Alumoxane-enhanced, supported ziegler-natta polymerization catalysts, methods of making same, processes of using same and polymers produced therefrom

The present invention relates to a new olefin polymerization catalyst composition, and methods of preparing and methods of using the catalysts to polymerize various olefinic monomers in either gas or slurry phase reactions. The principal advance over the previous art of record involves using alumoxanes or combinations of alumoxanes as catalyst preactivators. Polymers prepared from these catalysts posses productivity increased as high as 40 percent. At the same time, the bulk density remains relatively constant. Additionally, the total amount of cocatalyst species needed to effectively practice the invention is relatively low.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The invention relates to supported modified Ziegler-Natta type 
transition-metal based catalysts, methods for making the same, methods of 
using the same and polymeric products obtained therefrom. 
2. Description of the Related Art 
Several publications are referenced in this application. These references 
describe the state of the art to which this invention pertains, and are 
incorporated herein by reference. 
The field of olefin catalysis has witnessed many remarkable discoveries 
during the last 50 years. In particular, two broad areas of invention 
having exceptional industrial importance stand out. First, in the 1950's 
the Ziegler-type catalysts were discovered and exploited in a variety of 
applications. Even today, these catalyst systems are used in many 
commercially important operations. Secondly, and more recently, the 
discovery of the "Metallocene"-type transition metal catalysts which are 
prepared with various cyclopentadiene and substituted cyclopentadiene 
derivatives have provided another important advance in polyolefin research 
and commercial products. 
However, both of these important discoveries have certain limitations as 
known to those of ordinary skill in the art. Traditional Ziegler-Natta 
(hereafter referred to as Z-N) catalysts suffer from limited productivity, 
meaning the efficiency of conversion from monomer to polymer per unit of 
catalyst consumed is low. One method which has been attempted to enhance 
the productivity of traditional Z-N catalysts involves the pre-treatment 
or pre-activation of certain transition metal catalyst compositions using 
conventional aluminum alkyls. 
In contrast, the metallocene-type catalysts possess extremely high rates of 
productivity. However, many commercial plants are not able to use such 
high levels of productivity and refitting such plants would be 
prohibitively expensive. Often, the amount of polymer produced is in 
excess of the down stream equipment's ability to process the product. 
Finally, large amounts of expensive alumoxane cocatalysts are required to 
initiate and sustain metallocene-based polymerizations. Consequently, 
these types of catalyst systems are sometimes modified by the addition of 
traditional Z-N catalysts (non-metallocene-type catalysts) to reduce the 
rates of productivity and thereby modify the properties of polymers 
produced to yield useful commercial products. These modifications are 
suggested to improve the molecular weight distributions and physical 
properties of polymers produced using these catalysts. 
Thus, there appears to be an unmet, unfilled need in the field of olefin 
transition metal catalyst polymerization wherein the productivity or 
efficiency of the catalysts could be economically improved without 
compromising the useful characteristics of the resultant materials. More 
specifically, the improvements in productivity would mean that less 
catalyst is consumed thus resulting in significant economic savings in 
costs associated with producing a given quantity of polymer. 
U.S. Pat. Nos. 4,701,432 and 5,183,867 to Welborn, Jr., et al., relate to 
supported olefin polymerization catalysts and processes of using same. 
These catalysts may contain at least one metallocene of a metal of Group 
IVB, VB, and VIB of the Periodic table, a non-metallocene transition 
metal-containing compound of a Group IVB, VB, or VIB metal and an 
alumoxane, the catalytic product being formed in the presence of the 
support. The catalyst is useful for the polymerization of olefins, 
especially ethylene and especially for the copolymerization of ethylene 
and other mono and diolefins. More specifically, the patents describe 
supported olefin catalyst systems wherein the catalyst components consist 
of a metallocene, a nonmetallocene transition metal component, an 
alumoxane and optionally, a cocatalyst system of an organic compound of a 
metal of Groups I-III of the Periodic Table, known to those skilled in the 
art as aluminum alkyls. 
U.S. Pat. No. 5,183,867 to Welborn also relates to a two component 
transition metal complex for preparing polymers having multimodal 
molecular weight distributions (MWD). 
U.S. Pat. No. 4,303,771 to Wagner et al. relates to a catalytic process for 
preparing ethylene polymers having a density between about 0.94 and 0.97 
and a melt flow ratio of between about 22 and 32. The polymers are 
prepared in a low pressure reactor at a productivity of greater than or 
equal to 50,000 lbs of polymer per pound of Ti. The process uses a 
catalyst formed from selected organoaluminum compounds and a precursor 
composition being the reaction product of TiCl.sub.3, MgCl.sub.2, and THF 
as an electron donor (ED) compound in specific ratios. The aluminum alkyl 
is used as a "partially activating" agent before the catalyst is 
introduced into the reactor. 
U.S. Pat. No. 4,302,566 to Karol et al. relates to the preparation of 
transition metal catalysts diluted with an inert carrier material and 
formed with selected organo aluminum compounds. Additionally, the Karol 
patent teaches specific activation sequences for the catalytic entities. 
U.S. Pat. No. 4,124,532 to Giannini et al. describes the usefulness of 
incorporating various alkali and alkali earth metal complexes, e.g. 
MgCl.sub.2, into olefinic transition metal polymerization catalysts. These 
complexes are taught as having a positive effect on the activity of the 
polymerization of ethylene and alpha-olefins while being generally much 
less active than the corresponding transition metal halides. 
It would be advantageous to provide a catalyst for olefin polymerizations 
having a useful range of productivity which is greater than that of a 
typical Z-N catalyst while less than that of many metallocene systems. It 
would be further useful to, at the same time, improve various physical 
properties of the polymers produced, e.g. molecular weight distributions 
and bulk density. Still another advantage would be improved flexibility in 
choosing the combinations of co-catalyst systems useful to preactivate and 
then activate the catalyst systems, while maintaining or improving the 
productivity and physical properties of the resultant polymers and 
copolymers. 
None of the above-identified patents teach or suggest the beneficial 
effects of deliberate sequences of pre-activation and subsequent full 
activation of the catalysts using either alumoxanes alone or in 
conjunction with traditional aluminum alkyl type transition metal 
polymerization activators. 
OBJECTS OF THE INVENTION 
It is an object of the invention to overcome the above-identified 
deficiencies. 
It is another object of the invention to provide a catalyst for use in 
olefin polymerizations having a useful, improved range of productivity. 
It is a further object of the invention to provide a method of making 
improved catalysts for use in olefin polymerizations. 
It is a still further object of the invention to provide methods of making 
improved polymer products from olefin polymerizations having improved 
physical properties including improved molecular weight distributions 
and/or bulk density, and methods of making the same. 
The foregoing and other objects and advantages of the invention will be set 
forth in or apparent from the following description. 
SUMMARY OF THE INVENTION 
The invention relates to improved supported modified Ziegler-Natta type 
transition-metal based catalysts, methods for making the same, methods of 
using the same and polymeric products obtained therefrom. The inventors 
have discovered, unexpectedly and surprisingly, novel catalyst systems and 
processes for the polymerization of olefinic monomers, particularly 
ethylene, and copolymers with various comonomers such as propylene, 
1-butene, 1-pentene, 1-hexene, 1-octene, 4-methyl pentene and the like. 
The novel catalysts have an improved catalytic productivity over many 
conventional Z-N catalyst systems while meeting the other required 
characteristics of such catalysts. The activity, depending on the specific 
embodiment of the invention, may be increased by a factor of 40 percent 
over typical conventional Ziegler-Natta catalysts. 
The inventors have discovered, unexpectedly and surprisingly, that when 
certain combinations of TiCl.sub.3, MgCl.sub.2, and THF are reacted and 
then pre-activated for polymerization with alumoxanes alone or with 
various aluminum alkyls, and subsequently activated with various other 
aluminum alkyls, either alone or in combination, the resultant catalysts 
have further enhanced polymerization productivity. 
The polymerizations according to the invention may be conducted in slurry 
or gas phase, as known to those skilled in the art, and may be conducted 
over a temperature range of 30 to 110.degree. C. The polymers produced 
using various embodiments of the present invention possess a broad range 
of molecular weights and distributions, while the process of making the 
polymers provides for increased productivity. Additionally, the polymers 
maintain relatively constant bulk properties, e.g. bulk density. 
Moreover, the catalyst systems of the invention reduce the quantity of 
expensive alumoxanes that are required in metallocene systems. 
DESCRIPTION OF THE PREFERRED EMBODIMENTS 
The supported transition metal based catalyst systems of the present 
invention are preferably obtained by preparing a precursor containing the 
reaction product of at least one transition metal compound, at least one 
alkali earth halide or alkali metal halide complex and an electron donor, 
and supporting the precursor on an appropriate support and pre-activating 
the precursor with an aluminoxane or mixtures of aluminoxane and aluminum 
alkyl. 
The precursor contains the reaction product of at least one transition 
metal compound, one alkali earth halide or alkali metal halide and at 
least one electron donor (ED) preferably selected from ethers or esters 
groups. 
The precursor can be a solution or supported on appropriate support (e.g., 
silica). The catalyst is produced by treating the supported precursor with 
methylalumoxane (MAO) prior to injecting the precursor into the reactor 
vessel. Preferably, TEAL is used as a co-catalyst and is added to the 
reactor prior to injection of the catalyst. It is believed this order of 
operation produces the best recipe for ethylene polymerization. 
Support materials include silica, alumina, silica--alumina compound and 
mixtures thereof, as known by those skilled in the art. The catalysts of 
the present invention are typically supported with silica supports 
(preferably pre-treated silica which has been dehydrated and treated with 
TEAL), either surface modified or not in a manner known to those of 
ordinary skill in the art of olefin polymerization catalysis. 
Additionally, other suitable support materials may be employed, for 
example, finely divided polyethylene or polystyrene. The silica support is 
substantially dehydrated to minimize the surface hydroxyl group density 
making the support inert towards the catalyst precursor. Such treatments 
may be carried out in vacuum or while fluidizing with an inert gas such as 
nitrogen or argon and the like at a temperature between about 200 to 
1000.degree. C., preferably, from 400.degree. C. to 600.degree. C. Such 
thermal treatment may be for any sufficient length of time but preferably 
anywhere from 2 to 20 hours. The silica may be chosen as necessary, 
however, a particularly useful but non-limiting size range is from 1 to 
500 microns in diameter. 
A ratio of 2 to 10 weight percent of the support material can be used. 
Support pre-treatment may be carried out at a temperature from 30.degree. 
C. to the boiling point of the solvent, preferably 40.degree. C. to 
60.degree. C., for 2 to 8 hours. A suitable low boiling point hydrocarbon 
diluent such as hexane, heptane or isopentane and the like may be useful 
as a slurry medium to accomplish such treatment. 
To promote the catalyst productivity, the support material may be suitably 
modified with organomagnesium and/or organoaluminum compounds such as 
conventional alkyl aluminums or alkyl magnesium and the like. 
The inventive catalyst systems contain at least one transition metal. 
Illustrative, but non-limiting, examples of useful transition metal 
precursor compounds include TiCl.sub.3, TiCl.sub.4, Ti(OC.sub.2 
H.sub.5).sub.3 Cl, VOCl.sub.3, VCl.sub.4, ZrCl.sub.4, ZrCl.sub.3 (OC.sub.2 
H.sub.5) and the like. 
The inventive catalyst systems also contain at least one alkali metal 
compound. Examples of the alkali metal compounds include CaBr.sub.2, 
CaCl.sub.2, MgCl.sub.2 and MgBr.sub.2. MgCl.sub.2 is the preferred 
compound and anhydrous MgCl.sub.2 the most preferred. Approximately, 1 to 
10 mols of magnesium chloride per mol of the titanium compounds may be 
used and is preferred. 
The inventive catalyst systems also comprise at least one electron donor 
compound. Illustrative but non-limiting examples of electron donor 
compounds include aliphatic and aromatic esters, aliphatic ethers, cyclic 
ethers, and aliphatic ketones. The preferred electron donors include 
tetrahydrofuran, dioxane, acetone, methyl formate and ethyl ether. The 
most preferred electron donor compound is tetrahydrofuran. The electron 
donor compound may be preferably from 2 to 20, and more preferably from 
about 5 to 15 mols of electron donor per mole of Ti containing compound. 
The supported Catalyst precursors are pre-activated with an activator, 
e.g., alumoxanes, at an activator to Ti molar ratio of up to about 100 to 
1, more preferably, about 10 to 1 an most preferably 3 to 1 aluminum to 
titanium molar ratio. Pre-activation is achieved using a hydrocarbon 
slurry medium typically at about 15-30.degree. C. with continuous mixing 
followed by drying at temperatures between about 40.degree. C. to 
100.degree. C., and preferably 50.degree. C. to 80.degree. C. to obtain a 
free-flowing solid. Illustrative but non-limiting examples of the 
preactivators employed in the present invention include but are not 
limited to polymeric methyl aluminoxane (MAO), diethyl aluminum chloride, 
tri n-hexyl aluminum, tri ethyl aluminum and mixtures thereof. 
The preactivated catalyst precursor is fed into a suitable reactor under a 
nitrogen atmosphere, typically in a slurry with an inert hydrocarbon 
diluent such as hexane, heptane, isopentane, toluene or mineral oil or 
other HC as known in the art. The cocatalyst (e.g., TEAL) is diluted from 
about 2 to 40 wt % in a similar hydrocarbon solvent as used to slurry the 
preactivated catalyst, and subsequently added to the reactor as a 
solution. The TEAL enhances the alkylation step, alkylates titanium to 
produce carbon-metal bonds (active sites). Other organoaluminum compounds 
may also be used as a cocatalyst added to the reactor before the alumoxane 
pre-treated catalyst. Suitable organoaluminum compounds include triethyl 
aluminum, diethyl aluminum chloride, trisobutyl aluminum, methyl alumoxane 
and mixtures thereof. The Al/Ti molar ratio of the system is preferably 
from 25 to 100, and more/preferably 35 to 75 depending on the specific 
embodiment. The-most preferred range is about 45 to 60. The polymerization 
reaction is carried out by introducing monomer and hydrogen into the 
reactor. Preferably, the reaction temperature is between 50.degree. C. to 
120.degree. C., more preferably 70.degree. C. to 100.degree. C. and most 
preferably 80-90.degree. C. The total reactor pressure is from 5 to 30 
bar, preferably 7 to 20 bar. Using the invention, the typical catalyst 
productivity can be 170,000 grams or more of polymer per gram of 
Ti-containing catalyst. 
The typical molecular weight of polyethylene homopolymers obtained in 
accordance with the present invention vary over a wide range, preferably 
ranging from 1,000 to 700,000. The polydispersity index (molecular weight 
distribution) expressed as Mw/Mn can vary from 2.5 to 8. The molecular 
weight and molecular weight distributions are additionally dependent on 
the hydrogen concentration, catalyst systems and polymerization 
temperature used as known to those skilled in the art. 
The produced polymer density may vary from about 0.90 to 0.97 gm/cc, 
depending on the particular embodiment of catalyst and monomer reaction 
conditions used, or comonomer used. The polymers produced using the 
catalyst of the present invention have a bulk density of about 0.30 to 
0.43 g/cc and preferably about 0.35 to 0.39 g/cc (as measured by an ASTM 
test), depending on the particular embodiment.

EXAMPLES 
The following examples are illustrative of some of the products and methods 
of making the same falling within the scope of the present invention. They 
are, of course, not to be considered in any way limitative of the 
invention. Numerous changes and modifications can be made with respect to 
the invention. 
Catalyst Precursor Preparation 
In a round bottom flask, 44 grams of porous silica were dehydrated in a 
flow of dry nitrogen (N.sub.2) at 600.degree. C. After cooling, the silica 
was slurried with 120 ml hexane at room temperature for 30 minutes under 
N.sub.2 atmosphere using a magnetic stirrer. An amount of 22 ml of 
triethylaluminum (TEAL) was added and mixed with the slurry for 30 minutes 
at room temperature, then dried at about 70.degree. C. A dry free-flowing 
solid of the silica containing 5.7% TEAL was obtained (Chemical A). 
In a round bottom flask, 1 g of titanium trichloride (TiCl.sub.3.1/3 
AlCl.sub.3) and 1.14 g of anhydrous magnesium chloride (MgCl.sub.2) were 
dissolved in 120 ml of freshly distilled tetrahydrofuran (THF) under 
continuous refluxing using a magnetic stirrer. The mixture was stirred at 
a temperature of 65-70.degree. C. for about 2 hrs to form a precursor 
solution. In another round bottom flask, an amount of 14.6 g of the silica 
(Chemical A) was slurried in THF before adding the precursor composition 
for impregnation. The mixture was mixed for about 30 min at a temperature 
of 50.degree. C. under N.sub.2 atmosphere, then dried at about 
50-70.degree. C. under very low vacuum. A dry free-flowing solid of the 
silica impregnated precursor containing 12.7 weight percent of THF was 
obtained (Chemical B). 
Example 1--Comparative 
4 grams of Chemical B was slurried with hexane at 30.degree. C. in a 
roundbottom flask using a magnetic stirrer under a nitrogen blanket. 8.4 
ml of a 20% solution of diethyl aluminum chloride (DEAC) in hexane was 
added to the slurry and mixed at 30.degree. C. for 30 minutes. 3.5 ml of 
20% solution of tri-n-hexyl aluminum (TnHAL) in hexane was added to the 
mixture and mixed at 30.degree. C. for 30 minutes to give a 0.70 Al/THF 
molar ratio. This mixture was dried for 2 hours at a temperature of about 
70.degree. C. to yield a dry free-flowing solid (Catalyst A). 
Slurry Homo-Polymerization 
Polymerization was performed in the slurry phase in a 2-liter autoclave 
reactor equipped with magnetic drive agitation, an external water jacket 
for temperature control, catalyst injection pump and gas feed streams for 
hydrogen, nitrogen and ethylene. The reactor was baked for 90 minutes at 
150.degree. C., and then purged repeatedly with nitrogen. 900 ml of hexane 
was added into the reactor, followed by about 3 ml of triethylaluminum 
(TEAL) as a co-catalyst in order to maintain the Al/Ti ratio at about 50. 
The reactor contents were stirred at 50.degree. C. for 5 min and 0 psig 
nitrogen pressure. Hydrogen was fed to raise the reactor pressure to 45 
psig", and then the pressure in the reactor was increased to 220 psig with 
ethylene. The temperature of the vessel was raised to 80.degree. C. and 
0.24 grams of the Catalyst A (0.06 Mm Ti) was injected into the reactor 
using the high pressure injection pump. The resultant polymerization was 
continued for 60 minutes while maintaining the reaction vessel at 
85.degree. C. and 220 psig by constant ethylene flow. The resultant 
polyethylene had a weight average molecular weight of 151,000, a number 
average molecular weight of 46,000, a molecular weight distribution of 3.3 
and bulk density of 0.42 gm/cc. The polymerization activity was 1,033 gm 
polymer/gm catalyst. 
Example 2 
4 grams of Chemical B were slurried with hexane at 30.degree. C. under a 
nitrogen blanket in a roundbottom flask using a magnetic stirrer. 3 ml of 
30% solution of methyl aluminoxane (MAO) in toluene was added to the 
slurry and mixed at room temperature for 30 minutes to give a 0.72 Al/THF 
molar ratio. This mixture was dried for 2 hours at about 70.degree. C. to 
provide a dry free-flowing solid (Catalyst B). Polymerization was 
performed with Catalyst B using the method set forth in Example 1. The 
resultant polyethylene had a bulk of 0.36 gm/cc. The polymerization 
activity was 1,396 gm polymer/gm catalyst. 
Example 3 
4 grams of Chemical B were slurried with hexane at 30.degree. C. under a 
nitrogen blanket in a roundbottom flask using a magnetic stirrer. 0.78 ml 
of a 30% solution of MAO in toluene was added to the slurry and mixed at 
30.degree. C. for 30 minutes, and 1.55 ml of a 20% solution of tri-n-hexyl 
aluminum (TnHAL) in hexane was added to the mixture and stirred at 
30.degree. C. for 30 minutes to give a 0.47 MAO/THF molar ratio and a 0.23 
TnHAL/THF molar ratio. This mixture was dried for 2 hours at a temperature 
of about 70.degree. C. to provide a dry free-flowing solid (Catalyst C). 
Polymerization was performed with Catalyst C. as in Example 1. 
The resultant polyethylene had a weight average molecular weight of 
137,000, a number average molecular weight of 33,500, a molecular weight 
distribution of 4.1 and bulk density of 0.36 gm/cc. The polymerization 
activity was 1,291 gm polymer/gm catalyst. 
Example 4 
4 grams of Chemical B was slurried with hexane at 30.degree. C. under 
N.sub.2 in a roundbottom flask using a magnetic stirrer. 1.55 ml of 30% 
solution of MAO in toluene was added to the slurry and mixed at 30.degree. 
C. for 30 minutes, and then 3.11 ml of 20% solution of tri-n-hexyl 
aluminum (TnHAL) in hexane was added to the mixture and mixed at 
30.degree. C. for 30 minutes to give a 0.23 MAO/THF molar ratio and a 0.47 
TnHAL/THF molar ratio. This mixture was dried for 2 hours at about 
70.degree. C. to provide a dry free-flowing solid (Catalyst D). 
Polymerization was performed with Catalyst D as in Example 1. The 
resultant polyethylene had a bulk density of 0.36 gm/cc. The 
polymerization activity was 1,104 gm/gm catalyst. 
Example 5 
4 grams of Chemical B was slurried with hexane at 30.degree. C. under 
N.sub.2 in a roundbottom flask using a magnetic stirrer. An amount of 6 ml 
of 30% solution of MAO in toluene was added to the slurry and mixed at 
room temperature for 30 minutes to give a 1.44 Al/THF molar ratio. This 
mixture was dried for 2 hours at about 70.degree. C. to provide a dry 
free-flowing solid (Catalyst E). Polymerization was performed with 
Catalyst E as in Example 1 with the exception that 0.12 gm of the catalyst 
E was injected and a 55 Al/Ti molar ratio was used. The resultant 
polyethylene had a weight average molecular weight of 116,000, a number 
average molecular weight of 26,800, a molecular weight distribution of 4.3 
and bulk density of 0.35 gm/cc. The polymerization activity was 1,467 
gm/gm catalyst. 
Example 6 
4 grams of Chemical B was slurried with hexane at 30.degree. C. under 
N.sub.2 in a roundbottom flask using a magnetic stirrer. An amount of 6.66 
ml of 30% solution of MAO in toluene was added to the slurry and mixed at 
room temperature for 30 minutes to give a 3.0 Al/THF molar ratio. This 
mixture was dried for 3 hours at about 70.degree. C. to provide a dry 
free-flowing solid (Catalyst F). Polymerization was performed with 
Catalyst F as in Example 1 with the exception that a 29 Al/Ti molar ratio 
was used. The resultant polyethylene had a weight average molecular weight 
of 146,000, a number average molecular weight of 34,000, a molecular 
weight distribution of 4.3 and bulk density of 0.37 gm/cc. The 
polymerization activity was 859 gm/gm catalyst. 
Example 7 
4 grams of Chemical B was slurried with hexane at 30.degree. C. under 
N.sub.2 in a roundbottom flask using a magnetic stirrer. An amount of 
13.33 ml of 30% solution of MAO in toluene was added to the slurry and 
mixed at room temperature for 30 minutes to give a 6.0 Al/THF molar ratio. 
This mixture was dried for 3 hours at about 80.degree. C. to provide a dry 
free-flowing solid (Catalyst G). Polymerization was performed with 
Catalyst G as in Example 6. The resultant polyethylene had a weight 
average molecular weight of 143,000, a number average molecular weight of 
31,300, a molecular weight distribution of 4.6 and bulk density of 0.37 
gm/cc. The polymerization activity was 1,277 gm/gm catalyst. 
Example 8 
4 grams of Chemical B was slurried with hexane at 30.degree. C. under 
N.sub.2 in a roundbottom flask using a magnetic stirrer. An amount of 24 
ml of 30% solution of MAO in toluene was added to the slurry and mixed at 
room temperature for 30 minutes to give a 14.37 Al/THF molar ratio. This 
mixture was dried for 2 hours at a temperature of about 70.degree. C. to 
provide a dry free-flowing solid (Catalyst H). Polymerization was 
performed with Catalyst H as in Example 1. The polymerization activity was 
208 gm/gm catalyst. 
Example 9 
4 grams of Chemical B was slurried with hexane at 30.degree. C. under 
N.sub.2 in a roundbottom flask using a magnetic stirrer. 1.5 ml of 30% 
solution of MAO in toluene was added to the slurry and mixed at room 
temperature for 30 minutes to give a 0.36 Al/THF molar ratio. This mixture 
was dried for 2 hours at about 70.degree. C. to provide a dry free-flowing 
solid (Catalyst I). Polymerization was performed with Catalyst I as in 
Example 1. The resultant polyethylene had a weight average molecular 
weight of 120,000, a number average molecular weight of 28,500, a 
molecular weight distribution of 4.2 and bulk density of 0.38 gm/cc. The 
polymerization activity was 1,396 gm/gm catalyst. 
Example 10 
Polymerization was performed with Catalyst I as in Example 1 with the 
exception that 15 psig hydrogen was fed into the reactor and a temperature 
of 75-85.degree. C. was employed. The resultant polyethylene had a weight 
average molecular weight of 611,000, a number average molecular weight of 
67,800, a molecular weight distribution of 8.0 and bulk density of 0.36 
gm/cc. The polymerization activity was 1,996 gm/gm catalyst. 
Example 11 
4 grams of Chemical B was slurried with hexane at 30.degree. C. under 
N.sub.2 in a roundbottom flask using a magnetic stirrer. An amount of 0.35 
ml of 30% solution of MAO in toluene was added to the slurry and mixed at 
room temperature for 30 minutes to give a 0.2 Al/THF molar ratio. This 
mixture was dried for 2 hours at about 70.degree. C. to provide a dry 
free-flowing solid (Catalyst J). Polymerization was performed with 
Catalyst J as in Example 1. The resultant polyethylene had a weight 
average molecular weight of 102,000, a number average molecular weight of 
23,100, a molecular weight distribution of 4.4 and bulk density of 0.39 
gm/cc. The polymerization activity was 1,942 gm/gm catalyst. 
Example 12 
4 grams of Chemical B was slurried with hexane at 30.degree. C. under 
N.sub.2 in a roundbottom flask using a magnetic stirrer. 0.22 ml of 30% 
solution of MAO in toluene was added to the slurry and mixed at room 
temperature for 30 minutes to give a 0.1 Al/THF molar ratio. This mixture 
was dried for 2 hours at about 70.degree. C. to provide a dry free-flowing 
solid (Catalyst K). Polymerization was performed with Catalyst K as in 
Example 1. The resultant polyethylene had a weight average molecular 
weight of 110,000, a number average molecular weight of 27,000, a 
molecular weight distribution of 4.2 and bulk density of 0.38 gm/cc. The 
polymerization activity was 1,359 gm/gm catalyst. 
Example 13--Comparative 
4 grams of Chemical B was slurried with hexane at 30.degree. C. under 
N.sub.2 in a roundbottom flask using a magnetic stirrer. 2.5 ml of 20% 
solution of diethyl aluminum chloride (DEAC) in hexane was added to the 
slurry and mixed at 30.degree. C. for 30 minutes. An amount of 1.75 ml of 
20% solution of tri-n-hexyl aluminum (TnHAL) in hexane was then added to 
the mixture and mixed at 30.degree. C. for 30 minutes to give a 0.25 
Al/THF molar ratio. This mixture was dried for 2 hours at about 70.degree. 
C. to provide a dry free-flowing solid (Catalyst L). 
Polymerization was performed with Catalyst L identically as in Example 1. 
The resultant polyethylene had a bulk density of 0.38 gm/cc. The 
polymerization activity was 1,150 gm/gm catalyst. 
Example 14--Comparative 
4 grams of Chemical B was slurried with hexane at 30.degree. C. under 
N.sub.2 in a roundbottom flask using a magnetic stirrer. An amount of 1.7 
ml of 20% solution of diethyl aluminum chloride (DEAC) in hexane was added 
to the slurry and mixed at 30.degree. C. for 30 minutes. An amount of 3.5 
ml of 20% solution of tri-n-hexyl aluminum (TnHAL) in hexane was then 
added to the mixture and mixed at 300.degree. C. for 30 minutes to give a 
0.30 Al/THF molar ratio. This mixture was dried for 2 hours at about 
70.degree. C. to provide a dry free-flowing solid (Catalyst M). 
Slurry Co-Polymerization 
Polymerization was performed in the slurry phase in a 2-liter autoclave 
reactor equipped with magnetic drive agitation, an external water jacket 
for temperature control, a catalyst injection pump and gas feed streams 
(hydrogen, nitrogen and ethylene). The reactor was heated for 90 minutes 
at 150.degree. C., and then pressurized and depressurized with N.sub.2 
several times. 900 ml of hexane was added into the reactor, followed by 
about 3 ml of triethylaluminum (TEAL) as a co-catalyst to maintain a Al/Ti 
ratio of about 53. The reactor contents were stirred at 50.degree. C. for 
5 min and 0 psig nitrogen pressure. 10 ml of hexene-1 was injected after 
the TEAL solution. Hydrogen was fed to increase the reactor pressure to 45 
psi". The reactor was then pressurized to 220 psig with ethylene. The 
reaction vessel temperature was then raised to 80.degree. C. An amount 
0.09 gm of the Catalyst M (0.02 Mm Ti) was injected into the reactor using 
the high pressure injection pump. The polymerization was continued for 60 
minutes while maintaining the reaction vessel at 850.degree. C. and 220 
psig with constant ethylene flow. 270 grams of polyethylene was recovered. 
The polyethylene had a branching frequency of 0.5 per 1000 C atoms, 
hexene-1 of 0.09% mole and a density of 0.9560 gm/cc. The polymerization 
activity was 3,000 gm/gm catalyst. 
Example 15 
Polymerization was performed with Catalyst J (Example 11) as in Example 13. 
The resultant polyethylene had a branching frequency of 0.4 per 1000 C 
atoms, hexene-1 of 0.08% mole and a density of 0.9548 gm/cc. The 
polymerization activity was 3,500 gm/gm catalyst. 
Example 16 
Polymerization was performed with Catalyst I (Example 9) as in Example 13. 
The resultant polyethylene had a branching frequency of 0.4 per 1000 C 
atoms, hexene-1 of 0.08% mole and a density of 0.9556 gm/cc. The 
polymerization activity was 4,225 gm/gm catalyst. 
Example 17--Comparative 
Polymerization was performed employing Catalyst M (Example 14) as in 
Example 13 with the exception that 20 ml of hexene-1 was injected into the 
reactor. The resultant polyethylene had a branching frequency of 0.7 per 
1000 C atoms, hexene-1 of 0.14% mole and a density of 0.9534 gm/cc. The 
polymerization activity was 3,211 gm/gm catalyst. 
Example 18 
Polymerization was performed with Catalyst J (Example 11) as in Example 13 
with the exception that 20 ml of hexene-1 was injected into the reactor. 
The resultant polyethylene had a branching frequency of 0.17 per 1000 C 
atoms, hexene-1 of 0.14% mole and a density of 0.9540 gm/cc. The 
polymerization activity was 4,063 gm/gm catalyst. 
Example 19 
Polymerization was performed with Catalyst I (Example 9) as in Example 13 
with the exception that 20 ml of hexene-1 was injected into the reactor. 
The resultant polyethylene had a branching frequency of 0.6 per 1000 C 
atoms, hexene-1 of 0.12% mole and a density of 0.9524 gm/cc. The 
polymerization activity was 3,750 gm/gm catalyst. 
Example 20--Comparative 
Polymerization was performed employing Catalyst M (Example 14) as in 
Example 13 with the exception that 30 ml of hexene-1 was injected into the 
reactor. The resultant polyethylene had a branching frequency of 1.4 per 
1,000 C atoms, hexene-1 of 0.28% mole and a density of 0.9518 gm/cc. The 
polymerization activity was 3,422 gm/gm catalyst. 
Example 21 
Polymerization was performed with Catalyst J (Example 11) as in Example 13 
with the exception that 30 ml of hexene-1 was injected into the reactor. 
The resultant polyethylene had a branching frequency of 1.2 per 1,000 C 
atoms, hexene-1 of 0.23% mole and a density of 0.9492 gm/cc. The 
polymerization activity was 3,888 gm/gm catalyst. 
Example 22 
Polymerization was performed with Catalyst I (Example 9) as in Example 13 
with the exception that 30 ml of hexene-1 was injected into the reactor. 
The resultant polyethylene had a branching frequency of 1.10 per 1,000 C 
atoms, hexene-1 of 0.19% mole and a density of 0.9506 gm/cc. The 
polymerization activity was 3,938 gm/gm catalyst. 
Example 23--Comparative 
Polymerization was performed employing Catalyst M (Example 14) as in 
Example 13 with the exception that 60 ml of hexene-1 was injected into the 
reactor. The resultant polyethylene had a branching frequency of 2.7 per 
1,000 C atoms, hexene-l of 0.54% mole and a density of 0.9464 gm/cc. The 
polymerization activity was 2,733 gm/gm catalyst. 
Example 24 
Polymerization was performed with Catalyst J (Example 11) as in Example 13 
with the exception that 60 ml hexene-1 was injected into the reactor. The 
resultant polyethylene had a branching frequency of 1.7 per 1,000 C atoms, 
hexene-1 of 0.33% mole and a density of 0.9484 gm/cc. The polymerization 
activity was 4,313 gm/gm catalyst. 
Example 25 
Polymerization was performed with Catalyst I (Example 9) as in Example 13 
with the exception that 60 ml of hexene-1 was injected into the reactor. 
The resultant polyethylene had a branching frequency of 1.7 per 1,000 C 
atoms, hexene-1 of 0.34% mole and a density of 0.9478 gm/cc. The 
polymerization activity was 4,288 gm/gm catalyst. 
Example 26--Comparative 
Polymerization was performed employing Catalyst M (Example 14) as in 
Example 13 with the exception that 80 ml of hexene-1 was injected into the 
reactor. The resultant polyethylene had a branching frequency of 2.9 per 
1,000 C atoms, hexene-1 of 0.57% mole and a density of 0.9424 gm/cc. The 
polymerization activity was 2,833 gm/gm catalyst. 
Example 27 
Polymerization was performed with Catalyst J (Example 11) as in Example 13 
with the exception that 80 ml of hexene-1 was injected into the reactor. 
The resultant polyethylene had a branching frequency of 2.2 per 1,000 C 
atoms, hexene-1 of 0.57% mole and a density of 0.9454 gm/cc. The 
polymerization activity was 3,950 gm/gm catalyst. 
Example 28 
Polymerization was performed with Catalyst I (Example 9) as in Example 13 
with the exception that 80 ml of hexene-1 was injected into the reactor. 
The resultant polyethylene had a branching frequency of 2.6 per 1,000 C 
atoms, hexene-1 of 0.52% mole and a density of 0.9442 gm/cc. The 
polymerization activity was 4,538 gm/gm catalyst. 
TABLE I 
__________________________________________________________________________ 
Reaction Conditions For Examples 1 to 13 
Bulk 
Activators 
Catalyst 
Total 
Temp Activity 
density 
Example 
Activator 
Ratio 
(gm) 
Al/THF 
Al/Ti 
.degree. C. 
Yield gm 
gm/gm 
gm/cc 
Mw MWD 
__________________________________________________________________________ 
1* DEAC/TnHAL 
0.50/0.20 
0.24 
0.70 
50 85 248 1033 
0.42 
151000 
3.3 
2 MAO 0.24 
0.72 
50 85 335 1396 
0.36 
-- -- 
3 MAO/TnHAL 
0.47/0.23 
0.24 
0.70 
50 85 310 1291 
0.36 
137000 
4.1 
4 MAO/TnHAL 
0.23/0.47 
0.24 
0.70 
55 85 265 1104 
0.37 
-- -- 
5 MAO 0.12 
1.44 
55 85 176 1467 
0.35 
116000 
4.3 
6 MAO 0.22 
3.00 
29 85 189 859 
0.37 
146000 
4.3 
7 MAO 0.22 
6.00 
29 85 281 1277 
0.37 
143000 
4.6 
8 MAO 0.24 
14.37 
50 85 50 208 
-- -- -- 
9 MAO 0.24 
0.36 
53 85 335 1396 
0.38 
120000 
4.2 
10 MAO 0.24 
0.36 
53 75 479 1996 
0.36 
611000 
8.0 
11 MAO 0.24 
0.20 
53 85 466 1942 
0.39 
102000 
4.4 
12 MAO 0.22 
0.10 
55 85 298 1355 
0.38 
110000 
4.2 
13* DEAC/TnHAL 
0.15/0.1 
0.24 
0.25 
55 85 276 1150 
0.38 
-- -- 
__________________________________________________________________________ 
*Comparative Example 
TABLE II 
__________________________________________________________________________ 
Reaction Conditions For Examples 14 to 28 
Branch 
Activators 
Catalyst 
Hexene-1 
Total 
Temp. 
Yield 
Activity 
Density 
Frequency/ 
Hexene 
Example 
Activator 
Ratio 
gm. Al/THF 
mc Al/ti 
.degree. C. 
gm gm/gm 
gm/cc 
1000 
mole 
__________________________________________________________________________ 
% 
14* DEAC/TnHAL 
0.10/0.20 
0.09 
0.30 
10 53 85 270 3000 0.9560 
0.5 0.09 
15 MAO 0.08 
0.20 
10 53 85 280 3500 0.9548 
0.4 0.08 
16 MAO 0.08 
0.36 
10 53 85 338 4225 0.9556 
0.4 0.08 
17 DEAC/TnHAL 
0.10/0.20 
0.09 
0.30 
20 53 85 289 3211 0.9534 
0.7 0.14 
18 MAO 0.08 
0.20 
20 53 85 325 4063 0.9540 
0.7 0.14 
19 MAO 0.08 
0.36 
20 53 85 300 3750 0.9524 
0.6 0.12 
20 DEAC/TnHAL 
0.10/0.20 
0.09 
0.30 
30 53 85 308 3422 0.9518 
1.4 0.28 
21 MAO 0.08 
0.20 
30 53 85 311 3888 0.9492 
1.2 0.23 
22 MAO 0.08 
0.36 
30 53 85 315 3938 0.9506 
1.0 0.19 
23* DEAC/TnHAL 
0.10/0.20 
0.09 
0.30 
60 53 85 246 2733 0.9464 
2.7 0.54 
24 MAO 0.08 
0.20 
60 53 85 345 4313 0.9484 
1.7 0.33 
25 MAO 0.08 
0.36 
60 53 85 343 4288 0.9478 
1.7 0.34 
26* DEAC/TnHAL 
0.10/0.20 
0.09 
0.30 
80 53 85 255 2833 0.9424 
2.9 0.57 
27 MAO 0.08 
0.20 
80 53 85 316 3950 0.9454 
2.2 0.57 
28 MAO 0.08 
0.36 
80 53 85 363 4538 0.9442 
2.6 0.52 
__________________________________________________________________________ 
*Comparative Example 
Referring to Table I, Examples 1-4 show that using MAO as an activator 
(Example 2) instead of using DEAC/TnHAL (Example 1) leads to an increase 
in the activity by 26% accompanied with a decrease in the bulk density by 
14.3%. Using (MAO/TnHAL) (Examples 3 and 4) as an activator instead of 
DEAC/TnHAL also leads to an increase in activity by 20% and an increase in 
MWD by 20%. 
Examples 5-12 show that increasing the Activator/THF molar ratio from 0.1 
up to 0.36 leads to an increase in the catalyst activity by 47%, after 
which the activity decreased with further increase in the activator/THF 
molar ratio. The increase in activity was about 32% when the Activator/THF 
molar ratio increased from 0.1 to 0.36. Also, MWD increased by 47% when 
the Activator/THF molar ratio increased from 0.1 to 0.36. The activity 
decreased significantly by about 90% when the Activator/THF molar ratio 
further increased from 0.36 up to 14.37. MWD decreased by 43% with further 
increase in Activator/THF molar ratio from 0.36 to 6.00. 
Referring to Table II, Examples 14, 17, 20, 23 and 26 show that when using 
DEAC/TnHAL as an activator, the activity of the catalyst increased by 12% 
when the amount of hexene-1 comonomer increased from 10 ml to 30 ml, after 
which the activity decreased and remained constant with further increase 
in the comonomer concentration. 
When using MAO as the activator for the catalyst (Examples 15, 16, 18, 19, 
21, 22, 24, 25, 27 and 28), activity increased gradually by increasing the 
concentration of hexene-1 comonomer wherein the activity increased by 19% 
when the hexene-1 concentration increased from 10 to 60 ml. 
An increase in the hexene-1 comonomer concentration when using DEAC/TnHAL 
as an activator caused a sharp decrease in the density of the produced 
polymer wherein the density decreased from 0.9560 to 0.9424 when the 
hexene concentration increased from 10 to 80 ml. 
On the other hand, an increase in the hexene-1 concentration when using MAO 
as an activator caused a gradual decrease in the density of the produced 
polymer wherein the density decreased from 0.9548 to 0.9454. 
An increase in the hexene comonomer concentration when using DEAC/TnHAL as 
an activator led to a significant increase in the hexene % content in the 
produced polymer. Hexene % increased from 0.09 mol % to 0.54 mol % at 10 
and 60 ml of hexene, respectively. 
Increasing hexene concentration while using MAO caused a gradual increase 
in the hexene % content in the produced polymer wherein the hexene % 
increased from 0.08 mol % to 0.33 mol % at 10 and 60 ml of hexene, 
respectively. 
As can be seen by the Examples, using MAO as an activator during the 
catalyst preparation process increases the catalyst activity in general, 
the incorporation of the comonomer and the MWD of the produced polymer. 
The above description of the invention is intended to be illustrative and 
not limiting. Various changes or modifications in the embodiments 
described may occur to those skilled in the art. These can be made without 
departing from the spirit or scope of the invention.