ES2614244T3 - Catalyst components for the polymerization of olefins and catalysts obtained from them - Google Patents

Abstract

The catalyst components for the polymerization of olefins comprising Ti, Mg, Al, Cl and optionally ORI groups where RI is a C1-C20 hydrocarbon group, optionally containing heteroatoms, up to such an amount to produce a lower OR '/ Ti molar ratio at 0.5, characterized by the fact that at least 95% of Ti atoms are in a valence state of 4, that the porosity (PF), measured by the mercury method and by the pores with an equal or smaller radius at 1μm, it is at least 0.3 cm3 / g, and due to the fact that the molar ratio Cl / Ti molar is less than 29.

Description

DESCRIPTION

Catalyst components for the polymerization of olefins and catalysts obtained from them

The present invention relates to catalyst components for the polymerization of olefins CH2 = CHR, where R is a hydrogen or hydrocarbon radical having between 1 and 12 carbon atoms. In particular, the invention relates to catalyst components suitable for the preparation of homopolymers and copolymers of ethylene and catalysts obtained therefrom. In addition, the invention also relates to ethylene homo or copolymers having high melt flow and good morphological properties and high molecular weight ethylene polymers with spherical shape and good morphology.

In particular, the present invention relates to a solid catalyst component, which comprises titanium and magnesium and halogen, which have a specific combination of chemical and physical characteristics. 10

In addition, the present invention relates to a process for preparing ethylene homopolymers and copolymers characterized by a high melt flow ratio (F / P) value, which is the ratio between the melt index measured with a load of 21 , 6 kg (melt index F) and the melt index measured with a load of 5kg (melt index P), determined at 190 ° C in accordance with ASTM D-1238. Such an F / P ratio is generally considered as an indication of the extent of molecular weight distribution (MWD). fifteen

MWD is a particularly important characteristic for ethylene (co) polymers, in that it affects rheological behavior and therefore the processability of fusion, and the final mechanical properties. Polyolefins having broad MWD, particularly coupled with relatively high average molecular weights, are preferred in blow molding and high speed extrusion processing, for example, for tube production. In fact, products characterized by a broad MWD have superior mechanical properties that allow their use in applications where high tensile strength is required. The processing conditions for these polymers are peculiar and in fact, under such conditions, a reduced MWD product may not be processed because it would fail due to the fusion fracture.

As it is difficult to have available catalysts that offer the correct pattern of molecular weight distribution and average molecular weight, one of the most common methods for preparing polymers with high MWD is the multi-stage process based on the production of polymer fractions. of different molecular weight at each stage, consecutively forming macromolecules of different length.

The molecular weight control obtained at each stage can be carried out in accordance with different methods, for example, by varying the polymerization conditions or the catalyst system at each stage, or by using a molecular weight regulator. Hydrogen regulation is the preferred method of working in suspension or gas phase. 30 The latter is a type of process that is currently preferred due to the high quality of the products obtained and the low operating costs involved.

For a catalyst to function in said process, a critical stage is that in which a fraction of low molecular weight is prepared. In fact, one of the important characteristics that the catalyst should possess is the so-called "hydrogen response", which is the ability to reduce the molecular weight of the polymer produced with respect to higher concentrations of hydrogen. A higher hydrogen response means that a smaller amount of hydrogen is required to produce a polymer with a certain molecular weight. In turn, this would normally involve a higher polymerization activity since the amount of hydrogen, which may have a depressive effect on the activity of the catalyst, may be relatively lower.

In addition, due to the polymerization conditions and the characteristics of the polymer produced at this stage (an intrinsically greater fragility), the catalyst / polymer system is usually fragmented into very small particles that decrease the bulk density of the polymer and create a high amount of particles that hinder the operation of the plant, particularly in the gas phase polymerization. One of the ways to avoid this problem would be to perform the preparation stage of the low molecular weight fraction after a first stage in which the high molecular weight fraction is prepared. Although this option could help to facilitate the operation of the plant, it surely causes a worsening of the final ownership of the product that turns out to be less homogeneous. Therefore, it would be an important feature of the catalyst that has adequate morphological resistance under low molecular weight gas phase polymerization conditions.

Catalysts are disclosed in EPA-A-601525 that in some cases can produce ethylene polymers with ample MWD (F / E ratios of 120 are reported, where F / E means the ratio between the melt index measured with a 50% load of 21.6 kg (melt index F) and the melt index measured with a load of 2.16 kg (melt index E), determined at 190 ° C in accordance with ASTM D-1238). Said catalysts are obtained by a reaction between a Ti compound and a MgCl2 · EtOH adduct which has been subjected firstly to a physical de-alcoholization and subsequently to a chemical de-alcoholization carried out with an alkyl aluminum compound. As a result, unless a preventive deactivation treatment of Al-alkyl residues is carried out, a substantial amount of the fixed Ti compound in the final catalyst component has an oxidation state of less than 4. When a treatment is carried out of preventive deactivation, the Ti fixed in the catalyst is much smaller with a consequence that said catalyst has a high Cl / Ti molar ratio and more than the titanium residue. Patent application

reported good yields in terms of morphological resistance (expressed by bulk density) under conventional suspension polymerization conditions, which, however, are not predictive of behavior under low molecular weight polymerization conditions when a high amount of molecular weight regulator (hydrogen). The applicant has carried out polymerization tests under those demanding conditions and has verified that a substantial amount of catalyst was separated in the early stages of polymerization resulting in polymer particles and / or irregular morphology reaching a final bulk density low.

In WO00 / 78820, catalysts capable of producing ethylene polymers with a broad MWD characterized by a total porosity (mercury method), preferably in the range 0.38-0.9 cm3 / g, and a surface area (BET method) are disclosed. preferably in the range 30-70 m2 / g. Poral distribution is also specific; in particular, in all the catalysts described in the examples, at least 45% of the porosity is due to pores with radii of up to 0.1 µm. The catalyst components are obtained by (a) a first reaction between a Ti compound and a MgCl2 · EtOH adduct that has been subjected to physical de-alcoholization, (b) an intermediate treatment with an alkyl aluminum compound and (c) by a second reaction with titanium compound. In addition, in this case, the catalysts contain a substantial amount of titanium, which has a reduced oxidation state and in addition, they show a low amount of residual A1 in the final catalyst. Without prejudice to the good yields under conventional polymerization conditions, it shows an unsatisfactory behavior under conditions of proof of demand used by the applicant. This is also confirmed in said document by the fact that when the polyethylene with ample MWD is prepared with two consecutive polymerization steps, the low molecular weight fraction is always prepared in the second polymerization stage. twenty

Therefore, a catalyst is still needed that has a high morphological stability under polymerization conditions of low molecular weight ethylene while maintaining high activity characteristics.

The applicant has surprisingly discovered that catalysts presenting the following combination of characteristics are able to meet the needs. Therefore, an object of the present invention is a catalyst component comprising Ti, Mg, Al, Cl and optionally ORI groups wherein RI is a C1-C20 hydrocarbon group, optionally containing heteroatoms, up to such an amount to produce an OR '/ Ti molar ratio of less than 0.5, characterized by the fact that substantially all titanium atoms are in a valence state of 4, than the porosity (PF), measured by the mercury method and by the pores with a radius equal to or less than 1µm, is at least 0.30 cm3 / g, and due to the fact that the molar ratio Cl / Ti molar is less than 29.

Preferably, in the catalyst of the present invention, the Cl / Ti molar ratio is less than 28, more preferably less than 25 and more preferably between 12 and 23. The Mg / Al molar ratio may range from 1 to 35, preferably between 3 and 30, more preferably between 4 and 20 and more preferably between 4 and 16. In the present application the phrase "substantially all titanium atoms are in a valence state of 4" means that at least 95% of the atoms of Ti have a valence state of 4. Preferably, the content of Ti atoms with a valence state of less than 4 is less than 0.1% and more preferably they are absent (not detectable with the applied method described in the characterization section). The amount of Ti is typically greater than 1.5%, preferably greater than 3% and more preferably equal to, or greater than 3.2% by weight. More preferably it ranges between 3.5% and 8% by weight. The amount of Al is typically greater than 0.5% by weight, preferably greater than 1% and more preferably in a range between 1.2 and 3.5%. Preferably, the amount of Al is less than that of Ti. The catalyst of the present invention shows another peculiar characteristic. The amount of total anions 40 detected, in accordance with the methods described in the characterization section, in the solid catalyst component, are usually not sufficient to satisfy the total of positive valences that derive from the cations that include, but not Taxative, Mg, Ti and Al even taking into account the possible presence of OR groups. In other words, it has been noted that in the catalyst of the invention, there is usually an absence of an amount of anions to meet all the valence of cations. In accordance with the present invention, this missing amount is defined as "LA factor" where "LA factor" is the molar equivalent of missing anionic species to satisfy all molar equivalents of the cations present in the solid catalyst component that have not Having been satisfied by the total molar equivalent of anions present in the solid catalyst component, all molar equivalents of anions and cations are called the molar amount of Ti.

The "LA factor" is determined by first calculating the molar contents of the anions and cations detected 50 by the analysis. The molar content in relation to all anions (including, for example, Cl- and -OR) and cations (including, for example, Mg, Ti and Al) refers to Ti by dividing it by the molar amount of Ti that is considered as the molar unit Subsequently, the total number of molar equivalents of cations to be satisfied is calculated for example by multiplying the molar amount of Mg ++ (called Ti) by two, the molar amount of Ti + 4 (molar unit) by four, and the molar amount of At + 3 times three, respectively. The total value obtained is subsequently compared with the sum of the molar equivalents derived from anions, for example, the CI and OR groups, always called titanium. The different resulting from the comparison and in particular the negative balance obtained in terms of molar equivalents of anions, indicates the "LA factor".

The "LA factor" is usually greater than 0.5, preferably greater than 1 and more preferably in a range of 1.5 to 6. Although the examples that arise from this trend are possible, it has been observed that in general how much greater 60 is the molar content of Al, greater is the "LA factor". It has also been discovered that the relationship "LA / Al + Ti", where Al

is the molar amount of Al called Ti and Ti is the molar unit, is greater than 0.5, preferably greater than 0.7 and more preferably greater than 0.9 to 2. Without being interpreted as a limited interpretation of the invention is it is possible that the LA factor is related to the formation of compounds in which two or more metal atoms are coupled by [-O-].

In addition to the above characteristics, the catalysts of the invention preferably show a porosity 5 PF determined by the mercury method greater than 0.40 cm3 / g and more preferably greater than 0.50 cm3 / g generally in the range 0.50-0, 80 cm3 / g. The total porosity PT may be in the range of 0.50-1.50 cm3 / g, particularly in the range between 0.60 and 1.20 cm3 / g, and the difference (PT-PF) may be greater than 0 , Preferably in the range between 0.15 and 0.50.

The surface area measured by the BET method is preferably less than 80 and in particular between 10 10 and 70 m2 / g. The porosity measured by the BET method is generally between 0.10 and 0.50, preferably between 0.10 and 0.40 cm3 / g.

In a preferred aspect, the catalyst component of the invention comprises a Ti compound having at least one Ti-halogen bond, a magnesium chloride and an aluminum chloride or more generally, an aluminum halide. As mentioned above, the catalyst component may also contain different groups of halogen, in any case in amounts less than 0.5 mol for each mole of titanium and preferably less than 0.3. In the present application, the term magnesium chloride means a magnesium compound having at least one Mg-Cl bond, the term aluminum chloride means an aluminum compound containing at least one Al-Cl bond and the term aluminum halide means an aluminum compound that contains at least one Al-X bond, where X is Cl, Br or I. 20

In the catalyst component of the invention, the average polar radius value, for porosity due to pores up to 1 µm, is in the range between 65 and 120 nm (650 and 1200 Å).

The solid component particles have a substantially spherical morphology and an average diameter between 5 and 150 µm, preferably between 20 and 100 µm and more preferably between 30 and 90 µm. As particles having substantially spherical morphology, these are where the interval between the major axis and the minor axis 25 is equal to or less than 1.5 and preferably less than 1.3.

The magnesium chloride is preferably magnesium dichloride and more preferably in the active form which means that it is characterized by an X-ray spectrum in which the largest intense diffraction line that appears in the non-active chloride spectrum (lattice distance of 0.256 nm (2.56 Å)) decreases in intensity and expands to the point that it merges totally or partially with the reflection line that falls in the lattice distance (d) of 0.295 30 nm (2.95Å). When the fusion is complete, the only peak generated has the maximum intensity, which changes to angles lower than those of the most intense line.

The components of the invention may also comprise an electron donor compound (internal donor), selected for example from ethers, esters, amines and ketones. Said compound is necessary when the component is used in the (co) polymerization of olefins such as propylene, 1-butene, 4-methyl-pentene-1. In particular, the internal electron donor compound may be selected from alkyl, cycloalkyl and aryl ether and esters of polycarboxylic acids, such as, for example, esters of phthalic and maleic acid, in particular, n-butylphthalate, diisobutylphthalate, di-n- octylphthalate

Other electron donor compounds advantageously used are 1,3-dieters particularly disclosed in EP 361494, EP361493, and EP728769. 40

If present, the electron donor compound is in a molar ratio to magnesium between 1: 4 and 1:20.

Preferred titanium compounds have the formula Ti (ORI) nXy-n, where n is a number between 0 and 0.5 inclusive, and is the valence of titanium, RI has the meaning assigned above and is preferably alkyl radical , cycloalkyl or aryl having 1 to 8 carbon atoms and X is halogen. In particular RI may be methyl, ethyl, isopropyl, n-butyl, isobutyl, 2-ethylhexyl, n-octyl and phenyl: X is preferably chlorine.

The aluminum halide can be chosen from those of the formula AlXL2 where X is halogen as defined above and L can be, independently, ORI groups as defined above or halogen.

Preferably, the aluminum halide is aluminum chloride of the formula AlClL2 where L can be, independently, ORI groups as defined above or chlorine. Preferably, L is chlorine. However, as mentioned above, it is also possible the presence of cyclic species that contain the repeating unit of formula - [MLv-2O-] p-in which M is independently Al or Ti, v is the valence of M , p is at least 2 and L has the previously assigned meaning and preferably chlorine and the presence of linear species of formula MLv-1-O- [ML v-2O-] n-MLv-1 where M, L and v have the The meaning assigned above and n ranges from 0 to 10. Preferably, in the last formula M is Al and L is Cl. Species of formula 55 ROAlCl- [AlClO-] AlCl2 are also preferred.

The catalyst of the invention can be prepared according to several methods. One of the preferred methods comprises a step (a) in which a MgCl2.mRIIOH tH2O compound, where 0.3 ≤ m ≤ 1.7, t ranges between 0.01 and 0.6, and RII is an alkyl radical, cycloalkyl or aryl having between 1 and 12 carbon atoms, reacts with a titanium compound of formula Ti (ORI) nXy-n, in which n ranges between 0 and 0.5, and is the valence of titanium, X is halogen and RI has the meaning assigned above and preferably it is an alkyl radical having between 1 and 8 carbon atoms, 5 in the presence of an aluminum compound of formula AlL3 where L may independently be ORI groups as defined above or halogen . Preferably, at least one L is chlorine, more preferably two L are chlorine and more preferably all L are chlorine.

In this case MgCl2.mRIIOHtH2O represents a precursor of Mg dihalide. These types of compounds can generally be obtained by mixing alcohol and magnesium chloride in the presence of an immiscible inert hydrocarbon 10 with the adduct, which operates under conditions of stirring at the melting temperature of the adduct (100-130 ° C). The emulsion heats up quickly, causing the adduct to solidify in the form of spherical particles. Representative methods for the presentation of these spherical adducts are reported, for example, in USP 4,469,648, USP 4,399,054 and WO98 / 44009. Another example usable for splinting is spray cooling described, for example, in USP 5,100,849 and 4,829,034. The adducts having the desired final alcohol content can be obtained directly using the selected amount of alcohol directly during the preparation of the adduct. However, if adducts with higher porosity are to be obtained, it is convenient to prepare, in the first place, adducts with more than 1.7 moles of alcohol per mole of MgCl2 and subject them to a thermal and / or chemical de-alcoholization process. The thermal de-alcoholization process is carried out in nitrogen flow at temperatures between 50 and 150 ° C until the alcohol content is reduced to the value that ranges between 0.3 and 1.7. Such a process is described in EP 395083.

Generally, these desalcoholizados adducts are also characterized by a porosity (measured by the mercury method) due to pores with radii of up to 0.1 µm ranging between 0.15 and 2.5 cm3 / g preferably, between 0.25 and 1, 5 cm3 / g.

In the reaction of step (a), the Ti / Mg molar ratio is stoichiometric or greater, preferably this ratio is greater than 3. Even more preferably, a greater excess of titanium compound is used. Preferred titanium compounds are titanium tetrahalides, in particular TiCl4. The reaction with the Ti compound can be produced by suspending the adduct in cold TiCl4 (generally 0 ° C); The mixture is heated to 80-140 ° C and maintained at this temperature for 0.5-5 hours. Preferably, the reaction times at the greater end of the range are suitable in correspondence of the reaction temperature at the lower end of the range. The excess of titanium compound can be separated at high temperatures by filtration or sedimentation and deflection. As mentioned above, the reaction occurs in the presence of the aforementioned aluminum compound, preferably AlCl 3, which is used in amounts to have a Mg / Al molar ratio that can range between 1 and 35, preferably between 3 and 30, more preferably 4 and 20 and more preferably in the range of 4 to 16. The catalyst component recovered and washed in accordance with conventional techniques is already available to show the good yields previously disclosed. However, it has been found that improved yields can be obtained when in a second stage (b) of the method, the solid product that comes from stage (a) is subject to a heat treatment produced at temperatures greater than 50 ° C, preferably greater than 70 ° C, more preferably greater than 100 ° C, especially greater than 120 ° C and more preferably greater than 130 ° C. Temperatures at the lower end of the range are particularly preferred when AlCl2OR compounds are used in which R is a branched alkyl group.

The heat treatment is done in different ways. According to one of them, the solid produced from step (a) is suspended in an inert diluent such as a hydrocarbon and subsequently subjected to heating while maintaining the system under stirring.

According to an alternative technique, the solid can be heated in a dry state by inserting it into a device that has heated heated walls. Although stirring can occur with mechanical stirrers placed in said device, it is preferred that stirring occurs using rotating devices.

According to a different embodiment, the solid from (a) can be heated by subjecting it to a flow of hot inert gas such as nitrogen, preferably keeping the solid in fluidization conditions.

In accordance with a further embodiment, heating occurs by another reaction with an excess titanium compound 50 carried out at said high temperatures.

The heating time is not fixed but may vary depending on other conditions such as the maximum temperature reached. It usually ranges between 0.1 and 10 hours, more specifically between 0.5 and 6 hours. In general, higher temperatures make it possible to shorten the heating time while, on the opposite side, lower temperatures may require longer reaction times. 55

According to another embodiment the catalyst of the invention can be prepared by a process comprising a step (a) in which a MgCl2.mRIIOH tH2O compound, where 0.3 ≤ m ≤ 1.7, t ranges from 0.01 and 0.6, and RII is an alkyl, cycloalkyl or aryl radical having between 1 and 12 carbon atoms, reacts with a compound

of titanium of formula Ti (ORI) nXy-n, in which n ranges from 0 to 0.5, and is the valence of titanium, X is halogen and RI has the previously assigned meaning and a second stage (b), in where the solid product that comes from (a) reacts again with the titanium compound in the presence of an aluminum compound of formula AlL3 where L can be, independently, ORI groups as defined above or halogen or chlorine, preferably AlClL2. 5

If desired after this step (b), the solid product may be subjected to heat treatment in accordance with one of the processes and conditions described above.

Finally, according to a different method, the catalyst components are obtained by a method comprising a step (a) in which a compound MgCl2.mRIIOH tH2O, where 0.3 ≤ m ≤ 1.7, t ranges from 0, 01 and 0.6, and RII is an alkyl, cycloalkyl or aryl radical having between 1 and 12 carbon atoms, reacts with a titanium compound of formula Ti (ORI) nXy-n, in which n ranges from 0 and 0.5, and is the valence of titanium, X is halogen and RI has the previously assigned meaning and a second stage (b), wherein the solid product that comes from (a) is subjected to a heat treatment in the presence of an aluminum compound of formula AlL3 where L may independently be ORI groups as defined above or halogen. Preferably, at least one L is chlorine in accordance with the formula preferably AlClL2. Said heat treatment is carried out in accordance with any of the processes and conditions described above.

Regardless of the method used to prepare the solid catalyst component of the invention, it has been advantageous to carry out a final treatment of the catalyst comprising contacting said solid catalyst component with an electron donor compound preferably chosen among ether, ketone, ester and silicon. Preferably, said electron donor compound is chosen from diesters and diketones, and more preferably, from 1.3 diesters.

Preferred diesters are 9.9 dimethoxy fluorene and 1,3-dieters mentioned in EP 728769 among which 9,9-bis (methoxymethyl) fluorene is preferred. Among the diketones, aliphatic diketones are preferred and among them acetylacetone is the most preferred. The contact is preferably produced in an inert hydrocarbon as a diluent at a temperature ranging from room temperature to the donor boiling temperature, generally between 40 and 150 ° C and preferably between 50 ° C and 140 ° C. The electron donor compound can be used in the molar ratio with the Ti compound in the solid catalyst component that comes from step (b) and ranges between 5 and 0.01, preferably between 1 and 0.1 and more preferably between 0.8 and 0.1. The donor becomes fixed in the catalyst component in several amounts that do not appear to correlate with the effect on morphological stability, that is, with the ability of the catalyst to produce high bulk density polymers even under 30 demanding test conditions used by the applicant. In fact, the positive effect on morphological stability is always present even when the amount of the fixed donor is very low or possibly absent. In particular, treatment with the donor allows the catalyst to have an even greater morphological stability evidenced by the fact that the polymer with high bulk density is also obtained by polymerizing ethylene in the presence of a high amount of hydrogen and by using of triethylaluminum as cocatalyst, which are known as extremely demanding conditions.

The catalyst components of the invention, regardless of the method of preparation, form catalysts for the polymerization of alpha-olefins CH2 = CHRIII where RIII is hydrogen or a hydrocarbon radical having between 1 and 12 carbon atoms per reaction with Al-alkyl compounds. In particular, Al-trialkyl compounds, for example, Al-trimethyl, Al-triethyl, Al-tri-n-butyl, Al-triisobutyl are preferred. The Al / Ti ratio is greater than 40 1 and generally ranges from 5 to 800.

In the case of stereoregular polymerization of α-olefins such as propylene and 1-butene, an electron donor compound (external donor) that can be the same or different from the compound used as an internal donor is also generally used in the preparation of the catalyst . When the internal donor is a polycarboxylic acid ester, in particular a phthalate, the external donor is preferably selected from silane compounds containing at least one Si-OR bond, having the formula RIX 4-nSi (ORX) n , where RIX is an alkyl, cycloalkyl, aryl radical having between 1 and 18 carbon atoms, RX is an alkyl radical having between 1 and 4 carbon atoms and n is a number between 1 and 3. Examples of these silanes they are methyl-cyclohexyl dimethoxysilane, diphenyldimethoxysilane, methyl-t-butyl dimethoxysilane, dicyclopentyldimethoxysilane.

It is possible to advantageously use 1,3-dieters having the formula described above. In the case where the internal donor is one of these diesters, the use of an external donor can be avoided, since the stereospecificity of the catalyst is already high enough.

The spherical components of the invention and the catalysts obtained therefrom find applications in processes for the preparation of various types of olefin polymers.

As mentioned above, the catalyst of the invention has a particularly high morphological stability at a high concentration of hydrogen for the preparation of a low molecular weight ethylene (co) polymer. Therefore, they are particularly used in cascade processes, or sequential polymerization, for the preparation of ethylene polymers of large molecular weight in suspension and in the gas phase. In general, the catalyst can be

use to prepare: high density ethylene polymers (HDPE, having a density greater than 0.940 g / cm3), which comprise ethylene homopolymers and ethylene copolymers with alpha-olefins having between 3 and 12 carbon atoms; linear low density polyethylenes (LLPDE, which have a density less than 0.940 g / cm3) and a very low density and an ultra low density (VLDPE and ULDPE, which have a density less than 0.920 g / cm3, at 0.880 g / cm3 ) consisting of copolymers of ethylene with one or more alpha-olefins having between 3 and 12 carbon atoms, having a mole content of ethylene-derived units greater than 80%; elastomeric copolymers of ethylene and propylene and elastomeric terpolymers of ethylene and propylene with smaller proportions of a diene having a weight content of units derived from ethylene between about 30 and 70%, isotactic polypropylenes and crystalline copolymers of propylene and ethylene and / or other alpha-olefins having a content of units derived from propylene greater than 85% by weight; shock-resistant propylene polymers 10 obtained by consecutive polymerization of propylene and mixtures of propylene with ethylene, containing up to 30% by weight of ethylene; propylene and 1-butene copolymers having a number of units derived from 1-butene comprised between 10% and 40% by weight.

However, as indicated above, they are particularly suitable for the preparation of polymers with ample MWD and in particular ethylene homopolymers with ample MWD and copolymers containing up to 20% mol per mole of higher α-olefins such as propylene, 1- butene, 1-hexene, 1-octene.

An additional advantage of the catalyst described in the present application is that it can be used as such in the polymerization process by its introduction directly into the reactor without the need to pre-polymerize it. This allows plant assembly planning and catalyst preparation process to be simpler.

The main polymerization process in the presence of catalysts obtained from the catalyst components of the invention can be carried out in accordance with known techniques in the liquid or gas phase using for example the known fluidized bed technique or under conditions in which the polymer is mechanically stirred. However, the preferred process occurs in the gas phase fluidized bed reactor. Whatever the process, the catalyst described above, by virtue of the good stability of its morphological particles, can withstand polymerization temperatures higher than standard, which are higher than 25 80 ° C and in particular are in the range of 85 ° C - 100 ° C. As the higher polymerization temperatures allow simultaneous higher yields and more efficient heat removal due to the greater difference between the polymerization temperature and the cooling fluid, it is found that with the catalyst of the invention, the productivity of The polymerization plant is greatly improved.

Examples of gas phase processes where it is possible to use the spherical components of the invention are described in WO92 / 21706, USP 5,733,987 and WO93 / 03078. In the processes, a prior contact stage of the catalyst components, a pre-polymerization stage and a gas phase polymerization stage in one or more reactors in a series of fluidized bed or mechanically agitated bed are included even if, as mentioned previously, they are not necessarily required with the catalyst of the invention.

Therefore, in case the polymerization takes place in the gas phase, the process of the invention is preferably carried out in accordance with the following steps:

(a) contacting catalyst components in the absence of a polymerizable olefin or optionally in the presence of said olefin in amounts not exceeding 20 g per gram of solid component (A);

(b) gas phase polymerization of ethylene or mixtures thereof with α-olefins CH2 = CHR, wherein R is a hydrocarbon radical having between 1 and 10 carbon atoms, in one or more fluidized or mechanically stirred bed reactors 40 using the catalyst system of (a).

As mentioned above, to extend the MWD of the product, the process of the invention can be carried out in two or more reactors operating under different conditions and optionally by recycling, at least partially, of the polymer that is formed in the second reactor. of the first reactor. In general, the two or more reactors operate with different concentrations of molecular weight regulator or at different temperatures of polymerization or both. Preferably, the polymerization occurs in two or more stages that operate with different concentrations of the molecular weight regulator.

As explained above, one of the most interesting characteristics of the catalysts described above is the ability to produce ethylene polymers with low molecular weight, expressed by the "E" value of the high melt index and good morphological properties expressed by high values of bulk density. In particular, said ethylene polymers have a melt index E greater than 50 and bulk densities greater than 0.35. Particularly preferred are those having an "E" MI greater than 70 and a bulk density greater than 0.37 and those with "E" MI in the range of 80-400 and a bulk density between 0, are even more preferred. 4 and 0.6. When these types of polymers are produced in the low molecular weight polymerization stage of a multi-stage process, they allow obtaining ethylene polymers having the same broad MWD generally expressed by a melt flow ratio (F / P ) greater than 20, preferably greater than 25, and more preferably greater than 35, which is the ratio between the melt index measured with a load of 21.6 kg (melt index F), and the melt index measured with a load of 5 kg (melt index P), determined at 190 ° C in accordance with ASTM D-1238,

a bulk density greater than 0.44, preferably greater than 0.46 and a preferably good homogeneity expressed by a number of gels (determined by the method described below) which have a diameter of more than 0.2 mm less 70 and preferably less than 60. In addition, the films preferably do not contain gels with a diameter greater than 0.5 mm. Once used in the production of films or tubes, the polymers showed a very good processability while the extrudates 5 showed a very low number of gels. The polymer is obtained in the form of spherical particles which means that the ratio between the major axis and the minor axis is equal to or less than 1.5 and preferably less than 1.3.

The following examples are provided to describe the present invention.

The properties are determined in accordance with the following methods:

Porosity and surface area with nitrogen: determined in accordance with the B.E.T. (device used 10 by SORPTOMATIC 1900 by Carlo Erba).

Porosity and surface area with mercury:

The measurement is performed using a series "Porosimeter 2000" by Carlo Erba.

Porosity is determined by absorption of mercury under pressure. For this determination, a calibrated dilatometer (diameter 3 mm) CD3 (Carlo Erba) connected to a mercury tank and a vacuum pump 15 (1 · 10-2 mbar) is used. A weighted amount of sample is placed in the dilatometer. The device is subsequently placed under vacuum (<0.1 mm Hg) and maintained under these conditions for 20 minutes. The dilatometer is then connected to the mercury reservoir and the mercury flows into it until it reaches the level marked on the dilatometer at a height of 10 cm. The valve that connects the dilatometer to the vacuum pump closes and then the mercury pressure gradually increases with nitrogen to 140 kg / cm2. Under the effect of pressure, mercury enters 20 in the pores and the level falls in accordance with the porosity of the material.

The porosity (cm3 / g), total and that generated by the pores up to 1µm, the polar distribution curve and the average pore size are calculated directly from the integral polar distribution curve which is the function of volume reduction of the mercury and the applied pressure values (all these data are provided and elaborated with the porosimeter, which is equipped with a MILESTONE 200 / 2.04 "program by C. Erba. 25

MIE flow rate: Condition E ASTM D-1238

MIF flow rate: Condition F ASTM D-1238

MIP flow rate: Condition P ASTM D 1238

Bulk Density: DIN-53194

Ti Determination (red) 30

0.5 g of the sample is dissolved as a powder in 100 ml of 2.7M HCl in the presence of solid CO2. The solution obtained is subsequently subjected to a volumetric titration with a solution of FeNH4 (SO4) 2 · 12H2O 0.1N, in the presence of solid CO2, using NH4SCN as an indicator of equivalence point (25% water solution). Stoichiometric calculations based on the volume of titration agent consumed give the amount by weight of Ti3 + in the sample. 35

Determination of Mg, Ti (tot) and Al: was carried out by means of an inductively coupled plasma emission spectrometry (ICP) in a spectrometer "I.C.P SPECTROMETER ARL Accuris".

The sample was prepared by analytically weighing, in a "flowing" platinum crucible, 0.1 ÷ 03 g of catalyst and 3 g of 1/1 lithium metaborate / tetraborate mixture. The crucible was placed in a weak Bunsen flame for the burning stage and subsequently after the addition of a few drops of KI solution it was inserted in a special apparatus "Claisse Fluxy" for complete burning. The residue was collected with 5% v / v HNO3 solution and analyzed by ICP at the following wavelength: Magnesium, 279.08 nm; Titanium, 368.52 nm; Aluminum, 394.40 nm.

IC determination: was performed by potentiometric titration.

Determination of OR groups: by gas chromatography analysis.

Determination of the gel number: 45 kg of polymer are added with Irgafox 168 (0.15% by weight), ZnO (0.15% by 45 weight), zinc stearate (0.05% by weight), PPA-VITOW Z100 (0.03% by weight) and are granulated with a WP (Werner & Pfliderer) ZSK 40 double screw extruder plus gear pump plus a water granulator, keeping the temperature at 230 ° C in all sections at a production of 38 Kg / h. The product is subsequently extruded into a blown film using a Dolci KRC 40 groove extruder, with a barrel temperature profile of 220-225-225-220 ° C and 230-230 ° C in dead zones. The production is 28kg / h at 50 rpm. The film is extruded 50 with a blowing ratio (BUR) of 4: 1, a neck length of 7.5: 1 at a thickness of 20 microns. The determination of the number of gels per m2 is done by visually detecting the number of gels that have the

Longer shaft size greater than 0.2 mm in a piece of extruded film (25x7.5 cm in size) that is projected by a projector, on a wall chart with a magnified scale. The count is made on 5 different pieces of the same film and a final number is obtained by means of the expression No = A / S where It is not the number of gels per m2, A is the number of gels counted in 5 pieces of film and S It is the total area in m2 of the 5 pieces of film examined. 5

Polymerization of ethylene: general procedure A.

A 4.5 liter stainless steel autoclave equipped with a magnetic stirrer, temperature and pressure gauge, feed line for hexane, ethylene and hydrogen was used, and purified by melting pure nitrogen at 70 ° C for 60 minutes. Subsequently, a 1550 cm3 solution of hexane containing 7.7 cm3 of 10% in w / vol was introduced. TiBAL / hexane at a temperature of 30 ° C under nitrogen flow. In a glass bottle 10 of round base of 200 cm3, 50 cm3 of anhydrous hexane, 1 cm3 of 10% in p / vol were successively introduced. of TiBAL / hexane solution and 0.040 ÷ 0.070 g of solid catalyst from table 1. They were mixed, stationed for 10 minutes at room temperature and introduced under nitrogen flow into the reactor. The autoclave was closed, subsequently the temperature was raised to 85 ° C, and hydrogen (9 bar at partial pressure) and ethylene (3.0 bar under partial pressure) were added. fifteen

Under continuous stirring, the total pressure was maintained at 85 ° C for 120 minutes by feeding with ethylene. Finally, the reactor was depressurized and the temperature dropped to 30 ° C. The recovered polymer was dried at 70 ° C under nitrogen flow and analyzed. The results obtained are reported in table 2.

General ethylene polymerization process (procedure B)

The procedure was carried out under the same conditions disclosed for procedure (A) with the only difference that triethylammonium was used instead of triisobutylammonium.

EXAMPLES

PREPARATION OF THE SPHERICAL SUPPORT (ADUCT MgCl 2 / EtOH)

An adduct of magnesium chloride and alcohol was prepared following the method described in Example 2 of USP 4,399,054 but working at 2000 RPM instead of 1000 RPM. The adduct containing about 3 moles of 25 alcohol and 3.1% by weight of H2O and had an average size of about 70 µm. The adduct was subjected to a heat treatment, in a stream of nitrogen, at a temperature range of between 50 and 150 ° C until a weight content of 25% alcohol was reached.

EXAMPLE 1

Preparation of the solid component 30

In a round four-necked 450 mL flask, purged with nitrogen, 300 mL of TiCl4 and 1.34 g of anhydrous AlCl3 were introduced at 25 ° C and cooled to 0 ° C. Subsequently, at the same temperature, 20.9 g of a spherical MgCl2 / EtOH adduct containing 25% by weight of ethanol were added and prepared as described above under stirring. The temperature rose to 135 ° C in 100 minutes and was maintained for 120 minutes. Subsequently, the temperature decreased to 130 ° C, stirring was stopped, the solid product was allowed to stand for 30 minutes and the supernatant was obtained. The solid residue was subsequently washed five times with hexane at 60 ° C, once at room temperature and dried under vacuum at 30 ° C.

In a round four-necked flask of 250 cm3 purged with nitrogen, 120 cm3 of Isopar-L and 12.0 g of the solid component previously prepared were introduced at 25 ° C. Under stirring, the temperature rose to 130 ° C in 45 minutes and was maintained for 5 hours. Subsequently, the temperature decreased to 80 ° C, stirring was stopped, the solid product was allowed to stand for 30 minutes and the supernatant was obtained. The solid was washed twice with 100 cm3 of each of the anhydrous hexanes at 25 ° C. Finally, the solid was dried under vacuum and analyzed. The results are reported in table 1.

EXAMPLE 2

a) In a 1L round four-necked flask, purged with nitrogen, 715 mL of TiCl4 and 6.30 g of anhydrous AlCl3 were introduced at 25 ° C and cooled to 0 ° C. Subsequently, at the same temperature, 56.5 g of a spherical MgCl2 / EtOH adduct containing 25% by weight of ethanol were added and prepared as described above under stirring. The temperature rose to 135 ° C in 120 minutes and was maintained for 120 minutes. Subsequently, the temperature decreased to 130 ° C, stirring was stopped, the solid product was allowed to stand for 30 minutes and the supernatant was obtained. The solid residue was subsequently washed five times with hexane at 60 ° C, once at room temperature and dried under vacuum at 30 ° C.

b) In a round four-necked 300 cm3 nitrogen purged flask, 100 cm3 of anhydrous heptane and 10.9 g of the solid component previously prepared were introduced at 25 ° C. Under stirring, the temperature rose to 98 ° C in 20 minutes and was maintained for 3 hours. Subsequently, the temperature decreased to 90 ° C, it was interrupted

Stirring, the solid product was allowed to stand for 30 minutes and the supernatant was obtained. The solid was washed once with 100 cm3 of anhydrous hexane at 25 ° C. Finally, the solid was dried under vacuum and analyzed. The results are reported in table 1.

EXAMPLE 3

In a four-necked round flask of 250 cm3 purged with nitrogen, 92 cm3 of anhydrous heptane and 9.2 g of the solid component of Example 2a) were introduced at 25 ° C. Under stirring, the temperature rose to 90 ° C in 20 minutes and was maintained for 5 hours. Subsequently, stirring was stopped, the solid product was allowed to stand for 30 minutes and the supernatant was obtained. The solid was washed once with 100 cm3 of each of the anhydrous hexanes at 25 ° C. Finally, the solid was dried under vacuum and analyzed. The results are reported in table 1.

EXAMPLE 4 10

In a four-neck round flask of 450 mL, purged with nitrogen, 310 mL of TiCl4 and 2.35 g of anhydrous AlCl3 were introduced at 25 ° C and cooled to 0 ° C. Subsequently, at the same temperature, 21.7 g of a spherical MgCl2 / EtOH adduct containing 25% by weight of ethanol were added and prepared as described above under stirring. The temperature rose to 135 ° C in 100 minutes and was maintained for 120 minutes. Subsequently, the temperature decreased to 130 ° C, stirring was stopped, the solid product was allowed to stand for 30 minutes and the supernatant was obtained. The solid residue was subsequently washed five times with hexane at 60 ° C, once at room temperature and dried under vacuum at 30 ° C.

In a round four-necked flask of 250 cm3 purged with nitrogen, 135 cm3 of Isopar-L and 13.5 g of the solid component previously prepared were introduced at 25 ° C. Under stirring, the temperature rose to 170 ° C in 45 minutes and was maintained for 1 hour. Subsequently, the temperature decreased to 80 ° C, stirring was stopped, the solid product was allowed to stand for 30 minutes and the supernatant was obtained. The solid was washed twice with 100 cm3 of each of the anhydrous hexanes at 25 ° C. Finally, the solid was dried under vacuum and analyzed. The results are reported in table 1.

EXAMPLE 5

a) In a 1.5 L four-necked glass reactor, purged with nitrogen, 950 mL of TiCl4 and 7.07 g 25 of anhydrous AlCl3 were introduced at 25 ° C and cooled to 0 ° C. Subsequently, at the same temperature, 66.8 g of a spherical MgCl2 / EtOH adduct containing 25% by weight of ethanol were added and prepared as described above under stirring. The temperature rose to 135 ° C in 100 minutes and was maintained for 120 minutes. Subsequently, the temperature decreased to 130 ° C, stirring was stopped, the solid product was allowed to stand for 30 minutes and the supernatant was obtained. The solid residue was subsequently washed five times with hexane at 30 60 ° C, once at room temperature and dried under vacuum at 30 ° C.

b) In a round four-necked 200 cm2 nitrogen-purged flask, 110 cm3 of anhydrous isopar-L and 11.1 g of the solid component previously prepared in a) were introduced at 25 ° C. Under stirring, the temperature rose to 130 ° C in 30 minutes and was maintained for 5 hours. Subsequently, the temperature decreased to 80 ° C, stirring was stopped, the solid product was allowed to stand for 30 minutes and the supernatant was obtained. Solid 35 was washed three times with 100 cm 3 of each of the anhydrous hexanes at 25 ° C. Finally, the solid was dried under vacuum and analyzed. The results are reported in table 1.

EXAMPLE 6

a) In a 1.5 L four-necked glass reactor, purged with nitrogen, 1 L of TiCl 4 was introduced at 25 ° C and cooled to 0 ° C. Subsequently, at the same temperature, 12.5 g of anhydrous AlCl 3 and 100 g of a spherical MgCl 2 / EtOH adduct containing 25% by weight of ethanol were added and prepared as described above under stirring. The temperature rose to 135 ° C in 120 minutes and was maintained for 120 minutes. Subsequently, the temperature decreased to 130 ° C, stirring was stopped, the solid product was allowed to stand for 60 minutes and the supernatant was obtained. The solid residue was subsequently washed seven times with hexane at 60 ° C and dried under vacuum at 30 ° C. Four. Five

b) The solid product obtained was introduced into a round four-necked 1000 cm3 flask, purged with nitrogen and connected to a "rotary evaporator" system maintained in a nitrogen atmosphere. The oil bath temperature was set at 145 ° C and the rotational speed of the rotary evaporator was set at 70 rpm. Subsequently, keeping the flask in rotation it was submerged in the oil bath. In about 20 minutes, the internal temperature rose to 140 ° C and was maintained for 2 hours. In the end, the temperature decreased to 25 ° C and the solid was analyzed. The 50 results are reported in table 1.

EXAMPLE 7

In a 1.5 L four-necked glass reactor, purged with nitrogen, 1 L of TiCl 4 was introduced at 25 ° C and cooled to 0 ° C. Subsequently, at the same temperature, 100 g of a spherical MgCl2 / EtOH adduct containing 55 g were added.

25% by weight ethanol and were prepared as described above under stirring. The temperature rose to 130 ° C in 90 minutes and subsequently decreased to 80 ° C. With the temperature maintained at 80 ° C, 12.5 g of anhydrous AlCl 3 was added under stirring. The temperature was raised again to 135 ° C in 40 minutes and kept under continuous stirring for 5 hours. Subsequently, the temperature decreased to 90 ° C, stirring was stopped, the solid product was allowed to stand for 30 minutes and the supernatant was obtained. The solid residue was subsequently washed seven times with hexane at 60 ° C and dried under vacuum at 30 ° C and analyzed. The results are reported in table 1.

EXAMPLE 8

In a 500 cm3 four-necked glass reactor, purged with nitrogen, 300 cm3 of TiCl4 was introduced at 25 ° C and cooled to 0 ° C. At the same temperature, 2.6 g anhydrous AlCl 3 and 20.8 g of a spherical adduct of 10 MgCl 2 / EtOH containing 25% by weight of ethanol were added and prepared as described above under stirring. The temperature rose to 135 ° C in 110 minutes and was maintained under continuous stirring for 2 hours. Subsequently, the temperature decreased to 130 ° C, stirring was stopped, the solid product was allowed to stand for 30 minutes, the supernatant liquid was obtained and the solid residue was washed four times with heptane at 90 ° C. At the end 200 cm3 of heptane were introduced, the temperature was raised to 97 ° C and maintained for 5 hours under continuous stirring. Subsequently, stirring was stopped, the solid product was allowed to stand for 30 minutes and the supernatant liquid was removed. The solid residue was subsequently washed four times with hexane at 60 ° C and dried under vacuum at 30 ° C and analyzed. The results are reported in table 1.

EXAMPLE 9

a) In a four-necked glass flask of 2 L, purged with nitrogen, 1 L of TiCl4 was introduced at 0 ° C. Subsequently, at the same temperature, 70 g of a spherical MgCl 2 / EtOH adduct containing 25% by weight of ethanol were added and prepared as described above under stirring. The temperature rose to 140 ° C in 2 hours and was maintained for 60 minutes. Subsequently, stirring was stopped, the solid product was allowed to stand and the supernatant liquid was removed. The solid residue was subsequently washed once with heptane at 80 ° C and five times with hexane at 25 ° C and dried under vacuum at 30 ° C. 25

b) In a round four-necked 350 cm3 flask, purged with nitrogen, 220 cm3 of TiCl4 and 2.29 g of anhydrous AlCl3 were introduced at 25 ° C and cooled to 0 ° C. Subsequently, at the same temperature, 21.5 g of solid component a) previously prepared under stirring were added. The temperature rose to 135 ° C in 45 minutes and was maintained for 5 hours. Subsequently, the temperature decreased to 80 ° C, stirring was stopped, the solid product was allowed to stand for 30 minutes and the supernatant liquid was removed. The solid was washed five times with hexane at 60 ° C and once at 25 ° C. Finally, the solid was dried under vacuum and analyzed. The results are reported in table 1.

EXAMPLE 10

In a round four-necked 200 cm3 nitrogen-purged flask, 75 cm3 of anhydrous isopar-L, 1.9 g of anhydrous AlCl3 and 15.0 g of the solid component of Example 9 a) previously prepared, at 25 ° were introduced C. Under stirring, the temperature rose to 150 ° C in 30 minutes and was maintained for 1 hour. Subsequently, the solid product was allowed to stand for 30 minutes and the supernatant liquid was removed. The solid was washed with 100 cm 3 of heptane at 90 ° C and three times with anhydrous hexane at 25 ° C. Finally, the solid was dried under vacuum and analyzed. The results are reported in table 1.

EXAMPLE 11 40

a) In a 1.5 L four-necked glass reactor, purged with nitrogen, 1 L of TiCl 4 was introduced at 25 ° C and cooled to 0 ° C. Subsequently, at the same temperature, 10.9 g anhydrous AlCl 3 and 100 g of a spherical MgCl 2 / EtOH adduct containing 25% by weight of ethanol were added and prepared as described above under stirring. The temperature rose to 135 ° C in 120 minutes and was maintained for 120 minutes. Subsequently, the temperature decreased to 130 ° C, stirring was stopped, the solid product was allowed to stand for 60 minutes and the supernatant liquid was removed. The solid residue was subsequently washed seven times with hexane at 60 ° C, once at room temperature and dried under vacuum at 30 ° C.

b) 10 g of the solid product obtained and 100 ml of hexane were placed at room temperature in a four-necked 250 250 cm3 glass autoclave, purged with nitrogen. The autoclave was closed, the internal temperature was raised to 100 ° C and maintained for 5.5 hours. At the end, the temperature decreased to 55 ° C, stirring was stopped, the solid product was allowed to stand for 10 minutes and the supernatant liquid was removed. The solid was washed with hexane at 25 ° C and dried under vacuum at 30 ° C and analyzed. The results are reported in table 1.

EXAMPLE 12

In a round four-necked 200 cm3 nitrogen-purged flask, 75 cm3 of heptane were introduced 55

anhydrous, 17.2 ml of a heptane solution containing 14.2 mmol of anhydrous AlCl2 and 15.2 g of the solid component of Example 9 a) previously prepared, at 25 ° C. Under stirring, the temperature rose to 80 ° C in 20 minutes and was maintained for 3 hours. Subsequently, the solid product was allowed to stand for 30 minutes and the supernatant liquid was removed. The solid was washed with 100 cm 3 of heptane at 80 ° C and three times with anhydrous hexane at 25 ° C. Finally, the solid was dried under vacuum and analyzed. The results are reported in table 1. 5

EXAMPLE 13

The catalyst component was prepared in accordance with the same procedure disclosed in Example 7 with the difference that AlI3 was used in a Mg / Al molar ratio of 7: 3 instead of AlCl3. The results of the characterization are reported in table 1.

EXAMPLE 14 10

In a 500 mL round four-necked flask equipped with a mechanical stirrer and purged with nitrogen, 200 mL of anhydrous heptane and 2 g of solid catalyst component were obtained as disclosed in Example 7 at room temperature. At the same temperature, with stirring, an amount of acetylacetone was added to reach an ED / Ti molar ratio of 0.5 in drops. The temperature was raised to 50 ° C and the mixture was stirred for 3 hours. Subsequently, stirring was stopped, the solid product was allowed to stand and the supernatant was obtained. fifteen

The solid was washed 3 times with anhydrous hexane (3 x 100 mL) at 25 ° C, recovered, dried in vacuo and analyzed. The final donor content was 0.1%. The polymerization results obtained through its use in the ethylene polymerization processes A and B described above are reported in Table 2.

EXAMPLE 15

The catalyst component was prepared as described in example 14 with the difference that the temperature of the treatment was 100 ° C. No donor was found in the final solid catalyst component. The polymerization results obtained by use in the ethylene B polymerization process described above are reported in Table 2.

EXAMPLE 16

The catalyst component was prepared as described in example 14 with the difference that 9,9-bis (methoxymethyl) fluorene was used instead of acetylacetone. The final donor content was 1.2%. The polymerization results obtained through its use in the ethylene polymerization processes A and B described above are reported in Table 2.

EXAMPLE 17

The catalyst component was prepared as described in example 16 with the difference that the temperature of the treatment was 100 ° C. The final donor content was 1.2%. The polymerization results obtained through its use in the ethylene polymerization processes A and B described above are reported in Table 2.

EXAMPLE 18

The catalyst component was prepared as described in example 14 with the difference that 9,9-dimethoxyfluorene was used instead of acetylacetone. The final donor content was 0.1%. The polymerization results obtained by use in the ethylene A polymerization process described above are reported in Table 2.

Comparative Example 1

The catalyst was prepared as described in example 1 without using AlCl3. The results are reported in table 1. 40

EXAMPLE 19

Preparation of PE with broad MWD in a cascade polymerization process

The polymerization process was carried out in a plant in continuous operation and basically equipped with a small reactor (pre-contact crucible) in which the catalyst components were mixed to form the catalytic system, a second vessel that receives the catalytic system formed in the previous stage also equipped with mixing means, and two fluidized bed reactors (polymerization reactor) that are maintained under propane fluidization conditions.

The following reactors are fed with the pre-contact crucible:

▪ the solid catalyst component prepared as described in example 7

▪ liquid propane as diluent

▪ a solution of alkyl aluminum compound

The temperature is in the range of 10 to 60 ° C and the residence time (first and second container) ranges between 15 minutes and 2 hours. The catalyst system thus obtained was fed directly from the pre-contact section (the first and the second vessel) to the gas phase fluidized bed reactor operated under conditions reported in Table 1. The polymer produced in the first phase reactor gas was subsequently transferred to a second gas phase reactor operating under conditions reported in Table 3.

The polymer discharged from the final reactor was first transferred to the vaporization section and subsequently dried at 70 ° C under nitrogen flow and weighed. The properties of the polymer are reported in table 4.

EXAMPLE 20 10

The polymerization was carried out as described in example 19 with the difference that the catalyst prepared in accordance with the disclosure of example 17 was used. The results and conditions are reported in Tables 3 and 4.

Table 1

 Example

                      Porosity (Hg method)

 Mg Ti Al Cl ORI Factor LA LA / (Al + Ti) PF

 % by weight% by weight% by weight% by weight% by weight cm3 / g

 one

 18.5 5.2 1.3 67.1 0.3 1.84 1.28 0.611

 2

 17.5 5.7 2.1 65.8 1.4 2.21 1.33 0.534

 3

 17.7 5.7 2.2 67.1 1.8 2.08 1.23 0.599

 4

 18.3 4.7 2.1 65.9 <0.1 2.77 1.53 0.566

 5

 17.7 5.0 2.0 65.3 0.3 2.41 1.41 0.558

 6

 17.4 6.4 2.3 65.0 0.4 2.83 1.72 0.555

 7

 17.4 6.2 2.2 66.3 0.5 2.45 1.49 0.544

 8

 17.1 5.5 2.5 65.5 0.9 2.37 1.31 0.526

 9

 18.4 4.2 2.1 68.9 <0.1 1.77 0.94 0.515

 10

 17.7 4.0 2.5 63.0 1.0 3.27 1.63 0.502

 eleven

 18.2 4.9 2.1 65.4 2.5 2.39 1.35 0.532

 12

 17.9 5.1 2.1 64.7 - 0.530

 13

 16.6 5.4 2.8 66.9 - 1.79 0.94 0.526

 Comp. one

 19.0 6.4 66.7-1.43 0.643

Table 2 15

 Example

 Pol. Procedure Performance MIE BDP Polymer morphology

 KgPE / heat dg / min g / cm3

 one

 A 5.5 114 0.378 spherical

 2

 At 9.2 0.355 spherical

 3

 A 7.6 0.342 spherical

 4

 A 5.0 70 0.405 spherical

 5

 A 5.2 70 0.392 spherical

 6

 A 4.1 41 0.406 spherical

 7

 A 5.7 162 0.379 spherical

 8

 A 7.6 0.380 spherical

 9

 A 5.1 106 0.346 spherical

 10

 At 4.3 0.364 spherical

 eleven

 A 6.8 139 0.347 spherical

 12

 A 4.1 84 0.356 spherical

 13

 At 8.8 110 0.365 spherical

 14

 A 4.1 74 0.402 spherical

 B 3.2 95 0.3 spherical / broken

 fifteen

 B 2.9 95 0.34 spherical with broken part

 16

 A 5.2 122 0.4 spherical

 B 3.6 122 0.26 spherical / broken

 17

 A 4.4 115 0.399 spherical

 B 5.4 135 0.345 spherical

 18

 A 5.8 108 0.393 spherical

 Comp. one

 A 13.6 113 0.269 broken

Table 3

 Pre-contact

 1st container

 2nd container

 Cat. (G / h)

 Type AlR3 AlR3 / Cat. (G / g) Time (min.) T (° C) Time (min.) T ° (° C)

 10

 TiBA 5 14 50 60 50

 10

 TiBA 4 14 50 60 50

 First fluidized bed reactor

 C2 - (% mol)

 H2 / C2 - (mol Time (hr) P barg T (° C) Performance (Kg / h)

 9.3

 3.8 1.6 24 75 70

 7.8

 3.9 2.0 24 75 66

 Second fluidized bed reactor

 Time (hr)

 T (° C) P barg C2H4 (% mol) H2 / C2 - (mol) C6- / C2 + C6- (mol) Yield (Kg / h)

 1.6

 75 24 4.4 0.061 0.070 153

 1.8

 85 24 6.0 0.065 0.068 145

Table 4 - Final Polymer

 19 20

 MIP (g / 10 ')

 0.29 0.28

 MIF / MIP

 37.9 29.7

 Bulk Density (Kg / dm3)

 0.463 0.487

 Gel number

 <0.2

 170 120

 0.5 ÷ 0.7

 3 8

 0.7 ÷ 1.5

 0 0

 > 1.5

 0 0

Claims (15)

1. The catalyst components for the polymerization of olefins comprising Ti, Mg, Al, Cl and optionally ORI groups where RI is a C1-C20 hydrocarbon group, optionally containing heteroatoms, up to such an amount to produce an OR '/ molar ratio Ti less than 0.5, characterized by the fact that at least 95% of Ti atoms are in a valence state of 4, than the porosity (PF), measured by the mercury method and by the pores with an equal radius or less than 1µm, it is at least 0.3 cm3 / g, and due to the fact that the molar ratio Cl / Ti 5 molar is less than 29. 2. The solid catalyst component according to claim 1 wherein the porosity (PF) is greater than 0.40 cm3 / g. 3. The solid catalyst component according to claim 1 wherein the Cl / Ti molar ratio is less than 28. 10 4. The solid catalyst component according to claim 1 wherein the amount of Al is less than that of Ti. 5. The solid catalyst component according to claim 1 characterized by a "LA factor" greater than 0.5 wherein the "LA factor" is the molar equivalent of missing anionic species to satisfy all molar equivalents of the cations present in the solid catalyst component that have not been satisfied by the total molar equivalent of anions present in the solid catalyst component, all molar equivalents of anions and cations are called the molar amount of Ti. 6. The catalyst component according to claim 1 characterized by the LA / Al + Ti ratio, wherein Al and Ti are reported in a molar amount referred to the molar amount of Ti, greater than 0.5. 7. The solid catalyst component according to claim 1 containing aluminum chloride 20 selected from the groups consisting of aluminum compounds of formula AlClL2 wherein L may independently be ORI groups as defined in claim 1 or chlorine. 8. A process for the preparation of the catalyst component according to claim 1 comprising a step (a) in which a compound MgCl2.mRIIOH tH2O, where 0.3 ≤ m ≤ 1.7, t ranges between 0.01 and 0.6, and RII is an alkyl, cycloalkyl or aryl radical having between 1 and 12 carbon atoms, reacts with a titanium compound of formula Ti (ORI) nXy-n, in which n ranges from 0 to 0.5, and is the valence of titanium, X is halogen and RI is as defined in claim 1, in the presence of an aluminum compound of formula AlL3 wherein L may independently be ORI groups where RI is a C1-C20 hydrocarbon or halogen group. 9. The process according to claim 8 comprising a second stage (b) in which the solid product recovered from step (a) is subjected to a heat treatment carried out at temperatures greater than 50 ° C. 10. The process for the preparation of the catalyst component according to claim 8 comprising a second step (b) wherein the product that comes from (a) reacts again with said titanium compound in the presence of an aluminum compound of formula AlL3 where L can be, independently, ORI groups in which RI is a C1-C20 hydrocarbon or halogen group. 35 11. A process for the preparation of the catalyst component according to claim 1 comprising a step (a) in which a compound MgCl2.mRIIOH tH2O, where 0.3 ≤ m ≤ 1.7, t ranges between 0.01 and 0.6, and RII is an alkyl, cycloalkyl or aryl radical having between 1 and 12 carbon atoms, reacts with a titanium compound of formula Ti (ORI) nXy-n, in which n ranges from 0 to 0.5, and is the valence of titanium, X is halogen and RI has the assigned 40 meaning previously and a second stage (b) in which the product that comes from (a) is subjected to a heat treatment in the presence of an aluminum compound of formula AlL3 where L may independently be ORI groups in which RI is a C1- hydrocarbon group C20 or halogen. 12. The process according to any of claims 8 to 11, characterized in that a final treatment of the catalyst component is carried out comprising contacting the solid catalyst component with an electron donor compound preferably chosen from ether compounds. , ketones, esters and silicon. 13. The process for the polymerization of olefins carried out in the presence of a catalyst system comprising the reaction product of a solid catalyst component according to any one of claims 1 to 4 and an alkylaluminum compound. 14. The process according to claim 13 characterized in that it occurs in a gas phase. 15. The process according to claim 14 carried out in two or more reactors operating with different concentrations of the molecular weight regulator.