High-density polyethylene

FIELD: chemistry.

SUBSTANCE: invention describes multimodal polyethylene which is suitable for use as a film, as well as a pipe. The polyethylene is characterised by density between 0.940 and 0.965 g/cm3, flow melt index l21 between 4 and 20 dg/min. The polyethylene contains a low-molecular ethylene copolymer, having weight-average molecular weight between 5000 and 50000 amu, characterised by short-chain branching index between 2.5 and 4.5; and high-molecular ethylene copolymer, having weight-average molecular weight between 60000 and 800000 amu, characterised by short-chain branching index between 2 and 2.5. The invention also describes multimodal polyethylene, where the weight ratio of the high-molecular ethylene copolymer in terms of the overall multimodal composition is between 0.3 and 0.7. The ratio of branching indices of the low- and high-molecular ethylene copolymers is between 1.2 and 6.0.

EFFECT: balance of short-chain branches makes multimodal polyethylene suitable for use in making films, pipes, in fields using centrifugal moulding and blow moulding.

23 cl, 5 dwg, 6 tbl, 4 ex

 

The technical field

The present invention relates to a multimodal polyethylene compositions of high density containing at least low and high molecular weight ethylene copolymer, and, in particular, the multimodal polyethylene of high density, characterized by the frequency of branching, which allows the use of polyethylene in applications centrifugal molding and blow molding, as well as pipes and films.

The level of technology

Plastic compositions containing at least two or more ethylene copolymers having different molecular weight, known state of the art. Such compositions are often used in such products as films and pipes. Typically, the composition, which is suitable for use in films, is not suitable for use in pipes or in the products manufactured by the method for blow molding or centrifugal molding. Suitable for use would be "multimodal" polyethylene, which are suitable for all these applications.

It is known that the type and number of branches in the form of side chains in multimodal polyethylene may have an impact on the final properties of the products made from them. In particular, in the works of K. Ebner,Bi-Modal HDPE for Piping Systems and Further Applications in Adv. Plast. Technol. APT, Int. conf. 1-8 (1997) and J. Scheirs et al.,PE100 Resins for Pipe Applicationsin 4(12) Trends in Poly. Sci. 408-415 (1996) found that bimodal polyethylenes having the most branches in the relatively high-molecular fraction, are the most ideal. Typically, the polyethylene suitable for use in pipes, such as are described in the document US 6867278 contain a composition of low and high molecular weight fractions, where the majority of branches or all the ramifications of it are in high molecular weight fractions. But what is not described is polyethylene is characterized by the desired number of branches, which would allow to obtain the multifunctional composition. The inventors have found that the compositions and, in particular, surprisingly, but have discovered that certain multimodal composition, characterized by a relatively large number of branches in low-molecular-weight ethylene copolymer, are highly flexible and suitable for use in applications for films and pipes, as well as in applications for blow molding and injection molding.

Summary of invention

In one aspect the present invention relates to a multimodal polyethylene characterized by a density in the range from 0,940 to 0,965 g/cm3and the value of I21 in the range from 4 to 20 DG/min and containing the following ethylene copolymers:

low-molecular-weight ethylene copolymer having a mass-average molecular weight in the range from 5000 to 50,000 Amu Amu and characterized by short-chained index of branching in the range from 2.5 to 4.5; and

high molecular weight ethylene copolymer having a mass-average molecular weight in the range of 60000 u up to 800,000 Amu and characterized by short-chained index of branching in the range from 1 to 2.5.

Another aspect of the present invention relates to a multimodal polyethylene characterized by a density in the range from 0,940 to 0,965 g/cm3and the value of I21in the range from 4 to 20 DG/min and containing the following ethylene copolymers:

low-molecular-weight ethylene copolymer having a mass-average molecular weight in the range from 5000 to 50,000 Amu Amu; and

high molecular weight ethylene copolymer having a mass-average molecular weight in the range of 60000 u up to 800,000 Amu;

where is the mass fraction of high molecular weight ethylene copolymer in the calculation of gross multimodal composition is in the range from 0.3 to 0.7; and

where the ratio between the indices of the branches of low and high molecular weight ethylene copolymer is in the range from 1.2 to 6.0.

Data and other aspects the s of the invention can be combined with any number of implementation options, described in this document.

Brief description of drawings

Figure 1 shows a graphical representation of the results of GPC measurements and measurements of NMR for polymer fractions of the variants of realization of multimodal polymers according to the invention.

Figure 2 shows a graphical representation of the results of GPC measurements and measurements of NMR for polymer fractions of the variants of realization of multimodal polymers according to the invention.

Figure 3 shows a graphical representation of the results of GPC measurements and measurements of NMR for polymer fractions "comparative" polymer.

Figure 4 shows a graphical representation of the results of GPC measurements and measurements of NMR for polymer fractions "comparative" polymer.

Figure 5 shows a graphical representation of the results of GPC measurements and measurements of NMR for polymer fractions bimodal polymer Dow 2100.

Detailed description of the invention

In accordance with the usage in this document with reference to "groups" of elements from the Periodic table uses the "new" numbering scheme of the groups of the Periodic table, as in the CRC Handbook of Chemistry and Physics (David R. Lide ed., CRC Press 81st ed. 2000).

In accordance with the usage in this document "index short-chained time is of Evleri" or "branching index" means a number With 2-C5the alkyl groups of the side chains per 1000 carbon atoms of the main chain in the measured or mentioned polyethylene fractions. This value is determined according to the method described in this document in the section "Examples".

In accordance with the use herein of "multimodal polyethylene" refers to a polyethylene copolymer composition containing at least one identifiable low-molecular ethylene copolymer and one identifiable high-molecular ethylene copolymer, and the data for the ethylene copolymers can be identified using methods known at the present level of technology, such as analytical helpanimals chromatography ("GPC"), one embodiment of which is described herein in the Examples section. High - and low-molecular-weight ethylene copolymers can be identified by deconvolution techniques known state of the art for its suitability to highlight two polyethylene copolymers from a wide or having shoulders curve GPC multimodal polyethylene, and in yet another variant implementation of the GPC curve of the multimodal polyethylene of the invention can demonstrate the presence of distinct peaks with depression. In a preferred variant implementation of the multi the properties odel polyethylene, described in this document, essentially consists of one low and one high molecular weight ethylene copolymer, being, thus, "bimodal". "Multimodal polyethylene" do not limit the method of its production.

In accordance with the usage in this document, the ethylene copolymer is a polyolefin containing at least 60% of units derived from ethylene, based on the total weight of the polymer component. More preferably the ethylene copolymer in accordance with the use of this document contains the units derived from ethylene and α-olefins selected from the group consisting of C3-C12α-olefin and units derived from cyclic olefins, where the ethylene copolymer contains at least 50% or 80% (mass.) units derived from ethylene, and from the values greater than the detection threshold, up to 20% (mass.) units derived from α-olefins, preferably 1 to 10% (mass.) units derived from α-olefins. Most preferably α-olefin selected from the group consisting of C4-C8α-olefins.

In accordance with the usage in this document as "low-molecular-weight ethylene copolymer is an ethylene copolymer having a mass-average molecular weight in the range from 5000 to 50,000 Amu AEM., and more preferably from 5500 up to 40,000 Amu Amu In one embodiment, the implementation of low-molecular-weight ethylene copolymer is characterized by short-chained index of branching in the range from 2.5 to 4.5 and from 3 to 4 in the preferred implementation.

In accordance with the usage in this document, "high molecular weight ethylene copolymer is an ethylene copolymer having a mass-average molecular weight in the range of 60000 u up to 800,000 Amu, and more preferably from 65000 u up to 700,000 Amu In one embodiment, the implementation of high molecular weight ethylene copolymer is characterized by short-chained index of branching in the range from 1 to 2.5 and from 1.1 to 2.4 in the preferred implementation.

Mass fraction of high molecular weight ethylene copolymer in the calculation of gross multimodal composition can be at any level depending on the properties that are desirable for multimodal polyethylene; in one embodiment, the implementation of the mass fraction of high molecular weight ethylene copolymer is in the range from 0.3 to 0.7 (from 30 to 70% (mass.) when calculating the total weight of the multimodal polyethylene); and from 0.4 to 0.6 in yet another specific implementation and is in the range from 0.5 to 0.6 in yet another specific implementation.

In one the m variant of realization of multimodal polyethylene ratio between the indices of the branches of low and high molecular weight ethylene copolymer is in the range from 1.2 to 6.0 and from 1.5 to 5.0 in yet another variant implementation and from 1.8 to 4.5 in yet another embodiment, one implementation.

In one embodiment, the implementation of the multimodal polyethylene has a density (gradient density, ASTM D-792) in the range from 0,940 to 0,965 g/cm3and from 0,942 to 0,960 g/cm3in another implementation, where the desired density range may include any combination of any upper limit with any lower limit described herein. In addition, in one embodiment, the implementation of the multimodal polyethylene is characterized by a value of I21(I21as measured in accordance with ASTM-D-1238-F, 190°C/21,6 kg) in the range from 4 to 20 DG/min and from 5 to 16 DG/min in yet another variant implementation, and from 6 to 12 DG/min in yet another embodiment, one implementation where the desired range of values of I21may include any combination of any upper limit with any lower limit described herein. In yet another variant implementation of the multimodal polyethylene described herein, characterized by the value of I5(ASTM-D-1238-F, 190°C/5.0 kg) in the range from 0.2 to 0.5 DG/min and from 0.3 to 0.45 in yet another variant implementation, and from 0.3 to 0.4 in yet another implementation, where the desired range of values of I5may include any combination of any upper limit with any lower limit described in this document is NTE. Multimodal polyethylene described herein can be characterized by any combination of these signs.

In one embodiment, the implementation of the multimodal polyethylene is characterized by the ratio between the mass-average molecular weight and srednekamennogo molecular weight (molecular weight distribution) in the range from 30 to 100 and from 30 to 90 in yet another variant implementation, and from 35 to 80 in one other variant implementations where a desirable range may include any combination of any upper limit with any lower limit described herein. Preferably the molecular weight distribution obtained from analysis by GPC method described in this document.

Multimodal polyethylene is described in this document can be obtained by any suitable to use the method known state of the art, such as using physical mixing at least one high - and at least one low molecular weight ethylene copolymer, or methods of polymerization in place, the known state of the art, such as methods that use multi-stage reactors, or polymerization in place in one reactor. In one embodiment, the implementation of the multimodal polyethylene is produced in one gas is phase reactor with a fluidized bed continuous action.

In a particular implementation of the multimodal polyethylene, suitable for use in the invention are in one gas-phase reactor with a fluidized bed continuous action in the form obtained in place of the mixture, of at least one high molecular weight ethylene copolymer and at least one low molecular weight ethylene copolymer. In one or more embodiments of the polymerization system may include a reactor vessel, through the fluid communicated with one or more drain tanks, surge tanks and recirculation compressors. In one embodiment, the implementation of the reactor vessel includes a reaction zone inside the reactor vessel, through the fluid chamber connected with area decrease speed, usually located at the top of the reactor and having a conical geometry with increasing diameter. The reaction zone can include a layer of growing polymer particles, formed polymer particles and catalyst particles, expected under the action of a continuous stream of the polymerized and modifying gaseous components that are routed through the reaction zone in the form of supplied raw materials, complementary spending, and recirculation of the fluid.

The feed flow of the feedstock can be directed to Postup is giving in-line circulation to blowers, but you can also direct any point in a polymerization system including a fluidized bed reactor, in section extension or in-line circulation before or after the refrigerator, presents an alternative location of the feed flow of the feedstock. The term "feed flow of raw materials" in accordance with the usage in this document refers to material feedstock, either gas-phase or liquid-phase used in the method of polymerization to obtain the polymer product. For example, the feed flow of the feedstock can be any olefin monomer, including substituted and unsubstituted alkenes containing from two to 12 carbon atoms, such as ethylene, propylene, 1-butene, 1-penten, 4-methyl-1-penten, 1-hexene, 1-octene, 1-mission 1-dodecene, styrene and derivatives thereof. The feed flow of the feedstock also includes polifenoles gas, such as nitrogen and hydrogen. Supplied feedstock may flow into the reactor in several and different locations. For example, the monomers can be introduced into the polymerization zone in a variety of ways, including direct injection through the nozzle into the layer. The feed flow of the feedstock may optionally contain one or more directionspublic alkanes, which may be capable of condensation in PR is the process of polymerization in order to remove heat of reaction. Illustrative directionspanel alkanes include, but are not limited to: propane, butane, isobutane, pentane, isopentane, hexane, isomers and derivatives thereof. Such an operation state of the art called "operation mode condensation".

Fluidized bed has the General appearance of a dense mass of individually moving particles formed as a result of leakage of gas through the layer. The pressure drop across the layer is an amount equal to or slightly greater weight of the layer divided by the cross-sectional area. Thus, it depends on the geometry of the reactor. To save in the reaction zone a viable fluidized bed, the gas flow rate per unit cross section of the flux passing through the bed must exceed the minimum flow required for fluidization. Preferably the gas flow rate per cross sectional area of flow at least twice the minimum flow rate. Typically, the gas flow rate per cross sectional area of flow does not exceed 5.0 ft/sec, and usually will be sufficient value, not greater than 2.5 ft/sec.

In the General case, the ratio between the height and diameter of the reaction zone may range from 2:1 to 5:1. Needless to say that the range may vary, reaching larger or smaller ratios, and depends on the desired item is poizvodstvennaja power. The cross-sectional area reduction rate usually exceeds the cross-sectional area of the reaction zone with multiplicity in the range from 2 to 3.

Zone speed reduction has a larger inner diameter than the reaction zone. As the name suggests, the area reduction rate reduces the velocity of the gas due to the increased cross-sectional area. This reduction of the gas velocity leads to the downfall of trapped particles in the layer, making it possible leakage from the reactor mainly gas. The gas leaving the top of the reactor is a recirculating gas stream.

The recirculation flow komprimiert in the compressor and then perepuskat through a zone of heat transfer where heat assign to the return flow in the layer. Area of heat transfer is typically a heat exchanger, which may refer to the horizontal or vertical type. If you wish to stepwise reduce the temperature of the circulation gas flow can be used several heat exchangers. The compressor on the technological scheme can also be placed after the heat exchanger or in an intermediate point between multiple heat exchangers. After cooling the recycle stream back to the reactor. The cooled recycle stream receives heat of reaction generated in react and polymerization.

Preferably the recirculation flow back into the reactor and the fluidized bed through the gas distribution plate. On the intake hole in the reactor preferably install the vent gas. To prevent settling enabled polymer particles and agglomerating to obtain a solid mass and to prevent accumulation in the lower part of the reactor fluid and to increase the ease of transitions between those technological processes, in which the liquid is included in the circulating gas stream, and those that don't, and Vice versa. Illustrative baffle, suitable for use in the data view, described in documents US 4933415 and 6627713.

The activated composition predecessor, whether or not containing aluminiumalloy modifier (hereinafter in this document collectively called socialization) for use preferably stored in the tank of the catalyst in an atmosphere of a gas that is inert to the stored material, such as nitrogen or argon. Preferably the tank catalyst supply feeder, suitable for use in continuous flow of catalyst into the reactor. Illustrative tank catalyst shown and described, for example, in the document US 3779712. To transfer the catalyst layer pre is respectfully use gas, which is inert to the catalyst, such as nitrogen or argon. Preferably the carrier gas is the same as the gas used for the storage of catalysts under a layer of gas in the tank for the catalyst. In one implementation, the catalyst is a dry powder, and the feeder in the catalyst includes a rotating metering disk. In yet another variant implementation, the catalyst serves as a suspension in mineral oil or liquid hydrocarbon or mixture, as, for example, in the case of propane, butane, isopentane, hexane, heptane or octane. Illustrative tank catalyst shown and described in document WO 2004094489. The suspension of catalyst can be delivered into the reactor together with a fluid carrier, such as, for example, nitrogen or argon, or liquid such as, for example, isopentane or other3-C8alkane. During delivery to the reactor by line adding the supplied feedstock, the catalyst can be modified by using aluminiumtechnik modifiers, which are described in this document in a different location.

The catalyst was injected into the layer at the point, where is a good mixing with the polymer particles. For example, the catalyst is injected into the layer at a point above the distribution plate. Injection catalysis the Torah at the point above the distribution plate, allows to achieve satisfactory operation of a polymerization reactor with a fluidized bed. Injection of the catalyst into the area below the distribution plate, could initiate there the beginning of polymerization and, ultimately, lead to plugging of the distribution plate. Injection directly into the fluidized bed promotes uniform distribution of the catalyst throughout the bed and tends to prevent the formation of localized areas of high concentrations of catalyst, which may cause local overheating". In the reaction system you can also add connection activator and/or modifier (for example, aluminiumalloy connection, non-limiting illustrative example of which is triethylaluminium), either directly in the fluidized bed, or in the position of the flowsheet after the heat exchanger, in which case the modifier is served in the recirculation system of the dispenser.

The polymerization reaction is conducted essentially in the absence of catalyst poisons such as moisture, oxygen, carbon monoxide and acetylene. However, to change the structure of the polymer and its operational characteristics as the product in the reactor can CH the VA to add oxygen to very low concentrations. Oxygen can be added with a concentration in the range from 10 to 600 h/bn (R), and more preferably from 10 to 500 h/bn (R), in the calculation of the flow rate of the ethylene feedstock fed to the reactor.

In order to obtain the copolymer desired density ranges, with ethylene must be copolymerizable comonomers in an amount sufficient to achieve a level in the range from 0 to any value in the range from 5 to 10 wt.% the co monomer in the copolymer. The number of co monomer required to achieve this result will depend on the specific co monomer (comonomers), the activation temperature of the catalyst and its composition. To obtain the copolymer product of the desired density of the resin is necessary to control the ratio of co monomer and ethylene.

To determine the composition of the recirculation flow and composition of flows of raw materials, complementary spending may be used in the detector, which can be adjusted accordingly with the aim of keeping essentially stationary gas composition in the reaction zone. The detector may be a conventional detector, which determines the composition of the recycle stream with the aim of keeping the ratios between the components of the feed flow of the feedstock. is what equipment are commercially available from a wide range of sources. The detector can be placed in position to receive gas from point sampling, which is located between the zone of decreasing the speed and heat exchanger.

The performance of the polymer in the layer depends on the speed of injection of the catalyst and concentration of the monomer (monomers) in the reaction zone. Performance is usually controlled in the regulation of the speed of injection of the catalyst. Since any change in the speed of injection of the catalyst will change the reaction rate and, thus, the intensity with which the layer is formed warmth, approval of any changes to the rate of heat production achieved in the temperature control recirculation flow reactor. This provides a holding layer essentially constant temperature. Needless to say, suitable for use in the detection of any change of temperature in the layer is fully equipped with instrumentation as fluidized bed, and cooling system recirculation flow so that either the operator or conventional automatic control system was able to conduct proper regulation of the temperature of the recirculation stream.

For a given set of operating conditions of the fluidized bed stand with the society at a constant height in the selection process as the product of the layer with the rate of formation of particles of the polymer product. Since the intensity of heat generation is directly related with the rate of formation of product, the measurement result of a temperature increase of the fluid when passing through the reactor (the difference between the temperature of the fluid at the inlet and the temperature of the fluid at the outlet) at the constant speed of the fluid indicates the rate of formation of polymer particles, if the fluid at the inlet will not evaporating the liquid, or if it will be present in a negligibly small quantity.

After the release of particles of the polymer product from the case of gas-phase reactor with a fluidized bed, it is desirable and preferable to separate the fluid from the product and to return the fluid in the recirculation line. For carrying out this separation, there are many ways known state of the art. In one or more embodiments of fluid medium and the product leaving the reactor vessel and through the valve, which may be a ball valve, designed to create a minimum restriction to flow when opened, proceed to drain the tanks for the product. Before and after the drain tank product have normal valves. The valves allow the passage of the product in the surge tank for the product. Another preferably the system I product, which can be used in the alternative case is that described and claimed in the document US 4621952. In such a system is used, at least one (parallel) a couple of tanks including slop tank and the intermediate tank arranged in series and allow return of the separated gas phase from the top of the settling tank in position in the reactor near the top of the fluidized bed.

A reactor with a fluidized bed provide proper ventilation system, allowing you to ventilate layer during startup and shutdown. The reactor does not require mixing and/or obkalyvanija walls. The recirculation line and its elements must have a smooth surface and to be deprived of excessive interference, in order to avoid obstacles to the flow of recirculated fluid or trapped particles.

Conditions polymerizati vary depending on the monomers, catalysts and equipment availability. Specific conditions are known and can easily be developed by experts in the relevant field of technology. For example, temperature range from -10°C to 120°C., often from 15°C to 110°C. the Pressure may range from 0.1 bar to 100 bar, more preferably, for example, from 5 bar to 50 bar. Additional adolescents the activity in respect of polymerization can be found in the document US 6627713.

Multimodal polyethylene regardless of how it is produced, can be mixed with certain additives that state of the art it is known. Examples of commonly used additives, which can be introduced into the polymer, are antioxidants, ultraviolet absorbers of radiation, antistatic agents, pigments, dyes, nucleating fillers, additives reduce friction, flame retardants, plasticizers, processing AIDS, lubricants, stabilizers, dumpdevice, viscosity regulators and staplers, catalysts and accelerators, substances imparting stickiness, and substances that prevent adhesion. In addition to the fillers in the mixture may be present and additives in amounts in the range from 0.1 to 10 mass parts of additive per 100 mass parts of the polymer mixture.

In a particular implementation of the multimodal polyethylene is obtained by injection of ethylene and C3-C8α-olefins in contact with a composition of bimetallic catalyst containing a metallocene and nepetalactone catalyst. Metallocene well-known state of the art, and include ORGANOMETALLIC compound having at least one cyclopentadienyls ligand or ligands, isolabella the cyclopentadienyl, and metal from groups of 3-8 or lanthanides. The preferred metal is oceny include bis-cyclopentadienyls complexes of metals from groups 4, most preferably hafnium and zirconium, where the cyclopentadienyl selected from a cyclopentadienyl, indenyl, tetrahydroindene and substituted variants, most preferably asymmetrically substituted. The term "asymmetrically substituted" means that for each of cyclopentadienyls ligands or ligands, isolobal the cyclopentadienyl, there are different amounts, the type or the quantity and type of groups of deputies. In the most preferred embodiment, the implementation of metallocenes are asymmetrically substituted bis(cyclopentadienyl)zirconatetitanate or-dialkyl where groups of substituents selected from C1-C5Akilov.

In accordance with the usage in this document, the term "substituted" means that the group following the given term, in any position has at least one piece instead of one or more hydrogens (associated with carbon atom), and the fragments are selected from such groups as halogen radicals (especially Cl, F, Br), hydroxyl groups, carbonyl groups, carboxyl groups, amine groups, phosphine groups, alkoxy groups, phenyl groups, raftiline group1-C10alkyl group, a C2-C10alkeneamine group, and combinations thereof. Examples of the substituted Akilov and aryl which in include the following, but not limited to: acyl radicals, alkylamino radicals, alkoxy radicals, aryloxy radicals, alkylthio radicals, dialkylamino radicals, alkoxycarbonyl radicals, aryloxyalkyl radicals, carbamoyl radicals, alkyl - and dialkylanilines radicals, acyloxy radicals, acylamino radicals, arylamino-radicals, and combinations thereof.

What is meant by the term "nepetalactone catalyst, is any compound capable of polymerisation of olefins to obtain the ethylene copolymers described herein, non-limiting examples of which include catalysts based on chromium oxide chromocene catalysts, the catalysts of the Ziegler-Natta titanium-based, whether or not containing magnesium halides or derivatives alkylamine derived catalysts based on vanadium and Amin/kidnie coordination compounds of metals from groups 3-10. These types of compositions of catalysts well known state of the art for their ability to provide polyethylenes and other polyolefins.

Preferred embodiments of the compositions of bimetallic catalysts also include material carrier, such as an inorganic oxide or polymeric substances. Preferred media vklyuchayuthie silicon and aluminum oxide. Preferred embodiments of the compositions of the catalysts also include at least one activator. Activators are well known state of the art and include such compounds as alumoxane, aluminiumgie, alkylboron, alkylborane, airborne and arboreta compounds and mixtures thereof.

Multimodal polyethylene described herein are suitable for use in the manufacture of pipes, films, products, manufactured according to the method for blow molding, and products made by the method of centrifugal molding. The methods for the production of pipes made of polyethylene state of the art are well known. Can be used extruder any size, suitable for extruding a multimodal polyethylene in the manufacture of pipe, in one embodiment, the implementations use an extruder with smooth outlet or with a rifled zone diet, and suitable for use are either two-or single-screw extruders, and the ratio of length:diameter (L/D) is in the range from 1:20 to 1:100 in one implementation, preferably is in the range from 1:25 to 1:40, and the screw diameter of the extruder is of any desirable size in the range of, for example, from 30 mm to 500 mm, preferably 50 mm to 100 mm Extruders suitable for use in the project during extrusion described herein compositions for the manufacture of pipes, additionally describes, for example, Screw Extrusion, Science and Technology (James L. White and Helmut Potente, eds., Hanser, 2003). In one implementation options of the pipe made of the multimodal polyethylene described herein, characterized by the value of the parameter PENT (Pennsylvania tensile test when the incision on the edge) (F1473 ASTM D-01, 3.0 MPa and 80°C)equal to at least 150.

In one embodiment, the implementation of the multimodal polyethylene is formed into films, such as described in the work of Film Extrusion Manual, Process, Materials, Properties (TAPPI, 1992). To put it more specifically, the films are films made according to the method for blow molding, the method of obtaining them for the General case is described, for example, Film Extrusion Manual, Process, Materials, Properties, pp.16-29. For the manufacture of films can be used any extruder, suitable for extrusion of LLDPE (density in the range from 0.91 to 0,925 g/cm3) or HDPE (density, greater than 0,940 g/cm3operate under any conditions desired for polyethylene compositions described herein. Such extruders specialists in the relevant field of technology is known. Such extruders include those that are characterized by diameters of the screws in the range from 30 to 150 mm in one embodiment, implementation, and from 35 to 120 mm in yet another variant implementation will demonstrirujut the value of production in the range from 100 to 1500 lb/HR in one embodiment, implementation, and from 200 to 1000 lb/HR in yet another variant implementation. In one embodiment, the implementations use an extruder with a rifled power zone. The extruder can be characterized by the L/D ratio ranging from 80:1 to 2:1 in one embodiment, implementation, and from 60:1 to 6:1 in yet another variant implementation, and from 40:1 to 12:1 in yet another embodiment, one implementation and from 30:1 to 16:1 in yet another embodiment, one implementation.

Can be used extrusion head in order to obtain a single-layer or multilayer films. In one embodiment, the implementations use extrusion head to obtain a single film of a width in the range from 50 to 200 mm and extrusion head to obtain a single film of a width in the range from 90 to 160 mm in yet another variant implementation, and extrusion head to obtain a single film of a width in the range from 100 to 140 mm in yet another implementation, while the extrusion head is characterized by the nominal size of the slit of the extrusion head in the range from 0.6 to 3 mm in one embodiment, implementation, and from 0.8 to 2 mm in yet another variant implementation, and from 1 to 1.8 mm in yet another embodiment, one implementation where the desired extrusion head can describe any combination of any embodiments described herein. In a specific embodiment, the implementation of specific best throughput stated in this Doc is the COP, aged in 50-mm extruder with a rifled power zone at L/D 21:1 in a specific implementation.

The temperature zones of the extruder, on the liner and the adapter of the extruder is in the range from 150°C to 230°C. in one embodiment, implementation, and from 160°C to 210°C. in yet another variant implementation, and from 170°C to 190°C. in yet another embodiment, one implementation. The temperature in the extrusion head is in the range from 160°C to 250°C. in one embodiment, implementation, and from 170°C to 230°C. in yet another variant implementation, and from 180°C to 210°C in still another embodiment, one implementation.

In one implementation, a film made of a multimodal polyethylene with a thickness equal to at least 12 microns, characterized by a test result when dropping a pointed load equal to at least 200 grams; when this film is made when the degree of the bulge of 4:1 using a 50-mm extruder with a rifled power zone (L/D=18) c extrusion head is 100 mm and the slit of the extrusion head to 1.0 mm. In one embodiment, the implementation of the extruder extruder are Alpine or equivalent extruder Alpine.

Inflatable molding is a primary method of molding hollow plastic items such as bottles of soda water. The method includes clamping the edges softened polymer tubes, to the which you can either ekstradiroval, either re-heat, swelling of the polymer in the direction of the walls of the mold with a needle for razuki and cooling of the product by heat conduction or evaporation of volatile fluid in the container. There are three common types of blow molding: extrusion blow molding, injection blow molding and blow molding and extrusion. Extrusion blow molding is typically used for the manufacture of products having a mass greater than 12 ounces, such as containers for food, linen for Laundry or garbage. Injection blow molding is used to produce very accurate wall thickness, high neck and processing of polymers that cannot be ekstradiroval. Usual applications include pharmaceutical products and disposable bottles for alcoholic beverages, which weigh less than 12 ounces. The blow molding and hood used only for trudnoreshaemyh crystalline and kristallizuetsya polymers such as polypropylene and polyethylene terephthalate.

State of the art is also well known and centrifugal molding. Centrifugal molding is a method, also known as rotational molding or centrifugal casting, and it is used in the manufacture of pastoralisme plastic including large storage tanks, usually parts that are larger or more by volume than those made according to the method for blow molding. It includes placement of a powdered thermoplastic such as a polyolefin, in the form of heat forms in the furnace while rotating the mould around perpendicular axes.

Thus, the compositions and methods of the present invention in alternative cases can be described using any of the variants of implementation, described herein, or a combination of any of the variants of the implementation described in this document. The embodiments of the invention without intending to be limited by them can be better understood by reference to the following non-limiting examples.

EXAMPLES

The synthesis of the composition of bimetallic catalyst

To obtain polyethylenes of examples according to the invention used supported on a carrier composition of the bimetallic catalyst. Non-limiting implementations the examples according to the invention, presented in the table reflect separate experiments using the same catalyst under various conditions in the reactor. To obtain polyethylene this bimetallic catalyst was injected directly into the fluidized bed of the ri using purified nitrogen. The speed of injection of the catalyst was adjusted to bear approximately constant performance. In each experiment the catalyst contained silicon dioxide, digidrirovanny at 875°C, methylalumoxane, metallian (tetramethylcyclopentadienyl)(n-propylcyclopentanol)zirconiated and connection of a catalyst of Ziegler-Natta containing TiCl4and derived alkaline.

More specifically, the example method of bimetallic catalyst used in the examples according to the invention is as follows: can be used for the material of the carrier on the basis of silicon dioxide Davison SYLOPOL 955 Silica or Ineos ES757. Silica dehydration at a temperature of 875°C. After that, each sample of 500 grams of the corresponding digidratirovannogo silicon dioxide added to a 5-liter 3-necked round bottom flask, closed in the suit with the atmosphere of N2. Then the flask was added anhydrous hexane (2500 ml)to give a suspension of silicon dioxide/hexane. The suspension is heated to a temperature of approximately 54°C., while stirring and over a period of time of approximately 20 minutes, to a suspension add 380 grams of solution dibutylamine with a concentration of 15% (mass.). After that, the suspension allowed to stand for another 30 minutes. Bout the Nol (27.4 g) in a volumetric flask with a volume of 125 ml diluted to the mark with hexane. All 125 ml diluted solution of butanol are added dropwise into the flask containing the suspension and then the suspension for 30 minutes, maintained at a temperature of approximately 54°C., while stirring. The amount of butanol can be varied depending on the desired concentrations. The titanium tetrachloride (41,0 grams) in a volumetric flask with a volume of 125 ml diluted to the mark with hexane. After that, all 125 ml diluted solution of titanium tetrachloride are added dropwise into the flask containing the suspension. After adding a solution of suspension allow to settle for about 30 minutes at a temperature of approximately 54°C. Then the suspension allow to cool to ambient temperature.

After that, the sample in the form of digidratirovannogo silicon dioxide treated with titanium tetrachloride add connection metallocene catalyst. First in a new flask in a glove box with an atmosphere of N2add 673 grams of solution methylalumoxane (MAO) in toluene with a concentration of 30% (mass.). To a solution of MAO add approximately 13,72 grams of metallocene bis-n-butylcyclopentadienyl and the mixture is stirred until until all solids are dissolved. After that, the flask containing the previously obtained titanium containing the reaction suspension, the period of time approximately one hour, slowly add the mixture MAO/metallocene. For washing off the residual mixture MAO/metallocene remaining in the flask, the flask containing the reaction suspension, using toluene (50 ml). The molar ratio of Al/Zr (Al from MAO) may be in the range of approximately 90 to 110. The molar ratio of Ti/Zr is approximately 6. Then each of the resulting mixture, which included a sample of bimetallic catalyst, maintained at ambient temperature over a period of time lasting one hour. Then each mixture was dried using a rotary evaporator, followed by removal of a major part of hexanol when using vacuum pressure of 21 mm Hg at a temperature of 52°C. After that, the high-boiling toluene is removed using vacuum pressure of 28 mm Hg at 70°C. the Final dried bimetallic catalyst has the form of a free flowing solid phase brown. To obtain the polyethylene composition of each polymer sample used in a separate experiment by polymerization in the gas-phase reactor under the conditions identified in tables.

The polyethylene of comparative examples were also obtained when using nanesena what about the media bimetallic catalyst, received like the aforementioned bimetallic catalyst except that the metallocene compound was metallocene bis(n-butylcyclopentadienyl)zirconiated. Bimetallic catalyst and comparative multimodal polyethylene is obtained with its use, such as those described in document US 6878454. Various comparative examples presented in the tables reflect separate experiments using the same or similar catalyst under various conditions in the reactor.

Conditions for gas-phase polymerization

The polyethylene according to the invention" and "comparative" polyethylene is received in one gas-phase reactor with a fluidized bed continuous action. Fluidized bed reactor consisted of pellets of polyethylene. The reactor was passivatable using alkylamine, preferably trimethylaluminum. While obtaining the polymer in the reactor at the same time also added the same or similar alkylamine. During each experiment to the layer of the reactor in-line recirculation gas was injected gaseous streams supplied feedstock in the form of ethylene and hydrogen. Injection was carried out on technological scheme after the heat exchanger and compressor recirculation line. To the layer of the reactor has introduced idci comonomer 1-hexene. To the layer of the reactor in-line recirculation gas in gaseous or liquid form was added to the controller (for example, water, isopropyl alcohol and the like), in the case of its use, which was influenced by the ratio of the components of resin and has helped reduce fouling, especially with fouling bottom plate. For keeping the target conditions in the reactor, identified in each example, was controlled by individual threads alkylamine (trimethylaluminum, "TMA"), ethylene, hydrogen and co monomer is 1-hexene. Gas concentration was measured using a chromatograph operating in online mode. Other conditions are that are listed in the following tables.

The conditions of extrusion film

Samples of the resins in both tests was mixed with additives and molded to obtain a pellet and extrudible to obtain films with the use of the line Alpine 50 mm using an extruder with a rifled power zone Model Number HS 50 R/HM-AV 12-WS 12 when L/D 18:1, the slit of the extrusion head 1.0 mm, the extrusion head 100 mm Installation for temperature zones consisted of the following:

The cylinder 1, 395°F

The cylinder 2, 400°F

The adaptor unit 400°F

The lower adapter, 400°F

Vertical adapter, 410°F

The bottom of the extrusion head, 410°F

The middle of the extrusion head, 410°F

The top e is istruzioni head, 410°F

The PENT test

Obtained pellets of the resin, extruded to obtain records and tested PENT in accordance with the document F1473 ASTM D-01 in order to evaluate the operational characteristics of pipes made from polyethylene according to the invention. In particular, the resin was molded to obtain a pellet as indicated at the bottom of the tables. Test method Pent in accordance with the document F1473 ASTM D-01 (PENT) implemented at 3.0 MPa and 80°C; precision pressed and machined block of polyethylene sample was immersed in a fluid environment conducive to cracking under impact stresses, and placed under a tension load of 3.0 MPa. Temperature withstand constant at 80°C and measure the time to failure.

Table 2
Data analysis PENT
ExampleI21DensityPENT, 3.0 MPa
DG/ming/cm3F50, hours
Comparative4,2550,9476 74
Comparative4,2550,949529
Comparative4,270,945846
Comparative4,490,946344
Comparative4,8770,947518
Comparative4,8770,947712
Comparativea 4.90,946535
Comparative4,9490,946723
Comparative5,850,94813
Comparative6,1360,9498
According to the invention6,2196
According to the invention6,840,9479330
According to the inventiona 9.250,949940

Table 3
Conditions in the reactor from test 2
DescriptionAn example of the invention 3An example of the invention 4Comparative example
The temperature in the reactor°C959595
The pressure in the reactorpound/inch2(wt.)297297299
The partial pressure of ethylenepound/inch2(abs.)190184157
The ratio between costs hexene/ethylene The ratio lb/lb0,0300,0430,025
The molar ratio of hexene/ethyleneThe molar ratio0,0080,0220,0112
TMAppm96110100
H2About/ethyleneppmthe 11.611,4719
Isopentane% (mol.)5,54%are 5.36%0%
The hydrogen/ethyleneppm/% (mol.)11499107
Laboratory performancelb/lb3200440029002

Table 4
Results for manufacture of the Department of film of the test 2
DescriptionAn example of the invention(1)An example of the invention(1)Comparative example(2)
ASTM D1238 190/2,16 (I2)DG/min0,0770,1050,06
ASTM D1238 190/5,0 (I5)DG/min0,3310,3970,277
ASTM D1238 190/21,60 (I21)DG/minof 7.237,537,49
Density (3)g/ml0,9530,9500,949
PERFORMANCEkg/h4646454547,7
The proportion of the HEIGHT of the MUDDY STREAKS ON FILM(4)11,210,211,212,29,1
The AVERAGE THICKNESSmcm25,4a 12.725,4a 12.725,4
The DEGREE of the BULGE(5)44444
TEST IMPACT strength DROPPING a POINTED CARGO F50, ASTM D1709-01g203209224212206
TEST RASTER IN ELMENDORF, ASTM D-1922-00
In the longitudinal directiong/μm0,9 1,220,960,953,18
In the transverse directiong/μm10,612,6610,204,848,62
(1) the Granulated resin by setting the ZSK-30 mixed with the additive package consisting of 1500 ppm Irganox 1010, 1500 ppm Irgafos 168 and 1500 ppm ZnSt.
(2) Granulated resin by setting ZSK-57 was mixed with an additive package consisting of 200 ppm Irgafos 168, and 800 ppm Irganox 1010, 1000 ppm ZnSt and 200 ppm Carbowax.
(3) For forming plates used method of document ASTM D4703-00, while for the determination of density used method of document ASTM D-1505-98.
(4) the Proportion of height muddy streaks on the film, defined as a ratio between the height muddy streaks on the film for the greatest diameter of the sleeve and the diameter of the extrusion head.
(5) the Degree of the bulge, defined as the ratio between the largest diameter of the sleeve and the diameter of the extrusion head.

Table 5
Records of test 2
DescriptionAn example of the invention(1)Comparative example(3)
ASTM D1238 190/2,16 (I2)DG/min0,090,06
ASTM D1238 190/21,60 (I21)DG/min6,27,49
Density(4)g/cm30,9480,949
F1473 ASTM D-01 (PENT) (3.0 MPa/80°C)(5)1966,3
(1) Mixing by setting ZSK-30 with 1500 Irgafos-1010, 1500 Irganox-168.
(2) Mixing by setting ZSK-30 with 1500 Irgafos-1010, 1500 Irganox-168, 1000 ppm ZnSt.
(3) the Product Prodex mixed with 1000 ppm Irganox 1010, 2000 ppm Irgafos-168.
(4) For forming plates used method of document ASTM D1928-00, while for the determination of density used method of document ASTM D-792.
(5) the Test was carried out at 3.0 MPa and 80°C.

The branching index

The inventors have found that a multimodal polyethylene, characterizability index of branching, have properties that make polyethylene is highly flexible and suitable for use in the film, pipe products is made by means of the centrifugal molding and blow molding. In particular, it was found that desirable are multimodal polyethylene containing at least one relatively low molecular weight fraction and a relatively high molecular weight fraction, each of which is characterized by a certain index of branching. The following table 6 describes the characteristics for resin according to the invention, comparative resin (described earlier) and "comparative" resin Dow 2100. Resin Dow 2100 is a bimodal high density polyethylene (0,949 g/cm3), characterized by the value of I219 DG/min and obtained in tandem reactors. The described implementations are assumed as non-limiting examples of such multimodal polyethylene can be obtained.

The branching index represents the ratio in number of branches per 1000 carbon atoms in the main polymer chain. In the present invention, as shown in table 6, it is defined by dividing one sample (according to the method of fractionation by selective solvent) for five to seven fractions with the hypoxia molecular weight and after that, measurement of branching for each molecular weight by the method of NMR. For a given sample, this results in the dependence of the number of branches per 1000 carbon atoms from the molecular weight. Then, for each of the ethylene copolymer can be estimated frequency of branching. "Branching index"described in this document represents the number estimated by any method known state of the art, preferably described, within ±15% or less.

More specifically, the index of branching was determined by the method adapted from the methodology of the workW. Holtrup, 178 Makromol. Chem. 2335 (1977). In order to obtain fractions characterized by a narrow molecular weight distribution, were consistent fractionation of a solution by dynamic method of direct extraction in accordance with the methodology of the author Holtrup. In a typical example, in the reactor for sample volume of 180 ml was placed approximately 1 g of the polymer sample and at 130°C in the variation of volumetric ratios in mixtures of xylene/etilenglikolevye ether (solvent/herstorical") received 8 fractions. Used a mixture containing 65, 60, 55, 50, 43, 40 and 37% of the solvent. Solvent and herstorical stabilized using approximately 6 g of 2,6-di-tert-butyl-4-IU is kilfenora on 4 l of solvent. The fractions obtained were besieged with excess acetone, filtered and dried under vacuum. After this branching was measured by the method1H NMR. The solvent in each case was well mixed with the polymer at 130°C, then cooled, and then again heated, and then centrifuged to separate the insoluble fraction (fractions), followed by separating the precipitate, and this fraction is consistently re-solubilizers in solvents containing high amount of stronger diluent, in this case, xylene. This technique can be implemented for other multimodal polyethylenes obtained by any of the methods outlined previously, when changes in mixtures of solvents, which is determined by a specialist in its respective field of technology based on the properties of polyethylene subjected to the test.

GPC. The curves shown on the drawings, the values of Mw/Mn, Mw (mass-average molecular weight) and Mn (srednekislye molecular weight) and % VM-fraction of the ethylene copolymer and the like were obtained from measurements by the method of gel chromatography using columns with crosslinked polystyrene; sequence pore size: 1 column less than 1000 Å, 3 columns with a mixture of 5 x 10(7) Å; the solvent is 1,2,4-trichlorobenzene at 145°C With a detection rate of prelamin is. Data on GPC in the deconvolution using "models Wesslau" was divided into the contributions of high - and low-molecular weight ethylene copolymers, where a member of β for low molecular weight peak was limited to a value of 1.4, as described in the work of E. Broyer & R. F. Abbott,Analysis of molecular weight distribution using multiethylene copolymer modelsACS Symp. Ser. (1982), 197 (Comput. Appl. Appl. Polym. Sci.), 45-64.

Table 6
Characteristics of branches
PolyethyleneThe branching index for NM-factionThe branching index for VM-factionThe ratio NM/VM
According to the invention3,4-3,81,6-1,92-2,1
Comparative5-7,61-1,25-6,2
Dow 21002-2,32,2-3,30,61-1,04

1. Multimodal polyethylene, suitable for application in the field of both films and pipes, with this multimodal polyethylene is characterized by a density in the range from 0,940 to 0,965 g/cm3and in the guise of melt index I 21in the range from 4 to 20 DG/min and containing the following ethylene copolymers:
(a) a low molecular weight ethylene copolymer having a mass-average molecular weight in the range from 5000 to 50,000 Amu Amu and characterized by short-chained index of branching in the range from 2.5 to 4.5; and
(b) high molecular weight ethylene copolymer having a mass-average molecular weight in the range of 60000 u up to 800,000 Amu and characterized by short-chained index of branching in the range from 1 to 2.5.

2. Multimodal polyethylene according to claim 1, where the ratio between the short-chained index of the branching fractions of low molecular weight ethylene copolymer and short-chained index of the branching fractions of high molecular weight ethylene copolymer is in the range from 1.5 to 4.5.

3. Multimodal polyethylene according to claim 1, where the low molecular weight ethylene copolymer is characterized by short-chained index of branching in the range from 3 to 4.

4. Multimodal polyethylene according to claim 1, where the molecular weight distribution of the polyethylene is in the range from 30 to 100.

5. Multimodal polyethylene according to claim 1, where the mass fraction of high molecular weight ethylene copolymer, based on total composition of multimodal polyethylene is in the range from 0.3 to 0.7.

6. Multimodal polyethylene according to claim 1, where al is flax receive one gas-phase reactor with a fluidized bed continuous action.

7. Multimodal polyethylene according to claim 1, where the polyethylene is obtained by injection of ethylene and3-C8α-olefins in contact with a composition of bimetallic catalyst containing a metallocene and nepetalactone catalyst.

8. Multimodal polyethylene according to claim 7, where metallocene is a bis-cyclopentadienyls complex of a metal of group 4; where cyclopentadienyl selected from the group consisting of cyclopentadienyl, indenyl, tetrahydroindene and their substituted versions.

9. The multimodal polyethylene of claim 8, where metallocene is asymmetrically substituted.

10. Multimodal polyethylene according to claim 1, where the film made of the multimodal polyethylene with a thickness equal to at least 12 microns, characterized by a test result when dropping a pointed load equal to at least 200 g; the film is made in the operating conditions of the extruder using a line 50 mm using an extruder with a rifled power zone at L/D 18:1, the slit of the extrusion head 1.0 mm, the extrusion head 100 mm

11. Multimodal polyethylene according to claim 1, where the pipe made of the multimodal polyethylene, characterized by the value of the parameter PENT (derived in Pennsylvania tension test when the incision on the edge; ASTM D F 1473-01, 3.0 MPa and 80°C), is equal to, less is th least 150.

12. Multimodal polyethylene according to claim 1, essentially consisting of one high molecular weight fraction and one low molecular weight fraction.

13. Multimodal polyethylene, suitable for application in the field of both films and pipes, with this multimodal polyethylene is characterized by a density in the range from 0,940 to 0,965 g/cm3and the value of the melt index I21in the range from 4 to 20 DG/min and containing the following ethylene copolymers:
(a) a low molecular weight ethylene copolymer having a mass-average molecular weight in the range from 5000 to 50,000 Amu Amu; and
(b) high molecular weight ethylene copolymer having a mass-average molecular weight in the range of 60000 u up to 800,000 Amu;
where is the mass fraction of high molecular weight ethylene copolymer in the calculation of gross multimodal composition is in the range from 0.3 to 0.7; and
where the ratio between the indices of the branches of low and high molecular weight ethylene copolymer is in the range from 1.2 to 6.0.

14. Multimodal polyethylene according to item 13, where the ratio between the indices of the branches of low and high molecular weight ethylene copolymer is in the range from 1.5 to 5.0.

15. Multimodal polyethylene 14, where the ratio between the indices of the branches of low and high molecular weight ethylene copolymere which is in the range from 1.8 to 4.5.

16. Multimodal polyethylene according to any one of p-15, where polyethylene is produced in one gas-phase reactor with a fluidized bed continuous action.

17. Multimodal polyethylene according to any one of p-15, where the polyethylene is obtained by injection of ethylene and3-C8α-olefins in contact with a composition of bimetallic catalyst containing a metallocene and nepetalactone catalyst.

18. Multimodal polyethylene 17, where metallocene is a bis-cyclopentadienyls complex of a metal of group 4; where cyclopentadienyl selected from the group consisting of cyclopentadienyl, indenyl, tetrahydroindene and their substituted versions.

19. Multimodal polyethylene 17, where metallocene is asymmetrically substituted.

20. Multimodal polyethylene according to item 13, where the pipe is made of multimodeling polyethylene, characterized by the value of the parameter PENT (derived in Pennsylvania tension test when the incision on the edge; F1473 ASTM D-01, 3.0 MPa and 80°C)equal to at least 150.

21. Multimodal polyethylene according to § 15 essentially consists of one high molecular weight fraction and one low molecular weight fraction.

22. Manufactured by centrifugal molding product obtained from the multimodal polyethylene according to any one of claims 1 to 9, 13-19.

23. And is prepared according to the method for blow molding product, obtained from the multimodal polyethylene according to any one of claims 1 to 9, 13-19.



 

Same patents:

FIELD: process engineering.

SUBSTANCE: invention relates to production of microporous polyethylene membranes to be used in storage battery separators. Membrane is produced by mixing polyethylene resin melt and membrane-forming solvent to prepare solutions of polyethylene resin A with concentration of 25-50% by wt and with that B of 10-30% by wt. Note here that concentration of A exceeds that of B. Melts are simultaneously extruded through spinneret, extrudate is cooled to produce gel-like sheet wherein resins A and B are laminated and membrane-forming solvent is removed. Solutions of resins A and B may be extruded through separate spinnerets with removal of membrane-forming solvent from obtained gel-like sheets A and B, formation of microporous polyethylene membranes A and B and their lamination in controlling mean diametre of pores over membrane depth.

EFFECT: microporous polyethylene membranes with balances mechanical properties, permeability, anti-shrinking properties, resistance to compression, absorption capacity, and pore mean diametre varying over membrane depth.

5 cl, 2 tbl, 16 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a biodegradable thermoplastic composition used in making films and various hot-moulded articles in form of consumer packaging. The composition contains polyethylene, a copolymer of ethylene and vinylacetate, starch, nonionic surfactant and schungite.

EFFECT: composition has good rheological characteristics and is biodegradable under the effect of light, moisture and soil microflora.

2 tbl, 4 ex

FIELD: chemistry.

SUBSTANCE: composition contains crystalline propyelen polymer, elastomeric copolymer of ethylene and propylene and polyethylene. When combined with components with certain values of polydispersity index and characteristic viscosity in given ratios, the composition exhibits high hardness, impact resistance and resistance to bleaching under loading. The composition has flexural modulus higher than 1300 MPa, resistance to bleaching during impact corresponding to diametre of the bleaching area not greater than 1.7 cm, caused by a die falling from a height of 76 cm and diametre of the bleaching area not greater than 1.2 cm, caused by a die falling from a height of 20 cm, and Izod impact resistance at 23°C greater than 14 kJ/m2 and at least equal to 6.5 kJ/m2 at -20°C.

EFFECT: composition has good balance of mechanical properties, is suitable for making articles through pressure casting, such as casings of batteries and consumer goods, and during hot shaping processes.

2 cl, 4 tbl, 3 ex

FIELD: chemistry.

SUBSTANCE: composition contains polyethylene production and/or household wastes, beet pulp and bentonite as a processing additive.

EFFECT: disclosed composition has rheological characteristics which meet requirements for polymeric materials for their possible processing on conventional equipment, as well as required operational characteristics, including biodegradability.

4 ex, 2 tbl

FIELD: chemistry.

SUBSTANCE: composition with multimodal distribution of molecular weight has density between 0.94 and 0.95 g/cm3 at 23°C and melt flow index (MFI190/5) between 1.2-2.1 dg/min in accordance with ISO 1133. The composition contains 45-55 wt % low molecular weight homopolymer A of ethylene, 30-40 wt % high molecular weight copolymer B of ethylene and another olefin containing 4-8 carbon atoms, and 10-20 wt % ultrahigh molecular weight copolymer C of ethylene and another olefin containing 4-8 carbon atoms. The composition has high processibillity and resistance to mechanical loads and breaking, especially at temperatures below 0°C.

EFFECT: flawless coating for steel pips has mechanical strength properties combined with high hardness.

10 cl, 1 tbl, 1 ex

FIELD: process engineering.

SUBSTANCE: invention relates to multilayer microporous polyethylene membrane and storage battery made thereof. Proposed membrane has at least two microporous layers. One layer (a) of polyethylene resin A contains high-density polyethylene A with 0.2 and more end vinyl groups per 10 000 carbon atoms defined by IR-spectroscopy. Second microporous layer (b) of polyethylene resin B contains high-density polyethylene A with smaller than 0.2 end vinyl groups per 10 000 carbon atoms defined by IR-spectroscopy. Said membrane is produced by two methods. First method comprises simultaneous extrusion of solutions of polyethylene resins A and B through spinneret, cooling of extrudate, removing of solvent and laminating. Second method comprises extrusion of said solutions through different spinnerets. Said membrane is used to produce storage battery separator.

EFFECT: well-balanced characteristics of melting and cutting-off, good forming property of film and separator and anti-oxidation properties.

4 cl, 1 tbl, 3 ex

FIELD: chemistry.

SUBSTANCE: moulding method involves heating thermoplastic material higher than melting point, forcing the obtained melt through a die at 10-100°C higher than melting point of the thermoplastic material and cooling the product to temperature lower than melting point. The composition of thermoplastic material includes a thermoplastic polymer and a complex additive for improving moulding. The complex additive used is a reactive composition containing at least one polyether polyol and at least one thickening component selected from a group comprising polybasic organic acids, anhydrides of polybasic organic acids, fatty acids containing 8-18 carbon atoms, as well as mixtures thereof.

EFFECT: method cuts on induction time, increases rate of flawless moulding thermoplastic material, reduces power consumption and moulding temperature, lowers pressure in the equipment when moulding high molecular weight polymers, simplifies and lowers the cost of moulding articles from thermoplastic polymer materials.

12 cl, 11 dwg, 14 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing composite nanomaterials for antifrictional purposes. The materials can be used in systems working under high deformation loads and in friction assemblies. The method involves mechanical activation of powder filler in form of sheet silicate in a ball mill in high-speed mode. Further, the powder filler is then mixed with powdered ultra-high molecular weight polyethylene for 10-60 minutes in a high-energy mill combined with mechanical activation.

EFFECT: obtained mixture is starting material from which articles with improved tribological characteristics, high mechanical strength and elasticity are moulded.

2 cl, 9 dwg, 2 tbl, 1 ex

FIELD: chemistry.

SUBSTANCE: invention relates to polymer materials meant for making articles via rotational moulding. The rotational moulding polymer material contains particles of a thermoplastic polymer or a mixture of thermoplastic polymers on whose surface there are silicon oxide particles whose size ranges between 1 and 1000 nm in amount of 0.001-0.1% of the total weight of the polymer material.

EFFECT: obtained material cuts on moulding time without considerable overheating of the molten mass with simultaneous removal of bubbles, as well as high mechanical strength of the articles.

5 cl, 36 dwg, 7 ex

FIELD: chemistry.

SUBSTANCE: rubber mix is prepared from butadiene-nitrile rubber BNKS-18 AMN with addition of powdered ultra-high-molecular-weight polyethylene (UHMWPE) in the following ratio of components, wt %: BNKS-18 AMN butadiene-nitrile rubber 40-46.3; SKMS-10 RKP rubber 19.0; stearine 0.54; zinc white BT-M 1.63; sulphur 0.54; diaphene FP 0.54; paraffin 0.54; dibutylphthalate 3.2; technical rubber P-701 25-31.3; UHMWPE 1.63; sulfenamide T 0.54; thiuram 0.54.

EFFECT: high oil and moisture resistance and frost resistance of cushion pads.

1 tbl

FIELD: chemistry.

SUBSTANCE: air-permeable material contains a woven layer on which there is a polymer film layer. The polymer film layer contains a polymer composition and filler, where the air-permeable material was exposed to physical action in order to make the polymer layer mircroporous, so that SPVP of the air-permeable material is greater than 50 g/m2·24 h, and where the air-permeable material has primary dimension on the length and primary dimension on the width before the said physical action and secondary dimension on the length and secondary dimension on the width after the said physical action, where the secondary dimension on the length is not more than 2% greater than the primary dimension on the length and the secondary dimension on the width is not more than 2% greater than the primary dimension on the width. The invention also discloses methods of producing air-permeable material with said properties.

EFFECT: design of air-permeable material with improved properties.

49 cl, 11 dwg, 3 ex

FIELD: chemistry.

SUBSTANCE: present invention relates to a method of modifying a biodegradable polymer or copolymer. Described is a method of modifying a polymer or copolymer, having the structure of one or more repeating units (1), where n is an integer, m is an integer between 0 and 6, and R is selected from hydrogen, substituted or unsubstituted C1-C20 alkyl, C3-C20 cycloalkyl, C6-C20 aryl, C7-C20 aralkyl and C7-C20 alkaryl, where said groups may include straight or branched alkyl fragments; optionally one or more substitutes are selected from a group comprising hydroxyl groups, alkoxy groups, straight or branched alk(en)yl, aryloxy, halogen, carboxylic acid, ester, carboxy, nitrile and amido, involving bringing the polymer or copolymer into contact with a cyclic organic peroxide under conditions where at least a certain amount of the said peroxide decomposes. The invention also describes a modified polymer or copolymer obtained using said method.

EFFECT: obtaining a (co)polymer characterised by high degree of branching without formation of gel.

7 cl, 4 ex, 8 tbl, 3 dwg

FIELD: chemistry.

SUBSTANCE: method involves drawing an polyethylene terephthalate article in an adsorption-active liquid medium containing modifying additives, and drying the article in air until complete removal of the solvent. The modifying additive is a biocidal preparation or antipyrene. The polymer article with an extended shape used can be a fibre, a film, a tape, a tube or a rod.

EFFECT: invention simplifies the technology of making polyethylene terephthalate articles with good biocidal properties and low combustibility compared to existing articles.

20 cl, 2 dwg

FIELD: chemistry.

SUBSTANCE: article has a fluorescent coloured sublayer film and a fluorescent coloured film of an overlay layer on top of the fluorescent coloured sublayer film. The fluorescent coloured sublayer film has a first fluorescent dye in the polymer matrix of the sublayer. The fluorescent coloured film of the overlay layer has a second fluorescent dye in the polymer matrix of the overlay layer. The second fluorescent dye in the film of the overlay layer at least partially blocks light in a first wavelength range, while passing light in a second wavelength range in amount which is sufficient for fluorescence of the first fluorescent dye.

EFFECT: invention ensures design of a fluorescent article with improved operational characteristics.

25 cl, 8 dwg, 3 tbl, 3 ex

FIELD: process engineering.

SUBSTANCE: this invention relates to porous films used as filtration membranes. Proposed film comprise poly(vinylidene fluoride) as the main component and polyethylene glycol as hydrophilic component. Degree of crystallinity of poly(vinylidene fluoride) polymer makes 50% or higher, but not exceeds 90%, while product of degree of crystallinity of poly(vinylidene fluoride) polymer by specific area of film surface makes 300 (%·m2/g) or higher, but not exceeds 2000 (%·m2/g). Porous film is produced by extruding film-forming solution from injection orifice. Said solution comprises hydrophobic and hydrophilic components and common solvent. Film-forming solution is hardened.

EFFECT: improved water permeability and resistance to effects caused by porous poly(vinylidene fluoride) film reagents.

12 cl, 1 tbl, 11 ex

FIELD: chemistry.

SUBSTANCE: invention relates to production of shrinkable polymer labels, particularly to preparation of a film composition. The composition contains (a) a high-impact polystyrene component (HIPS) with a block-copolymer grafted to the polystyrene, (b) 10-50 wt % general purpose polystyrene (GPPS) and (c) approximately 2-80 wt % styrene block-copolymer. Component (a) contains a grafted rubber component which is a styrene block-copolymer and a rubber-like diene with conjugated double bonds from 1 to 7 wt % of the weight of the HIPS; less than 10 wt % concentration of gel, defined by extraction of the methylethylketone/methanol mixture. The average particle size of the rubber is less than 1 mcm and 0.01 mcm or more. Approximately 40-90 vol % of the rubber particles have diametre approximately less than 0.4 mcm and approximately 10-60 vol % of the rubber particles have diametre of approximately 0.4-2.5 mcm. Most of the rubber particles have a nucleus-shell morphology and said particles are in concentration of 10-70 wt % of the total weight of the polymer composition, and 1-5 wt % of the rubber-like diene of the total weight of the polymer composition.

EFFECT: film made from said composition has ratio of directed length to non-directed length in the direction of the greatest drawing at least equal to 3:1 and enable increase in size by 20% in the direction of less stretching at 110°C.

10 cl, 3 tbl, 7 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing electroconductive gas-sensitive material for a nitrogen dioxide sensor. The method of producing gas-sensitive material involves preparation of a film-forming solution from polyacrylonitrile and copper (II) chloride CuCl in dimethylformamide, which is deposited through centrifuging onto a substrate made from quartz glass and undergoes drying and infrared annealing successively in two steps: on air at temperature 150°C for 15 minutes and at 200°C for 15 minutes; and in an argon atmosphere at T=150°C, 200°C for 15 minutes; and then at T=500-800°C for 5 minutes.

EFFECT: obtaining gas-sensitive material which is sensitive to nitrogen dioxide with semiconductor properties from material which has dielectric properties using infrared annealing.

3 tbl, 2 dwg

FIELD: process engineering.

SUBSTANCE: invention relates to multilayer metallised biaxially-oriented polypropylene films used for food packing and to method of their production. Said film comprises main layer A made from crystalline home- or copolymers of propylene comprising bonds C2-C10 of alpha-olefine, one top layer B made from propylene copolymer containing 3 to 6 wt % of the bonds of linear C4-C10-1-alkene, and metal layer M applied on the surface of top layer B. Propylene copolymer of layer B has fraction soluble in xylene at 23°C, less than 4.0 wt %, Vick softening point above 135°C indenter depth in Vick test smaller than or equal to 0.05 mm at 120°C. Method of film production comprises co-extrusion of layers A and B, biaxial orienting of co-extruded layer A and B, treatment of top layer B surface and metal deposition on said layer.

EFFECT: multilayer metallised biaxially-oriented polypropylene films with high oxygen and steam barrier properties.

FIELD: process engineering.

SUBSTANCE: proposed method allows producing extruded one- or multilayer polymer film 8 with a structure produced therein at least partially. Said film is produced by stamping. Finished film 8 features thickness of 1 to 1500 mcm, preferably, of 30 to 300 mcm. Structure features depth of 1 to 1000 mcm, preferably of 5-300 mcm, particularly preferably, of 10-20 mcm. Width of structure groove 9 makes 1-1000 mcm, preferably, 10-500 mcm, particularly preferably, 40-80 mcm. Distance between structure grooves 9 makes 1-1000 mcm, preferably, 100-500 mcm, particularly preferably, 200-300 mcm. Note here that produced may be linear or linear-crossed structure with grooves 9. Said film is intended for packing and may be produced as described in invention claims. Said polymer film 8 is jointed with other layers of package materials 6, 7, and polymer film 8 is supplemented by other layers of package materials 6, 7, and package breakage pattern is defined by polymer film 8.

EFFECT: polymer film that allows ease of marking, breaking at preferable direction.

15 cl, 5 dwg

FIELD: chemistry.

SUBSTANCE: thermoplastic material, having a polyethylene matrix which contains 1-70 pts. wt polypropylene per 100 pts. wt polyethylene matrix, is used to make medical and hygienic films. After heating, said material is passed through a pressing zone between cooled rollers, where the initial film-type linen is heated to molten state of the material of the polyethylene matrix but not up to temperature of molten polypropylene.

EFFECT: inproved operational characteristics of film-type linen including for films with thickness equal to less than 20 mcm.

25 cl, 1 dwg, 6 tbl, 2 ex

FIELD: chemistry.

SUBSTANCE: present invention relates to methods of polymerising olefins in the presence of hybrid catalysts, as well as methods of regulating relative activity of active centres of such hybrid catalysts. Described is a method of producing olefin polymers, involving polymerisation of at least one α-olefin in the presence of a catalyst system to obtain a polymer containing at least a high molecular weight polymer component and a low molecular weight polymer component, in the presence of water in amount of 2-100 pts. mol per mln or carbon dioxide in amount of 2-100 pts. mol per mln, in each case in terms of the entire reaction mixture, where the catalyst system includes at least two different catalyst components and at least one catalyst component which is a transition metal complex selected from Fe, Co, Ni, Pd and Pt, and at least one ligand of general formula (IVe): where each E1D atom denotes nitrogen, each E2D atom denotes carbon, R19D and R25D each independently denotes arylalkyl with 1-10 carbon atoms in the alkyl radical and 6-20 carbon atoms in the aryl radical, where organic radicals R19D and R25D may also be substituted with halogens or a group containing O, R20D-R24D each independently denotes hydrogen, C1-C10-alkyl, 5-7-member cycloalkyl or cycloalkenyl, C2-C22-alkenyl, C6-C40-aryl, arylalkyl with 1-10 carbon atoms in the alkyl radical and 6-20 carbon atoms in the aryl radical, -NR26D2> -SiR26D3, where organic radicals R20D-R25D may also be substituted with halogens and/or two geminal or vinyl radicals, R20D-R25D may also bond to form a 5-, 6- or 7-member ring, radicals R26D each independently denotes hydrogen, C1-C20-alkyl, a 5-7-member cycloalkyl or cycloalkenyl, , C2-C20-alkenyl, C6-C40-aryl or arylalkyl with 1-10 carbon atoms in the alkyl radical and 6-20 carbon atoms in the aryl radical, and two R26D radicals may also bond to form a 5- or 6-member ring, u equals 1, each index v equals 1, where the bond between the carbon, which is bonded with one radical, and the neighbouring element E1D is a double bond. The invention also describes a method of regulating the ratio of the high molecular weight polymer component to the low molecular weight polymer component in the said method, which involves polymerisation of at least one α-olefin at temperature 50-130°Cand pressure 0.1-150 MPa in the presence of a catalyst system which includes at least two different catalyst components, in which carbon dioxide is used in amount of 2-100 pts. mol per mln, in order to reduce the amount of the high molecular weight polymer component or water in amount of 2-100 pts. mol per million in order to reduce the amount the low molecular weight polymer component, where the amount in pts. mol per mln is calculated based on the entire reaction mixture in each case. The invention describes use of carbon dioxide in the said method in order to reduce the ratio of the high molecular weight component to the low molecular weight component in the olefin polymer during polymerisation. The invention also describes use of water in the said method in order to increase the ratio of the high molecular weight component to the low molecular weight component in the olefin polymer during polymerisation.

EFFECT: regulation of the ratio of polymer components formed on active centres of catalyst components.

17 cl, 2 tbl, 7 ex

Up!