Deactivator for olefin polymerization catalyst

A method is disclosed for controlling the activity of or deactivating a transition element olefin polymerization catalyst by contacting the catalyst with a deactivating polymer comprising a homopolymer of an unsaturated polar organic compound or a copolymer of an alpha-olefin and an unsaturated polar organic compound.

DESCRIPTION 
1. Technical Field 
The present invention relates to a method for deactivating Ziegler-Natta or 
transition element oxide polymerization catalysts. 
2. Prior Art 
Various processes are known for deactivation of Ziegler-Natta catalysts 
such as described by Zboril in U.S. Pat. No. 4,430,488 who discloses a 
salt of an alkaline earth metal or zinc and an aliphatic monocarboxylic 
acid dissolved in a hydrocarbon solvent may be employed for this purpose. 
Machon et al. similarly disclose in U.S. Pat. No. 4,105,609 that a 
Ziegler-Natta catalyst used for the preparation of polyethylene in a high 
temperature high pressure process can be deactivated at the end of the 
reaction by means of an alkali metal salt or alkaline earth metal salt of 
a carboxylic acid. 
The deactivation of Ziegler-Natta catalysts is disclosed by Cupples et al. 
in U.S Pat. No. 3,876,600 in which flux-calcined diatomite is employed to 
deactivate and insolubilize the aluminum and titanium components of the 
catalyst after which the insolubilized aluminum and titanium are filtered 
from the polymer. 
Dietrich et al. U.S. Pat. No. 3,708,465 describe a method for the 
deactivation of a Ziegler catalyst containing alkyl groups and hydride 
groups bonded to aluminum and a heavy metal component such as titanium by 
means of an alcohol which reacts with the alkyl and/or hydride groups 
before the heavy metal component. 
Bacskai discloses in U.S. Pat. No. 3,520,866 that an alkanol solution of an 
alkali metal alkoxide can be employed to deactivate Ziegler-Natta 
catalysts employed for the polymerization of propylene in the presence of 
a hydrocarbon solvent. 
SUMMARY OF THE INVENTION 
The present invention relates to a method for controlling the activity of 
or deactivating an olefin polymerization catalyst, such as a Ziegler-Natta 
transition element catalyst or a transition element oxide olefin 
polymerization catalyst comprising contacting the catalyst with a 
deactivating polymer of an unsaturated polar organic compound i.e., a 
polymer comprising a homopolymer of an unsaturated polar organic compound 
or a copolymer of an alpha-olefin and an unsaturated polar organic 
compound. 
The invention also relates to a method for the preparation of polyolefins 
at elevated pressures by polymerizing alpha-olefins in the presence of a 
Ziegler-Natta catalyst based on a transition element or a transition 
element oxide catalyst whereby the polyolefin contains the catalyst in an 
active state. The catalyst is deactivated or catalyst activity is 
controlled by contacting the polyolefin containing the catalyst in an 
active state with a deactivating polymer after the alpha-olefin has been 
polymerized. The deactivating polymer of an unsaturated polar organic 
compound comprises a homopolymer of an unsaturated polar organic compound 
or a copolymer of an alpha-olefin and an unsaturated polar organic 
compound such as an unsaturated ester and the like. 
DETAILED DESCRIPTION OF THE INVENTION 
Although Ziegler-Natta catalysts or olefin polymerization catalysts based 
on transition element oxides may be employed at ambient pressures and 
above (e.g., 1 to about 50 atmospheres) for the polymerization of 
alpha-olefins, catalysts of this type are also employed in high pressure 
processes such as in the production of linear low density polymers of 
alpha-olefins including polyethylene, polypropylene, polybutylene, 
copolymers thereof and the like. These processes are generally conducted 
at pressures from about 25 to about 35,000 psig and employ olefin 
polymerization conditions similar to those used prior to the discovery of 
the Ziegler-Natta catalysts. 
In the high pressure processes employing these catalysts, the polymer 
obtained has to be processed through a "let-down" step in which the 
polymer is brought to ambient conditions of temperature and pressure and 
the residual alpha-olefin monomer, if any, is stripped from the polymer. 
The "let-down" procedure is employed in continuous, semi-continuous and 
batch polymerization processes. In the continuous and semi-continuous 
processes, the polymer obtained from the process is introduced into a 
let-down vessel by means of a conduit, after which residual monomer is 
removed from the polymer and returned to the polymerization process. 
It is essential, prior to, or as part of, the let-down step, and especially 
in the continuous and semicontinuous processes where a let-down vessel is 
employed that any active catalyst remaining in the polymer be deactivated, 
otherwise there is a danger that further polymerization will take place 
and cause temperature and pressure rises. In any event, it is essential in 
order to control the molecular weight and molecular weight distribution of 
the polymer that the polymerization be terminated at as nearly a precise 
end point as possible in order to avoid production of polymers that are 
excessively high or low in molecular weight and contain a molecular weight 
distribution that is not desired in the end product. 
The explosion hazards presented by the continued reaction of monomer during 
the let-down process in some instances can lead to line rupture and/or 
tank rupture and can therefore be extremely dangerous. 
For these reasons, the prior art has employed deactivators for this type of 
catalyst, some of which have been described above. These deactivators in 
some instances contain inorganic materials which may not be desirable in 
the polymer produced and are removed along with the catalyst (of. U.S. 
Pat. No. 3,876,600). 
In some prior art continuous or semi-continuous processes, a liquid 
deactivator is employed and is removed from the polymer along with 
unreacted alpha-olefin monomer. Prior to recycling the alpha-olefin 
monomer for subsequent polymerization, the liquid deactivator has to be 
removed, usually by a distillation or stripping process. If the separation 
is not efficient, the liquid deactivator is recycled back to the reactor 
along with unreacted alpha-olefin. The polymerization catalyst in the 
polymerization reactor is thereby deactivated by the recycle to some 
degree before the polymerization is completed. 
Gas-phase polymerization of olefins is described in the U.S. Pat. Nos. to 
Dormenval et al., 3,922,322; Jezl et al., 3,965,083; Jezl et al., 
3,970,611; Peters et al., 3,971,768; Miller, 4,003,712; Levine et al., 
4,011,382; and Jezl et al. 4,129,701, all of which are incorporated herein 
be reference. 
The Standard Oil gas-phase process as described by Jezl et al. and Peters 
employs a horizontal stirred reactor having several compartments which 
form a bed. This bed has a series of longitudinally extending paddles that 
are rotated at a relatively low speed. The monomer such as ethylene or its 
equivalents, hydrogen (employed for molecular weight control) and a 
recycle gas stream are injected into the bottom of each one of the 
compartments. The injection velocity of these components is low enough so 
that the bed will not be fluidized. Several openings are provided along 
the top of the reactor through which a quench stream and catalyst 
components are injected. A relatively low molecular weight hydrocarbon 
such as isopentane or butane is employed as the quench stream and may 
optionally contain a liquid comonomer such as those described herein for 
the manufacture of LLD polymers. 
It should be noted in this regard that the gas phase process allows for the 
production of LLD polymers at pressures considerably less than the 
approximate 10,000 psig to about 30,000 psig pressures employed in the so 
called high pressure process. 
One of the difficulties with the gas-phase process is the high activity of 
the catalyst and the resultant problems with so called hot-spots. In the 
Standard Oil process, the problem of hot-spots is prevented by the quench 
stream which cools the reaction mass by evaporation. Without this cooling 
process, the reaction mass would be converted into molten polymer which 
would coat the walls of the reactor and plug the various inlet and polymer 
discharge orifices. 
In the Standard Oil process, the series of paddles in the reactor keep the 
reaction mass agitated. This mass grows as a result of the polymerization 
reaction and is transported from one compartment to another and is finally 
discharged at the end of the reactor. Unreacted monomer and quench stream 
components are removed from the reaction mass, separated and recycled as 
separate streams to the reactor. 
The Standard Oil process generally employs a highly active titanium 
catalyst on a support in combination with a triethyl aluminum cocatalyst. 
The Naphtachimie and Union Carbide gas phase process are described in the 
aforementioned U.S. patent to Levine et al., Miller and Dormenvale. These 
processes differ from the Standard Oil process in that a vertical 
fluidized bed reactor is employed. Problems are also encountered due to 
the high activity of the catalyst which causes hot-spots and the formation 
of molten polymer in the reaction. If not controlled, the molten polymer 
not only coats out on the walls of the reactor but also tends to plug the 
various inlet and outlet openings. The formation of hot-spots is avoided 
by controlling the fluidized bed so that it always contains polymer 
particles (i.e. newly formed particles and growing polymer particles). 
In the fluidized bed process the monomer stream that passes through the bed 
but is not reacted moves upwardly in the reactor toward what is described 
as a disengagement zone, or portion of the reactor that expands outwardly 
and upwardly resulting in a reduction of gas and particle velocity. As a 
result, most of the particles fall back into the bed. Unreacted monomer is 
taken off as a recycle gas and fed into the bottom of the reactor along 
with gas feed. 
The catalyst is fed seperately into the reactor and the rate of catalyst 
addition controls the polymerization rate as well as the amount of heat 
that is generated in the fluidized bed. The reaction can therefore be 
controlled by analyzing the temperature of the gas stream exiting the 
reactor and adjusting the rate of catalyst addition. The typical 
polymerization catalyst employed comprises chromium oxide containing 
titanium and fluoride. 
The process generally runs at about 85.degree. to about 95.degree. C. and 
at a pressure from about 250 to about 325 psi. 
One of the advantages of employing a gas-phase reaction process is that the 
product obtained does not have to be separated from any solvent such as is 
required in a slurry process. 
Accordingly, it is an object of the present invention to overcome these and 
other difficulties and to achieve the various objectives of the prior art. 
It is a further object of the present invention to provide a method for 
deactivating a Ziegler-Natta or a transition element oxide catalyst. 
It is also an object of the present invention to provide a method for 
deactivating a Ziegler-Natta or a transition element oxide olefin 
polymerization catalyst with a non-volatile deactivator. 
It is a further object of the present invention to provide a method for 
deactivating a Ziegler-Natta or a transition element oxide catalyst with a 
deactivator that would not be recycled to an olefin polymerization process 
with the recycle of unreacted olefin monomer. 
It is also an object of the present invention to provide a deactivator for 
a Ziegler-Natta or transition element oxide olefin polymerization catalyst 
that does not have to be removed from the polymer obtained. 
It is also an object of the present invention to provide a deactivator for 
a Ziegler-Natta or transition element oxide catalyst that is not an 
inorganic material and that may remain in the polymer obtained. 
It is also an object of the invention to control hot spots in gas-phase 
olefin polymerization processes. 
These and other objects have been achieved according to the present 
invention in which a method is provided for deactivating or controlling 
the activity of a Ziegler-Natta transition element olefin polymerization 
catalyst or transition element oxide olefin polymerization catalyst 
comprising contacting the catalyst with a deactivating polymer of an 
unsaturated polar organic compound i.e., a polymer comprising a 
homopolymer of an unsaturated polar organic compound or a copolymer of an 
alpha-olefin and an unsaturated polar organic compound. 
In one embodiment, a method is provided for the preparation of polyolefins 
at elevated pressures by polymerizing alpha-olefins in the presence of a 
Ziegler-Natta catalyst based on a transition element or transition element 
oxide catalyst whereby the polyolefin contains the catalyst in an active 
state. This catalyst is deactivated or catalyst activity is controlled by 
contacting the polyolefin containing the catalyst in the active state with 
a deactivating polymer after the alpha- olefin has been polymerized. The 
deactivating polymer comprises a polymer of an unsaturated organic polar 
compound i.e., a polymer comprising a homopolymer of an unsaturated polar 
organic compound or a copolymer of an alpha-olefin and an unsaturated 
polar organic compound. 
The deactivating polymer of the present invention is effective for the 
deactivation of Ziegler-Natta or transition element oxide catalysts which 
are employed in the polymerization of alpha-olefins. Ziegler-Natta 
catalysts are well known in the art and generally comprise 
electro-positive transition metals of Groups IV-VIII of the Periodic Table 
of the Elements and especially Ti, V, Cr and Zr. These transition elements 
are at a level of oxidation lower than the maximum. In one embodiment they 
are employed in combination with a compound containing carbon or hydrogen 
linked to a metal from Groups I-III of the Periodic Table of the Elements 
in addition to compounds based on the non-transition elements from Group 
IVA of the periodic table of the elements such as silicon (e.g., 
SiCl.sub.4) and Group IIA elements from the Periodic Table of the Elements 
e.g., magnesium. Catalysts of this type may be supported or unsupported, 
magnesium chloride comprising one of the support materials that may be 
employed, although other support materials may be used such as alumina, 
silica, zirconia and the like. 
In one embodiment of the invention, the Ziegler-Natta catalyst employed for 
olefin polymerization comprises about 0.35 moles Ti(OBu).sub.4 
(Bu.dbd.butyl), about 0.253 moles Mg and about 0.0458 moles MgCl.sub.2 as 
a support in combination with about 1.0 moles SiCl.sub.4 (a chlorinating 
agent). 
The deactivating polymer will also deactivate other similar olefin 
polymerization catalysts such as the oxides of the transition elements, 
e.g. V, Mo or W on alumina or another inert metal oxide and which are 
activated by reduction with hydrogen. Another example of olefin 
polymerization catalysts that may be deactivated according to the 
invention are the Phillips type, e.g. chromic oxide on silica-aluminum 
activated by oxidation with air at 500.degree. C. Polymerization is 
carried out in suspension or hydrocarbon solvents at 
50.degree.-200.degree. C. and from atmospheric to about 600 psi pressure 
and more employing these catalysts. 
The activity of the above catalyst is increased by the use of a co-catalyst 
such as aluminum alkyl, e.g., triethyl aluminum, tripropyl aluminum and 
the like. In the case of chromium catalyst, alkyl boranes such as triethyl 
borane, triisopropyl borane and the like or boron hydrides are more likely 
to be used as a co-catalyst. 
The deactivating polymer of the present invention is employed to deactivate 
Ziegler-Natta or transition element oxide catalysts that are utilized in 
the high pressure polymerization of olefins such as for example the 
preparation of linear low density (LLD) poly-olefins. These polymers are 
prepared at pressures from about 10,000 psig to about 30,000 psig and 
especially from about 15,000 psig to about 25,000 psig. The temperature of 
the polymerization is from about 150.degree. C. to about 270.degree. C. 
and especially from about 200.degree. C. to about 240.degree. C. The 
olefin polymerization or the preparation of polyolefins according to the 
present invention includes the preparation of homopolymers or copolymers, 
based on alpha-olefins having from 2 to about 4 carbon atoms. The 
copolymers in this instance contain two or more different alpha-olefins. 
The copolymers prepared according to the present invention especially 
comprise the LLD type of copolymers containing high molecular weight 
alpha-olefins such as those alpha-olefins containing from about 5 to about 
12 carbon atoms in addition to one or more of the other aforesaid 
alpha-olefins such as ethylene and the like. 
The higher molecular weight alpha-olefins (e.g. those having from 5 to 
about 12 carbon atoms) are introduced into the polymer to increase 
branching along the polymer chain and thereby reduce density. LLD polymers 
are preferred in applications where the polymer is processed through a 
screw extruder for film formation, injection molding and the like since 
less energy is required than that for linear high density polyolefins 
processed through such apparatus. 
The olefin polymerization or polymerization of alpha-olefins according to 
the present invention may be either a batch, continuous or semicontinuous 
process. The copolymers that are formed in this respect may be either 
random, block or graft copolymers. 
The deactivating polymer is employed in the high pressure process by 
combining it with a polyolefin containing the aforesaid Ziegler-Natta or 
transition element oxide catalyst which is in an active state where the 
polyolefin has been polymerized either by a batch, continuous or 
semicontinuous method. Where the catalytic polymerization is conducted in 
a continuous or semicontinuous process, the polyolefin obtained is drawn 
off from the reactor through a conduit into a let-down tank so that 
unreacted monomer and other components employed in the polymerization, if 
any (e.g., solvent), can be stripped from the polymer and the product can 
be brought to ambient pressures and temperatures. The deactivating polymer 
may be injected into either the reactor, the conduit leading into the 
let-down tank or the let-down tank itself. The polyolefin containing the 
Ziegler-Natta or transition element oxide catalyst in an active state 
(e.g., LLD polymer) generally exits the reactor at about 240.degree. C. 
and the deactivating polymer may be injected into the hot polymer stream 
passing through the conduit into the let-down tank. The deactivating 
polymer may be preheated in order to improve mixing with the hot polymer 
stream. Additionally, the deactivating polymer may be blended with a 
polyolefin obtained from the Ziegler-Natta or transition element oxide 
catalyst polymerization in which the catalyst has been deactivated. This 
blending assures better mixing of the polyolefin containing active 
catalyst and deactivating polymer. The blend may then be injected into the 
polymer that is produced containing active Ziegler-Natta or transition 
element oxide catalyst, the blend optionally being preheated to further 
assure good mixing. 
The olefin component of the deactivating polymer in one embodiment may be 
substantially the same as the olefin component of the polymer containing 
the active Ziegler-Natta or transition element oxide catalyst that has to 
be deactivated. 
Additionally, the deactivating polymer when used in the high pressure 
process can be injected into the polymer containing active Ziegler-Natta 
or transition element oxide catalyst by dissolving the deactivating 
polymer in a solvent such as octane, decane, decalin and equivalent 
non-polar solvents which will not deactivate the catalyst; however, 
utilization of a solvent economically would require that the solvent be 
subsequently recovered and recycled which would make the process somewhat 
more costly than the direct injection of the deactivating polymer. Any 
solvent may be used in this respect which will not deactivate the 
Ziegler-Natta or transition element oxide catalyst. Solvents such as these 
are preferred since it minimizes the risk of deactivating the catalyst in 
the main reactor when unreacted olefin monomer is recycled to the main 
reactor with traces of solvent. 
The catalyst used in the gas phase polymerization processes may be combined 
with the deactivating polymers in sufficient amount to control catalyst 
activity and reduce hot-spots. This may be effected by mixing a finely 
divided deactivation polymer with the catalyst employed in the gas phase 
polymerization process or by dissolving the deactivating polymer in a 
solvent such as hexane and the like, combining it with the gas phase 
polymerization catalyst followed by removing the solvent from the catalyst 
that has been treated. Any drying process known in the art such as spray 
drying or evaporative drying employing a vacuum or drying at elevated 
temperatures or any combination of these conditions may be employed to 
effect solvent removal. Agglomeration of catalyst particles may be avoided 
by using dilute solutions of the deactivating polymer e.g. anywhere from 
about 1% to about 20% and especially from about 2% to about 10% of polymer 
in solvent. In addition to or as an alternative to combining the 
deactivating polymer with the gas phase polymerization catalyst, the 
deactivating polymer may be directly injected into the gas phase 
polymerization reactor during the polymerization reaction or 
intermittently in order to control the formation of hot-spots. 
It should be noted in this regard that the term gas-phase polymerization is 
a term that does not fully describe the process since the polymerization 
occurs on or within particles of polyolefins such as polyethylene 
contained in the polymerization vessel. In the Union Carbide and 
Naphtachimie processes, the reaction is started by charging the reactor 
and forming a fluidized bed of polyolefins such as polyethylene particles. 
This is done before the gas flow is started. After this bed of preformed 
polyethylene particles is converted into a fluidized bed by passing olefin 
gas such as ethylene gas through it, the catalyst is introduced and 
gradually a new fluidized bed is formed that displaces the old one, the 
new fluidized bed comprising a mixture of growing polymer particles and 
newly formed particles. Start up of the Standard Oil process is effected 
in substantially the same way; however, a fluidized bed is not used. 
Since polymer growth occurs within the particles of polyolefin, 
substituting the deactivating polymer of the present invention for the 
polymer particles produced comprises a novel means not only of controlling 
the rate of reaction of the olefin but also eliminating hot-spots in the 
gas-phase process. 
The deactivating polymers of the present invention comprise homopolymers 
based on an unsaturated polar organic compound and copolymers based on two 
or more monomers one of which is an alpha-olefin and the other of which is 
an unsaturated polar organic compound. The alpha-olefins employed in this 
aspect of the invention may contain anywhere from 2 to about 12 carbon 
atoms and especially 2 to about 4 carbon atoms and various mixtures 
thereof. Ethylene is an especially preferred alpha-olefin in this regard. 
The unsaturated polar organic compound preferably comprises an unsaturated 
ester such as a vinyl ester or an acrylic ester and especially a vinyl 
ester. 
These and other unsaturated polar organic compounds include: 
a. Vinyl esters of carboxylic acids such as vinyl formate, vinyl acetate, 
vinyl propionate, vinyl butyrate, vinyl benzoate, and the like. 
b. Mono-olefinically unsaturated acrylic or dicarboxylic acid esters such 
as the methyl, ethyl, propyl, isopropyl, butyl, t-butyl and iso-butyl 
esters, for example, alkylacrylates and methacrylates such as methyl 
acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl 
acrylate, n-amyl acrylate, isoamyl acrylate, n-hexyl acrylate, 
2-ethylhexyl acrylate, n-octyl acrylate, n-decyl acrylate, hydroxyethyl 
acrylate, hydroxypropyl acrylate, ethyl methacrylate, n-butyl 
methacrylate, cyanoethyl acrylate, cyanobutyl acrylate, diethylaminoethyl 
acrylate, esters of dicarboxylic acids such as monoisopropyl maleate, 
mono-2-ethylhexyl maleate, mono-n-butyl fumarate, dibutyl maleate, diethyl 
maleate and diethyl fumarate and the like. 
c. Amides of acrylic acid such as acrylamide, N-methyl acrylamide, N-phenyl 
acrylamide, N,N-dimethyl acrylamide, N,N-dibutylacrylamide and the like. 
d. Mono-olefinically unsaturated carboxylic acids, for example, acrylic 
acid, methacrylic acid, crotonic acid, cinnamic acid, alpha-chloroacrylic 
acid, atropic acid, alpha-fluoroacrylic acid, fumaric acid, maleic acid, 
itaconic acid and the like. 
e. Vinyl ethers such as vinyl isobutyl ether, vinyl decyl ether, and the 
like. 
These materials are selected so that the polymers made therefrom contain 
substantially intramolecular bonds and are substantially free of three 
dimensional cross-linking. 
The unsaturated polar organic compound may be present in the deactivating 
polymer in an amount from about 5 mole % to about 100 mole %, especially 
from about 10 mole % to about 50 mole % and preferably from about 25 mole 
% to about 45 mole % of the deactivating polymer the balance being the 
aforementioned olefin or olefins. The deactivating polymer may be either a 
random, block or graft polymer and is made according to methods that are 
well known in the polymerization art. In the process for deactivating the 
Ziegler-Natta or transition element oxide catalyst as described herein, 
the deactivating polymer is employed in an amount such that the molar 
ratio of the polar organic component of the deactivating polymer to the 
sum of the transition element component of the catalyst plus the 
co-catalyst is from about 0.1 to about 6 and preferably from about 2 to 
about 4. 
One of the preferred deactivating polymers comprises a copolymer of 
ethylene and vinyl acetate where the vinyl acetate is present in an amount 
from about 25% to about 60% on a weight basis and the balance ethylene.

The following examples are illustrative. 
EXAMPLES 1-10 
A bench scale reactor was used to evaluate an ethylene vinyl acetate (EVA) 
copolymer for the deactivation of a Ziegler-Natta catalyst. The reactor 
comprised a 3850 ml stainless steel autoclave equipped with a stirrer and 
a heating jacket. 
The catalyst employed comprised TMMG encapsulated catalyst prepared by 
adding 2.78 kg magnesium metal, 4.21 kg MgCl.sub.2.6H.sub.2 O and 54.42 kg 
titanium tetrabutylate to 54.42 kg octane. The temperature is increased to 
125.degree.-126.degree. C. while stirring and held at this temperature for 
4 hrs, after which the mixture is cooled to 38.degree. C. and set aside. A 
second batch of this mixture is prepared in the same way and combined with 
the first and with the temperature held at 10.degree. C.-13.degree. C., 
163.26 kg of silicon tetrachloride added and the mixture agitated for 8 
hrs. The stirring was stopped and the catalyst allowed to settle after 
which it was washed 6 times with 567.75 liters octane for each wash. After 
washing, 77.55 kg of 25% triethyl aluminum in octane solution was added 
followed by an addition of 14.51 kg of hexene-1. The mixture was then 
stirred for 2 hrs after which 321.73 liters of octane was added to 
complete the catalyst preparation. 
A random EVA copolymer containing 38.5 percent by weight of vinyl acetate 
and having a viscosity of 136 cp, measured at 140.degree. C. was prepared. 
In order to ensure that no unreacted vinyl acetate monomer was present, an 
octane solution of the above EVA copolymer (3.2 g EVA/40 ml of octane) was 
purged with nitrogen for one hour at 40.degree. C. prior to use. Ten 
polymerization reactions were conducted by charging the reactor with 1200 
ml isobutane, 117 psig ethylene, 190 ml butene-1, 55 psig hydrogen and the 
catalyst and in some instances the solution of EVA copolymer as described 
above. The reaction temperature was maintained substantially at 
76.7.degree. C., the pressure at 352 psig and the hydrogen pressure at 55 
psig while maintaining continuous agitation for the polymerization which 
was carried out over a 60 minute period. Additional butene-1, at a rate of 
7.6 ml/min, and ethylene, sufficient to maintain a constant pressure of 
352 psig, were added during the polymerization reaction. 
The reaction was conducted for a period of one hour in each example after 
which the contents of the reactor were dumped and analyzed. 
The results obtained are listed below in Table I. 
TABLE I 
__________________________________________________________________________ 
Catalyst EVA VA/ Productivity 
Powder Resin Properties 
Ex mg Ti 
mmol Ti 
Al/Ti 
(mmol VA) 
Al + Ti 
(g PE/g Ti-hr) 
MI MIR Density 
__________________________________________________________________________ 
1 1.5 0.0312 
13 -- -- Runaway -- -- -- 
2 0.75 
0.0156 
13 -- -- 909,335 1.68 
32.1 
0.9197 
3 0.45 
0.0094 
13 -- -- 1,104,445 
1.93 
31.1 
0.9200 
4 0.45 
0.0094 
13 0.132 1.0 413,335 1.08 
30.7 
0.9223 
5 0.45 
0.0094 
13 0.264 2.0 188,885 0.80 
28.0 
0.9234 
6 0.45 
0.0094 
13 0.330 2.5 -- -- -- -- 
7 0.45 
0.0094 
13 -- -- 771,110 1.39 
32.0 
0.9205 
8 1.5 0.0312 
13 1.082 2.5 -- -- -- -- 
9 0.45 
0.0094 
13 -- -- 271,110 1.00 
31.9 
0.9188 
10 0.45 
0.0094 
13 -- -- 762,220 1.24 
32.9 
0.9138 
__________________________________________________________________________ 
The aluminum reported in Table I above is based on aluminum as triethyl 
aluminum. 
(1) mole ratio of vinyl acetate (VA) from EVA copolymer to Al + Ti of 
catalyst. 
The above data indicate that the addition of an EVA copolymer resulted in a 
decrease in catalyst activity. Further increases produced total 
deactivation at 2.5:1 VA:Al+Ti. This ratio also prevented polymerization 
at Al and Ti levels which normally would result in runaway polymerization. 
Comparisons of melt index and density for runs with and without EVA show 
that EVA reduces both hydrogen sensitivity and butene incorporation. 
EXAMPLES 11-16 
The method of Examples 1-10 was employed using a prepolymerized hexene-1 
titanium compound catalyst with triethyl aluminum as a co-catalyst in the 
evaluation of EVA copolymers as catalyst deactivators. The catalyst was 
prepared in the same manner as described for Examples 1-10. 
The same apparatus and procedure as used in Examples 1-10 were employed; 
however, the polymerization temperature employed was 87.8.degree. C. The 
results obtained are tabulated below in Table II. 
TABLE II 
__________________________________________________________________________ 
Al/Ti 
EVA VA/ Productivity 
Polymer 
Ex 
mg Ti 
mmol Ti 
(molar) 
(mmol VA) 
Al + Ti 
g PE/g Ti/hr 
Density 
__________________________________________________________________________ 
11 
1.5 0.0312 
13 -- -- runaway reaction 
-- 
12 
0.45 
0.0094 
13 -- -- 1,104,445 
0.9200 
13 
0.45 
0.0094 
13 0.132 1.0 413,335 
0.9223 
14 
0.45 
0.0094 
13 0.264 2.0 188,885 
0.9234 
15 
0.45 
0.0094 
13 0.330 2.5 no reaction 
-- 
16 
1.5 0.0312 
13 1.082 2.5 no reaction 
-- 
__________________________________________________________________________ 
From the above data it is apparent that the activity of the catalyst for 
polymerization is reduced with increasing concentrations of EVA copolymer 
in the reactor. When the EVA concentration was such that the molar ratio 
of vinyl acetate in the copolymer to the sum of aluminum (from triethyl 
aluminum) and titanium in the catalyst was 2.5/1, the catalyst was 
deactivated as indicated by "no reaction." At lesser ratios, the activity 
of the catalyst was reduced. 
Although the invention has been described by reference to some embodiments, 
it is not intended that the novel method for deactivating olefin 
polymerization catalysts are to be limited thereby but that modifications 
thereof are intended to be included as falling withing the spirit and 
broad scope of the foregoing disclosure and the following claims.