consisted of 0.06 mole of normal propyl alcohol dissolved in 50 cc of 
hexane. No temperature control was maintained. Upon finishing the addition 
the reaction mixture was stirred for an additional 10 minutes and then the 
stirring was stopped which allowed the newly formed precipitate to settle. 
The hexane was decanted and the solid was washed five times with dry 
hexane and then suspended in 300 cc of hexane with agitation. 
B. Preparation of Catalyst 
1. To the support prepared in A above was added 0.15 mole of TiCl.sub.4 in 
a single portion followed by a dropwise addition of 0.3 mole of diethyl 
aluminum chloride (as a 25% solution in hexane). The temperature was 
maintained below 40.degree. C. during the addition. The resultant brown 
solid was then allowed to settle and the hexane was decanted. The solid 
was washed 5 times with dry hexane and suspended in 200 cc of hexane. The 
Mg:Ti atomic ratio was 0.33:1. 
2. To a support prepared as in A above was added 0.01 mole of TiCl.sub.4 in 
a single portion. To this was added dropwise 0.02 mole of diethyl aluminum 
chloride (25% solution in hexane). The temperature was maintained below 
40.degree. C. throughout the addition. The solid was washed 5 times in dry 
hexane and suspended in 200 cc of hexane. The Mg:Ti atomic ratio was 3:1. 
C. Polymerization of Ethylene 
1. A one liter, batch reactor fitted with a mechanical stirrer, gas inlet 
tubes and controlled temperature jacket was filled with 500 cc of dry 
hexane. Under a nitrogen atmosphere was added 0.6 millimole of triisobutyl 
aluminum and 0.02 millimole (based on the Ti concentration) of the brown 
solid catalyst prepared in 2-A. The Al:Ti atomic ratio was 30:1. This 
mixture was then sealed and purged with hydrogen. The temperature was set 
at 80.degree. C. and 50 psi hydrogen was introduced. With stirring a 
constant 170 psi ethylene was added and maintained throughout the 90 
minute reaction time. The resultant polyethylene weighed 98 gm. (102,000 g 
polymer/g Ti), and had a melt index of 0.11 gm/10 min with a 200 gm 
weight. 
2. In like manner as in C-1 ethylene was polymerized employing the catalyst 
prepared in B-2. The concentration of catalyst was again 0.02 millimole 
(based on Ti concentration) and 0.6 millimole of triisobutyl aluminum was 
also used. The Al:Ti atomic ratio was 30:1. The resultant polymer weighed 
270 gm (281,000 g polymer/g Ti) and had a 0.28 melt index as measured in 
example C-1. 
EXAMPLE 2 
A catalyst prepared as in example 1-B-2 was employed to polymerize ethylene 
in the same manner as in Example 1-C-1 except that the amount of 
co-catalyst (triisobutylaluminum) was changed and the effect noted. 
(A) 0.02 millimole of catalyst 1-B-2 was employed with 0.2 millimole of 
triisobutylaluminum. The Al:Ti atomic ratio was 10:1. The resultant 
polymer weighed 161 gm (168,000 g polymer/g Ti) and had a melt index of 
0.13. 
(B) 0.01 millimole of catalyst 1-B-2 was employed with 1.0 millimole of 
triisobutylaluminum. The Al:Ti atomic ratio was 100:1. The resultant 
polymer weighed 308 grams (643,000 g polymer/g Ti) and had a melt index of 
0.32. 
EXAMPLE 3 
A support was prepared in the same manner as in example 1-A employing 0.02 
mole of dibutyl magnesium and 0.02 mole of silicon tetrachloride. The 0.04 
mole of isopropyl alcohol was added dropwise forming a white precipitate 
which was decanted and washed 5 times with dry hexane and then suspended 
in 250 cc of hexane with mechanical agitation. 
To this was added 0.01 mole of TiCl.sub.4 followed by the dropwise addition 
of 0.02 mole of diethyl aluminum chloride. The resultant brown solid 
catalyst was washed several times with hexane. The Mg:Ti atomic ratio was 
2:1. 
To the same reactor system as employed in example 1-C-1 was added 0.05 
millimole (based on Ti concentration) of this catalyst and 2 millimole of 
triisobutylaluminum. The Al:Ti atomic ratio 40:1. The resultant 
polyethylene weighed 226 grams (94,400 g polymer/g Ti) and had a 0.4 melt 
index. 
EXAMPLE 4 
(A) To a beaker was added 0.05 mole of a 0.5 molar solution of dibutyl 
magnesium in hexane. To this was added 0.05 mole of silicon tetrachloride 
in a single portion and the total volume of mixture was adjusted to 500 cc 
with hexane. The stirring was begun and this solution was heated to 
45.degree. C. Next, 0.10 mole of normal propyl alcohol was added dropwise 
over a 30 minute period. As soon as the exothermic addition was complete, 
the temperature was rapidly lowered to 25.degree. C. The solid was 
decanted and washed five times with hexane. Next, 0.15 mole of TiCl.sub.4 
was added and stirred with the solid in 350 cc of hexane. To this was 
added 0.30 mole of diethyl aluminum chloride while maintaining a 
temperature below 40.degree. C. The resulting brown solid catalyst was 
decanted and washed five times with hexane. The Mg:Ti atomic ratio was 
0.33:1. 
This material was used in the same reactor and under the same conditions as 
given in Example 1-A, 0.02 millimole of catalyst (based on Ti 
concentration) was used in conjunction with 0.6 millimole of 
triisobutylaluminum. The resultant polymer weighed 134 grams (140,000 g 
polymer/g Ti) and had a 0.3 melt index. 50% of the polymer was retained by 
a 100 mesh screen. 
(B) The procedure above was followed except that the normal propyl alcohol 
addition was made at 60.degree. C. instead of 45.degree. C. The resultant 
polymer weighed 141 grams (147,000 g polymer/g Ti), had a melt index of 
0.35 and 30% was retained by a 100 mesh screen. 
The above example demonstrated the effect that temperature control during 
the preparation of the catalyst support has on the particle size of 
polymers prepared from catalysts supported thereon. 
EXAMPLE 5 
To a beaker was added 0.025 mole of dihexyl magnesium in hexane. To this 
was added 0.025 mole of silicon tetrachloride and the volume adjusted to 
400 cc of hexane. Normal propyl alcohol (0.05 mole) was diluted with 50 cc 
of hexane and added dropwise with stirring. The starting temperature of 
the addition was 25.degree. C. The resulting white solid support was 
decanted and washed five times with hexane. 
To a slurry of the above prepared white solid support in 300 cc of hexane 
was added 0.025 mole of TiCl.sub.4 with stirring. Next was added 0.05 mole 
of triisobutylaluminum from an 18% by weight solution in hexane. The 
temperature was maintained below 35.degree. C. during the addition. The 
resultant solid catalyst was decanted and washed 5 times with hexane. The 
Mg:Ti atomic ratio was 1:1. 
The same reactor and conditions were employed as in example 1-C with the 
following catalyst amounts, 0.01 millimole of the above prepared catalyst 
(based on Ti concentration) and 0.3 millimole of triisobutylaluminum were 
added to the reactor. The Al:Ti atomic ratio was 30:1. The resultant 
polymer weighed 149 gm (311,000 g polymer/g Ti) and had a melt index of 
0.07. 
EXAMPLE 6 
A. Preparation of Catalyst 
To a beaker was added 0.056 mole of di-n, sec-butyl magnesium in hexane. To 
this was added 0.056 mole of silicon tetrachloride and the volume adjusted 
to 400 cc of hexane. Normal propyl alcohol (0.112 mole) was diluted with 
50 cc of hexane and added dropwise with stirring. The starting temperature 
of the addition was 10.degree. C. During the addition the temperature was 
controlled such that the maximum temperature was 12.degree. C. and the 
final temperature was 8.degree. C. The resulting white solid was decanted 
and washed five times with hexane. 
To a slurry of the white solid in 250 cc of hexane was added 0.112 mole of 
TiCl.sub.4 with stirring. Next was added 0.123 mole of triisobutylaluminum 
from an 18% by weight solution in hexane. The temperature was maintained 
at 30.degree. C. during the addition. The resultant solid catalyst was 
decanted and washed 5 times with hexane. The Mg:Ti atomic ratio was 0.5:1. 
B. Polymerization of Ethylene 
The same reactor and conditions were employed as in example 1-C with the 
following catalyst amounts, 0.04 millimole of the above prepared catalyst 
(based on Ti concentration) and 4.0 millimoles of triisobutylaluminum were 
added to the reactor. The Al:Ti atomic ratio was 100:1. After a 2 hour 
reaction time, the resultant polymer weighed 133 gm (69,400 g polymer/g 
Ti) and had a melt index of 0.60. 
EXAMPLE 7 
A. Preparation of Catalyst 
To a beaker was added 0.120 mole of propyl alcohol dissolved in 200 cc of 
hexane. A second mixture, comprised of 0.059 mole of butyl-sec-butyl 
magnesium and 0.059 mole of silicon tetrachloride in 100 cc of hexane, was 
added to the alcohol solution while it stirred at 30.degree. C. The 
addition time was approximately 20 minutes. After the exothermic reaction 
subsided, the resultant white solid was washed several times with fresh 
hexane. This solid was suspended in 350 cc of hexane and 0.072 mole of 
titanium tetrachloride was added in a single portion with stirring. To 
this was added 0.088 mole of diethyl aluminum chloride while maintaining 
the temperature below 40.degree. C. The resultant brown solid was decanted 
and washed 5 times with dry hexane. 
B. Polymerization of Ethylene 
This material was used in the same reactor and conditions as described in 
Example 1-C. The partial pressure of hydrogen was 30 psi instead of 50 
psi, but the remainder of the values were those given in Example 1-C. The 
catalyst, 0.015 millimole, was placed in the reactor with 0.750 millimole 
of trisobutylaluminum. The Al:Ti atomic ratio was 50:1. The resultant 
polymer weighed 185 gm (257,000 g polymer/g Ti) and had a melt index of 
0.10. 
EXAMPLE 8 
A. Preparation of Catalyst 
A solution of n-propylalcohol (7.6 ml, 101 millimoles) in hexane (200 ml) 
was added dropwise to a stirred solution of 5.7 ml silicon tetrachloride 
(50 millimoles) and 78 ml 0.637 molar butylethyl magnesium (50 millimoles) 
in heptane. The solids were allowed to settle and about 140 ml of the 
supernatant liquid was removed by decantation. Isopar.RTM. E, an 
isoparaffinic hydrocarbon fraction with a boiling point range of 
116.degree.-134.degree. C., was added to give a total volume of 200 ml. 
The decanation procedure was repeated two more times. The Isopar.RTM. E 
slurry was mixed with 11.0 ml of titanium tetrachloride (100 millimoles) 
and heated to 90.degree. C. A solution (68 ml) of 1.46 molar 
diethylaluminum chloride (100 millimoles) was added dropwise in 30 minutes 
to the stirred slurry. The slurry was maintained at a temperature of 
90.degree. to 100.degree. C. for another 30 minutes and then cooled to 
room temperature. The hydrocarbon insoluble products were allowed to 
settle and the supernatant liquid was removed by decantation. The solids 
were reslurried with fresh hexane and the decantation procedure was 
repeated five more times to remove the hexane soluble reaction products. 
B. Polymerization of Ethylene 
Triisobutylaluminum (1.00 millimole) and an aliquot of catalyst containing 
0.02 millimole of titanium were added to a stirred 1.8 liter reactor 
containing 1.0 liter of dry, oxygen-free hexane. The nitrogen atmosphere 
in the reactor was replaced with hydrogen, the reactor contents were 
heated to 85.degree. C., and the reactor pressure was adjusted to 70 psig 
with hydrogen. Ethylene was then added to maintain a reactor pressure of 
170 psig. After two hours the reactor contents were filtered and the 
polyethylene dried in a vacuum overnight at about 60.degree. C. The 
resultant polymer weighed 144 gm (150,000 g polymer/g Ti), had a bulk 
density of 14.2 pounds per cubic foot and had a melt index of 0.31.