FI117557B - A process for polymerizing olefins - Google Patents

Abstract

Olefins are polymerised in contact with a catalyst system contg. (a) a solid catalytic complex based on Mg, a transition metal and a halogen, obtd. by (i) reacting (I) an oxygenated organo-Mg cpd. or a halogenated Mg cpd. with (II) an oxygenated organic cpd. or a halogenated cpd. of a transition metal of Gps. IVB or VB, to give a liq. complex, (ii) precipitating. the complex by means of a cpd. of formula AlRnX3-n, to give a solid catalytic complex, (iii) sepg. the solid complex, and (iv) treating the solid complex with a cpd. of formula AlRnX3-n, and (b) an organic cpd. of a metal of Gps. IA, IIA, IIB, IIIA or IVB. R = hydrocarbo gp.; X = halogen; n = less than 3.

Description

117557

This process relates to a process for the polymerization of olefins, more particularly to a process for the polymerization of olefins in the presence of a catalytic system comprising a solid catalytic complex comprising magnesium, transition metal and halogen, and an organometallic compound (cocatalyst).

U.S. Patent No. 4,588,704 relates to a process for the preparation of a catalyst for the polymerization of olefins, which is formed from a magnesium compound, a transition metal and an organoaluminum compound. EP-A-480375 relates to a process for the polymerization of an olefin using a catalyst which is likewise formed from the aforementioned compounds. According to these publications, the preparation of the catalytic complex comprises two separate treatments of the solid catalytic complex with the halogenated organoaluminum compound.

British Patent No. 1,464,909 discloses catalytic systems containing a magnesium, transition metal, and halogen-containing solid and a co-catalyst. In Example 1 of this patent, * ··. ethylene is added to triisobutylaluminum and solid catalyst; # · # In the presence of a lyser prepared by mixing * * · ** y 25 clubs of magnesium ethylate with tetrabenzyl titanium and * adding thereto a halogenated organoaluminum compound until a solid precipitate is obtained.

* · · * · * * The precipitate obtained is then separated.

Polyethylene obtained in the presence of this known solid catalyst has a low apparent density, which reduces the production capacity of the polyethylene silicone by the use of this solid catalyst.

It is an object of the invention to eliminate this disadvantage and to provide a novel process for the preparation of polyolefins having a higher apparent density.

2 117557

Therefore, the invention relates to a process for the polymerization of olefins comprising contacting at least one olefin with a catalytic system comprising: a) a solid catalytic complex containing magnesium, transition metal and halogen, and b) groups IA, IIA, IIB of the Periodic Table. , IIIA and IVA organometallic metal compounds; characterized in that said 10 solid catalytic complex (a) is prepared in a first step by reacting at least one magnesium compound selected from organic oxygen-containing magnesium compounds and halogenated magnesium compounds with at least one transition metal compound of Group IVB or VB-15 of the Periodic Table. selected from organic oxygen containing compounds and transition metal halogenated compounds until a liquid complex is obtained, and in a second step treating said liquid complex with a halogenated organoaluminum compound of the general formula AlRnX3-n where R is a hydrocarbon radical, X is halogen is less than •; .. j 3, whereupon the liquid complex precipitates into a solid cat · · · ·, lytic complex, and in the third step, the reaction · ·; [·. the solid catalytic complex precipitated from the mixture in a second step is separated, and the solid catalytic complex separated in the third step is treated in a fourth step with a halogenated organoaluminum compound of the general formula '£ • * »' *. is AlRnX3-n and recovering the solid catalytic complex without prepolymerizing it.

The first three steps of the preparation of the catalytic complex (a) are known. An essential feature of the invention. ···, the polymerization process is characterized by the use of a solid catalytic complex (a), the preparation of which requires a fourth step, which is finally dealt with at the end of the third step. separated solid catalytic complex by means of a halogenated organoaluminium compound which may be repeated several times as mentioned in the 3 117557. This further treatment with the halogenated organoaluminium compound is hereinafter referred to briefly as "post-treatment".

The post-treatment can be carried out by repeating the first treatment with the halogenated organoaluminium compound (second step), i.e. under the same reaction conditions (temperature, pressure, reagent addition rate, ...) and with the same halogenated organoaluminum compound (s) 10a. ) in the same quantities. Alternatively, the post-treatment may be carried out under other reaction conditions and / or other reagents and / or in varying amounts. In the event that the post-treatment is repeated several times, the same halogenated organo-15 aluminum compound or different organo-aluminum compounds may be used in each of these additional treatments. The post-treatment can be repeated several times, for example 1-2 times. Usually it is not repeated more than once.

It is preferable to carry out only one post-treatment so that in the fourth step there is only one treatment with the halogenated organoaluminum compound. In addition, it is better to post-treat with a halogenated organoaluminum compound which is the same as that used in the second step and the other. reaction conditions of the step.

• · • *

The total amount of halogenated organoaluminium compound used in the post-treatment (s) may be less, the same or greater than that used in the second step, and it will vary the molecular weight distribution of the polyolefin to the desired • · · *. · * according to the hair. It is usually at least 0.1 mole aluminum per mole of transition metal used, more particularly 30 at least 0.2 moles, values of at least 0.5 being preferred; : '** · It is often up to 40 moles of aluminum per mole • · * Transition metal used, preferably up to 20 moles, values up to 10 moles are most preferred.

In the process of the invention, the post-treatment i :; The purpose is to continue the reaction which began in the second step, where the first treatment is with a halogenated * ··· 117557 organometallic compound. More specifically, the purpose of the second step reaction is to reduce the valence of the transition metal in the transition metal of the liquid complex. It is intended to simultaneously halogenate the magnesium compound and / or the transition metal compound in the liquid complex, i.e. to replace the alkoxy groups present in the magnesium compound and / or the transition metal compound with halogens. Reduction and possible halogenation thus result in the precipitation of the liquid complex obtained at the end of the first step into a solid catalytic complex. The reduction and the possible halogenation are carried out simultaneously by means of a halogenated organoaluminum compound, which thus acts as a halogenating reductant which causes precipitation of the solid catalytic complex.

At the end of the first treatment (second step) with a halogenated organoaluminum compound, a solid catalytic complex containing a homogeneous precipitate (components co-precipitated from a liquid complex), a mixture of magnesium halide, 20 transition metal halides and partially reduced and / or partially halogenated compound is recovered. These are chemically bound complexes, products of chemical reactions, and not complexes due to mixing or adsorption phenomena. In fact, it is impossible to dissociate any component of these complexes using purely physical separation techniques.

♦ · · · * · ί ϊ The purpose of the characterization post-treatment is to continue the reduction of the V: solid complex and possible halogenation. The degree of reduction obtained and, if desired, the degree of halogenation is determined by a number of additional treatments, the amount and nature of the halogenated organoaluminum compound used. by.

* · · * .. After treatment, a solid-catalyzed complex similar in character to the one described above (chemically bonded complex) is recovered, but containing, at least in part, reduced and / or partially halogenated compounds.

The astonishing effect of the present invention is that with the same total amount of halogenated organoaluminum compound used and separation of the treatment by such compound into several (at least 2) separate and sequential treatments, a solid catalytic complex (a) resulting in apparent specific gravity for the production of larger polyolefins.

The post-treatment with the halogenated organoaluminum compound (just like the first treatment in the second step) can be carried out in any known suitable manner and preferably by the stepwise addition of the halogenated organoaluminum compound to the solid catalyst complex derived from the previous step (or step step one). Therefore, the organoaluminum compound may be added neat to the solid catalytic complex (or liquid complex) or as a solution in a solvent such as liquid aliphatic, cycloaliphatic and aromatic hydrocarbons. The best diluents f are hydrocarbons containing up to 20 carbon atoms, and especially straight chain alkanes (such as n-butane, ***, *** ni, n-hexane and n-heptane) or branched alkanes. 25 (such as isobutane, isopentane, isooctane) or cycloalkanes (such as cyclopentane and cyclohexane). Good results • · • · · ί .:: obtained with straight chain alkanes. Hexane is the best.

The organoaluminum compounds used in the post-treatment (such as those used in the second step) are preferably selected from those having the formula AlRnX3-n / if- hydrocarbon radical containing up to 20 · ♦ ·, t. carbon atoms and preferably up to 6 carbon atoms, and mixtures of these. Good results are obtained when R is an alkyl radical (linear or branched), a cycloalkyl, an arylalkyl, an aryl and an alkylaryl radical. The best of · ·; ***. results are obtained when R represents straight-chain or

«M

6 117557 suspended alkyl radicals. Generally, X is selected from fluorine, chlorine, bromine or iodine. Chlorine is particularly well suited.

Preferably n does not exceed 1.5, especially not l. As examples of the halogenated organoaluminum compound useful may be mentioned aluminum trichloride [AlCl 3], ethylaluminum dichloride [Al (C 2 H 5) Cl 2], ethylaluminum sesquichloride [Al 2 (C 2 H 5) 3 Cl 3] and diethylaluminum (H 2) 2).

Ethyl aluminum dichloride or isobutyl aluminum dichloride is preferred. Isobutylaluminium dichloride is particularly good in that it can be used to prepare solid catalytic complexes which produce polymers with a finer particle size distribution (polymer particle size) than polymers obtained with other halogenated organoaluminum compounds. In particular, the formation of fine polymer particles is avoided as compared to particles obtained with other halogenated organoaluminum compounds.

The temperature at which the post-treatment (as well as the second step) is carried out is preferably lower than the boiling point of the halogenated organoaluminum compound under normal pressure. It is generally at least -20 ° C, in particular at least 0 ° C. temperatures of at least 20 ° C are preferred. Temperatures often do not exceed 150 ° C, especially not 100 ° C, with temperatures up to 80 ° C being the most common.

• ·

The pressure at which the post-treatment is performed (and the * * * *** / 25 second stage) is not a critical factor. For practical reasons, things usually work under normal pressure. Reagent addition rate: generally selected so as not to cause the reaction mixture% • »·. h V: Sudden heating due to possible self-acceleration of reaction. The reaction mixture is generally stirred: 30 to improve its homogeneity during the step or treatment.

• · ·

In a first preferred embodiment of the invention, f * * *; * | # * The second step (i.e., the precipitation step) of the preparation of the solid catalytic complex is immediately followed by a maturation step (three: V; 35 pre-matte step) which is intended to be Φ ·; "* · manufactures solid catalytic complexes having.

··· 7 - 117557 improved resistance to uncontrolled polymerization tendency. Further, maturation can remove fine particles which are not easily decanted and therefore difficult to separate from the second stage reaction mixture.

5 Maturation is generally carried out at the same or higher temperature than in the second stage. Its duration is not critical and can generally range from 5 minutes to 12 hours, preferably at least 0.5 hours.

In another preferred embodiment of the invention, the third step of preparing the solid catalytic complex (i.e., the step of separating the solid complex) is immediately followed by washing (preceding the fourth step) to remove excess reagents and any byproducts that may arise from the precipitated catalytic complex may still be. Washing can be used to modify the properties of the solid catalytic complex, and in particular the response of the solid catalytic complex to molecular weight regulators such as hydrogen. Therefore, washing can control the molecular weight distribution and the oligomer content of the resulting polymers obtained with a solid Λ '| , J #>; catalytic complex. Therefore, washing can also surprisingly achieve the same results as air washing with less halogenated organoaluminum compounds in the fourth step. Preferably, maturation, as described above, precedes the third step, t ·, followed by washing. Any inert diluent and, for example, alkanes and cycloalkanes which may be used for this washing may be used. containing up to 20 carbon atoms.

: **: 30 Hexane and isobutane are fine. After washing fixed • · ·; ***. For example, the catalytic complex may be dried for example y • · · .1. an inert gas stream, preferably dry, such as nitrogen • · ** | * using the power. (• · * ··· * According to a third preferred embodiment of the invention, 35 post-treatments, each post-treatment if necessary, are followed by a maturation step which can be carried out under the same heat conditions.

Ml 8 117557

In patients and for the same time as described above and / or with the same washing as described above. When maturation and washing are performed, it is better to perform maturation before washing.

As described above, the preparation of the solid catalytic complex (a) used in the polymerization process of the invention comprises three separate and sequential steps known per se, namely the first step of forming the liquid complex, the second step precipitating the liquid complex into the solid complex, and the third step. distinction, each of these steps is known per se.

The solid catalytic complex used in the process of the invention is not prepolymerized.

The first known step is the preparation of a liquid complex by reaction of a magnesium compound with a transition metal compound. Of course, several different magnesium compounds can be used simultaneously. In addition, several different transition metal compounds or several compounds having different transition metal may be used simultaneously. The reaction of the first step can be carried out by any suitable method known in the art, as long as it provides a liquid complex. When the magnesium compound * ·, *** and / or the transition metal compound are liquid under the reaction conditions, it is desirable to carry out the reaction by simple mixing of the reagents without solvent or plates. Menni. However, the reaction may be carried out in the presence of a diluent when the amount of liquid in the reaction mixture is insufficient to complete the reaction or when two reactants are solid under the reaction conditions. Dilute- ··· · ** ·. In general, one is able to dissolve at least one of the reagents, and in particular one of the solvents described above.

»» · »« * ··· * The amount of transition metal used is determined by the amount of 35 magnesium compounds used. It may vary • ·. ***. greatly. Generally, it is at least 0.01 mole of transition metal per mole of magnesium compound, especially at least 0.02 mole, the values of at least 0.05 being the best. Typically, the amount is up to 20 moles per mole of transition metal compound in the transition metal compound 15, more particularly up to 10 moles, values up to 5 moles are preferred.

The temperature used in the first step of the preparation of the solid catalytic complex in the presence of the magnesium compound and the transition metal depends on the nature of the reagents and is preferably lower than the decomposition temperature of the reagents and the liquid complex obtained after the reaction. It is generally at least -20 ° C, especially at least 0 ° C, temperatures of at least 20 ° C being the most common.

The temperature is usually up to 200 ° C, in particular up to 180 ° C, temperatures up to 150 ° C are preferred, for example about 140 ° C. '

The duration of the first step in the preparation of the solid catalytic complex depends on the nature of the reagents and the reaction conditions and is preferably long enough to allow complete reaction between the reagents.

, The duration can generally range from 10 minutes to 20 hours, more specifically from 2 hours to 15 hours, for example 4-10 hours.

The pressure at which the first-stage reaction is performed and the rate at which reagents are added are generally not critical factors. For practical reasons, work is usually carried out at normal pressure, the addition rate being generally chosen so that r: *; * ♦ does not cause a sudden heating of the reaction mixture, i; Due to the possible self - acceleration of the reaction,. 30 yrs. The reaction mixture is generally stirred so that its homo · · φ, ···, genotype is improved during the reaction. The reaction may be · · * “continuous or non-continuous.

··· * At the end of the first stage of the preparation of the solid catalytic complex, the liquid complex of magnesium compound and transition metal compound is recovered,

which may be used as such in the following formula or which may be stored in a diluent,

which is preferably inert to recover it | si intact and to be used in the presence of diluent i5. Aliphatic or cycloaliphatic hydrocarbons containing * preferably up to 20 carbon atoms, such as alkanes such as isobutane, pentane, hexane, heptane or cyclohexane or mixtures thereof, are most often selected as diluents. Hexane 10 is particularly suitable.

Oxygen-containing organic compounds and halogenated magnesium compounds are selected as the magnesium compound. -

Oxygen-containing organic magnesium compound refers to all compounds wherein the organic radical is bound to magnesium by oxygen, i.e., all compounds containing at least i

a single bond magnesium-oxygen-organic radical through a magnesium atom. Organic radicals bound to magnesium via oxygen are generally selected from J

radicals containing up to 20 carbon atoms and especially those containing up to * * 10 carbon atoms. Good results have been obtained when these radicals contain from 2 to 6 carbon atoms. These radicals may be saturated or unsaturated, straight-chain, *: * branched or cyclic. They are preferably selected from the group consisting of carbonyl and especially alkyl radicals (straight-chain or branched), alkenyl, aryl, cycloalkyl, arylalkyl, alkylaryl, acyl radicals. 30 of cabbages and their substituted derivatives.

· ·

Organic magnesium compounds containing oxygen may contain other radicals in addition to the organic radicals bound to magnesium by oxygen. These other radicals are preferably -OH-, - (SO4) 1/2, ··· '35 -NO3, - (PO4) 1/3, - (CO3) 1/2 and -C104. 11 117557 may also be organic radicals directly bonded to magnesium by carbon.

Useful oxygen-containing organic magnesium compounds include alkoxides (such as> 5 ethylate and cyclohexanolate), alkyl alkoxides (such as ethyl ethyl acetate), hydroxyalkoxides (such as hydroxymethylate), phenoxides (such as naphthenates), carboxylates, benzoate). It may also be oxygen-containing nitrogen-containing piperidine organic compounds, i.e. compounds containing magnesium-oxygen-nitrogen-organic radical linking moieties (such as oximates, especially butyloxymate, salts of hydroxylamine acids, especially N-nitroso-N-phenylhydroxylamine), chelates, i.e., 15 oxygen-containing organic compounds in which magnesium has at least one normal bonding moiety magnesium-oxygen-organic radical and at least one magnesium coordinate bond forming a heterocycle containing magnesium (such as enolates, especially acetyl 20-acetonate) , silanoates, i.e. compounds containing bonding sequences of magnesium-oxygen-silicon hydrocarbon (such as triphenylsilanoate). Examples include organic oxygen-containing magnesium compounds which contain • * ***** contain a variety of organic radicals (such as · · · 25 magnesium methoxyethylate), alkoxide and phenoxide complexes of magnesium and other metals (such as Mg [Al-* * ·: · (0R) 4] 2) and these two or more as defined above

::: Oxygen-containing organic magnesium compounds A

* '· * Mixtures.

. 30 Halogenated magnesium compound means • · *. * · *. all compounds containing at least one magnesium? ♦ · * · Si-halogen bond. The halogen may be fluorine, chlorine, bromine or iodine. Halogen is preferably chlorine.

• · · Λ: ... * Among the halogenated magnesium compounds can be *. *. *. Dihalides, preferably containing 12,17557 at most one water molecule per one dihalide molecule, complexed dihalides (such as MgCl2.6NH3 or MgCl2.6CH3OH), compounds containing magnesium in addition to a halogen bond, an organic radical bonded to magnesium by oxygen (such as Mg (OH) Cl or Mg (O-CH 3) Cl). They may also be compounds which, in addition to the magnesium-halogen linkage, contain hydrolysis products of magnesium-organic radical linkage (such as Mg (C 2 H 5) Cl), magnesium halide hydrates, however, these compounds also contain magnesium-halide linkages, containing halogenated and oxygen-containing magnesium compounds (such as MgCl 2 .MgO.- * H 2 O) and mixtures of these two or more halogenated magnesium compounds as defined above.

Of all the suitable magnesium compounds, those preferably containing no magnesium atoms other than magnesium-oxygen-organic radicals are used.

li-bonds and / or magnesium-halogen bonds and not mi-? other ties. The best results are obtained with organic oxygen-containing compounds, especially those containing only magnesium atoms per magnesium, oxygen-organic radical. Magnesium alkoxides are particularly good. The best results have been obtained with magnesium dialkoxides, especially magnesium diethylate. ...? Oxygen-containing organic compounds or transition-metal halogenated compounds are selected as the transition metal compound.

t · · · * · * · The transition metal oxygen-containing organic a - - 'ϊ * refers to all compounds in which the organic. The transition radical is bound to the transition metal by oxygen transfer, i.e., all compounds containing at least one transition metal-oxygen-organic radical per one transition metal atom. The organic * · · radicals are the same as defined above for the organic · * ·, magnesium compounds containing oxygen.

• a · a · aaa aa a * a a · '' 13 '117557

The transition metal is preferably selected from titanium, zirconium, hafnium and vanadium. Titanium and zirconium fit well. Titanium is particularly good. In the case of titanium, zirconium and hafnium, tetra-? 5 valent transition metal compounds because they are mostly liquid and in any case more and more soluble than transition metal compounds having a metal valence less than 4.

Useful organic oxygen-containing transition metal compounds may also contain transition metal-oxygen-transition metal bonds.

Organic oxygen-containing transition metal compounds? you may be represented by the general formula M0x (0R ') m_2x, where M represents the valence m of the bridging metal, R' represents an organic radical as defined above, and x is a number which is 0 <x <(m-1) / 2. It is preferable to use compounds wherein x is 0 <x <(m-2) / 2.

It will be appreciated that organic oxygen-containing transition metal compounds may contain a variety of different organic radicals.

Organic oxygen-containing transition metal compounds. among the alcohols, alkoxides (such as tl * ·. „* Ti (0-nC4H9) 4), phenoxides (such as Zr (OC6H5) 4), oxyalkoxides • ·" .'1! * ·· * (such as Hf0 (OC2h5) ) 2), fused alkoxides (such as Ti 2 O - 25 (O-Cl 3 H 7) 6), carboxylates (such as Zr (OOCCH 3) 4) and enolates * ... (such as hafnium acetylacetonate).

The transition metal halogenated compound refers to all compounds containing at least one transition metal-halogen bond. The halogen is the same as; j *; for halogenated magnesium compounds as defined above.

···. ···. Chlorine is the best, • · C '.' ••• if * * ·, v / mt Among the transition metal halogenated compounds |

• · · '. 'T

* · * * Halides, especially tetrahalides (such as TiCl4), complexed halides (such as ZrCl4-356NH3), complex and transition metal and alkali metal complexes (such as Na2TiCl6), oxides, may be mentioned. (such as HfO-

Cl 2) and haloalkoxides (such as Ti (OC 2 H 5) 2 Cl 2 or Zr (O 1 - 3 → 1)) ♦

It is obvious that several transition metal compounds can be used simultaneously. When it is desired to produce a high molecular weight polyolefin, it may be preferable to use various transition metal compounds, particularly the titanium compound and the zirconium compound.

Among all suitable transition metal compounds, those containing only transition metal-oxygen-organic radical linkages and / or transition metal-halogen linkages, and no other linkages, are preferably used. Best results have been obtained with transition metal oxygen-containing organic compounds, especially those containing only transition metal-oxygen-organic radical bonds. Alkoxides work well. The best results have been obtained with titanium or zirconium tetraalkoxides, especially titanium or zirconium tetrabutylate. i 1 *

Another known step, which is the (first) treatment of the halogenated organo, aluminum compound to precipitate a solid catalytic complex, the purpose of which is described above, is carried out under the same conditions as above for the post-treatment. was described in detail.

The amount of halogenated organoaluminum compound used in the second stage must be sufficient to precipitate as little solid catalytic complex as possible. . *. 30 which can be separated from the reaction mixture of the second step.

· · · * * *. ···, It is usually at least 0.5 moles per mole of aluminum »· * 1 * used transition metal, preferably at least 1 mole, # # * t * * *. * Values of at least 2 moles are most common , it is generally 5 · * * up to 50 moles of aluminum per spent transition metal • 11 · 5 · 5 · 1 · 117557 is, especially up to 30 moles, values of max.

20 moles are preferred. J

The solid complex precipitated during the second stage the nature of sin has already been described above.

In a third known step, the solid catalytic complex precipitated during the second step is separated off.

This separation may be carried out in any known suitable manner, for example by filtration or centrifugation.

In addition to the solid catalytic complex (a) containing magnesium, transition metal and halogen as described above, the polymer of the olefin of the invention is | the catalytic system used in the coupling process comprises a metal organometallic compound of groups IA, IIA, IIIA and IVA of the Periodic Table (b). The organometallic compound of lithium, magnesium, zinc, aluminum or tin can be selected as this organometallic compound which acts as an activator of the solid catalytic complex and is commonly referred to as the "cocatalyst". The best 20 results are obtained with organoaluminum compounds. |

The organometallic compounds may be used in their entirety. alkylated compounds containing up to 20% ···· *. / & • *.

carbon atoms and are linear or branched%, such as n-butyllithium, diethylmagnesium, diethylzinc, tetraethyltin, tetrabutyltin, and trialkylaluminium. Alkyl metal hydrides may also be used where the alkyl radicals also contain corf ί ϊ up to 20 carbon atoms, such as diisobutylaluminum hydride. rid and trimethyltin anhydride. Also suitable are metal .30 alkyl alkali halides containing alkyl radicals. also up to 20 carbon atoms, such as ethyl • aluminum.

Sesquichloride, diethylaluminum chloride and diisobutyl * • · · *. * * Aluminum chloride. Organo-aluminum compounds can also be used. · · · -Dists obtained by reacting trialkylaluminum 35 35 or dialkylaluminum hydrides containing up to 20 carbon atoms with radicals of up to 20 carbon atoms, with diolefins containing from 4 to 20 carbon atoms, and in particular f compounds known as isoprenylaluminum.

In general, trialkylaluminums are preferred, especially those having straight alkyl chains and containing up to 18 carbon atoms, in particular 2 to 8 carbon atoms. Triethylaluminium and triisobutylaluminium are preferred.

The total amount of organometallic compound used in the polymerization process of the invention can vary greatly. It is generally 0.02 to 50 mmol per liter of solvent, diluent or reaction vessel volume, and is preferably 0.2 to 2.5 mmol per liter.

The amount of solid catalytic complex (a) used in the polymerization process of the invention is determined by the concentration of the transition metal of said complex. It * is generally selected at a concentration of 0.001 to 2.5 and preferably 0.01 to 0.25 moles of transition metal per liter of% 20 solvent, diluent or reaction vessel volume. '

Total metal in organometallic compound. the molar ratio of the amount to the total amount of transition metal in the transition metal compound is usually at least '* ·' * · ** 1, especially at least 5, values of at least 10 being preferred.

* ·: 25 Ratios are usually up to 100, preferably up to 75, values up to 50 are recommended.

; In addition to the solid catalytic complex (a), the organometallic compound described in more detail above, according to the invention | The catalytic f. 30 system used in the 1-stage polymerization process may contain an electron donor. It is used ···. ···. Preferably immediately after the first preparation of the solid catalytic complex (a) • # • to obtain a liquid · · * *. * * Thus, the electron donor can be used either at any stage of the preparation of the solid catalyst-35 complex, but can be used after the preparation of the liquid complex, or directly in the polymerization step. - f hese.

In the first embodiment of the invention, where an electron donor is used, it is used in a solid catalyst

5). In a first variant of this embodiment, the liquid complex from the first step of preparing the solid catalytic complex (a) is treated with an electron donor. In another variation of this assay, the solid catalytic complex formed during the post-treatment with the halogenated organoaluminium compound, and preferably after any maturation and washing steps, is treated with electron donors (before the solid catalytic complex (a) is reacted with.

In the first embodiment (according to these two variants), the hand to be performed by means of electron donors

the processing may be carried out by any suitable means known in the art. The electron donor may be added neat to the 20 liquid complexes derived from the first I

or a solid catalytic complex which

is derived from the third or fourth stage, or

«>, * · * * As a solution in a solvent as described above.

The temperature at which electron donor treatment is carried out according to the first embodiment of the invention is ·· * * '*: * preferably lower than that of the electron donor and liquid

M ·· V

'· *; the decomposition temperatures of the complex. It is generally at least r,. ·; ·, -20 ° C, more particularly at least 0 ° C, values of at least 20 ° C being * '• · * most common. Temperatures are usually up to 30 150 ° C, especially up to 120 ° C, temperatures up to 100 ° C are recommended, for example up to 70 ° C.

Electron Donor Processing : ***: The duration in the first embodiment is usually 0.5 minutes- * · 35 hours to 5 hours, preferably 1 minute to 2 hours, e.g. ,>: 18 117557 chips from 5 minutes to 1 hour. The pressure at which the processing was done. ..

If not critical, the reaction is preferably carried out at normal pressure.

The amount of electron donor used in the first embodiment is usually at least 0.01 mole per mole of transition metal used, more particularly at least 0.02 mole, values of at least 0.05 being most preferred. The amount of electron donor used will often not exceed 50 moles per mole of transition metal used, preferably 10 moles to 20 moles, values of at least 5 moles being preferred. 0.2 to 12 moles are particularly suitable; very. f

The first embodiment, when using an electron donor in the step of preparing the solid catalytic complex (a), can not only increase the apparent specific density of the polyolefins obtained, but also reduce the oligomer content of the resulting polyolefins. In particular, the first variant can increase the activity of the solid catalytic complex in the polymerization and obtain a solid catalytic complex of? more sensitive to molecular weight regulators of polyolefins.

Another variation can also be used to modify the response of the solid i] catalytic complex to regulators of molecular weight of polyolefins (e.g., hydrogen) by varying the amount of electron donors used. In fact, it has been found that the greater the amount of electron donor used, the stronger the response of the solid catalytic complex to regulation. It follows that very different molecular weights and hence flow rates are obtained. 30 spectrum of polyolefins of very different denx.

• · * ^. ···. In another embodiment of the invention, electron donors are used during polymerization. This - ··· ·· '·> *. * * Second embodiment has proven to be particularly effective when the polymerization is carried out in the gas phase. In this embodiment, the electron donors can be added separately to the polymerization mixture at any time, preferably at the beginning of the polymerization. In this preferred embodiment, the electron donor may be added to the polymerization mixture mixed with the organometallic compound, the mixture prepared in advance 5. This mixture may be prepared simply by contacting the electron donor with the organometallic compound or by adding the electron donor, preferably by gradually adding the electron donor solution to the The electron donor is preferably added neat to the solution of the organometallic compound in the solvent as defined above.

In another embodiment, the amount of electron donation used is usually such that the molar ratio of the amount of organometallic compound used to the amount of electron donor used is at least 0.01, especially at least 0.05, values of at least 0.2 being most preferred.

The ratio of these amounts often does not exceed 100, preferably not 80, values of at least 60 are most preferred.

An advantage of the second embodiment is that it not only increases the apparent specific gravity of the polyolefins obtained, but it also increases the ac-.

«·« * ... · compactness in polymerization. It has proven to be especially • · ·, · | 25 preferred in the gas phase polymerization process *, which is generally characterized by limited heating: *; transmission capacity, since the kinetic profile of the solid catalytic complex *; * · lex has a significant induction time.

Electron donor in the present invention refers to organic compounds containing one or more • · *** atoms or groups of one or more atoms having ί one or more free electron pairs, such as f: oxygen, nitrogen, sulfur or groups containing these. *! *. 35 elements. Examples of electron donors that can be used are: • * · • * ♦ ·· · · · · · · 20 117557

used in the process of the invention are alcohols, phenols, ethers, ketones, aldehydes, organic

acids, esters of organic acids, halides of organic acids, amides of organic acids, amines, alkoxysilanes and nitriles.

As alcohols and phenols, for example, those containing up to 18 carbon atoms such as methyl alcohol, n-butyl alcohol, cyclohexyl alcohol, stearyl alcohol and phenol may be used. As examples of ethers-10, those containing from 2 to 20 carbon atoms, such as isoamyl ether, may be mentioned. Ketones which are generally useful are those containing from 3 to 18 carbon atoms, such as methyl ethyl ketone and acetophenone.

The aldehydes commonly used are those containing 2 to 15 carbon atoms such as octyl aldehyde and benzaldehyde. Examples of organic acids are those containing up to 24 carbon atoms, such as butyric acid and methoxybenzoic acid. Esters of organic acids that may be used include those containing 20 to 30 carbon atoms, such as methyl acetate, ethyl propionate, methyl butyrate, propyl methacrylate, ethyl benzoate, phenyl benzoate, ethyl o-methoxybenzoate, methyl p-toluate, ethyl ··· naphthoate, ethyl or butyl phthalate or anisate.

# β · 25 Ethyl benzoate, 3,5-bis (1,1-dimethylethyl) -4-hydroxy ·, · cibenzenoctadecyl propanoate and dibutyl phthalate ···· • are particularly suitable. Examples of halides of organic acids include, for example, those containing 2 to 15 carbon atoms, such as acetyl chloride and tolyl chloride. Among the acid amides, there may be mentioned, for example, · · ·; 1 ’acetamide, benzamide and toluamide. Useful amines include, for example, diethylamine, piperidine, tri-t1-benzylamine, aniline and pyridine. As nitriles, for example, acetonitrile and benzonitrile may be used. As alkoxysilanes, tetraethoxysilane 21 117557 and dimethyl diethoxysilane may be used. Alcohols, ethers, esters and alkoxysilanes of organic acids are well suited. Esters of organic acids are preferred, in particular ethyl benzoate and dibutyl phthalate, and in particular ethyl benzoate.

The polymerization of the invention is carried out by contacting the olefin with a solid catalytic system containing a solid catalytic complex (a), an organometallic compound (b) that acts as an actin-10, and optionally an electron donor.

The olefin to be polymerized can be selected from olefins containing from 2 to 20 carbon atoms, preferably from 2 to 6 carbon atoms, such as ethylene, propylene, 1-butene, 4-methyl-1-pentene and 1-hexene. Ethylene, 1-butene and 15-hexene are well suited. Ethylene is particularly good. Of course, several different olefins may be used simultaneously, and in order to obtain copolymers, for example mixtures of the two olefins mentioned above, or one or more of these olefins with one or more diolefins, preferably containing 4-20 carbon atoms. These diolefins may be aliphatic non-conjugated diolefins, such as 1,4-hexadiene, monocyclic diolefins, such as *: 2'-4-vinylcyclohexene, 1,3-divinylcyclohexane, cyclopentyl, or lopentadiene, 5-Cyclooctadiene, alicyclic diols! j1; 25 phines containing an endocyclic bridge such as di-··· cyclopentadiene or norbornadiene and aliphatic concentrated diolefins such as butadiene and isoprene.

* a · ·. ; ·· ί

The process of the invention is particularly suitable for the preparation of homopolymers of ethylene and copolymers containing at least 90 mol% ethylene and preferably 95 mol% ethylene.

The polymerization according to the invention can be carried out.

! Dissolve in 1 l by any known method

; 1 "· timeen, which may be olefin even liquid or sus- ··· 4 • 1 · • · · 2 • · · · · · * ♦ ··· '.. · 22 117557" · *;> pensions hydrocarbon diluent or still in the gas phase.

Good results have been obtained by polymerization in suspension.

The polymerization in suspension is generally carried out in a hydrocarbon diluent such as liquid aliphatic, cycloaliphatic and aromatic hydrocarbons at a temperature of at least 80% (preferably at least 90%); the polymer formed is insoluble therein. Preferred diluents are straight chain alkanes such as n-butane, n-hexane and n-heptane, or branched al-10 cans such as isobutane, isopentane, isooctane and 2,2-dimethylpropane or cycloalkanes such as cyclopentane and cyclohexane or their alloys. Best results | it is obtained with hexane and isobutane. The polymerization temperature is generally selected from 20 to 200 ° C, preferably from 50 to 15 150 ° C, in particular 65 to 115 ° C. The partial pressure of the olefins is often chosen between normal pressure and 5 MPa, preferably between 0.2 and 2 MPa, in particular between 0.4 and 1.5 MPa.

In order to polymerize in the gas phase, a gas stream containing at least one olefin is contacted with the catalytic system, for example in a fluidized bed. Therefore, the velocity of the gas stream must be sufficient to keep the polyolefin fluid and depends on the rate of polymer formation-: · s c: * and the rate at which the catalytic system is burned. The total partial pressure of 01efin (s) may be lower • · • tJ | 25 or higher than normal pressure, best partial pressure varies *; · from normal pressure to about 7 MPa. Usually 0.2-5 MPa ···· • **; pressure is fine. Temperature selection is not critical, it is generally between 30 and 200 ° C. For dilution, it is possible to use a gas which must be a polyolefin. 30 inert.

f · * • · ·

The polymerization process of the invention may optionally be carried out by a molecular weight regulator such as hydrogen.

ί:: in the presence. % •; -, v: 1; The polymerization process of the invention can be carried out continuously or discontinuously, in one or more reactors connected in series, polymerization conditions (temperature, concentration of any comonomer, hydrogen concentration, type of polymerization medium) in one reaction vessel? 5 are different from the conditions used in the other reaction vessels.

The polymerization process of the invention can be used to produce polyolefins of high apparent density.

The following examples are intended to illustrate the invention. The meaning of the symbols used in these examples, the units expressing said quantities, and their orifices. thigh measurement methods are explained below.

MI2 = Polyolefin Flow Index, which refers to the velocity of 15 molten polyolefins at 190 ° C passing through a 2 mm diameter nozzle of> -¾ length to 8 mm by means of a piston (f) stabilized to a mass of 2.16 kg , this rate is expressed in g / 10 min according to ASTM D 1238 (1990).

20 PSA = apparent density of the polyolefin expressed in kg / m3 and measured as free-flowing under the following conditions: a 50 cm3 cylindrical * 'i ** · vessel is poured the polymer powder to be analyzed through a funnel having a bottom edge of 20 mm: 25 above the top. Weigh the powder M · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · ·

* *, ···, MVS = specific gravity of the polyolefin, expressed in kg / m3 · * · * / 5 and measured according to ISO 1183 (1987).

. 30 μ = dynamic viscosity of polyolefin • i »

in dPa.s and measured with a velocity gradient of 100 s -1 at 190 ° C. I

oc = activity of the solid catalytic complex *. "* · expressed in kg of insoluble polyolefin expressed as kg of titanium and MPa used per gram of insoluble polyolefin. per olefin pressure.

TO = the oligomer content of the polyolefin, expressed in grams of oligomer per kg of polyolefin and measured by extraction into boiling hexane.

In these examples, solid catalytic complexes are prepared which are then used to polymerize ethylene.

Example 1 (Comparison) In this example, ethylene is copolymerized with butene via a solid catalytic complex, prepared without further treatment with a halogenated organoaluminum compound.

A. Preparation of Solid Catalytic Complex 15 A.1. The first step of liquid complex formation

Magnesium diethylate prepared in situ by reacting metallic magnesium with ethanol was reacted for 5 hours at 110 ° C with titanium 20 nitetrabutylate in amounts such that the molar ratio of titanium to magnesium was equal to 2.

A.2. The second step of the precipitation of the liquid complex «" ** · A. The liquid complex obtained in (1) was precipitated by contacting it with a solution of isobutylaluminum dichloride in hexane (in an amount such that ·· * · ·· · The molar ratio of aluminum to titanium was equal to 6) Φ ···: stirring for 2 hours at 45 ° C.

• · ·

, ·· *. A.3. Maturation I

• · »

In section A.2. the resulting mixture was aged for 45 minutes, 30 hours at 60 ° C.

* * · ** · * A.4. The third step, followed by washing i • · * ··· * in A.3. recovered solid catalytic: *; * · The complex was washed with hexane. The resulting solid catalytic. * · * · Complex contained (% by weight): · · · · · · · · · · · · · · · · · · · · ···

Ti: 19.5 Cl: 63.2 Al: 2.8 Mg: 5.4.

The residue contained elements derived from compounds used to prepare the solid catalytic complex, such as carbon, hydrogen and oxygen.

B. Copolymerization of Ethylene

Ethylene was continuously copolymerized with butene in a sil-10 molten reactor to which hexane, ethylene (at a concentration of ethylene equal to 25 g / kg), hydrogen (at a molar hydrogen / ethylene ratio of 0.084), butene were continuously added (such that the molar ratio of butene / ethylene to 0.070 was 0.070), triethylaluminum (such that the concentration, expressed as aluminum in hexane, was equal to 27.5 ppm) and in Example 1A. the resulting solid catalytic complex. The temperature in the reactor was 78 ° C. The continuous process 20 was characterized by a production time of 2.15 hours and a yield of 19.6 kg / h. The recovered polyethylene had the following characteristics; -? 1 ....: features: MI2 * 1.9 • ·! **: 'MVS = 953.9 • · ·: 25 TO = 4.0 ···· * PSA = 330.

Example 2 (In accordance with the invention). In this example, a copolymer of ethylene and butene having MI2 and MVS of Example 1 was prepared (using the same concentration of hydrogen and butene as in the method of Example 1B) as a solid catalyst.

• «· through a complex made up of a single $ • · · **. ·? * with a single additional treatment such that the total amount of chlorine used (total sum of the second stage and further treatment: V: 35 ma) per alkoxy group (contained in the magnesium compound and • * · ♦ · · · * ··· 26 117557 transition metal compound) was the same as that used in Example 1.

A. Preparation of Solid Catalytic Complex A.1. First step of liquid complex formation

Magnesium diethylate prepared in situ by reacting metallic magnesium with ethanol was reacted for 5 hours at 110 ° C with titanium tetrabutylate in amounts such that the molar ratio of titanium to magnesium was equal to 1.

A.2. Second stage of precipitation of the liquid complex. The liquid complex obtained in A.1.1 was mixed by contacting it with a solution of isobutylaluminum dichloride 15 (IBADIC) in hexane (in an amount such that the molar ratio of aluminum to titanium was 4.5) with stirring for 75 minutes at 45 ° C.

A.3. maturation

In section A.2. the resulting mixture was aged for 60 minutes to 20 hours at 45 ° C.

A.4. The third step after washing

Captured in A.3. the resulting solid catalytic complex washed with hexane.

. * “A.5. External Treatment • · ·: * · / 25 The solid catalytic • · · ···· complex obtained in A, 4 was post-treated in hexane. Ice Cure *:: The treatment was added over 45 minutes at 45 ° C.

The amount of IBADIC is such that the ratio Al / Ti = 2.5.

A.6. Maturation and subsequent washing: 30 The solid catalytic complex obtained in 5A was matured for 45 minutes at 60 ° C. Catalytic • * * .1. the complex was finally washed with hexane. The resulting solid coverage * * · *; * / lytic complex contained (% w / w): 'TI: 11.9 35 Cl: 65.6 · · # • Φ Φ' 27: 27 117557 AI: 4, 3 Mg: 10.0 The residue contained elements derived from compounds used to prepare the solid catalytic complex, such as carbon, hydrogen and oxygen.

B. Copolymerization of Ethylene

Example l.B. the operations were repeated using the catalyst obtained in A under the following reaction conditions: 10 molar hydrogen / ethylene = 0.081 molar butene / ethylene = 0.054

The recovered polyethylene had the following characteristics: MI2 - 1.9 MVS = 953.6 TO = 5.0 PSA = 390. '

Comparison of Example 2 with Example 1 shows the advancement of the invention with respect to the apparent specific gravity of the polyol-20 fines obtained.

Example 3 (In accordance with the invention) In this example, ethylene was polymerized through a solid catalytic complex containing two different transition metals prepared by one additional treatment (*) (··· * 25).

* * · ···· A. Preparation of Solid Catalytic Complex • · • i ·:.: I A, l. The first * * · ... - v 'step ΐ of the liquid complex formation

Magnesium diethylate was reacted for 7 hours 30 at 140 ° C with titanium tetrabutylate and zirconium tetra -: ***: butylate in amounts such that the molar ratio of titanium to magnesium was 0.5 and zirconium? • * * *; [/ molar ratio to titanium was equal to 1.2.

• · * ··· * A.2. Second stage of precipitation of the liquid complex: Y: 35 The liquid complex obtained in A.1 was precipitated by contacting it with a solution of isobutylaluminum dichloride in an amount such that the molar ratio of aluminum to the titanium and total zirconium was equal to 8.2) with stirring for 90 minutes at 45 ° C / 5 A.3 Maturation The mixture obtained in A.2 was matured for 60 minutes at 45 ° C.

A.4. The third step and subsequent washing The solid catalytic complex prepared in A.3 and washed with hexane was recovered.

A.5. Further treatment of the solid catalytic complex obtained in A.4 to a suspension of lex in hexane was added with stirring isobutylaluminium chloride (such that the molar ratio of isobutyl-aluminum to total amount of titanium used and zirconium used was 1.8) for 30 minutes at 45 ° C.

A.6. Maturation and subsequent washing A. The mixture obtained in step 5 was matured for 90 minutes to 20 hours at 60 ° C. The resulting solid catalytic complex was then washed with hexane. The resulting solid catalytic complex contained (% by weight): i · · · t ·

Ti: 7.3 • «# ·: ···: Zr: 14.0 • ·: 25 Cl: 61.5

Al: 2.6: Mg: 6.6.

: * · *: The residue contained elements derived from the compounds used in the solid catalytic comp. . ·. 30 for lexis such as carbon, hydrogen and oxygen.

B. Polymerization of ethylene into a 3 liter autoclave equipped with a stirrer was charged with 1 l of hexane and 2 mmol of triisobutyl f aluminum. The temperature was then raised to 85 ° C, which was maintained constant during polymerization. Then * • i · j ··· '* was added. 29 117557 one dose of hydrogen at 0.6 MPa and ethylene. Then 8.0 mg of the solid catalytic complex obtained in A were injected. The partial pressure of ethylene was kept constant at 0.6 MPa for 2 hours. The autoclave 5 was then degassed and cooled. The α-activity of the catalytic * complex was 201. 140 g of polyethylene was recovered from the autoclave and had the following characteristics: MI2 = 0.58 MVS = 959.7 TO - 33 μ = 16,000.

Example 4 (In accordance with the invention) In this example, ethylene was polymerized through a solid catalytic complex prepared in the presence of electron donors and using one further treatment. '? A. Preparation of Solid Catalytic Complex The procedure of Example 3.A. was repeated. measures.

B. Treatment with Electron Donors To a suspension of the solid catalytic complex obtained in A.1 in hexane, ethyl libenzoate was added in an amount such that the molar ratio of ethyl benzoate to the total amount of titanium and zirconium used * * * 25 was used. was equal to 5. The thus obtained mixture was kept at * * 35 ° C and with stirring for 1 hour. The solid complex thus treated was then washed with hexane.

• · · V · C. Polymerization of ethylene

The procedure of Example 3.B. measures And inject! ♦ *; 12.7 mg of solid catalytic complex was fed. The α-activity of the catalytic · lithic complex was 172. The autoclave • * · recovered 191 g of polyethylene having the following characteristics: ** · MI2 6 6.5 35 MVS = 964.2 • *: ***. to = 15.0 • * * μ = 5,500.

Claims (18)

A process for the polymerization of olefins, which comprises reacting at least one olefin with a catalytic system containing: a) a solid catalytic complex containing magnesium, transition metal and halogen, and b) groups IA, HA, IIB, IIIA and IVA organometallic metal compound; Characterized in that said solid catalytic complex (a) is prepared in a first step by reacting at least one magnesium compound selected from organic oxygen-containing magnesium compounds and halogenated magnesium compounds with at least one transition metal group IVB or VB of the Periodic Table. with a compound selected from organic oxygen-containing transition metal compounds and halogenated transition metal compounds until a liquid complex is obtained, and in a second step treating said liquid complex with a halogenated organoaluminum compound of the general formula R 1 R 3 X 3; ·· hydrocarbon radical, X is halogen and n is less than 3,. ***. whereupon the liquid complex precipitates to a solid catalyst. and the solid catalytic complex "" precipitated from the reaction mixture in the third step is separated, and the solid catalytic complex separated in the third step is treated in the fourth step * * · '· *' halogenated organoaluminum compound of the general formula AlRnx3.n and recovering the solid catholyte lithic complex without prepolymerizing it. * · ·:. ,, ί A method according to claim 1, characterized in that the fourth step comprises a single treatment * * *, ···. with a halogenated organoaluminum compound. • · 3. A method according to claim 2, characterized in that the halogenated organoaluminum compound used in the fourth step is the same as the compound used in the second step 31 117557 and is used in an amount of 0.1 to 40 moles of aluminum per mole of the total amount of transition metal used. 3 ° 117557 Process according to one of Claims 1 to 3, characterized in that the second stage of the preparation of the solid catalytic complex is followed immediately by the maturation step. Process according to one of Claims 1 to 4, characterized in that the washing step is immediately followed by a third step in the preparation of the solid catalytic complex. Process according to one of Claims 1 to 5, characterized in that after the fourth step in the preparation of the solid catalytic complex, it is immediately followed by maturation and then washing. Method according to one of Claims 1 to 6, characterized in that the liquid complex from the first step is treated with an electron donor before the second step is carried out. A process according to any one of claims 1 to 6, characterized in that the solid catalytic complex from the fourth step is treated with a · 1 · electron donor before the solid catalytic solid. contacting the complex with an olefin. • · * *** ·, ·. 25 The process according to claim 7 or 8, characterized in that the electron donor is used in an amount of 0.01 - • ♦ ♦ 'It. * 50 moles per mole of the total amount of transition metal used. i The process according to any one of claims 1 to 6, characterized in that the polarization solution uses an electron donor mixed with the organometallic compound in a quantity such that the amount of electron donor used is such that aluminum the molar ratio of electron to 1 * · * donor is 0.01 to 100. 32 · 117557 The process according to any one of claims 7 to 10, characterized in that the electron donor is ethyl benzoate. The process according to any one of claims 1 to 11, characterized in that the magnesium compound is selected from organic oxygen-containing magnesium compounds. 13. A process according to claim 12, characterized in that the magnesium compound is selected from magnesium alkoxides. Process according to any one of claims 1 to 13: characterized in that the transition metal compound is selected from titanium tetraalkoxides. Process according to one of Claims 1 to 14, characterized in that the halogenated organoaluminium compound is selected from ethylaluminum dichloride or isobutylaluminum dichloride. Process according to Claim 15, characterized in that the halogenated organoaluminum compound 20 is isobutylaluminum dichloride. The method according to any one of claims 1 to 16, characterized in that the organometallic compound is selected from: 3; Made of triethylaluminum or triisobutylaluminum •. where from. • I «, ·, 25 Process according to one of Claims 1 to 17, characterized in that the olefin is ethylene. i · · ··· · I t 1 ···; ; : rt £ * · 1 • «1 * · · • · 1 * · * · ···! 't # 2 ··· 3 •; ··· • · · 1 «•. | i- «· t · · • · · • Φ · · 33 11 11 33 117557