Title of Invention	PREPOLYMERISED CATALYST COMPONENTS FOR THE POLYMERIZATION OF OLEFINS
Abstract	The invention provides new prepolymerized catalyst components for the (co) polymerization of olefins CH2=CHR, wherein R is hydrogen or a C1-C12 alkyl group, characterized by comprising a solid catalyst component, comprising Ti, Mg, halogen and an electron donor compound, being capable of yielding, under standard polymerization conditions, a propyiene homopolymers having an insolubility in xylene at 25C higher than 90%, which is prepolymerized with ethylene to such an extent that the amount of the ethylene prepolymer is up to 100g per g of said solid catalyst component. These such catalyst components allow to obtain a high catalyst activity, a high isotactic index and are not affected by aging.

Title of Invention

PREPOLYMERISED CATALYST COMPONENTS FOR THE POLYMERIZATION OF OLEFINS

Abstract

The invention provides new prepolymerized catalyst components for the (co) polymerization of olefins CH2=CHR, wherein R is hydrogen or a C1-C12 alkyl group, characterized by comprising a solid catalyst component, comprising Ti, Mg, halogen and an electron donor compound, being capable of yielding, under standard polymerization conditions, a propyiene homopolymers having an insolubility in xylene at 25C higher than 90%, which is prepolymerized with ethylene to such an extent that the amount of the ethylene prepolymer is up to 100g per g of said solid catalyst component. These such catalyst components allow to obtain a high catalyst activity, a high isotactic index and are not affected by aging.

Full Text	"PREPOLYMERIZED CATALYST COMPONENTS FOR THE POLYMERIZATION OF OLEFINS" The present invention relates to catalyst components for the polymerization of olefins CH2 = CHR, wherein R is hydrogen or a hydrocarbon radical having 1-12 carbon atoms, the catalysts obtained therefrom and their use in the polymerization of said olefins. In particular the catalyst components of the present invention are very suitable for the preparation of crystalline propylene (co)polymers by using gas-phase, slurry or bulk (co)polymerization processes. High-yield catalyst components for the polymerization of olefins and in particular for propylene are known in the art. They are generally obtained by supporting, on a magnesium dihalide, a titanium compound and an electron donor compound as a selectivity control agent. Said catalyst components are then used together with an aluminum alkyl and, optionally, another electron donor (external) compound in the stereospecific polymerization of propylene. Depending on the type of electron donor used the stereoregularity of the polymer can vary. However, the stereospecific catalysts of interest should be able to give polypropylene (co)polymers having isotactic index, expressed in terms of xylene insolubility, of higher than 90%. Said catalyst components, and the catalysts obtained therefrom, are largely used in the plants for the (co)polymerization of propylene both operating in liquid phase (slurry or bulk) and in gas-phase. However, the use of the catalyst components as such is not completely satisfactory. Indeed, problems such as formation of polymers with irregular morphology and in particular of fines, low bulk density and low catalyst activity are experienced when plants operate with catalyst components as such. In order to solve these problems, an additional prepolymerization line may be included, in which the catalyst is prepolymerized under controlled conditions, so as to obtain prepolymerized catalysts having good morphology. After prepolymerization, the catalysts also increase their resistance in such a way that the tendency to break under polymerization conditions is decreased. As a consequence, also the formation of fines is reduced. Moreover also the activity of the catalyst and the bulk density of the final polymers results to be improved. The use of this additional line, however, makes the plant operations and design more complex and costly; in certain cases it is therefore desirable to avoid it. One of the alternative solutions is that of supplying the plants directly with a prepolymerized catalyst which can be prepared in another facility. This solution requires the preparation of a prepolymerized catalyst meeting certain requirements such as easy preparation and handling, easy stocking operability, absence or minimal reduction of activity with time (aging) preferably coupled with a basic high activity. USP 5,641,721 discloses a method for preparing a prepolymerized catalyst comprising (i) the preparation of a procatalyst composition by depositing a transition metal compound on a suitable support, (ii) mixing said procatalyst composition with a viscous substance and then prepolymerizing said procatalyst composition with a monomer in the presence of said viscous substance. The viscous substance has a viscosity of from 1000 to 15000 cP while the monomer used is propylene. Albeit it is alleged that the catalyst activity is unchanged after 5 months, it appears that the selectivity is decreased. Moreover, the prepolymerization in such a viscous substance makes the preparation of the prepolymerized catalyst complex and, in addition, leads to a low catalyst activity. It has now surprisingly been found that by carrying out the prepolymerization with a specific monomer it is possible to obtain a catalyst for the polymerization of olefins which has a high catalyst activity, a high isotactic index and which is not affected by aging. It is therefore an object of the present invention a prepolymerized catalyst component for the (co)polymerization of olefins CH2 = CHR. wherein R is hydrogen or a C1-C12 alkyl group, characterized by comprising a solid catalyst component, comprising Ti, Mg, halogen and an electron donor compound, being capable of yielding, under standard polymerization conditions, a propylene homopolymer having an insolubility in xylene at 25°C higher than 90%, which is prepolymerized with ethylene to such an extent that the amount of the ethylene prepolymer is up to 100g per g of said solid catalyst component. Preferably the amount of ethylene polymer is less than 15 g and more preferably said amount is less than 5 g per g of solid catalyst component. In particular, the catalyst components comprise a titanium compound, having at least a Ti- halogen bond and the above mentioned electron donor compound supported on a Mg halide. The magnesium halides, preferably MgCl2, in active form used as a support for Ziegler- Natta catalysts, are widely known from the patent literature. Patents USP 4,298,718 and USP 4,495,338 were the first to describe the use of these compounds in 7,iegler-Natta catalysis. It is known from these patents that the magnesium dihalides in active form used as support or co-support in components of catalysts for the polymerization of olefins are characterized by X-ray spectra in which the most intense diffraction line that appears in the spectrum of the non-active halide is diminished in intensity and is replaced by a halo whose maximum intensity is displaced towards lower angles relative to that of the more intense line. The preferred titanium compounds used in the catalyst component of the present invention are TiCl4 and TiCl3; furthermore, also Ti-haloalcoholates of formula Ti(OR)n-yXy, where n is the valence of titanium and y is a number between 1 and n, can be used. The internal electron-donor compound may be selected from esters, ethers, amines and ketones. It is preferably selected from alkyl, cycloalkyl or aryl esters of monocarboxylic acids, for example benzoic acid, or polycarboxylic acids, for example phthalic or malonic acid, the said alkyl, cycloalkyl or aryl groups having from 1 to 18 carbon atoms. Moreover, it can be also selected from 1,3-diethers of formula (I): wherein RI, RII, RIII, RIV, RV and RVI equal or different to each other, are hydrogen or hydrocarbon radicals having from 1 to 18 carbon atoms, and RVII and RVIII, equal or different from each other, have the same meaning of RI-RVI except that they cannot be hydrogen; one or more of the RI-RVIII groups can be linked to form a cycle. Particularly preferred are the 1,3-diethers in which RVII and RVIII are selected from C1-C4 alkyl radicals. Examples of preferred electron-donor compounds are methyl benzoate, ethyl benzoate, diisobutyl phthalate and 9,9-bis(methoxymethyl)fluorene. As explained above, however, the internal electron donor compound must be selected in such a way to have a final solid catalyst component capable of producing, under the standard polymerization test disclosed below, a propylene homopolymer having an insolubility in xylene at 25°C higher than 90%. The preparation of the solid catalyst component can be carried out according to several methods. According to one of these methods, the magnesium dichloride in an anhydrous state, the titanium compound and the electron donor compound of formula (I) are milled together under conditions in which activation of the magnesium dichloride occurs. The so obtained product can be treated one or more times with an excess of TiCl4 at a temperature between 80 and 135°C. This treatment is followed by washings with hydrocarbon solvents until chloride ions disappeared. According to a further method, the product obtained by co- milling the magnesium chloride in an anhydrous state, the titanium compound and the electron donor compound is treated with halogenated hydrocarbons such as 1,2- dichloroethane, chlorobenzene, dichloromethane etc. The treatment is carried out for a time between 1 and 4 hours and at temperature of from 40°C to the boiling point of the halogenated hydrocarbon. The product obtained is then generally washed with inert hydrocarbon solvents such as hexane. According to another method, magnesium dichloride is preactivated according to well known methods and then treated with an excess of TiCl4 at a temperature of about 80 to 135°C in the presence of the electron donor compound. The treatment with TiCl4 is repeated and the solid is washed with hexane in order to eliminate any non-reacted TiCl4. A further method comprises the reaction between magnesium alcoholates or chloroalcoholates (in particular chloroalcoholates prepared according to U.S. 4,220,554) and an excess of TiCl4 in the presence of an electron donor compound (I) at a temperature of about 80 to 120°C. Particularly preferred are the solid catalyst component prepared by reacting a titanium compound of formula Ti(OR)n-yXy, where n is the valence of titanium and y is a number between 1 and n, preferably TiCl4, with an adduct of formula MgCl2.pROH, where p is a number between 0,1 and 6 and R is a hydrocarbon radical having 1-18 carbon atoms. The adduct can be suitably prepared in spherical form by mixing alcohol and magnesium chloride in the presence of an inert hydrocarbon immiscible with the adduct, operating under stirring conditions at the melting temperature of the adduct (100-130°C). Then, the emulsion is quickly quenched, thereby causing the solidification of the adduct in form of spherical particles. Examples of spherical adducts prepared according to this procedure are described in USP 4,399,054. The so obtained adduct can be directly reacted with the Ti compound or it can be previously subjected to thermal controlled dealcoholation (80- 130°C) so as to obtain an adduct in which the number of moles of alcohol is generally lower than 3 preferably between 0.1 and 2.5. The dealcoholated adduct is then suspended in cold TiCl4 (generally 0°C); the mixture is heated up to 80-130°C and kept at this temperature for 0.5-2 hours. The treatment with TiCl4 can be carried out one or more times. The internal electron donor compound can be added during the treatment with TiCl4. The treatment with the electron donor compound can be repeated one or more times. The preparation of catalyst components in spherical form is described for example in European Patent Applications EP-A-395083. The solid catalyst components obtained according to the above method show a surface area (by B.E.T. method) generally between 20 and 500 nr/g and preferably between 50 and 400 nr/g, and more preferably between 100 and 400 nr/g; a total porosity (by B.E.T. method) higher than 0.2 cm3/g preferably between 0.2. and 0.6 cm3/g and more preferably from 0.3 to 0.5 cm3/g. The porosity (Hg method) due to pores with radius up to 10.000A generally ranges from 0.3 to 1.5 cm3/g. preferably from 0.45 to 1 cm3/g. A further method to prepare the solid catalyst component of the invention comprises halogenating magnesium dihydrocarbyloxide compounds, such as magnesium dialkoxide or diaryloxide, with solution of TiCl, in aromatic hydrocarbon (such as toluene, xylene etc.) at temperatures between 80 and 130°C. The treatment with TiCl4 in aromatic hydrocarbon solution can be repeated one or more times, and the internal electron donor compound is added during one or more of these treatments. In any of these preparation methods, the desired internal electron donor compound can be added as such or, in an alternative way, it can be obtained in situ by using an appropriate precursor capable to be transformed in the desired electron donor compound by means, for example, of known chemical reactions such as esterification, transesterificution etc. Generally, the internal electron donor compound is used in molar ratio with respect to the MgCl2, of from 0.01 to 1 preferably from 0.05 to 0.5. As explained above the prepolymerized catalyst component can be obtained by prepolymerizing the solid catalyst component together with ethylene. The prepolymerization is normally carried out in the presence of an Al-alkyl compound. The alkyl-Al compound (B) is preferably chosen among the trialkyl aluminum compounds such as for example triethylaluminum, triisobutylaluminum, tri-n-butylaluminum, tri-n- hexylaluminum, tri-n-octylaluminum. It is also possible to use mixtures of trialkylaluminum's with alkylaluminum halides, alkylaluminum hydrides or alkylaluminum sesquichlorides such as AlEt2Cl and Al2Et3Cl3. It has been found particularly advantageous to carry out said prepolymerization using low amounts of alkyl-Al compound. In particular said amount can be such as to have an Al/Ti molar ratio from 0.0001 to 50, preferably from 0.001 to 10 and more preferably from 0.01 to 1. Moreover, it has also been found advantageous to carry out said prepolymerization in the absence of an external donor compound. The prepolymerization can be carried out in liquid phase, (slurry or solution) or in gas- phase at temperatures generally lower than 80°C, preferably between -20 and 50°C. Furthermore, it is preferably carried out in a liquid diluent in particular selected from liquid hydrocarbons. Among them, pentane, hexane and heptane are preferred. As explained the so obtained prepolymerized catalyst components can be used in the polymerization of olelin.s, and in particular of propylene, allowing to obtain high activity and polymers with high stereoregularity, high bulk density and very good morphology thus showing their particular suitability for the liquid (bulk or slurry) and gas-phase processes. In addition, as it is shown in the examples, aging problems are solved since the activity of the catalyst remains unaltered or even improved in some cases, after several months of time. Accordingly, the catalyst components of the invention are particularly suitable for the use in liquid or gas-phase olefin polymerization plants operating without a prepolymerization line. In particular, said olefin polymerization processes can be carried out in the presence of a catalyst comprising (A) the prepolymerized catalyst component; (B) an Al-alkyl compound of the type described above and optionally (C) one or more electron donor (external) compound. This latter can be of the same type or it can be different from the internal donor described above. Suitable external electron donor compounds include silicon compounds, ethers, esters, amines, heterocyclic compounds and particularly 2,2,6,6-tetramethyl piperidine, ketones and the 1,3-diethers of the general formula (I) given above. Another class of preferred external donor compounds is that of silicon compounds of formula Ra5Rb6Si(OR7)c, 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; R5, R6, and R7, are alkyl, cycloalkyl or aryl radicals with 1-18 carbon atoms optionally containing heteroatoms. Particularly preferred are the silicon compounds in which a is 1, b is 1, c is 2, at least one of R5 and R6 is selected from branched alkyl, cycloalkyl or aryl groups with 3-10 carbon atoms optionally containing heteroatoms and R7 is a C1-C10 alkyl group, in particular methyl. Examples of such preferred silicon compounds are methylcyclohexyldimethoxysilane, diphenyldimethoxysilane, methyl-t-butyldimethoxysilane, dicyclopentyldimethoxysilane, 2-ethylpiperidinyl-2-t-butyldimethoxysilane and 1,1,1 .lrifluoropropyl 2-ethylpiperidinyl-dimethoxysilane, Moreover, are also preferred the silicon compounds in which a is 0, c is 3, R6 is a branched alkyl or cycloalkyl group, optionally containing heteroatoms, and R7 is methyl. Examples of such preferred silicon compounds are cyclohexyltrimethoxysilane, t-butyltrimethoxysilane and thexyltrimethoxysilane. In particular when esters of monocarboxylic acids, for example benzoates are used as internal donors also the external donor compound is selected from this class p-ethoxy-ethyl benzoate being the most preferred. In addition, a mixture of this donor with another one and in particular one selected from the class of silicon compounds can be used. In this case methylcyclohexyldimethoxysilane and dicyclopentyldimethoxysilane are most preferred. The electron donor compound (C) is used in such an amount to give a molar ratio between the organoaluminum compound and said electron donor compound of from 0.1 to 500, preferably from 1 to 300 and more preferably from 3 to 100. The above described polymerization process can be carried out under the polymerization conditions generally known in the art. Accordingly, 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 0.5 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. In any of the polymerization processes used (liquid or gas-phase polymerization) the catalyst forming components (A), (B) and optionally (C), can be pre-contacted before adding them to the polymerization reactor. Said pre-contacting step can be carried out in the absence of polymerizable olefin or optionally in the presence of said olefin in an amount up to 3 g per g of solid catalyst component. The catalyst forming components can be contacted with a liquid inert hydrocarbon solvent such as propane, n-hexane, or n-heptane at a temperature below about 60°C and preferably from about 0°C to 30°C for a time period of from 10 seconds to 60 minutes. When n gas-phase polymerization process is used, it can be carried out according to known techniques operating in ore or more reactors having a fluidized or mechanically agitated bed. Inert fluids such as nitrogen, or low hydrocarbons like propane, can be used both as a fluidization aid and in order to improve the thermal exchange within the reactors. In addition, also techniques increasing the removal of the reaction heat comprising the introduction of liquids, optionally in mixture with gas, into the reactors, can be used. Preferably the liquids are fresh or make-up monomers. Such techniques are disclosed for example in EP-A-89691, EP-A-241947, USP 5,352,749, WO94/28032 and EPA-695313. The following examples are given in order better illustrate the invention without limiting it. EXAMPLES Characterization Determination of X.I. 2.5 g of polymer were dissolved in 250 ml of o-xylene under stirring at 135EC for 30 minutes, then the solution was cooled to 25°C and after 30 minutes the insoluble polymer was filtered. The resulting solution was evaporated in nitrogen flow and the residue was dried and weighed to determine the percentage of soluble polymer and then, by difference, the X.I. %. General procedure for the standard propylene polymerization test A 4-liter steel autoclave equipped with a stirrer, pressure gauge, thermometer, catalyst- feeding system, monomer feeding lines and thermostatting jacket, was used. The reactor was charged with 0.01 g of solid catalyst component and with TEAL, and cyclohexyl-methyl dimethoxy silane in such amounts to give an Al/Donor molar ratio of 20. Moreover, 3.2 1 of propylene, and 1.5 1 of hydrogen were added. The system was heated to 70°C over 10 min. under stirring, and maintained under these conditions for 120 min. At the end of the polymerization, the polymer was recovered by removing any umeacted monomers and was dried under vacuum. Determination of Melt Index ASTM D 1238 condition "L" Examples 1-2 and comparison example 3 Preparation of Solid Catalyst Component Into a 500 ml four-necked round flask, purged with nitrogen, 250 ml of TiC14 were introduced at 0°C. While stirring, 10 g of microspheroidal MgCl2.C2H5OH containing about 54%weight of alcohol were added. The flask was heated to 40°C and 6 mmoles of diisobutylphthalate were thereupon added. The temperature was raised to 100°C and maintained for two hours, then the stirring was discontinued, the solid product was allowed to settle and the supernatant liquid was siphoned off. The treatment with TiCl4 was repeated and the solid obtained was washed six times with anhydrous hexane (6 x 100 ml) at 60°C and then dried under vacuum: The characteristics of the catalyst components and the results of the propylene polymerization test procedure are reported in table 1. Ethylene Prepolymerization The catalyst components prepared according to the above procedure were prepolymerized with ethylene under the conditions reported in table 2. In comparison example 4 prepolymerization was not carried out. Propylene Polymerization The prepolymerized catalyst obtained was then used in the polymerization of propylene carried out in a bulk pilot polymerization plant under the following conditions: Al/Cat (weight ratio): 8 Al/Donor (weight ratio): 6 Donor/cat (weight ratio): 1.3 Time (min.): 80 Temperature (°C): 70 The results are shown in table 3. Example 4-5 and comparison example 6 Preparation of the catalyst component The catalyst components were prepared according to the procedure of example 1 but using ethyl benzoate instead of diisobutylphthalate. The characteristics of the catalyst components and the results of the propylene polymerization test procedure are reported in table 1. Ethylene Prepolymerization The catalyst components prepared according to the above procedure were prepolymerized with ethylene under the conditions reported in table 2. In comparison example 6 prepolymerization was not carried out. Propylene Polymerization The catalyst components obtained were then used in the polymerization of propylene which was carried out in a bulk pilot polymerization plant under the following conditions: Al/Cat (weight ratio): 4.6 Al/Donor (weight ratio): 1.4 Donor/cat (weight ratio): 3.2 Time (min.): 80 Temperature (°C): 70 using p-ethoxy-ethylbenzoate as external donor The results are shown in table 3. Example 7 and comparison example 8 The catalyst components were prepared according to the procedure of example 4 but using 9,9-bis(methoxymethyl)-fluorene instead of ethyl benzoate. The characteristics of the catalyst components and the results of the propylene polymerization test procedure are reported in table 1. Ethylene Prepilymerization The catalyst components prepared according to the above procedure were prepolymerized with ethylene under the conditions reported in table 2. In comparison example 8 prepolymerization was not carried out. Propylene Polymerization The catalyst components obtained were then used in the polymerization of propylene which was carried out in a bulk pilot polymerization plant under the following conditions: Al/Cat (weight ratio): 13.7 Time (min.): 80 Temperature (°C): 70 without using an external donor The results are shown in table 3. Evaluation of aging properties The catalyst components prepared according to the examples 4 and 5 were tested for the polymerization of propylene in order to evaluate their aging properties. A first test was carried out after the prepolymerization and a further test was carried out after 120 days. All the tests were carried out according to the general standard procedure but using p-ethoxy- ethylbenzoate as external donor in an amount such as to give an Al/donor molar ratio of 1.8. The results are reported in table 4. TABLE 3 Polymerization results with the prepolymerized catalyst components We claim: 1. A prepolymerized catalyst component for the polymerization of olefins CH2=CHR, wherein R is hydrogen or a C1-C12 alkyl group, characterized by comprising a solid catalyst component comprising Mg, Ti, halogen and an electron donor compound and being capable of yielding under standard propylene polymerization conditions a propylene homopolymer having an insolubility in xylene at 25°C higher than 90%, said solid catalyst component being prepolymerized with ethylene to such an extent that the amount of the ethylene prepolymer is up to 100g per g of solid catalyst component. 2. Catalyst component as claimed in claim 1 in which the amount of ethylene polymer is less than 15 g per g of solid catalyst component. 3. Catalyst component as claimed in claim 2 in which the amount of ethylene is less than 5 g per g of solid catalyst component. 4. Catalyst component as claimed in claim 1 in which the solid catalyst component comprises a titanium compound having at least a Ti-halogen bond and an electron donor compound supported on a Mg halide in active form. 5. Prepolymerized catalyst component as claimed in any of the preceding claims wherein the solid catalyst component is obtained by reacting a titanium compound of formula Ti(OR)n-yXy, where n is the valence of titanium and y is a number between 1 and n, with an adduct of formula MgCI2.pROH, where p is a number between 0,1 and 6 and R is a hydrocarbon radical having 1-18 carbon atoms. 6. Catalyst component as claimed in any of claims 5 in which the titanium compound is TiCI4. 7. Catalyst component as claimed in claim 1 in which the internal electron-donor compound is selected from esters, ethers, amines and ketones. 8. Catalyst component as claimed in claim 6 in which said internal electron donor is selected from alkyl, cycloalkyl or aryl esters of monocarboxylic acids, the said alkyl, cycloalkyl or aryl groups having from 1 to 18 carbon atoms. 9. Catalyst component as claimed in claim 6 in which the internal electron donor is selected from the group consisting of ethyl benzoate and disobutyl phthalate. 10. Catalyst component as claimed in claim 1 in which the internal electron donor is selected form 1,3, dithers of formula (I): Wherein RI, RII, RIII, RIV, Rv and RVI equal or different to each other, are hydrogen or hydrocarbon radicals having from 1 to 18 carbon atoms, and RVII and RVIII, equal or different from each other, have the same meaning of RI-RVI except that they cannot be hydrogen; one or more of the RI-RVIII groups can be linked to form a cycle. 11. Catalyst component as claimed in claim 10 in which RVII and RVIII are selected from C1-C4 alkyl radicals and the groups RIII and RIV are linked to form a cycle. 12. Catalyst for the polymerization of olefins CH2=CHR, wherein R is hydrogen or a hydrocarbon radical having 1-12 carbon atoms comprising a prepolymerized catalyst component as claimed in any of the claims 1-11, an aluminum alkyl compound and, optionally, one or more electron donor compounds. 13. Catalyst as claimed in claim 12 in which a benzoate is used both as internal and external electron donor. 14. Catalyst as claimed in claim 13 in which a mixture of a benzoate and a silicon compounds are used as external electron donors. 15. Catalyst as claimed in claim 13 in which ethyl benzoate is the internal electron donor, and ethoxy ethylbenzoate is the external electron donor. 16. Catalyst as claimed in claim 14 in which ethyl benzoate is the internal electron donor and the external electron donor comprises a mixture p-ethoxy ethylbenzoate and dicyclopentyldimethoxysilane. The invention provides new prepolymerized catalyst components for the (co) polymerization of olefins CH2=CHR, wherein R is hydrogen or a C1-C12 alkyl group, characterized by comprising a solid catalyst component, comprising Ti, Mg, halogen and an electron donor compound, being capable of yielding, under standard polymerization conditions, a propyiene homopolymers having an insolubility in xylene at 25C higher than 90%, which is prepolymerized with ethylene to such an extent that the amount of the ethylene prepolymer is up to 100g per g of said solid catalyst component. These such catalyst components allow to obtain a high catalyst activity, a high isotactic index and are not affected by aging.

Full Text

"PREPOLYMERIZED CATALYST COMPONENTS FOR THE POLYMERIZATION
OF OLEFINS"
The present invention relates to catalyst components for the polymerization of olefins
CH2 = CHR, wherein R is hydrogen or a hydrocarbon radical having 1-12 carbon atoms,
the catalysts obtained therefrom and their use in the polymerization of said olefins.
In particular the catalyst components of the present invention are very suitable for the
preparation of crystalline propylene (co)polymers by using gas-phase, slurry or bulk
(co)polymerization processes.
High-yield catalyst components for the polymerization of olefins and in particular for
propylene are known in the art. They are generally obtained by supporting, on a
magnesium dihalide, a titanium compound and an electron donor compound as a selectivity
control agent. Said catalyst components are then used together with an aluminum alkyl and,
optionally, another electron donor (external) compound in the stereospecific polymerization
of propylene. Depending on the type of electron donor used the stereoregularity of the
polymer can vary. However, the stereospecific catalysts of interest should be able to give
polypropylene (co)polymers having isotactic index, expressed in terms of xylene
insolubility, of higher than 90%.
Said catalyst components, and the catalysts obtained therefrom, are largely used in the
plants for the (co)polymerization of propylene both operating in liquid phase (slurry or
bulk) and in gas-phase. However, the use of the catalyst components as such is not
completely satisfactory. Indeed, problems such as formation of polymers with irregular
morphology and in particular of fines, low bulk density and low catalyst activity are
experienced when plants operate with catalyst components as such.
In order to solve these problems, an additional prepolymerization line may be included, in
which the catalyst is prepolymerized under controlled conditions, so as to obtain
prepolymerized catalysts having good morphology. After prepolymerization, the catalysts
also increase their resistance in such a way that the tendency to break under polymerization
conditions is decreased. As a consequence, also the formation of fines is reduced.
Moreover also the activity of the catalyst and the bulk density of the final polymers results
to be improved. The use of this additional line, however, makes the plant operations and
design more complex and costly; in certain cases it is therefore desirable to avoid it.
One of the alternative solutions is that of supplying the plants directly with a
prepolymerized catalyst which can be prepared in another facility. This solution requires
the preparation of a prepolymerized catalyst meeting certain requirements such as easy
preparation and handling, easy stocking operability, absence or minimal reduction of
activity with time (aging) preferably coupled with a basic high activity.
USP 5,641,721 discloses a method for preparing a prepolymerized catalyst comprising (i)
the preparation of a procatalyst composition by depositing a transition metal compound on a
suitable support, (ii) mixing said procatalyst composition with a viscous substance and then
prepolymerizing said procatalyst composition with a monomer in the presence of said
viscous substance. The viscous substance has a viscosity of from 1000 to 15000 cP while
the monomer used is propylene. Albeit it is alleged that the catalyst activity is unchanged
after 5 months, it appears that the selectivity is decreased. Moreover, the prepolymerization
in such a viscous substance makes the preparation of the prepolymerized catalyst complex
and, in addition, leads to a low catalyst activity.
It has now surprisingly been found that by carrying out the prepolymerization with a
specific monomer it is possible to obtain a catalyst for the polymerization of olefins which
has a high catalyst activity, a high isotactic index and which is not affected by aging.
It is therefore an object of the present invention a prepolymerized catalyst component for
the (co)polymerization of olefins CH2 = CHR. wherein R is hydrogen or a C1-C12 alkyl
group, characterized by comprising a solid catalyst component, comprising Ti, Mg,
halogen and an electron donor compound, being capable of yielding, under standard
polymerization conditions, a propylene homopolymer having an insolubility in xylene at
25°C higher than 90%, which is prepolymerized with ethylene to such an extent that the
amount of the ethylene prepolymer is up to 100g per g of said solid catalyst component.
Preferably the amount of ethylene polymer is less than 15 g and more preferably said
amount is less than 5 g per g of solid catalyst component.
In particular, the catalyst components comprise a titanium compound, having at least a Ti-
halogen bond and the above mentioned electron donor compound supported on a Mg halide.
The magnesium halides, preferably MgCl2, in active form used as a support for Ziegler-
Natta catalysts, are widely known from the patent literature. Patents USP 4,298,718 and
USP 4,495,338 were the first to describe the use of these compounds in 7,iegler-Natta
catalysis. It is known from these patents that the magnesium dihalides in active form used
as support or co-support in components of catalysts for the polymerization of olefins are
characterized by X-ray spectra in which the most intense diffraction line that appears in the
spectrum of the non-active halide is diminished in intensity and is replaced by a halo whose
maximum intensity is displaced towards lower angles relative to that of the more intense
line.
The preferred titanium compounds used in the catalyst component of the present invention
are TiCl4 and TiCl3; furthermore, also Ti-haloalcoholates of formula Ti(OR)n-yXy, where n
is the valence of titanium and y is a number between 1 and n, can be used.
The internal electron-donor compound may be selected from esters, ethers, amines and
ketones. It is preferably selected from alkyl, cycloalkyl or aryl esters of monocarboxylic
acids, for example benzoic acid, or polycarboxylic acids, for example phthalic or malonic
acid, the said alkyl, cycloalkyl or aryl groups having from 1 to 18 carbon atoms.
Moreover, it can be also selected from 1,3-diethers of formula (I):

wherein RI, RII, RIII, RIV, RV and RVI equal or different to each other, are hydrogen or
hydrocarbon radicals having from 1 to 18 carbon atoms, and RVII and RVIII, equal or
different from each other, have the same meaning of RI-RVI except that they cannot be
hydrogen; one or more of the RI-RVIII groups can be linked to form a cycle. Particularly
preferred are the 1,3-diethers in which RVII and RVIII are selected from C1-C4 alkyl radicals.
Examples of preferred electron-donor compounds are methyl benzoate, ethyl benzoate,
diisobutyl phthalate and 9,9-bis(methoxymethyl)fluorene. As explained above, however,
the internal electron donor compound must be selected in such a way to have a final solid
catalyst component capable of producing, under the standard polymerization test disclosed
below, a propylene homopolymer having an insolubility in xylene at 25°C higher than
90%.
The preparation of the solid catalyst component can be carried out according to several
methods. According to one of these methods, the magnesium dichloride in an anhydrous
state, the titanium compound and the electron donor compound of formula (I) are milled
together under conditions in which activation of the magnesium dichloride occurs. The so
obtained product can be treated one or more times with an excess of TiCl4 at a temperature
between 80 and 135°C. This treatment is followed by washings with hydrocarbon solvents
until chloride ions disappeared. According to a further method, the product obtained by co-
milling the magnesium chloride in an anhydrous state, the titanium compound and the
electron donor compound is treated with halogenated hydrocarbons such as 1,2-
dichloroethane, chlorobenzene, dichloromethane etc. The treatment is carried out for a time
between 1 and 4 hours and at temperature of from 40°C to the boiling point of the
halogenated hydrocarbon. The product obtained is then generally washed with inert
hydrocarbon solvents such as hexane.
According to another method, magnesium dichloride is preactivated according to well
known methods and then treated with an excess of TiCl4 at a temperature of about 80 to
135°C in the presence of the electron donor compound. The treatment with TiCl4 is
repeated and the solid is washed with hexane in order to eliminate any non-reacted TiCl4.
A further method comprises the reaction between magnesium alcoholates or
chloroalcoholates (in particular chloroalcoholates prepared according to U.S. 4,220,554)
and an excess of TiCl4 in the presence of an electron donor compound (I) at a temperature
of about 80 to 120°C.
Particularly preferred are the solid catalyst component prepared by reacting a titanium
compound of formula Ti(OR)n-yXy, where n is the valence of titanium and y is a number
between 1 and n, preferably TiCl4, with an adduct of formula MgCl2.pROH, where p is a
number between 0,1 and 6 and R is a hydrocarbon radical having 1-18 carbon atoms. The
adduct can be suitably prepared in spherical form by mixing alcohol and magnesium
chloride in the presence of an inert hydrocarbon immiscible with the adduct, operating
under stirring conditions at the melting temperature of the adduct (100-130°C). Then, the
emulsion is quickly quenched, thereby causing the solidification of the adduct in form of
spherical particles. Examples of spherical adducts prepared according to this procedure are
described in USP 4,399,054. The so obtained adduct can be directly reacted with the Ti
compound or it can be previously subjected to thermal controlled dealcoholation (80-
130°C) so as to obtain an adduct in which the number of moles of alcohol is generally
lower than 3 preferably between 0.1 and 2.5. The dealcoholated adduct is then suspended
in cold TiCl4 (generally 0°C); the mixture is heated up to 80-130°C and kept at this
temperature for 0.5-2 hours. The treatment with TiCl4 can be carried out one or more
times. The internal electron donor compound can be added during the treatment with TiCl4.
The treatment with the electron donor compound can be repeated one or more times.
The preparation of catalyst components in spherical form is described for example in
European Patent Applications EP-A-395083.
The solid catalyst components obtained according to the above method show a surface area
(by B.E.T. method) generally between 20 and 500 nr/g and preferably between 50 and 400
nr/g, and more preferably between 100 and 400 nr/g; a total porosity (by B.E.T. method)
higher than 0.2 cm3/g preferably between 0.2. and 0.6 cm3/g and more preferably from 0.3
to 0.5 cm3/g. The porosity (Hg method) due to pores with radius up to 10.000A generally
ranges from 0.3 to 1.5 cm3/g. preferably from 0.45 to 1 cm3/g.
A further method to prepare the solid catalyst component of the invention comprises
halogenating magnesium dihydrocarbyloxide compounds, such as magnesium dialkoxide or
diaryloxide, with solution of TiCl, in aromatic hydrocarbon (such as toluene, xylene etc.)
at temperatures between 80 and 130°C. The treatment with TiCl4 in aromatic hydrocarbon
solution can be repeated one or more times, and the internal electron donor compound is
added during one or more of these treatments. In any of these preparation methods, the
desired internal electron donor compound can be added as such or, in an alternative way, it
can be obtained in situ by using an appropriate precursor capable to be transformed in the
desired electron donor compound by means, for example, of known chemical reactions
such as esterification, transesterificution etc. Generally, the internal electron donor
compound is used in molar ratio with respect to the MgCl2, of from 0.01 to 1 preferably
from 0.05 to 0.5.
As explained above the prepolymerized catalyst component can be obtained by
prepolymerizing the solid catalyst component together with ethylene. The
prepolymerization is normally carried out in the presence of an Al-alkyl compound.
The alkyl-Al compound (B) is preferably chosen among the trialkyl aluminum compounds
such as for example triethylaluminum, triisobutylaluminum, tri-n-butylaluminum, tri-n-
hexylaluminum, tri-n-octylaluminum. It is also possible to use mixtures of
trialkylaluminum's with alkylaluminum halides, alkylaluminum hydrides or alkylaluminum
sesquichlorides such as AlEt2Cl and Al2Et3Cl3.
It has been found particularly advantageous to carry out said prepolymerization using low
amounts of alkyl-Al compound. In particular said amount can be such as to have an Al/Ti
molar ratio from 0.0001 to 50, preferably from 0.001 to 10 and more preferably from 0.01
to 1.
Moreover, it has also been found advantageous to carry out said prepolymerization in the
absence of an external donor compound.
The prepolymerization can be carried out in liquid phase, (slurry or solution) or in gas-
phase at temperatures generally lower than 80°C, preferably between -20 and 50°C.
Furthermore, it is preferably carried out in a liquid diluent in particular selected from
liquid hydrocarbons. Among them, pentane, hexane and heptane are preferred.
As explained the so obtained prepolymerized catalyst components can be used in the
polymerization of olelin.s, and in particular of propylene, allowing to obtain high activity
and polymers with high stereoregularity, high bulk density and very good morphology thus
showing their particular suitability for the liquid (bulk or slurry) and gas-phase processes.
In addition, as it is shown in the examples, aging problems are solved since the activity of
the catalyst remains unaltered or even improved in some cases, after several months of
time. Accordingly, the catalyst components of the invention are particularly suitable for the
use in liquid or gas-phase olefin polymerization plants operating without a
prepolymerization line.
In particular, said olefin polymerization processes can be carried out in the presence of a
catalyst comprising (A) the prepolymerized catalyst component; (B) an Al-alkyl compound
of the type described above and optionally (C) one or more electron donor (external)
compound.
This latter can be of the same type or it can be different from the internal donor described
above. Suitable external electron donor compounds include silicon compounds, ethers,
esters, amines, heterocyclic compounds and particularly 2,2,6,6-tetramethyl piperidine,
ketones and the 1,3-diethers of the general formula (I) given above.
Another class of preferred external donor compounds is that of silicon compounds of formula
Ra5Rb6Si(OR7)c, 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; R5, R6, and R7, are alkyl, cycloalkyl or aryl radicals with 1-18 carbon atoms
optionally containing heteroatoms. Particularly preferred are the silicon compounds in which a
is 1, b is 1, c is 2, at least one of R5 and R6 is selected from branched alkyl, cycloalkyl or aryl
groups with 3-10 carbon atoms optionally containing heteroatoms and R7 is a C1-C10 alkyl
group, in particular methyl. Examples of such preferred silicon compounds are
methylcyclohexyldimethoxysilane, diphenyldimethoxysilane, methyl-t-butyldimethoxysilane,
dicyclopentyldimethoxysilane, 2-ethylpiperidinyl-2-t-butyldimethoxysilane and
1,1,1 .lrifluoropropyl 2-ethylpiperidinyl-dimethoxysilane, Moreover, are also preferred the
silicon compounds in which a is 0, c is 3, R6 is a branched alkyl or cycloalkyl group, optionally
containing heteroatoms, and R7 is methyl. Examples of such preferred silicon compounds are
cyclohexyltrimethoxysilane, t-butyltrimethoxysilane and thexyltrimethoxysilane.
In particular when esters of monocarboxylic acids, for example benzoates are used as
internal donors also the external donor compound is selected from this class p-ethoxy-ethyl
benzoate being the most preferred. In addition, a mixture of this donor with another one
and in particular one selected from the class of silicon compounds can be used. In this case
methylcyclohexyldimethoxysilane and dicyclopentyldimethoxysilane are most preferred.
The electron donor compound (C) is used in such an amount to give a molar ratio between the
organoaluminum compound and said electron donor compound of from 0.1 to 500, preferably
from 1 to 300 and more preferably from 3 to 100.
The above described polymerization process can be carried out under the polymerization
conditions generally known in the art. Accordingly, 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 0.5 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.
In any of the polymerization processes used (liquid or gas-phase polymerization) the catalyst
forming components (A), (B) and optionally (C), can be pre-contacted before adding them to
the polymerization reactor. Said pre-contacting step can be carried out in the absence of
polymerizable olefin or optionally in the presence of said olefin in an amount up to 3 g per g
of solid catalyst component. The catalyst forming components can be contacted with a liquid
inert hydrocarbon solvent such as propane, n-hexane, or n-heptane at a temperature below
about 60°C and preferably from about 0°C to 30°C for a time period of from 10 seconds to
60 minutes.
When n gas-phase polymerization process is used, it can be carried out according to known
techniques operating in ore or more reactors having a fluidized or mechanically agitated bed.
Inert fluids such as nitrogen, or low hydrocarbons like propane, can be used both as a
fluidization aid and in order to improve the thermal exchange within the reactors. In addition,
also techniques increasing the removal of the reaction heat comprising the introduction of
liquids, optionally in mixture with gas, into the reactors, can be used. Preferably the liquids
are fresh or make-up monomers. Such techniques are disclosed for example in EP-A-89691,
EP-A-241947, USP 5,352,749, WO94/28032 and EPA-695313.
The following examples are given in order better illustrate the invention without limiting it.
EXAMPLES
Characterization
Determination of X.I.
2.5 g of polymer were dissolved in 250 ml of o-xylene under stirring at 135EC for 30
minutes, then the solution was cooled to 25°C and after 30 minutes the insoluble polymer was
filtered. The resulting solution was evaporated in nitrogen flow and the residue was dried and
weighed to determine the percentage of soluble polymer and then, by difference, the X.I. %.
General procedure for the standard propylene polymerization test
A 4-liter steel autoclave equipped with a stirrer, pressure gauge, thermometer, catalyst-
feeding system, monomer feeding lines and thermostatting jacket, was used. The reactor was
charged with 0.01 g of solid catalyst component and with TEAL, and cyclohexyl-methyl
dimethoxy silane in such amounts to give an Al/Donor molar ratio of 20. Moreover, 3.2 1 of
propylene, and 1.5 1 of hydrogen were added. The system was heated to 70°C over 10 min.
under stirring, and maintained under these conditions for 120 min. At the end of the
polymerization, the polymer was recovered by removing any umeacted monomers and was
dried under vacuum.
Determination of Melt Index
ASTM D 1238 condition "L"
Examples 1-2 and comparison example 3
Preparation of Solid Catalyst Component
Into a 500 ml four-necked round flask, purged with nitrogen, 250 ml of TiC14 were
introduced at 0°C. While stirring, 10 g of microspheroidal MgCl2.C2H5OH containing
about 54%weight of alcohol were added. The flask was heated to 40°C and 6 mmoles of
diisobutylphthalate were thereupon added. The temperature was raised to 100°C and
maintained for two hours, then the stirring was discontinued, the solid product was allowed
to settle and the supernatant liquid was siphoned off.
The treatment with TiCl4 was repeated and the solid obtained was washed six times with
anhydrous hexane (6 x 100 ml) at 60°C and then dried under vacuum: The characteristics
of the catalyst components and the results of the propylene polymerization test procedure
are reported in table 1.
Ethylene Prepolymerization
The catalyst components prepared according to the above procedure were prepolymerized
with ethylene under the conditions reported in table 2. In comparison example 4
prepolymerization was not carried out.
Propylene Polymerization
The prepolymerized catalyst obtained was then used in the polymerization of propylene
carried out in a bulk pilot polymerization plant under the following conditions:
Al/Cat (weight ratio): 8
Al/Donor (weight ratio): 6
Donor/cat (weight ratio): 1.3
Time (min.): 80
Temperature (°C): 70
The results are shown in table 3.
Example 4-5 and comparison example 6
Preparation of the catalyst component
The catalyst components were prepared according to the procedure of example 1 but using
ethyl benzoate instead of diisobutylphthalate. The characteristics of the catalyst components
and the results of the propylene polymerization test procedure are reported in table 1.
Ethylene Prepolymerization
The catalyst components prepared according to the above procedure were prepolymerized
with ethylene under the conditions reported in table 2. In comparison example 6
prepolymerization was not carried out.
Propylene Polymerization
The catalyst components obtained were then used in the polymerization of propylene which
was carried out in a bulk pilot polymerization plant under the following conditions:
Al/Cat (weight ratio): 4.6
Al/Donor (weight ratio): 1.4
Donor/cat (weight ratio): 3.2
Time (min.): 80
Temperature (°C): 70
using p-ethoxy-ethylbenzoate as external donor The results are shown in table 3.
Example 7 and comparison example 8
The catalyst components were prepared according to the procedure of example 4 but using
9,9-bis(methoxymethyl)-fluorene instead of ethyl benzoate. The characteristics of the
catalyst components and the results of the propylene polymerization test procedure are
reported in table 1.
Ethylene Prepilymerization
The catalyst components prepared according to the above procedure were prepolymerized
with ethylene under the conditions reported in table 2. In comparison example 8
prepolymerization was not carried out.
Propylene Polymerization
The catalyst components obtained were then used in the polymerization of propylene which
was carried out in a bulk pilot polymerization plant under the following conditions:
Al/Cat (weight ratio): 13.7
Time (min.): 80
Temperature (°C): 70
without using an external donor The results are shown in table 3.
Evaluation of aging properties
The catalyst components prepared according to the examples 4 and 5 were tested for the
polymerization of propylene in order to evaluate their aging properties. A first test was
carried out after the prepolymerization and a further test was carried out after 120 days. All
the tests were carried out according to the general standard procedure but using p-ethoxy-
ethylbenzoate as external donor in an amount such as to give an Al/donor molar ratio of
1.8. The results are reported in table 4.
TABLE 3
Polymerization results with the prepolymerized catalyst components
We claim:
1. A prepolymerized catalyst component for the polymerization of olefins
CH2=CHR, wherein R is hydrogen or a C1-C12 alkyl group, characterized by
comprising a solid catalyst component comprising Mg, Ti, halogen and an
electron donor compound and being capable of yielding under standard
propylene polymerization conditions a propylene homopolymer having an
insolubility in xylene at 25°C higher than 90%, said solid catalyst component
being prepolymerized with ethylene to such an extent that the amount of the
ethylene prepolymer is up to 100g per g of solid catalyst component.
2. Catalyst component as claimed in claim 1 in which the amount of ethylene
polymer is less than 15 g per g of solid catalyst component.
3. Catalyst component as claimed in claim 2 in which the amount of ethylene is
less than 5 g per g of solid catalyst component.
4. Catalyst component as claimed in claim 1 in which the solid catalyst
component comprises a titanium compound having at least a Ti-halogen bond
and an electron donor compound supported on a Mg halide in active form.
5. Prepolymerized catalyst component as claimed in any of the preceding claims
wherein the solid catalyst component is obtained by reacting a titanium
compound of formula Ti(OR)n-yXy, where n is the valence of titanium and y is
a number between 1 and n, with an adduct of formula MgCI2.pROH, where p
is a number between 0,1 and 6 and R is a hydrocarbon radical having 1-18
carbon atoms.
6. Catalyst component as claimed in any of claims 5 in which the titanium
compound is TiCI4.
7. Catalyst component as claimed in claim 1 in which the internal electron-donor
compound is selected from esters, ethers, amines and ketones.
8. Catalyst component as claimed in claim 6 in which said internal electron
donor is selected from alkyl, cycloalkyl or aryl esters of monocarboxylic acids,
the said alkyl, cycloalkyl or aryl groups having from 1 to 18 carbon atoms.
9. Catalyst component as claimed in claim 6 in which the internal electron donor
is selected from the group consisting of ethyl benzoate and disobutyl
phthalate.
10. Catalyst component as claimed in claim 1 in which the internal electron donor
is selected form 1,3, dithers of formula (I):

Wherein RI, RII, RIII, RIV, Rv and RVI equal or different to each other, are
hydrogen or hydrocarbon radicals having from 1 to 18 carbon atoms, and RVII
and RVIII, equal or different from each other, have the same meaning of RI-RVI
except that they cannot be hydrogen; one or more of the RI-RVIII groups can
be linked to form a cycle.
11. Catalyst component as claimed in claim 10 in which RVII and RVIII are selected
from C1-C4 alkyl radicals and the groups RIII and RIV are linked to form a
cycle.
12. Catalyst for the polymerization of olefins CH2=CHR, wherein R is hydrogen or
a hydrocarbon radical having 1-12 carbon atoms comprising a prepolymerized
catalyst component as claimed in any of the claims 1-11, an aluminum alkyl
compound and, optionally, one or more electron donor compounds.
13. Catalyst as claimed in claim 12 in which a benzoate is used both as internal
and external electron donor.
14. Catalyst as claimed in claim 13 in which a mixture of a benzoate and a silicon
compounds are used as external electron donors.
15. Catalyst as claimed in claim 13 in which ethyl benzoate is the internal electron
donor, and ethoxy ethylbenzoate is the external electron donor.
16. Catalyst as claimed in claim 14 in which ethyl benzoate is the internal electron
donor and the external electron donor comprises a mixture p-ethoxy
ethylbenzoate and dicyclopentyldimethoxysilane.
The invention provides new prepolymerized catalyst components for the (co)
polymerization of olefins CH2=CHR, wherein R is hydrogen or a C1-C12 alkyl
group, characterized by comprising a solid catalyst component, comprising Ti,
Mg, halogen and an electron donor compound, being capable of yielding, under
standard polymerization conditions, a propyiene homopolymers having an
insolubility in xylene at 25C higher than 90%, which is prepolymerized with
ethylene to such an extent that the amount of the ethylene prepolymer is up to
100g per g of said solid catalyst component. These such catalyst components
allow to obtain a high catalyst activity, a high isotactic index and are not affected
by aging.

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Patent Number

225410

Indian Patent Application Number

00906/KOLNP/2005

PG Journal Number

46/2008

Publication Date

14-Nov-2008

Grant Date

12-Nov-2008

Date of Filing

17-May-2005

Name of Patentee

BASELL TECHNOLOGY COMPANY B. V

Applicant Address

HOEKSTEEN 66, NL-2132 MS HOOFDDROP

Inventors:

#	Inventor's Name	Inventor's Address
1	GOVONI, GABRIELE	VIA PILASTRO, 63, 1-44045 RENAZZO
2	SACCHETTI, MARIO	VIALE KRASNODAR, 138, I-44100 FERRARA
3	VITALE, GIANNI	VIA FULVIO TESTI, 22, I-44100 FERRARA

PCT International Classification Number

C08F 4/654, 4/647

PCT International Application Number

PCT/EP99/01804

PCT International Filing date

1999-03-18

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	98200907.8	1998-03-23	EUROPEAN UNION