Title of Invention

An improved process for the polymerization of olefins.

Abstract This invention relates to an improved process for polymerization of olefins. More particularly it relates to an improved process of polymerization and copolymerization using a solid catalyst capable of giving olefm polymers and copolymers with high catalyst activity especially at high temperatures. The said catalyst comprises of atoms of Mg, halides, more particularly Cl, an electron donor compound such as tetrahydro furan, a neutral metallocene and a solid support based on a refractory oxide.
Full Text This invention relates to an improved process for polymerization of olefins. More particularly it relates to an improved process of polymerization and copolymerization using a solid catalyst capable of giving olefin polymers and copolymers with high catalyst activity especially at high temperatures. Still more particularly it relates to the process using an improved metallocene catalyst supported with the magnesium halide and silica. The process for the preparation of supported metallocane catalyst has been described and claimed in our copending patent application no. NF-323/96.
US Pat. No. 5,032,562, describes the preparation of a solid supported catalyst, by the reaction of dibutyl magnesium, a zirconium based neutral metallocene and a compound of a transition metal halide such as titanium tetrachloride and impregnating the said precursor on to silica in the presence onto silica in the presence of an aluminoxane activator. However, this catalyst results in bimodal distribution of molecular weights, which is not desirable in most of the applications where polyethylene is used.
JP 04,96,908, decribes another supported solid catalyst prepared by reacting aqueous magnesium halides in presence of silica, metallcene and an organoaluminum activator, which shows only moderate activity towards ethylene polymerization at 80°C.
Eur.Pat.No.EP 613,908, describes a silica-magnesium chloride supported metallocene catalyst which in the presence of an organoboron compound
polymerizes ethylene with high yield. However, the catalyst prepared according to this method is not very stable to storage and handling.
During the course of their research the inventors of the present invention have found that presence of small amounts of anhydrous magnesium chloride ( Anhydrous magnesium chloride commonly used as a support in high activity olefin polymerization catalyst is, often not, convenient because it is very brittle and undergoes easy attrition in the polymerization reactor. Silica is a well known support for gas phase as well as fluidized bed polymerization of olefins using titanium based Ziegler-Natta catalysts. However, when used with metallocene type catalysts silica supports show low polymerization activities. Therefore, a combination of the two, namely, silica and anhydrous magnesium chloride, offers a good balance to prepare catalysts with high activity, controlled particle size and good attrition strength.
In our copending patent application no. 437/del/97 we have described and
claimed a process for the preparation of improved supported metallocene
catalyst which is capable of being employed for the polymerization o
the olefins especially ethylene. The said catalyst comprises of atoms of Mg, halides
more particularly Cl., an electron donor compound such as tetrahydrofuran, a neutral metallocene and a solid support based on a refractory oxide.
It is therefore the object of the present invention to provide a process for polymerization and copolymerization of olefins using the said solid catalyst capable of producing high catalyst activity.
Another object of the present invention is to provide a process which could be carried out at especially at high temperatures and capable of being used either in gas or slurry phase.
Accordingly the present invention provides an improved process for the
polymerization of olefins which comprises; polymerizing an olefin or mixture thereof
selected from ethylene, propylene, a-olefins in presence of a solvent, a supported
metallocene catalyst of the general formula MgXaMb(ED)cCpd wherein x is selected
from Cl,Br,I or mixture thereof, M is transition metal chosen from the groups
IIB,IVB,VB,VIB preferably zirconium, ED is an electron doner compound such as
tetrahydrofuran and Cp is cyclopentadienyl wherein a is 1 to 50,preferably 1.5 to 2.5,
b is 0.01 to 1 preferably 0.02 to 0.05, c is 2 to 80 preferably 1.5 to 2.5, d is 0.03 tol
preferably 0.05 to 0.09 and an aluminoxane as cocatalyst wherein the molar ratio of
Al/Zr ranges between 500 to 10,000 in a hydrocarbon medium as herein described at
a temperature in the range of 50 to 150°C, at pressure ranging between 1 to 20 bar, for
a period of 10 minutes to 10 hours, scavenging the reaction mixture by addition of an
organo aluminum compound is selected from trimethylaluminium,
triisobutylaluminium, triethylaluminium to remove the last traces of impurities of solvent, separating the polymer by conventional methods like precipitating, filtering, washing the polymer with an organic solvent, drying the polymer to remove the solvent to obtain the product.

In an embodiment of the present invention the olefin used may be such as ethylene, propylene, a- olefins, preferably ethylene.
In another embodiment the supported metallocene catalyst used for the polymerization of the olefins may be prepared as per the process described and claimed in our copending patent application No,. NF-323/96.
In yet another embodiment the aluminoxane co-catalyst used may be such as methylaluminoxane, hexaisobutylaluminoxane, preferably methylaluminoxane.
In yet another embodiment the hydrocarbon medium used may be such as n-pentane, n-hexane, n-heptane, preferably n-hexane.
In another embodiment of the present invention the solvent used in the reaction may be such as toluene, xylene, n- hexane, preferably xylene.
In yet another embodiment of the present ivnention the metallocene catalyst may be partially or completely soluble in the solvent.
In yet another embodiment of the present invention the mole ratio of Al/Zr may range between 500 to 10,000 preferably 1000 to 5000.

In still another embodiment the organoaluminium compound used is may be such as trimethylaluminium, triisobutlyaluminium, triethylaluminium preferably trimethylaluminium.
In another embodiment of the present invention the mixture of olefin monomers comprises of ethylene and a second monomer chosen from amongst propylene, 1-butene, 1-hexene, 1-octene, 4-methyl-l-pentene, and cyclic olefins such as norbornene, cyclohexene, 2-vinyl-5-norbornene.
In another feature of the present invention the solid catalyst prepared as per the procedure described and claimed in our copending application No. NF-323/96 has Zr, Cl, Mg and THF in the wt % 0.36, 10, 2.5 and 15.7, respectively. The solid catalyst thus prepared has the general empirical formula In yet another feature of the present invention the catalyst precursor made according to the present invention has the formula
(Formula Removed)
Wherein,
X is selected from the group consisting of Cl, Br, I and may be mixtures thereof.

M indicates the transition metal which are chosen from the groups IIB,
IVB, VB, VIB of the Period Table.
ED is an electron donor compound,
a is 1 to 50, preferably, 1.5 to 2.5
b is 0.01 to 1 preferably, 0.02 to 0.05
c is 2 to 80, preferably, 1.5 to 2.5
d is 0.03 to 1, preferably , 0.05 to 0.09
CP= cyclopentadienyl
preferably MgCl2.75Zro.039THF2.25cP0.078. Wherein THF = tetrahydrofuran
The process of the present invention is described hereinbelow with examples which are illustrative only and should not be construed to limit the scope of the present invention in any manner.
Example-1
All glass equipments were heated under vacuum and flushed with nitrogen. All manipulations involving air-sensitive compounds were performed inside a Labconco Model 50004 inert atmosphere glove box continuously purged with

high purity N2 from a generator (Spantech Model NG 300-1) or under a positive pressure of high purity N2 using standard bench top inert atmosphere techniques. The solvent xylene used for polymerization used in each case freshly distilled over sodium under N2- 1-hexene was purified by distilling over CaH2- The intrinsic viscosities of the polymers obtained from the present invention were determined in decalin as solvent at 135°C using an Ubbelohde viscometer. In all these experiments, methylaluminoxane was added as a 5.4 wt% (as Al) solution in toluene. The MAO had a Me/Al ratio 1.7, free trimethylaluminum 31 wt% and Al content 10.9 wt% in toluene.
Crystallinity of the copolymer was measured by Differential Scanning Calorimetry (DSC). Polydispersities and molecular weight distribution of the polyethylene samples were measured by GPC (Waters 150C ALC/GPC) at 135°C in 1,2,4- trichlorobenzene. ji-Styragel columns 105, 104, 103, 500 A° were used and the peaks were calibrated using a standard polystyrene. A 0.3-0.4 % w/v solution was used at a flow rate of 1.0 mL/min.
ExampIe-2
Polymerization of ethylene was performed in a stirred glass reactor at one atmosphere pressure using xylene as diluent. A gas burette with a reservoir containing silicone oil was used to feed ethylene continuously to the cell. The

reaction cell was dried at 155°C overnight and cooled under ethylene. 15.8 mg catalyst (6.23 x 10'7 mol as Zr) was transferred into the cell inside the glove-box. 50 mL xylene was introduced into the cell using a hypodermic syringe. Polymerization was initiated by the addition of methylaluminoxane in toluene (3.2 x 10~3 mol as Al), keeping Al/Zr mol ratio 5000. The reaction temperature was maintained at 70°C. The reaction was terminated after 1/2 h by addition of acidified methanol. The polymer was filtered, washed with methanol and dried at 40°C under vacuum. Yield: 1.5 g
Activity : 53 Kg PE/g-Zr.h Intrinsic viscosity : 1.7 dL/g MWD = 2.67
Example-3
Polymerization of ethylene was performed in a stirred glass reactor at one atmosphere pressure using xylene as diluent. A gas burette with a reservoir containing silicone oil was used to feed ethylene continuously to the cell. The reaction cell was dried at 155°C overnight and cooled under ethylene. 15 mg catalyst (5.9 x 10'7 mol as Zr) was transferred into the cell inside the glove-box. Xylene (50 mL, previously treated with trimethylaluminum in order to remove the impurities) was introduced into the cell using a hypodermic syringe.

Polymerization was initiated by the addition of methylaluminoxane in toluene (5.9 x 10-4 mol as Al), keeping Al/Zr mol ratio 1000. The reaction temperature was maintained at 70 °C. The reaction was terminated after 1/2 h by addition of acidified methanol. The polymer was filtered, washed with methanol and dried at 40°C under vacuum. Yield: 1.45 g Activity : 54 Kg PE/g-Zr.h Intrinsic viscosity : 2.2 dL/g
ExampIe-4
Polymerization of ethylene was performed in a stirred glass reactor at one atmosphere pressure using xylene as diluent. A gas-burette with a reservoir containing silicone oil was used to feed ethylene continuously to the cell. The reaction cell was dried at 155°C overnight and cooled under ethylene. 15.3 mg
catalyst (6.04 x 10~7 mol as Zr) was transferred into the cell inside the glove-box. Xylene (50 mL, previously treated with trimethylaluminum in order to remove the impurities) was introduced into the cell using a hypodermic syringe. Polymerization was initiated by the addition of methylaluminoxane in toluene (1.208 x 10~3 mol as Al) , keeping Al/Zr mol ratio 2000. The reaction temperature was maintained at 70°C. The reaction was terminated after 1/2 h
by addition of acidified methanol. The polymer was filtered, washed with
methanol and dried at 40°C under vacuum.
Yield: 1.6g
Activity : 58 Kg PE/g-Zr.h
Intrinsic viscosity : 1.9 dL/g
MWD = 2.3
ExampIe-5
Polymerization of ethylene was performed in a stirred glass reactor at one atmosphere pressure using xylene as diluent. A gas-burette with a reservoir containing silicone oil was used to feed ethylene continuously to the cell. The reaction cell was dried at 155°C overnight and cooled under ethylene. 16 mg catalyst (6.5 x 10~7 mol as Zr) was transferred into the cell inside the glove-box. Xylene (50 mL, previously treated with trimethylaluminum in order to remove the impurities) was introduced into the cell using a hypodermic syringe. Polymerization was initiated by the addition of methylaluminoxane in toluene (3.25 x 10-3 mol as Al), keeping Al/Zr mol ratio 5000. The reaction temperature was maintained at 70 °C. The reaction was terminated after 1/2 h by addition of acidified methanol. The polymer was filtered, washed with methanol and dried at 40°C under vacuum. Yield: 2.1 g
Activity : 69 Kg PE/g-Zr.h Intrinsic viscosity : 1.8 dL/g MWD = 2.74
Example-6
Polymerization of ethylene was performed in a stirred glass reactor at one atmosphere pressure using xylene as diluent. A gas-burette with a reservoir containing silicone oil was used to feed ethylene continuously to the cell. The reaction cell was dried at 155°C overnight and cooled under ethylene. 15.1 mg
catalyst (5.9 x 10~7 mol as Zr) was transferred into the cell inside the glove-box. Xylene (50 mL, previously treated with trimethylaluminum in order to remove the impurities) was introduced into the cell using a hypodermic syringe. Polymerization was initiated by the addition of of methylaluminoxane in
toluene (2.95 x 10~3 mol as Al), keeping Al/Zr mol ratio 5000. The reaction
temperature was maintained at 60°C. The reaction was terminated after 1/2 h
by addition of acidified methanol. The polymer was filtered, washed with
methanol and dried at 40°C under vacuum.
Yield:1.5g
Activity : 55 Kg PE/g-Zr.h
Intrinsic viscosity : 2.6 dL/g
Example-7
Polymerization of ethylene was performed in a stirred glass reactor at one atmosphere pressure using xylene as diluent. A gas-burette with a reservoir containing silicone oil was used to feed ethylene continuously to the cell. The reaction cell was dried at 155°C overnight and cooled under ethylene. 15.3 mg
catalyst (6.04 x 10~7 mol as Zr) was transferred into the cell inside the glove-box. Xylene (50 mL, previously treated with trimethylaluminum in order to remove the impurities) was introduced into the cell using a hypodermic syringe. Polymerization was initiated by the addition of methylaluminoxane in toulene (3.02 x 10~3 mol as Al), keeping Al/Zr mol ratio 5000. The reaction temperature was maintained at 80°C. The reaction was terminated after 1/2 h by addition of acidified methanol. The polymer was filtered, washed with methanol and dried at 40°C under vacuum. Yield: 1.8g
Activity : 63 Kg PE/g-Zr.h Intrinsic viscosity : 0.9 dL/g
ExampIe-8
50 mL of xylene were (previously treated with trimethylaluminum in order to remove the impurities) introduced under N2 atmosphere into a stainless steel
Sotelem reactor with a capacity of 500 mL, equipped with a stirrer rotating at 1800 rpm and with a heating and cooling system. The reactor was heated to 200°C and cooled under N2 to a temperature 60 + 2 °C. A stainless steel reservoir was used to feed ethylene continuously. 15.8 mg of previously
prepared catalyst ( 6.2 x 10"7 mol as Zr) along with 20 mL xylene was transferred into the reactor by means of a separating funnel. Another 30 mL of xylene was added to the reactor through the separating funnel. The solvent was saturated with ethylene. Polymerization was initiated by the addition of
methylaluminoxane in toluene (3.1 x 10'3 mol as Al), keeping Al/Zr mol ratio
5000 and a ethylene pressure of 5 bar. The reaction was terminated after 1/2 h
by adding acidified methanol. The polymer was filtered, washed with methanol
and dried at 40-50°C under vacuum.
Yield: 5 g
Activity : 177 kg PE/g-Zr. h.
Example-9
50 mL of xylene were (previously treated with trimethylaluminum in order to remove the impurities) introduced under N2 atmosphere into a stainless steel Sotelem reactor with a capacity of 500 mL, equipped with a stirrer rotating at 1800 rpm and with a heating and cooling system. The reactor was heated to 200°C and cooled under N2 to a temperature 70 + 3 °C. A stainless steel
reservoir was used to feed ethylene continuously. 21.3 mg of previously prepared catalyst ( 8.4 x 10'7 mol as Zr) along with 20 mL xylene was transferred into the reactor by means of a separating funnel. Another 30 mL of xylene was added to the reactor through the separating funnel. The solvent was saturated with ethylene. Polymerization was initiated by the addition of
methylaluminoxane in toluene (4.2 x 10~3 mol as Al), keeping Al/Zr mol ratio
5000 and a ethylene pressure of 5 bar. The reaction was terminated after 1/2 h
by adding acidified methanol. The polymer was filtered, washed with methanol
and dried at 40-50°C under vacuum.
Yield : 7 g
Activity : 183 kg PE/g-Zr. h
Intrinsic viscosity : 2.6 dL/g
Example-10
50 mL of xylene were (previously treated with trimethylaluminum in order to remove the impurities) introduced under N2 atmosphere into a stainless steel Sotelem reactor with a capacity of 500 mL, equipped with a stirrer rotating at 1800 rpm and with a heating and cooling system. The reactor was heated to 200°C and cooled under N2 to a temperature 80 ± 2 °C. A stainless steel reservoir was used to feed ethylene continuously. 15.7 mg of previously prepared catalyst ( 6.2 x 10~7 mol as Zr) along with 20 mL xylene was
transferred into the reactor by means of a separating funnel. Another 30 mL of xylene was added to the reactor through the separating funnel. The solvent was saturated with ethylene. Polymerization was initiated by the addition of
rnethylaluminoxane in toluene (3.1 x 10'3 mol as Al), keeping Al/Zr mol ratio
5000 and a ethylene pressure of 5 bar. The reaction was terminated after 1/2 h
by adding acidified methanol. The polymer was filtered, washed with methanol
and dried at 40-50°C under vacuum.
Yield: 9.5 g
Activity : 336 kg PE/g-Zr. h
Intrinsic viscosity : 2.44 dL/g
MWD = 3.07
Example-11
50 mL of xylene were (previously treated with trimethylaluminum in order to remove the impurities) introduced under N2 atmosphere into a stainless steel Sotelem reactor with a capacity of 500 mL, equipped with a stirrer rotating at 1800 rpm and with a heating and cooling system. The reactor was heated to 200°C and cooled under N2 to a temperature 100 ± 2 °C. A stainless steel
reservoir was used to feed ethylene continuously. 21.3 mg of previously prepared catalyst ( 8.4 x 10'? mol as Zr) along with 20 mL xylene was transferred into the reactor by means of a separating funnel. Another 30 mL of
xylene was added to the reactor through the separating funnel. The solvent was
saturated with ethylene. Polymerization was initiated by the addition of
methylaluminoxane in toluene (4.2 x 10'3 mol as Al), keeping Al/Zr mol ratio
5000 and a ethylene pressure of 5 bar. The reaction was terminated after 1/2 h
by adding acidified methanol. The polymer was filtered, washed with methanol
and dried at 40-50°C under vacuum.
Yield: 25 g
Activity : 670 kg PE/g-Zr. h
Intrinsic viscosity : 1.8 dL/g
MWD = 2.44
Example-12
50 mL of xylene were (previously treated with trimethylaluminum in order to remove the impurities) introduced under N2 atmosphere into a stainless steel Sotelem reactor with a capacity of 500 mL, equipped with a stirrer rotating at 1800 rpm and with a heating and cooling system. The reactor was heated to 200°C and cooled under N2 to a temperature 105 + 2 °C. A stainless steel reservoir was used to feed ethylene continuously. 21.3 mg of previously
prepared catalyst ( 8.4 x 10"7 mol as Zr) along with 20 mL xylene was transferred into the reactor by means of a separating funnel. Another 30 mL of xylene was added to the reactor through the separating funnel. The solvent was
saturated with ethylene. Polymerization was initiated by the addition of
methylaluminoxane in toluene (4.2 x 10'3 mol as Al), keeping Al/Zr mol ratio
5000 and a ethylene pressure of 5 bar. The reaction was terminated after 1/3 h
by adding acidified methanol. The polymer was filtered, washed with methanol
and dried at 40-50°C under vacuum.
Yield: 21 g
Activity : 822 kg PE/g-Zr. h
Intrinsic viscosity : 1.75 dL/g
MWD = 3.05
Example-13
50 mL of xylene were (previously treated with trimethylaluminum in order to remove the impurities) introduced under N2 atmosphere into a stainless steel Sotelem reactor with a capacity of 500 mL, equipped with a stirrer rotating at 1800 rpm and with a heating and cooling system. The reactor was heated to 200 °C and cooled under N2 to a temperature 110 ± 2 °C. A stainless steel reservoir
was used to feed ethylene continuously. 18.8 mg of previously prepared catalyst ( 7.4 x 10~7 mol as Zr) along with 20 mL xylene was transferred into the reactor by means of a separating funnel. Another 30 mL of xylene was added to the reactor through the separating funnel. The solvent was saturated with ethylene. Polymerization was initiated by the addition of
methylaluminoxane in toluene (3.7 x 10'3 mol as Al), keeping Al/Zr mol ratio
5000 and a ethylene pressure of 5 bar. The reaction was terminated after 1/2 h
by adding acidified methanol. The polymer was filtered, washed with methanol
and dried at 40-50°C under vacuum.
Yield: 30 g
Activity : 890 kg PE/g-Zr. h
Intrinsic viscosity : 1.7 dL/g
MWD = 2.78
Example-14
50 mL of xylene were (previously treated with trimethylaluminum in order to remove the impurities) introduced under N2 atmosphere into a stainless steel
Sotelem reactor with a capacity of 500 mL, equipped with a stirrer rotating at 1800 rpm and with a heating and cooling system. The reactor was heated to 200°C and cooled under N2 to a temperature 80°C. A stainless steel reservoir
was used to feed monomer ethylene and hydrogen continuously . 17.2 mg of previously prepared catalyst ( 6.8 x 10~7 mol as Zr) along with 20 mL xylene was transferred into the reactor by means of a separating funnel. Another 30 mL of xylene was added to the reactor through the separating funnel. 100 mL of hydrogen was introduced into the reservoir. The solvent was saturated with ethylene and hydrogen mixture. Polymerization was initiated by the addition of
ethylaluminoxane in toluene (3.4 x 10'3 mol as Al), keeping Al/Zr mol ratio
5000 and maintaining pressure of 5 bar. The reaction was terminated after 1/2 h
by adding acidified methanol. The polymer was filtered, washed with methanol
and dried at 40-50°C under vacuum.
Yield: 3.5 g
Activity : 113 kg PE/g-Zr. h
Intrinsic viscosity : 1.48 dL/g
Example 15
50 mL of xylene were (previously treated with trimethylaluminum in order to remove the impurities) introduced under N£ atmosphere into a stainless steel
Sotelem reactor with a capacity of 500 mL, equipped with a stirrer rotating at 1800 rpm and with a heating and cooling system. The reactor was heated to 200°C and cooled under N2 to a temperature 90°C. A stainless steel reservoir was used to feed monomer ethylene and hydrogen continuously . 18 mg of previously prepared catalyst (7.1 x 10-7 mol as Zr) along with 20 mL xylene was transferred into the reactor by means of a separating funnel. Another 30 mL of xylene was added to the reactor through the separating funnel. 50 mL of hydrogen was introduced into the reservoir.The solvent was saturated with ethylene and hydrogen mixture. Polymerization was initiated by the addition of
methylaluminoxane in toluene (3.55 x 10"3 mol as Al), keeping Al/Zr mol ratio
5000 and maintaining pressure of 5 bar. The reaction was terminated after 1/2 h
by adding acidified methanol. The polymer was filtered, washed with methanol
and dried at 40-50 °C under vacuum.
Yield: 17 g
Activity : 525 kg PE/g-Zr. h
Intrinsic viscosity : 1.1 dL/g
MWD = 2.64
Example-16
Polymerization of ethylene was performed in a stirred glass reactor at one atmosphere pressure using xylene as diluent. A. gas-burette with a reservoir containing silicone oil was used to feed ethylene continuously to the cell. The reaction cell was dried at 155°C overnight and cooled under ethylene. 8.7 mg
catalyst (4.8 x 10"6 mol as Ti) was transferred into the cell inside the glove-box. Xylene (50 mL) was introduced into the cell using a hypodermic syringe. Polymerization was initiated by the addition of methylaluminoxane in toluene (2.4 x 10-3 mol as Al), keeping Al/Ti mol ratio 500. The reaction temperature was maintained at 30 °C. The reaction was terminated after 1/2 h by addition of acidified methanol. The polymer was filtered, washed with methanol and dried at 40°C under vacuum. Yield : 0.82 g
Activity : 8.72Kg PE/g-Ti.h Intrinsic viscosity : 3.30 dL/g
Example-17
Polymerization of ethylene was performed in a stirred glass reactor at one atmosphere pressure using xylene as diluent. A gas-burette with a reservoir containing silicone oil was used to feed ethylene continuously to the cell. The reaction cell was dried at 155°C overnight and cooled under ethylene. 7.3 mg
catalyst (4.02 x 10"6 mol as Ti) was transferred into the cell inside the glove-box. Xylene (50 mL) was introduced into the cell using a hypodermic syringe. Polymerization was initiated by the addition of methylaluminoxane in toluene
(2.01 x 10"3 mol as Al), keeping Al/Ti mol ratio 1000. The reaction
temperature was maintained at 30°C. The reaction was terminated after 1/2 h
by addition of acidified methanol. The polymer was filtered, washed with
methanol and dried at 40°C under vacuum.
Yield : 0.9 g
Activity : 11.1 Kg PE/g-Ti.h
Intrinsic viscosity : 3.01 dL/g
Example-18
Polymerization of ethylene was performed in a stirred glass reactor at one atmosphere pressure using xylene as diluent. A gas-burette with a reservoir containing silicone oil was used to feed ethylene continuously to the cell. The reaction cell was dried at 155°C overnight and cooled under ethylene. 5.3 mg
catalyst (2.9 x 10~6 mol as Ti) was transferred into the cell inside the glove-box. Xylene (50 mL) was introduced into the cell using a hypodermic syringe. Polymerization was initiated by the addition of methylaluminoxane in toluene
(1.5 x 10"3 mol as Al), keeping Al/Ti mol ratio 2000. The reaction temperature
was maintained at 30°C. The reaction was terminated after 1/2 h by addition of
acidified methanol. The polymer was filtered, washed with methanol and dried
at 40°C under vacuum.
Yield : 0.78 g
Activity : 22.7 Kg PE/g-Ti.h
Intrinsic viscosity : 2.88 dL/g
Example-19
Polymerization of ethylene was performed in a stirred glass reactor at one atmosphere pressure using xylene as diluent. A gas-burette with a reservoir containing silicone oil was used to feed ethylene continuously to the cell. The
reaction cell was dried at 155°C overnight and cooled under ethylene. 8.2 mg catalyst (4.5 x 10'6 mol as Ti) was transferred into the cell inside the glove-box. Xylene (50 mL) was introduced into the cell using a hypodermic syringe. Polymerization was initiated by the addition of methylaluminoxane in toluene (2.25 x lO'3 mol as Al), keeping Al/Ti mol ratio 500. The reaction temperature was maintained at 70°C. The reaction was terminated after 1/2 h by addition of acidified methanol. The polymer was filtered, washed with methanol and dried at 40°C under vacuum.
Yield : 0.64 g Activity : 7.2 Kg PE/g-Ti.h Intrinsic viscosity : 2.94 dL/g MWD = 2.81
Example-20
50 mL of xylene were (previously treated with trimethylaluminum in order to remove the impurities) introduced under N2 atmosphere into a stainless steel
Sotelem reactor with a capacity of 500 mL, equipped with a stirrer rotating at 1800 rpm and with a heating and cooling system. The reactor was heated to 200°C and cooled under N2 to a temperature 55 + 2 °C. A stainless steel reservoir was used to feed ethylene continuously. 12.4 mg of previously prepared catalyst ( 6.8 x 10~6 mol as Ti) along with 20 mL xylene was
transferred into the reactor by means of a separating funnel. Another 30 mL of xylene was added to the reactor through the separating funnel. The solvent was saturated with ethylene. Polymerization was initiated by the addition of
methylaluminoxane in toluene (3.4 x 10~3 mol as Al), keeping Al/Ti mol ratio
1000 and a ethylene pressure of 5 bar. The reaction was terminated after 1/2 h
by adding acidified methanol. The polymer was filtered, washed with methanol
and dried at 40-50°C under vacuum.
Yield : 3.35 g
Activity : 20.4 kg PE/g-Ti. h
Intrinsic viscosity : 4.44 dL/g
Example-21
50 mL of xylene were (previously treated with trimethylaluminum in order to remove the impurities) introduced under N2 atmosphere into a stainless steel Sotelem reactor with a capacity of 500 mL, equipped with a stirrer rotating at 1800 rpm and with a heating and cooling system. The reactor was heated to 200°C and cooled under N2 to a temperature 55 + 2 °C. A stainless steel
reservoir was used to feed ethylene continuously. 4 mg of previously prepared catalyst ( 2.15 x 10"6 mol as Ti) along with 20 mL xylene was transferred into the reactor by means of a separating funnel. Another 30 mL of xylene was added to the reactor through the separating funnel. The solvent was saturated
with ethylene. Polymerization was initiated by the addition of methylaluminoxane in toluene (1.2 x 10'3 mol as Al), keeping Al/Ti mol ratio 5000 and a ethylene pressure of 5 bar. The reaction was terminated after 1/3 h by adding acidified methanol. The polymer was filtered, washed with methanol and dried at 40-50°C under vacuum. Yield: 2.Ig
Activity : 41 kg PE/g-Ti. h Intrinsic viscosity : 3.80 dL/g
Example-22
Copolymerization of ethylene and 1-hexene was performed in a stirred glass reactor at one atmosphere pressure using xylene as diluent. A gas-burette with a reservoir containing silicone oil was used to feed ethylene continuously to the cell. The reaction cell was dried at 155°C overnight and cooled under ethylene.
12.4 mg catalyst (6.52 x 10"? mol as Zr) was transferred into the cell inside the glove-box. Xylene (50 mL, previously treated with trimethylaluminum in order to remove the impurities) was introduced into the cell using a hypodermic syringe followed by addition of 1-hexene (8.056 x 10~3 mol). Polymerization
was initiated by the addition of methylaluminoxane in toulene (3.30 x 10'3 mol as Al), keeping Al/Zr mol ratio 5000. The reaction temperature was maintained at 70°C. The reaction was terminated after 1/2 h by addition of acidified
methanol. The polymer was filtered, washed with methanol and dried at 40°C
under vacuum.
Yield: 1.8 g
Activity : 60 Kg PE/g-Zr.h
Intrinsic viscosity : 1.47 dL/g
Crystallinity : 45.33 %
ExampIe-23
Copolymerization of ethylene and 1-hexene was performed in a stirred glass reactor at one atmosphere pressure using xylene as diluent. A gas-burette with a reservoir containing silicone oil was used to feed ethylene continuously to the cell. The reaction cell was dried at 155°C overnight and cooled under ethylene.
12.3 mg catalyst (6.47 x 10-7 mol as Zr) was transferred into the cell inside the glove-box. Xylene (50 mL, previously treated with trimethylaluminum in order to remove the impurities) was introduced into the cell using a hypodermic syringe followed by addition of 1-hexene (0.012 mol). Polymerization was initiated by the addition of methylaluminoxane in toulene (3.25 x 10"3 mol as Al), keeping Al/Zr mol ratio 5000. The reaction temperature was maintained at 60°C. The reaction was terminated after 1/2 h by addition of acidified methanol. The polymer was filtered, washed with methanol and dried at 40°C under vacuum.
Yield: 1.7g
Activity : 56 Kg PE/g-Zr.h Intrinsic viscosity : 0.985 dL/g Crystallinity : 31.3 %
Example-24
A metallocene catalyst supported on silica was prepared and the amount of zirconium on the solid catalyst was found to be 0.53%.
Polymerization of ethylene was performed in a stirred glass cell at one atmosphere pressure using xylene as diluent. A gas-burette with a reservoir containing silicone oil was used to feed ethylene continuously to the cell. The reaction cell was dried at 155°C overnight and cooled under ethylene. 10.3 mg
catalyst (5.98 x 10-7 mol as Zr) was transferred into the cell inside the glove-box. Xylene (50 mL, previously treated with trimethylaluminum in order to remove the impurities) was introduced into the cell using a hypodermic syringe. Polymerization was initiated by the addition of methylaluminoxane in toulene
.(3 x 10-3 mol as Al), keeping Al/Zr mol ratio 5000. The reaction temperature was maintained at 70°C. The reaction was terminated after 1/2 h by addition of acidified methanol. The polymer was filtered, washed with methanol and dried at 40°C under vacuum.
Yield: 1.2g
Activity : 44 Kg PE/g-Zr.h Intrinsic viscosity : 1.5 dL/g MWD = 3.57
It is observed from an examination of comparative example with those of example that incorporation of low amounts of anhydrous magnesium chloride ( Table-1 : Ethylene Polymerization using SiO2 supported and SiO2-MgCl2 supported Cp2ZrCl2/MAO catalyst8

(Table Removed)
a All polymerization were carried out in xylene (50 mL); Al/Zr = 5000; T = 70°C; time = 30 min; P= 1 atm of ethylene.





We Claim:
1. An improved process for the polymerization of olefins which comprises;
polymerizing an olefin or mixture thereof selected from ethylene, propylene, a-
olefins in presence of a solvent, a supported metallocene catalyst of the general
formula MgXaMb(ED)cCpd wherein x is selected from Cl,Br,I or mixture thereof,
M is transition metal chosen from the groups IIB,IVB,VB,VIB preferably
zirconium, ED is an electron doner compound such as tetrahydrofuran and Cp is
cyclopentadienyl wherein a is 1 to 50,preferably 1.5 to 2.5, b is 0.01 to 1
preferably 0.02 to 0.05, c is 2 to 80 preferably 1.5 to 2.5, d is 0.03 tol preferably
0.05 to 0.09 and an aluminoxane as cocatalyst wherein the molar ratio of Al/Zr
ranges between 500 to 10,000 in a hydrocarbon medium as herein described at a
temperature in the range of 50 to 150°C, at pressure ranging between 1 to 20 bar,
for a period of 10 minutes to 10 hours, scavenging the reaction mixture by
addition of an organo aluminum compound is selected from trimethylaluminium,
triisobutylaluminium, triethylaluminium to remove the last traces of impurities of
solvent, separating the polymer by conventional methods like precipitating,
filtering, washing the polymer with an organic solvent, drying the polymer to
remove the solvent to obtain the product.
2. A process as claimed in claim 1 wherein the aluminoxane co-catalyst used is
selected from methylaluminoxane, ethylaluminoxane, hexaisobutylaluminoxane.
3. A process as claimed in claim 1 wherein the hydrocarbon medium used is selected
from n- pentane, n-hexane, n-heptane.
4. A process as claimed in claim 1 wherein the solvent used in the reaction is
selected from toluene, xylene, n-hexane, n-heptane.
5. A process as claimed in claim 1 wherein the metallocene catalyst is partially or
completely soluble in the solvent.
6. A process as claimed in claim 1 wherein the preferable molar ratio of Al/Zr
ranges between 1000 to 5000.

7. A process as claimed in claim 1 wherein the mixture of olefin monomers
comprises of ethyl ene and a second monomer chosen from amongst propylene, 1 -
butene, 1-hexene, 1-octene, 4-methyl-l-pentene, and cyclic olefins such as
norbornene, cyclohexene, 2-vinyl-5-norbornene.
8. An improved process for the polymerization of olefins substantially described
herein with references to the examples.


Documents:

421-del-1997-abstract.pdf

421-del-1997-claims.pdf

421-del-1997-complete specification (granted).pdf

421-del-1997-correspondence-others..pdf

421-del-1997-correspondence-po.pdf

421-del-1997-description (complete).pdf

421-del-1997-form-1.pdf

421-del-1997-form-19.pdf

421-del-1997-form-2.pdf

421-del-1997-form-3.pdf

421-del-1997-petition-others.pdf


Patent Number 199590
Indian Patent Application Number 421/DEL/1997
PG Journal Number 37/2008
Publication Date 12-Sep-2008
Grant Date 12-Jan-2007
Date of Filing 21-Feb-1997
Name of Patentee Council of Scientific and Industrial Research
Applicant Address Rafi Marg, New Delhi-110 001.
Inventors:
# Inventor's Name Inventor's Address
1 Soumen Sensarma National Chemical Laboratory, Pune 411 008.
2 Swaminathan Sivaram National Chemical Laboratory, Pune 411 008.
PCT International Classification Number C08F 10/00
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA