Polyethylene compositions

FIELD: chemistry.

SUBSTANCE: composition contains a high-molecular weight polyethylene component and a low-molecular weight polyethylene component, and has density of 0.940 g/cm³ or higher and melt strength of 18 cN or higher. The ratio of the weight-average molecular weight of the high-molecular weight component to the weight-average molecular weight of the low-molecular weight component in the composition is greater than 15:1 and less than 28:1, the high- and low-molecular weight polyethylene components being formed by polymerisation in one reactor. The composition is classified as PE 100 material and has the appropriate balance of properties. A tube made from the composition, subjected to an internal strength test, has extrapolated stress of 10 MPa or higher, when the internal strength curve of the tube is extrapolated to 50 or 100 years according to ISO 9080:2003(E).

EFFECT: improved operational characteristics.

22 cl, 3 dwg, 6 tbl

CROSS-REFERENCE TO RELATED APPLICATIONS

The present invention is the benefit of priority application No. 61/135,036, filed July 16, 2008, the disclosure of which is fully incorporated by reference.

The technical FIELD TO WHICH the INVENTION RELATES.

Variants of the present invention generally relate to compositions containing polyethylene, in particular, to a bimodal polyethylene compositions.

PREREQUISITES CREATE ISOBUTENE

Currently, efforts are focused on obtaining polyolefin compositions for pipes, in particular, to obtain polyethylene compositions of high density pipe. The goal is not only resin obtained economically and efficiently, but also getting the pipe with a suitable balance of properties.

Patents US 7037977, US 6090893, US 7193017 and published applications US 2007/027611, US 2004/0157988, and US 2005/0234197 refer to polyethylene resins for pipe. There is a need in the high strength polyethylene compositions exhibiting a suitable balance of properties, including the group of options properties hanged strength melt.

A SUMMARY of IZOBRETENIYA

In accordance with one feature of the invention, it is proposed bimodal polyethylene composition of high density, having a density of 0,940 g/cm³or more, including Vysokomolekulyarnye component and low molecular weight polyethylene component, and: the song belongs to the category of material PE 100, such that in accordance with ISO 1167 pipe, molded from the composition that is subjected to test of inner strength, has extrapolated voltage of 10 MPa or more, when the curve of the inner strength of the pipe is extrapolated to 50 or 100 years, in accordance with ISO 9080:2003(E); and the composition has a melt strength greater than 18 CH.

In one embodiment, high and low molecular weight polyethylene components are formed in a single reactor.

In one embodiment, the melt strength is more than 20 CH. In another embodiment, the melt strength is more than 22 CH.

In one embodiment, the complex viscosity at a frequency of 0.01^-1is more than 3.5*10 PA·C. In another embodiment, the complex viscosity at a frequency of 0.1 s^-1is more than 1.5*10⁵PA·S.

In one embodiment, the total TTD is from 15 to 40.

In one embodiment, the high molecular weight component is present in an amount of from 45 to 60 wt.%, in terms of the total weight of the composition.

In one embodiment, the average molecular weight (Mw) of low molecular weight polyethylene component is from 5000 to 35000.

In one embodiment, the average molecular weight (Mw) of high molecular weight polyethylene component is of 400,000 to 700,000.

In one embodiment, the ratio srednevekov the molecular weight of high molecular weight component to srednevekovoi molecular weight low molecular weight component (Mw _BMM:Mw_HMM) is from 15 to 40: 1. In one embodiment, the IL (I₂₁song is from 4 to 10 g/10 min In one embodiment, high molecular weight polyethylene component has a density 0,945 g/ml or less.

In one embodiment, low molecular weight polyethylene component has a density 0,940 g/ml or more.

In one embodiment, high molecular weight polyethylene component includes polyethylene, which includes comonomer representing butene, hexene, octene, or mixtures thereof, and comonomer is present in the amount of more than 1.0 wt.% relative to the weight of polyethylene.

In one embodiment, low molecular weight polyethylene component includes polyethylene, which includes comonomer representing butene, hexene, octene, or mixtures thereof, and comonomer is present in amount of less than 3.0 wt.% relative to the weight of polyethylene.

In one embodiment, the extrapolated voltage is 10 MPa or more, when extrapolated to 50 or 100 years in accordance with ISO 9080:2003(E).

In one embodiment, high and low molecular weight polyethylene components are formed through the implementation of the gas-phase polymerization.

In one embodiment, high and low molecular weight polyethylene components are formed through the implementation of the suspension polymerization.

In one embodiment, the components of ice obtained by polymerization, carried out in the presence of a bimodal catalyst system that includes a catalyst based on metallocene.

In one embodiment, high and low molecular weight polyethylene components are formed in the polymerization carried out in the presence of a bimodal catalyst system, which includes bis(2-(trimethylaniline)ethyl)lincolniensis.

In one embodiment, high and low molecular weight polyethylene components are formed in the polymerization carried out in the presence of a bimodal catalyst system, which includes bis(2-(pentamethylbenzene)ethyl)lincolniensis.

In one embodiment, the high and low molecular weight polyethylene components are formed in the polymerization carried out in the presence of a bimodal catalyst system, which includes (pentamethylcyclopentadienyl)(n-propylcyclopentanol)zirconiated.

In one embodiment, high and low molecular weight polyethylene components are formed in the polymerization carried out in the presence of a bimodal catalyst system, which includes (tetramethylcyclopentadienyl)(n-propylcyclopentanol)zirconiated or (tetramethylcyclopentadienyl)(n-propylcyclopentanol)zirconocenes.

In od the Ohm version, high and low molecular weight polyethylene components are formed in the polymerization carried out in the presence of a bimodal catalyst system, which includes bis(2-(pentamethylbenzene)ethyl)zirconiabased or bis(2-(pentamethylbenzene)ethyl)zirconocenes.

Any of the above catalysts can be combined for the formation of a bimodal or multimodal catalyst system, as described in more detail below.

BRIEF DESCRIPTION of DRAWINGS

Figure 1 presents a graph illustrating the dynamic viscosity of the three samples in accordance with the group of variants of the invention and five commercial samples.

Figure 2 presents a graph illustrating the dependence of the strength of the melt is determined on the Rheotens unit, the speed of the tension for the two samples in accordance with the group of variants of the invention and four commercial samples.

Figure 3 presents a graph illustrating the curve of the molecular mass distribution (MMD) bimodal product (sample 1163-18-1) in accordance with a variant of the invention, using the GPC method described in the present description (GPC method).

DETAILED DESCRIPTION ISOBUTENE

Before the present compounds, components, compositions and/or methods are disclosed and described, it is necessary to understand that e is not specified, the invention is not limited to specific compounds, components, compositions, active ingredients, reaction conditions, ligand metallocene structures and the like, they may accordingly vary, except otherwise specified. It must also be understood that the terminology used in the present description, are presented to describe only specific variants of the invention and is not intended to limit the scope of the claims.

You should also pay attention to the fact that in the description and the claims, the singular number include the plural value, except otherwise specified. Thus, the reference to "leaving group", as a component of "substituted leaving group"includes more than one leaving group, so that the component can be replaced by two or more such groups. Similarly, the reference to the "halogen atom"as a component of "substituted by halogen atom"include more than one halogen atom, so that the component can be replaced by two or more of halogen atoms, the reference to "Deputy" includes one or more substituents, the reference to "a ligand" includes one or more ligands, etc.

For convenience, established various special test methods for determining such is waist, as the average molecular weight, the extrapolated voltage, the rate of polydispersity (TTD), a melt index (IL) and the melt flow index (MFR). However, when the specialist in the art reading this document and wishes to determine whether a particular property specified in the claims, has the composition or the polymer, then to determine this property can be used by any published or well-known method or test method (although it is preferable to specifically set method, and any method defined in the claims is required not only preferred). Each claim should be construed as encompassing any of these methods, even if different methods can give different results or measurements. Thus, it is expected that the specialist in the art will receive the experimental deviations defined properties, which are reflected in the claims. From the point of view of the nature of the tests, in most cases, all numeric values can be considered as "average" or "approximate" the set value.

The density representing the physical property of the composition is determined in accordance with ASTM-D-1505 and is expressed in grams per cubic the cue centimeter (or in grams per milliliter).

Except when determining the actual density, the term "high density" means any density from 0,940 g/cm³or higher, in another embodiment, 0,945 g/cm³or higher, or 0,950 g/cm³or higher, and still in another embodiment, 0,960 g/cm³or higher, and clear the interval density composition of high density is 0,945 g/cm³to 0,967 g/cm³.

The term "polyethylene" means a polymer made from at least 50% ethylene-derived units, preferably of at least 70% ethylene-derived units, more preferably of at least 80% ethylene-derived units, or 90% ethylene-derived units, or 95% ethylene-derived units, or even 100% ethylene-derived units. The polyethylene, thus, may be a homopolymer or a copolymer, including terpolymer with other monomer units. The polyethylene described in the present description, may include, for example, units derived from the co monomer, which is preferably α-olefin, e.g. propylene, 1-butene, 1-penten, 1-hexene or 1-octene, or mixtures thereof. Other options may include diene, ethacrylate or methacrylate.

The term "composition" (for example, the polyethylene composition), in its broadest sense, means any material that includes polyethylene, and may cover l is the buoy mixed composition, which not only includes a bimodal polyethylene described in the present description, but also other polymers and, optionally, additives such as carbon black, and preferably includes additives used in the preparation resin for pipes. The composition may be either a mixture (mixed) composition, which may include other polymers, for example, other polyethylene or polietilene, or "mixed" composition, which does not include other polymers. In some embodiments, the polyethylene composition" consists only of bimodal polyethylene, whereas in other embodiments, "plastic composition essentially consists of a bimodal polyethylene, i.e. with the absence of significant quantities of other materials, for example, less than 5% wt. other polymers. However, the composition that includes polimernye additives such as carbon black, is also seen as a composition consisting essentially of bimodal polyethylene.

The term "bimodal"used in the description of the characteristics of the polymer or polymer composition, for example, polyethylene, means "bimodal molecular weight distribution", this term is understood by experts in the field of technology as having the broadest definition, as reflected in one or more published articles, the sludge is issued patents. At least one example of bimodal polyethylene is shown in figure 3, where the horizontal axis depicts the logarithm of molecular weight (log MM). For example, it is believed that the composition, which includes a plastic component with at least one defined high molecular weight and a polyethylene component with at least one defined low molecular weight, for example, two peaks (as shown in figure 3), is a "bimodal" polyethylene, as the term is used in the present description. Material with more than two different peaks of the molecular mass distribution will be considered a "bimodal", as the term is used in the description, although the material may also be referred to as "multimodal composition, for example, a tri-modal or even tetravalency, etc. composition. As noted below, various types of methods and configurations of reactors can be used to obtain a bimodal polyethylene composition, including mixing in the melt, serial reactors (i.e. reactors installed sequentially) and single reactors using bimetallic catalytic systems.

It is believed that any polyethylene composition, considered as "multimodal" songs in the patent US 6579922, in the present description is subject to broadly the meaning of the term "bimodal polyethylene composition", although there are significant differences between bimodal compositions claimed in the present invention, and bimodal compositions considered in the mentioned patent. Thus, for example, one option bimodal composition is a reactor blend (also sometimes called chemical mixture), which is formed (polymerized) in a single reactor, for example, using a bimodal catalyst system (for example, a catalyst with two centers), while at least one other option bimodal composition is a physical mixture of, for example, the composition formed by post-polymerization mixture or mixing together with two odnovalnye polyethylene compositions.

The term "bimodal catalyst system" includes any composition, mixture or system that includes at least two different catalyst compounds, each of which has the same or different group metal, but, as a rule, different ligands or catalytic structure, including "dual catalyst". In another embodiment, each different catalytic connection bimodal catalyst system is located, for example, on a single carrier part, in which case it is considered that the dual catalyst is a catalyst on the carrier. Od is ako the term "bimetallic catalyst" also, in its broadest sense, includes a system or a mixture in which one of the catalysts is located on one group of particles of the carrier, and the other catalyst is located on another group of particles of the medium. Preferably, in the latter case, two catalyst on the carrier are introduced into a single reactor either simultaneously or sequentially, and the polymerization is carried out in the presence of two groups of catalysts on the media. In another embodiment, a bimodal catalyst system comprises a mixture of catalysts without media in the form of suspension.

The term "IL", in the sense in which it is used in the description, denotes the I₂₁that is determined in accordance with ASTM-1238, condition E, at 190°C.

The term "MFR : (I₂₁/I₂)"in the sense in which it is used in the description, means the ratio of I₂₁(also abbreviated as IL) I₂and I₂₁and I₂determined in accordance with ASTM-1238, condition E, at 190°C.

The term "high strength", in the sense in which it is used in the description, in its broadest sense, refers to any one or more of the group of mechanical properties, for example properties, dependent on the strength of, for example, the properties used to characterize the resin used for the reception of a pipe, in particular, the resin, which can be classified as resin PESO, or resin R is -100, or, preferably, resin D 100+. In at least preferred embodiment, high-strength polyethylene composition described in the present description, belong to the category of material RE-100, using any of the tests taken in accordance with the manufacturing, qualification resin so. Preferably, the polyethylene composition is such that in accordance with ISO 1167:1996/ SOG:1997(E) (Technical amendment 1, published 1997-03-01), entitled "Thermoplastic pipes for the transport of fluids - Resistance to internal pressure - test Method", pipe, molded from the composition that is subjected to internal pressure at selected temperatures, and has an extrapolated voltage of 10 MPa or more, when the curve of the inner strength of the pipe is extrapolated to 50 or 100 years in accordance with ISO 9080:2003(E).

The term "high molecular weight polyethylene component, in the sense in which it is used in the description means a polyethylene component in the bimodal composition, which has a higher molecular weight than the molecular weight of at least one other polyethylene component in the same composition. Preferably, such a polyethylene component has an identifiable peak, for example, as shown in figure 3. When the song includes more than two components, for example, a tri-modal composition, then the high molecular weight component should be defined as a component with the highest srednevekovoi molecular weight. In some embodiments, the high molecular weight component is a component that forms part of the bimodal composition, which has srednevekovoy molecular weight (Mw) of 400,000 to 700000. In different embodiments, the average molecular weight of high molecular weight polyethylene component may be in the range from the lower limit of 200,000 or 250,000 in or 300000, or 350000, or 400000, or to 450,000 or 500,000 to the upper limit of 1000000 or 900000, or 800000, or 700000, or 600000.

The term "low molecular weight polyethylene component, in the sense in which it is used in the present description, means a polyethylene component in the composition, which has a lower molecular weight than the molecular weight of at least one other polyethylene component in the same composition. Preferably, such a polyethylene component has an identifiable peak, for example, as shown in figure 3. When the composition includes more than two components, for example, a tri-modal composition, then the low molecular weight component should be defined as a component with the lowest srednevekovoi molecular weight. In some embodiments, the low molecular weight component is omponent, forming part of bimodal composition, which has srednevekovoy molecular weight (Mw) of from 15,000 to 35,000. In different embodiments, the average molecular weight low molecular weight polyethylene component may be in the range from the lower limit of 3000 or 5000, or 8000, or 10000, or 12000 or 15000 to an upper limit of 100,000 or 50000 or 40000, or 30,000, or 25000.

The term "srednevekovaja molecular weight" is a term used to describe a bimodal polyethylene, as described in the description, or to describe high molecular weight polyethylene component and a low molecular weight polyethylene component. In any case, the term "average molecular weight"in a broad sense, refers to any srednevekovoi molecular weight (Mw), as measured or calculated in accordance with any published method, which includes the methods, equipment and conditions in ASTM D 3536-91 (1991) and ASTM D 5296-92 (1992).

General srednekislye, srednevekovaja and z-average molecular weight are terms that refer to values of molecular weight for the composition in contrast to the values of the molecular weight of any single component. The values of the total molecular weight indicated in the claims encompass any value, as defined by any published technique, including listed what's in the paragraph above, however, preferred is a method using a GPC curve.

Srednekislye, srednevekovaja and z-average molecular weight (especially srednevekovaja molecular weight) separate plastic component specified in the claims, for example, high molecular weight component and a low molecular weight component, may also be defined by any published technique, including those mentioned in the paragraph above, but the preferred method is using any published technique of deconvolution (inverse convolution), for example, any of the published methods for the detection of molecular information of each individual polymer component in the bimodal polymer. Especially preferred is a technique that uses a deconvolution by Flory, including (but not limited to) methods Flory presented in the patent US 6534604, which fully included in the present description by reference. Used is any program that includes the principles contained in the following link: P.J. Flory, Principles of Polymer Chemistry, Cornell University Press, new York, 1953. Used is any computer program that is able to combine experimental molecular weight distribution with a multiple of Flory or log-normal statistical distributions. The distribution is s on Flory can be expressed by the following equation:

$$Y=A_o{\left(\frac{M}{M_n}\right)}^2{e}^{\left(-\frac{M}{Mn}\right)}$$

In this equation Y is the mass fraction of polymer, corresponding to molecular particles M, Mn is srednekamennogo molecular weight distribution, and A₀represents the mass fraction of the site, forming a distribution. Y can be shown as proportional to the differential molecular weight distribution (DMR), which represents the change of concentration with the change in the log of molecular weight. GPC-chromatogram depicts DMR.

Preferred is any computer program that minimizes the squared difference between the experimental and calculated distributions by varying A₀and Mn for each distribution Flory. Especially preferred is any program that can handle up to 8 Flory distribution. To implement the minimization can be used a commercially available program called Excel Solver supplied by the company Frontline Systems, Inc. (Incline Village, NV 89450, USA). When using the such program, special restrictions may be imposed on individual Flory distribution, which can harmonize the chromatogram of the experimental mixtures and bimodal distributions.

A bimodal distribution can be consistent with two separate groups of four limited distribution Flory, for a total of eight distributions. One limited group is consistent with the low molecular weight component, whereas the other group is consistent with the high molecular weight component. Each restricted group is characterized by A₀and Mn component with the lowest molecular weight in the group and relationships And₀(n)/A₀(1) and Mn(n)/Mn(1) for each of the other three distributions (n=2, 3, 4). Despite the fact that the total number of degrees of freedom for limited negotiation is the same as for the eight unlimited distribution Flory, the presence of constraints is needed to better define the contribution to the overall chromatogram separate low-molecular and high-molecular component in the bimodal polymer. Once completed the reconciliation process, the program calculates the aggregate statistics of the molecular mass and the mass percent separate high and low molecular weight components. Figure 3 presents deconvolution curve b the th separate component.

The term "slice"is defined in the present description, as a mass percentage of high molecular weight component in the bimodal composition. Thus, he describes the relative amount of high molecular weight component relative to the low molecular weight component in the bimodal polyethylene composition, including any of the polymer compositions described in the present description. The mass percentage of each component can be expressed by the area of each curve of the molecular mass distribution, which can be seen after deconvolution of the curve the total molecular mass distribution.

The term "dispersion", in the sense in which it is used in the present description, means the ratio of srednevekovoi molecular weight of high molecular weight polyethylene component, sometimes referred to as Mw_BMMto srednevekovoi molecular weight low molecular weight polyethylene component, sometimes referred to as Mw_HMM. "Scatter" can therefore also be expressed as the ratio Mw_BMM:Mw_HMM- Srednevekovaja molecular mass of each component can be obtained by deconvolution of the overall civil-curve, i.e. the GPC curve of the entire composition.

The term "DPP", in the sense in which it is used in the description indicates the index of polydispersity and means the same thing, ctoi "MMD" (molecular weight distribution), this term is understood by experts in the field of technology as having the broadest definition, as reflected in one or more published publications or issued patents. TTD (DFID) is the ratio srednevekovoi molecular weight (Mw) to srednekamennogo molecular weight (Mn), i.e., Mw/Mn.

As noted below, some properties or characteristics of the compositions, polymers, pipes, or catalytic systems is expressed in the values of the lower limits (e.g., X or more) or upper limits (e.g., Y or less). It is clear that any of the lower limits can be combined with any of the upper limits in order to create a number of alternative intervals.

For any pipe obtained from any one of the high-strength bimodal polyethylene compositions described in the present description, when it is subjected to the full test hydrostatic strength in accordance with ISO 1167, extrapolated voltage can be 10.5 MPa or more in extrapolating to 50 or 100 years in accordance with ISO 9080:2003(E). Mainly, provides a number of alternative values extrapolated voltage. For example, in extrapolating to 50 or 100 years, in accordance with ISO 9080:2003(E), the extrapolated voltage can reach 10.1 MPa or more, or 10.2 MPa or more, and the and 10.3 MPa or more, or 10.4 MPa or more, or 10.5 MPa or more, or 10.6 MPa or more, or about 10.7 MPa or more, or 10.8 MPa or more, for example, to 15.0 MPa, or any combination of the above upper and lower limits.

In any of the compositions described above or elsewhere in the description, the strength of the melt can be more than 17 SN, more than 18 SN, more than 19 CH 20 CH, more than 21 SN, more than 22 SN, about 23 SN, more than 24 CH, more than 25 mV, 18 mV to 30 mV or 20 mV to 30 mV, or from 22 CH 30 CH.

In any of the compositions described above or elsewhere in the description, high molecular weight polyethylene component may have a lower limit of the density 0,920 g/ml or more or 0,925 g/ml or more, or 0.930 g/ml or more, and the upper limit of the density 0,945 g/ml or less or 0,940 g/ml or less, or 0.935 g/ml or less.

In any of the compositions described above or elsewhere in the description, low molecular weight polyethylene component may have a lower limit of the density 0,940 g/ml or more or 0,945 g/ml or more, or 0,950 g/ml or more, and the upper limit of the density 0,965 g/ml or less, or 0,960 g/ml or less, or 0,955 g/ml or less.

In any of the compositions described above or elsewhere in the description, srednevekovaja molecular weight (Mw) of low molecular weight polyethylene component may be, for example, from 15,000 to 35,000, or be in any of the intervals located between each the mi lower and upper limits, discussed elsewhere in the description.

In any of the compositions described above or elsewhere in the description, srednevekovaja molecular weight (Mw) of high molecular weight polyethylene component may be, for example, from 400,000 to 700000, or be in any of the intervals located between the other of the lower and upper limits, are considered elsewhere in the description.

In any of the compositions described above or elsewhere in the description, high molecular weight polyethylene component may include polyethylene, which includes comonomer representing butene, hexene and octene, or mixtures thereof, where comonomer is present in the amount of 1.0 wt.%, or, preferably, more than 2.0 wt.%, or, more preferably, more than 3.0 wt.%, relative to the weight of polyethylene.

In any of the compositions described above or elsewhere in the description, low molecular weight polyethylene component may include polyethylene, which includes comonomer representing butene, hexene and octene, where comonomer is present in the amount of 3.0 wt.%, or, preferably, less than 2.0 wt.%, or, more preferably, less than 1.0 wt.%, relative to the weight of polyethylene.

In one or more of the high strength compositions, described, the weight percent of high molecular weight polyethylene component, also called a "slice"ka is described above, up to 45 wt.% or more relative to the weight of the composition. In alternative embodiments, high molecular weight polyethylene component may be 46 wt.% or more, 47 wt.% or more, 48 wt.% or more, 49 wt.% or more, or 50 wt.% or more relative to the weight of the composition. And, Vice versa, in any of the above high-strength compositions of high molecular weight polyethylene component may be 60 wt.% or less relative to the weight of the composition, or 59 wt.% or less, 58 wt.% or less, 57 wt.% or less, 56 wt.% or less, 55 wt.% or less, 54 wt.% or less, 53 wt.% or less, or 52 wt.% or less, or any combination of the above upper and lower limits. In a specific embodiment, a "slice" is from 45 wt.% up to 60 wt.%, 48 wt.% up to 56 wt.%, from 50 wt.% up to 52 wt.% or 51 wt.%.

In one or more of the high strength compositions, described, against, spread, Mw_BMM:Mw_HMMas defined above, may be 15 or more, 17 or more, 19 or more, 21 or more, 40 or less 36 or less 32 or less 28 or less, 25 or less, or any combination of the above upper and lower limits, or from 15 to 40, from 17 to 35, from 19 to 29, from 21 to 23 or 22.

In one or more of the high strength compositions, described, IL (I₂₁) compositions may be in the range from 4 to 10 g/10 min. At alternative options, which the ants, IL can be expressed as in any one of a number of intervals, for example, with a lower limit of 4 g/10 min or higher, or 5 g/10 min or higher, or 6 g/10 min or higher, or 7 g/10 min or higher, or 8 g/10 min or higher, or 9 g/10 min or higher; together with an upper limit of 10 g/10 min or less, or 9 g/10 min or less, or 8 g/10 min or less or 7 g/10 min or less, or 6 g/10 min or less, or 5 g/10 min or below, or any combination of the above upper and lower limits. In one embodiment, M is from 4 to 10 g/10 minutes

In one or more of the high strength compositions, described, PTR (I₂₁/I₂may be in the range from 100 to 250. In alternative embodiments, the TPP can be expressed in any one of a number of intervals, for example, with a lower limit of 50 or 60, or 70, or 80, or 90, or 100, or 110, or 120, or 130, or 140 or 150; together with an upper limit of 150, or 180, or 200, or 220, or 250, or 270, or 300, or 320, or 350, or any combination of the above upper and lower limits.

In one or more of the high strength compositions, described, SCD, of the entire composition can be expressed, as being in any one of a number of intervals, for example, with a lower limit of 10 or 15; together with an upper limit of 45 or less, or 40 or less, or 35 or less, or 30 or less, 25 or less, or any combination of the above upper the lower limits. In a specific embodiment, the RPE may be from 15 to 40, or from 17 to 31, or from 19 to 22 or 20.

In one or more of the high strength compositions, described, TTD high molecular weight component can be more than 3.5. In alternative embodiments, the DPP by the high molecular weight component can be expressed as in any one of a number of intervals, for example, with a lower limit of 3.0 or more, or 3.5 or more, or 4.0 or more, or 4.5 or more, or 5.0 or more, or 5,5 or more, or 6.0 or more; together with an upper limit of 6.0 or less, or any combination of the above upper and lower limits.

In one or more of the high strength compositions, described, SCD, low-molecular-weight component may be 2.5 or more, In alternative embodiments, SCD, low-molecular weight component can be expressed as in any one of a number of intervals, for example, with a lower limit of 2.0 or more, or 2.5 or more, or 3.0 or more, or 3.5 or more; together with an upper limit of 5.0 or less, or 4.5 or less, or 4.0 or less, 3.5 or less, or any combination of the above upper and lower limits.

In one or more of the high strength compositions, described, the average molecular weight of the entire composition can be 200000 or more. In alternative embodiments, the average MOLEKULYaRNAYa of the entire composition can be expressed, as being in any one of a number of intervals, for example, with a lower limit of 50,000 or more, or 100,000 or more, or of 150,000 or more, or of 200,000 or more, or 250000 or more, or of 300,000 or more, or of 350,000 or more, or of 400,000 or more, or of 450,000 or more, with the upper limit of 1000000 or less, or nearly 900,000 or less, or 850000 or less, or of 800,000 or less, or the 750,000 or less, or the 700,000 or less, or about 650,000 or less, or of 600,000 or less or of 550,000 or less, or 500,000 or less, or of 450,000 or less, or of 400,000 or less, or any combination of the above upper and lower limits.

In one or more of the high strength compositions, described, average molecular weight (Mw) of low molecular weight component is preferably 15000 or more; or 18000 or more; or 22000 or more; and is, preferably, 35000 or less; or 32000 or less; or 28000 or less, or in the intervals represented by any combination of the above upper and lower limits. In a specific embodiment, the Mw of low molecular weight component can range from 15000 to 35000 or 25000.

In one or more of the high strength compositions, described, high and low molecular weight polyethylene components can be obtained in a single reactor. Examples of such reactors are considered in more detail.

In one or more of isocaproic compositions, considered in the description, high and low molecular weight polyethylene components can be obtained in the process of gas-phase polymerization. A detailed description of acceptable gas-phase polymerizati revealed next.

One or more of the high strength compositions described can be obtained by polymerization carried out in the presence of a bimodal catalyst system that includes a catalyst based on metallocene.

In one or more of the high strength compositions, described, high and low molecular weight polyethylene components can be obtained by polymerization carried out in the presence of a bimodal catalyst system, which includes bis-(2-(trimethylaniline)ethyl)lincolniensis.

In one or more of the high strength compositions, described, high and low molecular weight polyethylene components can be obtained by polymerization carried out in the presence of a bimodal catalyst system, which includes bis-(2-(pentamethylbenzene)ethyl)lincolniensis.

In one or more of the high strength compositions, described, high and low molecular weight polyethylene components can be obtained by polymerization carried out in the presence of b is the modal catalytic system, which includes (pentamethylcyclopentadienyl)(n-propylcyclopentanol)zirconiated.

In one or more of the high strength compositions, described, high and low molecular weight polyethylene components can be obtained by polymerization carried out in the presence of a bimodal catalyst system, which includes (tetramethylcyclopentadienyl)(n-propylcyclopentanol)zirconiated or (tetramethylcyclopentadienyl)(n-propylcyclopentanol)zirconocenes.

In one or more of the high strength compositions, described, high and low molecular weight polyethylene components can be obtained by polymerization carried out in the presence of a bimodal catalyst system, which comprises bis(n-butylcyclopentadienyl)zirconiated or bis(n-butylcyclopentadienyl)zirconocenes.

Bimodal polyethylene composition

As noted above, high strength bimodal polyethylene composition preferably has a density 0,940 g/cm³or more and includes (and in some embodiments consists of or essentially consists of a) high molecular weight polyethylene component having a high srednevekovoy molecular weight (Mw_BMM), and low molecular weight polyethylene component having a low srednevekov the th molecular weight (Mw _HMM), and: the song belongs to the category of material PE 100, such that, in accordance with ISO 1167, pipe, molded from the composition that is subjected to test of inner strength, has extrapolated voltage of 10 MPa or more, when the curve of the inner strength of the pipe is extrapolated to 50 or 100 years in accordance with ISO 9080:2003(E); and the strength of the melt is more than 18 CH. As noted in the description of the individual options, similarly, the extrapolated voltage can be higher and is preferably of 10.5 MPa or higher, and even to 10.7 MPa or higher.

At least one private embodiment, the composition includes a bimodal polyethylene composition obtained using any of the catalyst systems described above, but not limited to, demonstrated in the present description.

As noted above, the bimodal polyethylene composition preferably have a high molecular weight component and a low molecular weight component. Preferably, the high molecular weight component has a lower density than the density of the low molecular weight component. In addition, the high molecular weight component preferably has a higher content of co monomer than the content of the co monomer low molecular weight component. The content of the co monomer can be expressed as kislomolochnyh branches per 1000 carbon atoms. In some embodiments, the number comonomeric branches per 1000 carbon atoms to low molecular weight component is from 0 to 2, preferably 1 or less. In some embodiments, the number comonomeric branches per 1000 carbon atoms to high molecular weight component is from 2 to 5, preferably 2 or more, more preferably more than 3.

Methods of polymerization

The method of polymerization used for any of the polymers described in the present description, for example, can be carried out using any suitable method, for example, high pressure, solution, slurry and gas-phase. Some of the polyethylene can be obtained using the method of gas-phase polymerization, for example, by using a reactor with a fluidized bed. A reactor of this type and method of action of the reactor are well known and fully described, for example, in US 3709853; US 4003712; US 4011382; US 4302566; US 4543399; US 4882400; US 5352749; US 5541270; EP-A-0802202 and BE 839380. These patents disclose methods of gas-phase polymerization in which the polymerization medium or mechanically mixed or pseudogiants continuous flow of the gaseous monomer and diluent.

The method of polymerization may be carried out as a continuous gas-phase method such as a method of fluidized bed. Rea is Thor fluidized bed may contain a reaction zone and a so-called zone speed reduction. The reaction zone may contain a layer of growing polymer particles, formed polymer particles and a minor amount of catalyst particles fluidized by the continuous flow of the gaseous monomer and diluent, with the heat of polymerization from the reaction zone. Optionally, a portion of the recycled gases may be cooled and compressed with the formation fluids, which increases the ability to remove heat recirculating gas flow when re-entering the reaction zone. Matching the velocity of the gas flow can easily be determined by simple experiment. The flow of the gaseous monomer in the circulating gas flow is at a rate equal to the rate at which a particular polymer product and the associated monomer is removed from the reactor, and the composition of the gas passing through the reactor is controlled by maintaining an essentially steady state gaseous composition within the reaction zone. The gas discharged from the reaction zone is passed into a zone of lower velocity, where the captured particles are removed. Small captured particles and dust can be removed in a cyclone and/or filter. The gas is passed through a heat exchanger in which heat is given polymerization, is compressed in the compressor and then is returned to the reaction zone.

The temperature of the PE the work method, fluidized bed, preferably, in the range of 30°C or 40°C or 50°C to 90°C or 100°C. or 110°C. or 120°C. typically, the reaction temperature is set at the highest temperature, which allowed taking into account the sintering temperature of the polymer product in the reactor. Regardless of the method used to obtain polyolefins according to the invention, the polymerization temperature or the reaction temperature should be below the melting temperature, or "sintering" of the obtained polymer. Thus, the upper temperature limit in one embodiment, is the melting point of the polyolefin obtained in the reactor.

Can also be used a method of suspension polymerization. The method of suspension polymerization generally uses pressures in the range from 1 to 50 atmospheres and even greater and temperatures in the range from 0°C to 120°C, and in particular from 30°C to 100°C. In a slurry polymerization, a suspension of a solid dispersed polymer is formed in a liquid polymerization medium diluent in which you enter ethylene and comonomers and, in many cases, hydrogen along with catalyst. The suspension containing the diluent, periodically or continuously removed from the reactor, after which the volatile components are separated from the polymer and get recycled, optionally after distillation reactor. The liquid diluent used in isoamyl in a polymerization medium, typically an alkane having from 3 to 7 carbon atoms, in one embodiment, a branched alkane. The medium used should be liquid under the conditions of polymerization and to be relatively inert. When the use environment of the propane method should be above the critical temperature and pressure of the reaction diluent. In one embodiment, as the environment is used hexane, isopentane or isobutane.

Also used is the polymerization in the form of particles, a method in which the temperature is maintained below the temperature at which the polymer goes into solution. Other suspension methods include methods using a circulation reactor, and methods that use multiple reactor with an agitator arranged in series, in parallel or by their combination. Non-limiting examples of suspension methods include methods with continuous circulation or container with continuous stirring. Also, other examples of the suspension of the methods described in US 4613484 and 2 Metallocene-Based Polyolefins 322-332 (2000).

Such methods can be used to obtain homopolymers of olefins, in particular ethylene and/or copolymers, terpolymers and other olefins, in particular ethylene, and at least one or more other olefin(s). Preferably, the olefins are α-olefins. In one embodiment, the olefin is, for example, can contain from 2 to 16 carbon atoms, in another embodiment, the ethylene and comonomer containing from 3 to 12 carbon atoms, in another embodiment, the ethylene and comonomer containing from 4 to 10 carbon atoms, and in another embodiment, the ethylene and comonomer containing from 4 to 8 carbon atoms. Especially preferred are polyethylene. Such polyethylene are preferably homopolymers of ethylene and interpolymer of ethylene and at least one α-olefin, in which the ethylene content is at least about 50 wt.% from all monomers. Examples of olefins that can be used in the present invention are ethylene, propylene, 1-butene, 1-penten, 1-hexene, 1-hepten, 1-octene, 4-methylpent-1-ene, 1-mission 1-dodecene, 1-hexadecene etc. used in the invention are the polyene, such as, 1,3-hexadiene, 1,4-hexadiene, cyclopentadiene, Dicyclopentadiene, 4-vinylcyclohexane-1-ene, 1, 5cyclooctadiene, 5-vinylidene-2-norbornene and 5-vinyl-2-norbornene, and olefins formed in place in the curing environment. When olefins are formed in place in a polymerization medium, may be the formation of polyolefins containing long branching chains.

Upon receipt of polyethylene or polypropylene in a polymerization reactor can contain comonomers. If present with Homer, it may be present at any level in relation to ethylene or propylene to a monomer, which provides the necessary mass percentage introduction of co monomer in the final resin. In one embodiment, the low-density polyethylene production, comonomer present with ethylene in a molar ratio in the range from 0.0001 (comonomer:ethylene), 50, and from 0.0001 to 5 in another embodiment, and from 0.0005 to 1.0 in another embodiment, and from 0.001 to 0.5 - in another version. Expressed in absolute values upon receipt of polyethylene, the amount of ethylene present in the polymerization reactor may be in the range of pressures up to 1000 ATM in one embodiment, and up to 500 ATM in another embodiment, and up to 200 ATM in another embodiment, and up to 100 ATM in another embodiment, and up to 50 ATM in another version.

Hydrogen gas is often used in the polymerization of olefins to control the final properties of the polyolefin as described in the Handbook of Polypropylene Handbook 76-78 (Hanser Publishers, 1996). Some catalytic systems, the increase in the concentration (partial pressure) of hydrogen can increase the rate of flow of the melt (P) (also referred to in the description, as the melt index (IR) of the obtained polyolefin. Thus, P, or R & d can influence the concentration of hydrogen. The amount of hydrogen in the polymerization can be expressed, the AK molar ratio relative to all the monomer polymerized, for example, ethylene or mixtures of ethylene and hexane, propylene, pentene and mixtures thereof. The amount of hydrogen used in the polymerization process according to the present invention, represents the amount needed to achieve the desired PAGE, or IL, the end of the polyolefin resin. In one embodiment, the molar ratio of hydrogen to the entire monomer (H2:monomer) is in the range from more than 0,0001, and from more than 0,0005 in another embodiment, and from more than 0.001 in another embodiment, to less than 10 in yet another embodiment, and less than 5 in another embodiment, and less than 3 in another embodiment, and less than 0.10 to still another embodiment, and suitable interval may contain any combination of any upper limit of the molar relationship with any lower limit of the molar relationship described in the description. Expressed another way, the amount of hydrogen in the reactor at any time may be in the range of up to 5000 hours/million - in one embodiment, and up to 4000 ppm million in another embodiment, and up to 3000 ppm million - even in another embodiment, and between 50 part./million up to 5000 hours/million - even in another embodiment, and in the interval from 500 ppm million to 2000 ppm million - in a different version.

Moreover, typically use a multi-stage reactor using two or more reactors arranged in series, where one reactor can be obtained, for example, high-molecular component, and in the other the second reactor can receive low-molecular-weight component. In one embodiment of the invention, the polyolefin is obtained using multistage gas-phase reactor. Such industrial polymerization system is described, for example, 2 Metallocene-Based Polyolefins 366-378 (John Scheirs & W.Kaminsky, eds. John Wiley & Sons, Ltd. 2000), US 5665818, US 5677375, US 6472484, EP 0517868 and EP-A-0794200.

The pressure in one or more reactors in gas-phase method (either in one stage or in two or more stages) can vary from 100 psig (690 kPa) to 500 psig (3448 kPa) and is in the range of from 200 psig (1379 kPa) to 400 psig (2759 kPa) - in another embodiment, in the range of from 250 psig (1724 kPa) to 350 psig (2414 kPa) is another option.

Gas-phase reactor using the catalyst system described in the present description, provides the possibility of obtaining from 500 lbs of polymer per hour (227 kg/HR) up to 200,000 lb/h (90900 kg/h), and more than 1000 lbs/HR (455 kg/HR) - in another embodiment, and more than 10,000 lbs/HR (4540 kg/HR) - even in another embodiment, and more than 25,000 lbs/HR (11300 kg/h) - yet in another embodiment, and more than 35,000 lbs/HR (15900 kg/h) - yet in another embodiment, and more than 50,000 lb/h (22700 kg/h) - yet in another embodiment, and from 65000 lb/h (29000 kg/h) up to 100,000 lb/h (45500 kg/h) - in another version.

Suspension or gas-phase method can be carried out in the presence of a metallocene catalyst system of the type and in the absence of the or essentially in the absence of any scavengers, such as, triethylaluminum, trimethylaluminum, tri-isobutylamine and tri-n-hexylamine and diethylaluminium, dibutyltin etc. Under the term "essentially in the absence of" is meant that these compounds are not specifically added to the reactor or in any of the components, but if they are present, they are present in the reactor in the amount less than 1 part./million

One or all of the catalysts can be mixed with metal connection and fatty acids, such as, for example, aluminum stearate, in an amount up to 10 wt.%, in relation to the weight of the catalytic system (or its components), as discussed in US 6300436 and US 5283278. Other suitable metals include other metals of Group 2 and Group 5-13. In another embodiment, a solution of metal joining and fatty acids are fed into the reactor. In yet another embodiment, the compound of the metal and a fatty acid mixed with catalyst and fed into the reactor separately. Such agents can be mixed with the catalyst or can be fed into the reactor in the form of a solution or suspension with or without catalytic system or its components.

The catalyst(s) on the media can be mixed with activators, and can be mixed by mixing in a drum or other suitable means, with up to 2.5 wt.% (by weight of the catalytic composition) additives that reduce static charges, such ka is, ethoxylated or methoxycarbonyl amine, an example of which is Kemamine AS-990 (ICI Specialties, gamblingcom, stduser).

EXAMPLES

In the present invention, it is understood that the above description is intended to illustrate and not to limit the scope of the present invention, as the present invention is described in conjunction with specific variants of its execution. Other features, advantages and modifications of the invention will be apparent to a person skilled in the art to which the present invention relates.

In view of the above, the following examples are set forth so as to provide to a person skilled in the art a complete disclosure and description of how to make and use the compounds of the present invention, and are not intended to limit the scope, which the inventors regard as their invention.

In the following examples, consider some of the properties and other characteristics of the bimodal polyethylene compositions that belong to the category of material RE-100 and, in addition, have a surprisingly high strength melt.

Table 1. The properties of the composition in accordance with a variant of the invention and four commercial compositions.

Referring to Tables 1 and 2, Qenos HDF-193™ available from Qeno Pty Ltd, Altona, stevedore, Australia. Atofina XS10H™ available from Arkema Canada, garvill, preventoria, Canada. Borealis HE3490™ and Borialis HE3490 LS™ available from Borealis Oy, goroo, Finland ("NP" refers to "low sagging"). CRP 100 Pipe™ available from LyondellBasell Industries, gatterdam, the Netherlands.

Figure 1 presents a graph illustrating the dynamic viscosity of the three samples in accordance with the tvii variant of the invention under examination (all marked as 1163-18-1, given that were applied in the same conditions, the readings for the samples were filmed at different times) and five commercial samples. Dynamic viscosity is measured using a Rheometrics (Piscatway, NJ, USA) rheometer dynamic voltage, model SR-200 at 190°C and a shear rate in the range from 0.01 to 100 s^-1.

Figure 2 presents a graph illustrating the dependence of the strength of the melt is determined on the Rheotens unit, the speed of the tension for the two samples in accordance with the variants of the invention under examination and four commercial samples. The melt strength is measured using a GottFert (Rock Hill SC, USA) Rheo-Tester 2000 under the following conditions: Instrument: Rheo-Tester 2000; test temperature: 190°C; the head of the extruder length /diameter: 20 mm/2 mm; the diameter of the cylinder of the extruder: 15 mm; initial speed: 9.5 mm/s; acceleration: 2.4 mm/s²; the length between the head of the extruder and rollers: 130 mm, and the gap between the rollers: 0,5 mm

Example 1

Product bimodal polyethylene resin, hereinafter referred to as "bimodal product, obtained using gas-phase polymerization in dorectory system with a catalytic system, spray dried, which includes bis-(2-(pentamethylbenzene)ethyl)zirconiabased together with (tetramethylcyclopentadienyl)(n-propylcyclopentanol)ciconiidae the om in a molar ratio of 3.0:1. Such catalytic systems commercially available from Univation Technologies, LLC (Houston, Texas) and sold under the name PRODIGY™ bimodal catalysts. In the reactor also serves modified methylalumoxane (MMAO). Using the "dry method", meaning that the material is injected in the form of a dry powder (granules). Samples obtained bimodal product have IL 5-7; density from 0,947 to 0,950, and the TPP approximately 170-200. Typical reaction conditions for the product are summarized in Table 3: the mass layer=34000 pounds; the density of the fluidized bed=13-19 lbs/ft³; SGV (specific volume velocity)=2-2,15 ft/s; dew point=55-60°C, S=from 10%to 12%.

Resin properties

Mixed granular samples bimodal product get on line mixing Kobe LCM-100 (Kobe Steel, Ltd., Xero, Japan), equipped with EL-2 rotors, using the mixing additives, namely, 2000 ppm million-225 (Irganox™ 1010 and Irgafos™ 168 in the ratio 1:1) and 500 ppm million CaSt. Black carbon is injected at the rate of 2.25 wt.% by filling. The obtained granular samples to determine the flow properties of the melt, density and examined by gel permeation chromatography (GPC), as described below.

Table 4 presents the rheological properties of the two samples bimodal product. Sample 1163-18-1 is a bimodal product prepared without carbon black, natural grade (NS)obtained from the dry catalytic systems (installations is authorized above). Sample 1163-18-1 VK is a bimodal product, which includes shaunaolney mixture, but in other respects is identical to the sample 1163-18-1. Shaunaolney mixture is a Royal concentrate containing carbon soot. It is noted that the introduction shaunaolney mixture has little effect on the overall rheological properties, but the density increases by about 0.01 g/cm³and the result is a density of about component 0,9597 g/cm³.

Characteristics

3 shows the curve of the molecular mass distribution (MMD), based on the bimodal sample product sample 1163-18-1) using GPC techniques described in the description (GPC method), on which there are two peaks, one of which corresponds to a relatively low molecular weight component, and the other corresponds to the high-molecular component. In the following table 5 shows the GPC molecular data and the results of deconvolution for such samples. Total Mw are in the range from about 312000 to 415000, and the total MP lie in the range from approximately 13000 to 14500. Overall polydispersity (TTD) ranges from 23.4 to 28,5. AMM component, or a "slice"is 52-53 wt.%, and TTD AMM component is 4.7. "Variance", i.e. the ratio of Mw_BMM^KMw_HMM,22.6.

Operational data the slow growth of cracks

Operational data the slow growth of cracks is checked using the tests with notched pipes, ISO 13479. MRI test cutting is carried out for 4 inch SDR11 pipe. Used by the test conditions are the I 80°C and a pressure of 9.2 bar. The average uptime for the three examples sample 1163-18-1 was 3672 hours, which exceeds the requirement for RE-100≥500 hours.

For sample 1163-18-1, on samples of a certain size, perform a test cut on the Pennsylvania (PENT) and impact test on Charpy. PENT (ASTM F 1473-94) is a laboratory of the selection test with small samples to assess the resistance of pipes to the slow growth of cracks. The bimodal samples of the product in the form of granulated resin molded by compression molding with getting plates for PENT in accordance with ASTM. Of plates cut three rectangular pattern and are mounted on stands for PENT-tests.

Two of the three samples made from the same sample 1163-18-1 bimodal product is kept in the range from 1800 h to 2600 hours

The test pipe extrusion

Next, ekstragiruyut pipes for long-term hydrostatic testing, external testing laboratory. The extruder for pipes served extruder model Maplan SS60-30. The molten pipe profile emerging from the annular head of the extruder, stretch from the head clearance of the extruder within the calibrating sleeve pulling device located further downstream. When the pipe moves through the calibrating sleeve, vacuum pushes the melted profile inside ulki. Cooling water enters the chamber, cooling tube and supporting the set dimensions. Receive nominal 32 mm SDR 11 pipes of high quality with a smooth surface.

Test tubes for short-term hydrostatic strength

Standardized testing the internal pressure of plastic pipe installed in ISO 1167, entitled "Thermoplastic pipe for transporting fluids - Resistance to internal pressure - test Method". The test specifies a method for determining resistance to permanent internal pressure at constant temperature. The test requires that the samples were kept in an environment at a certain temperature, which may be water (test, "water-in-water"), other liquid (test, "water-in-liquid) or air (test, "water-in-air").

Hydrostatic testing is performed, as described in ISO 4437, table 8 in accordance with ISO 1167. This test is a qualifying test for intermittent hydrostatic pressure, which is held at three separate hydrostatic conditions. ISO 4437 defines three separate indicator for resins PE-80 and PE-100. Tests are conducted on 32 mm SDR 11 pipes (thickness 3 mm)as a test of "water-in-water". With regard to the length of the pipe, the standard requires that it is at least three times the outer diameter. In this case, the pipe length is 350 mm

Samples of pipes made from bimodal product (sample 1163-18-1, which includes carbon soot, hereinafter referred to as sample 1163-18-1 VK), incubated under three conditions required for RE-100. Table 6 presents the results of tests on short-term hydrostatic strength, as described in ISO 4437, in accordance with ISO 1167, for pipe samples made from the sample 1163-18-1 VK.

It should be noted that in all cases the sample 1163-18-1 VC exceeds the criterion by the time of the destruction for RE-100, which is defined in ISO 4437.

Unless otherwise indicated, the phrase "essentially contain" and "essentially contains a" do not exclude the presence of other steps, elements, or materials, regardless of negotiated it in this specific way, or there is no such stage, elements or materials do not affect the basic and novel characteristics of the present invention, additionally, they do not exclude impurities, usually pertaining to items and materials.

For brevity, only certain ranges of values are described in detail in the present description. However, the intervals from any lower limit can be combined with any upper limit to describe interval not listed in detail, also, the intervals from any lower limit can be combined with any other lower limit to describe interval not listed in detail, exactly the same intervals from any upper limit can be combined with any upper limit to describe what interval, not listed in detail. In addition, the range includes any point or single value between its endpoints, despite the fact that are not described in detail. Thus, any point or single value can be used as your own lower or upper limit combined with any other point or a single value or any other lower or upper limit, to describe interval not listed in detail.

All priority documents included in this description in full by reference for all legal documents, in which such incorporation is permitted, and if such disclosure is in accordance with the description of the present invention. Moreover, all documents and references cited in the present description, including measurement techniques, publications, patents, article magazines, etc. included in this description in full by reference for all legal documents, in which such incorporation is permitted and if such disclosure is in accordance with the description of the present invention.

Despite the fact that the present invention is presented in relation to specific options and examples for professionals in the art having the benefits of this disclosure, it will be obvious that there may be atrabotana other options which do not deviate from the scope and General direction of the present description.

1. Bimodal polyethylene composition having a density 0,940 g/cm³or more, including high molecular weight polyethylene component and a low molecular weight polyethylene component, in which high and low molecular weight polyethylene components are formed in a single reactor, with:
the composition belongs to the category of material PE 100, such that in accordance with ISO 1167 pipe, molded from the composition that is subjected to test of inner strength, has extrapolated voltage is 10 MPa or more, when the curve of the inner strength of the pipe is extrapolated to 50 or 100 years in accordance with ISO 9080:2003(E);
it has the strength of the melt 18 mV or more; and
the ratio srednevekovoi molecular weight of high molecular weight of the component (Mw_BMMto srednevekovoi molecular weight low molecular weight component (Mw_HMMsong is more than 15:1 and 28:1.

2. The composition according to claim 1, in which the melt strength is more than 20 CH.

3. The composition according to claim 1, in which the strength of the melt is more than 22 CH.

4. The composition according to claim 1, in which the complex viscosity at a frequency of 0.01 c^-1is more than 3.5·10⁵PA·S.

5. The composition according to claim 1, in which the complex viscosity at the hour of the rat 0.01 ^-1is more than 1.5·10⁵PA·S.

6. The composition according to claim 1, which has a total TTD from 15 to 40.

7. The composition according to claim 1, in which the high molecular weight component is present in an amount of from 45 to 60 wt.%.

8. The composition according to claim 1, in which the average molecular weight (Mw) of low molecular weight polyethylene component is from 5000 to 35000.

9. The composition according to claim 1, in which the average molecular weight (Mw) of high molecular weight polyethylene component is of 400,000 to 700,000.

10. The composition according to claim 1, which has IL (I₂₁from 4 to 10 g/10 minutes

11. The composition according to claim 1, in which the high molecular weight polyethylene component has a density 0,945 g/ml or less.

12. The composition according to claim 1, in which the low molecular weight polyethylene component has a density 0,940 g/ml or more.

13. The composition according to claim 1, in which the high molecular weight polyethylene component includes polyethylene, which includes comonomer representing butene, hexene, octene, and mixtures thereof, where comonomer is present in the amount of more than 1.0 wt.% relative to the weight of polyethylene.

14. The composition according to claim 1, in which the low molecular weight polyethylene component includes polyethylene, which includes comonomer representing butene, hexene, octene, and mixtures thereof, where comonomer is present in amount of less than 3.0 wt.% relative to the weight polyethylene

15. The composition according to claim 1, in which the extrapolated voltage is 10.5 MPa or more, when extrapolated to 50 or 100 years in accordance with ISO 9080:2003(E).

16. The composition according to claim 1, in which the high and low molecular weight polyethylene components are formed during gas-phase polymerization.

17. The composition according to claim 1, which is obtained by polymerization carried out in the presence of a bimodal catalyst system that includes a catalyst based on metallocene.

18. The composition according to claim 1, in which the high and low molecular weight polyethylene components are formed in the polymerization carried out in the presence of a bimodal catalyst system, which includes bis(2-(trimethylaniline)ethyl)lincolniensis.

19. The composition according to claim 1, in which the high and low molecular weight polyethylene components are formed in the polymerization carried out in the presence of a bimodal catalyst system, which includes bis(2-(pentamethylbenzene)ethyl)lincolniensis.

20. The composition according to claim 1, in which the high and low molecular weight polyethylene components are formed in the polymerization carried out in the presence of a bimodal catalyst system, which includes (pentamethylchroman yanil)(n-propylcyclopentanol)zirconiated.

21. The composition according to claim 1, in which the high and low molecular weight polyethylene components are formed in the polymerization carried out in the presence of a bimodal catalyst system, which includes (tetramethylcyclopentadienyl)(n-propylcyclopentanol)zirconiated or (tetramethylcyclopentadienyl)(n-propylcyclopentanol)zirconocenes.

22. The composition according to claim 1, in which the high and low molecular weight polyethylene components are formed in the polymerization carried out in the presence of a bimodal catalyst system, which includes bis(2-(pentamethylbenzene)ethyl)zirconiabased or bis(2-(pentamethylbenzene)ethyl)zirconocenes.