Polyethylene tubes

FIELD: chemistry.

SUBSTANCE: method involves preparation of a mixture containing 5-50 wt % filler and 95-50 wt % low density polyethylene and 0-3 wt % of one or more stabilisers.The obtained mixture and high density polyethylene containing at least one low-molecular component which is a copolymer of ethylene and C3-C10 α-olefin are mixed in a molten mass until the end product is obtained at drop point of 165-185°C. The obtained composition for making tubes contains 1-20 wt % filler in terms of mass of the composition.

EFFECT: composition has better balance of properties and can be extruded with sufficiently high efficiency at optimal low melt temperature.

19 cl, 3 tbl, 7 ex

 

The present invention relates to a plastic pipe, and more particularly to polyethylene compositions suitable for production of high-strength pipes with improved extraterrest, and to methods of producing such tubes.

The LEVEL of TECHNOLOGY

Pipes made of polyethylene of high density, well-known state of the art. Tubes are produced by extrusion from the melt of polyethylene mixed with a filler material such as carbon black, and pipes receive, therefore, at the stage of the melt with the desired inner and outer diameters and wall thickness, which determines the extrusion head, which is used to produce pipes. One problem with this technique is that pipe before cooling may SAG, which thus results in low-quality pipes. This problem can be partially reduced by lowering the temperature of the extruder and, thus, lowering the temperature of the extrudate. However, this may result in insufficient generation or specific performance extrudate and, thus, increase the cost of production of the pipe. Furthermore, increasing productivity while lowering the temperature of the extruder may be undesirable way will increase the back pressure in the extruder. This issue should also be taken into account for polyethylene resins used for the production of pipes.

Despite the fact that in document US 6878454 recently been described polyethylene of high density, which can be successfully ekstradiroval for the production of films, characterized by a low number of gelation, it does not solve the problem of extruding compositions suitable for the manufacture of tubes, which contain a relatively large amount of filling material, which affects the properties of the composition, and the presence of other distinctive properties, such as the need for high resistance to the rapid spread of the crack.

Need is high-density polyethylene, which, for its Association with the desired amount of filler can be ekstradiroval at the desired low temperature of the melt, to prevent sagging, but can at the same time to ekstradiroval at a sufficiently high performance. The inventors have solved this problem by using improved high density polyethylene, detecting the presence of a superior balance of properties.

The INVENTION

One aspect of the present invention relates to compositions tubes containing in one embodiment, the implementation of from 80 to 99 wt.% polyethylene high the th density per weight of the composition and from 1 to 20 wt.% filler based on the weight of the composition; while polyethylene has a density of from 0,940 to 0,980 g/cm3and I21from 2 to 18 DG/min; characterized in that the composition of the pipe extruded at melt temperature Tmthat satisfies the following relationship:

Tm<230-3,3(I21),

where the composition is also extruded with specific performance exceeding 1,38 kg/h/rpm to get the pipe.

In another aspect of the present invention in one implementation relates to a method for producing a pipe, including:

(a) obtaining a mixture containing from 5 to 50 wt.% filler, from 95 to 50 wt.% low density polyethylene and from 0 to 3 wt.% one or more stabilizers;

(b) mixing in the melt mixture and high density polyethylene, having a density of from 0,940 to 0,980 g/cm3and I21from 2 to 18 DG/min to the target temperature dropping from 165 to 185°C with the formation of the composition of the pipe, while mixing in the melt is carried out so that the composition of the pipe contains from 1 to 20 wt.% filler based on the weight of the composition of the pipe; and

(c) extruding the composition of the pipe to get the pipe.

Other aspects can be combined with various implementations disclosed herein to describe the invention).

DETAILED DESCRIPTION of IZOBRETENIYA

This document describes predpochtitel the hydrated embodiment, related to the composition of a pipe having improved properties during extrusion to get the pipe. What is meant by the term "pipe", is a channel for substances such as the following, but not limited to: liquids, gases, or bulk solids, such as particles, if such a channel is any size and shape suitable for such purpose and, in addition, such a channel may consist essentially of the composition of the pipe of the invention, or simply to contain such a composition pipe as one or more layers or parts.

In one implementation, the composition of the pipe contains from 80 to 99 wt.% high-density polyethylene based on the weight of the composition and from 1 to 20 wt.% filler based on the weight of the composition; however, the polyethylene has a density of from 0,940 to 0,980 g/cm3and I21from 2 to 18 DG/min (I21, ASTM-D-1238-F, 190°C/21,6 kg). The composition of the pipe is characterized by its ability to achieve high performance at low temperatures of the melt during extrusion of the composition to get the pipe. Thus, the pipe is characterized in that the composition of the pipe extruded at melt temperature Tmwhich satisfies the following relation (1):

Tm≤230-3,3(I21), (1)

where the composition is e extruded at specific performance, exceeding 1,38 kg/h/rpm to get the pipe under the following extrusion conditions: the use of the screw 60 mm, characterized by the ratio L/D 30:1 extruder with a rifled power zone, where the temperature of the melt is a melt temperature of the composition of the tubes at the edge, located downstream of the mixing zone of the extruder used in the extrusion of the composition of the pipe, while the temperature is measured using either a submersible probe ("probe"), or infrared probe ("IR"). The above equation is performed using a submersible probe, or in the case of using an infrared probe to apply equation Tm≤228-3,3(I21). Other conditions are set to satisfy equation (1)represent the following in table 1.

Table 1
The extrusion conditions for equations (1) and ratios for specific performance
Temperature zones, °C:
Rifled the food zone-
Zone 1204
Zone 2
Zone 3204
Zone 4204
Extrusion head 1204
The extrusion head 2204
Extrusion head 3204
Extrusion head 4204
Extrusion head 5204
Extrusion head 6204
Extrusion head 7204
Extrusion head 8221
Extrusion head 9221
The number of auger revolutions230-240
The speed of a stripper (ft/min)5-6
Pipe thickness average (mm)10-11

Temperature "zones" in table 1 represent the nominal temperature, i.e. they may change in the limit is +/-3°, it must understand the experts of the relevant field. The extrusion head is preferably annular, and she has such dimensions that pipe, extrudable from it, will have a specified thickness.

In a more preferred embodiment, the implementation of specific performance is in the range in excess of 1.40 kg/h/rpm, and most preferably greater than 1.42 kg/h/rpm and in another embodiment, the performance is in the range of 1.38 to 20 kg/h/rpm, and more preferably from 1,38 up to 10 kg/h/rpm and more preferably from 1.40 to 10 kg/h/rpm, and still more preferably from 1,42 up to 8 kg/h/rpm, where the desired range of performance may include any one of the lower limit described herein, or any combination of any lower limit with any upper limit described herein.

In another embodiment, the implementation of equation (1) are in the form of Tm≤235-3,3(I21), and in yet another embodiment, the implementation of equation (1) are in the form of Tm≤230-3,2(I21), and in yet another embodiment, the implementation of equation (1) are in the form of Tm≤230-3,4(I21), and in yet another embodiment, the implementation of equation (1) are in the form of Tm≤235-3,2(I21), and in one another embodiment, the implementation of equation (1) are in the form of Tm≤230-3,4(I21 ).

The conditions described in table 1, reflect the characteristic sign of the compositions of the pipe, described in this document, and are not intended to limit the invention to the stage of the method as such, because of the composition of the tubes described herein are applicable to any type of tube on any number of conditions ekstrudirovaniya and use any of the extruder, suitable for receiving the tubes, as is well known, state of the art. You can use the extruder any size, suitable for extruding the composition of the pipe when obtaining pipes, in one embodiment, the implementations use an extruder with a smooth bore or a rifled power zone, and are suitable either two-or single-screw extruders, in one implementation, the ratio of length: diameter (L/D) is in the range from 1:20 to 1:100, 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, for example, from 30 mm up to 500 mm, preferably 50 mm to 100 mm Extruders suitable for extruding compositions pipe, described herein, are further outlined, for example, Screw Extrusion, Science and Technology (James L. White and Helmut Potente, eds., Hanser, 2003).

In one embodiment, the implementation of the composition pipe extrude is a comfort to get the pipe through the annular extrusion head for extruding pipes, having a diameter of 5 to 500 mm, and from 6 to 400 mm in another embodiment, implementation, and from 8 to 200 mm in yet another variant implementation, and from 9 to 100 mm in yet another embodiment, one implementation. In another embodiment, the implementation of the composition ekstragiruyut so that the tube had a wall thickness in the range from 3 to 30 mm, more preferably from 4 to 20 mm and more preferably from 5 to 18 mm, and most preferably in the range from 7 to 15 mm

"Filler" can be any suitable filler, known to experts in the relevant prior art, containing the following, but not limited to, titanium dioxide, silicon carbide, silicon dioxide and other oxides in the number of brands of silicon dioxide, precipitated or not), antimony oxide, lead carbonate, zinc oxide, sulphur white, zirconium silicate, corundum, spinel, Apatite, barites powder, barium sulfate, magnesium oxide, carbon black, acetylene black, dolomite, calcium carbonate, talc and hydrotalcite compounds of the ions Mg, Ca, or Zn with Al, Cr or Fe and CO3and/or HPO4, hydrated or not, powdered quartz, hydrochloride, magnesium carbonate, fiberglass, clay, aluminium oxide and other oxides and metal carbonates, metal hydroxides, chromium, phosphate and brominated flame retardants, antimony trioxide, siloxane, and mixtures thereof. Fillers, about what to eat, and grades of carbon black, in particular, are described in the work of Rubber Technology, 59-104 (Chapman & Hall 1995). The composition of the pipe contains from 1 to 10 wt.% filler based on the weight of the composition of the pipe in a more preferred embodiment, implementation, and from 1.5 to 8 wt.% filler in a more preferred embodiment, implementation, and from 1.5 to 6 wt.% filler in the most preferred implementation, where desirable range may include any combination of any upper limit with any lower limit described herein. In a preferred implementation, the filler is one or more types of carbon black.

Another aspect of the invention relates to a method for producing a tube containing ensuring the availability of a mixture containing from 5 to 50 wt.% filler and from 95 to 50 wt.% low density polyethylene and from 0 to 3 wt.% one or more stabilizers; then mixing in the melt mixture and high density polyethylene characterized by a density of 0,940 to 0,980 g/cm3and I21from 2 to 18 DG/min, to obtain a target temperature dropping from 165 to 185°C with the formation of the composition of the pipe, while mixing in the melt is carried out so that the composition of the pipe contains from 1 to 20 wt.% filler based on the weight of the composition of the pipe, and then extruding the composition of the pipe is about receiving pipe. More preferably the mixture contains from 10 to 40 wt.% filler based on the weight of the mixture, and most preferably from 20 to 40 wt.% filler based on the weight of the mixture, where the linear low density polyethylene is metered in accordance with the amount of filler or stabilizer (if available). Low density polyethylene can be any suitable polyethylene, known state of the art and having a density in the range of 0.87 to 0.93 g/cm3in the preferred implementation. Most preferably low density polyethylene, which forms part of the mixture is a linear low density polyethylene.

"Target the dropping temperature reaches the mixing of the components in the melt to obtain a mixture, when using such methods, which are widely known state of the art. Can be used mixers periodic action or mixers worm type such as Brabender mixers or Kobe. Most preferably the target dropping temperature is a temperature in the range from 167 to 182°C. and even more preferably is a temperature in the range from 170 to 180°C.

"Stabilizers" include such substances, known state of the art, which include issleduemye, but not limited to: the class of compounds, such as organic phosphites, spatial-employed amines, and phenolic antioxidants. These stabilizers can be added to the compositions of the pipe in any manner, but preferably they are added as part of the mix. Such stabilizers may be present in the mixture, if any, in an amount of from 0.001 to 3 wt.% in one implementation, more preferably from 0.01 to 2.5 wt.%, and most preferably from 0.05 to 1.5 wt.%. Non-limiting examples of organic phosphites, which are suitable, are Tris(2,4-di-tert-butylphenyl)fosfat (IRGAFOS 168) and di(2,4-di-tert-butylphenyl)the pentaerythritol diphosphite (ULTRANOX 626). Non-limiting examples of spatial-obstructed amines include poly[2-N,N'-di(2,2,6,6-tetramethyl-4-piperidinyl)hexanediamine-4-(1-amino-1,1,3,3-TETRAMETHYLBUTYL)centresin] (CHIMASORB 944); bis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacina (TINUVIN 770). Non-limiting examples of phenolic antioxidants include pentaerythritoltetranitrate(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (IRGANOX 1010); 1,3,5-three(3,5-di-tertbutyl-4-hydroxybenzyl)isocyanurate (IRGANOX 3114); Tris(nonylphenyl)fosfat (TNPP); and octadecyl-3,5-di-(tert)-butyl-4-hydroxyhydrocinnamate (IRGANOX 1076); other additives include additives such as zinc stearate and zinc oleate.

Thus, the us is oasam document describes the pipes are suitable for such applications, as the transfer fluid, under pressure in one implementation, to transfer fluid can be buried under the ground by any suitable means. In order to achieve such a goal, pipes, described herein, may exhibit resistance to the rapid spread of the cracks (RCP), characterized by a critical pressure greater than 10 bar, when tested in accordance with method S-4 (ISO 13477) at 0°C. in Addition, the tube obtained in the present invention, have the grade of "D 80" or more preferably mark "D-100" or more that is known at the present level of technology for polyethylene pipes and is described, for example,PE100 Resins for Pipe Applications: Continuing the development into the 21stcentury4(12) Trends in polymer science 408-415 (1996).

Polyethylene, suitable for use in the compositions of the pipe, preferably is a polyethylene of high pressure" in the sense that they have a density (a method of obtaining a sample in accordance with ASTM D4703-03; test method for density gradient column in accordance with ASTM D1503-03) from 0,940 to 0,980 g/cm3, more preferably from 0, 942 to 0,975 g/cm3and even more preferably from 0,943 to 0,970 g/cm3and even more preferably from 0,944 to 0,965 g/cm3most preferably from 0,945 to 0,960 g/with the 3where desired density may include any combination of any upper limit with any lower limit described herein.

The high density polyethylene can be unimodal, multimodal and bimodal and preferably is multimodal or bimodal, and most preferably is bimodal. In a preferred embodiment, the implementation of bimodal high density polyethylene contains at least one high molecular weight (VM) component and at least one low molecular weight (NM) component. The term "bimodal" in the case of its use to describe the composition of polyethylene means "bimodal molecular weight distribution", where this term is understood as having the broadest meaning, which experts in the relevant field of technology gives this term as reflected in printed publications and issued patents. "Bimodal" polyolefin in accordance with the use of this term in this document is, for example, one type of polyethylene, which contains a polyolefin, characterized by at least one identifiable high-molecular-mass distribution, and polyolefins, characterized by at least one identifiable low molecular-mass distribution the population. Data of low and high molecular weight polymers can be identified in accordance with the methods of separation known state of the art for the isolation of the two polymers from a wide or having shoulders GPC curve for high density polyethylene of the invention, in another form of implementation of the GPC curve for polyethylene may demonstrate the presence of distinct peaks with depression. The polyethylene composition of the invention can be described using a combination of other characteristics.

The polyethylene is high density, suitable for use in the present invention are preferably copolymers, and more preferably a copolymer containing units derived from ethylene and C3-C10α-olefin, most preferably copolymers containing units derived from 1-hexene or 1-butene. Polyethylene high density preferably include from 1 to 10 wt.% links obtained from the co monomer, based on the weight of the copolymer, and more preferably include from 1.5 to 6 wt.% links obtained from the co monomer. low-molecular weight component preferably contains from 0.1 to 2 wt.% links obtained from the co monomer, based on the weight of the low molecular weight component, and even more preferably from 0.2 to 1.5 wt.%. High molecular weight component preferably contains from 0.5 to 8 m is S.% links obtained from the co monomer, based on the high molecular weight component, and even more preferably from 0.6 to 4 wt.% links obtained from the co monomer.

Preferably the number or content in the mixture of high molecular weight component is in the range exceeding 50 wt.% based on the weight of the entire composition is in the range from 55 to 75 wt.% another variant of realization.

In one embodiment, the implementation of high-density polyethylene contains at least one high molecular weight component, while the high molecular weight component is characterized by a measure of short-chained branching in the range from 1.8 to 10. "Branching index" represents the number of alkyl branches per 1000 carbon atoms in the main polymer chain, and can be determined using size-exclusion chromatograph (REG) for high density polyethylene, then collect fractions with different molecular masses and get their corresponding spectra1H NMR. On the basis of these spectra can determine the number of branches. In a more preferred embodiment, the implementation rate of short-chained structure is in the range from 2 to 5.

Preferably high-density polyethylene contains one high molecular weight component, characterized is the action scene mass-average molecular weight in the range more than 60,000 daltons, and more preferably greater than 70000 daltons, and even more preferably more about 80,000 daltons and less than 1,000,000 daltons, in the preferred embodiment, implementation, and less than 800000 Dalton in the preferred implementation. In addition, high-density polyethylene preferably contains one low molecular weight component, characterized by a mass-average molecular weight in the range of less than 60,000 daltons, and more preferably less than 50,000 daltons, and still more preferably from 5,000 to 40,000 daltons. These values can be determined using methods known at the present level of technology, such as helpanimals chromatography, where individual components can be distinguished and divided as described in more detail in this document.

In a preferred variant of realization of the high density polyethylene is characterized by a molecular weight distribution (ratio of mass-average molecular weight to srednekamennogo molecular mass Mw/Mn)in the range from 20 to 200 and more preferably from 30 to 100, and still more preferably from 35 to 80, where desirable range may include any upper limit and any lower limit described herein. Molecular mass distribution of ODA is to divide using the techniques, known state of the art, such as helpanimals chromatography (GPC). For example, molecular mass distribution (MMD) can be determined by the method of gel chromatography using columns with a gasket made of cross linked polystyrene; sequence pore size: 1 column less than 1000 Å, 3 columns mixture of 5×10(7) Å; the solvent is 1,2,4-trichlorobenzene at 145°C with detection of the refractive index. Data on GPC can be divided into high - and low-molecular components using models Wesslau"where a member of β for low molecular weight peak can be restricted to a specified value, preferably of 1.4, as described in the work of E. Broyer & R.F.Abbott,Analysis of molecular weight distribution using multicomponent modelsACS Symp.Ser.(1982), 197 (Comput.Appl.Appl.Polym.Sci.), 45-64.

In a preferred implementation, the value of I21high density polyethylene is in the range from 2 to 16 DG/min, more preferably from 3 to 14 DG/min and even more preferably from 4 to 12 DG/min, and most preferably from 5 to 10 DG/min, where desirable range may include any upper limit and any lower limit described herein. In addition, in another preferred variant of realization of the high density polyethylene is characterized by a value of I21/ I2(I2, of 2.16 kg, 190°C.)in the range from 0 to 200 and more preferably in the range from 80 to 180, and even more preferably from 100 to 180.

The high density polyethylene can be obtained by any appropriate means, such as suspension, mortar way, way high pressure or gas phase method, and in one embodiment, the implementation of get it, using a combination of any two or more (same or different) data, or other methods known state of the art, such as known for their ability to produce certain polyethylenes under the "manual" method. In a preferred embodiment, the implementation of high-density polyethylene receive in a single reactor, and most preferably in one gas-phase reactor of continuous fluidized bed. Such reactors are well known state of the art and are described in more detail in the documents US 5352749, 5462999 and WO 03/044061.

It is well known the use of catalysts for production of polyolefins, in particular polyethylenes. Polyethylene is high density, described herein, can be obtained by combining in a reactor one or more catalysts, and optionally an activator, preferably the composition of the bimetallic catalyst, using ethylene and one or more α-olefins, With3and C10α-olefins in one embodiment, the PE the implementation, preferably 1-butene or 1-hexene, and the selection of high-density polyethylene.

In one implementation, the composition of bimetallic catalyst contains at least one metallocene compound and at least one coordination compound of an element from groups 3 to 10, such as for example described in documents US 6274684 and US 6656868. More preferably suitable coordination complexes have a coordination number equal to either two or three or four, and include those where coordinated atoms include oxygen, nitrogen, phosphorus, sulfur or a combination of both and coordinating atom contains an atom selected from the group consisting of titanium, zirconium, hafnium, iron, Nickel or palladium. Most preferably metallocene and coordination compounds together with an activator is applied to the material of the carrier and injected into the reactor (the reactor) is preferably in the form of a hydrocarbon suspension, together with them, enter an optional third component of the catalyst to control the properties of the resulting high density polyethylene. Preferably high-density polyethylene obtained using the composition of the catalyst in one gas-phase reactor.

Thus, the compositions and methods of the present invention can be described using either any VA is Ianto implementation, disclosed herein, or a combination of any of the implementation options described in this document. The embodiments of the invention can be better understood by reference to the following examples, without considering them as a constraint.

EXAMPLES

The composition of the catalyst and polymerization to obtain a high density polyethylene of the invention

Examples of high-density polyethylene used in examples of the invention, was obtained by combining ethylene and co monomer is 1-hexene in one gas-phase reactor in the temperature range from 75 to 95°C With a catalyst composition containing subjected to a spray-dried composition (pentamethylcyclopentadienyl)(propylcyclopentanol)zirconiated, {[2,3,4,5,6-Me5C6H2)NCH2CH2)NH}Zr(CH2Ph)2and methylalumoxane with carrier, silicon dioxide (Ineos ES757). The molar ratio of Zr from amide-coordination compounds and Zr from metallocene is in the range from 2.7 to 3.5. Separately to the reactor was added an additional amount (pentamethylcyclopentadienyl) (propylcyclopentanol)zirconiated in order to regulate the relative amount of low-molecular component, thus the "ratio" between low-molecular and high-molecular components in the mixture. the rate between the components of the mixture was regulated so so according to the analysis by GPC method would receive approximately 55 wt.% high-molecular component in the calculation of the whole composition.

Used one gas-phase reactor with a fluidized bed had a diameter of 8 feet and a height of layer (from bottom distribution plate before the start of the extended partition) 38 feet. During each run, the reacting layer growing particles of polyethylene maintained in fluidized condition in the by-passing through the reaction zone of a continuous flow of raw materials, compensating expenditure of reagents and gas sent to recycling. As shown in the tables, each polymerization run, exposed to examples of the invention, used the target temperature reactor ("temperature"), namely the temperature of the reactor to approximately 75-95°C. during each run, the reactor temperature was kept at approximately constant level by raising or lowering the temperature of the gas sent to recycling, to account for any changes in the rate of release of heat due to polymerization. Fluidized bed reactor formed by granules of polyethylene. During each run, the flow of the gaseous feedstock in the form of ethylene and hydrogen was injected into the gas line, sent to recycling, to the layer of the rector. Introduction conducted along the lines send the Deposit on the recycling process stream after the heat exchanger and compressor. Liquid comonomer was introduced to the layer of the reactor. Individual streams of ethylene, hydrogen and co monomer was adjusted to maintain the target conditions in the reactor, as shown in each example. Gas concentration was measured using chromatograph operating in real time.

Properties of the resulting polyethylene high density are described in tables 2 and 3.

Conditions contact technical carbon

Experiment 1.These samples were mixed and granulated with the aid mixer periodic action Banbury F270 this rustic equipped with 15-inch single-screw extruder and pelletizing under a layer of water. The rotors of the mixer (type ST) worked at 83,5 rpm mixing Time samples of the invention and comparative samples a fallopian mixture containing carbon black, asked, trying to achieve the target temperature dropping to 170°C. the Resin stabilized with the help of Irganox 1010 and Irgafos 168. Carbon black was added, using uterine mixture. Uterine mixture containing 40% carbon black and LLDPE, was added in the amount of 5.6 wt.%, that result gave to 2.25 wt.% carbon black in the formulation.

Experiment 2.These samples were mixed and granulated with the aid of the apparatus with two protivovirusnaya augers Kobe LCM-100, carried what about the pump for melting and granulation under a layer of water. Performance on line mixing is 550 lb/h Resin stabilized with the help of Irganox 1010 and Irgafos 168. Carbon black was added, using uterine mixture according to the method similar to the method of experiment 1. Composition masterbatches was a carbon black 35 wt.%, Irganox 1010 0.2 wt.% and LLDPE 64,8 wt.%, each mass percentage is determined based on the weight of the entire composition masterbatches. Uterine mixture containing 35% carbon black was added in the amount of 6.5%, which is the result given to 2.25% carbon black in the formulation.

The conditions of extrusion tubes

Experiment 1.Experiment pipe extrusion was performed using the extruder with a rifled cylinder Cincinnati Milacron, model CMS-90-28-GP. Auger was a 90 mm screw barrier type. Extrusion head was the head of the pancake type Batterfeld. Pipe manufactured in accordance with specifications for ISO SDR 11 315 mm Other details are presented in table 3.

Experiment 2.Experiment pipe extrusion was performed using the extruder with a rifled cylinder American Maplan, model SS-60-30. Auger was a 60 millimeter barrier screw type, with the ratio L/D of 30:1. Extrusion head was the head of the pancake type. Pipe manufactured ACC is accordance with specifications ASTM SDR 11 4". Other details are presented in table 2.

Description of the test resins

Experiment 1.The formulation of the invention is characterized natural density 0,948 g/cm3(density after adding carbon black 0,958 g/cm3) and melt index under high load I216,3. Comparative examples was a commercially available bimodal resins to manufacture pipes, characterized by the density 0,945 to 0,950 g/cm3and I21from about 6 to 19 g/Dmin. You need to compare columns 2 and 4, corresponding nominally the same conditions of a rotation frequency for commercial comparative example and the example of the invention. Specific production for example of the invention in column 4 8.3% higher than the specific formulation for comparative example. The melt temperature for the sample from the sample experiment is lower.

Experiment 2.The formulation of the invention after addition of the carbon black is characterized by natural density 0,948 g/cm3(density after adding carbon black 0,958 g/cm3) and melt index under high load I216,3. DGDB-2480 is a unimodal resin related to the type ASTM 3408 or PE-80, characterized by the density 0,944 and I218. DGDA-2490 is the Oh bimodal resin, characterized by the density 0,949 and I219. Data in columns 1-3 are for run of each sample at the same nominal frequency of rotation of the auger. It is shown that the sample of the invention detects the increase in the specific production (lb/HR/rpm) 4.2% and 6.2% in comparison with DGDB-2480 and DGDA-2490, respectively. Temperature melts for all three resins under these working conditions are comparable.

Table 2
Samples of the first experiment
No. sample1234
ResinA comparative sample, a bimodalA comparative sample, a bimodalA sample of the image-acquisitionA sample of the image-acquisition
Density
(natural) (g/cm3)
0,9480,948
I21 6,36,3
Temperature zones (°C)
The zone diet2042424343
Zone 1185209213190203
Zone 2185199199187199
Zone 3185189189189189
Zone 4185208211193212
Adapter185 188192185192
Extrusion head 1185187185187184
The extrusion head 2185187188188188
Extrusion head 3185197200190191
Extrusion head 4185185185184185
Extrusion head 5-----
Extrusion head 6-191192184187
Extrusion head 7 -30394645
Extrusion head 8-192196195195
Melt (probe) (°C)226211188193
The number of auger revolutions121,2120,495,8120,2
Current motor (A)253292284289
The speed of the puller (m/min)0,3620,3800,3430,425
Torque (%)77,477,477,377,4
proizvoditel-ness, (kg/h)566,0594,6518,9642,9
Specific production (kg/h/rpm)4,674,945,425,35
The range of pipe mass (kg/m)26,05025,94025,13225,387

Experiment 2 was carried out at the characteristic conditions of the invention, such as those contained in the claims. Extruding in experiment 1 show the usefulness of the invention and its applicability to other extrusion conditions: specific performance and the temperature of the melt at the same nominal speed of the augers were superior to example of the invention in experiment 1 compared with the composition of the pipe containing commercial bimodal polyethylene.

1. A method of obtaining a pipe, including:
(a) obtaining a mixture containing from 5 to 50 wt.% filler and from 95 to 50 wt.% low density polyethylene and from 0 to 3 wt.% one or more stabilizers;
(b) smashin the e in the melt mixture and high density polyethylene, having a density of from 0,940 to 0,980 g/cm3and a melt index I21measured by method ASTM-D-1238-F under load 190°C/21,6 kg, from 2 to 18 DG/min to the target temperature dropping from 165 to 185°C., to obtain a composition containing from 1 to 20 wt.% a mixture of 80 to 99 wt.% high-density polyethylene based on the weight of the composition, while the high-density polyethylene contains at least one low molecular weight component constituting the copolymer of ethylene and C3-C10α-olefin;
(c) extruding the composition in melt temperature Tmthat corresponds to the following value:
Tm<230-3,3(I21),
and specific performance, in excess of 1.38 kg/h/rpm, followed by obtaining the pipes.

2. The method according to claim 1, characterized in that the mixture contains from 10 to 40 wt.% filler based on the weight of the mixture.

3. The method according to one of claims 1 or 2, characterized in that the high-density polyethylene contains at least one high molecular weight component and high molecular weight component is characterized by short-chained index of branching in the range from 1.8 to 10.

4. The method according to one of claims 1 or 2, characterized in that the high-density polyethylene contains at least one high molecular weight component, characterized srednevekovoi molecular m is soy, in the range exceeding 60000 D.

5. The method according to claim 1, characterized in that the composition for obtaining pipes ekstragiruyut through an extrusion head having a diameter from 10 to 500 mm

6. The method according to claim 1, characterized in that the specific performance is in the range of 1.38 to 5 kg/h/rpm

7. Composition for tubes containing from 80 to 99 wt.% high-density polyethylene and 1 to 20 wt.% filler based on the weight of the composition, and the high density polyethylene has a density of from 0,940 to 0,980 g/cm3the melt index I21measured by method ASTM-D-1238-F under load 190°C/21,6 kg, from 2 to 18 DG/min and contains at least one low molecular weight component constituting the copolymer of ethylene and C3-C10α-olefin, and the filler included in the composition in the form of a mixture which contains from 5 to 50 wt.% filler, from 95 to 50 wt.% low density polyethylene and from 0 to 3 wt.% one or more stabilizers.

8. The composition according to claim 7, wherein the high density polyethylene contains at least one high molecular weight component and high molecular weight component is characterized by short-chained index of branching in the range from 1.8 to 10.

9. The composition according to claim 7, wherein the high density polyethylene contains polymer sciense ser the regular component, characterized srednevekovoi molecular weight in the range exceeding 60000 D.

10. The composition according to claim 7, characterized in that the density of the high density polyethylene is in the range from 0,943 to 0,970 g/cm3.

11. The composition according to claim 7, characterized in that the melt index I21high density polyethylene is in the range from 4 to 16 DG/min

12. The composition according to claim 7, wherein the high density polyethylene is characterized by a molecular weight distribution in the range from 20 to 200.

13. The composition according to claim 7, characterized in that the filler is a carbon black.

14. Composition according to one of claims 7 to 13, characterized in that the high-density polyethylene receive in a single reactor.

15. The composition according to 14, characterized in that the reactor is a gas-phase reactor.

16. Composition according to one of claims 7 to 13, characterized in that the high-density polyethylene obtained in one or more reactors containing composition of bimetallic catalyst with ethylene and one or more α-olefins.

17. The composition according to item 16, characterized in that the composition of bimetallic catalyst contains at least one metallocene compound and at least one coordination compound of an element from groups 3 to 10.

18. TRU is a, characterized in that it is obtained by the method according to one of claims 1 to 6 of the composition according to one of claims 7 to 17, and has a resistance to rapid crack propagation (RCP)at the critical pressure above 10 bar, when tested in accordance with method S-4 (ISO 13477) at 0°C.

19. Pipe, characterized in that it is obtained by the method according to one of claims 1 to 6 of the composition according to one of claims 7 to 17, and has a wall thickness in the range from 5 to 30 mm



 

Same patents:

FIELD: technological processes.

SUBSTANCE: inventions relate to pipe of flaky composite material and method of its manufacturing. Method for manufacturing of pipe includes winding of inner glass plastic layer onto mandrel, bonding of intermediate foam plastic layer and winding of ribs and outer layer of glass plastic. In intermediate foam plastic layer there are circular grooves arranged for location of ribs. Ribs and outer layer is wound in a single technological operation by bundle of cross threads. Bundles are equipped with longitudinal threads, using method of cross-fibred longitudinal-transverse winding. At the same time longitudinal threads are bent as bundle changes from winding of external layer to winding of ribs and back with filling of each groove by mentioned bundle till ribs are formed.

EFFECT: improved manufacturability and reliability of glass plastic pipes operation.

2 cl, 4 dwg

Pressed shell // 2387910

FIELD: machine building.

SUBSTANCE: invention refers to pipe fabrication. The pressed shell containing layers of roll woven cloth with binding is made with circular layers of woven material in form of separate strips of length not less, than length of shell and width equal to perimetre of the latter with overlap.

EFFECT: increased reliability and expanded process functionality of pressed shell.

2 cl, 2 dwg

FIELD: transport.

SUBSTANCE: meshed cover in the form of rotation body from composite materials includes spiral and circular ribs comprised of layers repeated throughout the cover wall thickness of the systems of crossing spiral and circular strips. Inclined strip passages between circular strips are equally offset relative to each other in circumferential and spiral directions and are made in the form of one family of congruent continuous circular zigzag-shaped spirals located along circular surfaces, which is common to circular surfaces of layers of the systems of crossing spiral and circular strips. Tops of zigzags are adjacent to circular strips of circular ribs crossing in the gap between them with spiral strips or spiral and circular strips of spiral and circular ribs correspondingly so that circular zigzag-shaped ribs are formed and mainly arranged on cover ends.

EFFECT: increasing rigidity, improving reliability and decreasing the weight of the design.

4 cl, 4 dwg

FIELD: construction.

SUBSTANCE: invention is related to method for manufacturing of pipeline. Method provides for filling of space between ends of pipe composite layers by winding of fibrous material impregnated with binder, and attachment of composite layers is provided via winding of additional layers of fibrous material impregnated with binder on them and onto fibrous material with further polymerisation.

EFFECT: expansion of assembly resources and improved reliability after welding of pipe polymer layers.

1 dwg

FIELD: construction.

SUBSTANCE: invention is related to the field of pipes from plastic masses. In method of combined pipe manufacturing, including arrangement of sealing thermoplastic layer on technological mandrel, winding of fibrous material with binder and polymerisation, sealing layer is arranged by winding of extruded thermoplastic tape onto mandrel with overlap and simultaneous heating of joint of the latter in process of winding, then layer of woven cellular fibrous material is wound with partial penetration into uncooled sealing layer, and fibrous material with binder is laid over this layer with further polymerisation.

EFFECT: improved reliability.

3 dwg

FIELD: construction.

SUBSTANCE: invention is related to the field of pipes production from composite materials. In method for production of pipe, including installation of polymer pipe on mandrel, arrangement of primer layer on it, winding of fibrous material with binder and polymerisation, after installation of polymer pipe onto mandrel its surface layer is heated till yield state, and primer layer is arranged on it by means of woven cellular material winding on it, and then fibrous material is wound with binder and polymerised.

EFFECT: improved reliability.

1 dwg

FIELD: aircraft engineering.

SUBSTANCE: proposed air duct can feed air in the temperature range of minus 55°C to plus 85°C and at load with pressure difference relative to aircraft cabin inside pressure not exceeding ±500 GPa. Air duct outer or inner side is furnished with multi-layer reinforcing coat. Every layer has a number of coils formed by at least one continuous fiber. Coils of layers arranged one above another are wound in opposite directions to form the coat cellular structure. Air duct is made from foamed or dense plastic material. Aforesaid continuous fibers are enclosed by matrix made from either thermosetting plastic or thermoplastic polymer. Distance between said coils or angle of inclination between them and air duct lengthwise axis varies along said axis to change coils density along air duct lengthwise axis depending upon local requirements to air duct mechanical strain.

EFFECT: air duct reduced weight and increased strength.

12 cl, 8 dwg

FIELD: construction industry.

SUBSTANCE: method involves overlapped winding of annular woven fabric layers on elastic mandrel in the form of straps with length not less than length of cover and width equal to perimetre of the latter; each annular layer is fixed with spiral winding of textile fibre, and after all layers are wound and fixed, woven fabric is stitched with zigzag seam of thread made from fibrous material, woven fabric is soaked with bonding agent, drying, installation in split die, heating of assembly and polymerisation, and after it is completed, assembly is cooled, cover with mandrel is removed from die and taken from mandrel.

EFFECT: enlarging manufacturing capabilities and improving reliability.

4 dwg

FIELD: machine building.

SUBSTANCE: invention can be used for creation of pipeline in different fields of engineering, for instance in construction, communal services and in metal mining industry at transportation of polluted waste water, loose products, pulps, mountain mass and other liquids, containing solid phase. Pipe is implemented of multilayer composite - fibrous material. It is formed in the form of alternating mono-layers with transversal and longitudinal folding of reinforcing material, impregnated by binding. In structure of pipe material it is provided protective inner layer, which allows reduced content of binding and particularly is impregnated by longitudinal fibers as compared with other layers of pipe. Mono-layers of protective layer are oriented in longitudinal section of pipe by direction to its axis under acute angle to direction of flow of relocatable bodies.

EFFECT: there is increased durability of pipe ensured by increasing of hydroabrasive durability.

6 cl, 3 dwg

FIELD: machine building.

SUBSTANCE: polymeric pipe, wall of which allows external layer, internal layer at least one intermediate layer, herewith nearby layers are connected to each other, and, at least, one layer, excluding inner layer, is implemented in the capacity of functional layer, which a) contains thermoreactive polymer, which in comparison with thermoreactive polymer, at least of one, following by radius inside layer differs, at least, by one physical character: coefficient of elasticity is less, percentage elongation against rupture is more, softening temperature is less, and/or b) contains at least one additive, which in case of application of impact energy on external layer is irreversibly deformed.

EFFECT: shock strength increasing of pipes.

22 cl, 4 dwg

FIELD: chemistry.

SUBSTANCE: present invention relates to a polyethylene composition with multimodal molecular weight distribution for blow moulding canisters with volume ranging from 2 to 20 dm3 and a method of preparing the said composition. The composition has density ranging from 0.950 to 0.958 g/cm3 at 23°C and melt flow rate (MFR190/5) from 0.30 to 0.50 dg/min. The composition also contains 40 to 50 wt % low molecular weight ethylene homopolymer A and 25 to less than 30 wt % high molecular weight copolymer B obtained from ethylene and another 1-olefin containing 4 to 8 carbon atoms, and 24 to 28 wt % ethylene copolymer C having ultra-high molecular weight.

EFFECT: obtained composition has good resistance to chemical effect, especially high mechanical strength, high corrosion resistance and is a naturally light material; high melt strength of the composition enables prolonged extrusion without breaking the workpiece, and an accurately selected swelling index of the composition enables optimisation of controlling thickness of the wall of the article.

10 cl, 1 tbl, 1 ex

FIELD: chemistry.

SUBSTANCE: polyethylene in form of ethylene homopolymers and copolymers of ethylene with α-olefins and having molecular weight distribution range Mw/Mn from 6 to 100, density from 0.89 to 0.97 g/cm3, weight-average molecular weight Mw from 5000 g/mol to 700000 g/mol and from 0.01 to 20 branches/1000 carbon atoms and at least 0.5 vinyl groups/1000 carbon atoms, where the fraction of polyethylene with molecular weight less than 10000 g/mol has degree of branching from 0 to 1.5 branches on the side chains, longer than CH3/1000 carbon atoms. The catalyst composition for synthesis of polyethylene in paragraph 1 consists of at least two different polymerisation catalysts, from which A) is at least one polymerisation catalyst based on monocyclopentadienyl complex of a group IV-VI metal, in which the cyclopentadienyl system is substituted by an uncharged donor (A1) of formula Cp-Zk-A-MA (II), where variables assume the following values: Cp-Zk-A is , MA is a metal which is selected from a group consisting of titanium (III), vanadium, chromium, molybdenum and tungsten, and k equals 0 or 1, or with hafnocene (A2), and B) is at least one polymerisation catalyst based on a ferrous component with a tridentate ligand containing at least two ortho-, ortho-disubstituted aryl radicals (B).

EFFECT: obtaining polyethylene with good mechanical properties, possibility for processing and high content of vinyl groups.

27 cl, 12 ex, 2 tbl, 5 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to high-strength bimodal polyethylene compositions which are meant for preparing compositions for pipes, particularly high-strength compositions for pipes. The composition has density equal to or greater than 0.940 g/cm3, overall polydispersity index equal to or greater than 25 and contains a high-molecular polyethylene component and a low-molecular polyethylene component. The ratio of weight-average molecular weight of the high-molecular component to the weight-average molecular weight of the low-molecular component of the composition is equal to or greater than 30. The weight-average molecular weight of the low-molecular polyethylene component ranges from 5000 to 30000. The composition is classified as PE 100 material, has proper balance of properties such as strength and hardness, as well as good processing properties. A pipe made from the composition which has undergone internal strength tests has extrapolated stress equal to or greater than 10 MPa when the internal strength curve of the pipe is extrapolated to 50 or 100 years in accordance with ISO 9080:2003(E).

EFFECT: increased strength of products.

15 cl, 6 tbl, 10 ex

FIELD: chemistry.

SUBSTANCE: present invention relates to a method of preparing an ethylene polymer composition. Described is a method of preparing an ethylene polymer composition in a multistage process. The said method involves polymerisation of only one of ethylene or ethylene with a comonomer to obtain ethylene polymer at the first stage, supply of the polymer obtained at the first stage to the second stage, where at the second stage only one of ethylene or ethylene with a comonomer is polymerised in the presence of the polymer obtained at the first stage, and where the first stage is a suspension polymerisation stage, and polymerisation at the first stage is carried out in the presence of a catalyst system containing: (a) a precursor solid catalyst containing a transition metal selected from titanium and vanadium; magnesium, haloid, electron donor and solid dispersion material containing inorganic oxide, and (b) organoaluminium compound; and where the average diametre of particles of the precursor solid catalyst obtained per total volume of the precursor solid catalyst, D50, ranges from 1 to 13 micrometres. Also described is an ethylene polymer composition obtained using the said method, having density in the range 0.915-0.970 g/cm3 and MI5 in the range 0.02-3.5 dg/min and less than 6 regions of gel per m2 with size greater than 800 micrometres, and less than 100 regions of gel per m2 with size ranging from 400 to 800 micrometres, where the amount and size of gel is determined for a 5 m2 cast film sample with thickness of 50 micrometres, obtained from the ethylene polymer composition; also described is an industrial product made from the said composition. Described is an ethylene polymer composition obtained using the said method, having density in the range 0.915-0.970 g/cm3 and MI5 in the range 0.02-3.5 dg/min, where the composition has Young's modulus during bending, measured using an Instron device in accordance with ISO 178, exceeding 1340*{1-exp[-235*(density-0.9451)]}; ethylene polymer composition having density in the range 0.915-0.970 g/cm3 and MI5 in the range 0.02-3.5 dg/min, where the composition has Young's modulus during bending which exceeds 1355*{1-exp[-235*(density-0.9448)]}. Described is a composition obtained using the said method and containing bimodal polyethylene resin, and where the bimodal polyethylene resin contains high-molecular ethylene polymer and low-molecular ethylene polymer, and where the low-molecular ethylene polymer has MI2 ranging from 10 g/10 min to 1000 g/10 min and density of at least 0.920 g/cm3, and where the composition has density ranging from 0.915 g/cm3 to 0.970 g/cm3.

EFFECT: improved mechanical properties of products made from the compositions, reduced amount of gel in the compositions.

20 cl, 38 ex, 1 dwg, 4 tbl

FIELD: chemistry.

SUBSTANCE: thermoplastic elastomer material contains: (a) from 10 to 100 wt % of at least one thermoplastic elastomer based on styrene; (b) from 0 to 90 wt % of at least one thermoplastic homopolymer or copolymer of α-olefin, different from (a); where amount of (a)+(b) equals 100; (c) from 2 to 90 pts. wt of vulcanised rubber in crushed state; (d) from 0.01 to 10 pts. wt of at least one coupling agent which contains at least one unsaturated ethylene; where amounts (c) and (d) are expressed in ratio to 100 pts. wt of (a)+(b).

EFFECT: improved mechanical properties, specifically breaking stress and breaking elongation, increased wear resistance.

60 cl, 6 tbl, 6 ex

FIELD: process engineering.

SUBSTANCE: invention relates to techniques of producing high-strength thermosetting films. Proposed method comprises mechanical missing of granules of several types of polyethylene and film extrusion with its subsequent pneumatic expansion. Extrusion rate makes over 18 m/min. Mix of granules contains unimodal low-pressure polyethylene and bimodal high-pressure polyethylene.

EFFECT: optimum ratio of components allow optimum physicochemical parametres and increased strength.

2 dwg, 2 tbl

FIELD: chemistry.

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

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

9 cl, 1 ex, 1 tbl

FIELD: chemistry.

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

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

9 cl, 1 tbl, 1 ex

FIELD: chemistry.

SUBSTANCE: present invention relates to the technology of obtaining rubber, particularly to hydrogenated or non-hydrogenated nitrile rubber, to the method of obtaining it, to a polymer composite material, to the method of obtaining it and method of making moulded objects. Hydrogenated or non-hydrogenated rubber is obtained, with molecular weight Mw between 20000 and 250000, Mooney viscosity -ML 1+4 at 100°C between 1 and 50 and polydispersity index of not more than 2.5. The polymer composite material contains not less than one hydrogenated or non-hydrogenated nitrile rubber, not less than one filler and not less than one crosslinking agent. Without adding coolefin, the nitrile rubber is subjected to metathesis in the presence of Grubbs's catalyst in an inert solvent.

EFFECT: obtaining hydrogenated or non-hydrogenated nitrile rubber with low molecular weight and narrower molecular weight distribution.

13 cl, 4 tbl, 4 ex

FIELD: chemistry.

SUBSTANCE: invention relates to obtaining compositions for production of pressure pipes. Composition is obtained from mixture of (a) polyethylene resin, containing fractions which have large molecular weight and fractions which have low molecular weight, and (b) ionomer. As ionomer, copolymer, which represents copolymer of alpha-olefin and ethylene-unsaturated carboxylic acid and/or anhydride, partly neutralised by metal ions or amines.

EFFECT: obtaining resins which have high resistance to creep at low temperature preserving high resistance to slow growth of cracks and shock resistance.

8 cl, 6 tbl, 3 dwg

FIELD: chemistry.

SUBSTANCE: methods are described for preparing polymer nanocomposites using organic solvents or mixtures of solvents. At least one isobutylene-based elastomer is brought into contact with at least one sheet filler, at least one solvent and vulcanising substance. The obtained composition has oxygen penetration rate at 40°C of approximately 150 mm·cm3/[m2·day] or less. In the second version at least one isobutylene-based elastomer is brought into contact with a solution containing at least one sheet filler to obtain a composition. In the third version a solution (a) is brought into contact with a solution (b), and at least one solvent and at least one hydrocarbon are removed from the product. Solution (a) contains at least one hydrocarbon and at least one sheet filler, and solution (b) contains at least one solvent and at least one isobutylene-based elastomer. The nanocomposition obtained using any of the versions is free from functionalising amines.

EFFECT: provision for optimum elasticity of polymer nanocomposites, as well as higher efficiency and/or simplicity of the design when the reactor system is combined with subsequent treatment processes.

27 cl, 2 tbl, 6 dwg, 25 ex

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