Polyethylene composition and finished products obtained from it

FIELD: chemistry.

SUBSTANCE: group of inventions relates to polyethylene compositions for films or cast products. Composition has melt fluidity index at 5 kg/190°C (MI5 kg) from 0.25 to 3 g/10 min, Mz higher than 2000000 g/mol and lower than 370000 g/mol and Hostalen index (HI) value from 0.18 to 18. When melt fluidity index at 5 kg/190°C (MI5 kg) is higher than 1.9 g/10 min, Hostalen index (HI) value is higher than 1.

EFFECT: polyethylene composition in accordance with invention, possessing specified molecular-weight distribution and long-chained branched structure, possesses improved technological properties, and obtained films have higher mechanical impact strength with film thickness being 10 mcm than at 20 mcm, in accordance with measurement of dart drop impact (DDI).

9 cl, 4 tbl, 8 ex, 1 dwg

 

The present group of inventions relates to new plastic compositions for molding and made of them films and other molded products.

Adaptability is obtained by using a Ziegler catalyst (Ziegler) polyethylene products, due to their complex distribution of comonomers and molecular weight distribution, and potential production in the form of mixtures in multimode reactors in various stages of the reactions, is a task in which there is always a need of improvement. It is known that padmakshi of Ziegler polymer having an extremely high molecular weight, exceeding 500000 g/mol, and having long chain branching (LCB), have excellent processability of the whole polymer products; they are often called by the term "high molecular weight tail" because they constitute a relatively small quantitative portion of the total polymer and have a minor impact on weighted mean molecular mass Mn. The LCB structure, its degree of branching, and the distribution of the chain length substantially affect the technological properties, affecting the degree and strength of the plexus between the macromolecular chains. It is a known property of products Ziegler (Malpass and others, 1989, U.S. patent US 4851489).

However, the mere introduction of more CB products in Ziegler different ways, including, for example, the introduction of radical initiators in the extrusion process or electron beam treatment, does not create the desired effects and/or unreliable. There is too great a variety of factors and features to consider. The object of the present invention is to develop improved products Ziegler, which, in direct result of the catalytic process, exhibits improved technological properties.

This was the task of a polyethylene composition according to the present invention and a direct catalytic process for their preparation using a Ziegler catalyst. Developed polyethylene composition having an index of fluidity of the melt at 5 kg/190 ºC according to ISO 1133:2005 (abbreviated MI5 kg) from 0.25 to 3 g/10 min, preferably from 0.3 to 2 g/10 min, preferably from 0.31 to 1 g/10 min and/or the index value of Hostalen technology, hereinafter referred to as the index of Hostalen or abbreviated HI, from 0.18 to 18 with the proviso that for MI5 kgin excess of 1.9 g/10 min, the value of HI is greater than 1.

The compositions according to the present invention typically and preferably have a density of 0.92 to 0.97 g/cm3preferably from 0,935 to 0,965 g/cm3.

In one preferred embodiment of the invention, the polyethylene composition has a value of H from 1 to 17, preferably from 1.1 to 16.5, most preferably from 2 to 16. This range of values is most suitable for film products, including film products obtained by extrusion blown film and film products, cast from solution, and most suitable for films obtained by extrusion-blow moulding.

In another preferred embodiment of the invention, the polyethylene composition has a HI from 0.22 to 10, preferably from 1.1 to 10. This range of values is the most appropriate for certain types of films and/or hollow, obtained by molding blown film products, including, for example, cans, storage tanks, bottles or similar articles.

In another preferred embodiment of the invention, alone or in combination with the above, the value of MI5 kgranges from 0.3 to 2 g/10 min, preferably from 0.33 to 1 g/10 min.

The value of HI according to the present invention is calculated by the following equation:

HLCBI=(Mz/Mw)•(1/(gMz)•(eh0.1-1-0,99)

where:

Mzand Mwrepresent the third and second (or weighted mean) moment of the molecular weight distribution, determined by the method of gel permeation chromatography coupled with multiangle laser light scattering (GPC-MALLS). A more detailed description of this method m�can be found in the experimental part. For recording data and calculating values of Mzand Mwfrom experimentally obtained distribution curve used commercially available GPC software from the company hs GmbH, Germany, 55437, Chief Hilbesheim, Hauptstrasse, 36).

The value of gMzis a fanout value of molecular mass M=Mz. The branching ratio is determined for each-eluted fraction of the polymer as the ratio of the mean square radius of gyration <Rg2>Mthe measured polymer and mean square radius of gyration standard linear polyethylene <Rg2>linear

gM=<Rg2>M/<Rg2>linear

The value of eh is a strain hardening of the polymer, for the purposes of this patent at a speed of uniaxial tension 0.1 s-1(eh has a subscript 0.1 s-1) and the test temperature T=150ºC. Deformation or mechanical hardening in uniaxial tension is the ratio of the maximum deformation of the melt viscosity measured at a certain speed stretching ηE,maxand linear response at the same time ηs. Accordingly, the eh is defined as the ratio of:

eh=ηE,maxs

The value of ηsin the absence of the observation�already listed plateau after a certain tension can be defined as the maximum value of the viscosity of the polymer, measured using 10-50 seconds after the start of the strains or sprains L sample ln(L(t)/L(0))≥3 (on the basis of determination of deformation on the enemy (Hencky)).

Linear viscoelastic response ηscalculated according to the linear rheological data G and G at the same temperature multimodal models Maxwell (Maxwell), computing the transient shear viscosity and multiplying it by 3 (the ratio of crotona (Trouton)). The present method and the determination of deformation (mechanical) hardening described Mackosko in C. W. rheology is the book Principles, Measurements and Applications (Rheology principles, measurements and applications, Wiley-VCH, new York, 1994

Deformation flow or rheological properties of polymer melts is of paramount importance to technological operations, including obtaining films, blown film, blow moulding and high temperature molding. Mechanical or strain hardening eh creates a so-called "self-healing effect", which supports a homogeneous deformation of the melt. Thus, polymers exhibiting strain hardening deformation in the course of improve produce films and bottles or other moulded products in terms of homogeneous distribution across the wall thickness. On the other hand, mechanical or strain hardening eh also depends on the mol�'s plastic properties of the composition, unsatisfactory measured as an alternative parameters that reflect the high molecular weight fractions, including Mzor the degree of long chain branching, which reflects the fanout for the high molecular weight tail of Mz. Traditionally, the experts were of the opinion that eh has a positive correlation and is determined by the value of Mzand, ultimately, gMz.

Preferably, the polyethylene composition according to the present invention has a value of gMzmore than 0.26, preferably more than 0.28, most preferably more than 0,31. Preferably, in combination with the above-described preferred embodiments for the implementation of gMzthe value of gMzis less than or equal to 0.45, and preferably is less than or equal to 0.40, and preferably, in combination with the above-described preferred embodiments of implementation, always the value of strain hardening eh exceed 1.2-1the eh value is preferably at least 1.2 sof -1preferably at least 1.4 with-1or exceeds this level.

Polyethylene composition according to the present invention preferably has Mzto 3700000 g/mol, preferably up to 3400000 g/mol and most preferably up to 3200000. On�glacial preferred implementation option is particularly preferred in combination with the above preferred values of g Mzin particular, with gMz>0,31, and the preferred and particularly preferably in combination with the value of eh>1.4 with-1. This further shows that the reduction value of Mzand a lesser degree of long chain branching may coincide with increasing deformation viscosity and therefore processability.

Polyethylene or the polyethylene composition according to the present invention is preferably produced by polymerization of ethylene, optionally in the presence and with the addition of at least one additional comonomer, using at least one Ziegler catalyst. This comonomer as a rule, is a 1-olefin, preferably 1-olefin (C4-C12including 1-butene, 1-n-octene, 1-n-hexene. Preferably the polymerization is carried out in a reactor cascade system at temperatures from 20 to 120ºC, at a pressure in the range from 2 to 60 bar (0,6-6 MPa) and in the presence of a Ziegler catalyst, as described above, which comprises conducting polymerization in at least two stages, wherein the molecular weight polyethylene at this stage reactor regulate the dosing of hydrogen in the polymerization process. Most preferably, according to the present invention, carrying out the polymerization in three sequential or cascade reactor stage, today product, consisting of three fractions in terms of molecular weight distribution. This composition consists of three fractions: the first low molecular weight (A), the second high molecular weight (B) and a third of UHMW (C), and the peak molecular weight Mpx(x=A, B or C) of the said first, second and third molecular-mass fractions are in the ratio MpA<MpB<Mpc. Fractions A, B and C preferably correspond to the products of the first, second and third reactor stages, respectively.

An unexpected result of the implementation of the present invention is that not only the presence of high molecular weight tail, having a molecular mass Mz>500000 g/mol, preferably having a molecular mass Mz>1000000 g/mol, most preferably having a molecular mass Mz>2000000 g/mol, the product Ziegler defines technological properties (which are directly evaluate different tests for different applications, including, for example, the stability of bubbles for blowing films or the viscosity at low shear in the General case), besides the fact that it is related to mechanical properties of impact resistance, required. Without the intention to follow theory, additional information about the fine structure of the polymer provides the deformation uproc�ions in addition to the traditional factors of branching LCB or similar systems, indexes, and all of these properties can be controlled success and, surprisingly, independently from each other. Thus, the developed new plastic compositions having a new, unprecedented properties. You can, for example, to obtain a film having higher mechanical resistance at a film thickness of 10 μm than 20 microns, according to the measurement of impact resistance when the falling load (DDI).

Preferably, the Ziegler catalyst is a wealthy Ziegler catalyst, in particular when use of cascade reactor system, and a new catalyst is not loaded into the system when the reactor one stage to the next stage reactor. According to the present invention, suitable damage tolerant catalyst substantially retains its specific catalytic activity for a long period of time, for example, from 4 to 8 hours, and is sensitive to hydrogen, which allows you to adjust the molecular weight distribution of the polymer at different reactor stages. Specific examples of catalysts that is suitable for this method are a Ziegler listed in the European patents EP 532551, EP 068257 and EP 401776. In these documents described the reaction of alkoxides of magnesium compounds comprising transition metal, SEL�from this group, consisting of Ti, Zr or V (d), and additional ORGANOMETALLIC compound, wherein the said metal is selected from main groups I, II or III of the periodic table. In addition, as is well known in the art, Socialisticheskaya alumoorganic compound preferably used to enhance and preserve the activity of the Ziegler catalyst in the polymerization process; these socializaton and their use is described in European patent EP 257 068. Preferably socialization according to the present invention is trialkylamine in which the alkyl is an alkyl (C1-C10preferably it is an alkyl (C2-C6that may be branched or linear, most preferably it is triethylaluminium or Tripropylamine. Furthermore, the use of alumoorganic of the co-catalyst is discussed and explained in the U.S. patent US 4851489. When to use the reactor cascade method, preferably used intermediate pressure relief, for example, through an evaporation tank, to change the partial pressure of hydrogen, and not necessarily or adequately partial pressure of ethylene at the beginning of a new stage reactor, which requires the difference between the value of Mw�aliminosa product values from the previous stage reactor.

The method of producing a polyethylene composition according to the present invention represents yet another object of the present invention; the method comprises the polymerization of ethylene and optionally at least comonomer as described above, on three consecutive reactor stages using at least one of a Ziegler catalyst and preferably in the presence alumoorganic of co-catalyst. The preferred implementation options regarding the implementation of this method is described in detail in other sections of the present description and in the claims.

Polyethylene composition may further comprise conventional additives, including stabilizers, ultraviolet radiation absorbers, absorbers radicals, fillers, processing AIDS, pigments, plasticizers, and similar substances, the number of which equals or exceeds 10%, preferably equals or does not exceed 5% of the total weight of the composition.

Experimental part

Analytical methods

a. Rheology stretching

Measurements were performed using romatically device with parallel plates Physica MCR 301 from the company AntonPaar GmbH (Graz, Austria), equipped rheological stretching device Sentmanant Elongational rheology is (SER). The measurements were carried out at 150ºC, after in�of derivare for 5 minutes at the temperature of measurement. The measurements were repeated for different samples of each material at speeds of stretching in the range from 0.01 s-1up to 10-1as a rule , when 0,01, 0,05, 0,1, 0,5, 1, 5, 10 with-1. For each measurement the viscosity of the melt under uniaxial tension were recorded as a function of time.

The investigated samples were prepared as follows: 2.2 g of material was weighed and used to fill the molding plate having dimensions of 70×40×1 mm Plate was placed in a press and heated to 200 ºC for 1 min at a pressure of 20-30 bar (2-3 MPa). After reaching a temperature of 200 ºC, the sample was compressed at a pressure of 100 bar (10 MPa) for 4 min After the time of compression, the material is cooled to room temperature, the plate was removed from the mold and out of the compressed polymer plates with a thickness of 1 mm was cut out of a rectangular film having the dimensions 12×11×1 mm, which were used as samples for measurement of strain hardening.

b.1. Helpanimals chromatography to determine the parameters of the molecular weight distribution

Determination of molecular mass Mn, Mw(and, as appropriate, peak molecular weight Mp) was carried out using the method of high-temperature gel permeation chromatography as described in DIN 55672-1:1995-02 (released in February 1995). Deviations according to DIN standard was� as follows: the solvent is 1,2,4-trichlorobenzene (TCB), the temperature of the device and solutions 145ºC and, as a concentration detector, infrared detector IR-4 from the firm PolymerChar (city of Paterna, Valencia 46980, Spain), suitable for use TCB. Used chromatograph WATERS Alliance 2000, equipped consistently established forcelocal SHODEX UT-G and the separation columns SHODEX UT 806 M (3x) and SHODEX UT 807. The solvent was distilled under vacuum and stored in a nitrogen atmosphere with a stabilizing additive 0.025 wt.% 2,6-di-tert-butyl-4-METHYLPHENOL. Used a flow rate of 1 ml/min, injection volume of 400 μl and the concentration of the polymer in the range from 0.008 to 0.05 wt.%. The molecular weight calibration was performed using standard samples of monodisperse polystyrene (PS) from the firm Polymer Laboratories (now Varian, Inc., Essex road, Church Stretton, Shropshire, SY6 6AX, UK) in the range from 580 g/mol to 11600000 g/mol, and optionally hexadecan. A calibration curve was then converted to polyethylene (PE), using the universal calibration method (H. Benoit, P. Rempp & Z. Grubisic, J. Polymer Sci., Phys. Ed., 1967, vol. 5, p. 753). Used the parameters of the equation Mark-Houwink (Mark-Houwink) for PS (kPS=0,000121 DL/g, αPS=0,706) and for PE kPE=0,000406 DL/g, αPE=0,725), valid in TCB at 135ºC. Data recording, calibration and calculation was carried out using the software NTGPC_Control_V6.02.03 and NTGPC_V6.4.24 from the company hs GmbH (Germany, 55437, Ober-X�albersheim, Hauptstrasse, 36), respectively.

Measurements by the method of gel permeation chromatography (GPC) with multiangle laser light scattering (MALLS) to determine Mzcarried out using the device of the PL-GPC C210 for high temperature gel permeation chromatography polyethylene in the following conditions: the column with the copolymer of styrene and divinylbenzene, the solvent is 1,2,4-trichlorobenzene (TCB), flow rate 0.6 ml/min, the temperature of 135ºC, detector type MALLS, as described in more detail in section b.2.

b.2. Analysis by GPC-MALLS to determine the fanout of g(Mz)

Experimentally determine the fanout of g, which allows the detection of long-chain branching in the molecular mass Mz, was measured by the method of gel permeation chromatography (GPC) coupled with multiangle laser light scattering (MALLS), as described as follows.

The parameter g represents the ratio of the mean square radius of gyration of the measured sample and a linear polymer having the same molecular weight. It is a measure of the presence of long chain branching (LCB), as shown by his theoretical conclusions Zimm (Zimm) and Stockmayer (Stockmeyer) (Zimm., J. Chem. Phys., 1949, vol. 17, pp. 1301-1314), although there is some disagreement between the experimentally measured branching ratio g (sometimes from�of ice write g') and theoretically derived, as described Graessley, W. (Acc. Chem. Res., 1977, pp. 332-339). In this context, the fanout of g(Mz) is an experimentally predetermined amount.

Linear molecules show the value of the coefficient g is equal to 1, while values less than 1 on theory indicate the presence of LCB. The value of g was calculated as a function of molecular mass M by the equation:

g(M)=<Rg2>the sample, M/<Rg2>linear standard, M,

where <Rg2>Mrepresents the root mean square radius of gyration for a fraction having a molecular weight M. the Baseline linear standard is calculated on the basis of theoretical values according to the equation Zimma-Stockmayer (Zimm-Stockmeyer) (Zimm., J. Chem. Phys., 1949, vol. 17, pp. 1301-1314) for an ideal linear polymer. The radius of gyration (the size of the polymer in each fraction emerging from helpanimals chromatograph) was measured using a laser (16-corner green laser Wyatt company): for each faction-eluted from the chromatograph, as described above, was determined by the molecular weight M and the fanout of g to determine g at a certain M.

Used high temperature alprostadil chromatograph type 210 from the firm Polymer Laboratories (now Varian, Inc., Essex road, Church Stretton, Shropshire, SY6 6AX, UK) c solution�Telem 1,2,4-trichlorobenzene at 135ºC and at a flow rate of 0.6 ml/min, using three columns Shodex UT 806 and one column UT 807. Solutions of polyethylene (PE) with concentrations from 1 to 5 mg/10 ml, depending on the samples prepared at 150ºC for 2 to 4 hours prior to transfer in injection ampoules SEC, mounted on a rotary charging device and heated to 135°C. the Concentration of the polymer was determined using an infrared detector IR4 company PolymerChar IR4, as shown in section b above.1, and stray light was measured using a multi-detector MALLS models Wyatt Dawn EOS from the firm Wyatt Technology (Santa Barbara, California, USA). Used the laser source with a capacity of 120 mW and a wavelength of 658 nm. The specific refractive index was 0,104 ml/g. Evaluation of data was performed using the software ASTRA 4.7.3 and CORONA from 1.4 Wyatt company (see above). The absolute values of molecular mass M and radius of gyration <Rg2> was determined by extrapolation type Debye (Debye) - eluted for each volume using the above software. The ratio g(M) at a given molecular weight M was then calculated based on the radius of gyration of the test sample and the linear radius of the standard sample having the same molecular weight. In this context, the fanout of g(Mzmeans the value of g, defined for M=Mz.

c. The impact resistance test

Test UDA�prochnosti when the falling load (DDI) was performed according to the method A American standard test method ASTM D 1709: 2004 on films, having a thickness of 20 μm or 10 μm, which is described separately with the corresponding data set.

d. Measurement of the complex viscosity

Dynamic oscillatory shear deformation and her response was applied to the polymer in the rheometer with parallel plates Anton-Paar MCR 300 from the company Anton Paar GmbH (Graz, Austria) to determine the rheology of shear, i.e. the measured complex viscosity η* at a given frequency ω. The first sample (in the form of granules or powder) were prepared for measurement as follows: 2.2 g of material was weighed and used to fill the molding plate having dimensions of 70×40×1 mm Plate was placed in a press and heated to 200 ºC for 1 min at a pressure of 20-30 bar (2-3 MPa). After reaching a temperature of 200 ºC, the sample was compressed at a pressure of 100 bar (10 MPa) for 4 min After the time of compression, the material is cooled to room temperature and removed the plate from the mold. Pressed plates were subjected to visual quality control to detect possible cracks, impurities or inhomogeneities. Disks with a diameter of 25 mm and a thickness of 0.8-1 mm were cut from molded sheets, cut them out and put them into the rheometer for measurement by dynamic mechanical analysis (or frequency sweep). Measurement of elastic modulus (G') and viscosity (G") and complex viscosity η* as a function of the frequency ω was performed using the specified rotate�steering rheometer with adjustable voltage Anton Paar MCR300. This device has a two-plane geometry, i.e. includes two parallel disk of radius 24,975 mm Sample in the form of a disk having a thickness of about 1 mm and 25 mm in diameter, prepared as described above were loaded and heated to a temperature measurement (standard temperature for PE is 190ºC). The molten sample was maintained at the test temperature for 5 min to obtain a homogeneous melt. Then began a frequency sweep using the device for registering the results and 628 from 0.01 rad/s on a logarithmic scale.

Applied periodic deformation in the linear interval with an amplitude of deformation of 0.05 (or 5%). Points chosen from the interval of frequencies on a logarithmic scale, descending from high to low frequencies. A frequency sweep was performed in the interval from 628,3 rad/s (or ~100 Hz) to 8.55 rad/s and in the very small range of frequencies from 4,631 rad/s to 0.01 rad/s (or 0,00159 Hz) with increased speed sampling so that more points were selected for the low frequency range.

The resulting amplitude of the shear strain and the lagging phase with the applied deformation was recorded by means of the device and used to calculate the modules losses and preserve and complex viscosity versus frequency.

e. Other methods of research

Density [g/cm3] determined the dip� according to the method A of DIN EN ISO 1183-1. For the measurements were prepared compressed molded plate of thickness 2 mm, past a certain heat treatment in the pressing conditions (temperature 180ºC, pressure 200 bar (20 MPa), time 8 min) and crystallization in boiling water for 30 minutes.

The content of Al, Fe, Mg and Ti in the catalyst was measured by ICP-OES according to DIN EN ISO 11885.

The coefficients of viscosity was determined directly using a capillary ubbelohde viscometer (Ubbelohde) according to ISO 1191:1975 solutions in decalin at a temperature of 135ºC; the measurement was carried out on a sample of the reaction mixture obtained in Conques first, second or third stage polymerization.

The synthesis of Ziegler catalyst and carrying out the polymerization reaction

As a catalyst of Ziegler received the catalyst according to example 1 of European patent EP 401776. The polymerization was carried out in continuous mode, using a sequence of three cascaded slurry reactors. The Ziegler catalyst was injected only once, in the first reactor. The Ziegler catalyst (suspended in hexane, as indicated) was used with an additional number of triethylaluminum (TEA) as a co-catalyst in a molar ratio of about 1:10, as described below in more detail. Evaporative tanks between reactor stages is possible to adjust the dosage of hydrogen, ethylene and somone�measure individually for each reactor stage.

Example 1

The catalyst concentration: 4,4 mmol/l

The dosage of the catalyst: 4.2 mmol/h

Socialization and its concentration: TEA, 22,8 mmol/l

The content of active Al: 1 mmol/l

Dosage TEA: 61 mmol/h

R1, R2, etc., mean suspension reactors No. 1, 2, etc.

Example 2

The catalyst concentration score of 8.5 mmol/l

The amount of catalyst: 3,6 mmol/h

Socialization and its concentration: TEA, 22,8 mmol/l

The content of active Al: 1.1 mmol/l

Dosage TEA: 61 mmol/h

R1, R2, etc., mean suspension reactors No. 1, 2, etc.

The polymer product was separated from the hexane, dried and pelletized. Films were obtained by extrusion-blow moulding, using a line for blown films Alpine.

Example 3

Molecular weight distribution (drawn line) and the distribution of long-chain branching (LCB/1000 CH2as a function of molecular weight), defined by the radius of gyration method GPC-MALLS, shown in Fig.1 for polymer products according to examples 1 and 2. The results of the test films are presented below in table III.

Table 3
SampleMI5 kgDensity DDI 20 micronsDDI 10 µmThe increase in DDIStrain hardeningStrain hardeningTiAl
Unitg/10 ming/cm3gg% 20 to
10 µm
@0,1 s-1@0.01 s-1g/mol TiCAl/(mmol•h-1cat.)
PR.10,31of 0.9553403605,91,253,01,670,96
PR.20,33of 0.95528034021,41,263,31,330,96

Examples 4-8

Similarly JV�soba polymerization in examples 1 and 2, the following polymer samples 4-8 were obtained according to the present invention, moderately changing process conditions and getting products with different values of Mw, Mz, HI, etc.

In essence, used the method described in example 1, in which the following conditions are changed within the specified limits:

The conditions of polymerization

The ratio of hydrogen to ethylene in the third reactor is 0.3<H2/C2<0,4

The ratio of hydrogen to ethylene in the second reactor: H2/C2=0,08

The comonomer content in the third reactor: 0,8<C4<a 1.3 vol.%

The content of comonomer in the second reactor: 0,5<C4<0,8 vol.%

The concentration trialkylamine (triethylamine): 0,96<CAl<1,2 mmol/l

The partial pressure of ethylene PC2: to 0.65 bar (of 0.065 MPa) in the second reactor and up to 1.25 bar (0,125 MPa) in the third reactor

The properties of the final polymer:

Index the melt flow: MFI5 kg=0,35-0,44 g/10 min

Density: ρ=of 0.955-0,957 g/cm3

Drop durability of the goods at a film thickness of 10 μm; DDI>300 g

Other properties of the polymers obtained in examples 1, 2 and 4-8, subject to the calculations of the parameters HI and melt rheology and compare them with currently available commercial products, mainly from competitors, is presented below in table IV.

1. Plastic �omposite for the production of films and other molded products, having a fluidity index of the melt at 5 kg/190°C (MI5 kg) according to ISO 1133:2005 from 0.25 to 3 g/10 min, Mzmore than 2000000 g/mol and less than 3700000 g/mol and the value of the index Hostalen (HI) from 0.18 to 18 with the proviso that the index of fluidity of the melt at 5 kg/190°C (MI5 kgexceeding 1.9 g/10 min, the value of the index Hostalen (HI) greater than 1, in which the value is defined as HI

where:
Mzis a z-average molecular weight,
Mwrepresents the weighted mean molecular weight,
gMzis a fanout value of molecular mass M=Mz
eh represents the strain hardening of the polymer at a speed of uniaxial tension 0.1 s-1and when the test temperature T=150°C and is defined as the ratio eh=ηE,maxsin which
ηE,maxrepresents the maximum deformation melt viscosity, measured at a given speed of stretching, and
ηsis a linear viscoelastic response.

2. A composition according to claim 1, in which the value of the index the melt flow at 5 kg/190°C (MI5 kg) is from 0.3 to 2 g/10 min and/or the index value Hostalen (HI) is from 0.2 to 10 with the proviso that the index of fluidity of the melt at 5 kg/190°C (MI5 kgexceeding 1.9 g/10 min, the value of the Indus�sa Hostalen (HI) greater than 1.

3. A composition according to claim 1, in which the composition can be obtained catalytically, using at least a Ziegler catalyst.

4. A composition according to claim 1, which composition has a multimodal molecular weight distribution.

5. A composition according to claim 4, in which the composition consists of three factions, including the first low molecular weight (A), the second high molecular weight (b) and a third of UHMW (C), where the peak molecular weight MPxx=A, b or C listed first, second and third molecular-mass fractions are MpA<MpB<MpC.

6. A composition according to claim 5, which can be obtained by polymerization of ethylene in three consecutive reactor stages, using at least one Ziegler catalyst, and optional at this stage reactor in the presence of at least one comonomer which is an α-olefin, preferably α-olefin (C4-C12.

7. Polyethylene composition according to claim 1 for the production of extruded films of thickness less than 1 mm, having a fluidity index of the melt at 5 kg/190°C (MI5 kg) from 0.25 to 1 g/10 min and/or the index value Hostalen (HI) from 1.5 to 18.

8. Polyethylene composition according to claim 7, which made her film has a drop durability of the goods (DDI), determined according to standard method ASTM D1709:2004 method �, which is increased at least 3%, preferably at least 15% with decreasing film thickness from 20 μm to 10 μm, and the value of impact resistance when the falling load (DDI) is at least 300 g or more at a film thickness of 10 μm.

9. Film, preferably a film obtained by extrusion blown film made from the polymer composition according to one of claims.1-8.



 

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FIELD: chemistry.

SUBSTANCE: invention relates to a method of increasing homogeneity of mixtures of polyethylene, intended for manufacturing moulded products, films, tubes, wires and cables. A mixture of polyethylenes contains three fractures (A), (B) and (C) of a homo- or a copolymer of ethylene and at least one comonomer C3-C10 with different molecular weights. The low-molecular fraction A) has the weight-average molecular weight Mw lower than 40 kg/mol, the highly-molecular fraction B) has the molecular weight Mw higher than 250 kg/mol and the fraction C) has the intermediate molecular weight with the weight-average molecular weight Mw from 100 to 200 kg/mol. The mixture of polyethylenes has a single peak of melting as determined by means of differential scanning calorimetry (DSC).

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11 cl, 1 tbl, 3 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a polyethylene moulding composition intended for making pipes, conduits and cables, and a method of producing said composition. The composition has a multimodal molecular-weight distribution, density in the range of 920 to 960 kg/m3, melt flow index MFI190/2 in the range of 0.05 to 10 g/10 min and Shore hardness D, measured according to ASTM D2240-05 (15 s), of at least 56.0. The composition contains at least three ethylene polymer fractions having different molecular weight. Each of the fractions A, B and C is an ethylene homopolymer or a copolymer of ethylene with at least one C3-C10 comonomer.In the composition, one of the fractions A, B and C is an ethylene homopolymer and at least one of the other fractions is an ethylene copolymer with content of said C3-C10 comonomer of 1-15 wt %. Fraction A has weight-average molecular weight Mw in the range of 15 to 40 kg/mol, fraction B - in the range of 70 to 200 kg/mol and fraction C - in the range of 220 to 400 kg/mol.

EFFECT: obtained polyethylene moulding composition has excellent mechanical properties, hardness and wear resistance, and also has high impact resistance and slow crack growth.

13 cl, 6 dwg, 6 tbl

FIELD: chemistry.

SUBSTANCE: method includes stages of mixing an acid-based polymer, a neutralisation agent and a technological additive to obtain a polymer composition. In the process of mixing a level of the acid-based polymer neutralisation constitutes from 25% to 75%. After processing the said polymer composition a polymer fabric, which is granulated into polymer particles, is obtained. The acid-based polymer represents resin with the melt flow index, measured at 190°C under a load of 2.16 kg, from 10 to 60 g/10 min, with the neutralisation agent being selected from the group, consisting of potassium hydroxide, aluminium hydroxide, calcium hydroxide, zinc oxide or their mixtures, salt of metal and fatty acid and a partly or completely neutralised ionomer or their mixtures.

EFFECT: polymer coatings possess a low negative impact on the environment, evaluated by indices of life cycle evaluation.

26 cl, 1 dwg, 10 tbl

FIELD: chemistry.

SUBSTANCE: invention relates to a colourless synthetic binding agent, which is applied in the road-industrial area. The colourless synthetic binding agent contains oil of a vegetable origin, resin of a petroleum origin and a polymer. The quantity of oil of a vegetable origin in the binding agent constitutes 10 wt % or more, and the quantity of the polymer in the binding agent constitutes 15 wt % or less.

EFFECT: colourless synthetic binding agent in accordance with invention possesses good consistency, reduced viscosity, acceptable behaviour at low temperature and acceptable elastic properties.

18 cl, 7 tbl

FIELD: chemistry.

SUBSTANCE: invention relates to hot-melt adhesives. The hot-melt adhesive contains 5-40 wt % of a copolymer based on ethylene and C3-C20 α-olefin, which is obtained by metallocene-catalysed polymerisation, 10-65 wt % of tackifying resin, 0-35 wt % of a plasticiser and 0.01-30 wt % of additives. The additives are selected from stabilisers, adhesion promoters, fillers or pigments, waxes and/or other polymers, wherein the total amounts to 100%. The copolymer is a block copolymer having invariable elastic properties in the range of 0°C to 25°C, measured as a ratio of the storage modulus E′ according to (E'0C-E'25C)/E'25C<1.5.

EFFECT: method improves process properties of the hot-melt adhesive while preserving mechanical properties in the temperature range to 50°C.

18 cl, 5 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a PVC-free floor or wall covering comprising at least one layer of a thermoplastic composition. The composition contains a polymer matrix comprising at least two polymers and at least 100 pts.wt of least one filler per 100 pts.wt of the polymer(s). Said matrix contains 10-40 pts.wt of a polymer with carboxylic acid anhydride groups in amount of 0.5-3.1 wt %, and the other polymer of the matrix is selected from a group comprising EVA, EMA, EBA, EEA, EPM, EPDM, VLDPE, LLDPE, POE, POP and mixtures thereof, and has melt flow index between 0.6 and 3 g/10 min at 190°C and mass of 2.16 kg. The total amount of combined polymers in the composition is 100 pts.wt.

EFFECT: floor or wall covering obtained according to the invention preferably in form of rolls or tiles has improved residual indentation properties and is also suitable for recycling.

14 cl, 7 dwg, 9 tbl

FIELD: chemistry.

SUBSTANCE: coating comprises an adhesive sublayer of a thermoplastic adhesive and a functional layer of a nanostructured composite material based on polyethylene. The composite material of the functional layer has a polyethylene matrix and montmorillonite particles dispersed in the matrix in amount of 0.1-2 wt %.

EFFECT: improved physical and mechanical properties of the coating.

12 cl, 2 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a low-density ethylene polymer with a multimodal comonomer distribution, a method for production thereof and moulded articles, including films, made from said polymer. The multimodal polyethylene has a wide molecular weight distribution MWD in the range from 3 to 8 and contains two polymer components. The first polymer component is 70-95 wt % copolymer of ethylene with at least one C3-C20-α-olefin comonomer, having MWD less than 5, CDBI greater than 60% and high-load melt index (@21.6 kg, 190°C) of 10-100 g/10 min. The second polymer component is 5-30 wt % substantially homopolymeric polyethylene, having MWD greater than 10, CDBI greater than 80% and high-load melt index (@21.6 kg, 190°C) of 0.2-20 g/10 min. Said multimodal polyethylene is obtained in a single reactor using a catalyst system containing at least two catalysts in form of transition metal complexes.

EFFECT: polyethylene disclosed herein has considerably improved resistance to mechanical factors and excellent processing properties, which enable to avoid use of process additives when processing films.

13 cl, 4 dwg, 3 tbl

FIELD: chemistry.

SUBSTANCE: invention relates to method of obtaining cross-linked pipe and to cross-linked pipe, which contains cross-linked polymer composition, containing cross-linked ethylene polymer. method of manufacturing cross-linked pipe includes: (i) polymerisation of ethylene non-obligatorily with one or several comonomers (comonomer) in presence of Ziegler-Natta catalyst with obtaining ethylene polymer, which contains carbon-carbon double bonds; ethylene polymer has: (A) linkability, expressed through the level of gel content, equal, at least, 50 wt %, according to the measurement of disc-shaped sample of cross-linked ethylene polymer (ASTMD 2765-01, Method A, extraction in decalin); or/and (B) content of carbon-carbon double bonds in a number higher than 0.2 carbon-carbon double bond/1000 carbon atoms, according to the measurement by FTIR method; and (ii) obtaining polymer composition, including, at least, 50% wt % of ethylene polymer; (iii) formation of pipe from composition, obtained at stage (ii); (iv) cross-linking pipe, obtained at stage (iii). Ethylene polymer represents ethylene homopolymer or ethylene copolymer with one or several comonomers, and is selected from elastomers (POE), plastomers (OPO) or very low density ethylene copolymers of (VLDPE), which cover the density range from 855 to 909 kg/m3, linear low density ethylene copolymers (LLDPE), which have density in the range from 910 to 930 kg/m3 (ISO 1183), medium density ethylene copolymers (MDPE), which have density in the range from 931 to 945 kg/m3, or high density polyethylenes (HDPE), which are selected from homo- or copolymers of ethylene, and which have density higher than 946 kg/m3. Cross-linked pipe consists of cross-linked polymer composition. Polymer composition before cross-linking includes, at least, 50 wt % of ethylene polymer, where ethylene polymer is obtained by polymerisation of ethylene optionally together with one or several comonomers (comonomer) in presence of Ziegler-Natta catalyst, where ethylene polymer contains carbon-carbon double bonds in a number higher than 0.4 carbon-carbon double bond/1000 carbon atoms, according to the measurement by FTIR method, where ethylene polymer has linkability, expressed through the level of gel content, equal, at least, 50 wt %, according to the measurement for disc-shaped sample of cross-linked ethylene polymer (ASTMD 2765-01, Method A, extraction in decalin) and has MFR2 from 0.01 to 5.0 g/10 min, Mn/Mw from 0.1 to 20.0 g/10 min, and where ethylene polymer represents ethylene homopolymer or ethylene copolymer with one or several copolymers, and is selected from linear low density ethylene copolymers (LLDPE), which have density in the range from 910 to 930 kg/m3 (ISO 1183), medium density ethylene copolymers (MDPE), which have density in the range from 931 to 945 kg/m3, or high density polyethylenes (HDPE), which are selected from ethylene homo- or copolymers and which have density higher than 946 kg/m3.

EFFECT: improvement of material properties.

18 cl, 5 tbl

Sealing mastic // 2542293

FIELD: chemistry.

SUBSTANCE: sealing mastic contains, wt %: chlorobutyl rubber - 3.6-4.2, ether of glycerol tall oil rosin - 1.0-1.5, high pressure polyethylene in the form of a film - 0.3-0.4, zinc borate - 4.0-4.6, magnesium hydroxide - 6.0-7.0, aluminium hydroxide - 22.0-12.0, trichloropropylphosphate - 2.5-3.0, a barite concentrate - 48.0-51.0, chloroparaffin CP-470 - 1.8-2.0, PN-6sh oil - 7.0-8.0.

EFFECT: invention makes it possible to increase soundproofing, vibration damping, adhesion properties and ecological safety.

1 tbl

FIELD: chemistry.

SUBSTANCE: non-drying rubber mixture contains, wt %: butyl-rubber regenerate from waste diaphragm chambers - 17.0-31.0, ether of glycerol tall oil rosin - 0.5-1.0, PN-6sh oil - 20.0-25.0, chalk - 10.0-45.0, high-pressure polyethylene in the form of a film - 0.5-1.3, waste fibres of cotton ginneries - 0.7-1.0, alumosilicate microspheres - 4.0-25.0, talc - 4.0-11.0.

EFFECT: invention makes it possible to increase the damping properties, adhesion to metal and frost resistance of the composition.

1 tbl

FIELD: chemistry.

SUBSTANCE: invention relates to polymer composition for manufacturing sealing and electroinsulating materials for production of connection cable envelope. Composition contains low-pressure polyethylene, lubricant buxol as plasticiser and filling agent representing titanium oxide.

EFFECT: composition is characterised by high thermodynamic compatibility of components, which makes it possible to obtain material with high mechanical characteristics and optimal combination of electro- and hydroinsulating properties.

2 tbl

FIELD: chemistry.

SUBSTANCE: invention relates to polyethylene composition, intended for obtaining slow-burning construction materials of general technical and engineering-technical purpose. Composition contains high-density polyethylene and filling agent with particle size 0.145-0.315 mm in quantity 30-50 wt. p. per 100 wt. p. of polyethylene. Filling agent represents mixture of crushed basalt and crushed basalt wool.

EFFECT: obtained compositions possess increased output of coke residue at 600°C, Vicat softening temperature, temperature of destruction starting, toughness, bending strength, as well as high weight loss during combustion.

1 tbl, 5 ex

FIELD: chemistry.

SUBSTANCE: invention relates to an antifrictional polymer composition based on ultra-high-molecular-weight polyethylene, particularly for making friction bearings in mobile friction assemblies of machines and mechanisms. The composition contains ultra-high-molecular-weight polyethylene and an inorganic modifier, wherein the inorganic modifier used is thermally expanded graphite in amount of 2 wt %.

EFFECT: composition has improved deformation-strength properties, wear resistance and bearing capacity.

1 tbl

FIELD: chemistry.

SUBSTANCE: invention relates to a bimodal polyethylene high-density composition for obtaining products by pressure moulding, in particular caps and plugging means. The composition includes bimodal high-density polyethylene, a composition of an inorganic alpha-nucleating agent, a composition of a friction-reducing agent, representing amide of primary fatty acid, and a composition with one or more additives, selected from antioxidants, acid acceptors, pigments and UV-stabilisers. The application of bimodal polyethylene in a combination with the inorganic alpha-nucleating agent, in particular, with talc and behenamide, as the friction-reducing agent, makes it possible to obtain the moulding composition with an unexpected and synergic impact on crystallisation temperature, and the composition friction coefficient.

EFFECT: composition by the invention demonstrates higher crystallisation temperature and lower friction coefficient.

14 cl, 5 tbl

FIELD: chemistry.

SUBSTANCE: invention deals with ultrahigh molecular weight polyethylene (UHMWPE), modified with nanosized particles of tantalum pentoxide. It is applied for the obtaining polycomposite materials, which can be applied in microelectronics, medicine and other fields. It is obtained by the addition of benzyl alcohol to a UHMWPE benzene solution. The formed reaction mixture is mixed at a rate of 400-500 rev/min in boiling for 5-6 hours. Then, it is filtered, washed with benzene, the solvent is distilled. After that, a benzene solution of tantalum pentachloride is added to the reaction mass in a quantity corresponding to the molar ratio of tantalum pentachloride to benzene alcohol, equal to 1:5-5.3. Then the obtained reaction mass is mixed at the same rate in boiling for 3-4 hours, cooled and the target product is separated by filtering, extraction with chloroform and vacuum distillation of the solvent.

EFFECT: extension of application fields of materials with higher physical-mechanical properties.

3 dwg, 2 tbl, 2 ex

FIELD: process engineering.

SUBSTANCE: invention relates to production of articles of granulated polymer materials. Die is filled with polymer granules over 1 mm in size. Cold moulding and blank forming are performed at pressure not destructing the granule structure with subsequent sintering and cooling down. Note here that granulated material sintering temperature makes 0.58-0.80 of the polymer flow point. At making of articles from the mix of granules of at least two polymers with different flow points the sintering temperature makes 0.58-0.80 of that of easily melted polymer.

EFFECT: lower material and power input.

4 cl, 2 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to a PVC-free floor or wall covering comprising at least one layer of a thermoplastic composition. The composition contains a polymer matrix comprising at least two polymers and at least 100 pts.wt of least one filler per 100 pts.wt of the polymer(s). Said matrix contains 10-40 pts.wt of a polymer with carboxylic acid anhydride groups in amount of 0.5-3.1 wt %, and the other polymer of the matrix is selected from a group comprising EVA, EMA, EBA, EEA, EPM, EPDM, VLDPE, LLDPE, POE, POP and mixtures thereof, and has melt flow index between 0.6 and 3 g/10 min at 190°C and mass of 2.16 kg. The total amount of combined polymers in the composition is 100 pts.wt.

EFFECT: floor or wall covering obtained according to the invention preferably in form of rolls or tiles has improved residual indentation properties and is also suitable for recycling.

14 cl, 7 dwg, 9 tbl

FIELD: chemistry.

SUBSTANCE: fireproof rubber mixture contains isoprene and butadiene rubbers, sulphur, sulphenamide C, zinc oxide, magnesium oxide, paraffin, naphtham-2, diaphene FP, technical carbon, N-nitrosodiphenylamine, chloroparaffin, antimony trioxide, aluminium hydroxide.

EFFECT: improved fire resistance and physical-mechanical properties.

2 tbl

FIELD: process engineering.

SUBSTANCE: set of invention relates to production of water-soluble film from nonwoven web, to film thus made, single-portion article including the bag formed from this film and to process of web article processing with step exploiting said water-soluble film. Production of water-soluble film consists in provision of nonwoven web including multiple filaments with filament-forming material soluble in polar solvent and conversion of nonwoven web into film. Note here that water-soluble film comprises one or more active agents for care of fabrics. Processing of fabric consists in pretreatment of spots on fabric article prior to its washing. Then, flushing solution is made by bringing water-soluble film in contact with water and fabric article in contact with water. Thereafter, fabric article is brought in contact with water-soluble film in drier to dry said article in the presence with water-soluble film in drier.

EFFECT: production of water-soluble film at high forming rates.

46 cl, 4 dwg

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