Termination of gas phase polymerizations of conjugated dienes, vinyl-substituted aromatic compounds and mixtures thereof

There is provided a method for terminating a gas phase polymerization of a compound selected from the group consisting of a conjugated diene, a vinyl-substituted aromatic compound, and mixtures thereof, in a polymerization vessel in the presence of a catalyst, and optionally in the presence of an inert particulate material, comprising introducing a kill agent selected from the group consisting of an alcohol having 1 to 20 carbon atoms, an alkyl or cycloalkyl monoether, ammonia, water, an alkyl or aryl amine, and mixtures thereof.

FIELD OF THE INVENTION 
The present invention relates to a method for terminating gas phase 
polymerizations of conjugated dienes, vinyl-substituted aromatic 
compounds, and mixtures. More particularly, the invention relates to the 
termination of such processes using a kill agent selected from the group 
consisting of an alcohol having 1 to 20 carbon atoms, a alkyl or 
cycloalkyl monoether having 2 to 20 carbon atoms, ammonia, water, an alkyl 
or aryl amine, and mixtures thereof. 
BACKGROUND OF THE INVENTION 
It has recently been discovered that polybutadiene, polyisoprene, 
polystyrene, and styrene-butadiene polymers can be polymerized in a 
fluidized gas phase reactor in the presence of a transition metal catalyst 
(including metallocenes) and/or a rare earth metal catalyst. 
Accordingly, there is a need for an effective process for completely or 
practically completely stopping such polymerizations. It has further been 
found that deactivating agents or kill agents useful in alpha olefin 
polymerizations (e.g., CO, CO.sub.2, and the like) are not effective to 
terminate polymerizations employing butadiene, isoprene, styrene, and 
mixtures of them. 
Surprisingly, it has been discovered that the process of the present 
invention enables a gas phase polymerization of, for example, butadiene, 
isoprene, styrene, or styrene and butadiene to be stopped without being 
obliged to remove the reaction gas mixture from the polymerization reactor 
system. However, before restarting the polymerization reaction, the 
reaction mixture may have to be purged in order to remove from the reactor 
any remaining kill agent. Also, the process according to the present 
invention allows the polymerization reaction to be restarted without 
draining the bed, simply by feeding the reactor again with fresh diene 
monomer and optionally catalyst, cocatalyst, and/or promoter. 
SUMMARY OF THE INVENTION 
Accordingly, the present invention provides a process for terminating a 
polymerization of a compound selected from the group consisting of a 
conjugated diene, a vinyl-substituted aromatic compound, and mixtures 
thereof comprising introducing a kill agent selected from the group 
consisting of an alcohol having 1 to 20 carbon atoms, an alkyl or 
cycloalkyl monoether having 2 to 20 carbon atoms, ammonia, water, an alkyl 
or aryl amine, and mixtures thereof in an amount effect to terminate the 
polymerization. 
Detailed Description of the Invention 
Polymers. The process of the invention is suited for stopping a gas phase 
polymerization reaction of one or more dienes and/or one or more 
vinyl-substituted aromatic compounds. Illustrative of the polymers which 
can be produced in accordance with the invention are the following: 
polyisoprene; polybutadiene; polystyrene, butadiene copolymerized with 
styrene; a polymer of acrylonitrile, butadiene, and styrene; a polymer of 
butadiene and acrylonitrile; a polymer of isobutylene and isoprene; 
polychloroprene; and a copolymer of ethylene and one or more of 
acrylonitrile, butadiene, isoprene, styrene, chloroprene, and/or 
isobutylene. Typically, these polymers range in Mooney from 20 to 100, 
have a cis-content ranging from 40 to 100 percent, and have low gels. The 
polymers produced by the gas phase process described in the present 
invention are granular and free-flowing and find utility in automotive 
applications such as weather stripping, hoses, tire components, and 
ignition cables. They can also be used in wire and cable, construction in 
materials such as roofing products, hose and tubing, and mechanical 
applications. 
Polymerization. The polymerization can be in solution/slurry, fluidized, 
stirred, bulk, high pressure, low pressure, or half slurry/half gas phase. 
For the polymerization process of the invention, the fluidized bed can be 
a stirred fluidized bed reactor or a fluidized bed reactor which is not 
stirred. Preferably, the polymerization is conducted in at least one gas 
phase reactor. When multiple reactors are employed, it is preferred that 
they be used in series. The present invention is not limited to any 
specific type of gas phase polymerization reaction. In addition to 
conventional gas phase polymerization processes, "condensed mode" 
including the so-called "induced condensed mode" and "liquid monomer" 
operation of a gas phase polymerization can be employed. 
A conventional fluidized bed process for producing resins, such as 
disclosed in U.S. Pat. Nos. 4,482,687; 4,994,534; 5,304,588; and EP 0 
647,657A1 is practiced by passing a gaseous stream containing one or more 
monomers continuously through a fluidized bed reactor under reactive 
conditions in the presence of a polymerization catalyst. Product is 
withdrawn from the reactor. A gaseous stream of unreacted monomer is 
withdrawn from the reactor continuously and recycled into the reactor 
alone with make-up monomer added to the recycle stream. 
Condensed mode polymerizations are disclosed in U.S. Pat. Nos. 4,543,399; 
4,588,790; 4,994,534; 5,317,036; 5,352,749; and 5,462,999. Condensing mode 
processes are employed to achieve higher cooling capacities and, hence, 
higher reactor productivity. In these polymerizations a recycle stream, or 
a portion thereof, can be cooled to a temperature below the dew point in a 
fluidized bed polymerization process, resulting in condensing all or a 
portion of the recycle stream. The recycle stream is returned to the 
reactor. The dew point of the recycle stream can be increased by 
increasing the operating pressure of the reaction/recycle system and/or 
increasing the percentage of condensable fluids and decreasing the 
percentage of non-condensable gases in the recycle stream. The condensable 
fluid may be inert to the catalyst, reactants and the polymer product 
produced; it may also include monomers and comonomers. The condensing 
fluid can be introduced into the reaction/recycle system at any point in 
the system. Condensable fluids include saturated or unsaturated 
hydrocarbons. In addition condensable fluids of the polymerization process 
itself other condensable fluids, inert to the polymerization can be 
introduced to "induce" condensing mode operation. Examples of suitable 
condensable fluids may be selected from liquid saturated hydrocarbons 
containing 2 to 8 carbon atoms (e.g., propane, n-butane, isobutane, 
n-pentane, isopentane, neopentane, n-hexane, isohexane, and other 
saturated C.sub.6 hydrocarbons, n-heptane, n-octane and other saturated 
C.sub.7 and C.sub.8 hydrocarbons, and mixtures thereof). Condensable 
fluids may also include polymerizable condensable comonomers such as 
olefins, alpha-olefins, diolefins, diolefins containing at least one alpha 
olefin, and mixtures thereof. In condensing mode, it desirable that the 
liquid entering the fluidized bed be dispersed and vaporized quickly. 
Liquid monomer polymerization mode is disclosed, in U.S. Pat. No. 
5,453,471; U.S. Ser, No. 510,375 now pending; PCT 95/0986 (US) and PCT 
95/09827 (US). When operating in the liquid monomer mode, liquid can be 
present throughout the entire polymer bed provided that the liquid monomer 
present in the bed is adsorbed on or absorbed in solid particulate matter 
present in the bed, such as polymer being produced or fluidization aids 
(e.g., carbon black) present in the bed, so long as there is no 
substantial amount of free liquid monomer present more than a short 
distance above the point of entry into the polymerization zone. Liquid 
mode makes it possible to produce polymers in a gas phase reactor using 
monomers having condensation temperatures much higher than the 
temperatures at which conventional polyolefins are produced. In general, 
liquid monomer process are conducted in a stirred bed or gas fluidized bed 
reaction vessel having a polymerization zone containing a bed of growing 
polymer particles. The process comprises continuously introducing a stream 
of one or more monomers and optionally one or more inert gases or liquids 
into the polymerization zone; continuously or intermittently introducing a 
polymerization catalyst into the polymerization zone; continuously or 
intermittently withdrawing polymer product from the polymerization zone; 
and continuously withdrawing unreacted gases from the zone; compressing 
and cooling the gases while maintaining the temperature within the zone 
below the dew point of at least one monomer present in the zone. If there 
is only one monomer present in the gas-liquid stream, there is also 
present at least one inert gas. Typically, the temperature within the zone 
and the velocity of gases passing through the zone are such that 
essentially no liquid is present in the polymerization zone that is not 
adsorbed on or absorbed in solid particulate matter. In the present 
invention, liquid monomer gas phase polymerization is preferred. 
The process can be carried out in a batch, intermittent, or continuous 
mode, the latter being preferred. The essential parts of the reactor are 
the vessel, the bed, the gas distribution plate, inlet and outlet piping, 
a compressor, a cycle gas cooler, and a product discharge system. In the 
vessel, above the bed, there is a velocity reduction zone, and in the bed, 
a reaction zone. Both are above the gas distribution plate. 
Polybutadiene, polyisoprene, and styrene homo- and co-polymers can be 
produced in the gas phase by use of a transition metal catalyst, including 
metallocenes, rare earth metal catalyst, or mixtures of them. Such 
catalysts can be supported or unsupported, in solution and/or slurry, 
spray dried, or in prepolymer form. However, in this invention, 
polybutadiene, polyisoprene, and styrene homo- and co-polymers are 
preferably produced in accordance with the processes and procedures 
disclosed in WO 96/04323 (PCT/US95/09827) in the presence of a rare earth 
metal catalyst. Alternatively, these polymers can be produced using the 
procedures disclosed in WO 96/04322 (PCT/US95/09826) in the presence of a 
transition metal catalyst (including nickel, cobalt, titanium, and/or a 
metallocene component). The butadiene (e.g., 1,3-butadiene), isoprene, or 
styrene is introduced directly into the polymerization zone of the reactor 
or carried into the polymerization zone as with the recycle gas stream or 
a combination of both. The temperature within the polymerization zone can 
be maintained below the condensation temperature of the diene monomer in 
the zone. Or, in another embodiment, the conditions (e.g., temperature, 
pressure, concentration of diene monomer) within the polymerization zone 
are such that essentially no liquid is present in the zone that is not 
adsorbed on or absorbed in solid particulate matter. Alternatively, the 
conditions with the polymerization zone are maintained such that a portion 
of the diene monomer is a liquid that is not adsorbed on or absorbed in 
the solid particulate matter. 
The rare earth metal catalyst employed in the polymerization zone is not 
limited to any particular class of rare earth metal catalyst. Rare earth 
catalysts that have been previously employed in slurry, solution, or bulk 
polymerizations of higher boiling or readily condensable monomers (e.g., 
butadiene and isoprene) can be utilized in this invention. The rare earth 
metal catalysts employed in the invention can have a rare earth metal 
precursor component, a co-catalyst component, and optionally a promoter. 
The precursor component can be a single compound or a mixture of two or 
more rare earth metal compounds. The precursor component can be introduced 
to the polymerization zone in a solution or slurry, on a support (e.g., 
silica, carbon black, porous crosslinked polystyrene or polypropylene, 
alumina, or magnesium chloride), spray dried, or as a prepolymer. 
Any compound, organic or inorganic, of a metal chosen from those of Group 
IIIB of the Periodic Table of the Elements having an atomic number of 
between 57 and 103 can be employed herein. Examples of rare earth metal 
compounds are compounds of cerium, lanthanum, praseodymium, gadolinium and 
neodymium. Of these compounds, carboxylates, alcoholates, 
acetylacetonates, halides (including ether and alcohol complexes of 
neodymium trichloride), and allyl derivatives of the metals are preferred. 
Neodymium compounds are the most preferred. Illustrative neodymium 
compounds can include neodymium naphthenate, neodymium octanoate, 
neodymium octoate, neodymium trichloride, neodymium trichloride complexes 
formed with tetrahydrofuran (e.g., NdCl.sub.3 (THF).sub.2) and ethanol 
(e.g., (NdCl.sub.3 (EtOH).sub.3), neodymium 2,2-diethylhexanoate, 
neodymium 2-ethylhexoate, neodymium 2-ethyloctoate, neodymium 2,2-diethyl 
heptanoate, allyl neodymium dichloride, bis-allyl neodymium chloride, and 
tris-allyl neodymium. Neodymium neodecanoate, neodymium octanoate, 
neodymium versatare, and p-allyl neodymium dichloride give particularly 
good results. A mixture of rare earth metal catalysts can be employed. 
And, one or more rare earth metal catalysts can also be used in 
combination with at least one transition metal catalyst (including a 
metallocene catalyst) in a single reactor or in multiple reactors, 
preferably connected in series. 
In general, the rare earth compounds, particularly the neodymium compounds 
used to prepare the rare earth catalysts described herein, can be obtained 
as solutions or suspensions in known diluents (aliphatic, aromatic, 
oxygenated hydrocarbons) containing no or small amounts of water (0.001 to 
5%) and/or with an excess of rigand (0.001 to 10 equivalents). Other 
reagents such as alcohols, carboxylic acids, amines, amides or ethers can 
be added to solutions or suspensions to maintain the solubility of the 
rare earth compound. Preferably, the hydrocarbon solutions or suspensions 
of the rare earth compound (e.g. neodymium compound) will contain 0 to 
2500 ppm water and 0.5 to 2 equivalents of free rigand such as, for 
example, versatic acid. The neodymium compound is typically used as a 1 to 
50 wt % solution. These solutions or suspensions, such as, for example, 
neodymium versatate in hexane (8.9% Nd; 9.3% versatic acid; 150 ppm water, 
Lot #9534101) used in some of the examples herein can be obtained from 
Rhone-Poulenc. 
A single site catalyst is another preferred catalyst which can be employed 
alone or in combination with a rare earth metal catalyst and/or transition 
metal catalyst to make polymers of this invention. One such catalyst is 
disclosed in U.S. Pat. No. 5,527,752 to Reichle et al. This catalyst 
comprises complexes of transition metals, substituted or unsubstituted 
p-bonded ligands and heteroallyl moieties, useful as catalyst precursors 
in polyolefin polymerizations typically in conjunction with a cocatalyst 
such as MAO or MMAO. 
Rare earth catalyst modifiers and co-catalysts consist of aluminum alkyl 
halides and trialkyl alumimum compounds as described in WO 96/04323. 
Preferred co-catalysts that can be employed with the rare earth metal 
precursor component include triethylaluminum (TEAL), triisobutylaluminum 
(TIBA), trihexylaluminunm (THAL), methylaluminoxane (MAO), modified 
methylalnminoxane (MMAO), trimethylaluminum (TMA), a dialkyl aluminum 
hydride or a mixture of a dialkyl aluminum hydride or a mixture of a 
dialkyl aluminum hydride and a trialkyl aluminum. When employed, promoters 
that can be used with rare earth metal compounds include one or more Lewis 
acids such as BCl3, AlCl3, ethylaluminum dichloride, ethylaluminum 
sesquichloride, diethylaluminum chloride, and other alkyl radical 
derivatives. Also, organohalide derivatiives of these compounds such as 
those ennmerated in WO 96/04323 can be employed. 
The conventional Ziegler-Natta catalysts, by which is meant those formed by 
reacting a metal alkyl or hydride with a transition metal compound, are 
preferred in the practice of this invention. Those formed by reacting an 
aluminum alkyl with salts of metals of Groups I to III of the Periodic 
Table of the Elements are particularly useful. 
Illustrative of the catalysts useful in the practice of this invention are 
the following: 
A. Titanium based catalysts such as those described in U.S. Pat. Nos. 
4,376,062; 4,379,758. 
B. Chromium based catalysts such as those described in U.S. Pat. Nos. 
3,709,853; 3,709,954; and 4,077,904. 
C. Vanadium based catalysts such as vanadium oxychloride and vanadium 
acetylacetonate. 
D. Metallocene catalysts such as those described in U.S. Pat. Nos. 
4,530,914; 4,665,047; 4,752,597; 5,218,071; 5,272,236; 5,278,272; 
5,317,036; and 5,527,752. 
E. Cationic forms of metal halides. 
F. Cobalt catalysts and mixture thereof such as those described in U.S. 
Pat. Nos. 4,472,559 and 4,182,814. 
G. Nickel catalysts and mixtures thereof such as those described in U.S. 
Pat. Nos. 4,155,880, 4,102,817, PCT 95/09826(US) and PCT 95/09827(US). 
The transition metal catalysts employed in the process of this invention 
can have a metal component, a co-catalyst, and optionally a promoter. The 
metal component can be a transition metal compound or a mixture of two or 
more transition metal compounds. In general, the transition metal 
component of the catalyst can be soluble or insoluble, supported or 
unsupported, or spray dried in either the presence or absence of a filler. 
Alternatively, the polymerization catalyst can be introduced to the 
polymerization zone in the form of a prepolymer using techniques known to 
those skilled in the art or as described for EPRs and EPDMs. 
When the metal component is supported, typical supports can include, for 
example, silica, carbon black, porous crosslinked polystyrene, porous 
crosslinked polypropylene, alumina, thoria, zirconia, magnesium halide 
(e.g., magnesium chloride) support materials, and their mixtures. Silica, 
carbon black, and alumina are preferred support materials. Silica, carbon 
black, and mixtures of them are the most preferred support materials. A 
typical silica or alumina support is a solid, particulate, porous material 
essentially inert to the polymerization. It is used as a dry powder having 
an average particle size of about 10 to about 250 microns and preferably 
about 30 to about 100 microns; a surface area of at least 200 square 
meters per gram and preferably at least about 250 square meters per gram; 
and a pore size of at least about 100 Angstroms and preferably at least 
about 200 Angstroms. Generally, the amount of support used is that which 
will provide about 0.1 to about 1.0 millimole of transition metal per gram 
of support. In a preferred embodiment, two types of carbon black are used 
as support. DARCO G-60 (pH of water extract=5) is used as dry powder 
having a surface area of 505 square meters per gram, average particle size 
of 100 microns, and porosity of 1.0 to 1.5 cubic centimeter per gram. 
NORIT A (pH of water extract=9-11) used as a dry powder has a surface area 
of 72 0 square meters per gram, average particle size of 45 to 80 microns. 
The metal component can be impregnated on a support by well known means 
such as by dissolving the metal compound in a solvent or diluent such as a 
hydrocarbon or tetrahydrofuran in the presence of the support material and 
then removing the solvent or diluent by evaporation such as under reduced 
pressure. Alternatively, the transition metal component can be dissolved 
in a solvent or diluent such as a hydrocarbon or tetrahydrofuran and spray 
dried to generate a well-shaped catalyst precursor having little or no 
silica or other inorganic solids content, if desired. 
The preferred transition metal compounds for making the polymers (e.g., 
polybutadiene, polyisoprene, polystyrene, and styrene-butadiene rubber) 
are compounds containing nickel, titanium, and cobalt, with cobalt and 
nickel compounds being the most preferred. Nickel compounds of the metal 
component of the catalyst are organonickel compounds of nickel with mono- 
or bidentate organic ligands containing up to 20 carbon atoms. "Ligand" is 
defined as an ion or molecule bound to and considered bonded to a metal 
atom or ion. Mono-dentate means having one position through which covalent 
or coordinate bonds with the metal may be formed; bidentate means having 
two positions through which covalent or coordinate bonds with the metal 
may be formed. The organonickel compounds are generally soluble in inert 
solvents. Thus, any salt or an organic acid containing from about 1 to 20 
carbon atoms may be employed. Representative of organonickel compounds are 
nickel benzoate, nickel acetate, nickel naphthenate, nickel octanoate, 
nickel neodecanoate, nickel 2-ethylhexanoate, bis(-.pi.-allyl nickel), 
bis(cycloocta-1,5-diene), bis(allyl nickel trifluoroacetate), bis(furyl 
dioxime) nickel, nickel palmitate, nickel stearate, nickel 
acetylacetonate, nickel salicaldehyde, bis(salicyladehyde) ethylene 
diimine nickel, bis(cyclopentadiene) nickel, cyclopentadienylnickel 
nitrosyl and nickel tetracarbonyl. The preferred component containing 
nickel is a nickel salt of a carboxylic acid or an organic complex 
compound of nickel. 
Co-catalysts that can be employed with the component containing nickel 
include triethylaluminum (TEAL), triisobutylaluminum (TIBA), diethyl 
aluminum chloride (DEAC), partially hydrolyzed diethyl aluminum chloride 
(DEACO), methylaluminoxane (MAO), or modified methylaluminoxane (MMAO). 
When MAO or MMAO is employed as the co-catalyst, it may be one of the 
following: (a) branched or cyclic oligomeric poly(hydrocarbylaluminum 
oxide)s which contain repeating units of the general formula 
--(Al(R'")O)--, where R'" is hydrogen, an alkyl radical containing from 1 
to about 12 carbon atoms, or an aryl radical such as a substituted or 
unsubstituted phenyl or naphthyl group; (b) ionic salts of the general 
formula A!.sup.+1 BR*.sub.4 !.sup.-1 , where A+ is a cationic Lewis or 
Bronsted acid capable of abstracting an alkyl, halogen, or hydrogen from 
the transition metal component of the catalyst, B is boron, and R* is a 
substituted aromatic hydrocarbon, preferably a perfluorophenyl radical; 
and (c) boron alkyls of the general formula BR*.sub.3, where R* is as 
defined above. 
Aluminoxanes are well known in the art and comprise oligomeric linear alkyl 
aluminoxanes represented by the formula: 
##STR1## 
and oligomeric cyclic alkyl aluminoxanes of the formula: 
##STR2## 
wherein s is 1 to 40, preferably 10 to 20; p is 3 to 40, preferably 3 to 
20; and R'" is an alkyl group containing 1 to 12 carbon atoms, preferably 
methyl or an aryl radical such as a substituted or unsubstituted phenyl or 
naphthyl radical. Modified methylaluminoxane is formed by substituting 
20-80 wt % of the methyl groups with a C.sub.2 to C.sub.12 group, 
preferably with isobutyl groups, using techniques known to those skilled 
in the art. 
Promoters that can be used with the component containing nickel include 
hydrogen fluoride (HF), borontrifluoride (BF.sub.3), or an etherate of HF 
and/or BF.sub.3. 
The titanium compound (titanares) can be TICl.sub.4, TiBr.sub.4, TiI.sub.4 
or Ti(OR).sub.4 wherein R is an alkyl radical. 
Co-catalysts that can be employed with the component containing titanium 
include TEAL, TIBA, dialkylaluminum iodide, and MAO. 
Promoters that can be used with the component containing titanium include 
iodine and organic etherares. For isoprene, the combination TICl.sub.4, 
TIBA, and DPE (diphenyl ether) is employed. 
The cobalt compound can be any organic compound such as the cobalt salts of 
organic acids, cobalt complexes and the like. Preferably, the cobalt 
compound is selected from the group consisting of cobalt .beta.-ketone 
complexes, for example, cobalt (II) acetylacetonate and cobalt (III) 
acetylacetonate; cobalt .beta.-ketoacid ester complexes, for example, 
cobalt acetylacetonate ethylester complexes; cobalt salts of organic 
carboxylic acids having 6 or more carbon atoms, for example, cobalt 
octoate, cobalt naphthenate, and cobalt benzoate; and cobalt halide 
complexes, for example, cobalt chloride-pyridine complexes; 
cobalt-chloride-phosphine complexes; cobalt-chloride-ethyl alcohol 
complexes and cobalt complexes coordinated with butadiene, for example, 
(1,3-butadiene) 1-(2-methyl-3-butenyl)-.pi.-allyl!-cobalt which may be 
prepared, for example, by mixing a cobalt compound with an organic 
aluminum compound, organic lithium compound or alkyl magnesium compound 
and 1,3-butadiene. Other typical cobalt compounds are cobalt sorbate, 
cobalt adipate, cobalt 2-ethylhexoate, cobalt stearate, and the like 
compounds wherein the organic portion of the molecule contains about 5 to 
20, preferably 8 to 18 carbon atoms and one or two carboxylic functions, 
as well as acetylacetonate. 
Co-catalysts that can be employed with the component containing cobalt 
include ethylaluminum sesquichloride (EASC), ethylaluminum dichloride 
(EADC), DEACO, MAO and mixtures thereof. 
Water in small amounts can be used as a promoter with the metal component 
containing cobalt, if desired. 
Inert Particulate Material. Fluidization aids employed in the 
polymerization processes can be inert particulate materials which are 
chemically inert to the reaction. Examples of such fiuidization aids or 
flow aids include carbon black, silica, clays and other like materials 
such as talc. Organic polymeric materials can also be employed as a 
fiuidization aid. Carbon blacks and silicas and their mixture are the 
preferred fiuidization aids with carbon black being the most preferred. 
The carbon black materials employed have a primary particle size of about 
10 to 100 nanometers and an average size of aggregate (primary structure) 
of about 0.1 to about 10 microns. The specific surface area of the carbon 
black is about 30 to 1,500 m.sup.2 /gm and the carbon black displays a 
dibutylphthalate (DBP) absorption of about 80 to about 350 cc/100 grams. 
Silicas which can be employed are amorphous and have a primary particle 
size of about 5 to 50 nanometers and an average size of aggregate about 
0.1 to 10 microns. The average size of agglomerates of silica is about 2 
to about 120 microns. The silicas employed have a specific surface area of 
about 10 to 500 m.sup.2 /gm and a dibutylphthalate (DBP) absorption of 
about 100 to 400 cc/100 grams. 
Clays and talc which can be employed according to the invention have an 
average particle size of about 0.01 to about 10 microns and a specific 
surface area of about 3 to 30 m.sup.2 /gm. They exhibit oil absorption of 
about 20 to about 100 gms per 100 gms. 
Organic polymeric substances which can be used include polymers and 
copolymers of ethylene, propylene, butene, and other alpha olefins and 
polystyrene, in granular or powder form. These organic polymeric materials 
have an average particle size ranging from about 0.01 to 100 microns, 
preferably 0.01 to 10 microns. 
In general, the mount of fiuidization aid utilized generally depends on the 
type of material utilized and the type of polybutadiene or polyisoprene 
produced. When utilizing carbon black or silica as the fiuidization aid, 
they can be employed in amounts of about 0.3% to about 80% by weight, 
preferably about 5% to about 60%, and most preferably about 10% to about 
45%, based on the weight of the final product (polybutadiene or 
polysioprene or styrene polymer) produced. When clays or talcs are 
employed as the fiuidization aid, the amount can range from about 0.3% to 
about 80% based on the weight of the final product, preferably about 12% 
to 75% by weight. Organic polymeric materials are used in mounts of about 
0.1% to about 50% by weight, preferably about 0.1% to about 10% based on 
the weight of the final polymer product produced. 
The fluidization aid can be introduced into the reactor at or near the top 
of the reactor, at the bottom of the reactor, or to the recycle line 
directed into the bottom of the reactor. Preferably, the fiuidization aid 
is introduced at or near the top of the reactor or above the fluidized 
bed. It is preferred to treat the fiuidization aid prior to entry into the 
reactor to remove traces of moisture and oxygen. This can be accomplished 
by purging the material with nitrogen gas and heating by conventional 
procedures. The fluidization aid can be added separately or combined with 
one or more butadiene monomers, or with a soluble unsupported catalyst. 
Preferably, the fluidization aid is added separately. 
Other Additives. Conventional techniques for the prevention of fouling of 
the reactor and polymer agglomeration can be used in the practice of our 
invention. Illustrative of these techniques are addition of negative 
charge generating chemicals to balance positive charge generating 
chemicals or by addition of positive charge generating chemicals to 
neutralize negative Voltage potentials as described in U.S. Pat. No. 
4,803,251. Antistat substances may also be added continuously or 
intermittently directly to the reactor or into the recycle lines to 
prevent or neutralize static charge generation. Other additive which can 
be employed include chain transfer agents, scavenging agents, and the 
like. 
Preferably, the polymerizations of the invention are carried out in the gas 
phase, preferably in a fluidized bed made up of, or containing a "seed 
bed" of polymer such as particulate polybutadiene, polyisoprene, 
polystyrene, styrene-butadiene rubber, or mixtures thereof. The bed is 
usually made up of the same granular resin that is to be produced in the 
reactor. Accordingly, using a seed bed of starting material (particulate 
polymer) which is the same or substantially the same as the polymer to be 
produced is preferred. Typically, a seed bed (having a moisture content of 
20 to 600 ppm) from a previous run, optionally also containing inert 
particulate material (fiuidization aid), is employed. This bed is can be 
dried to 300 to 400 ppm or less and optionally passivated with an aluminum 
alkyl (e.g., co-catalyst) before commencing a polymerization. Thus, during 
the course of the polymerization, the bed comprises formed polymer 
particles, growing polymer particles, and catalyst particles fluidized by 
polymerizing and modifying gaseous components introduced at a flow rate or 
velocity sufficient to cause the particles to separate and act as a fluid. 
The fluidizing gas is made up of the initial feed, make-up feed, and cycle 
(recycle) gas, i.e., one or more dienes or vinyl-substituted aromatic 
compounds and, optionally, other monomers (e.g., alpha olefins having 2-18 
carbon atoms) and, if desired, modifiers and/or an inert carrier gas 
(nitrogen, argon, hydrocarbons, e.g. ethane). A typical cycle gas is 
comprised of one or more dienes optional monomers when present, nitrogen, 
and hydrogen, either alone or in combination. The process can be carried 
out in a batch or continuous mode, the latter being preferred. The 
essential parts of the reactor are the vessel, the bed, the gas 
distribution plate, inlet and outlet piping, a compressor, a cycle gas 
cooler, and a product discharge system. In the vessel, above the bed, 
there is a velocity reduction zone, and in the bed, a reaction zone. Both 
are above the gas distribution plate. 
Variations in the reactor can be introduced if desired. One involves the 
relocation of one or more cycle gas compressors from upstream to 
downstream of the cooler and another involves the addition of a vent line 
from the top of the product discharge vessel (stirred product tank) back 
to the top of the reactor to improve the fill level of the product 
discharge vessel. 
In terms of the fluidized bed, a superficial gas velocity of about 1 to 
about 4.5 feet per second and preferably about 1.5 to about 3.5 feet per 
second can be used. The total reactor pressure can be in the range of 
about 150 to about 600 psia and is preferably in the range of about 250 to 
about 500 psia. The diene or vinyl-substituted aromatic compound partial 
pressure can be in the range of about 25 psi to about 350 psi and is 
preferably in the range of about 60 psi to about 250 psi. The 
polymerizations of the invention are performed above the softening 
temperature of the polymer being produced, i.e., about 20.degree. C. to 
about 70.degree. C. Feed streams of liquid diene and/or aromatic compound 
and hydrogen (or other chain transfer agent) are preferably fed to the 
reactor recycle line or directly to the fluidized bed reactor, or both, to 
enhance mixing and dispersion. The composition of polymer product can be 
varied by changing the diene and/or vinyl-substituted aromatic compound 
molar ratio in the gas phase and the diene/aromatic compound concentration 
in the fluidized bed. The product is intermittently discharged from the 
reactor as the bed level builds up with polymer. The production rate is 
controlled by adjusting the catalyst feed rate. 
Kill Agent. A kill agent selected from the group consisting of an alcohol 
having 1 to 20 carbon atoms, an alkyl or cycloalkyl monoether having 2 to 
20 carbon atoms, ammonia, water, an alkyl or aryl amine, and mixtures 
thereof in an amount effect to terminate the polymerization is introduced 
to the reactor to terminate the polymerization. When employed, the alkyl 
amine can be a mono-, di- or tri-substituted amine in which each alkyl 
group can independently have 1 to 20 carbon atoms, preferably 1 to 10 
carbon atoms, most preferably 1 to 4 carbon atoms. The aryl amine used can 
have 6 to 24 carbon atoms, preferably 6 to 14 carbon atoms. Preferred 
amines are butyl amine and aniline. Preferably, the kill agent is selected 
from the group consisting of tetrahydrofuran, ammonia, water, methanol, 
ethanol, and mixtures thereof. Of these, gaseous ammonia is most 
preferred. In any event, it is preferred to use a kill agent which will 
allow the polymerization to be restarted. The kill agent can be added 
directly to the reactor, preferably into a reactor zone where the 
dispersion of the agent is fast, for example, under the fiuidization grid. 
It can be added into the recycle lines downstream of one or more 
compressors, preferably at a point situated as close as possible to the 
return to the polymerization reactor, or added in one or more of the 
monomer streams. 
The kill agent is introduced into the reactor over a relatively short 
period of time, typically less than 5 minutes. The period of introduction 
of the kill agent is advantageously as short as possible and is preferably 
shorter than one minute and more preferably shorter than 30 seconds. 
Furthermore, it is also desirable to discontinue the feeding of monomer 
(e.g., butadiene, isoprene, and or styrene) to the polymerization reactor. 
Under these conditions, a stoppage of the polymerization reaction is 
observed quickly, generally in less than 10 minutes and in many cases in 
less than 5 minutes after the end of the introduction of the kill agent 
into the polymerization reactor. 
The kill agent is introduced into the polymerization reactor in a quantity 
which is sufficient to substantially terminate the polymerization or to 
deactivate substantially all the catalyst present in the polymerization 
reactor and thus to stop the polymerization reaction. In practice, the 
quantity of agent introduced in the reactor is from i to 10 times and 
preferably from I to 3 times the minimum quantity necessary for stopping 
the polymerization. This minimum quantity can be obtained by previous 
experimentation performed in a reactor working with known quantities of 
catalyst and kill agent. For this purpose the agent is preferably 
introduced into the polymerization reactor in a quantity such that in the 
reactor the mole ratio of kill agent to cocatalyst is at least 0.05 to 
5:1. The use of a quantity of kill agent which is too small would have 
little or no effect on the catalyst and it would be difficult to observe a 
stoppage of the polymerization reaction. There is no upper limit of the 
quantity of agent to be used. However, the quantity of kill agent is often 
such that in the reactor the mole ratio of kill agent to cocatalyst is 0.1 
to 2:1, most preferably 0.5 to 1 (kill agent):l(cocatalyst). The 
polymerizations can be restarted by the adding more diene and/or 
vinyl-substituted aromatic compound, catalyst and/or cocatalyst, or adding 
all of these components to the reactor. Generally, in order to restart the 
polymerization, it is only necessary to add additional cocatalyst. 
All patents mentioned in this application are hereby incorporated by 
reference.

EXAMPLES 
The following examples are provided to illustrate the invention. 
Catalyst Systems: The catalysts are fed to the gas phase reactor either in 
solution or supported on silica or carbon black. The catalysts can be 
activated before or after addition or can be added as pre polymerized 
catalysts as well. The following catalysts and cocatalysts were used in 
the reaction termination experiments: 
A. Silica supported neodymium neodecanoate (Nd(neodec).sub.3) treated with 
1.5 equivalents of diethyl aluminum chloride (DEAC): Nd(neodec).sub.3 -1.5 
DEAC/SiO2, with tri-iso-butyl aluminum (TIBA) or di-iso-butyl aluminum 
hydride (DIBAH) as cocatalysts. 
B. Silica supported neodymium versarate (Nd(ver).sub.3) treated with 4.5 
equivalents of diethyl aluminum chloride (DEAC): Nd(Neodec).sub.3 -4.5 
DEAC/SiO2, with TIBA or DIBAH as cocatalysts. 
C. Toluene solution bis - allyl - neodymium chloride - methyl aluminoxane 
complex: bis-p-allyl-NdCl/MAO. 
D. Silica supported cobalt octoate: Co(oct).sub.2 /SiO.sub.2, in 
conjunction with partially hydrolized diethylaluminum chloride (DEACO) in 
toluene solution as cocatalyst. 
E. Silica supported cobalt tri-acetylacetonate: Co(acac).sub.3 /SiO.sub.2, 
in conjunction with ethylaluminum sesquichloride (EASC) as cocatalyst. 
F. Toluene solution nickel octoate (Ni(oct).sub.2)-triethylaluminum (TEAL) 
- boron trifluoride - etherate complex: Ni(oct).sub.2 
/TEAL/BF.sub.3.OEt.sub.2, pre-polymerized with 1,3-butadiene. 
1,3-Butadiene Polymerization Procedure: The polymerization of 1,3-butadiene 
(BD) was carried out in gas phase according to the following procedure: 
The one liter stirred autoclave was charged with 32 gram of dry carbon 
black N-650 used as fiuidization aid. Alternatively, 200 g of dehydrated 
salt (NaCl) mixed with 2 g of carbon black was used as bed in the reactor. 
The reactor was dried with a flow purge of N.sub.2 at 
90.degree.-100.degree. C. Once the internal reactor temperature was 
adjusted to 50.degree. C., aluminum alkyl (the same aluminum alkyl to be 
used as cocatalyst) was added to passivate the reactor. A measured amount 
of the catalyst was charged to the stirred reactor. The reactor was 
pressure purged with butadiene and the reactor was then pressurized with 
22 psig of monomer. The cocatalyst was injected to start the 
polymerization. The monomer was continuously flowing to maintain the the 
initial reactor pressure during the reaction time. The reaction was 
terminated by injection of a stabilizer package dissolved in alcohol. The 
weight of the black polymer corrected by ash content was used to determine 
the yield. 
BD Polymerization Termination Experiments: Gas phase BD polymerizations 
were performed at 50.degree. C. and 60.degree. C., at a monomer pressure 
of 35-37 psia, using a bed of mixed salt and carbon black in some 
experiments and only carbon in other experiments. BD flow was used to 
measure the catalyst activity, and the effect of the addition of a given 
inhibitor to an ongoing polymerization was reflected in decay of the BD 
flow. In all cases the selected terminating agent was introduced into the 
reactor when the reaction displayed high catalytic activity (high BD 
flow). The operating conditions with the different terminating agents are 
presented below. Reviving reaction attempts were done by addition of more 
cocatalyst and/or catalyst. 
Examples 1, 2 and 3: show that CO is not an effective terminating reaction 
agent for neodymium, nickel and cobalt catalysts. 
Examples 4 through 10: show the effectiveness of kill reagents with various 
catalysts. 
__________________________________________________________________________ 
Example 
Catalyst 
Catalyst 
Cocatalyst 
Kill Agent 
Reviving Treatment 
No. Type 
mmole 
Type mmole 
Type Mole Ratio 
Mole Ratio 
Comments 
__________________________________________________________________________ 
1 A 0.103 
TIBA CO/TIBA = 4 
None CO does not kill 
3.5 reaction 
2 D 0.060 
DEACO CO/Co = 11 
None CO does not kill 
3.4 reaction 
3 F 0.048 
TEAL + BF.sub.3 
CO/Ni = 10 
None CO does not kill 
1.94 reaction 
4 A 0.103 
TIBA EtOH/TIBA = 1 
TIBA/EtOH = 1.5 
EtOH kills reaction 
0.35 irreversibly 
5 A 0.103 
TIBA THF/TIBA = 0.5 
TIBA/THF = 1.5 
THF kills reaction 
0.35 irreversibly 
6 B 0.050 
TIBA NH.sub.3 /Al = 0.5 
TIBA/NH3 = 7 
Low activity 
3.5 Reactor vented/ 
recovery. 
purged 0.05 mmole 
Full activity 
Nd added. recovery 
7 B 0.050 
TIBA NH.sub.3 /Al = 0.5 
1.5 mmole DIBAH 
No activity recovery 
3.5 Reactor vented/ 
Full activity 
purged 0.05 mmole 
recovery 
Nd added 
8 C 0.030 
MAO + DIBAH = 4 
NH.sub.3 /Al = 1.7 
DIBAH/NH.sub.3 = 2.4 
NH3 kills reaction. 
Reactor vented/ 
40% activity 
purged recovery. 
0.05 mmole Nd added 
9 E 0.030 
EASC NH.sub.3 /EASC = 1 
3 mmole EASC 
No activity 
3.0 Reactor recovery. 
vented/purged 
Full activity 
0.03 mmole Co added 
recovery. 
10 F 0.024 
TEAL + BF.sub.3.OEt.sub.2 = 
NH.sub.3 /(Ni(oct).sub.2 + 
Reactor vented/ 
NH3 kills reaction 
0.96 TEAl + BF.sub.3) = 7 
purged No activity 
0.024 mmole Ni 
recovery. 
added 
__________________________________________________________________________ 
Example 11 (Fluidized Bed). In accordance with the process of the 
invention, a fluidized bed reaction system as described above, was 
operated as described below to produce polybutadiene. The polymer was 
produced under the following reaction conditions: 30.degree. C. reactor 
temperature and 100 psia reactor pressure. The volume of the reactor was 
55 ft.sub.3 ; the resin's weight inside the reactor was 112 lbs. The 
catalyst system employed was cobalt(acetylacetonate).sub.3 with partially 
hydrolyzed diethylaluminum chloride (DEACO) as co-catalyst. The production 
rate was 20 lb/h. The product had a Mooney value of 55. Carbon black is 
fed as the flow aid, at a rate equal to 5 to 50 PHR of polymer. 
Examples 12-16 (Fluidized Bed). The following examples set forth in tabular 
form, operating conditions for producing polymers in accordance with the 
invention. They illustrate the practice of the invention using different 
catalyst systems and differing cycle gas compositions. 
______________________________________ 
EXAMPLE NO. 
11 12 13 
PRODUCT: 
POLY- POLY- POLY- 
BUTADIENE BUTADIENE BUTADIENE 
______________________________________ 
Reaction Conditions: 
Temperature (.degree.C.) 
30 50 60 
Pressure (psi) 
100 110 100 
Superficial Velocity 
1.75 2.0 1.5 
(ft/s) 
Production Rate (lb/h) 
20 25 20 
Total Reactor Volume 
55 55 55 
(ft.sup.3) 
Reaction Zone Volume 
7.5 7.5 7.5 
(ft.sup.3) 
Bed Height (ft) 
7.0 7.0 7.0 
Bed Diameter (ft) 
1.17 1.17 1.17 
Bed Weight (lbs) 
112 112 112 
Cycle Gas 
Composition: 
N.sub.2 80 50 40 
Butadiene 20 50 60 
Styrene -- 
-- -- 
Catalyst: Co(acac).sub.3 * 
Nd(ver).sub.3 - 
Nd(ver).sub.3 - 
DEAC/silica 
DEAC/silica 
Co-catalyst: 
DEACO DIBAH DIBAH 
Gas Phase NH3 NH3 EtOH 
Kill Reagent: 
Molar Ratio/cocatalyst 
1 0.5 1 
-- 
Polymer Composition: 
Butadiene 100 100 100 
Styrene -- 
______________________________________ 
EXAMPLE NO. 
14 15 16 
PRODUCT: 
POLY- POLY- 
SBR BUTADIENE STYRENE 
______________________________________ 
Reaction Conditions: 
Temperature (.degree.C.) 
40 50 40 
Pressure (psi) 
110 100 100 
Superficial Velocity 
2.0 1.75 1.5 
(ft/s) 
Production Rate (lb/h) 
25 20 40 
Total Reactor Volume 
55 55 55 
(ft.sup.3) 
Reaction Zone Volume 
7.5 7.5 7.5 
(ft.sup.3) 
Bed Height (ft) 
7.0 7.0 7.0 
Bed Diameter (ft) 
1.17 1.17 1.17 
Bed Weight (lbs) 
112 112 112 
Cycle Gas 
Composition: 
N.sub.2 27.3 60 99.7 
Butadiene 72.5 40 -- 
Styrene .2 -- 0.3 
Catalyst: -- Nickel Cp.sub.2 ZrMe.sub.2 ** 
Co-catalyst: 
CpTiCl.sub.3 
TIBA MAO*** 
Promoter HF(Obu).sub.2 
Gas Phase MAO THF NH.sub.3 
Kill Reagent: 
Molar Ratio/cocatalyst 
NH3 1 0.5 
0.5 -- 
Polymer Composition: 
-- 
Butadiene 100 -- 
Styrene 100 
75 -- 
25 
-- 
______________________________________ 
*Cobalttriacetylacetonate 
**Dicyclopentadienylzirconiumdimethyl 
***Methylalumoxane