Polyolefin compositions with high decolouration and impact resistance, and method of preparing said compositions

FIELD: chemistry.

SUBSTANCE: invention relates to polyolefin compositions which have high decolouration and impact resistance. The composition contains from 50 to less than 70 wt % crystalline propylene homopolymer, 13-28 wt % elastomeric ethylene and propylene copolymer and 10-22 wt % polyethylene. Total amount of the elastomeric copolymer and polyethylene in the composition is more than 30 wt %. The crystalline propylene homopolymer has polydispersity index ranging from 4 to 10 and amount of isotactic pentades (mmmm) measured using 13C-NMR method on a fraction which is insoluble in xylene at 25°C more than 97.5 mol %. The elastomeric ethylene copolymer is partially soluble in xylene at ambient temperature. The polymer fraction which is soluble in xylene has value of inherent viscosity, measured in tetrahydronaphthalene at 135°C, which ranges from 2 to 4 dl/g. Polyethylene has inherent viscosity ranging from 1 to 3 dl/g.

EFFECT: obtained polypropylene compositions have relatively low hardness, high impact resistance and high resistance to decolouration, which enables their use in the motor car industry, particularly in bumpers and interior finishing, packaging and household objects.

5 cl, 4 tbl, 6 ex

 

The present invention relates to polyolefin compositions having good characteristics of resistance to discoloration and impact resistance.

Polyolefin compositions according to the present invention find application in the automotive field, in particular in the bumpers and interior trim, Luggage items and household items.

As you know, isotactic polypropylene, although endowed with an exceptional combination of excellent properties, has the disadvantage of having insufficient impact resistance at relatively low temperatures.

According to the description of the prototype it is possible to eliminate the above drawback and to keep the resistance to discoloration (discoloration), without significantly affecting other properties of the polymer through the appropriate add rubbers and polyethylene to polypropylene.

For example, U.S. patent No. 4245062 discloses a method of obtaining a mixture of polypropylene and two different copolymers of propylene-ethylene, and one of these copolymers form, mainly kauchukopodobnoe phase. Thus obtained propylene polymers have good impact resistance at low temperature.

European patent application 86300 for the so called "songs of impact polypropylene" and discloses polypropylene copolymers with increased UD is reproject and high rigidity.

In U.S. patent No. 4521566 disclosed polypropylene composition having the following composition:

from 74 to 91% crystalline isotactic polypropylene

from 6,7% to 19% of an amorphous copolymer fraction of ethylene and propylene and

from 1.5 to 8.5% crystalline polyethylene containing from 50 to 98 wt.% ethylene and showing the crystallinity of the polyethylene type.

This composition demonstrates a relatively high stiffness and good impact resistance, but the resistance to discoloration is not as high as you want.

U.S. patent No. 4473687 discloses a polypropylene molding compositions of polypropylene, copolymer of ethylene-propylene and polyethylene in different proportions, and this composition has high hardness and high toughness.

In U.S. patent No. 4734459 disclosed polypropylene composition having good resistance to discoloration. According to the description of the specified document that is the prototype, you can increase the resistance to discoloration, replacing the ethylene-propylene copolymer rubber, ethylene-butenova-1 copolymer rubber.

Now unexpectedly found that it is possible to obtain a polypropylene composition, at the same time endowed with a relatively low stiffness, high impact resistance and high resistance obective is the air traffic management, receiving a polypropylene composition having a different ratio between the polymer components that demonstrate specific features.

Thus, a variant of the present invention includes a polypropylene composition comprising (percent by mass):

a) 50-77%, preferably between 50 and less than 70% of a crystalline propylene polymer having an amount of the isotactic pentad (mmmm), measured by the method of13C-NMR of fraction insoluble in xylene at 25°C, above which is 97.5 molar % and the index polydispersity from 4 to 10, preferably from 5 to 10, more preferably from 5.5 to 10;

b) 13-28%, more preferably 15 to 28% of an elastomeric copolymer of ethylene and propylene, the copolymer has a number of repeating units, derivatives of ethylene, 30 to 70%, preferably from 35 to 60% and partially soluble in xylene at ambient temperature, and the polymer fraction soluble in xylene at ambient temperature, has a value of the characteristic viscosity of from 2 to 4 DL/g; and

C) 10-22%, preferably from 10 to 20% of polyethylene having a value of the characteristic viscosity of from 1 to 3 DL/g, and optionally contains repeating units derived propylene, at less than 10%.

Used herein, the term "copolymer" refers to polymers with two different povtoreyko the links and polymers with a number of different repeating units in the chain more than two, for example trimers. The expression "ambient temperature" means a temperature of about 25°C. the Expression "crystalline propylene polymer" denotes in the present application is a propylene polymer having an amount of the isotactic pentad (mmmm), measured by the method of13C-NMR of fraction insoluble in xylene at 25°C above 70 molar %; the term "elastomeric" polymer means a polymer having a solubility in xylene at ambient temperature is above 50 wt.%.

The composition typically has a content of component (b) plus component (c) in an amount of at least 25 wt.%, preferably above 30 wt.%, and the total content of copolymerizing ethylene is at least 17 wt.%, preferably equal to or greater than 20 wt.%.

The composition typically has a value of speed of flow of the melt from 10 to 30, preferably from 10 to 20 g/10 minutes

The composition typically has a number of elastomeric copolymer (b)equal to or greater than the amount of the polyethylene (c), preferably the mass ratio of the copolymer (b) and polyethylene (c) is at least 1,2.

Typically, the composition of the present invention demonstrates the value of the modulus of bending of at least 800 MPa, preferably from 850 to 1250 MPa, the values of resistance to discoloration under load corresponding to the diameter obestsvechivaya region is e more than 1.50 cm in the fall of the plunger from a height of 30 cm and diameter obestsvechivaya area not more than 0.80 cm after the fall of the plunger from a height of 5 cm, the value of impact resistance Izod at 23°C for more than 16 kJ/m2and the value at 0°C for more than 10 kJ/m2.

The crystalline propylene polymer (a) selected from propylene homopolymer and copolymer of propylene containing less than 3 wt.% ethylene, or C4-C10α-olefin, or combinations thereof. Particularly preferred is a homopolymer of propylene.

Usually crystalline propylene polymer (a) shows a molecular weight distribution expressed by the ratio between srednevekovoi molecular weight and srednetsenovoj molecular mass, i.e. Mw/Mmdetermined by the GPC method, and is equal to 7,5 or more, in particular from 8 to 20, more preferably from 12 to 18.

Usually crystalline propylene polymer (a) demonstrates the value of z, the ratio of the average molecular weight to srednetsenovoj molecular mass, i.e. Mz/Mwmeasured by the GPC method, of at least a 3.5, preferably from 3.5 to 9.

Elastomeric copolymer of ethylene-propylene (b) may optionally contain a diene. The diene, when present, is usually a number from 0.5 to 10 wt.% relative to the weight of the copolymer (b). The diene may be paired or unpaired and selected, for example, from butadiene, 1,4-hexadiene, 1,5-hexadiene and ethylidene-norbornene-1.

The copolymer (b) shows the fraction insoluble in XI the OLE at ambient temperature, which is usually less than 45 wt.%, preferably up to 20 wt.%. Insoluble in xylene polymer fraction of the copolymer (b) is enriched with ethylene; the amount of ethylene is usually higher than 55 wt.%.

The polyethylene (c) is a crystalline or semi-crystalline and is selected from homopolymer of ethylene or copolymer of ethylene and propylene having an average content of co monomer is less than 10 wt.%. The values of the characteristic viscosity of the copolymer (c) are preferably within the range from 1.2 to 2 DL/g

The composition of the present invention is obtained by sequential copolymerization processes.

Thus, an additional aim of the present invention is a method for polyolefin compositions described above, and the method includes at least three successive stages of polymerization, with each subsequent stage polymerization is carried out in the presence of the polymeric material formed in the immediately preceding polymerization reaction, where the stage polymerization of propylene crystalline polymer (a) conduct, at least in one stage after stage copolymerization of mixtures of ethylene with propylene (and optionally a diene) elastomer polymer (b) and finally perform phase polymerization of ethylene to polyethylene (c). Stage polymerization can be applied in the led in the presence of a stereospecific catalyst of Ziegler-Natta. According to a preferred variant all stage polymerization is carried out in the presence of a catalyst containing trialkylaluminium compound, optionally an electron donor, and a solid catalyst component comprising a halide or halogen-alcoholate of Ti and an electron-donating compound, in the medium of anhydrous magnesium chloride. Catalysts having the above characteristics, are well known in the patent literature; particularly useful are the catalysts described in U.S. patent 4399054 and EP-A 45 977. Other examples can be found in U.S. patent 4472524.

The preferred polymerization catalyst is a catalyst of Ziegler-Natta containing solid catalytic component, including:

a) Mg, Ti and halogen and an electron donor (internal donor),

b) alkylamino compound, and optionally (but preferably),

C) one or more electron-donor compounds (external donor).

The internal donor is preferably selected from esters of mono - or dicarboxylic organic acids, such as benzoate, maleate, phthalates and some succinate. They are described, for example, in U.S. patent No. 4522930, European patent 45977 and international patent applications WO 00/63261 and WO 01/57099. Particularly suitable are the esters of phthalic acid and esters of succinic acid. Preferred alkylphenate, such as disob the Tyl, dioctyl and definiltely and benzylbutylphthalate.

Succinate preferably selected from succinates following formula (I):

where the radicals R1and R2identical or different, represent a C1-C20linear or branched alkyl, alkeline, cycloalkyl, aryl, arylalkyl or alcylaryl group, optionally containing heteroatoms; the radicals R3-R6identical or different, represent a hydrogen atom or a C1-C20linear or branched alkyl, alkeline, cycloalkyl, aryl, arylalkyl or alcylaryl group, optionally containing heteroatoms, and the radicals R3-R6that are attached to the same carbon atom can be linked together to form a cycle; with the proviso that when R3-R5simultaneously denote hydrogen, R6denotes a radical selected their primary branched, secondary or tertiary alkyl groups, cycloalkyl, aryl, arylalkyl or alcylaryl groups having from 3 to 20 carbon atoms; or the following formula (II):

where the radicals R1and R2identical or different, represent a C1-C20linear or branched alkyl, alkeline, cycloalkyl the data, aryl, arylalkyl or alcylaryl group, optionally containing heteroatoms, and the radicals R3denotes a linear alkyl group having at least four carbon atoms and optionally containing heteroatoms. Al-alkyl compounds used as a co-active catalysts contain Al-trialkyl, such as Al-triethyl, Al-triisobutyl, Al-tri-n-butyl, and linear or cyclic Al-alkyl compounds containing two or more Al atoms linked to each other through the O or N atoms, or a group of SO4or SO3. Al-alkyl compound is usually used in an amount such that the ratio Al/Ti was from 1 to 1000.

The external donor (c) may be of the same type or may be different from succinate formula (I) or (II). Suitable external electron-donor compounds include silicon compounds, ethers, esters, such as phthalates, benzoate, succinate, also has a structure different from the structure of the formula (I) or (II), amines, heterocyclic compounds and particularly 2,2,6,6-tetramethylpiperidine, ketones and simple 1,3-diesters of General formula (III):

where RIand RIIare the same or different and represents a C1-C18alkyl, C3-C18cycloalkyl or C7-C18aryl glad the Kala; RIIIand RIVare the same or different and represents a C1-C4alkyl radicals; or a simple 1,3-diesters in which the carbon atom in position 2 belongs to a cyclic or polycyclic structure consisting of 5, 6 or 7 carbon atoms and containing two or three of unsaturation. Ethers of this type are described in published European patent applications 361493 and 728769.

Preferred electron-donor compounds that can be used as external donors include aromatic silicon compound containing at least one bond of Si-OR, where R is a hydrocarbon radical. A particularly preferred class of external donor compounds include silicon compounds of the formula Ra7Rb8Si(OR9)cwhere a and b are integers from 0 to 2, c is an integer from 1 to 3 and the sum (a+b+c) is 4; R7, R8and R9represents a C1-C18hydrocarbon group, optionally containing heteroatoms. Particularly preferred silicon compounds in which a is 1, b is 1, c is 2, at least one of R7and R8selected from branched alkyl, alkenyl, alkilinity, cycloalkyl or aryl groups with 3-10 carbon atoms, optionally containing heteroatoms, and R9present is employed, a C 1-C10alkyl group, in particular methyl. Examples of such preferred silicon compounds are cyclohexyltrichlorosilane, tert-butyldimethylsilyl, tert-hexyltrimethoxysilane, cyclohexanedimethanol, 3,3,3-cryptochrome-2-ethylpiperidine-dimethoxysilane, diphenylmethylsilane, methyl-tert-butyldimethylsilyl, dicyclopentadienyliron, 2-ethylpiperidine-2-tert-butyldimethylsilyl, (1,1,1-Cryptor-2-propyl)metaldimension and (1,1,1-Cryptor-2-propyl)-2-ethylpiperidine. In addition, also preferred silicon compounds in which a is 0, c is 3, R8denotes a branched alkyl or cycloalkyl group, optionally containing heteroatoms, and R9denotes methyl. Particularly preferred specific examples of silicon compounds are (tert-butyl)2Si(OCH3)2, (cyclohexyl)(methyl)Si(OCH3)2, (phenyl)2Si(OCH3)2and (cyclopentyl)2Si(OCH3)2.

It is preferable to use electron-donating compound (c) in such a quantity to obtain a molar ratio between organoaluminium connection and the specified electron-donating compound (c) from 0.1 to 500, more preferably from 1 to 300, in particular from 3 to 100.

As explained above, the solid catalytic component is going to win in addition to the above electron donor Ti, Mg and halogen. In particular, the catalytic component contains compound of titanium, having at least a link Ti-halogen, and the above electron-donating compound on a substrate of the Mg halide. The magnesium halide preferably represents MgCl2in the active form, which is widely known from the patent literature as a carrier for catalysts of the Ziegler-Natta. U.S. patents 4298718 and 4495338 were first described the use of these compounds in catalysis Ziegler-Natta. Of these patents, it is known that dihalogenide magnesium in the active form used as the carrier or joint media components of catalysts for the polymerization of olefins, characterized by x-ray spectra in which the most intense diffraction line which appears in the spectrum of active halide, decreases in intensity and is replaced by a line of halogen, the maximum intensity of which is shifted towards smaller angles relative to the more intense lines.

The preferred titanium compounds are TiCl4and TiCl3; moreover, you can also use Ti-galogenangidridy formula Ti(OR)n-yXy, where n denotes the valence of titanium, y is a number from 1 to n, X is halogen, and R is a hydrocarbon radical having from 1 to 10 carbon atoms.

Getting the firmness of the Dogo catalytic component can be done in several ways, well known and described in the field.

According to a preferred method of the solid catalytic component can be obtained by the interaction of the titanium compounds of formula Ti(OR)n-yXy, where n is the valence of titanium and y is a number from 1 to n, preferably TiCl4with magnesium chloride, a derivative of the adduct of formula MgCl2-d, where p equals the number between 0.1 and 6, preferably from 2 to 3.5, and R is a hydrocarbon radical having 1-18 carbon atoms. The adduct can be obtained in the form of spherical particles in a suitable way, by mixing alcohol and magnesium chloride in the presence of an inert hydrocarbon immiscible with the adduct, operating under conditions of agitation at a temperature of melting 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 adducts with spherical particles obtained according to this method, described in U.S. patent 4399054 and 4469648. Thus obtained adduct can directly be used to interact with the connection Ti or you can expose it to a thermally regulated dealcoholization (80-130°C), and thus, adduct, in which the number of moles of alcohol are typically less than 3, preferably between 0.1 and 2.5. Interaction with connection Ti can be suspending the adduct (dealcoholizing or the such) in cold TiCl 4(usually 0°C); the mixture is heated up to 80-130°C and kept at this temperature for 0.5-2 hours Processing TiCl4you can run one or more times. Electron-donating compound (compounds) can be added during processing TiCl4.

Regardless of the method used to obtain the final number of electron-donor compounds (compounds) is preferably such that the molar ratio relative to the MgCl2is from 0.01 to 1, more preferably from 0.05 to 0.5.

These components of the catalysts and the catalysts described in WO 00/63261 and WO 01/57099.

You can conduct a preliminary interaction of the catalyst with small quantities of olefin (pre-polymerization), maintaining the catalyst in suspension in a hydrocarbon solvent and carrying out the polymerization at a temperature in the range from ambient temperature up to 60°C, and thus, the amount of polymer is from 0.5 to 3 times the weight of the catalyst. The process can also take place in liquid monomer, producing in this case, the number of polymer equal to 1000 times the weight of the catalyst.

Using the above catalysts, get the polyolefin composition in the form of spherical particles having an average diameter of about from 250 to 7000 μm, the fluidity of less than 30 s and bulk density (in pressed state) more than the 0.4 g/ml

Stage polymerization can proceed in the liquid phase, gas phase or liquid phase. Preferably carry out the polymerization of the crystalline polymer (a) in the liquid monomer (for example, using as a diluent liquid propylene), whereas stage copolymerization of elastomeric copolymer (b) and polyethylene (c) is carried out in the gas phase. Alternatively, all three stages of polymerization can be conducted in the gas phase.

The reaction temperature is at the stage of polymerization to obtain a crystalline polymer (a) and upon receiving the elastomeric copolymer (b) and polyethylene (c) may be the same or different and is preferably from 40 to 100°C; more preferably, if the reaction temperature is from 50 to 80°C upon receipt of the polymer (a) and from 70 to 100°C to produce the polymer components (b) and (c).

The pressure at the stage of polymerization to obtain the polymer (a), if it is carried out in liquid monomer, is the pressure, which competes with the vapor pressure of the liquid propylene at the used operating temperature, and it is possible to adjust the vapor pressure of the small quantity of inert diluent used to feed the catalytic mixture, the pressure in the optional monomers and hydrogen, used as a molecular regulator is assy. The pressure of polymerization is preferably from 33 to 43 bar, if it is conducted in the liquid phase, and from 5 to 30 bar, if it is conducted in the gas phase. As for the two stages, the duration of treatment depends on the desired ratio between the polymer (a), (b) and (c) and usually ranges from 15 min to 8 hours, you Can use conventional molecular weight regulators, known in this field, such as transfer agents circuit (for example, hydrogen or ZnEt2).

You can add conventional additives, fillers and pigments commonly used in olefin polymers, such as initiators of crystallization, the expansion of the oil, mineral fillers and other organic and inorganic pigments. In particular, the addition of inorganic fillers, for example talc, causes improvement in certain mechanical properties such as bending modulus and HDT. Talc can also cause crystallization.

The crystallization initiators are preferably added to the compositions of the present invention in quantities of from 0.05 to 2 wt.%, more preferably from 0.1 to 1 wt.% respect to the total mass.

Details are given in the following examples, which are given for illustration and do not limit the present invention.

For definition of characteristics, refer to the detailed description and in the examples, use the following Academy of Sciences of the lytic methods.

Ethylene: the method of IR-spectroscopy.

Fractions, soluble and insoluble in xylene at 25°C: 2.5 g of polymer are dissolved in 250 ml of xylene at 135°C under stirring. After 20 minutes the solution is allowed to cool to 25°C. while continuing the stirring, and then left for 30 min for sedimentation. The precipitate is filtered through filter paper, the solution is evaporated in a stream of nitrogen and the residue is dried in vacuum at 80°C until reaching constant weight. Thus, calculate the percentage weight of the polymer, soluble and insoluble at room temperature (25°C).

Characteristic viscosity [η]: measured in tetrahydronaphthalene at 135°C.

The molecular mass (Mn, Mw, Mz): measured by means of gel chromatography (GPC) in 1,2,4-trichlorobenzene.

The definition of the content of the isotactic pentad: 50 mg of each fraction insoluble in xylene, dissolved in 0.5 ml of C2D2Cl4. Spectra13C receive NMR spectrometer Bruker DPX-400 (100,61 MHz, 90° pulse, the delay between pulses 12). For each spectrum, produce about 3000 savings; the peak of the mmmm pentad (at 21.8 ppm) used as a comparison. The microstructure perform as described in the literature (Polymer, 1984, 25, 1640, Inoue Y., etc. and Polymer, 1994, 35, 339, R. Chujo, and others).

Index polydispersity: determination of molecular mass distribution of the polymer. For measuring the population values PI determine the division of the modules when the value of the loss modulus, for example, 500 PA at 200°C using a rheometer with parallel plates, model RMS-800 from Rheometrics (USA), operating at a frequency of generation, which increases from 0.01 rad/s to 100 rad/S. the magnitude of the separation modules can be found in PI using the following equation:

PI=54,6×(separation modules)-1,76,

in which separation modules (MS) is defined as:

MS=(frequency at G'=500 PA)/(frequency at G"=500 PA)

where G' denotes the storage modulus and G" denotes the loss modulus.

The rate of melt flow: determined according to ISO method 1133 (230°C and 2.16 kg).

Bending modulus: determined according to ISO method 178.

Impact strength Izod: determined according to ISO method 180/1A.

Energy gap: determine according to internal method MA 17324. Use the same samples and the method of research to determine the junction temperature ductile/brittle (described herein below), but in this case, determine the energy required to break the sample at -20°C.

Resistance to discoloration under load: resistance to discoloration determine, producing stroke of the plunger having a small disks with a predefined weight, obtained from a subject to study polymer. You need to get the discoloration if the height (h) from the minimum to the maximum allowed by the system, and fixed the th width (diameter) obestsvechivaya area.

Examples 1-3

The plant employed continuously by the method of gas-liquid mixed polymerization, exercise cycles under the conditions specified in table 1.

The polymerization is carried out in the presence of catalytic systems in the three series-connected reactors equipped with devices to transfer the product from one reactor to another, directly behind him next.

Preparation of solid catalyst component

In chetyrehosnuju a round bottom flask of 500 ml, purged with nitrogen, injected with 250 ml of TiCl4at 0°C. While stirring, 10.0 g of microspheric MgCl2·1,9 C2H5OH (obtained according to the method described in example 2 of U.S. patent 4399054, but operating at 3,000 rpm instead of 10000 rpm) and 9.1 mmol diethyl-2,3-(aminobutiramida)succinate. Raise the temperature to 100°C and maintained for 120 minutes Then stop stirring, allow to precipitate a solid product and pumped supernatant liquid. Then add 250 ml of fresh TiCl4. The interaction of the mixture is carried out at 120°C for 60 min, then pumped supernatant liquid. The solid is washed six times with anhydrous hexane (6×100 ml) at 60°C.

Catalytic system and the preliminary polymerization

Interact the above-described solid catalyst component is aluminization (TEAL) and dicyclopentadienyliron (DCPMS) as an external electron-donor component at 12°C for 24 minutes The mass ratio between the TEAL and the solid catalytic component and the mass ratio between TEAL and DCPMS shown in table 1. Then carry out a preliminary polymerization catalyst system, keeping it in suspension in liquid propylene at 20°C for about 5 min before introducing it into the first polymerization reactor.

Polymerization

Curing cycle is carried out in continuous mode in the three series-connected reactors equipped with devices to transfer the product from one reactor to another, directly behind him next. The first reactor is a liquid phase reactor, and the second and third reactors are reactors operating in a fluidized bed gas phase. The polymer (a) receive in the first reactor, whereas the polymers (b) and (c) receive the second and third reactors, respectively. The temperature and pressure constant support during the interaction. As the molecular weight regulator used hydrogen. The gas phase (propylene, ethylene and hydrogen) are constantly analyzed by gas chromatography. At the end of the cycle is unloaded powder and dried under a stream of nitrogen. Then served polymer particles by extrusion, where they are mixed with 8500 mind talc, 1500 mlnd Irganox B 215 (obtained from 1 part of Irganox 1010 and 2 parts of Irgafos 168) and 500 mln of Ca stearate, getting the comp is the position with nuclei of crystals. The Irganox 1010 is pentaerythritoltetranitrate 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoate, despite the fact that Irgafos 168 is a Tris(2,4-di-tert-butylphenyl)FOSFA, both from Ciba-Geigy. Polymer particles ekstragiruyut in nitrogen atmosphere in a twin-screw extruder with a rotation speed of 250 rpm and a melting temperature of 200-250°C.

Example 4

Repeat example 1 except that the catalytic component replaces the catalytic component containing diisobutylphthalate instead diethyl-2,3-(aminobutiramida)succinate, and get crystalline homopolymer in two stages. Both stage is carried out in liquid-phase reactor.

Comparative example 1 (1c)

Repeat example 4, except that not carry out the polymerization in the second liquid-phase reactor, do not carry out the polymerization of ethylene in crystalline polyethylene, and receive an elastomeric ethylene-propylene copolymer rubber in both the first and second gas-phase reactor.

Comparative example 2 (2c)

Repeat example 4, except that not carry out the polymerization of ethylene in crystalline polyethylene, and receive an elastomeric ethylene-propylene copolymer rubber in both the first and second gas-phase reactor.

In table 1-4 summarizes the polymerization conditions, the distinguishing characteristics of the compositions.

Table 1
The polymerization process
Example12341c2c
Mass. soothes. TEAL/TV. catalytic. component916913109
Mass. soothes. TEAL/DCPMS4562,752,3
1st zhidkovan. reactor
Temperature. polymerization °C696870677067
Pressure, bar3939394139,540
Will continue. processing the weave min595063526232
The mass of the H2, molding7400960069007980670010000
2nd zhidkovan. reactor
Temperature. polymerization °C---67-61
Pressure, bar---41-40
Will continue. processing, min---35-26
The mass of the H2, molding--- 7300-9800
1st gas phase reactor
Temperature. polymerization °C808080858080
Pressure, bar161617151515
Will continue. processing, min332318241513
C2-(C2-+C3-), %0,230,240,270,290,360,23
H2/C2-, %0,0690,0460,0490,0710,0530,055
The 2nd gas phase reactor
Temperature. polymerization °C8385100908080
Pressure, bar1718151220,819
Will continue. processing, min373314222723
C2-(C2-+C3-), %0,980,980,990,990,360,23
H2/C2-, %0,650,6950,2970,40,0500,053
Notes: Mass of H =hydrogen concentration in the liquid monomer; C2-=ethylene; C3-=propylene.

The number of components (a)-(c) in the thus obtained polymer compositions and distinctive features of each component are listed in table 2.

Table 2
The study of composition
Example12341c2c
The crystalline propylene homopolymer
The content of homopolymer,
wt.%
61,764,261636870
MFR, g/10 min597171536980
Index polydispersitythe 5.7the 5.7the 5.7 a 4.95the 5.7
The ratio Mw/Mn15,315,315,310,48,910,9
The ratio of Mz/Mw7,37,37,34,24,47,7
The content of the pentad, mole.%98,498,498,498,498,698
The fraction soluble in
xylene, wt.%
2221,92,02,5
The copolymer of propylene-ethylene
The content of the copolymer, wt.%23,323,723 233230
The ethylene content in the EPR,
wt.%
393940404742
Characteristic viscosity [η] of the fraction 13, soluble in xylene, DL/g2,5(1)2,9(1)3,1(1)3,1(1)2,98(2)2,96(2)
The fraction soluble in
xylene, wt.%
25,7(1)25,3(1)25,7(1)25,7(1)-
Polyethylene
The content of polyethylene, wt.%1512,1 161300
The ethylene content in PE,
wt.%
100100100100--
Characteristic viscosity [η], DL/g1,651,67-1,75-
Notes:
EPR: elastomeric ethylene-propylene copolymer rubber;
PE: crystalline polyethylene.
(1)The value measured on the polymer composition obtained in the first and second reactors.
(2)The value measured on the polymer composition obtained in the first, second and third reactors.

The distinguishing characteristics of the final composition and properties of the compositions as a whole are listed in tables 3 and 4, respectively.

Table 3
The final song
Example12 341c2c
The ethylene content,
wt.%
23,822,125,222,315,112,5
Fraction soluble in xylene, wt.%22,821,122,522,228,228,1
Characteristic viscosity [η] of the fraction soluble in xylene, DL/g2,52,93,12,52,982,96
The mass ratio of EPR/PE1,51,91,41,8--

Table 4
Properties of compositions in General
Examples and comparative examples2341c2c
MFR, g/10 min151512,213,914,314,7
Bending modulus, MPa968107511508959881150
Shockat 23°C42,53939to 49.917,213
Izodat 0°C12,111,811,816,711,59,3
Kj/m2at -20°C7,19,19,1 9,29,27,5
Resistanceheight 5 cm6070706090120
discoloration: diameter (cm)height 10 cm8010010090110140
obestsvechivayaheight 20 cm120110110110140150
the field in the fallheight 30 cm130130130120170160
plungerheight 76 cm160160160 150190200

The data in the examples show that the compositions of the present invention demonstrate improved resistance to discoloration, good impact resistance Izod and relatively low stiffness.

1. Polypropylene composition having good resistance to discoloration and impact resistance, contains, wt%:
a) from 50 to less than 70% of a crystalline propylene homopolymer with the amount of the isotactic pentad (mmmm), measured by the method of13C-NMR of fraction insoluble in xylene at 25°C, 97.5 mol.% and the index polydispersity (PI) from 4 to 10, and the index polydispersity (PI) is determined using the following equation:
PI = 54,6× (separation modules)-1,76where separation modules (MS) is defined as
MS=(frequency at G'=500 PA) / (frequency at G"=500 PA),
where G' denotes the storage modulus, and G" denotes the loss modulus and the storage modulus and loss modulus measured at a temperature of 200°C. using a rheometer with parallel plates, operating at a frequency of generation, which increases from 0.01 rad/s to 100 rad/s;
b) 13-28% of an elastomeric copolymer of ethylene and propylene, the copolymer has a number of repeating units, derivatives of ethylene, 30 to 70% and partially soluble in xylene at a temperature of OK is usausa environment, and the polymer fraction soluble in xylene at ambient temperature, has a value of the characteristic viscosity, measured in tetrahydronaphthalene at 135°C, from 2 to 4 DL/g; and
c) 10-22% of polyethylene having a value of the characteristic viscosity, measured in tetrahydronaphthalene at 135°C, from 1 to 3 DL/g;
moreover, in this composition, the component (b), component (C) are in a quantity higher than 30 wt.%.

2. Polypropylene composition according to claim 1, in which the amount of elastomeric copolymer (b) is from 15 to 28 wt.%.

3. Polypropylene composition according to claim 1, in which the amount of the polyethylene ranges from 10 to 20 wt.%.

4. Polypropylene composition according to claim 1, in which the total content of copolymerizing ethylene is at least 17 wt.%.

5. The method of polymerization to obtain a polypropylene composition according to claim 1, comprising at least three successive stages of polymerization, where the crystalline propylene homopolymer (a), the elastomeric polymer (b) and polyethylene (C) receive on separate consecutive stages, operating in each stage except the first stage, in the presence of the formed polymer material and the catalyst used at the preceding stage of polymerization.



 

Same patents:

FIELD: chemistry.

SUBSTANCE: invention relates to methods of producing thermoplastic elastomer compositions, realised through dynamic vulcanisation of a mixture of components of a composition, meant for preparing sealing components, tubing, insulation for components of electric devices, used in aviation, automobile, cable and other industries. The method is realised by loading an ethylene-propylene-diene copolymer and target additives at the first step. Temperature is raised to 120°C and vulcanising agents are added. At temperature of 150°C, thermoplastics are added - polyethylene and polypropylene in amount of 30-50 wt % of their total content and stirring is done at temperature of 190°C. At the second step the remaining amount of thermoplastics is added to the obtained mixture.

EFFECT: obtaining a thermoplastic elastomer composition with improved mechanical, rheological and electrical characteristics.

3 cl, 1 tbl, 3 ex

FIELD: chemistry.

SUBSTANCE: invention relates to production of waterproofing materials in form of profiled objects - cords, meant for sealing joints in unit construction and which provide for waterproofing through fast water regain. The polymer sealing composition contains, wt %: polymer - synthetic ethylene-propylene triple rubber - 23.78-86-80, natural bentonite - 8.68-71.34, sodium carbonate - 0.09-2.38, titanium white - 2.38-4.34 and colouring pigment - 0.09-0.12.

EFFECT: increased degree of water regain, resistance to effect of atmospheric factors, increased frost- and ozone resistance, cohesion strength and elasticity after the material dries.

1 tbl, 2 ex

FIELD: engines and pumps.

SUBSTANCE: invention relates to solid-propellant charges. Proposed charge comprises casing and propellant charge attached thereto by protective-attachment layer. The latter represents a calendered sheet material based on ethylene-propylene and comprising serpentine asbestos as filler, dioctyldecyl adipate as plastifier and n-dinitrosobenzene as adhesive additive. Note here that the surface of aforesaid layer, on boundary of contact with propellant charge, is subjected to modification by thermally-treated 4,4'-diphenyl methane diisocyanate in the amount of 5 to 20 g/m2.

EFFECT: reliable attachment of charge to engine housing that allows charge longer life.

1 dwg, 1 tbl

FIELD: chemistry.

SUBSTANCE: rubber composition consists of, wt %: polypropylene - 3-21, butadiene-nitrile rubber - 22-55, olefin rubber - 2.5 -9.5, modificator, cross-linking agent for rubbers - 1.5-3.5, activator - 0.18-0.3, plasticiser - 3.0-7.5, mineral oil - 8-40. The composition contains polyisocyanate containing not less than two isocyanate groups (0.05-2.3 wt %) as a modificator and polypropylene with 1-6% of grafted maleic anhydride or maleic acid - 6-20 wt %. Plasticiser solubility parametre of is not less than 18 (kJ/m3)1/2.

EFFECT: oil resistance enhancing, decrease of relative residual elongation and melt flow index.

1 tbl, 9 ex

FIELD: metallurgy.

SUBSTANCE: invention relates to metallic-elastomeric compound for manufacturing of products. Compound includes elastomer, allowing molecular weight in the range approximately from 100000 g/mol. up to 300000 g/mol., metal-fibrous material, formed from variety of metallic fibers, each of which allows correlation of length to width, exceeding approximately 1 and binding agent. Metal-fibrous material is mixed with elasticity tester in amount in the range from 50 particles up to 150 parts on 100 particles of elastomer.

EFFECT: products of particular compound are described by additional strength, ability to heat passage, electrical conductance and flexibility.

8 cl, 8 tbl, 13 dwg

FIELD: chemistry.

SUBSTANCE: polyethylene composition is intended for formation with blowing of barrels with 2 discharge holes with volume ranging from 50 to 250 dm3(l). Composition has density within the range from 0.950 to 0.956 g/cm3 at 23°C, value of index of melt flow rate MFR190/21.6 within the range from 1.5 to 3.5 dg/min and multimodal molecular-weight distribution. It includes from 35 to 45 wt % of homopolymer of ethylene A with low molecular weight, from 34 to 44 wt % of copolymer B with high molecular weight, representing copolymer of ethylene and 1-olefin, containing from 4 to 8 carbon atoms, and from 18 to 26 wt % of copolymer of ethylene C with superhigh molecular weight. Copolymer B contains less than 0.1 wt % of comonomer calculating on copolymer B weight, and copolymer C contains comonomers in amount from 0.1 to 0.6 wt % calculating on copolymer C weight.

EFFECT: polyethylene composition possesses increased impact viscosity and has high degree of blowing 180-220%.

9 cl, 1 ex, 1 tbl

FIELD: personal use articles.

SUBSTANCE: invention refers to rubber composition, to forming method of protective items made of this composition, to protective items of complex shape and to protective glove, made of rubber composition by press vulcanisation method. The composition is based on ethylene-propylene-diene caoutchouc mixture skept 40 and butyl rubber bk 1675 taken at equal rate. For fire-resistance qualities the composition contains antimony oxide mixed with chlorinated paraffin 470 and 1100.

EFFECT: produced goods have high mechanical qualities in combination with chemical and fire resistance to it to be used in extreme conditions influenced by aggressive environment, toxic chemical and propellant components.

5 cl, 2 tbl

FIELD: chemistry.

SUBSTANCE: invention refers to making a moulded product for handling clean-room materials, intermediate products or end products, such as a container, a tray and a tool. The moulded product is made of resin compound prepared by mixing in melt cycloolefine polymer (A) 100 weight fractions chosen from the group including bicyclo[2.2.1]-2-heptene and its derivatives, tricyclo [4,3,0,12,5]-3-decene and its derivatives, and tetracyclo[4,4,0,12,5,17,10]-3-dodecene and its derivatives of vitrification temperature within 60 to 200°C, and amorphous or low-crystalline elastic copolymer (B(b1)) 1 to 150 weight fractions. Copolymer (B(b1)) is polymerised from at least two monomers chosen from the group including ethylene and a-olefin with 3 to 20 carbon atoms and vitrification temperature 0°C or lower. The compound contains radical polymerisation initiator 0.001 to 1 weight fractions containing peroxide, and polyfunctional compound (D) 0 to 1 weight fractions. The compound (D) has at least two radical-polymerised functional groups chosen from the group including vinyl group, allylic group, acrylic group and methacrylic group in a molecule.

EFFECT: clean-room moulded product is characterised with good chemical stability, heat resistance and dimensional accuracy, it prevents volatile component release in the surrounding space, has good abrasion resistance and prevents particle formation.

19 cl, 1 tbl, 2 dwg, 12 ex

FIELD: chemistry.

SUBSTANCE: composition contains propylene polymer 60 to 85 % with wide chain-length distribution of polydispersity index 5 to 15 and melt flow rate speed 40 to 75 g/10 min, specified according to ASTM-D 1238, provision L, at 230°C under load 2.16 kg and partially xylene-soluble polyolefin rubber 15 to 40 % containing ethylene propylene copolymer containing at least ethylene 65 wt % and xylene-insoluble components approximately 25-40 wt % specified at 25°C. Polyolefin composition is characterised with good balance of mechanical properties, particularly improved balance of bending elastic modulus and impact strength even at low temperatures, e.g., at -30°C, and also low heat settings.

EFFECT: specified property ensures high dimensional stability to the products made of polyolefin composition according to the present invention.

5 cl, 2 tbl, 2 ex

FIELD: chemistry.

SUBSTANCE: present invention relates to a polyethylene composition with multimodal molecular weight distribution, which is specially suitable for blow moulding large containers with volume ranging from 10 to 150 dm3 (l). The composition has density which ranges from 0.949 to 0.955 g/cm3 at 23°C and melt flow rate (MFR190/5) from 0.1 to 0,3 dg/min. The composition contains from 38 to 45 wt % homopolymer of ethylene A with low molecular weight, from 30-40 wt %, copolymer B with high molecular weight, obtained from ethylene and another 1-olefin, containing 4 to 8 carbon atoms, and from 18 to 26 wt % copolymer C with ultra-high molecular weight. The composition has Izod impact strength with notch (from ISO) from 30 to 60 kJ/m2 and resistance to bursting under stress (FNCT) from 60 to 110 hours.

EFFECT: large blow moulded objects made from the composition have high mechanical strength.

9 cl, 1 tbl, 1 ex

FIELD: chemistry.

SUBSTANCE: composition is based on secondary polypropylene which contains crushed polypropylene in form of flakes with size of not more than 10 mm, obtained from waste polypropylene objects used in contact with petroleum products and are separators of oil-water emulsion or different oil storage vessel. The composition contains, wt %: said crushed polypropylene - 40-45, low density primary polyethylene - 35-39, inorganic powder filler - 20-21.

EFFECT: wider range of cheap materials based on secondary polypropylene material.

2 cl, 4 ex, 2 tbl

FIELD: chemistry.

SUBSTANCE: invention relates to methods of producing thermoplastic elastomer compositions, realised through dynamic vulcanisation of a mixture of components of a composition, meant for preparing sealing components, tubing, insulation for components of electric devices, used in aviation, automobile, cable and other industries. The method is realised by loading an ethylene-propylene-diene copolymer and target additives at the first step. Temperature is raised to 120°C and vulcanising agents are added. At temperature of 150°C, thermoplastics are added - polyethylene and polypropylene in amount of 30-50 wt % of their total content and stirring is done at temperature of 190°C. At the second step the remaining amount of thermoplastics is added to the obtained mixture.

EFFECT: obtaining a thermoplastic elastomer composition with improved mechanical, rheological and electrical characteristics.

3 cl, 1 tbl, 3 ex

FIELD: chemistry.

SUBSTANCE: invention relates to polyolefin compositions with good balance of hardness and impact-resistance and high elongation rating. A hetero-phase polyolefin composition is described, containing (wt %): (A) from 50 to 80 wt % crystalline propylene polymer with polydispersity index from 5.2 to 10 and isotactic pentad (mmmm) content over 97.5 mol %, determined by 13C-NMR spectroscopy in a fraction which is insoluble in xylene at 25°C; wherein the said polymer is chosen from a propylene homopolymer or propylene copolymer and at least a comonomer, chosen from ethylene and α-olefin with formula H2C=CHR, where R is a linear or branched C2-6-alkyl radical, containing at least 95 % repeating units derived from propylene; (B) from 5 to 20 % of the first elastomeric ethylene copolymer with at least a comonomer chosen from propylene and another α-olefin with formula H2C=CHR, where R is a linear or branched C2-6-alkyl radical; wherein the said first elastomeric copolymer contains from 25 to less than 40% ethylene and is soluble in xylene at room temperature in amount ranging from over 85 wt % to 95 wt %, where characteristic viscosity [η] of the fraction soluble in xylene ranges from 2.5 to 4.5 dl/g; and (C) from 10 to 40% of a second elastomeric ethylene copolymer with at elast a comonomer, chosen from propylene and another α-olefin with formula H2C=CHR, where R is a linear or branched C2-6-alkyl radical; wherein the said second elastomeric copolymer contains 50 to 75% ethylene and is soluble in xylene at room temperature in amount ranging from 50 wt % to 85 wt %, where characteristic viscosity [η] of the fraction which is soluble in xylene ranges from 1.8 to 4.0 dl/g; in which total amount of copolymer (B) and copolymer (C) ranges from 20 to 45 % of the total amount of components (A)-(C), total amount of ethylene with respect to total amount of components (A)-(C) is 23 wt %, and the ratio of ethylene content in the fraction which is insoluble in xylene at room temperature, (C2xif), multiplied by the weight percent content of the fraction which is insoluble in xylene at room temperature, (%XIF), and ethylene content in the fraction which is soluble in xylene at room temperature, (C2xsf), multiplied by weight percent content of the fraction which is soluble in xylene at room temperature (%SXF), i.e. C2xif x % XIF)/(C2xsf x % SXF), satisfies the following relationship (I): (C2xif x % XIF)/(C2xsf x % SXF)>0.01 x + 0.261, where x is total amount of ethylene. Described also is a method of polymerisation of the polyolefin composition described above, involving at least three consecutive steps, where components (A), (B) and (C) are obtained on separate consecutive steps, where operations on each step, except the first step, take place in the presence the polymer formed in the previous step and catalyst used in the previous step.

EFFECT: obtaining polyolefin compositions with high hardness, without reducing impact resistance, especially impact resistance at low temperatures and elastic properties.

2 cl, 3 tbl, 4 ex

FIELD: chemistry.

SUBSTANCE: invention relates to concentrate of additives for polyolefin processing. The concentrate contains polybutylene-1, polypropylene and from 5% to 6% of one or more additives. The concentrates compound a product, which can be added to various polyolefin for adding additives. Colored polypropylene fiber is prepared by mixing polyolefin with concentrate containing pigments with further moulding. The concentrates are used for volume coloring of polyolefines.

EFFECT: precisely, invention simplifies coloring stage during extrusion of polypropylene fibers.

8 cl, 2 tbl, 1 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to polymer compositions, in particular to polypropylene compositions. Composition contains isotactic polypropylene or its copoloymers with ethylene and polypropylene, modified with synthetic caoutchouc of Armlen brand, with their weight ratio equal 1-10:1. Products from claimed composition have higher physico-mechanical properties in wide range of temperature from (-)120°C to (+)170°C, which allows using them in conditions of Far North and permafrost.

EFFECT: increasing physico-mechanical properties of products obtained by casting under pressure.

2 cl, 3 ex

FIELD: chemistry.

SUBSTANCE: invention concerns obtaining stabilisers applied in stone mastic asphalt concretes designed for road and aerodrome construction. Stabiliser has form of cellulose fibre granules. Cellulose fibre granules include oxidised atactic polypropylene.

EFFECT: stability of mix storage and transportation, enhanced adhesion properties of bitumen or bitumen binding agent with mineral mix components in production of stone mastic asphalt, enhanced water resistance without preliminary modification of bitumen.

FIELD: chemistry.

SUBSTANCE: thermoplastic elastomeric composition contains polypropylene, polyethylene, triple ethylene-propylene-diene copolymer, sulfur, primary and secondary vulcanisation accelerators, stearic acid and zinc oxide. Rubber crumb and bitumen are introduced into composition additionally. Combination of components in definite ratio improves rheological properties of composition and, correspondingly its processability.

EFFECT: high-strength products, of high ozone and atmosphere stability, resistance, can be practically fully utilised after expiry of product life.

5 cl, 2 tbl, 6 ex

FIELD: chemistry.

SUBSTANCE: composition of mother mixture has value of characteristic viscosity [η] of fraction, soluble in xilol at room temperature, equal or higher than 3,5 dl/g and contains 50-90 wt % of crystalline polypropylene and 10-50 wt % of ethylene copolymer and, at least, one C3-C10 α-olefin, which contains from 15 to 50 % of ethylene. Crystalline polypropylene contains two fractions with melt flow rate at 230°C and loading 2.16 kg from 0.1 to 10 g/10min (MFRI) and from 10 to 68 g/min (MFRII), respectively. Ratio MFRI/MFRII is from 5 to 60.

EFFECT: obtaining end polyolefin composition, ready for manufacturing by casting under pressure of large products, which have excellent surface appearance due to reduction of tiger stripes and absence of gels.

7 cl, 2 tbl, 5 ex

FIELD: chemistry.

SUBSTANCE: invention refers to rubber-processing industry, in particular to development of thermoplastic elastomeric rubber materials that can be used for manufacturing of various extrusion profiles and moulded flexible parts for automotive, cable, light industry and construction engineering. Thermoplastic elastomeric material is made of composition including, wt. fraction: rubber - 100, polyolefin - 2-150, vulcanising agent 1-15, vulcanisation activator 3-10, stearic acid - 0.75-2.0, oil - 25-500 and bulk additive - 1-100, modified diene-containing thermoplastic elastomer, such as hydrooxylated, halogenated, hydrogenated or hydrohalogenated dienevinylaromatic thermoplastic elastomer - 5-150, release agent - zinc stearate, calcium stearate or their mixture - 0.1-2.0. As oil additive the material contains paraffine-naphthene oils, as bulk additive is contains powder filler with particle size 100 nanometers to 20 microns, selected from the group: schungite, kaolin, chalk, talcum powder or carbon white, as well as mixed mineral additive with 0.04-4.0 mass % of industrial carbon. Thus as rubber thermoplastic elastomeric material contains ethylene-propylene-diene rubber with propylene chains 27 to 40 mass %, and as the third comonomer is contains ethylidene norbornene or dicyclopentadiene in amount 2-10 mass %, as well as butyl rubber, chlorbutyl rubber, brominated butyl rubber, polyisoprene rubber, butadiene-styrene rubber, or polybutadiene rubber. As polyolefin it contains isotactic polypropylene, polyethylene or their mixture at ratio of polyethylene mixed with isotactic polypropylene in amount of 5-95 mass %.

EFFECT: production of material possessing high technological and physical-mechanical properties, melt processability to products without vulcanisation by moulding under pressure or extrusion, low density, high fullness by oil.

5 cl, 2 tbl

FIELD: chemistry.

SUBSTANCE: invention refers to foam composition for cables and to telecommunications cable containing foam composition. Foam composition of density 85 kg/m3 to 120 kg/m3 is produced by heating up the olefin polymer, mainly, with foaming initiator added to molten state. Molten mixture is extruded under pressure through draw plate using foaming agent containing atmospheric gas, e.g. carbon dioxide, nitrogen or air, and additional foam-blowing agent of boiling point within -65°C to +50°C, selected from hydrofluorocarbons, hydrochlorofluorocarbons or perfluoro compounds. As olefin polymer mixture contains high density polyethylene, average density polyethylene, low density polyethylene, linear low density polyethylene, polypropylene or their combinations. Cable is produced by extruding foam composition to signal-carrying conductor and coating signal-carring conductor embedded in foam material with suitable conducting screen.

EFFECT: produce telecommunication cable of low-loss signal; mixture of foaming agents is ecologically comprehensible, not inflammable and nontoxic and allows for considerable reduction of foam density maintaining number of open pores at comprehensible level.

15 cl, 9 tbl, 16 ex

FIELD: chemistry.

SUBSTANCE: composition contains at least one high-molecular polyethylene and at least one low-molecular polyethylene component. The high-molecular polyethylene component of the composition has molecular weight distribution of approximately 6 to 9, content of short-chain branches less than approximately 2 branches per 1000 carbon atoms of the main chain and Mz - approximately 1100000 or greater. The ratio of weight-average molecular weight of the high-molecular polyethylene component to the weight-average molecular weight of the low-molecular polyethylene component is less than 20. The disclosed composition has density greater than 0.94 g/cm3, resistance to cracking under the influence of the surrounding medium greater than 600 hours and percentage swelling greater than 70%.

EFFECT: improved mechanical strength characteristics, suitable for blow moulding.

22 cl, 1 tbl, 16 ex

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