Homo - or copolymers of ethylene and methods for their production

 

(57) Abstract:

The invention relates to new Homo - and copolymers of ethylene having a degree of swelling at least 1,4, resistance to cracking under load at least 55 h and the flow index of at least 0.2 g/10 minutes Describes how they are received. The invention relates to Homo - and copolymers of ethylene having a preferred combination of properties that make them especially suitable for processing by extrusion and extrusion blow for the manufacture of products (e.g., pipes), with excellent mechanical properties and high resistance to cracking under stress. 4 C. and 9 C.p. f-crystals.

The invention relates to Homo - and copolymers of ethylene having a preferred combination of properties that make them especially suitable for processing by extrusion and extrusion blow for the manufacture of products (e.g., pipes), with excellent mechanical properties and high resistance to cracking under stress. The invention also relates to various methods of producing these polymers of ethylene.

It is well known that resins having wask the processing extrusion and blown. For example, in Belgium patent BE 840 378 (Solvay andabout) describes the polyethylene obtained by polymerization in a single reactor in the presence of a solid catalyst, which is obtained by interaction of the oxygen-containing magyarkanizsa compounds with oxygen-containing technologicheski compound and oxygen-containing zirconium-organic compound, and then by processing the obtained reaction product by using a halide of aluminum. Known for polyethylene plastics have a high degree of swelling. However, their mechanical properties such that the resistance of pipes to cracking under load, obtained by extrusion of these polyethylenes, a minor.

In addition, the known polyethylene with improved mechanical properties and particularly high resistance to cracking under stress. For example, in European patent application EP 603 935 (Solvay) disclosed ethylene polymers obtained by polymerization in at least two reactors installed in series in the presence of a catalyst based on titanium. The obtained ethylene polymers have good mechanical properties (high resistance to cracking under load). the is the elimination of the aforementioned disadvantages of using the new (co)polymers of ethylene, simultaneously possessing a high degree of swelling and high resistance to cracking under load and which is especially suitable for processing by extrusion and blown.

Consequently, the invention relates to polymers of ethylene, having a degree of swelling (TGat least 1.4; resistance to cracking under stress (ESCR) at least 55 hours and the flow index (MI5that is at least 0.2 g/10 min.

One of the essential characteristics of polymers of ethylene according to the invention, therefore, is to combine a high degree of swelling with high resistance to cracking under stress.

The degree of swelling of polymers of ethylene according to the invention is measured by extrusion at 190oC and at a velocity gradient of 100 s-1polymer of ethylene through a die plate with a length of 30 mm and a diameter of 2 mm and at a constant speed of extrusion, and by measuring the shift of the piston required for extruding rod with a length of 70 mm, the Degree of swelling is determined by the ratio where "e" denotes the shift of the piston, expressed in mm Cylinder and piston rheometer used for this measurement, meet the requirements of the Sabbath./P> Resistance to cracking under stress of the polymer of ethylene is measured according to the following method. From a sheet of polymer of ethylene press 10 plates of dimensions 125 mm x 12.7 mm x 3.2 mm they make two cuts: the first is a length of 60 mm from one end of the plate, and the second length of 15 mm at the other end of the plate. Slotted plate is subjected to a constant force bend value 7.36 H, which corresponds to the voltage, which is largest below the voltage threshold of the plastic yield strength, and simultaneously immersed in a solution of surface-active substances containing 3 ml nonylphenoxy-poly(ethyleneoxy)of ethanol per liter of water, at a temperature of 60oC. Note the time after which the samples are broken, and calculate the average time corresponding to the gap 50% of the samples.

In the present invention, the phrase "ethylene polymers" refers to homopolymers of ethylene and copolymers of ethylene with at least one of the co monomer. The most preferred copolymers of ethylene. As co monomer can be called alpha-olefins containing 3 to 8 carbon atoms. Preferred butene, hexene, and mixtures thereof. The content of the co monomer in the polymer of ethylene is usually at least 0.1 wt.%, in particular ponie of co monomer is not more than 5 wt.% the most typical.

Ethylene polymers according to the invention typically have a flow index, measured at 190oC under a load of 5 kg according to the norms of ACTM D 1238 - Condition P (1986) (below denoted as MI5at least equal to 0.3 g/10 min, in particular at least 0.6 g/10 minutes Usually MI5does not exceed 10 g/10 min, most often does not exceed 5 g/10 min and preferably does not exceed 5 g/10 min.

Preferred ethylene polymers according to the invention, moreover, are characterized by dynamic viscosity , expressed in rpas and measured velocity gradient of 100 s-1at 190oC, such that the ratio

< / BR>
at least equal to 0.55. Preferably this ratio is at least 0.59, and especially preferred values of at least 0.61. In most cases, this ratio is at most 0.73 and most often it is at most 0.70.

Ethylene polymers according to the invention usually have a standard volume weight (or density), measured according to the standard ISO 1183 (1987), equal to at least 945 kg/m3in particular at least 950 kg/m3moreover , the preferred value at least equal to 952 kg/m3. Standard bulk most 958 kg/m3.

The invention also relates to various methods of producing the above polymer of ethylene.

In the first method of obtaining a polymer of ethylene according to the invention using a solid catalyst containing titanium and zirconium as the active elements in the polymerization in two successive reactors.

The first method of obtaining is primarily in the polymerization of ethylene, if necessary with one or more comonomers, in two successive reactors in the presence of a solid catalyst containing titanium and zirconium in a molar ratio of Zr/Ti is at least equal to 2, and socializaton, and in the first reactor serves ethylene, in case you need comonomer and/or hydrogen, the solid catalyst and socialization; the reaction mixture from the first reactor is transferred to the second reactor and the second reactor, in addition, impose ethylene and, if necessary, comonomer. Preferably the hydrogen is injected in at least one of the two reactors.

The solid catalyst used in the first method according to the invention, preferably comprises 0.5-10 wt.% titanium (preferably 1-6 wt.%), 5-40 wt.% Zirconia (preferably 10-25 wt.%)wt.% magnesium (preferably 5-15 wt. %) and 0.5-10 wt.% aluminum (preferably 1-3 wt.%). The rest consists of organic groups used reagents, particularly of the CNS and alkyl groups. The halogen preferably is chlorine.

The ratio of Zr/Ti in the solid catalyst is preferably at least 2.5, and especially preferred values of at least 3. The ratio of Zr/Ti is not usually higher than 10, mostly not more than 8, with a preferred value of at most 6.

In the second method of obtaining a polymer of ethylene according to the invention using a mixture of two solid catalysts, and the first contains one active element, namely titanium, and the second contains two active element, namely titanium and zirconium, in the polymerization in two successive reactors, and socialization, and in the first reactor serves ethylene, in case you need comonomer and/or hydrogen, the first and second solid catalysts and socialization; reaction medium of the first reactor is transferred to the second reactor and the second reactor, in addition, enter ethylene and, if necessary, comonomer and/or hydrogen.

The second method of producing polymers of ethylene according to the invention consists sledovatelno installed reactors, in the presence of the first solid catalyst formed mainly from 10-30 wt.% titanium, 20-60 wt.% halogen, 0.5-20 wt.% magnesium and 0.1-10 wt.% aluminum; a second solid catalyst consisting mainly of 0.5-10 wt.% titanium, 5-40 wt. % zirconium, 20-80 wt.% halogen, 1-30 wt.% magnesium and 0.5-10 wt. % aluminum. Preferably, the hydrogen is injected in at least one of the two reactors.

Two solid catalyst, if necessary, can be pre-mixed prior to implementation of the method of polymerization. Premixing it is advisable to carry out at room temperature.

Preferably, the first solid catalyst consists essentially of 15-20 wt. % titanium, 30-50 wt.% halogen, 1-10 wt.% magnesium and 0.5-5 wt.% aluminum. The rest consists of organic groups of reagents used, particularly of the CNS and alkyl groups. Halogen is typically chlorine.

Most often, the second solid catalyst consists essentially of 1-6 wt.% titanium, 10-25 wt.% zirconium, 40-60 wt.% halogen, 5-15 wt.% magnesium and 1-3 wt. % aluminum. The rest consists of residual organic groups derived from the used reagents, particularly of the CNS and alkyl groups. In most of the congestion is usually used in such quantities, so that the molar ratio of titanium derived from the first solid catalyst, titanium, derived from the second solid catalyst comprised of at least 1, in particular at least 1.25, preferably values of at least 1.50. The ratio is usually at most 10, predominantly at most 5, and the preferred value of at most 4.

Acetalization used in the first or second method may be any known in the prior art of socialization, especially alyuminiiorganicheskikh connection. As examples trialkylaluminium compounds, especially such an alkyl group containing up to 20 carbon atoms, preferably 2-8 carbon atoms), such as triethylaluminium and triisobutylaluminum. Preferred triethylaluminium.

According to a particular method of implementation, one or more solid catalysts used in the first and second methods for producing polymers of ethylene according to the invention, obtained by the interaction in the first stage, oxygen-containing magyarkanizsa compounds with oxygen-containing technologicheski connection and possibly oxygen-containing zitkova complex in the second stage using halogenated alyuminiiorganicheskikh compounds of General formula

AlRnX3-n,

in which R is a hydrocarbon radical, X denotes a halogen and "n" has a value of less than 3, for the deposition of liquid complex in the form of solid catalyst.

In the present invention, the term "oxygen-containing magyarkanizsa connection see connection comprising at least one sequence of relations magnesium-oxygen-organic radical per atom of magnesium. Organic radical usually includes up to 20 carbon atoms and, mainly, to 10 carbon atoms, preferably 2-6 carbon atoms. The organic radical may be selected from among alkyl (linear or branched), alkenyl, aryl, cycloalkyl, arylalkyl, alcylaryl, acyl radicals and their substituted derivatives. The best results are achieved when using alkoxides of magnesium. Preferred dialkoxy magnesium, especially deatiled magnesium.

The term "oxygen-containing titanium or circinelloides connection see connection comprising at least one sequence of links titanium (or zirconium)-oxygen-organic radical per atom of titanium or zirconium. Organic radical corresponds to meedeniya tetravalent titanium or zirconium. Of the oxygen-containing titanium or circinelloides compounds can be called alkoxides, phenoxide, oxoalkoxide, condensed alkoxides, carboxylates and enolate. The best results are achieved using alkoxides. Preferred tetraethoxide titanium or zirconium, in particular tetrabutyl titanium or zirconium.

The first stage of obtaining the solid catalyst is in the cooking liquid complex by interaction of the oxygen-containing magyarkanizsa compounds with oxygen-containing technologicheski connection and, if a solid catalyst also includes zirconium, oxygen-containing circulatorysystem connection. The reaction can be carried out in the presence of a diluent. The diluent is usually chosen among linear or branched alkanes or cycloalkanes containing up to 20 carbon atoms. Well suited hexane.

The amount of oxygen-containing technologicheskogo connection is usually at least 0.01 mole of titanium used per mole of magnesium, in particular, at least 0.02 mol, with a preferred value of at least 0.05 mole. The number is usually at most 20 mol of titanium per mole espaa. The amount of oxygen-containing circinelloides connection then depends on the desired molar ratio of Zr/Ti.

The purpose of the second stage of obtaining a solid catalyst, which is called the stage of deposition, is to reduce the valence of the transition metal with simultaneous halogenoalkanes oxygen magyarkanizsa compounds, oxygen-containing technologicheskogo connection and, if necessary, oxygen circinelloides connection, i.e. to replace CNS groups present in these compounds, halogen-free so that the liquid complex obtained in the first stage, was precipitated in the form of solid catalyst. Restoration and halogenoalkane simultaneously performed using halogenated alyuminiiorganicheskikh connection, acting as a restorative-halogenation agent, causing the precipitation of the solid catalyst.

Treatment with halogenated alyuminiiorganicheskikh connection at the stage of deposition is carried out by introducing into contact with the liquid complex obtained in the first stage, with halogenated alyuminiiorganicheskikh connection, if this is Lex.

Halogenated alyuminiiorganicheskikh connection preferably corresponds to the formula AlRnX3-nin which R stands for a hydrocarbon radical with the number of carbon atoms to 20 and preferably up to 6. The best results are achieved when R denotes a linear or branched alkyl radical. X usually represents chlorine. Preferably "n" is not greater than 1.5, mostly less than 1. Preferred ethylaminoethanol or sibutraminegeneric.

The amount of halogenated alyuminiiorganicheskikh connection is usually at least 0.5 mol of aluminium used per mole of titanium or zirconium, preferably at least 1 mol, and the most common value of at least 2 mol, this number is usually at most 50 moles of aluminum per mole used titanium and zirconium, in particular at most 30 moles, preferably a value of not more than 20 moles.

After the stage of deposition of the liquid complex with halogenated alyuminiiorganicheskikh connection get a solid catalyst consisting of gamehendge sediment (and components of aoademy of the liquid complex) shoesmost, partially restored and/or partially halogenated compounds. We are talking about chemically related complexes, the products of chemical reactions, not the product obtained by mixing or phenomenon of adsorption. In fact, one or another of the components of these complexes cannot be separated using physical methods of separation.

Containing titanium and zirconium solid catalyst obtained according to the above private cooking method allows, if it is used for the polymerization of olefins in two successive reactors, to obtain polyolefins, other than the ethylene polymers according to the invention. Therefore, the invention also relates to a method for the polymerization of olefins, according to which will polimerizuet olefin, if necessary, with one or more comonomers in two successive reactors in the presence of a solid catalyst containing titanium and zirconium in a molar ratio of Zr/Ti is at least 2, and socializaton, and in the first reactor an olefin and, if necessary, comonomer and/or hydrogen, the solid catalyst and socialization; reaction medium of the first reactor is transferred to the second reactor, and but by reacting in the first stage, oxygen-containing magyarkanizsa compounds with oxygen-containing technologicheski compound and oxygen-containing circulatorysystem connection prior to the formation of liquid complex, followed by treatment of the above-mentioned liquid complex in the second stage, using halogenated alyuminiiorganicheskikh compounds of General formula AlRnX3-nin which R is a hydrocarbon radical, X denotes a halogen and "n" indicates a value less than 3, for the deposition of liquid complex in the form of a solid catalytic complex. The method allows to obtain high performance vysokoorganizovannyye polymers.

The olefin may be selected from among olefin containing 2 to 20 carbon atoms, and preferably 2-6 carbon atoms, such as ethylene, propylene, 1-butene, 4-methyl-1-penten and 1-hexene. Well suitable ethylene, 1-butene and 1-hexene. Particularly preferred ethylene. Comonomer can be selected among the above-mentioned olefins and among diolefines containing 4-20 carbon atoms. Needless to say that comonomer introduced into the second reactor may be different from that which is introduced into the first reactor.

A mixture of two solid catalysts used in the second method of obtaining the ethylene polymer according to the invention, can also be used in other ways polymerization of olefins in a single reactor isprimarily olefins, including:

(a) a first solid catalyst consisting mainly of 10-30 wt.% titanium, 20-60 wt.% halogen, 0.5-20 wt.% magnesium and 0.1-10 wt.% aluminum

(b) a second solid catalyst consisting mainly of 0.5-10 wt.% titanium, 5-40 wt.% zirconium, 20-80 wt.% halogen, 1-30 wt.% magnesium and 0.5-10 wt.% aluminum; and

(C) socialization.

Using a mixture of two solid catalysts allows you to quickly modify the properties of the obtained polymer due to selection of the composition of the above mixture.

In the third method of obtaining the ethylene polymer according to the invention using a solid catalyst containing chromium as the active element on the media.

The third way of obtaining the ethylene polymer according to the invention is, in particular, in the polymerization of ethylene and, if appropriate, with one or more comonomers in a single reactor in the presence of a solid catalyst comprising chromium on a medium containing at least two components selected among silicon oxide, aluminum oxide and aluminum phosphate, if necessary in the presence of socializaton and/or hydrogen.

The fourth method of obtaining the ethylene polymer according to Itoh consecutive reactors in the presence of the solid catalyst, includes chrome on a medium containing at least two components selected from silicon dioxide, aluminum oxide and aluminum phosphate, and socializaton, and in the first reactor serves ethylene, in case you need comonomer and/or hydrogen, and a solid catalyst, reaction medium of the first reactor is transferred to the second reactor, the second reactor, in addition, impose ethylene and, if necessary, comonomer and/or hydrogen, and socialization is present in at least one of the two reactors. Socialization preferably used only in the second reactor.

The solid catalyst used in the third and fourth methods for producing polymers of ethylene according to the invention may be obtained known by impregnation of a carrier in the form of a powder with an aqueous or organic solution of chromium compounds with subsequent drying in an oxidizing atmosphere. With this purpose you can use the chromium compound selected from water soluble salts, such as oxides, acetate, chloride, sulfate, chromate and bichromate, in the form of an aqueous solution or such as acetylacetonate, in the form of an organic solution. After impregnation of the carrier with the chromium compound impregnated carrier is usually actorentry chrome. The solid catalyst according to the invention can also be obtained by mechanical mixing of media in the form of a powder with solid chromium compound, for example with chromium acetylacetonate. Then this mixture can be productivitate at a temperature below the melting temperature of the compounds of chromium over traditional activated, as described above. In the solid catalyst used in the third and fourth methods, chromium is usually found in quantities varying from 0.05 to 10 wt.%, preferably 0.1-5 wt.%, mostly 0.25-2 wt.% chromium, calculated on the total weight of the solid catalyst.

Socialization, which can be used in the third method, but must be used in at least one reactor in the fourth method according to the invention, can be selected among aluminum - or boron compounds. The best results are achieved using organoboron compounds, as they can enhance the catalytic activity. As organoboron compounds can be used compounds trialkylborane, alkyl chain containing up to 20 carbon atoms. Usually preferred such compounds, the alkyl chains are linear and contain up to Moho of socializaton is usually 0.02 to 50 mmol per liter of solvent, diluent or reactor volume, and preferably 0.2-2.5 mmole per liter.

The medium used in the third and fourth methods of obtaining the polymer of ethylene according to the invention, has preferably a specific surface area of at least 100 m2/g, in particular at least 180 m2/g, with the most favorable values of at least 220 m2/g Specific surface often is at most 800 m2/g, mainly at most 700 m2/g, with the usual amount not exceeding 650 m2/g Specific surface area (SS) of the carrier is measured according to the volumetric BET method, the standard rate of UK BS 4359/1 (1984).

The medium used in the third and fourth methods of the present invention typically has a crystallization temperature not less than 700oC, such as, for example, at least 1000oC. the crystallization temperature of the medium determined by exposing the sample carrier heat treatment at different temperatures (500oC, 700oC, 800oC, 950oC, 1050oC) and then after each heat treatment, analyzing the sample by x-ray diffraction.

The medium used in the third and fourth method is the recommended value is at least 2.2 cm3/g pore Volume is usually at most 5 cm3/g, in particular at most 4.5 cm3/g, with an average size not exceeding 4 cm3the Volume of pores (VP) represents the sum of the pore volume formed by pores of radius less than or equal to 75 as measured according to the method of penetration of nitrogen (BET) according to the method described in the standard UK BS 4359/1 (1984), and pore volume, measured by the method of mercury penetration using paramera type PORO 2000, manufactured in the sale of the company CARLO ERBA CO under standard conditions of Belgium NBN In 05-202 (1976). Good results can be obtained when the specific surface (SS) and pore volume (VP) of the media respond to the following value:

SS<(VP x 564-358),

in which SS and VP respectively represent the number of new values of specific surface, expressed in m2/g, and pore volume, expressed in cm3/,

The medium used in the third and fourth ways, if it contains only two of the above components, preferably contains silicon dioxide and aluminum oxide in a molar ratio of 0.01-99 (preferably 0.05-20), silicon dioxide and aluminum phosphate in a molar ratio of 0.01-99 (preferably 0.05-20), aluminum oxide and aluminum phosphate in aluminia (Y) and aluminum phosphate (Z) in a molar ratio of

(X):(Y):(Z)=(10-95):(1-80):1-85),

and mainly(20-80):(1-60):(5-60). If necessary, the medium may contain, in addition, titanium. The amount of titanium in the media, expressed in a molar amount of TiO2in relation to the media of the solid catalyst containing silicon dioxide, aluminum oxide, aluminum phosphate and titanium dioxide, is usually an amount at least equal to 0.1 mol. %, preferably 0.5 mol.%; the most common values of at least 1 mol. % Number of titanium, expressed in molar content of TiO2often not more than 40 mol.%, mostly not more than 20 mol.%, and

recommended values of at most 15 mol.%

The medium used in the third and fourth methods, which use a solid chromium catalysts, usually found in the form of powder, grains which have a diameter of 20-200 μm. He usually has an apparent specific gravity greater than or equal to 50 kg/m3in particular, 100 kg/m3; apparent specific gravity is usually the maximum is 500 kg/m3typically 300 kg/m3. The apparent specific gravity is measured by the free outflow according to the following method: in a cylindrical vessel with a volume of 50 cm3fill the powder analyzed Nausicaa vessel. Then weigh the filled powder and leveled with a straight Reiki vessel, subtract the tare and the result (expressed in grams) divided by 50.

A special way of getting media used in the third and fourth methods, consists in mixing in the first stage of alcohol, water, silicon alcoholate and acid in such quantities that the molar ratio of water to silicon was 2-50; in addition to the resulting hydrolytic environment in the second stage, the acidic solution of an aluminium compound and a solution of a source of phosphate ions and in the third stage, the agent deposition to obtain a precipitate; washing in the fourth stage the obtained precipitate with water and then with an organic liquid, and then drying it at the fifth stage by distillation to obtain a powder and annealing of the powder.

The alcoholate of silicon used in the first stage of a private way of getting the media preferably contains CNS group with 1-20 carbon atoms. Recommended CNS group of aliphatic type, especially the group of saturated aliphatic, unsubstituted type. Well suitable alcoholate of silicon are tetraethyl, tetramethrin, tetraisopropyl cream is Holocene media alcohol is the dissolution of the silicon alcoholate. Preferred linear aliphatic alcohols. As examples, ethanol, isopropanol and methanol. The preferred ethanol. Preferably use alcohol, a hydrocarbon group which corresponds to that of CNS group used alcoholate of silicon.

The first stage is preferably carried out at acidic pH values and it includes, on the one hand, the introduction of water, acid, silicon alcoholate and alcohol, and the temperature during the administration of less than or equal to 30oC (in particular below 20oC, usually around 10oC, and recommended temperature above 0oC), and, on the other hand, exposure (aging) thus obtained reaction mixture at a temperature at least equal to the 20oC and below the boiling point of the medium (for example, when 30-100oC, and the normal temperature of 40-80oC and any recommended 50-70oC) to replace at least part of the CNS group alcoholate of silicon hydroxyl groups, without causing gilotinirovaniya or deposition of silicon dioxide. In the first stage, the pH value of the reaction medium is usually lower than 3, preferably 0.5-2.5, such as about 1. Used on the first stud is sotoi acid, phosphoric acid or sulfuric acid. Particularly well suited hydrochloric acid. Preferably, the maturation is carried out at a temperature above the temperature at which the reagents are introduced. Maturation is intended to implement the partial hydrolysis and condensation of silicon alcoholate.

The second stage of a private way of getting the media is adding to the environment that emerge from the first stage, the acidic solution of an aluminium compound and a solution of a source of phosphate ions. The aluminum compound may be selected from inorganic salts of aluminum and aluminum alcoholate. Recommended alcoholate of aluminum containing linear saturated unsubstituted aliphatic groups. Aliphatic group preferably containing 1-20 carbon atoms. The alcoholate of aluminum, CNS group which corresponds to the one used alcoholate of silicon, are particularly well suited. Most preferred are the nitrate and aluminium chloride. Under the source of phosphate ions understand any compound capable of forming phosphate ions. Especially recommended are the inorganic phosphate salts, ethers ether phosphate salts, and phosphoric acid. Preferably use is certain, to avoid heating medium, for example, at a temperature below 30oC, usually lower than or equal to 20oC, for example, at 0 to 10oC,

The third stage private way of getting the media is in the sediment under the action of the agent deposition, which may be selected from any of compounds able to cause coprecipitation of the reagents used in the first and second stage (hydrolyzed and partially condensed alcoholate of silicon originating from the first stage and defined above; a compound of aluminum and a source of phosphate ions in the form of a mixed oxide of silicon, aluminum and phosphorus. As examples of the agent deposition can be called ethylene oxide, ammonium carbonate and ammonium hydroxide. It is preferable to use an aqueous solution of ammonium hydroxide. pH environment coprecipitation is usually higher than or equal to 5, usually greater than or equal to 6; it is usually below 11 and recommended values below 10. Preferably, the pH-value constant support when the value 6-10, for example 8, for the entire duration of co-precipitation.

In the fourth stage private way of getting media water rinse is usually that the sediment is introduced into contact with a quantity of water sufficient to UD is swetnam adequate way, for example, by centrifugation or by filtration. Preferably carry out the centrifugation. Then water-washed precipitate is subjected to washing with an organic liquid, the purpose of which is to remove water that penetrates the sediment. Organic liquid preferably has a vaporization temperature below 120oC, usually below 100oC, for example, 70-90oC. Used organic liquids are alcohols, ethers, or their mixtures. Preferred alcohols, especially those containing 1-4 carbon atoms. Well suited isopropanol.

The washed precipitate is then, at the fifth stage private way of getting the media is subjected to drying by atomization or distillation, preferably azeotrope to evaporate the water and organic liquid that is not removed previously, to obtain a powder carrier.

In the drying to produce a powder carrier, which is subjected to calcination. The purpose of annealing is to remove at a high temperature organic impurities in the powder. The calcination is usually continued until constant weight of the powder, completely avoiding crystallization of the powder. The calcination can be performed in the air (preferred and powder. The temperature is usually 300-1500oC, usually 350-1000oC, preferably 400 to 600oC.

When using a carrier selected from binary media SiO2-AlPO4; Al2O3-AlPO4and of the three media SiO2-Al2O3-AlPO4such as described above in the method of polymerization of olefin in two reactors arranged in series, you can also obtain the polyolefin other than the polymer of ethylene according to the invention. Consequently, the invention relates also to a method for the polymerization of olefins, according to which will polimerizuet olefin, if necessary, with one or more comonomers, in two reactors arranged in series in the presence of a solid catalyst comprising chromium on the media selected among binary media SiO2-AlPO4; Al2O3-AlPO4and three carriers SiO2-Al2O3-AlPO4and socializaton, and in the first reactor serves ethylene and, if necessary, comonomer and/or hydrogen, the solid catalyst; reaction medium of the first reactor is transferred to the second reactor, the second reactor, in addition, impose ethylene and, if necessary, samanaikaiselle according to the invention can be carried out according to any known method in the solution of solvent, which may be with the olefin in the liquid state, or in suspension in a hydrocarbon diluent, or in gas phase. Good results are achieved when the suspension polymerization.

The principle of polymerization in two consecutive reactors described in European patent application EP 603 935 (Solvay). Installation can obviously include more than two reactors connected in series. Methods of polymerization in two successive reactors preferably implemented to be used in the second reactor, the polymerization conditions (temperature, concentration of the transfer agent (chain), such as hydrogen, the concentration of possible co monomer concentration possible socializaton) that are different from those used in the first reactor. So, obtained in the second reactor polymer has a flow index that is different from the product in the first reactor. Consequently, it is possible to do so that the flow index obtained in the first reactor, lower than that obtained in the second reactor. On the contrary, in the first reactor can be obtained higher yield than that obtained in the second reactor.

The following examples are intended for Illus the methods for measuring these quantities are explained below;

MI2= flow index of the polyethylene measured at 190oC under a load of 2.16 kg, according to the standard ACTM D 1238 (condition E) (1986).

MI5= flow index of the polyethylene measured at 190oC under a load of 5 kg according to the standard ACTM D 1238 (condition P) (1986).

MVS = standard volume weight polyethylene, expressed in kg/m3and measured according to the standard ISO 1183 (1987).

= dynamic viscosity of the polyethylene expressed in rpas and measured velocity gradient of 100 s-1at 190oC.

ESCR = resistance to cracking under load, expressed in hours and measured by the following method: from a sheet of ethylene polymer is pressed ten plates with dimensions 125 mm x 12.7 mm x 3.2 mm they make two cuts: the first - in 60 mm from one end plate, the second is 15 mm at the other end of the plate. Slotted plate is exposed to the constant efforts of the bend 7.36 H, corresponding to a voltage whose magnitude is below such threshold plastic fluidity, and simultaneously immersed in a solution of surface-active substances containing 3 ml nonylphenoxypoly(ethylenoxy)of ethanol per liter of water, at a temperature of 60oC. Note the time after which obrein swelling of the ethylene polymer (dimensionless).

The measurement method is extrusion at 190oC and at a velocity gradient of 100 s-1polymer of ethylene through a die plate with a length of 30 mm and a diameter of 2 mm and at a constant speed of extrusion, and measuring the shift of the piston required for extruding rod with a length of 70 mm, the Degree of swelling is determined by the ratio

< / BR>
where "e" denotes the displacement of the piston, expressed in mm.

The cylinder and piston rheometer used for this measurement, meet the requirements of the rheometer used for measuring flow index according to the standard ACTM D 1238 (1986).

P = the productivity of the solid catalyst, expressed in kg of the obtained polyethylene per gram used titanium.

EXAMPLE 1 (reference)

This example produces the ethylene polymer in two reactors connected in series by using a catalyst based on titanium and measure its degree of swelling and its resistance to cracking under stress.

A. Preparation of the solid catalyst

For 4 hours at 150oC deatiled magnesium is administered in cooperation with tetrabutyltin titanium in such quantities that the molar ratio of titanium to magnesium is 2. Then glorious and Alicante, that the molar ratio of aluminum to magnesium is equal to 6.5, for 90 minutes at 45oC. the Thus obtained solid substance contains 15.8 wt.% titanium, 36.0 wt.% chlorine, 2.2 wt.% aluminum and 4.4 wt.% magnesium.

B. Polymerization of ethylene in two reactors

Ethylene will polimerizuet in the installation, including two consecutively installed reactor. In the first reactor is continuously injected hexane, triethylaluminium as socializaton, ethylene and hydrogen in a molar ratio of hydrogen/ethylene = 0.27 and the solid catalyst obtained in p. A. Temperature constant support at 85oC. Environment polymerization of the first reactor was continuously extracted and transferred to the second reactor, in which, in addition, impose ethylene, hydrogen in a molar ratio of hydrogen/ethylene = 0,0085 and butene in a molar ratio of butene/ethylene 0,31. The temperature in the second reactor is 70oC. Performance P is 200. The resulting polymer has the following characteristics:

MI5= 1,3;

= 15400;

TG= 1,34;

ESCR = 128;

MVS = 956.

< / BR>
The resulting polymer has a degree of swelling below 1.4, whereas the ethylene polymers according to the invention have a degree of swelling of at least 1.4.

A. Preparation of the solid catalyst

For 4 hours at 150oC deatiled magnesium is administered in cooperation with tetrabutyltin titanium and tetrabutyltin zirconium in such quantities that the molar ratio of Ti/Mg is equal to 0.6 and the molar ratio of Zr/Ti is equal to 1.2. Then glorious and precipitate the resulting reaction product by introducing it into contact with a solution of isobutyleneisoprene in such a quantity that the molar ratio of Al/Mg is 11, at 45oC. the Solid catalyst is mixed with tetraisopropyl titanium in the amount of 150 g per kg of the solid catalyst. Thus, the obtained solid substance contains 6.4 wt.% titanium, 12.6 wt.% zirconium, 55.2 wt.% chlorine, 2.5 wt.% aluminum and 5.8 wt. % magnesium.

B. Polymerization of ethylene in a reactor

Ethylene will polimerizuet in a single reactor. There is injected hexane, triisobutylaluminum as socializaton, ethylene and hydrogen in a molar ratio of hydrogen/ethylene 0,09 and obtained in the solid catalyst. Enter butene in a molar ratio of butene/ethylene = 0.07. Temperature constant support in = 1,1;

= 18300;

TG= 1,59;

ESCR = 38;

MVS = 954.

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The resulting polymer has a resistance to cracking under load below 55 hours, whereas the ethylene polymers according to the invention have a resistance to cracking under load of at least 55 hours.

EXAMPLE 3 (reference)

In this example produces a polymer of ethylene in a single reactor using a catalyst based on chromium on the media from silicon dioxide and measure the degree of swelling and its resistance to cracking under stress.

A. Preparation of the solid catalyst

Use shopping catalyst EP 30 X company CROSFIELD, containing 1 wt. % chromium, deposited on silicon dioxide. The catalyst was calcined in the fluidized bed at 760oC for 12 hours in an atmosphere of dry air and get a solid catalyst.

B. Polymerization of ethylene in a reactor

Ethylene will polimerizuet in a single reactor. Into it enter isobutane, ethylene and hexene in a molar ratio of hexene/ethylene = 0.017 and the solid catalyst obtained in p. A. Total pressure in the reactor and the temperature constant support when the value of 4.2 MPa and 103oC, respectively. Received Pol,0.

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The resulting polymer has a resistance to cracking under load below 55 hours, while the ethylene polymers according to the invention have a resistance to cracking under load of at least 55 hours.

EXAMPLE 4 (according to the invention)

In this example produces a polymer of ethylene according to the invention using the first method of receiving according to the invention.

A. Preparation of the solid catalyst

For 4 hours at 150oC deatiled magnesium is administered in cooperation with tetrabutyltin titanium and tetrabutyltin zirconium in such quantities that the molar ratio of Ti/Mg = 0.4 and the molar ratio of Zr/Ti = 3. Then glorious and precipitate thus obtained reaction product by introducing it into contact at 45oC with a solution of isobutyleneisoprene in such a quantity that the molar ratio of Al/Mg = 8.4. Thus, the obtained solid substance contains 4.4 wt.% titanium, 14.9 wt.% zirconium, 50.2 wt.% chlorine, 2.4 wt.% aluminum and 8.0 wt.% magnesium.

B. Polymerization of ethylene in two reactors

Ethylene will polimerizuet in the installation, including two consecutive reactor. In the first reactor is continuously injected hexane, criticalities, obtained in p. A. Temperature constant support at 85oC. the Polymerization medium of the first reactor is continuously selected and transferred to the second reactor, in which, in addition, impose ethylene, hydrogen in a molar ratio of hydrogen/ethylene = 0.0125 and butene in a molar ratio of butene/ethylene = 0.2. The temperature in the second reactor is 80oC. Performance P is 213. The mass ratio of the polymer produced in the first reactor, the polymer produced in the second reactor is 45.6/54.4. The resulting polymer has the following characteristics:

MI5- 1,5;

= 12800;

TG= 1,49;

ESCR = 143;

MVS = 955.

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EXAMPLE 5 (according to the invention)

In this example produces a polymer of ethylene according to the invention using the second retrieval method according to the invention.

A. preparation of a mixture of solid catalysts

A. 1. Preparation of the first solid catalyst based on titanium

For 4 hours at 150oC deatiled magnesium is administered in cooperation with tetrabutyltin titanium in such quantities that the molar ratio of titanium to magnesium is 2. Then glorious and precipitate the resulting reaction product by introducing it into contact with SUP>oC. the Thus obtained solid substance contains 15.8 wt.% titanium, 36.0 wt.% chlorine, 2.2 wt.% aluminum and 4.4 wt.% magnesium.

A. 2. Preparation of the second solid catalyst based on titanium and zirconium

For 4 hours at 150oC deatiled magnesium is administered in cooperation with tetrabutyltin titanium and tetrabutyltin zirconium in such quantities that the molar ratio of Ti/Mg = 0.6 and the molar ratio of Zr/Ti = 2. Then glorious and precipitate the resulting reaction product by introducing it into contact with a solution of isobutyleneisoprene in such a quantity that the molar ratio of Al/Mg = 14, first, at 45oC, then at 60oC. the Thus obtained solid substance contains 5.4 wt.% titanium, 16.3 wt.% zirconium, 52.6 wt.% chlorine, 2.4 wt.% aluminum and 4.1 wt.% magnesium.

A. 3. Preparation of a mixture of

Obtained in p. A. 1. the solid is mixed with the obtained in p. A. 2. solid substance in such quantities that the molar ratio of titanium derived from the first solid catalyst, titanium, originating from the second solid catalyst is 1.5.

B. Polymerization of ethylene in two reactors

Ethylene will polimerizuet in the installation, including two raspolojeniea, ethylene and hydrogen in a molar ratio of hydrogen/ethylene = 0.32 and a mixture of solid catalysts obtained in p. A. Z. the Total pressure in the reactor and the temperature constant support when the value of 3.2 MPa and 85oC, respectively. The polymerization medium of the first reactor was continuously extracted and transferred to the second reactor, in which, in addition, impose ethylene, hydrogen in a molar ratio of hydrogen/ethylene = 0.0185 and butene in a molar ratio of butene/ethylene = 0.35. The total reactor pressure is 3.0 MPa. The temperature in the second reactor is 75oC. Performance P is 111. The resulting polymer has the following characteristics:

MI2= 0,32;

= 15300;

TG= 1,43;

ESCR = 109;

MVS = 956,4;

MI5= 1.5 g/10 min

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EXAMPLE 6 (according to the invention)

In this example produces a polymer of ethylene according to the invention using the third method of receiving according to the invention.

A. Preparation of the solid catalyst

A. 1.

To a solution of tetraethylene silicon in ethanol at a temperature of 10oC add water 1 M solution of hydrochloric acid to obtain a pH of 1. The quantities used are: 34.7 g of tetraethylene silicon, 41.7 g of ethanol, 18.9 g isC within 2 hours.

A. 2.

Simultaneously prepare an aqueous solution containing 62.5 g of hydrated ammonium nitrate, 17.1 g of phosphoric acid and 33.3 g of water. After that, the thus obtained solution is added to the obtained in p. A. 1. the reaction medium under vigorous stirring and a temperature of 10oC.

A. 3.

To 500 g of an aqueous solution of ammonium hydroxide to pH = 8, thermostatted at 10oC add received in p. A. 2. the mixture, maintaining the pH constant, equal to 8, to implement gilotinirovaniya. The gel is subjected to ripening at pH = 8 for 2 hours under stirring and at 60oC.

A. 4.

Then the gel is washed with water and then with isopropanol and get the suspension gel.

A. 5.

Obtained in p. A. 4. the gel is dried by atomization to obtain powder.

A. 6.

Obtained in p. A. 5. the powder is calcined in the fluidized bed by blowing dry air for 4 hours at 500oC. to produce a powder, comprising: 15.6 wt.% silicon, 15.1 wt.% aluminum; 16.3 wt.% of phosphorus.

A. 7.

Obtained in p. A. 6. the carrier is mixed with chromium acetylacetonate in such quantity that the mixture sodev for 2 hours while purging with dry air. After that its calcined in the fluidized bed at 600oC for 10 hours in a stream of dry air and get a solid catalyst, which has the following characteristics:

specific surface area = 407 m2/g;

pore volume = 2.20 cm3/g;

crystallization temperature of above 700oC.

B. Polymerization of ethylene in a reactor

Ethylene will polimerizuet in a single reactor. It is administered continuously isobutane, ethylene, hydrogen in a molar ratio of hydrogen/ethylene = 0.046 and hexene in a molar ratio of ethylene/hexene = 0.003 and obtained in the solid catalyst. The total pressure in the reactor and the temperature constant support when the value of 3.8 MPa and 107oC, respectively. The resulting polymer has the following characteristics:

MI5= 0,58;

= 18000;

TG> 1,5;

ESCR = 111;

MVS = 955,8.

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EXAMPLE 7 (according to the invention)

In this example produces a polymer of ethylene according to the invention using the fourth method of producing according to the invention.

A. Preparation of the solid catalyst

Using the solid catalyst of example 6, which is calcined in the fluidized bed at 815oC for 16 hours in dry air.

The first polymer (I)

In the autoclave with a capacity of 3 l equipped with a stirrer, enter 108 mg of catalyst. The polymerization temperature is brought to 80oC and constant support during the polymerization. Then there introducing ethylene. The partial pressure of ethylene maintain a constant with the value of 5.8 bar. Enter 6.7 g of hexene, then 0.67 g each time, when you get 50 g PE (for maintaining constant the ratio of hexene/ethylene). The ratio of hexene/ethylene = 0.11. After 68 minutes, the autoclave Tegaserod to a pressure of 6 bar. Get 162 g of polymer (I).

Obtaining a second polymer (II)

To the autoclave was added 1 l of isobutane. The temperature is brought up to 98oC and her constant support during the time of polymerization. Then enter one dose of hydrogen to obtain a molar ratio of hydrogen/ethylene in the liquid phase = 0.22. After that enter socialization (createvar) in the autoclave in such an amount that the molar ratio criativos/chrome is 3.8. The partial pressure of ethylene maintain a constant with the value of 3.5 bar to more number of 162 g of polymer (II). After degassing in the autoclave get 324 g of a mixture of polymers (I) and (II). The catalyst has an activity 33000 and 93000 according to the

The properties of the polymer after pelleting the following:

MI5= 0,49;

= 14000;

TG= 1,9;

MVS = 954,4.

about

1. Homo - or copolymers of ethylene, characterized in that have a degree of swelling at least 1,4, resistance to cracking under load at least 55 h and the flow index of at least 0.2 g/10 min.

2. Homo - or copolymers of ethylene under item 1, characterized in that have a flow index (MI5), expressed in g/10 min, and dynamic viscosity , expressed in DPA and measured velocity gradient of 100 s-1at 190oC, corresponding to the ratio

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3. Homo - or copolymers of ethylene under item 1 or 2, characterized in that have a standard volume weight 952 - 958 kg/m3.

4. Homo - or copolymers of ethylene according to any one of paragraphs.1 to 3, characterized in that they contain 0.1 to 10 wt.% the co monomer selected among butene, hexene, and mixtures thereof.

5. The way to obtain Homo - or copolymers of ethylene according to any one of paragraphs.1 to 4 by the polymerization of ethylene, if necessary, with one or more comonomers in two reactors connected in series in the presence of the solid catalyst, characterized in that use solid to the first reactor serves ethylene, in case you need comonomer and/or hydrogen, the solid catalyst and socialization, reaction medium of the first reactor is transferred to the second reactor and the second reactor, in addition, impose ethylene, in case you need comonomer and/or hydrogen.

6. The method according to p. 5, characterized in that the solid catalyst contains 0.5 - 10 wt. % titanium, 5 to 40 wt.% Zirconia, 20 to 80 wt.% of halogen, 1 to 30 wt.% magnesium and 0.5 - 10 wt.% aluminum.

7. The way to obtain Homo - or copolymers of ethylene according to any one of paragraphs.1 to 4 by the polymerization of ethylene, if necessary, with one or more comonomers in two reactors connected in series in the presence of a solid catalyst, wherein the polymerization is carried out in the presence of the first solid catalyst containing titanium as the only active element, and the second solid catalyst containing titanium and zirconium as the active elements, and socializaton, and in the first reactor is injected ethylene, in case you need comonomer and/or hydrogen, the first and second solid catalysts and socialization, reaction medium of the first reactor is transferred to the second reactor and the second reactor, in addition, introducing ethylene, localizator essentially consists of 10 - 30 wt.% titanium, 20 - 60 wt.% halogen, 0.5 to 20 wt.% magnesium and 0.1 - 10 wt.% aluminum, and the second solid catalyst consists essentially of 0.5 to 10 wt.% titanium, 5 to 40 wt.% Zirconia, 20 to 80 wt.% of halogen, 1 to 30 wt.% magnesium and 0.5 - 10 wt.% aluminum.

9. The method according to PP.5 and 7, characterized in that the use of a solid catalyst, which is obtained by introducing into the interaction in the first stage, oxygen-containing magyarkanizsa compounds with oxygen-containing technologicheski connection and possibly oxygen-containing circulatorysystem connection to obtain a liquid complex with subsequent treatment of the obtained liquid complex in the second stage using halogenated alyuminiiorganicheskikh compounds of General formula AlRnX3-nin which R is a hydrocarbon radical, X is halogen and n has a value of less than 3, and depositing a liquid complex in the form of a solid catalytic complex.

10. The way to obtain Homo - or copolymers of ethylene according to any one of paragraphs.1 to 4 by the polymerization of ethylene, if necessary, with one or more comonomers in the presence of a solid catalyst containing chromium on the media, and possibly in the presence of acatalyst the chrome on the media, containing at least two components selected from silicon dioxide, aluminum oxide and aluminum phosphate, possibly in the presence of socializaton and/or hydrogen, and the polymerization is carried out in one or two reactors.

11. The method according to p. 10, characterized in that will polimerizuet ethylene, if necessary, with one or more comonomers in two reactors arranged in series in the presence of a catalyst and localizator, and in the first reactor serves ethylene, in case you need comonomer and/or hydrogen and a solid catalyst, reaction medium of the first reactor is transferred to the second reactor, which is injected ethylene and, if necessary, comonomer and/or hydrogen, and socialization is in at least one of the two reactors.

12. The method according to p. 10 or 11, characterized in that the solid catalyst comprises 0.05 to 10 wt.% chromium and medium contains silicon dioxide (X), aluminum oxide (Y) and aluminum phosphate (Z) in a molar ratio of (X) : (Y) : (Z) = (10 - 95) : (1 - 80) : (1 - 85).

13. The method according to any of paragraphs.10 to 12, characterized in that socialization is dealkiller, and the alkyl radical contains up to 20 carbon atoms.

 

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FIELD: chemical industry, in particular two-component heterogeneous immobilized catalyst for ethylene polymerization.

SUBSTANCE: claimed catalyst includes alumina, mixture of transition metal complexes with nitrogen skeleton ligands (e.g., iron chloride bis-(imino)pyridil complex and nickel bromide bis-(imino)acetonaphthyl complex). According the first embodiment catalyst is prepared by application of homogeneous mixture of transition metal complexes onto substrate. iron chloride bis-(imino)pyridil complex and nickel bromide bis-(imino)acetonaphthyl complex (or vise versa) are alternately applied onto substrate. According the third embodiment catalyst is obtained by mixing of complexes individually applied onto substrate. Method for polyethylene producing by using catalyst of present invention also is disclosed.

EFFECT: catalyst for producing polyethylene with various molecular weights, including short chain branches, from single ethylene as starting material.

7 cl, 5 tbl, 27 ex

FIELD: olefin polymerization.

SUBSTANCE: invention relates to method for introducing of several catalysts in gas-phase or suspension reactor. Claimed method includes integration before introducing into single reactor of (a) solution, suspension or emulsion containing the first catalytic substance; and (b) solution, suspension or emulsion containing the second catalytic substance and optionally activator; followed by (c) introducing of (a) and (b) composition into single reactor in presence of hydrogen and one or more olefins wherein one polyolefin composition is formed.

EFFECT: polymers with wide bimodal molecular mass distribution.

14 cl, 3 ex

FIELD: polymerization catalysts and polymerization processes.

SUBSTANCE: high-activity ethylene (co)polymerization-appropriate supported titanium-based catalyst is composed of (A) supported catalytic component, notably titanium-containing active component on porous silica, containing at least one titanium compound, at least one magnesium compound, at least one alkylaluminum compound, at least one halide promoter, at least one electron-donor compound, and inert porous silica carrier, wherein halide promoter belongs to the class of compounds described by general formula F-R1[R2bX(3-b)], in which F represents oxygen-containing functional group reactive to organoaluminum compound, titanium compound, and hydroxyl groups; R1 bivalent C1-C6-aliphatic or aromatic grouplinked to functional group F; R2 hydrogen atom, unsubstituted or halogen-substituted C1-C6-alkyl, halogen-substituted C3-C6-cycloalkyl, or halogen-substituted C6-C10-aryl; b=0,1 or 2; and X represents fluorine, chlorine, or bromine atom; and (B) alkylaluminum cocatalyst. Invention also discloses catalyst preparation method and ethylene (co)polymerization process in presence of above-defined catalyst.

EFFECT: enabled preparation of catalyst with good morphology and flowability of particles, high catalytic activity, good sensitivity to addition of hydrogen, and ability to include comonomer; improved particle morphology of polymers.

15 cl, 2 tbl, 11 ex

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