IL152167A - Process for the preparation of magnesium dichloride-alcohol adducts - Google Patents

Abstract

Process for the preparation of MgCl2OpROHOnH2O adducts, where R is a C1-C10 alkyl, 1opo6, and 0ono1, which comprises reacting MgCl2 solid particles and vaporized alcohol in a loop reactor comprising a densified zone in which the particles flow in a densified form under the action of gravity and fast fluidization zone where the particles flow under fast fluidization. 2775 י" ב בתשרי התשס" ה - September 27, 2004

Description

Process for the preparation of magnesium dichloride-alcohol adducts Montell Technology Company BV C. 141044 152167/2 "PROCESS FOR THE PREPARATION OF MAGNESIUM DICHLORIDE-ALCOHOL ADDUCTS" The present invention is divided out from IL 127230.

The present invention relates to the preparation of magnesium dichloride/alcohol adducts which . are characterized by particular chemical and physical properties. The adducts of the present invention are particularly useful as precursors of catalyst components for" the polymerization of olefins. 1 gCl2»alcohol adducts and their use in the preparation of catalyst components for the* polymerization of olefins are well known, in the art . . - J.C.J. Bart and W. oovers [Journal of Material Science, 30 (1995), 2809-2320] describe the preparation of a number of MgCla*nEtOH adducts, with n ranging from 1.4 to. 6, and their characterization by means of X-ray powder -diffraction. A range of allegedly new adducts, with n=6, 4.5, 4, 3.33, 2.5, 1.67, 1.50 and 1.25, is characterized in terms of X-ray diffraction pattern. According to the authors, the MgCla«alcohol adducts can be converted to active polymerization catalyst supports through the elimination of the alcohol molecules from the adducts by thermal desolvation. In table III of the article, the characteristic diffraction lines of the above indicated new adducts are reported with reference to the interpianar distances. For convenience, the same diffraction lines are reported below with reference to the 2Θ diffraction angles, limitatedly to the range of 2Θ diffraction angles between 5° and ° (the relative intensity I/I0 with respect to the most intense diffractio line is reported in brackets) . For n=1.25: 29=7.6° (100), 12.28° (25), 14.9° (8); for n=1.5: 20=8.44 (100), 11.95 (48), 14.2 (46); for n=1.67: 2θ=6.1° (9), 6.68° (100), 8.95° (50), 9.88° (33), 11.8° (8), 12.28° (33), 14.5° (13)," 14.75° (4); for n=2.5: 29=6.3 (27), 9.4° (100), 9.93° (70), 11.7° (11), 12.35° (6), 14.9° (6) ; ' for n=3.33 : 29=9.14° (15), 9.44° (100), 11.88° (15), 12.9° (27); for n=4: 29=8.7° (49), .1° (73), 10.49° (100), 11.8° (58); for n=4.5: 29=9.65° (100), 11.4° (10), 12.5° (24), 12.94° (32), 14.25° (20), 14.95° (6) ; for n=6: 29=8.94° (100), 13.13° (3). A MgCla*2EtOH«0.5H,0 adduct is also reported, the diffraction lines of which in the relevant range are the following: 29=7.9° (35); 8.5° (>100) ; 9.7° (26); 11.32° (100); 12.59° (11); 13.46° (12).

Catalyst components for the polymerization of olefins, obtained by reacting MgCljenEtOH adducts with halogenated transition metal compounds , are described in US? 4,399,054. The adducts are prepared by emulsifying the molten adduct in an immiscible dispersing medium and quenching the emulsion in a cooling fluid to collect the adduct in the form of spherical particles . No X-ray characteristics of the adducts are reported.

USP 4,421,674 corresponding to IL 82230 describes a method for preparing a catalyst component for the polymerization of olefins which involves the preparation of MgCl2»EtOH adducts by means of the following steps: (a) preparation of a MgCl2 solution in ethanol; (b) spray-drying said solution to collect particles of the adduct in spherical form, said adduct having from 1.5 to 20% by weight of residual alcoholic hydroxyl content and being characterized by an X-ray spectrum in which the maximum peak at 2.56 '(i.el 28=35°) characteristics of the crystalline anhydrous MgCl2 is practically absent and a new maximum peak at about 10.8 (i.e. 29=8.15°) is present; lesser peaks at about 9.16 (i.e. 26=9.65°) and 6.73 (i.e. 26=13.15°) are also reported.

EP-A-700936 describes a process for producing a solid catalyst component for the polymerization of olefins which comprises the preparation of MgCl,»EtOH adducts by means of the following steps: (A) preparation of a mixture having formula MgCla*mROH, wherein R is an alkyl group with 1 to 10 carbon atoms and m=3.0 to 6.0; (B) spray-cooling said mixture to obtain a solid adduct having the same composition as of the starting mixture; (C) partl removing the alcohol from the above-obtained solid adduct to obtain an adduct containing from 0.4 to 2.8 mol of alcohol per mol of MgCla. The adduct obtained in (C) is characterized by an X-ray diffraction spectrum in which a novel peak does not occur at a diffraction angles 28= 7 to 8° as compared with the diffraction spectrum of the adduct obtained in (B) , or even if it occurs, the intensity of the novel peak is 2.0 times or less the intensity of the highest peak present at the diffraction angles 28=8.5 to 9° of the diffraction spectrum of the adduct obtained in (C) . Fig. 2 of the said European Patent Application shows a typical X-ray diffraction spectrum of the adducts prepared in (B) . The highest peak occurs at 29=8.8°; two less intense peaks occur at 2θ=9.5 to 10° and 29=13°, respectively. Fig. 3 shows a typical X-ray diffraction spectrum of the adducts prepared in (C) . The highest peak occurs at 29=8.8°; other peaks occur at 29=6.0 to 6.5°, 29=9.5 to 10° and 29=11 to 11.5°. Fig. 4 shows a typical X-ray diffraction spectrum of comparative adducts prepared in (C) . The highest peak occurs at 29=7.6°; other peaks occur at 29=8.8°, 29=9.5 to 10°, 29=11 to 11,5° and 29=12 to 12.5°.

IL 127230 describes a new MgCla*alcohol adduct which is characterized by a particular X-ray diffraction spectrum, not shown by the adducts of the prior art, and/or by a particular crystallinity as shown by the Differential Scanning Calorimetry (DSC) profile of the adduct. In addition, particular MgCValcohol adducts of the IL 127230 can be characterized by their viscosity values in the molten state which, for a given alcohol content, are higher than the viscosity values of the corresponding adducts of the prior art. In addition to the alcohol, minor amounts of water can also be present in the adducts according to IL 127230 .

F 3/01630 The adducts IL 127230 ; can be used to prepare catalyst components for the polymerization of olefins by reactio with transition metal compounds. Catalyst components obtained from the adducts of IL 127230 are capable to give catalysts for the polymerization of olefins characterized by enhanced activity and stereospecificity with respect to the catalysts prepared from the adducts of the prior art. Also, the morphological properties of the obtained polymers are . improved, particularly when adducts in spherical forms are used.

IL 1 27230 therefore relates to Mgx:i.»nteOH«r-¾0 adducts, where R is a C,-C10 alkyl, 2 The above described diffraction pattern is unique and it has never been described in the prior art. In fact,' none of the spectr reported in Bart et al. corresponds to the spectrum which characterizes the adducts of IL 127230 ; ^ε same applies to the adducts disclosed in EP-A-700936 As for the .adducts described in USP 4,399,054, applicants repeated the preparation of the adducts according to the procedure described therein. The X-ray diffraction spectrum of the obtained adduct shows, in the range of 2Θ diffraction angles between 5 and 15°, the following main peaks (the relative intensity I/I0 with respect to the most intense diffraction line is in brackets): 28=8.84° (79); 29=9.2 (100); 29=9.43. (68); 29=9.82 (19). Contrary to the adducts of IL 127230, which are characterized, inter alia, by a most intense diffraction line occurring at 28=8.8 ± 0.2°, the adducts of USP 4,399,054 are characterized by a most intense diffraction line at 28=9.2°.

Preferably R is a Cx-Ct alkyl, more preferably ethyl, m is between 2.2 and 3.8, more preferably between 2.5 and 3.5, n is between 0.01 and 0.6, more preferably between 0.001 and 0.4. The X-ray diffraction spectra are determined with reference to the main diffraction lines of silicon, used as an internal standard, using the apparatus and the methodology described hereinafter.

The preferred adducts of the IL 127230, are characterized by an X-ray diffraction spectrum in which the intensity of the diffraction lines at 28=9.4° ± 0.2° and 9.8° ± 0.2° is at least 0.4 times, preferably at least 0.5 times the intensity of the most intense diffraction line at 28=8.8° ± As an alternative, or in addition to the X-ray spectrum, the adducts of the present invention are characterized by a Differential Scanning Calorimetry (DSC) profile in which no peaks are present at temperatures below 90°c or, even if peaks are present below said temperature, the fusion enthalpy associated with said peaks is less than 30% of the total fusion enthalpy.

The DSC analysis ' is carried out using the apparatus and the methodology described hereinafter.

When R is ethyl, m is between 2.5 and 3.5 and n is between 0 and 0.4, the fusion enthalpy associated with peaks possibly present at temperatures below 90°C is less than 10% of the total fusion enthalpy. In said case the adducts are furthermore characterized by the fact that the maximmi peak occurs at temperatures between 95 and 115°C.

Particularly preferred are adducts of the formula (I) MgClj-mEtOHe HjO (I) where m is between 2.2 and 3.8 and n is between 0.01 and 0.6, having both the above described X-ray spectrum and the above described DSC features. Adducts of this type can be further characterized by their viscosity in the molten state. In fact, it has been unexpectedly found that adducts with the above described features are also characterized by values of viscosity which, for a given alcohol content, are higher than 152167/2 the values of viscosity of the corresponding adducts of the prior art. In particular, on a plot, viscosity vs. EtOH molar content, the values of viscosity at 115°C (expressed in poise) of the adducts (I) are above the straight line passing through the points having, respectively, a viscosity/EtOH molar content of 2.43/2.38 and 1.26/3.31; at 120° the values of viscosity of the adducts (I) are above the straight line defined by the points having viscosity/EtOH molar content values of 1.71/2.38 and 0.9/3.31; at 125° the values of viscosity of the adducts (I) are above the straight line passing through the points defined by the viscosity/EtOH molar content values of 1.2/2.38 and 0.63/3.31.

The adducts of IL 127230 can be prepared with new methods, not disclosed in the prior art, which are characterized by particular modalities of reaction between MgCla, alcohol, and optionally water.

According to one ofthese methods, claimed in the Aplln.152166, MgCl2*pROH»nH20 adducts, where Risa Cj-Ci0 alkyl, 1¾>≤6, 0≤n≤l, are prepared by dispersing the particles of magnesium dichloride in an inert liquid immiscible with and chemically inert to the molten adduct, heating the system at temperature equal to or higher than the melting temperature of MgCla*alcohol adduct and then adding the desired amount of alcohol in vapour phase. The temperature is kept at values such that the adduct is completely melted.

The molten adduct is then emulsified in a liquid medium which is immiscible with and chemically inert to it and then quenched by contacting the adduct with an inert cooling liquid, thereby obtaining the solidification of the adduct.

The liquid in which the MgCl2 is dispersed can be any liquid immiscible with and chemically inert to the molten adduct. For example, aliphatic, aromatic or cycloaliphatic hydrocarbons can be used as well as silicone oils. Aliphatic hydrocarbons such as vaseline oil are particularly preferred. After the MgCl2 particles are dispersed in the inert liquid, the mixture is heated at temperatures preferably higher than 125°C and more preferably at temperatures higher than 150°C. Conveniently, the vaporized alcohol is added at a temperature equal to or lower than the temperature of the mixture. Particularly preferred products obtainable with the above specified method are the adducts of formula MgCl3«mROH»nHjO, where R is a C^-C^ alkyl, 2 According to another method, claimed in the parent application 127230, the adducts ofthe invention are prepared by contacting MgCl2 and alcohol in the absence of the inert liquid dispersant, heating the system at the melting temperature of MgCl.-alcohol · adduct or above, and maintaining said conditions so as to obtain a completely melted adduct.

Said molten adduct is then emulsified in a liquid medium which is immiscible with and chemically inert to it and finally quenched by contacting the adduct with an inert cooling liquid thereby obtaining the solidification of the adduct. In particular, the adduct is preferably kept at a temperature equal to or higher than its melting temperature, under stirring conditions, for a time period equal to or greater t-h«" 10" hours, preferably from 10 to 150 hours, more preferably from 20 to 100 hours. Alternatively, in order to obtain the solidification of the adduct, a spray-cooling process of the molten adduct can be carried out.

The catalyst components obtained from the adducts obtained with the above described processes show still more improved properties over the catalyst components prepared by the adducts which have been obtained with the same preparation method but without having been maintained for the requested period of time under the described conditions.

The present invention provides amethod forpreparing gC-2*pROHnH20 adducts, where R is a Cx-C„ alkyl, 2≤p≤6, 0≤n≤l, comprises . reacting the MgCl2 solid particles and vaporized alcohol in a loop reactor comprising a densified zone in which the particles flow in a densified form under the action of gravity and a fast fluidization zone where the particles flow ■ under fast fluidization conditions. As it is known, the state of fast fluidization is obtained when the velocity of the fluidizing gas is higher than the transport velocity, and it is characterized in that the pressure gradient along the direction of transport is a monotonic function of the quantity of injected solid, for equal flow rate and density of the fluidizing gas. The terms transport velocity and fast fluidization state are well known in the art; for a definition thereof, see, for example, "D. Geldart, Gas Fluidizatio Technology, page 155 et seqq., J.Wiley & Sons Ltd., 1986". In the second polymerization zone, where the particles flows in a densified form under the action of gravity, high values of density of the solid are reached (density of the solid = kg of solid particles per m3 of reactor occupied) , which approach the bulk density of the adduct; a positive gain in pressure can thus be obtained along the direction of flow, so that it becomes possible to reintroduce the solid particles into the fast fluidization zone without the help of special mechanical means. In this way, a "loop" circulation is set up, which is defined by the balance of pressures between the two zones of the reactor.

In particular, the above method is suitable to prepare MgCljemROHe HjO adducts, where R is a C^C^ alkyl, 2 The particles of the adduct discharged from the loop reactor can be then subjected to a treatment capable of imparting them a spherical morphology. In particular, the treatment comprises subjecting the adducts to a temperature equal to or higher than the melting temperature of the adduct until the adduct is completely melted, said treatment being carried out in absence or presence of an inert liquid dispersant, then emulsifying the molten adduct in a liquid medium which is immiscible with and chemically inert to it and finally quenching the molten adduct with an inert cooling liquid thereby obtaining the solidification of the adduct in spherical form. Alternatively, in order to obtain the solidification of. the adduct in spherical form, the molten adduct can be subjected to a spray-cooling process according to known techniques.

The treatment which comprises melting the adduct in the presence of an inert dispersant agent, such as vaseline oil, then emulsifying and finally quenching said molten adduct, is particularly preferred.

The liquid in which the molten adduct is emulsified is preferably a hydrocarbon liquid such as vaseline oil. The liquid used to quench the emulsion can be equal to or different from the liquid in which the molten adduct is emulsified. Preferably, it is an. aliphatic hydrocarbon and more preferably a light aliphatic hydrocarbon such as pentane, hexane, heptane and the like.

The solid adducts having a spherical morphology are very suitable in the preparation of spherical catalyst components fo the polymerization of olefins and in particular for the gas-phase polymerization process.

The catalyst components to be used in the polymerization of olefins comprise a transition metal compound of one of the groups IV to VI of the Periodic Table of Elements, supported on the adducts of IL 127230.

A method suitable for the preparation of said datalyst components, comprises the reaction between the adducts of the invention and the transition metal compound. Among transition metal compounds particularly preferred are titanium compounds of formula Ti (OR)^.,, in which n is comprised between 0 and y; y is the valency of titanium; X is halogen and R is an alkyl radical having 1-8 carbon atoms or a COR group. Among them, particularly preferred are titanium compounds having at least one Ti-halogen bond such as titanium tetrahalides' o halogenalcoholates . Preferred specific titanium compounds are TiCl3, TiCl4, Ti(0Bu)4, Ti(0Bu)Cl3, Ti(OBu)2Cl,, Ti(0Bu).Cl. Preferably the reaction is carried out by suspending the adduct in cold TiCl4 (generally OEC) ; then the so obtained mixture is heated up to 80-13OEC and kept at this temperature for 0.5-2 hours. After that the excess of TiCl4 is removed and the solid component is recoverd. The treatment with TiCl4 can be carried out one or more times.

The reaction between transition metal compound and the adduct can also be carried out in the presence of an electron donor compound (internal donor) in particular when the preparation of a stereospecic catalyst for the polymerization of olefins is to be prepared. Said electron donor compound can be selected from esters, ethers, amines, silanes and ketones. In particular, the alkyl and aryl esters of mono or polycarboxylic acids such as for example esters of benzoic, phthalic and malonic acid, are preferred. Specific examples of such esters are n- butylphthalate, di-isobutylphthalate, di-n-octylphthalate, ethyl-benzoate and p-ethoxy ethyl-benzoate . Moreover, can be advantageously used also the 1,3 diethers of the formula: wherein R1, R", RM, R17, RV and R" equal or different to each other, are hydrogen or hydrocarbon radicals having from 1 to 18 carbon atoms, and RTO and R7111, equal or different from each other, have the same meaning of RI-RVI except that they cannot be hydrogen; one or more of the RT-RRAX groups can be linked to form a cycle. The 1,3-diethers in which R*11 and R*111 are selected from C4-C4 alkyl radicals are particularly preferred.

The electron donor compound is generally present in molar ratio with respect to the magnesium comprised between 1:4 and 1:20. Preferably, the particles of the solid catalyst components have substantially spherical morphology and an average diameter comprised between 5 and 150μχα. With the term substantial spherical morphology are meant those particles having a ratio between the greater and smaller axis equal to or lower than 1.5 and preferably lower than 1.3.

Before the reaction with the transition metal compound, the adducts of IL 127230 1 can also be subjected, to a dealcoholatio treatment aimed at lowering the alcohol content and increasing the porosity of the adduct itself. The dealcoholation can be carried out according to known methodologies such as those described in EP-A-395083. Depending on the extent of the dealcoholation treatment, partially dealcoholated adducts can be obtained having an alcohol content generally ranging from 0.1 to 2.6 moles of alcohol per mole of MgClj. After the dealcoholation treatment the adducts are reacted with the transition metal compound, according to the techniques described above, in order to obtain the solid catalyst components.

The solid catalyst components according to IL 127230 show a surface area (by B.E.T. method) generally between 10 and 500 ma/g and preferably between 20 and 350 ma/g, and a total porosity (by B.E.T.. method) higher than 0.15 cmVg preferably between 0.2. and 0.6 cmVg.

Surprisingly, the catalyst components comprising the reaction product of a transition metal compound with a MgCl2-alcohol adduct which is in turn obtained by partially dealcoholating the adducts of IL 127230, show improved properties, particularly in terms of activity, with respect to the catalyst components prepared from the dealcoholated adducts of the prior art.

The catalyst components of IL 1 27230 form catalysts for the polymerization of alpha-olefins wherein R is hydrogen or a hydrocarbon radical having 1-12 carbon atoms, by reaction with Al-alkyl compounds. The alkyl-Al compound is preferably chosen among the trialkyl aluminum compounds such as for example triethylaluminum, triisobutylaluminum, tr'i-n-" butylaluminum, tri-n-hexylaluminum, tri-n-octylaluminum. It is also possible to use alkylaluminum halides, alkylaluminum hydrides or alkylaluminum sesquichlorides such as AlEtaCl and AljEtjClj optionally in mixture with said trialkyl aluminum compounds ..

The Al/Ti ratio is higher than 1 and is generally comprised between 20 and 800.

In the case of the stereoregular polymerization of . a-olefins such as for example propylene and 1-butene, an electron donor compound (external donor) which can be the same or different from the compound used as internal donor can be used in the preparation of the catalysts disclosed above. In case the internal donor is an ester of a polycarboxylic acid, in particular a phthalate, the external donor is preferably selected from the silane compounds containing at least a Si-OR link, having the formula R.^SiiOR1),., where a and b are" integer from 0 to 2, c is an integer from 1 to 3 and the sum (a+b+c) is 4; R1, Ra, and R3, are alkyl, cycloalkyl or aryl radicals with 1- 0 18 carbon atoms. Particularly preferred are the silicon compounds in which a is 1, b is 1, c is 2, at least one of Rl and R1 is selected from branched alkyl, cycloalkyl or aryl groups with 3-10 carbon atoms and R1 is a Cx-C„ alkyl group, in particular methyl. Examples of such preferred silicon compounds are methylcyclohexyldimethoxysilane, diphenyldimethoxysilane, methyl-t-butyldimethoxysilane, dicyclopentyldimethoxysilane. Moreover, are also preferred the silicon compounds in which a is 0, c is 3, Ra is a branched alkyl or cycloalkyl group and R3 is methyl. Examples of such preferred silicon compounds are cyclohexyltrimethoxysilane, t-butyltrimethoxysilane and thexyltrimethoxysilane.

Also the 1,3 diethers having the previously described formula can be used as external donor. However, in the case 1,3-diethers are used as internal donors, the use of an external donor can be avoided, as the stereospecificity of the catalyst is already sufficiently high.

As previously indicated the components of IL 127230 and catalysts obtained therefrom find applications in the processes for the (co)polymerization of olefins of formula CH-=CHR in which R is hydrogen or a hydrocarbon radical having 1-12 carbon atoms.

The catalysts of IL 127230 ,can be used in any of the olefin polymerizatio processes known in the art. They can be used for example in slurry polymerization using as diluent an inert hydrocarbon solvent, or bulk polymerization using the liquid monomer (for example propylene) as a reaction medium. Moreover, they can also be used in the polymerization process carried out in gas-phase operating in one or more fluidized or mechanically agitated bed reactors.

The polymerization is generally carried out at temperature of from 20 to 120°C, preferably of from 40- to 80°C. When the polymerization is carried out in gas-phase the operating pressure is generally between 0.1 and 10 MPa, preferably between 1 and 5 MPa. In the bulk polymerization the operating pressure is generally between 1 and 6 MPa preferably between 1.5 and 4 MPa.

The catalysts of IL 127230 are very useful for preparing a broad range of polyolefin products. Specific examples of the olefinic polymers which can be prepared are: high density ethylene polymers (HDPE, having a density higher than 0.940 g/cc) , comprising ethylene homopolymers and copolymers of ethylene with alpha-olefins having 3-12 carbon atoms; linear low density polyethylenes (LLDPE, having a density lower than 0.940 g/cc) and very low density and ultra low density (VLDPE and ULDPE, having a density lower than 0.920 g/cc, to 0.880 g/cc) consisting of copolymers of ethylene with one or more alpha-olefins having from 3 "to 12 carbon atoms, having a mole content of units derived from the ethylene higher than 80%; isotactic polypropylenes and crystalline copolymers of propylene and ethylene and/or other alpha-olefins having a content of units derived from propylene higher than 85% by weight; copolymers of propylene and 1-butene having a content of units derived from 1-butene comprised between 1 and 40% by weight; heterophasic copolymers comprising a crystalline polypropylene matrix and an amorphous phase comprising copolymers of propylene with ethylene and or other alpha-■ olefins.

The following examples are given to illustrate and not to limit the inventio itself. cga-ZUtfy BRizA TOK The properties reported below have been determined according to the following methods: X-rav diffraction spectra were carried out with a Philips PW 1710 instrument using the CuK^X^l, 5418"?) with a 40Rv tension generator, a 20mA current generator and a receiving slit of 0.2mm. The X-ray diffraction patterns were recorded in the range between 2θ=5° and 2Θ=15° with a scanning rate of 0.05°2Θ/10 sec. The instrument was calibrated using the ASTM 27- 1402 standard for Silicon. The samples to be analyzed were closed in a polyethylene bag of- 50pm thickness operating in a dry-box.

The DSC measurement were carried out with a METTLER DSC 30 instrument at a scanning rate of 5°C/min in the range 5-125°C. Aluminum capsules having a volume of 40μ1 filled with the samples in a dry-box were used in order to avoid hydration of the samples.

The viscosity measurement have been carried out according to" ASTM D445-65 using a Cannon-Fenske type viscosimeter. During the measurement the samples are maintained in a dry nitrogen environment in order to avoid hydration. nnr¾M T.Tgg General procedure for the preparation of the catalyst component Into .a 11 steel reactor provided with stirrer, δθθαη3 of TiCl4 at 0°C were introduced; at room temperature and. whilst stirring 16 g of the adduct were introduced together with an. amount of diisobutylphthalate as internal donor so as to give a donor/Mg molar ratio of 10. The whole was heated to 100°C over 90 minutes and these conditions were maintained over 120 minutes. The stirring was stopped and after 30 minutes the liquid phase was separated from the sedimented solid maintaining the temperature at 100°C. A further treatment of the solid was carried out adding 750 COL of TiCl« and heating the mixture at 120°C over 10 min. and maintaining said conditions for 60 min under stirring conditions (500 rpm) . The stirring was then discontinued and after 30 minutes the liquid phase was separated from the sedimented solid maintaining the temperature at 120°C. Thereafter, 3 washings with 500 cm3 of anhydrous hexane at 60°C and 3 washings with 500 cm3 of anhydrous hexane at room temperature were carried out. The solid catalyst component obtained was then dried under vacuum in nitrogen environment at a temperature ranging from 40-45°C.

Ptene>ral procedure for the polymerization test A 4 litre steel autoclave equipped with a stirrer, pressure gauge, thermometer, catalyst feeding system, monomer feeding lines and hermostatting jacket, was used. The reactor was charged with 0.01 gr of solid catalyst component 0,76 g of TEAL, "0.076g of dicyclopentyl dimetoxy silane, 3.2 1 of propylene, and 1.5 1 of hydrogen. The system was heated to 70°C over 10 ntin. under stirring, and maintained under these conditions for 120 min. At the end of the polymerization, the polymer was recovered by removing any unreacted monomers and was dried under vacuum.

EXaMPLE 1 Preparation of the adduct 100 gr of MgCl, were dispersed in 1200 cm3 of OB55 vaselin oil into a vessel reactor. The temperature was raised up to 160°C and 135,2 g. of vaporized EtOH having the same temperature were slowly added to the mixture. At the end of the addition, the mixture was cooled up to 125°C and maintained at this temperature obtaining a completely melted and clear adduct.

This mixture was kept at 125° under stirring conditions by means of a Ultra Turrax T-45 type stirrer operating at 2000 rpm. Thereupon the mixture was discharged into a vessel containing hexane which was kept under stirring and cooled so that the final temperature did not exceed 12°C. The solid particles of the MgCl-»EtOH adduct recovered, containing 57% by weight of EtOH, were then washed with hexane and dried at 40°C under vacuum.

The X-ray spectrum of the adduct showed in the range of 2Θ diffraction angles between 5° and 15° three diffraction lines present at diffraction angles 2Θ of 8.80° (100), 9.40° (63) and 9.75° (54); the number in brackets represents the intensity I/I„ with respect to the most intense line.

The DSC profile showed a peak at 100.5°C and a peak at 81.4°C for a total fusion enthalpy of 107.9 J/g. The fusion enthalpy associated with the peak at 81.4°C was 6.9 J/g corresponding to 6.3% of the total fusion enthalpy. The catalyst component, prepared according to the general procedure, was tested according to the general polymerization procedure described above and gave the results reported in Table 1. 100 gr of MgCl. were introduced in a vessel reactor which contained 135,2 g of EtOH at room temperature and under stirring. Once the addition of MgCla was completed the temperature was raised up to 125°C and kept at this value for 10 hours.

The so obtained adduct was transferred in a vessel containing 1200 cm3 of OB55 vaseline oil, and kept at 125°C under stirring conditions by means of a Ultra Turrax T-45 type stirrer operating at 2000 rpm for a total time of 20 hours. Thereupon the mixture was discharged into a vessel containing hexane which was kept under stirring and cooled so that the final temperature did not exceed 12°C. The solid particles of the MgCla«EtOH adduct recovered, containing 57% by weight of EtOH, were then washed with hexane and dried at 40°C under vacuum.

The X-ray spectrum of the adduct showed in the range of 2Θ diffraction angles between 5° and 15° three diffraction lines present at diffraction angles 2Θ of 8.83° (100), 9.42° (65) and 9.80° (74); the number in brackets represents the intensity I/Ia with respect to the most intense line. The DSC profile showed a peak at 103.4°C,a peak at 97.2°C, a peak at 80.1°C and a peak at 70.2°C for a total fusion enthalpy of 101 J/g. The fusion enthalpy associated with the peaks at 80.1°C and at 70.2°C was 16.5 J/g corresponding to 16.3%. of the total fusion enthalpy.

The catalyst component, prepared according to the general procedure, was tested according to the general polymerization procedure described above and gave the results reported in Table 1.

Tgg¾MPT.T! ¾ 100 gr of MgCla were introduced in a vessel reactor which contained 135,2 g of EtOH at room temperature and under stirring. Once the addition of MgCla was completed the temperature was raised up to 125°C and the system maintained at this temperature and under stirring conditions for 70 hours. The so obtained adduct was transferred in a vessel containing 1200 cm3 of OB55 vaseline oil, and kept at 125°C under stirring conditions by means of a Ultra Turrax T-45 type stirrer operating at 2000 rpm. Thereupon the mixture was discharged "into a vessel containing hexane which was kept under stirring and cooled so that the final temperature did not exceed 12°C. The solid particles of the MgCl^EtOH adduct recovered, containing 57.4% by weight of EtOH, were then washed with hexane and dried at 40°C under vacuum.

The X-ray spectrum of the adduct showed in the range of 2Θ diffraction angles between 5° and 15° three diffraction lines present at diffraction angles 2Θ of 8.83° (100), 9.42° (64) and 9,82° (73); the number in brackets represents the intensity I/I0 with respect to the most intense line.

The DSC profile showed a peak at 105.7°C, and a peak at 64.6°C for a total fusion enthalpy of 90.3 J/g. The fusion enthalpy associated with the peak at 64.6° was of 0.7 J/g corresponding to 0.77% of the total fusion enthalpy.

The catalyst component, prepared according to the general procedure, was tested according to the general polymerization procedure described above and gave the results reported in Table 1.

In a loop reactor comprising a fast fluidization zone and a densified zone when the particles flow under the action of gravity were charged 100 g of MgCl,. Then, 135.2 g of EtOH vaporized in a oven at 180°C, were conveyed, by a dry nitrogen flow, to the cavitated zone of a Loedige type apparatus placed into the loop reactor after the densified zone and before the fast fluidization zone. The feeding of EtOH was controlled so as to maintain the temperature in the feeding zone in the range between 42 to 48°C. Once the feeding of the alcohol was completed the particles of the adduct were transferred in a vessel containing 1200 cm3 of OB55 vaseline oil, the temperature was raised up to 125°C and the system maintained under said conditions until the adduct became completely melted and clear. This mixture was kept at 125°C under stirring conditions by means of a Ultra Turrax T-45 type stirrer operating at 2000 rpm. Thereupon the mixture was discharged into a vessel containing hexane which was kept under stirring and cooled so that the final temperature did not exceed 12°C.

The solid particles of the MgCla»EtOH adduct recovered, containing 56.5% by weight of EtOH were then washed with hexane and dried at 40°C under vacuum.

The X-ray spectrum of the adduct showed in the range of 2Θ diffraction angles between 5° and 15° three diffraction lines present at diffraction angles 2Θ of 8.90° (100), 9.48° (75) and 9.84° (63); the number in brackets represents the intensity I/I„ with respect to the most intense line.

The DSC profile showed a peak at 108.2°C, and a peak at 69.1°C for total fusion enthalpy of 97.7 J/g. The fusion enthalpy associated with the peak at 69.1°C was of 3.1 J/g corresponding to 3.1% of the total fusion enthalpy.

The catalyst component, prepared according to the general procedure, was tested according to the general polymerization procedure described above and gave the results reported in Table 1.

CQMPA ISQW unrawtw.* «¾ 100 gr of MgCla were dispersed in 1200 cm3 of OB55 vaselin oil into a vessel reactor and 135,2 g of liquid EtOH were added to the mixture. At the end of the addition the temperature was raised up to 125°C and kept at this temperature for 2 hours.

The mixture was kept at 125°C -under stirring conditions by means of a Ultra Turrax T-45 type stirrer operating at 2000 rpm. Thereupon the mixture was discharged into a vessel containing hexane which was kept under stirring and cooled so that the final temperature did not exceed 12°C. The solid particles of the gCla-EtOH adduct containing 57% by weight of EtOH were then washed with hexane and dried at 0°C under vacuum.

The X-ray spectrum of the adduct showed in the range of 2Θ diffraction angles between 5° and 15° four diffraction lines present at diffraction angles 2Θ of 8.84° (79.3), 9.2° (100), 9.43° (68.2) and 9.82° (19.5); the number in brackets represents the intensity I/Io with respect to the most intense line. The DSC profile showed a peak at 99.8°C , a peak at 82.8°C, and a peak at 71.3°C for a total fusion enthalpy of 107.2 J/g. The fusion enthalpy associated with the peak at 82.8°C and the peak at 71.3°C was of 57.1 J/g corresponding to 53.2% of the total fusion enthalpy. The catalyst component, prepared according to the general procedure, was tested according to the general polymerization procedure described above and gave the results reported in Table 1.

An MgCla-EtOH adduct prepared according to the procedure of Example 2 was thermally dealcoholated until the content of EtOH reached 44% b.w. Then, the partially dealcoholated adduct -was used to prepare, according to the general procedure, the catalyst component which was then used in a polymerization test carried out according to the procedure described above. The. results are reported in Table 1.

COMPARISON EXAMPLE 7 An MgCl2-EtOH adduct prepared according to the procedure of Comparison Example 5 was thermally dealcoholated until the content of EtOH reached 44% b.w. Then, the partially' dealcoholated adduct was used to prepare, according to the general procedure, the catalyst component which was then used in a polymerization test carried out according to the procedure described above. The results are reported in Table 1. nnra.MPT.Tg a 83 gr of MgCla were introduced in a vessel reactor which contained 170 g of EtOH at -19°C and under stirring conditions. Once the addition of MgCl, was completed the temperature was raised up to 100°C and kept at this value for 5 hours.

The so obtained adduct was transferred in a vessel containing 1200 cm1 of OB55 vaseline oil, and kept at 125°C under stirring conditions by means of a Ultra Turrax T-45 type stirrer operating at 2000 rpm for a- total time of 10 hours. Thereupon the mixture was discharged into a vessel containing hexane which was kept under stirring and cooled so that th final temperature did not exceed 12°C. The solid particles of the MgCl2»EtOH adduct recovered, containing 64% by weight of EtOH, were then washed with hexane and dried at 40°C under vacuum. The DSC profile showed a peak at 100.7°C, and a peak at 56.5°C for a total fusion enthalpy of 103 J/g. The fusion enthalpy associated with the peak at 56.5°C was 12.8 J/g corresponding to 12.4% of the total fusion enthalpy. The catalyst component, prepared according to the general procedure, was tested according to the general polymerization procedure described above and gave the results reported in Table 1.

TA2LE 1 Passages of the description which are not within the scope of the claims do not constitute part of the claimed invention.

Claims (4)

152167/2 CLA IM S:

1. Process for the preparation o f MgCl2«pROH«riH20 adducts, where R is a C,-C10 alk l, l≤p≤6, and 0

2. Process according to claim 1 in which the fluidization is obtained by a flow of an inert gas, such as nitrogen, and in which the' particles of magnesium dichloride-alcohol adduct are discharged from the densified zone.

3. Process according to claim 2 in which the feeding of the alcohol is carried out with injection nozzles located in the fluidization zone of the loop reactor.

4. Process according to claim 2 in which the alcohol is fed to the loop reactor in a zone after the densified zone and before the fluidization zone. A4/ 152167/2 Process according to claim 4 in which the alcohol is fed into the cavitated zone created by a Loedige type apparatus located in the loop reactor in a zone after the densified zone and before the fluidization zone. Process according to any of the claims 1 - 5 in which 2