FR2539134A1 - Process for the preparation of catalyst compositions for olefin polymerisation, catalyst compositions prepared by this process and application of the said compositions - Google Patents

Abstract

This process is of the type in which, in a first stage, an element of groups IVA to VIA of the Periodic Classification is reacted with an organometallic compound of an element of groups I to III. In a second stage an organometallic compound of an element of groups I to III, which is identical or otherwise to the preceding one is added to the product of this reaction. According to the invention an olefin is reacted with the products present during one of these stages, between them or after the second stage.

Description

Process for the preparation of catalytic compositions
for the polymerization of olefins, compositions
catalysts prepared by this process and application
said compositions.

 The present invention relates to a process for the preparation of olefin polymerization catalyst compositions. It also relates to the catalytic compositions prepared by this process and the application of these compositions to the polymerization of alpha-olefins.

 It is well known to use, for the polymerization of alpha-olefins, according to a so-called low-pressure process, catalysts commonly known as Ziegler catalysts.

 These catalysts are mixtures of compounds of the elements of groups IV to VI of the Periodic Table of Elements, in particular titano trichloride, and Group I to III orgamometallic compounds, in particular organoaluminum compounds.

 Many brovets concerning these catalytic compositions and their application to the peelmerization of e @ olefins have been deposited, the use of a determined permottant catalyst to obtain a partial quality of polyolefin, suitable for specific applications.

 One of the characteristics of the polyolefin obtained, for example ethylene oxide, is its polydispersity. The greater the polydispersity and the greater the molecular weight range of the different polyolefin molecules.

The polydispersity of a polyoffin can be defined
Mw by the ratio, Mw denoting the molecular mass
Mn average weight and Mn designating the number average molecular weight, these two values can be obtained by gel permeation chromatography.

 The polydispersity of a polyolefin can also be defined by the ratio I21.6 / I5, I21.6 and I5 being respectively the melt indexes measured according to ASTM standard D 1238-79 with a weight of 21.6 kg and 5 kg. .

For the extrusion blow molding of hollow bodies, it is necessary that the polydispersity is important, because it is necessary that the polyethylene contains:
on the one hand, molecules having a high molecular weight, so as to ensure the rigidity of the hollow body,
- On the other hand, molecules having a low ocular molecular weight, so as to facilitate the hot work of the polyethylene, during its implementation, for example extrusion blow molding.

 It has therefore been decided to develop polymerization processes that make it possible to obtain polyolefins of high polydispersity. For example, the so-called cascade polymerization process is used in several steps, in which the operating conditions (temperature, pressure, sequester time and concentration of the various reagents and catalysts) vary from one stage to another. and can obtain, at each step, a polyolefin of different molecular mass from those obtained in the other steps. The final polyolefin obtained can thus have the desired polydispersity. One such method, for example in French Patent No. 1,418,396, has the disadvantage of having several steps and therefore requiring more reactors operating with different and non-independent operating conditions. where, of course, a great difficulty of conduct of the polyolefin manufacturing unit, long residence times and a high production cost.

 In order to overcome this drawback, the Applicant has developed a catalyst for obtaining a controlled polydispersity polyelfin and, in particular, a large one, without however requiring the implementation of a multi-stage polymerization process.

 This catalyst was the subject of French patent application No. 82 02 238, filed on February 11, 1982, by the same Applicant.

 An originality of this catalyst lies in its preparation, during which a treatment with hydrogen is carried out.

 Continuing its work, the Applicant has painted a process for the preparation of a catalyst making it possible to obtain a polyethylene of controlled polydispersity with yields even greater than those obtained with the catalyst of Application No. 82 02 258, although they are already high.

 One of the aims of the present invention is therefore to obtain polyolefins, in particular polyethylene, from controlled polydispersity.

 Another object of the invention is to obtain polyolefins, especially polyethylene, controlled polydispersity with high yields.

To this end, the subject of the invention is a process for the preparation of a catalytic composition for the polymerization of olefins, said process consisting in:
1) in a first step, to react s
at least one compound A of an element selected from the group consisting of elements from groups IVA to
VIA of the periodic table of the elements, said element being in said compound A to a degree of oxidation greater than the minimum degree of oxidation of said element, with
at least one organometallic compound B of an element selected from the group consisting of the elements of groups I to III of the periodic table of elements;
2) in a second step, to add, at least one operation, to the reaction product of the first step, at least one compound B 'chosen in the same family as that of compound B, compound lodit B' being identical or different from compound B,
said method being characterized in that, during and / or after the first step, and / or during and / or after the second step, an olefin is reacted with the products in the presence.

 A second and third object of the invention are catalysts prepared by the process according to the invention and their application to the polymerization of alpha-olefins.

 In the process according to the invention, the compound A may in particular be a halide of titanium or vanadium.

It may be, in particular, a tetravalent titanium compound, such as titanium tetrachlure, or a titanium alkoxy halide of the general formula
Ti (OR) 4-nXn, where X is a halogen element, n is such that 1 # n # 4 and R is a hydrocarbon radical having 2 to 8 carbon atoms.

 Compound B may be, in particular, an organoaluminum or organozinc compound, chlorinated or non-chlorinated, for example isoprenylaluminum, triethylaluminium, triisobutylaluminium, trioctylaluminium or diethylzine.

 The preparation of the catalytic composition may be carried out in a solvent or dispersing agent which is inert with respect to the bodies in the presence, such as those generally used in processes for the polymerization of olefins using Ziegler catalysts, for example the aliphatic or cyclic hydrocarbons (saturated or aromatic), especially hexane or heptane, or mixtures of such hydrocarbons.

 Compounds A and B can also be undiluted.

 In particular, water and oxygen must be removed or introduced in a controlled manner into the inert agents used as solvent or dispersant, as well as into the reactor atmosphere.

The reaction of step 1 can be carried out at a temperature between -80 ° C. and 100 ° C. and preferably between -50 ° C. and 20 ° C.
The pressure can be between the vapor pressure of the solvent at the temperature in question and 18.106
Pascals absolute and, preferably, between 0.2.105 Pascal and 30.105 Pascals absolute.

 The duration of step 1 may be between 1 minute and 48 hours, although shorter or longer times may be considered.

 The second step of the process consists in adding to the reaction product of compounds A and B, obtained at the end of step 1, a compound B ', which may be identical to or different from B, but which is part of the family of organometallic compounds as defined above.

 This second step can be done in several operations, two for example.

 The characteristic of the process according to the invention therefore consists in reacting an olefin on the products in the presence, during the preparation of the catalytic composition.

The amount of olefin used is small. More specifically, it is preferably less than 10 millimoles and, preferably, less than or equal to 0.01 and 5 millimeters, per milliatem of the element of Groups IVA to
VIA present.

 The olefin that can be used in the preparation process may be a branched linear olefin.

The Domanderesse has thus successfully used butene-1, 4,4-dimethyl-1-pontene and hexene-1.

 The reaction with the olefin can be carried out during the first step, between the first and the second step, during the second step, between or during the different operations of the second step, when this is done in several operations, after the second step or in several times, during the first step and after the second step for example.

The operating conditions of the reaction with olefin, when this reaction is carried out after the first step, can be between the following
temperature between -20 ° C. and 150 ° C., preferably between 20 ° C. and 100 ° C.
pressure comprised between the vapor pressure of the solvent at the temperature in question and 18.106 absolute Pascals and, preferably, between 0.2.10 @ Pascals and 30.105 Pascals absolute,
- duration, preferably, between 1 minute and 24 hours, although shorter or longer periods can be envisaged.

 During the process according to the invention, a treatment with hydrogen, as described in French Patent Application No. 82 02 258 of February 11, 1982, can also advantageously be carried out.

 After the first step, the product obtained can be diluted in the solvent, which also contains a small amount of compound B, in order to remove traces of water or polar compounds that may be present, and to be stored.

 The catalytic compositions prepared by the process according to the invention can be used for homopolymerization or copolymerization of alphaolefins. They are particularly applicable to the homopolymerization of ethylene or its copolymerization with other alpha-olefins, such as propylene or butene-1 by example.

 The polymerization or copolymerization can be carried out according to known polymerization techniques, one hundredinu or batchwise. The reaction can be carried out in the gas phase, in solution or in suspension.

In the solution or suspension polymerizations, it is possible to use, as a solvent or dispersion agent, the inert liquids with respect to the reagents commonly used in the low pressure polymerization or copolymerization process using catalysts.
Ziegler previously described. As dispersing agent or as a solvent, the monomers themselves, maintained in the liquid state by their saturating vapor pressure at the temperature at which the polymerization is carried out, can be used.

 The polymerization can be carried out, in the presence or absence of hydrogen, at a temperature of between 20 and 250 ° C., preferably between 60 ° and 1400 ° C., and at a pressure of up to 60 × 10 5 Pascals, preferably between 5.105 and 35.105 Pascals. Higher or lower pressures or temperatures can be envisaged.

 The following example relates to the preparation of catalytic polymerization compositions, according to a known process and to the process according to the invention, and the polymerization and copolymerization of ethylene using the compositions thus prepared. This example, of course, is not limiting in nature.

 It is specified that, in this example, the concentrations of the aluminum compounds used, which are not exactly defined compounds, are expressed in millimoles, assuming that each mole of the compound contains only one aluminum atom.

EXAMPLE
I - TEST WITNESS T
This test relates to the preparation of a control catalytic composition CT, the preparation of which is part of the state of the art.

 It also relates to the polymerization of ethylene using said catalyst composition.

 Preparation of the control catalytic composition CT.

 The product of the reaction, under an atmosphere inert with 00C, titanium tetrachloride Ti Cl4 and an organoaluminum compound, in this case isoprenylaluminum. hereinafter referred to as IPRA (see, for example, J. BOOR Jr., "Ziegler Natta Catalysts and Polymerizations", page 110).

In a thermostatically controlled reactor, with a capacity of one liter, equipped with a hydrogen supply and with an ethylene feed, 900 cm3 of dry hexane containing 0.082 mmol of the product prepared as indicated above and 1 g / l of hexane are introduced. , 25 millimole of IPRA. The aluminum ratio is therefore close to 15. The reactor is maintained
titanium at 20 C during this introduction, the reactor being flushed with a stream of nitrogen. The catalytic composition CT is thus obtained.

Polymerization of ethylene using the
CT catalytic composition
The reactor is isolated. The reactor is then introduced into the reactor at 20 ° C., first of all with hydrogen, in such a quantity that the pressure inside the reactor is 3.6 × 10 5 Pascals abselus, then with ethylene, such that the pressure of 110105 Pascals absolute, when the temperature of the reactor is raised to 80 C.

Ethylene polymerizes and ethylene is continuously introduced into the reactor so as to maintain the pressure inside the reactor at 11.105 Pascals absolute for the duration of the polymerization, which is set at 90 minutes.

 Polymerization is stopped by interrupting the introduction of ethylene into the reactor, rapidly lowering the temperature to 20 ° C and introducing into the reactor methanol containing hydrochloric acid.

The results of the polymerization are as follows @
polyethylene mass obtained: 128.9 g,
- productivity (mass in g of
polyethylene obtained by g
of titanium in the composition @ 2013 gp @ / gTi,
catalytic) t
-% by weight of waxes (*) obtained: 0.31,
density in g / cm 3: 0.960,
- melt index according to ASTM D standard
1238, load 5 kg, I5: 2.5,
- melt index according to ASTM D standard
1238, load 21.6 kg, I21.6: 26.1,
polydispersity I21.6: 10.4.

I5
(*) s the waxes are the products obtained soluble
in the polymerization solvent.

II - TESTS A, B, C
These tests concern the preparation of catalytic compositions according to the invention, as well as the polymerization and copolymerization of ethylene using these compositions.

A1 TEST
Preparation of the catalytic composition CA1
28.8 milliliters of a solution of isoprenylaluminum in hexane containing 20.47 millimoles of IPRA, 40.94 millimoles of Ti C14 and 40.94 millimoles are reacted at 0 ° C. under an inert atmosphere.
The product obtained is diluted with 178 milliliters of a solution of IPRA in hexane containing 2.5 millimol of IRPA per liter. This gives the suspension SA1, which can be stored.

 In a thermostatically controlled reactor with a capacity of one liter, equipped with a supply of hydrogen and an ethylene feed, is introduced 520 cm3 of dry hexane containing 0.33 milliliters of the suspension SA. titanium milliatome and 1.23 millimole IPRA. The titanium aluminum ratio is therefore close to 15.

The reactor is maintained at 20 ° C. during this introduction, the reactor being flushed with a stream of nitrogen
The catalytic composition CA1e is thus obtained
Polymerization of ethylene using the catalytic CA1 composition.

 The polymerization is carried out in the same way as with the catalytic composition CT.

The results of the polymerization are as follows
polyethylene mass obtained: 239.4 g,
- productivity t60951
by weight of waxes obtained: 0.33,
density in g / cm: 0.959,
- Fusian index, load 5 kg, I5: 2.7,
- Fusian index, load 21.6 kg, I21.6: 35.4,
Polydispersity I21.6 / I5: 13.1.

A2 TEST
This test was carried out with a catalytic composition CA2 prepared in the same way as the composition
CA1, with the difference that, for the A1 test, the suspension SA1 was used 8 days after its preparation, to obtain the CA1 composition, whereas in the A2 test, the SA2 suspension was stored for two months .

 Polymerization of ethylene was carried out under the same conditions as for test A1.

The results of the polymerization are as follows @
polyethylene mass obtained: 257.5 g,
- productivity: 65550gPE / gTi,
-% weight of waxes obtained. : e, 34,
density in g / cm 3: 0.959,
- melt index, 5 kg load, I5 s 2,7,
- melt index, load 21.6 kg, I21.6: 33.1,
polydispersity I21.6 / I5: 12.3
This test makes it possible to observe that the suspension SA 2 obtained is very stable and makes it possible to prepare catalytic compositions giving reproducible results over time.

TEST B
Preparation of the catalytic composition CB 27.7 milliliters of a solution of isoprenylaluminum in hexane containing 20.47 millimoles of IPRA and 40.94 millimoles of TiCl 4 are reacted at 0 ° C. under an inert atmosphere. and 40.94 millimoles of 4,4-dimethylpentene-1.

The resulting product is diluted with 220 milliliters of IPRA solution in hexane containing 2.5 milligrams of IPRA per liter. We thus obtain the suspension
SB.

In a thermostatically controlled reactor with a capacity of one liter, equipped with a feed on hydrogen and a supply of ethylene, is introduced 520 milliliters of dry hexane containing 0.52 milliliters of the suspension.
SB, 0.081 milliatome of titanium, and 1.21 millimole of IPRA. The titanium aluminum ratio is therefore close to 15.

 The reactor is maintained at 20 ° C. during this introduction, the reactor being flushed with a stream of nitrogen.

 The catalytic composition CB is thus obtained.

Polymerization of ethylene using the
catalytic composition CB
The polymerization is carried out in the same way as with the catalytic composition CT.

The results of the polymerization are as follows:
polyethylene mass obtained t 167,389
- productivity 1 43118gPE / gTi,
-% by weight of waxes obtained t 0.39,
- density in g / om3-s 0.960,
- melt index, load 5 kg, 15 s 2,2,
melt index, Charge 21.6I21.6: 25.8,
polydispersity I21.6 / I5: 11.7.

TEST C
Preparation of the CC catalytic composition
27.7 milliliters of a solution of IPRA in hexane containing 20.47 millimoles of IPRA, 40.94 millimoles of TiCl4 and 40.94 millimoles of butene-1 were reacted with OOC under an inert atmosphere. The product obtained is diluted with 213 milliliters of a solution of IPRA in hexane containing 2.5 millimoles of IPRA per liter. This gives the SC suspension.

In a thermostated reactor, of a capacity of one liter, equipped with a hydrogen supply and an ethylene feed, is introduced 520 milliliters of dry hexane containing 0.42 milliliters of the suspension.
SC, 0.081 milliatome of titanium and 1.21 millimole of IPRA. The titanium aluminum ratio is therefore close to 15.

 The reactor is maintained at 20 ° C. during this introduction, the reactor being flushed with a stream of nitrogen.

 The catalytic composition CC is thus obtained.

Polymerization of the ethylene using the
CC catalytic composition
The polymerization is carried out in the same way as with the catalytic composition CT.

The results of polymerization are as follows:
polyethylene mass obtained: 140.1 g,
- productivity: 36116 gPE / gTi,
-% by weight of waxes obtained 0.53,
density in g / cm 3: 0.959,
- melt index, 5 kg load, I5: 2.5,
- melt index, Charge 21.6 kg, I21.6: 29.9,
polydispersity I21.6 / I5: 12.0.

TEST A 3
Preparation of the CA3 catalytic composition
27.7 milliliters of a solution of IPRA in hexane containing 20.47 millimoles of IPRA, 40.94 millimoles of TiCl 4 and 40.94 millimoles of hexene-1 under a pressure of 25.7 mmoles are reacted at 0 ° C. hydrogen, the total pressure being 105 Pascals absolute.

 The product obtained is diluted with 210 milliliters of a solution of IPRA in hexane containing 2.5 millimoles of IPRA per liter.

 The suspension SA3 is thus obtained.

 In a thermostatically controlled reactor with a capacity of one liter, equipped with a hydrogen feed and with an ethylene feed, 530 milliliters of dry hexane containing 0.58 milliliters of the SA.sub.2.sup. milliatome of titanium and 1.24 millimole of IPRA. The titanium aluminum ratio is therefore close to 15.

 The reactor is maintained at 200 ° C. during this introduction, the reactor being flushed with a stream of nitrogen.

 The catalytic composition CA3 is thus obtained.

Polymerization of ethylene using the catalytic CA3 composition.

 The polymerization is carried out in the same way as with the catalytic composition CT.

The results of the polymerization are as follows
polyethylene mass obtained 209 g,
- productivity: 53651 gPE / gTi,
-% by weight of wax obtained: 0.36,
density in g / cm 3: 0.960,
melting index, load 5 kg I s 2.9,
- melt index, load 21.6 kg, I21.6: 34.4,
polydispersity I21.6 / I5: 11.9.

A4 TEST
Preparation of the CA4 catalytic composition
A suspension SA4 identical to the suspension SA3 of Test A3 is prepared.

In a thermostatically controlled reactor with a capacity of one liter, equipped with a hydrogen supply and an ethylene feed, 495 milliliters of dry hexane containing 0.56 milliliters of the suspension are introduced.
SA4, 0.079 milliatom of titanium and 0.392 millimole of IPRA. The reactor is maintained at 20 ° C. during this introduction.

 The pressure in the reactor is raised to 3.6 × 10 5 Pascals absolute, by introducing hydrogen at 20 ° C. The reactor is then brought to a temperature of 60 ° C. for one hour.

 The temperature of the reactor is then raised to 80 ° C.

Twenty milliliters of hexane containing 0.599 milligrams of IPRA is added.

 The catalytic composition CA4 is thus obtained.

Polymerization of ethylene using the
catalytic composition CA4
The polymerization is carried out in the same way as with the catalytic composition CT.

The results of the polymerization are as follows:
polyethylene mass obtained o 172.4 g,
- productivity s 45558
PE @@,
-% by weight of wax obtained: 0.36,
density in g / cm 3: 0.958,
- melt index, load 5 kg, I5 s 0.7,
- melt index, chargo 21.6 kg, I21.6: 11.5
polydispersity I21.6 / I5: 16.4,
TEST A5
Preparation of the CA5 catalytic composition
A suspension SA5 identical to suspension SA1 of test A1 is prepared.

In a thermostated reactor with a capacity of one liter, equipped with a hydrogen supply and an ethylene feed, 495 milliliters of dry hexane containing 0.33 milliliters of the suspension is introduced.
SA1, 0.082 milliateme of titanium and 0.611 millimole of IPRA. The reactor is maintained at 20 ° C during this introduction.

 The pressure in the reactor is raised to 3.6 × 10 5 Pascals absolute, by introducing hydrogen at 20 ° C.

The reactor is then heated to the temperature of 8 ° C for one hour.

 25 milliliters of hexane containing 0.618 millimoles of IPRA are added.

 The catalytic composition CA5 is thus obtained.

Polymerization of ethylene using the
catalytic composition CA5
The polymerization is carried out in the same way as with the catalytic composition CT.

The results of the polymerization are as follows:
polyethylene mass obtained: 151.0 g,
- productivity: 38451
-% by weight of wax obtained 2 0.20,
density in g / cm3 t 0.957,
melt index, load 5 kg, I5: 0.1, melt index, filler 21.6, kg I21.6: 1.3,
polydispersity I21.6 / I: 13.0.

15
TEST A6
The preparation of the catalytic composition CA6 is identical to that of the CA5 composition, unlike the hydrogen treatment is carried out at 70 C instead of 800C.

The polymerization of ethylene is carried out in the same way and the results are as follows:
polyethylene mass obtained 180.9 g,
- Productivity t 46056 in z by weight of wax obtained s 0.34,
- density in g / cm3 s 0.957,
- melt index, 5 kg load, I5 0.3,
- melt index, load 21.6 kg, 121.6 t 4.2,
- polydispersity @ I21.6 / I5
: 14.0,
TEST A7
The preparation of the catalytic composition CA7 is identical to that of the composition C5, with the difference that the treatment with hydrogen is carried out at 60 [deg.] C. instead of 80 [deg.] C.

The polymerization of methylene is carried out in the same way and the results are as follows:
polyethylene mass obtained: 224.2 g,
- productivity s 57084
-% by weight of wax obtained s 0.27,
density in g / cm 3: 0.957,
- melt index, filler 5 kg, I5 t 0.8, - melt index, filler 21.6 kg, I21.6 t 12.5, 21.0
polydispersity I 21.6 / 15: 15.6.

TEST A8
Preparation of the CA8 catalytic composition
11.6 milliliters of a 2.5 millimole solution per liter of IPRA in heptane are reacted at 7000 for 1 hour:
0.41 milliliters of the reaction product at 0 ° C. of Ti Cl4 and IPRA containing 0.08 milliliters of titanium,
- 50 microliters of hexene-1.

 In a thermostated reactor with a capacity of one liter, equipped with a hydrogen supply and an ethylene feed, is introduced the product of the previous reaction, 520 milliliters of hexane and 1.201 millimole of IPRA.

 The catalytic CA @ composition is thus obtained.

Polymerization of ethylene using CA8 catalytic composition
The polymerization is carried out in the same way as with the CT composition.

The results of the polymerization are as follows t
polyethylene mass obtained at 173.8 g,
- productivity s 45363
-% by weight of wax obtained t 0.28,
- density in g / cm3 t 0.958,
- melt index, 5 kg load, I5: 2,8,
- melt index, load 21.6 kg, I21.6: 30.7,
polydispersity I21.6 / I5: 11.0.

TEST A9
Preparation of the CA9 catalytic composition
The preparation of the CAg composition is identical to that of the CA8 composition, with the difference that the reaction:
- the product of the reaction of Ti Cl4 and IPRA
- Hexene-1 is carried out the presence of hydrogen at a total pressure of 105 Pascals absolute.

Polymerization of ethylene using the
catalytic composition CA9
The polymerization is carried out in the same way as with the CT composition.

The results of the polymerization are as follows
polyethylene mass obtained: 195.4 g,
- productivity: 50997 in z by weight of wax obtained: 0.26,
density in g / cm 3: 0.959,
- melt index, 5 kg load, I5: 2,4,
- melt index, load 21.6 kg, I21.6: 27.3,
polydispersity I21.6 / I: 11.4.

5
TEST A10
Preparation of the catalytic composition CA10
A suspension SA10 identical to suspension SA1 of test A1 is prepared.

In a thermostated reactor, with a capacity of one liter, equipped with a hydregene feed and an ethylene feed, is introduced 520 milliliters of dry hexane containing 0.32 milliliters of the suspension.
SA1, 0.079 milliliters of titanium, and 1.19 millimeters of triisobutylaluminum (TIBAL).

The titanium aluminum ratio is therefore close to 15. The reactor is maintained at 20 ° C. during this introduction, the reactor being flushed with a stream of nitrogen. The catalytic composition CA10 is thus obtained.

Polymerization of ethylene using the
catalytic composition CA10
The polymerization is carried out in the same way as with the catalytic composition CT, but the temperature is 90 ° C. and the pressure is 3.105 Pascals absolute.

The results of the polymerization are as follows:
polyethylene mass obtained 255.0 g,
productivity 2 67382
-% by weight of wax obtained, 46,
density in g / cm 3: 0.959, melt index, load 5 kg II 1.6,
induce melting, charge 21.6 kg, I21.6: 25,
polydispersity I21.6 / I: 15.2.

5
TEST A11
Preparation of the catalytic composition CA11
The catalytic composition CA11 is prepared in the same way as the CA1 composition, but with 0.04 milli titanium atom, ie a titanium aluminum ratio equal to 30.

Copolymerization of ethylene and butene-1 using
of the catalytic composition CA11
The reactor containing the catalytic composition CA 11 in solution in hexane is isolated.

 Hydrogen is then introduced into the reactor at 20 ° C. in a quantity such that the pressure inside the reactor is 3.6 × 10 5 Pases absolute. Ethylene and butene-1 are fed into the reactor in such quantities that the molar percentages of ethylene and butene-1, relative to each other, are respectively 97.5 and 2, 5 and that the pressure is 11.105 Pascals absolute when the temperature of the reactor is raised to 80 C.The ethylene and butene-1 copolymerize and continues to introduce ethylene and butene-1 into the reactor, so to maintain the pressure inside the reactor at 11.105 absolute Pascals and the composition of the gas phase constant for the duration of the copolymerization, which is fixed at 90 minutes.

 The polymerization is stopped by stopping the introduction of ethylene and butene-1 into the reactor, rapidly lowering the temperature to 200C and introducing into the reactor methanol containing hydrochloric acid.

The results of the copolymerization are as follows
- mass of copolymer obtained t 191.8 g,
- productivity s 100094
-% by weight of wax obtained i 0.47,
density in g / cm3 t 0.940,
- melt index, 5 kg load, I5: 7.7,
- melt index, load 21.6 kg, I21.6 t 71s
polydispersity I21.6 / I5: 9.2.

The results of the various tests are summarized in
Table below: TABLE

RESULTS <SEP> FROM <SEP><SEP> POLYMERIZATION <SEP> NOTES
<tb> TEST <SEP> CATALYST <SEP> Yield <SEP> Productivity <SEP>% <SEP> at <SEP> Weight <SEP> Mass <SEP> Indexes <SEP> of <SEP> Polydisen <SEP> g <SEP > gPE / gTi <SEP> of <SEP> waxes <SEP> volu <SEP> fusion <SEP> persity
<tb> mique
<tb> in
<tb> g / cm3 <SEP> I5 <SEP> I21.6
<tb> T <SEP> Ct <SEP> 128.9 <SEP> 32813 <SEP> 0.31 <SEP> 0.960 <SEP> 2.5 <SEP> 21.6 <SEP> 10.4 <SEP> Not <SEP> of use
<tb> olefin
<tb> when <SEP> of <SEP> the <SEP> preparation
<tb> A1 <SEP> CA1 <SEP> 239.4 <SEP> 60951 <SEP> 0.33 <SEP> 0.959 <SEP> 2.7 <SEP> 35.4 <SEP> 13.1 <SEP> Use <SEP> of hexene-1 <SEP> at <SEP> course
<tb> of <SEP> the <SEP> 1st <SEP> step
<tb> A2 <SEP> CA2 <SEP> 257.5 <SEP> 65550 <SEP> 0.34 <SEP> 0.959 <SEP> 2.7 <SEP> 33.1 <SEP> 12.3 <SEP> Use <SEP> of hexene-1 <SEP> at <SEP> course <SEP> of
<tb> the <SEP> 1st <SEP> step <SEP> and
<tb><SEP> storage of the <SEP> product <SEP> obtained <SEP> after
<tb> the <SEP> 1st <SEP> stage
<tb> during <SEP> 2 <SEP> months
<tb> B <SEP> CB <SEP> 167.3 <SEP> 43118 <SEP> 0.39 <SEP> 0.960 <SEP> 2.2 <SEP> 25.8 <SEP> 11.7 <SEP> Using <SEP> of
<tb> dimethyl-4,4 <SEP> pentene-1 <SEP> at <SEP> course <SEP> from
<tb> the <SEP> 1st <SEP> stage
<tb> TASLEAU (continued 1)

RESULTS <SEP> FROM <SEP><SEP> POLYMERIZATION <SEP> NOTES
<tb> TEST <SEP> CATALYST <SEP> Yield <SEP> Productivity <SEP>% <SEP> in <SEP> weight <SEP> Masso <SEP> Index <SEP> of <SEP> Polydisen <SEP> g <SEP > gPE / gTi <SEP> of <SEP> waxes <SEP> volu- <SEP> fusion <SEP> persity
<tb> mique
<tb> in
<tb> g / cm3 <SEP> I5 <SEP> I21.6
<tb> C <SEP> CC <SEP> 140.1 <SEP> 36116 <SEP> 0.53 <SEP> 0.959 <SEP> 2.5 <SEP> 29.9 <SEP> 12.0 <SEP> Using <SEP> of
<tb> butene-1 <SEP> at <SEP> course
<tb> of <SEP> the <SEP> 1st <SEP> step
<tb> A3 <SEP> CA3 <SEP> 209 <SEQ> 53651 <SEP> 0.36 <SEP> 0.960 <SEP> 2.9 <SEP> 34.4 <SEP> 11.9 <SEP> Using <SEP > from hexene-1 <SEP> to <SEP> course <SEP> from
<tb> the <SEP> 1st <SEP> step, <SEP> in
<tb> presence <SEP> of hydrogen
<tb> A4 <SEP> CA4 <SEP> 172.4 <SEP> 45558 <SEP> 0.36 <SEP> 0.958 <SEP> 0.7 <SEP> 11.5 <SEP> 16.4 <SEP> Using <SEP> of hexene-1 <SEP> to <SEP> of <SEP> of
<tb> the <SEP> 1st <SEP> step, <SEP> in
<tb> presence <SEP> of hydrogen, <SEP> but <SEP> treatment <SEP> at <SEP> hydrogen <SEP> at <SEP> more <SEP> at
<tb> course <SEP> from <SEP> la
<tb> second <SEP> step
<tb> TABLE (snite 2)

RESULTS <SEP> FROM <SEP><SEP> POLYMERIZATION <SEP> NOTES
<tb> TEST <SEP> CATALYST <SEP> Yield <SEP> Productivity <SEP>% <SEP> in <SEP> times <SEP> Mass <SEP> Indie <SEP> of <SEP> Polydisen <SEP> g <SEP > gPE / gTi <SEP> of <SEP> waxes <SEP> volu- <SEP> fusion <SEP> persity
<tb> mique
<tb> on <SEP> I5 <SEP> I21,6
<tb> g / cm3
<tb> A5 <SEP> CA5 <SEP> 151.0 <SEP> 38451 <SEP> 0.20 <SEP> 0.957 <SEP> 0.1 <SEP> 1.3 <SEP> 13.0 <SEP> Using <SEP> of hexene-1 <SEP> at <SEP> course <SEP> of
<tb> the <SEP> 1st <SEP> step <SEP> and
<tb> treatment <SEP> to <SEP> hydrogen <SEP> to <SEP> 80 C <SEP> to
<tb> course <SEP> from <SEP> la
<tb> second <SEP> step
<tb> A6 <SEP> CA6 <SEP> 180.9 <SEP> 46056 <SEP> 0.34 <SEP> 0.957 <SEP> 0.3 <SEP> 4.2 <SEW> 14.0 <SEP> Use <SEP> of hexene-1 <SEP> at <SEP> course <SEP> of
<tb> the <SEP> 1st <SEP> step <SEP> and
<tb> treatment <SEP> at <SEP> hydrogen <SEP> at <SEP> 70 C <SEP> at
<tb> course <SEP> of <SEP> the <SEP> second <SEP> step,
<tb> A7 <SEP> CA7 <SEP> 224.2 <SEP> 57084 <SEP> 0.27 <SEP> 0.957 <SEP> 0.8 <SEP> 12.5 <SEP> 15.6 <SEP> Using <SEP> of hexene-1 <SEP> at <SEP> course <SEP> of
<tb> the <SEP> 1st <SEP> step <SEP> and
<tb> treatment <SEP> to <SEP> hydrogen <SEP> to <SEP> 60 C <SEP> to
<tb> course <SEP> of <SEP> the <SEP> seconse <SEP> step,
<tb> TABLE (Continued 3)

RESULTS <SEP> FROM <SEP><SEP> POLYMERIZATION
<tb> TEST <SEP> CATALYST <SEP> Yield <SEP> Productivity <SEP>% <SEP> in <SEP> weight <SEP> Mass <SEP> Index <SEP> of <SEP> Polydisen <SEP> g <SEP > gPE / gTi <SEP> of <SEP> waxes <SEP> volu- <SEP> fusion <SEP> persity
<tb> mique <SEP> NOTES
<tb> in <SEP> I5 <SEP> I21,6
<tb> g / cm3
<tb> Using <SEP> Hexes
A8 <SEP> CA8 <SEP> 173.8 <SEP> 45363 <SEP> 0.28 <SEP> 0.958 <SEP> 2.8 <SEP> 30.7 <SEP> 11.0 <SEP> ne-1 <SEP> between <SEP> the <SEP> 1st
<tb> and <SEP> the <SEP> 2nd <SEP> step.
<Tb>

<SEP> use of hexene-1 <SEP> between <SEP><SEP> 1st
<tb> A9 <SEP> CA9 <SEP> 195.4 <SEP> 50997 <SEP> 0.26 <SEP> 0.959 <SEP> 2.4 <SEP> 27.3 <SE> 11.4 <SEP> and <SEP> the <SEP> 2nd <SEP> step,
<tb> in <SEP> presence <SEP> of hydrogen.
<Tb>

Same <SEP> test <SEP> as <SEP> Al,
<tb> but <SEP> use
<tb> A10 <SEP> CA10 <SEP> 255.0 <SEP> 67382 <SEP> 0.46 <SEP> 0.959 <SEP> 1.6 <SEP> 25 <SEP> 15.2 <SEP> from <SEP > TIBAL <SEP> at <SEP> course
<tb> of <SEP> the <SEP> second
<tb> step.
<Tb>

Same <SEP> test <SEP> as <SEP> Al,
<tb> but <SEP> copolymerized
A11 <SEP> CA11 <SEP> 191.8 <SEP> 100094 <SEP> 0.47 <SEP> 0.940 <SEP> 7.7 <SEP> 71 <SEP> 9.2
<tb> tion <SEP> of ethylene <SEP> and
<tb><SEP> butene-1.
<Tb>

 This table shows that the process according to the invention makes it possible to prepare catalytic compositions from which it is possible to obtain polyethylene of higher polydispersity than that of the Temein T test, with higher yields (see Tests A1 to A10). as well as ethylene-butene-1 copolymer (Test A11) of low density (0.940 g / cm3) and low polydispersity (9.2), suitable for the production of films.

 In addition, (see Test A10), it is possible to use, during the process, the triiobutylaluminum (TIBAL) at a cost significantly lower than isoprenylaluminum (IPRA), which is another advantage of the process according to the invention. 'invention.

Claims (15)

 1. A process for preparing a catalyst composition for the polymerization of olefins, said process comprising:  1) in a first step, to react:  at least one compound A of an element selected from the group consisting of the elements of groups IVA to VIA of the periodic table of elements, said element being found in said compound A at a degree of oxidation greater than the oxidation degree; minimum of that element, with  at least one organometallic compound B of an element selected from the group consisting of the elements of groups I to III of the periodic table of elements;  2) in a second step, to add, in at least one operation, to the reaction product of the first step, at least one compound B 'chosen in the same family as that of compound B, said compound B' being identical or differ from compound B,  said process being characterized in that during and / or after the first step, and / or during and / or after the second step, an olefin is reacted on the products in the presence.  2. A process according to claim 1, characterized in that the amount of olefin reacting on the products in the presence is preferably less than 10 millimoles and, more preferably, between 0.01 and 5 milli moles, per milliatom of the element of groups IVA to VIA present.  3. A process according to one of claims 1 and 2, characterized in that the olefin is reacted during the first step.  4. A process according to one of claims 1 and 2, characterized in that the olefin is reacted after the first step and before the second step.  5. A process according to one of claims 1 to 4, characterized in that, during the preparation of the catalytic composition, is carried out at least one treatment with hydrogen.  6. A process according to claim 5, characterized in that a treatment with hydregene is carried out during the first step.  7. A process according to claim 6, characterized in that the second step is carried out in two operations, and in that, between the two operations, is carried out additional treatment with hydrogen.  8. A process according to claim 6, characterized in that the second step is carried out in two operations and in that, between the two operations, is carried out the treatment with hydrogen.  9. A process according to claim 4, characterized in that, simultaneously with the reaction of the olefin on the product obtained at the end of the first step is carried out treatment with hydrogen.  10. A process according to one of claims 1 to 9, characterized in that the olefin is selected from the group consisting of butene-1, dimethyl-4,4-pentene-1 and hexene-1.  11. A process according to one of claims 1 to 10, characterized in that the compound A is titanium tetrachloride,  12. A process according to one of claims 1 to 11, characterized in that the compound B is selected from the group consisting of isoprenylaluminum, triisobutyl aluminum, trioctylaluminium and diethylzinc.  13.- Preceded according to one of claims 1 to 12, characterized in that the compound B is isopronylaluminium.  14. Catalytic compositions prepared by a process according to one of claims 1 to 13.  15.- Application of the catalyst compositions according to claim 14 to the polymerization of olefins and the copolymerization of olefins, in order to obtain controlled polydispersity products and density.