Polymer moulding compositions

FIELD: chemistry.

SUBSTANCE: invention relates to polymer moulding compositions meant for moulding screw fitments. The composition contains a copolymer of ethylene and 1-hexene with density between 0.947 and 0.962 g/cm3 and melt index between 2 and 8 g/10 min and another copolymer of ethylene and 1-hexene with density between 0.912 and 0.932 g/cm3 and melt index between 0.25 and 6 g/10 min. Difference in density of the two polyethylenes is equal to or greater than 0.03 g/cm3. Selection of the components enables to obtain polymer compositions which have sufficient resistance to cracking and impact strength at low production expenses and without loss of other necessary operational properties.

EFFECT: screw fittings made from the said composition have strength which conforms to requirements for maintaining pressure, particularly in bottles with carbonated drinks, as well as plasticity for providing an airtight seal without need for lining and without change in taste or smell of the contents of the bottle.

9 cl, 4 ex, 6 tbl

 

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the priority of provisional patent application U.S. No. 60/568487, filed may 6, 2004, pursuant to Section 35, United States Code § 119(e). Such application is fully incorporated into this description by reference.

The technical FIELD TO WHICH the INVENTION RELATES.

The present invention relates to polymeric compositions having the desired properties. In particular, the present invention relates to sealing means made of compositions based on polyethylene polymer.

The LEVEL of TECHNOLOGY

The present invention relates to polymeric molding compositions intended for molding and, in particular, for forming screw closures. For the manufacture of screw closures such as caps for bottles and soda (carbonated) water, usually use polypropylene (PP), providing the required strength of the capping means, while the inner lining is made from plastic copolymer of ethylene and vinyl acetate (EVA), PVC, SEBS (a styrene-ethylbutane-styrene), TPV (thermoplastic vulcanizer), butyl rubber, etc. that allow you to create an airtight seal. However, such a double-element construction is expensive, so users are on the constant search for ways to solve this problem at a lower cost. It would be much easier and more convenient to use a singleton sealing means without gaskets. However, to create such a design is difficult, because capping the cover should be strong enough to meet the specified requirements and is flexible enough to provide a tight seal without changing the taste or smell of the bottle contents. In particular, the sealing cap must withstand the pressure of the bottle contents, to have good crack resistance and impact strength, along with good characteristics torque loosening and torque breakdown thread, with excellent color characteristics.

When bottles for soda water in polyethylene terephthalate (PET) were created polymers for the manufacture of polypropylene (PP) caps, satisfying the need in a convenient, protected against inadvertent unscrewing and cheap closures for these bottles. Such closures have the form of a cap which is put on the bottle and has a basis of open ear or locking ring that protects against inadvertent loosening. Despite the cheapness of modern polypropylene closures, they are too hard for the formation of a gas-tight seal with the bottle. On the to perform the second operation, as a result of which the inner side of the polypropylene cover attach pad of a copolymer of ethylene and vinyl acetate (EVA) or other material that serves as a sealing layer. This creates a flexible polymeric seal, providing a gas-tight sealing means. Such a closure means or cap has good functional properties, but the making of such a two-element design is expensive. Therefore, a need for new polymers, which can solve the existing technical problems associated with the manufacture of closures, and thus to make them cheaper. The above applies to tanks with high blood pressure, and to tanks with normal pressure.

To solve the manufacture of closures have been proposed various polymer molding composition comprising a mixture of linear low density polyethylene (LLDPE) high density polyethylene (HDPE). For example, in U.S. patent No. 5981664, which is included in the present description by reference, describes a polymer molding compositions containing 40-65% polyethylene with a density of from 0,948 g/cm3to 0,964 g/cm3, a melt flow index from 6 to 20 g/10 minutes and an average molecular weight distribution Mw/Mn of from 2 to 5 and 35-60% of the floor is of ethylene with a density of from 0.935 g/cm 3to 0,953 g/cm3, a melt flow index from 0.1 to 0.35 g/10 minutes and an average molecular weight distribution Mw/Mn of from 6 to 20, with the final composition has a density from 0,948 g/cm3to 0,957 g/cm3the melt flow index of 1.0 to 2.0 g/10 minutes, the average molecular weight distribution Mw/Mn of from 3 to 10, and the difference in densities of the two components from 0 to 0,029 g/cm3. It is believed that such compositions suitable for the manufacture of screw closures.

However, there is still a need in the polymer compositions suitable for molding closures with acceptable properties, in particular, without gasket, with the desired taste and smell, satisfactory crack resistance and impact strength.

The INVENTION

One object of the present invention is a composition based on polyethylene, which in some embodiments of the invention can be used without gaskets to replace the two-element structure of polypropylene/copolymer of ethylene and vinyl acetate (EVA), previously used for the manufacture of caps for bottles. In certain embodiments the invention, this composition is characterized by resistance to cracking in environmental conditions (ESCR) >80 hours at 100% igepal (Igepal) (the test is performed the method American society for testing materials (ASTM) D-1693, condition C), elongation at break 210-238 ATM (3000-3400 psi) according to ASTM D-638 in the acquisition and test method ASTM D 4976, but remains sufficiently flexible for tight sealing of the bottle, preventing leakage of gases, and satisfies the requirements of torque automatic screwing of the cap and torque to disrupt the thread.

One object of the present invention is a composition comprising a single component polymer with a density 0,935-0,955 g/cm3and a melt index of 0.3-1.2 g/10 minutes, which is a polyethylene.

One object of the present invention is a composition comprising from about 10 to about 90 wt.% polyethylene with a density of from about 0,947 to 0,962 g/cm3and a melt index from about 1 to about 10 g/10 minutes and from about 90 to about 10 wt.% polyethylene with a density of from about 0,912 to 0,932 g/cm3and a melt index from about 0.25 to about 6 g/10 minutes, the dierence of the densities of the components (a) and (b) (∆D = D(A)-D(In)) is equal to or greater than 0.03 g/cm3.

One object of the present invention is a sealing means consisting of at least one of polyethylene, characterized by the distribution of short-chained branching equal to or greater than about 8% to about 25%.

One object of the present invention is the I method of making closures, which includes the modification of the composition according to claim 1 or 7 with the formation of closures.

Other objects and advantages of the present invention will be clear from the following description of the invention and the accompanying claims.

DETAILED description of the INVENTION

As indicated above, the present invention relate to compositions based on polyethylene having the desired properties. In certain applications of the composition according to the present invention are characterized by resistance to cracking in environmental conditions (ESCR) >80 hours at 100% igepal (test performed by the method of ASTM D-1693, condition B), elongation at break 3000-3400 psi in accordance with ASTM D-638 in the acquisition and test method ASTM D 4976, but remain plastic enough for the hermetic sealing of the bottle, preventing leakage of gases, and satisfy the requirements of torque automatic screwing of the cap and torque to disrupt the thread.

Used here is the term "torque breakdown thread" means the amount of torque which can be applied by machine for capping bottles without breaking the thread. In addition, the importance of ease of unscrewing the lid to the consumer. This indicator is generally defined as torque, tvinci the project for a cover. To prevent ejection of the cap from the bottle, you should consider the periodic temperature change while maintaining the CO2the cover design, the strength of the thread (module) and foaming (which may or may not occur). Made the cover must withstand a force of up to 55 DIN generated by the marking soluble, aqueous, UV or other paints. Carbonated drinks are usually under pressure of from about 30 to about 60 psi depending on the temperature.

Manufacturers of soda water is often injected under pressure of carbon dioxide in cold liquid and then sealed bottles under high pressure. The application of this process can be explained by the fact that in a cold fluid, under high pressure, dissolve more gas than warm fluid not under pressure. The bubbles in these drinks not only cause the hiss, but also change the taste of the drink. Carbon dioxide in soda water forms carbonic acid, which weakens the sweet taste of the drink. So degassed soda water often has a sweeter taste than carbonated water. Carbon dioxide not only changes the flavor and taste, but also has antibacterial action. It is established that carbon dioxide inhibits the growth of microbes in the mouth. With the new drinks of different types contain different amounts of carbon dioxide and thus, under different pressure. On average 350 g (12 oz) cans of soda water sold in the U.S. are under pressure of about 120 kPa (17.4 psi) during capping at 4°C and under a pressure of 250 kPa) (36.3 psi) when stored at 20°C.

One application of compositions based on ethylene of the present invention is the molding of caps for bottles, for example, for the above bottles with soda water.

The polymer should possess the following important properties inherent to the polymer or achievable by adding different adjuvants, which include the ability extrusion acceptable thrust (engine load), the creation of pressure in the head, specific performance and receiving surfaces without defects and fracture extrusion flow, spoiling the appearance of the bottle caps.

A mixture of two polymers are typically characterized by inferior properties compared to the properties of the individual components or with linear interpolation properties of the two components. However, the authors of the present invention discovered that by proper selection of the components of the mixture can be achieved best properties of ESCR in the range elongation at break, are necessary for this application, without the loss of other essential operational properties.

Cover of otoplenie by the method of direct compression using the compositions of the present invention, have an excellent balance of properties at lower cost to the manufacturer. The plasticity of the mixture provides excellent sealing cap that meets the requirements. Thus, embodiments of the present invention, which used a mixture of the following components provide the necessary efficiency and economy, in comparison with the polymers commonly used for the manufacture of caps for bottles. These compositions can also be subjected to the injection molding.

The polymer components can be mixed by any method known to specialists in this field. For example, you can mix the dry mixture of the two components in the extruder. Alternatively, the polymer composition can be obtained in multiple reactors and/or with the help of several catalysts. Mixing can easily be produced without the occurrence of problems related to incompatibility of the components.

The authors present invention has created a polymeric composition suitable for molding screw capping means possessing good taste and smell, as well as adequate resistance to cracking and impact strength. Screw closures made from the compositions of the present invention, do not require gaskets. These compositions are obtained on the basis of t is moplastic polymers, in particular polyethylenes. The first of these polymer compositions include:

(A) from about 10 to about 90 wt.% polyethylene with a density of from about 0,947 to about 0,962 g/cm3, a melt index from about 1 to about 10 g/10 minutes, preferably from about 2 to about 8 g/10 minutes, more preferably from about 3 to about 7 g/10 minutes;

(B) from about 90 to about 10 wt.% polyethylene with a density of from about 0,912 to about 0,932 g/cm3, a melt index from about 0.25 to about 6 g/10 minutes, preferably from about 0.5 to about 4 g/10 minutes, more preferably from about 0.75 to about 3 g/10 minutes; and

(C) 0-6 wt.% additives selected from the group including color enhancers, lubricants, fillers, pigments, antioxidants and substances to improve the processing properties, preferably in the range from about 0.01 to 3 wt.% and most preferably in the range of 0.015 to 0.5 wt.%;

where the difference between the densities of the components (a) and (b) (∆D = D(A)D(B)) is equal to or greater than 0.03 g/cm3.

In another embodiment of the invention these compositions include polyethylene, characterized by the distribution of short-chained branching equal to or greater than from about 8 to about 25%, preferably polyethylene contains at least about 80% fraction of high density.

In another embodiment, compositions of the invention preferably will win 1-hexene in the amount of from about 0.5 to about 5 wt.% and more preferably soluble fraction more than around 1.75% (determined by CRYSTAF method).

In addition, one-component polymer compositions are appreciated due to the simplicity of their manufacture. Another variant implementation of the invention belongs to the second type of polymer compositions, including single-component polymer that are exceptionally well suited for molding screw capping means possessing good mechanical properties tensile, good taste and smell, as well as adequate resistance to cracking, impact strength and color. Such screw closures made from the compositions of the present invention, do not require gaskets. These compositions based on thermoplastic polymers, in particular polyethylene. Examples of such compositions include:

(A) one-component polymer with a density 0,935-0,955 g/cm3preferably 0,938-0,952 g/cm3and most preferably 0,942-0,950 g/cm3, a melt index in the range of 0.3-1.2 g/10 minutes, preferably 0.4 to 1.1 g/10 minutes and most preferably 0.5 to 1.0 g/10 minutes;

(In) 0-6 wt.% additives selected from the group including color enhancers, lubricants, fillers, pigments, antioxidants and substances to improve the processing properties, preferably in the range from 0.01 to 3 wt.% and most preferably in the range of 0.015 to 0.5 wt.%.

In another embodiment, the invention is Azania kopazicii contain polyethylene, characterized by the distribution of short-chained branching equal to or greater than about from about 10 to about 24%, preferably polyethylene contains less than about 60-85% fraction of high density and about 5-16% products purging.

In another embodiment, compositions of the invention preferably contain 1-hexene in the amount of from about 0.5 to about 5 wt.% and more preferably soluble fraction more than around 1.75% (determined by CRYSTAF method).

In one embodiment of the present invention sealing means made of any polymeric composition, characterized by excellent performance torque unscrewing torque breakdown thread migration slippage and can guarantee a tight seal under pressure up to 150 psi. Torque loosening represents the magnitude of the torque force required for loosening, opening or removal of the closures to bottles. In accordance with one embodiment of the present invention, the data closures have torque loosening within about 7-17 lb-inches. As mentioned above, the torque stall carving represents the amount of torque which can be applied by machine to the bottle cap without cry the and thread.

In accordance with one embodiment of the present invention sealing means made of any polymeric composition, characterized torque breakdown thread within about 20-50 lb-inches. To ensure the migration of the slip in the polymer is injected about 500-3000 ppm additives, reducing friction. Typical additive, reducing friction, is erucamide. These closures are able to provide a hermetic seal at pressures up to 150 psi. The composition may also be introduced substances to improve technological properties, which allow to obtain the surface without destroying the extrusion flow that is needed for aesthetic purposes or to facilitate marking.

Closures, in particular screw sealing means made of the above polymer compositions of any type, is also in the scope of the present invention.

Professionals in this field must be known that polymers can be compounded (mixed) (two polymer (plus any additives) in the case of a mixture or blend plus one or more additives) using methods known in this field. Components and additives are mixed in a standard mixing equipment known to specialists in this field, which includes, but is not limited to what as them: twin screw mixers, in which the screws rotate in the same or in opposite directions, are linked or non-linked, have one, two or more steps and different configurations of screws, along with a pump to melt, feeding the polymer through the die plate for granulation under water. Alternatively, you can use a Bunbury mixer with single-screw extruder and Villeroy for granulation under water.

The polymer composition in the form of a mixture of components you can get in the series-connected two-stage reactors, the principle of which consists in the fact that the catalyst is fed into the first reactor through a feed tube, then the mixture of the polymer and the active catalyst is transferred from the first reactor to the second reactor where get another polymer and mixed in situ with the copolymer of the first reactor. When implementing this method if you want you can use more than two reactors. These reactors can be independent reactors or stages of the same reactor. The catalyst may be in the media, can be without media or be present in the solution before feeding it to the reactor. The catalyst can be fed to the reaction system continuously to ensure sustainable operation mode, but the supply may be interrupted for short periods of time to facilitate replacement of razlichnyei catalyst.

Gaseous substances used in this way, you can enter the reactor as recycle gas. The recirculated gas is a mixture of gases that includes only the ethylene or ethylene and one or more alpha-olefins, preferably one or two alpha-olefins, are used as comonomers (alpha-olefin necessarily included in the recirculating gas fed to the first reactor, and not necessarily in the composition of the recycle gas fed to the second reactor), and one or more inert gases such as nitrogen (to create the necessary pressure in the reactor), inert hydrocarbons and hydrogen. The alpha-olefins may include, for example, propylene, 1-butene, 1-hexene, 4-methyl-1-penten and 1-octene. Alpha-olefins are usually not more than 12 carbon atoms, preferably 3-8 carbon atoms. The recirculated gas can also be called "the incoming gas or circulating gas."

Below is preferred combinations of comonomers:

the first reactorthe second reactor
1-hexene1-hexene
1-butene1-hexene
1-butene1-Boo is EN
1-hexene1-butene

It should be noted that polyethylene can be obtained in the first or second reactor, preferably in the second reactor, if desired. Obviously, the mixture obtained in situ, can in General be characterized as bimodal polymer. However, in some cases, the two components forming the mixture, have almost the same molecular weight, so that there is no noticeable gap in the curve of the molecular weight.

In multi-stage reaction system, the amount of each component can be controlled taking into account the relative performance of each reactor. The relative performance of each reactor can, in turn, be controlled by application of the computer program that controls the performance of the reactors (as measured by heat balance) and changes the partial pressure of ethylene in each reactor and the feed rate of the catalyst in accordance with the requirements of performance, the ratio of components in the mixture of products and the performance of the catalyst.

One-component polymer composition can be obtained in a single reactor with a flow of catalyst feed pipe. The catalyst may be in the media, to be without media or to present the solution to the feed to the reactor. The catalyst can be fed to the reaction system continuously to ensure sustainable operation mode, but the supply may be interrupted for short periods of time to facilitate the substitution of different batches of catalyst.

Gaseous substances used in this process, you can enter the reactor as recycle gas. The recirculated gas is a mixture of gases that includes only the ethylene or ethylene and one or more alpha-olefins, preferably one or two alpha-olefins, are used as comonomers, and optionally one or more inert gases such as nitrogen (to create the necessary pressure in the reactor), inert hydrocarbons and hydrogen. The alpha-olefins may include, for example, propylene, 1-butene, 1-hexene, 4-methyl-1-penten and 1-octene. Alpha-olefins are usually not more than 12 carbon atoms, preferably 3-8 carbon atoms. The recirculated gas can also be called "the incoming gas or circulating gas."

DESCRIPTION CATALYST

As an example, the catalytic system can result in a catalytic system based on magnesium/titanium, which is described in U.S. patent No. 4302565. The referenced patent is fully incorporated into the present description by reference. Another catalytic system is a system in which the catalyst precursor is are square by spray drying and used in the form of a suspension. Such a catalyst precursor contains, for example, titanium, magnesium, electron donor and optionally a halide of aluminum. Then the specified catalyst precursor is introduced into the hydrocarbon medium, such as mineral oil, to obtain a suspension. Dried by spraying the catalyst described in U.S. patent No. 5290745, which is fully incorporated into the present description by reference. These catalytic systems can be defined as the catalytic system of the Ziegler-Natta.

Typical catalytic systems based on magnesium/titanium can be described as follows. The catalyst precursor can have the formula of MgdTi(OR)eXf(ED)gwhere R is an aliphatic or aromatic hydrocarbon radical containing 1-14 carbon atoms or COR'where R' represents an aliphatic or aromatic hydrocarbon radical containing 1-14 carbon atoms; all groups OR may be the same or different; X is independently denotes chlorine, bromine or iodine; ED denotes an electron donor; d is 0.5 to 56; e is 0, 1 or 2; f is 2-116; and g is 1,5d+2. The specified catalyst precursor can be obtained from compounds of titanium, magnesium compounds and electron donor. The titanium compounds which can be used to obtain the precursor of the catalyst, have the formula Ti(OR)eXh where R, X and e have the values indicated above; h is an integer from 1 to 4; and e+h is 3 or 4. Some typical examples of titanium compounds include TiCl3, TiCl4, Ti(OC2H5)2Br2, Ti(OC6H5)Cl3, Ti(OCOCH3)Cl3and Ti(OCOC6H5)Cl3. The preferred compounds are TiCl3and TiCl4. Compounds of magnesium include magnesium halides such as MgCl2, MgBr2and MgI2. The preferred compound is anhydrous MgCl2. On one mol of the titanium compounds used about 0.5 to 56, preferably about 1-10 moles of magnesium compounds.

The electron donor is an organic Lewis base, preferably liquid at temperatures in the range of from about 0°to about 200°C, in which dissolve compounds of magnesium and titanium. The electron donor can be difficult alkilany ether of aliphatic or aromatic carboxylic acids, aliphatic ketone, aliphatic amine, aliphatic alcohol, a simple alkilany or cycloalkenyl ether or a mixture thereof, and any electron donor contains 2-20 carbon atoms. Among these electron donors are preferred simple alkalemia and cycloalkyl esters containing 2-20 carbon atoms; dialkyl-, diaryl - and alkylacrylate containing 3-20 carbon atoms; and complex Alki the new, CNS and alkylalkoxysilane esters of alkyl - and arylcarboxylic acids containing 2-20 carbon atoms. The most preferred electron donor is tetragidrofuran. Other examples of suitable electron donors include methylformate, ethyl acetate, butyl acetate, simple, ethyl ether, dioxane, simple di-n-propyl ether, simple disutility ether, ethanol, 1-butanol, ethyl formate, methyl acetate, ationist, ethylene carbonate resulting, tetrahydropyran and ethylpropane.

Although at the beginning of the reaction is used an excess of electron donor to obtain a product of the reaction of compounds of titanium and an electron donor, the resulting reaction product contains from about 1 to about 20 moles of electron donor per one mol of titanium compounds and preferably from about 1 to about 10 moles of electron donor per one mol of titanium compounds.

The precursors of catalysts can be activated to become catalysts. Activator catalyst precursor used at the stage of partial pre-activation may be a single compound or a mixture of two different compounds. Each connection can have the formula M(Rn)X(3-n), where M stands for Al or In; each X independently denotes chlorine, bromine or iodine; each R independently denotes a saturated aliphatic hydrocarbon radical containing 1-14 carbon atoms, p is and the condition, that when M stands for Al, n is 1-3, and when M means that n is 0-1,5. Examples of the radical R include methyl, ethyl, n-butyl, isobutyl, n-hexyl and n-octyl. When M stands for aluminum, n may be equal to 1, 1,5, 2 and 3. When M stands for boron, n can be 0, 1 or 1.5. Preferred activators include chloride diethylamine, triethylamine, tri-n-hexylamine, chloride dimethylamine and tri-n-octylamine. Particularly preferred activators are: subsequent mixture of chloride diethylamine and tri-n-hexylamine; subsequent mixture of chloride diethylamine and triethylamine; and either chloride diethylamine, or tri-n-hexylamine.

Partial activation of the catalyst precursor perform before the introduction of the catalyst precursor into the reactor. Partially activated catalyst may act as a catalyst of polymerization, containing very low and commercially unacceptable performance. To achieve maximum catalyst activity is required for full activation in the reactor for polymerization by adding socializaton.

In accordance with the preferred mode of operation (sometimes defined as built-in (in-line) system recovery) catalyst precursor is introduced into the supply tank With a suspension of hydrocarbon-based solvents is I; the suspension is served in a static mixer located downstream immediately after the entry opening activator, where specified, the suspension is mixed with an activator; the mixture is then served in the second static mixer located downstream immediately after the second hole to enter activator, where the mixture is mixed with the second activator. Static mixers can be arranged vertically. Acceptable mixing can be performed in a static mixer Kenics™ length 2 ft (32 elements). This mixer with low consumption operates on the principle of continuous flow separation and change of direction of flow in a circular diagram in accordance with the direction of flow in the pipe attached to the mixer. Depending on the activator interaction of the activator with the catalyst precursor may take some time. This process occurs in the area of temporary stay, which may consist of either lengthening the pipe for feeding the suspension or of the isolation tank that holds the thread. In the area of temporary stay can be both an activator, only one activator or activators in General may not be available depending on the rate of interaction of the activator with the catalyst precursor.

The entire mixture is then fed into the reactor, in this case in the first reactor, where the full activation of socializaton. Partial activation typically occurs at a temperature in the range of from about 10 to about 60°C., preferably from about 30 to about 45°C. the Molar ratio of each activator catalyst precursor to the electron donor can be from about 0.1:1 to about 0.6:1. The numerator and the denominator in the above relations represent, respectively, the total number of activators and the total number of electron donors used in this process.

The molar ratio of activator to titanium can be in the range from about 0.1:1 to about 8:1, preferably in the range of from about 1:1 to about 5:1. The hydrocarbon used for the formation of a suspension, may be any aliphatic or aromatic uglevodoroy, not containing air and moisture, which does not interact with the composition of the catalyst precursor and activator of the catalyst, catalyst precursor, activators of the catalyst precursor and socialization.

Since many of the final polymer products are of practical use in food packaging, aromatic hydrocarbons are not preferred suspendium solvent. Hydrocarbon suspendisse solvent is usual to choose from hydrogenated mineral oils or naphthenic oils with a relatively high viscosity, to minimize the precipitation of the solid catalyst particles in the flow lines and similar equipment, although with appropriate technological solution as suspendida solvents it is possible to use solvents with low viscosity, such as isopentane, hexane and heptane. These solvents are not particularly preferred because of the additional difficulties associated with the use as the catalyst easily settling of a suspension with a lower viscosity. The viscosity of the hydrocarbon suspending solvent is sufficiently low, so the suspension can be pumped into the machine pre-activation and then to the reactor for polymerization. Preferred solvents are aliphatic hydrocarbons with a viscosity of more than about 50 centipoise (cps), in particular more than about 100 cps and less than about 5000 cps. Especially preferred solvents are naphthenic mineral oils, such oils as the series kaydol" food mineral oil supplied by Witco under the trademark Kaydol®, Hydrobrite 380 and Hydrobrite 550.

Socialization, which is usually acetalization based hydrocellulose may be represented by the formula, R3Al or R2AlX, where R is independently mean alkyl, cycloalkyl, aryl or water is od; at least one radical R is hydrocarbon; and two or three of the radicals R can be joined to form heterocyclic structures. Each radical R, which is hydrocarbonyl radical may contain 1-20 carbon atoms, preferably 1-10 carbon atoms. X is halogen, preferably chlorine, bromine or iodine. Examples of compounds hydrocellulose include triisobutylaluminum, tri-n-hexylamine, hydride diisobutylaluminum, hydride dihexylfluorene, diisobutylaluminium, isobutylmethylxanthine, trimethylaluminum, triethylaluminum, Tripropylamine, triisopropanolamine, tri-n-butylamine, trioctylamine, tridecylamine, riddellii, tribenzylamine, triphenylamine, trinitroluene, tricholorethylene, chloride dibutylamine, chloride diethylamine, chloride diisobutylaluminum and sesquichloride ethylaluminum. Socialization enter in sufficient quantity to achieve atomic relations added socializaton Al:Ti in the range from about 10:1 to about 100:1, preferably higher than about 20:1 to about 50:1 Al:Ti. The specified number should be sufficient for full activation of the catalyst precursor.

The use of media is junk. However, in cases where it is desirable to use the catalyst precursor is and on the media, a preferred carrier is silica. Other acceptable carriers are inorganic oxides, such as aluminum phosphate, aluminum oxide, mixtures of silicon dioxide/aluminum oxide, silicon dioxide, modified alumoorganic connection, such as triethylaluminium, and silicon dioxide, modified diethylzinc. A typical carrier is a solid, porous material in the form of particles, essentially not involved in the polymerization reaction. The specified media used in the form of a dry powder with an average particle size of from about 10 to about 250 microns, preferably from about 30 to about 100 microns; a surface area equal to at least 200 m2per gram, preferably at least about 250 m2per gram; and a pore size equal to at least about 100 angstroms, preferably at least about 200 angstroms. The media is usually used in an amount to provide from about 0.1 to about 1.0 millimoles of titanium per gram of the carrier, preferably from about 0.4 to about 0.9 millimoles of titanium per gram of the carrier.

Media-based silicon oxide can be impregnated with the above catalyst precursor, mixing the catalyst precursor and the silica gel in solvent-electron donor or another solvent with subsequent removal is receiving solvent under reduced pressure. The obtained solid catalyst was then transformed using the above-described aliphatic hydrocarbon freely in the current suspension that can be served in the equipment pump in liquid form. The precursors of catalysts, such as described in U.S. patent No. 5290745 and in the application for European patent No. 771820, especially suitable for use in the method according to the present invention when introduced into the hydrocarbon slurry in the out-of tolerance condition.

As indicated above, the catalyst precursor is partially to activate polymerization. Activation is performed in the reactor with the help of socializaton. Socialization preferably added to the reactor for polymerization separately in pure form or in the form of a solution in an inert solvent, such as isopentane, simultaneously with the filing of ethylene.

In one embodiment of the invention in a single reactor using the catalyst of the second type on the basis of chromium, although the use of this catalyst is not limited to one reactor and it can be used in two or more series-connected reactors.

In this area known polyethylene, polymerized using catalysts based on chromium, and methods for their preparation. Such methods include polymerization in the gas phase, in solution phase and in the phase of the suspension. the special interest for the present invention are polymers, obtained by polymerization in the gas phase using a catalyst based on chromium and, in particular, the catalyst based on titaniumand chromium.

Acceptable catalysts are chromium compound (VI) (usually in the form of oxide) on a refractory oxide carrier with a large surface area. As the media usually use amorphous microspherical silica, aluminosilicate, titanosilicate or lumotast. The specified catalyst is produced by activation of chromiferous media at temperatures of 400-1000°C. in a dry oxygen-containing atmosphere. Before activating usually add these modifiers, as titanium and fluoride.

The catalysts are usually obtained using commercially available silicon dioxide, to which is added a source of chromium. The media on the basis of silicon dioxide can be processed complex ether titanium (usually use tetraisopropyl titanium or tetraethoxy titanium) after deposition or before the deposition of compounds of Cr. Carrier pre-dried at a temperature of about 150-200°C. to remove adsorbed water. The titanate may be added in the form of a solution to a suspension of silicon dioxide in isopentane or directly into the fluidized bed media. Adding to the suspension last dried. Connection Cr, can turn into Cr+6, advance, and the e is added to the media. Then the media turned into an active catalyst by calcination in air at temperatures up to 1000°C.

During activation, the titanium is converted into the surface oxide of a specific type. The chromium compound (usually acetate chromium (III)) is converted to the oxide of Cr+6a particular type. In the activation process can also be added fluorinating agents for selective destruction of some of the pores in the media, resulting in a change in molecular weight of the catalyst. Before applying the activated catalyst may also be treated with reducing agents, such as carbon monoxide in the fluidized bed, or other reducing agents, such as aluminiumgie, bialkali, liteally and the like.

Catalysts of this type are described in many patents, such as WO 2004094489, EP 0640625, US 4100105, and found in them the links. All of these patents are fully incorporated in the present description by reference. For example, an acceptable catalyst is a chromium-titanium catalyst on the carrier (or a catalyst based on titaniumand chromium oxide), which has a non-spherical or irregular in shape and characterized by a wide distribution of particle sizes, with at least 70% of the pores have a diameter of from about 200 to 500 angstroms. Such complex catalyst on socialemail to be activated by heating in the presence of oxygen at a temperature of from about 850°C. to the sintering temperature. Catalysts containing Cr+6that is similar to that described in U.S. patent No. 6022933, also suitable for use in the present invention. The referenced patent is fully incorporated into the present description by reference.

DESCRIPTION of the SPECIFIC CATALYST

FOR COMPOSITIONS IN the FORM of a MIXTURE of COMPONENTS

To obtain a catalyst precursor on the basis of trichloride titanium first prepare a solution of magnesium chloride and trichloride titanium in tetrahydrofuran. The whole process is carried out in a nitrogen atmosphere (less than 5 parts per million of N2O).

The tank is injected tetrahydrofuran (THF)containing less than 200 parts per million of N2O. Analyzing the degree of humidity and add triethylaluminium sufficient for interaction with water. THF is heated to 50°C and add the granulated metallic magnesium and titanium tetrachloride. The titanium tetrachloride is added in a quantity sufficient to form a solution of titanium (Ti) with a concentration of 0.09-0.10 millimoles/gram of solution. Magnesium metal is added in a molar ratio to the titanium tetrachloride 0.5:1. The titanium tetrachloride is added in for about half an hour.

The mixture is continuously stirred. The temperature of the support is equal to about 70°C., carrying out heat for about four hours. At the end of this lane is an ode to time add essentially anhydrous magnesium dichloride to the concentration of Mg in solution, equal to 0,45-0,60 millimoles/gram of solution. The mixture continue to heat, stirring, at 70°C for eight hours. Then the mixture (solution) was filtered through a filter with a mesh size of 100 microns to remove undissolved magnesium dichloride and unreacted magnesium.

To the above mixture for about two hours add essentially hydrophobic colloidal silicon dioxide with a particle size in the range of 0.1-1 micron. The mixture is stirred using a turbine stirrer throughout the specified time and within a few hours after the end of the Appendix for the complete dispersion of silica in solution. Before adding colloidal silica solution can be cooled to about 35°C. as colloidal silicon dioxide using Cab-O-Sil TS610. Colloidal silicon dioxide is added in a quantity sufficient to achieve the overall content of Cab-O-Sil about 6 wt.%.

The resulting suspension is spray dried using a spray dryer with a closed cycle, equipped with a centrifugal atomizer. The speed centrifugal atomizer is adjusted to obtain catalyst particles with diameter D50. The inlet temperature of the drying gas is adjusted so as to obtain the desired final concentration of tetrahydrofuran in the precursor kata is Isadora. Typically, the inlet temperature is in the range of 120-165°C. the Scrubber spray dryer is at a temperature of from 0 to -10°C for capturing the evaporated solvent.

Dried by spraying the catalyst precursor contains 2-2 .5 wt.% Ti, 5.5 to 7 wt.% Mg and 22-30 wt.% THF. Particles of the catalyst precursor is mixed with mineral oil in an atmosphere of nitrogen in a tank equipped with a turbine stirrer, to obtain a suspension containing about 28 wt.% the solid catalyst precursor.

For a partial suspension activation of the catalyst during the pumping of the slurry pump to the reactor are added 50 wt.% solution of tri-n-hexylamine (TnHAl) in mineral oil. This mixture is kept in a tank of temporary stay for about 1-4 hours depending on the absolute velocity of the catalyst. The solution TnHAl used in a quantity sufficient to achieve the desired molar ratio of TnHAl on one mole of THF in the catalyst.

Then add 30 wt.% solution of chloride diethylamine (DEAC) in mineral oil and incubated the mixture into another vessel temporary stay within 1-4 hours depending on the absolute velocity of the catalyst. DEAC is used in a quantity sufficient to achieve the desired molar ratio of DEAC on one mole of THF in the catalyst is. Partially activated catalyst is then aged in the second tank of temporary stay, and fed into the reactor for polymerization, where he is fully activated by a finite number of socializaton.

As indicated above, the catalyst precursor is partially to activate polymerization. Activation is performed in the reactor with the help of socializaton. Socialization preferably added to the reactor for polymerization separately in pure form or in the form of a solution in an inert solvent, such as isopentane, simultaneously with the filing of ethylene.

The whole catalytic system, which includes the partially activated catalyst precursor and socialization, is introduced into the first reactor. The catalytic system that is partially activated catalyst precursor and socialization, mixed with the copolymer or homopolymer obtained in the first reactor, and the resulting mixture is transferred to the second reactor. As for the catalytic system, socialization may optionally be added to the second reactor from an external source.

The polymerization in each reactor is carried out in a gas phase in a continuous process in a fluidized bed, but the polymerization can also be in suspension or solution. For example, in U.S. patent No. 5844045, 5869575 and 6448341 described the copolymerization of e is Elena and C3-C20 alpha-olefins in solution using a homogeneous catalyst in at least one reactor and a heterogeneous catalyst in at least one other reactor. In U.S. patent No. 6566446 (Parikh et al.) and 6538070 (Cardwell et al.) described the copolymerization of ethylene with the use of homogeneous catalyst in two different reactors, in which the conditions of polymerization of the change order impact on catalytic activity. In all these cases, the reactors can operate in series or parallel. All of these patents are fully incorporated in this description by reference.

The composition can also be obtained by fractionation of heterochain copolymer of ethylene and alpha-olefin in the specific polymer fractions, each of which is characterized by a narrow distribution (i.e. branching) in the composition, the choice of the fraction having the desired properties, and mixing the selected fraction in an appropriate amount with another polyethylene. This method is not as efficient as the in situ copolymerization described in U.S. patent No. 5844045, 5869575 and 6448341, but can be used to obtain the compositions of the present invention. All of these patents are fully incorporated in the present description by reference.

Methods of polymerization are described in other patents, including U.S. patent No. 4076698 (Andersen et al.), 5977251 (Kao et al.) and WO 97/36942 (Kao et al.), which are fully incorporated into this description by reference is I.

The compositions of the present invention can also be obtained by any known method, including dry blending the individual components and then mixing in the melt or mix in the state, prior to the melt in a separate extruder (e.g., a Bunbury mixer, the mixer Haacke, internal mixer of Brabender or twin-screw extruder with the rotation of the augers in the same or opposite directions).

Copolymer of relatively low density are usually obtained in the first reactor. The mixture of polymer and active catalyst is preferably transferred from the first reactor to the second reactor by connecting the device using as the carrier medium nitrogen or recirculating gas from the second reactor. The copolymer is relatively high densities are in the second reactor. Alternatively, the copolymer of high density can be obtained in the first reactor, and a copolymer of low density can be obtained in the second reactor.

These compositions are characterized by a broad molecular weight distribution, which, as noted, can be defined as bimodal. A wide molecular mass distribution corresponds to the ratio Mw/Mn equal to from about 3 to about 10, preferably from about 3 to about 8. Mw means srednevekovoy molecular weight; Mn means srednei the gross molecular weight; and the ratio of Mw/Mn can be defined as the index polydispersity, which is a measure of the breadth of the molecular mass distribution.

DESCRIPTION the POLYMERIZATION REACTION

FOR COMPOSITIONS IN the FORM of a MIXTURE of COMPONENTS

The mass ratio of the copolymer obtained in the reactor to obtain a polymer of low density, and the copolymer obtained in the reactor to obtain a polymer of high density may be from about 10:90 to about 90:10, preferably from about 20:80 to about 80:20, most preferably from about 20-30: 80-70. This ratio is also known as the mixing ratio. Catalytic system based on transition metal, including socialization, ethylene, alpha-olefin, and optionally hydrogen, is continuously fed to the first reactor; the mixture of the polymer/active catalyst is continuously transferred from the first reactor to the second reactor; ethylene and optionally an alpha-olefin and hydrogen and socialization served continuously to the second reactor. The final product is continuously removed from the second reactor. In accordance with the preferred mode of operation of the separate portions of the product from the first reactor is moved in the second reactor using differential pressure created by the compressor recycle gas. Particularly suitable is a system similar to that described in U.S. patent No. 462952.

The pressure is approximately the same in the first and second reactors. Depending on the specific method used to move the mixture of polymer and catalyst from the first reactor to the second reactor, the pressure in the second reactor may be higher or lower than in the first reactor. If the pressure in the second reactor is lower, the pressure difference can be used to facilitate the movement of the mixture of polymer and catalyst from reactor 1 to reactor 2. If the pressure in the second reactor is higher, the pressure drop in the compressor circulating gas can be used as a driving force to move the polymer.

Pressure, i.e. the total pressure in the reactor can range from about 200 to about 500 psig, preferably from about 280 to about 450 psig. The partial pressure of ethylene in the first reactor may be from about 10 to about 150 psig, preferably from about 20 to about 80 psig. The partial pressure of ethylene in the second reactor is set based on the number of copolymer, which should be obtained in this reactor to achieve the above-mentioned ratio of the mixture components. It is known that increasing the partial pressure of ethylene in the first reactor causes an increase in the partial pressure of ethylene in the second reactor. The balance of the total pressure provided the W alpha-olefin, other than ethylene, and an inert gas such as nitrogen. Other inert hydrocarbons, in particular, the agent is induced condensation of, for example, isopentane, hexane, also contribute to the changes in the total pressure in the reactor depending on the steam pressure generated in the temperature and pressure in the reactor.

A typical reactor with a fluidized bed can be described as follows. Fluidized bed usually created from the same granular polymer, which must be obtained in the reactor. Thus, in the process of polymerization fluidized bed consists of the formed polymer particles, the growing polymer particles and catalyst particles fluidized gaseous components of the polymerization and modifying gaseous components introduced with volumetric or linear flow velocity sufficient to separate the particles into the fluid. Fluidizable gas includes initially supplied gas, a compensating gas and circulating (recycle) gas, i.e., the comonomers, and optionally modifiers and/or an inert carrier gas.

The main elements of the reaction system are the reactor, fluidized bed, the gas distribution plate, inlet and outlet piping, compressor, chiller recirculating gas and discharge system, p is oduct. In the reactor above the fluidized bed zone of clearing speed and in the fluidized bed is the reaction zone. Both zones are located above the gas distribution plate.

A typical reactor with a fluidized bed is described in U.S. patent No. 4482687. The streams of gaseous ethylene and other gaseous alpha-olefins and hydrogen, if used, preferably served by pipeline for recirculating gas pipeline for liquid alpha-olefins and solution socializaton. Liquid acetalization can be entered directly in the fluidized bed. Partially activated catalyst precursor is preferably introduced into the fluidized bed in the form of solids or suspensions in mineral oil. Activation is completed in the reactor using socializaton. The composition of the product can be changed by changing the molar relationship of the comonomers introduced into a fluidized bed. The product is continuously withdrawn from the reactor in the form of granules or particles with increasing the layer level in the polymerization process. The performance of the reactor is controlled by changing the feed rate of the catalyst and/or the partial pressure of ethylene in both reactors. The referenced patent is fully incorporated into the present description by reference.

By changing the molar ratio of hydrogen to catiline, it is possible to regulate the average molecular weight. The total number of alpha-olefins other than ethylene) can be up to 15 wt.% copolymer, and in the case of the use of the total number of alpha-olefin in the copolymer is preferably from about 1 to about 10 wt.% based on the weight of the copolymer.

The residence time of the mixture of reagents, including gaseous and liquid reactants, catalyst and polymer in each of the fluidized bed can be in the range from about 1 to about 12 hours and preferably in the range of from about 2 to about 5 hours.

The reactor can, if desired, to operate in condensing mode. Condensing mode is described in U.S. patent No. 4543399, 4588790 and 5352749. All of these patents are fully incorporated in the present description by reference.

The mixture can be made from components obtained in two independent reactors (which used the same or different catalysts), as a result of their subsequent mixing or in a single reactor with two compatible catalysts, which allow to obtain the required components in one set of conditions. In the second case, the catalysts can be submitted separately or together.

As mentioned above, the gaseous substances used in this process, you can enter the reactor as recycle gas. Recircula the respective gas can be defined as a mixture of gases, includes only the ethylene or ethylene and one or more alpha-olefins, preferably one or two alpha-olefins, are used as comonomers, and optionally one or more inert gases such as nitrogen (to create the desired pressure in the reactor), inert hydrocarbons and hydrogen. The alpha-olefins may include, for example, propylene, 1-butene, 1-hexene, 4-methyl-1-penten and 1-octene. Alpha-olefins usually contain not more than 12 carbon atoms, preferably 3-8 carbon atoms. Recircularii gas can also be called "the incoming gas or circulating gas."

As indicated above, the catalyst precursor is partially to activate polymerization. Activation is carried out in a reactor using socializaton. Socialization preferably added to the reactor for polymerization separately in pure form or in the form of a solution in an inert solvent, such as isopentane, simultaneously with the filing of ethylene.

The polymerization is carried out in a gas phase in a continuous process in a fluidized bed. The melt index (I2) is determined using a modified firm Dow method ASTM D-1238 at a temperature of 190°C. and a weight of 2.16 kg and expressed in grams/10 minutes or DG/minute. Flow index (I21,6) is determined using a modified firm Dow method ASTM D-1238 at a temperature of 190°C and wt is e of 21.6 kg and expressed in grams/10 minutes or DG/minute. The ratio of the melt flow is the ratio of flow index to melt index (I21,6/I2,16). The product removed from the reactor, can have a melt index equal to from about 0.02 to about 300 grams/10 minutes, preferably the melt index is in the range from about >0.04 to about 50 grams/10 minutes. The ratio of melt flow is in the range from about 20 to about 50, preferably in the range of from about 20 to about 35. The density of the polymer is equal at least to 0.900 g/cm3preferably 0,915-0,960 g/cm3still preferable 0,935-0,955 g/cm3and most preferably 0,940-0,950 g/cm3.

DETERMINATION of MOLECULAR MASS DISTRIBUTION

Molecular weight distribution polyethylenes determined using gel chromatography (GPC) in the high temperature chromatograph Waters 150°C, equipped with a differential Refractometer and three columns of mixed porosity. These columns are supplied by Polymer Laboratories, usually filled with material with a pore size equal to 103, 104, 105and 106Å. As a solvent used for 1, 2, 4-trichlorobenzene, from which 0.3 wt.% solutions of sample introduced into the column. A flow rate of approximately 1.0 ml/min, the working temperature of the device is approximately 140°C, and veliciraptor equal to about 100 microliters.

Molecular weight distribution in relation to the main chain of the polymer is calculated in accordance with the standards of narrow molecular weight distribution polystyrene (Polymer Laboratories) in combination with the volume of elution. Equivalent molecular weight polyethylene determined by using appropriate coefficients Brand-Hovinga for polyethylene and polystyrene (see Williams and Ward in Journal of Polymer Science, Polymer Letters, Vol. 6, p. 621, 1968) using the following equation:

MPE= a × (Mpolystyrene)b

In this equation a=0,4316 and b=1,0. Srednevekovoy molecular mass Mw, is calculated by the following formula: Mj=(Σ wi(Mij))jwhere wimean mass fraction of molecules with a molecular mass Mi, loireau from the GPC column in fraction i; j=1 when calculating Mwand j=-1 when calculating Mn. The new composition has a ratio of Mw/Mnthat is less than or equal to 3.3, preferably less than or equal to 3 and, in particular, is in the range from about 2.4 to about 3.

In the reactor, designed to obtain compositions in the form of a mixture of components, the molar ratio of alpha-olefin (if using) to ethylene can be in the range of from about 0.01:1 to about 0.8:1, preferably from about from 0.005:1 to about 0.25:1. The molar ratio of bodoro is and (if using) to ethylene can be in the range of from about 0,001:1 to about 2:1, preferably from about 0.05 to about 0.3:1. The working temperature may be equal to about 60-120°C., preferably about 80-110°C. it Should be noted that these relationships apply only to products hexene and not applicable to systems with two catalysts, which requires changes in the types of catalysts and conditions depending on the catalyst type.

Pressure, i.e. the total pressure in the reactor may be in the range of from about 200 to about 500 psig, preferably from about 280 to about 450 psig. The partial pressure of ethylene can be in the range of from about 10 to about 200 psig, preferably from about 60 to about 170 psi. The balance of the total pressure, there is an alpha olefin (if using) and an inert gas such as nitrogen. Other inert hydrocarbons, in particular, the agent is induced condensation of, for example, isopentane, hexane, also contribute to the changes in the total pressure in the reactor depending on the steam pressure generated in the temperature and pressure in the reactor. A typical reactor with a fluidized bed can be described as follows.

Fluidized bed usually created from the same granular polymer, which must be obtained in the reactor. Thus, in the process of polymerization fluidized bed which consists of the formed polymer particles, the growing polymer particles and catalyst particles fluidized gaseous components of the polymerization and modifying gaseous components introduced with volumetric or linear flow velocity sufficient to separate the particles into the fluid. Fluidizable gas includes initially supplied gas, a compensating gas and circulating (recycle) gas, i.e., the comonomers, and optionally modifiers and/or an inert carrier gas.

The main elements of the reaction system are the reactor, fluidized bed, the gas distribution plate, inlet and outlet piping, compressor, chiller recirculating gas and discharge system of the product. In the reactor above the fluidized bed zone of clearing speed and in the fluidized bed is the reaction zone. Both zones are located above the gas distribution plate.

A typical reactor with a fluidized bed is described in U.S. patent No. 4482687, which is fully incorporated into the present description by reference.

The streams of gaseous ethylene and other gaseous alpha-olefins (if using) and hydrogen (if used) are preferably served by pipeline for recirculating gas pipeline for liquid alpha-olefins (in case of their use is litvania). Activated catalyst precursor is preferably introduced into the fluidized bed in the form of solids or suspensions in mineral oil. The composition of the product can be changed by changing the molar relationship of the comonomers and hydrogen introduced into a fluidized bed, and relationships of various catalysts used in a single reactor. The product is continuously withdrawn from the reactor in the form of granules or particles with increasing the layer level in the polymerization process. The performance of the reactor is controlled by changing the feed rate of the catalyst and/or the partial pressure of ethylene.

By changing the molar ratio of hydrogen to ethylene and the temperature in the reactor, it is possible to regulate the average molecular weight. By changing the molar ratio of alpha-olefin to ethylene, it is possible to adjust the density of the polymer.

The total number of alpha-olefins other than ethylene) can be up to 15 wt.% copolymer, and in the case of the use of the total number of alpha-olefin in the copolymer is preferably from about 1 to about 12 wt.% based on the weight of the copolymer.

The residence time of the mixture of reagents, including gaseous and liquid reactants, catalyst and polymer in the fluidized bed can be in the range from about 1 to about 12 hours and preferably in the range of from about 1.5 to about 5 hours.

The reactor m which may, if desired, to operate in condensing mode. Condensing mode is described in U.S. patent No. 4543399, 4588790 and 5352749.

The polymer can be ekstradiroval in a conventional extruder adapted for this purpose. Extruders and extrusion methods described in U.S. patent No. 4814135, 4857600, 5076988 and 5153382. All of these patents is hereby incorporated into this description by reference.

The conditions created in the reactor for a product in the form of a mixture of components:

ProductThe polymer InPolymer And
The temperature in the reactor, °C88102
The pressure in the reactor, pounds/square inch315320
SRR, pounds/square inch100155
H2/S2(molar ratio yield strength)0,1400,220
With6/S2(molar ratio yield strength)0,1500,013
Al/Ti (molar ratio)4050
I2g/10 minutes1,04,4
Density, g/cm30,9180,952

Closures of compositions of the present invention can be manufactured by methods described, for example, in U.S. patent No. 6139931 (Finkelstein et al.), 5598940 (Finkelstein et al.), 6382445 (candless), 5000992 (Kelch), 4744478, 4744478 (Hahn), 4807772 (Schloss) and 4846362 (Schloss). All of these patents are fully incorporated in the present description by reference.

Gaskets, if used in accordance with the present invention, can be manufactured by methods described in U.S. patent No. 4984703 (Burzynski), 5137164 (Bayer) and 4872573 (Jonhson et al.). All of these patents are fully incorporated in the present description by reference.

With regard to the relative concentrations of the components of the mixture, in one embodiment of the invention, the mixture can include:

(A) from about 10 to about 90 wt.% polyethylene with a density of from about 0,947 to about 0,962 g/cm3, a melt index from about 1 to about 10 g/10 minutes, preferably from about 2 to about 8 g/10 minutes, more preferably from about 3 to about 7 g/10 minutes;

(B) from about 90 to about 10 wt.% polyethylene with a density of from about 0,912 to about 0,932 g/cm3 , a melt index from about 0.25 to about 6 g/10 minutes, preferably from about 0.5 to about 4 g/10 minutes, more preferably from about 0.75 to about 3 g/10 minutes; and

(C) 0-6 wt.% additives selected from the group including color enhancers, lubricants, fillers, pigments, antioxidants and substances to improve the processing properties, preferably in an amount of 0.01-3 wt.%, most preferably in the amount of 0.015 to 0.5 wt.%;

where the difference between the densities of the components (a) and (b) (∆D=D(A)D(B)) is equal to or greater than 0.03 g/cm3.

In the scope of the present invention also includes an intermediate amount, for example, when component a is about 40-85 wt.% and a component In approximately 15-60 wt.% or when component a is about 65-80 wt.% and component comprises about 20-35 wt.%. Professionals in this field should be clear that the relative amounts of components a and b, expressed in percent, if necessary, can be changed.

DESCRIPTION of the SPECIFIC CATALYST AND POLYMERIZATION CONDITIONS

FOR one-component POLYMERIC COMPOSITION

One-component adenomegaly polymer is produced as follows: in accordance with the method of the polymers in the gas phase in the reactor with a fluidized bed of ethylene and comonomer-1-hexene enter into contact with the catalytic system, including the surrounding catalytically active chromium or a complex of chromium and titanium on the carrier of the refractory oxide, in which at least 70% of the total volume of pores has a diameter of about 200-500 angstroms, and activate the specified complex medium, heating it in the presence of oxygen at a temperature of from about 600°C. to the sintering temperature of the complex on the media.

Oxygen can be injected into the reactor for polymerization at a molar ratio of About2/S2up to 250 molar parts per billion to increase the melt index and density of the polymer, which, in turn, requires a larger number of co monomer to achieve equivalent density. U.S. patent No. 6022933, which provides a detailed description of this method, fully incorporated into the present description by reference. The polymer is usually characterized by a melt index (MI) in the range of 0,3-1,2 (modified by the company Dow method ASTM D-1238, condition E) and a density (ASTM D-1505) within 935-955 g/m3. You can use 1-hexene, 1-octene, 4-methyl-1-penten or other alpha-olefin comonomers with molecular weight more than of propylene. The sample for evaluation was selected copolymer of ethylene and hexene with a melt index of 0.8 and a density of 945. When tested as closures for bottles and soda water all the required properties have been demonstrated after adding 200 parts per million Carbowax™ 400, which improves the color to the desired degree. To sample floor the measure as a seed, you don't need to add 1000 ppm HPN™ 68. To improve the workability and durability for a long period of time, add the usual antioxidants.

In combination with the polymers described in the present description of the invention may be used various additives. Additives can be used to improve various properties (ESCR, color, taste, etc). For example, polyethylene (such as a copolymer of ethylene and hexene)obtained with the use of chrome catalyst is characterized by a much better resistance to cracking in environmental conditions (ESCR) and color when added to the polymerization process connection dialkylzinc, such as diethylzinc, in a molar ratio of Zn:Cr of 10:1 to 80:1, more preferably from 50:1 to 70:1.

The conditions created in the reactor for one-component product catalyzed by chromium catalyst.

Conditions in the reactor
Units
The molar ratio of O2/S2280The mole. parts per billion
The temperature of the fluidized bed103,7°C
The molar ratio of concentrations With6/S20,0040mol/mol
The molar ratio of yield strength With6/S20,020mol/mol
Mass gas flow rate2,53ft/s
Molar concentration of isopentane2,7mol.%
The performance of catalyst3800lb/lb
Bulk density of the upper fluidized bed (FBD)15,5lb/ft3
Bulk density of the lower fluidized bed (FBD)17,7lb/ft3
The mass of fluidized bed132,2pounds/hour
Performance64,8pounds/hour
PropertyThe average is e Units
The melt index, as determined by the modified firm Dow method ASTM D-1238, condition E0,86DG/min
The melt flow index determined by the modified firm Dow method ASTM D-1238, condition Fto 59.6DG/min
The ratio of the melt flow (I21/I2)68,7no
Density, ASTM D-7920,9453g/cm3
The average particle size, ASTM D-19210,021inches

Into the reactor continuously serves a catalytic system based on transition metal, including activated catalyst precursor and ethylene, and optionally one or more alpha-olefin comonomers and hydrogen. The resulting polyethylene remove the semi-continuous method.

SUPPLEMENTS

The composition is added to a mixture of antioxidants includes, but is not limited to:

390 parts per million disneylandhotel (known as Weston™ 399);

750 parts per million of zinc stearate;

<> 510 parts per million octadecyl-3,5-di-tert-butyl-4-hydroxy-hydrocinnamate;

210 parts per million of zinc oxide.

Professionals in this field must be known for many other stabilizers, ensuring stabilization of the polymer, as appropriate to the application.

To reduce surface defects and fracture extrusion flow during extrusion and direct compression can be used forecasting additive to improve the processing properties, such as Dynamar™ FX-5911, in an amount up to about 500 parts per million.

SUPPLEMENTS FOR single-component PRODUCT CATALYZED by CHROMIUM

Four possible composition of antioxidant supplements for the mixture include, but are not limited to:

Part 1

350 parts per million Igranox™ 3114 (I-3114)

200 parts per million Carbowax™ 400 (C-400)

Part 2

350 parts per million Igranox™ 1010 (I-1010)

200 parts per million Carbowax™ 400

Part 3

350 parts per million Igranox™ 3114

400 ppm Irgafos™ 168 (I-168)

200 parts per million Carbowax™ 400

Part 4

350 parts per million Igranox™ 1010

400 ppm Irgafos™ 168

200 parts per million Carbowax™ 400

The person skilled in the art should be understood that one or more additives can be used in combination. In certain embodiments of the invention, one or the number of additives can range from about 0.01 to about 6 wt.% of the composition. In other embodiments the invention, the additive may be present in amounts of from 0.01 to about 3 wt.%. In other embodiments the invention, the additives can be present in an amount of 0.015 to 0.5 wt.%. However, in other embodiments, implementation of the present invention can be used for other quantities of additives while maintaining the required characteristics.

As for the technological process, the specialists in this area should be clear that in certain conditions can form polymeric gels. This may complicate the processing of high molecular weight polymers. One solution to this problem is the melting of the composition (which can represent the above mixture, passing the molten mixture through one or more consecutive active sit and subsequent execution of extrusion or granulation. In one embodiment, the invention can be used in coarse-mesh sieve (hole size of 20-40 mesh.). In alternative embodiments of the invention can be used fine sieve (hole size 250-325 mesh.). In another embodiment, the invention can be used in combination of fine and coarse sieves. This process may be improved through the application of computer m is melirovanie flux dynamics (CFD). CFD can be used to create screens, which can eliminate the risk of falling drops of polymer gel on a coarse wire sieve, which can cause the splitting of drops. Professionals in this field should be clear that it is possible to use other filters (such as fabric filters with zero holes" (i.e. a simple Dutch linen, cotton twill and so on).

TEST METHODS

With13NMR spectroscopy

The distribution of short-chained structure and content of comonomers is measured by the method of13C-NMR spectroscopy, is described in the publication Randall, Rev. Macromol. Chem. Chys., C29 (2&3), pp. 285-297 and in U.S. patent No. 5292845, which is incorporated into this description by reference. The samples were obtained by adding approximately 3 g of a mixture of tetrachlorethane-d2/orthodichlorobenzene (50/50), which corresponds to 0.025 M in chromium acetylacetonate (relaxer)to 0.4 g sample in a 10 mm tube for NMR spectroscopy. The samples are dissolved and homogenized by heating the tube and its contents to 150°C. the Data were obtained in the NMR spectrometer 400 MHz JEOL Eclipse, the corresponding resonant frequency13With equal 100,6 MHz. Measured parameters were chosen so as to ensure that data quantification13With the presence of the relaxer. Data were obtained with the use of the article is obirvani junction 1H, 4000 transitions in a single data file, a relaxation delay of 4.7 seconds, the time for data collection 1.3 seconds, spectrum width 24200 Hz, file size 64000 data points and the heating head probe 130°C. the Spectra were compared with the peak of the methylene at 30 ppm, the Results were calculated by the method of ASTM D5017-91.

CRYSTAF (analytical fractionation method of crystallization) was performed and determined in accordance with the following publications.

An experimental and numerical study on crystallization analysis fractionation (crystaf). Anantawaraskul, Siripon; Soares, Joao B. P.; Wood-Adams, Paula M. Department of Chemical Engineering, McGill University, Montreal, QC, Can. Macromolecular Symposia (2004), 206(Polymer Reaction Engineering V), 57-68.

13C NMR, GPC, and DSC study on a propylene-ethylene-1-butene terpolymer fractionated by temperature rising elution fractionation. Zhang, Yu-Dong; Gou, Qing-Qiang; Wang, Jun; Wu, Chang-Jiang; Qiao, Jin-Liang. Beijing Research Institute of Chemical Industry. SINOPEC, Beijing, Peop. Rep. China. Polymer Journal (Tokyo, Japan) (2003), 35(7), 551-559.

Effect of molecular weight and average comonomer content on the crystallization analysis fractionation (Crystaf) of ethylene a-olefin copolymers. Anantawaraskul, Siripon; Soares, Joao B. P.; Wood-Adams, Paula M. Benjamin Monrabal. Department of Chemical Engineering, McGill University, Montreal, QC, Can. Polymer (2003), 44(8), 2393-2401.

Ethylene/1-hexene copolymers synthesized unit with a single-site catalyst: Crystallization analysis fractionation, modeling, and reactivity ratio estimation. Sarzotti, Deborah M.; Soares, Joao B.P.; Penlidis, Alexander. Institute for Polymer Research, Department of Chemical Engineering, University of Waterloo, Waterloo, ON, Can. Journal of Polymer Science, Part B: Polymer Physics (2002), 40(23), 2595-2611.

COLOR. Measured by test method ASTM D-1925-88. YI = the degree of yellowing.

MECHANICAL PROPERTIES AT STRETCHING THE INSTITUTE. These properties were measured by the method of ASTM-D638 using samples of type IV obtained in accordance with ASTM D 4976 in the form of a disk.

THE MELT INDEX. Measured by the modified firm Dow method ASTM D-1238, condition (190, 2.16) and (190, 21.6).

MFR = M/MI2 or modified by the company Dow method ASTM D-1238 (190, 2.16/190, 21.6).

The DENSITY. Was measured by the method ASTM D-792.

THE MODULUS OF ELASTICITY IN BENDING. Was measured by the method of ASTM D-790 using samples obtained in accordance with ASTM D 4976 in the form of a disk.

SENSITIVITY TO NOTCH IZOD. Was measured by the method of ASTM D-256 using samples obtained in accordance with STM D-4976 in the form of a disk.

THE AVERAGE PARTICLE SIZE. ASTM D-1921.

EXAMPLES

Examples 1-3. The properties of the composition in the form of a mixture of components

Researched blend of polymers a and b with a ratio of 3:1 (75 wt.% polymer and 25 wt.% polymer C). The results obtained in examples 2 and 3, as presented in the following tables.

Example 1 (third mix) polymer A:polymer (75%:25%)
The average densityg/cm30,9452
ESCR*-100% igepal CO 630
1st breakwatch121
2nd breakwatch160
3rd breakwatch208
4-th gapwatch215
5-th gapwatch256
6-th gapwatch329
7-th gapwatch377
8-th gapwatchI have not measured
9-th gapwatchI have not measured
10-th gapwatch496
The testing timewatch496
F50watchwatch283,5
Melt index - I2g/10 minutes3,13
Tensile strength - Molded samples according to ASTM D 4976The average thicknessinches0,067
The average widthinches0,25
The average strain at the yield point%5,868
The average yield strengthpounds/ square inch3271,5

*Resistance to cracking in environmental conditions

Polymer a is a copolymer of ethylene and 1-hexene with a melt index (I23.

The polymer In = a copolymer of ethylene and 1-hexene with a melt index (I2approximately 1 g/10 minutes, Mw/Mn of about 4 and a density of about 0,918 g/cm3.

Example 1Example 2Example 3
The mixture with the ratio of polymer:polymer And 25:75The mixture with the ratio of 20:80The mixture with the ratio of 30:70
Test conditions#UnitsThe initial mixtureThe second mixturePolymer: polymer AndPolymer: polymer And
DensityASTM D-792g/cm30,9440,945I have not measuredI have not measured
I2 Modified by Dow ASTM D-1238 (190/2,16)g/10 minutes3,42,9I have not measuredI have not measured
ESCRASTM D-1693, condition B, 10% igepal50% probability of failure (hours)168>172>172>172
ASTM D-1693, condition B, 100% igepal50% probability of failure (hours)I have not measured>172>172>172
Tensile strengthYield strengthpsi31603100I have not measuredI have not measured
The elongation at the yield point%6,27,7I have not measured I have not measured
BendThe tangent modulus of elasticitypsiI have not measured162000I have not measuredI have not measured
1% secant moduluspsiI have not measured131000I have not measuredI have not measured
2% secant moduluspsiI have not measured110000I have not measuredI have not measured
Sensitivity to notch IzodASTM D-256Futon/ inchI have not measured7,7I have not measuredI have not measured
DSKTm°CI have not measured130 I have not measuredI have not measured
The fraction of high density Atref (%)72,4
Fraction blowing Atref (%)12,4
Fraction Atref SCBD (%)15,2
Only100,0
Soluble fraction Crystaf (%)3,0

Example 4. Composition based on a polymer

Example 4Competitive product
Samsung C430A
Supplements350 ppm Irganox 3114 and 200 parts per million Carbowax 400
PropertiesThe ASTM testTarget consumer
MI2 (g/10 minutes)D-1238, condition E (modified by the company Dow)0,691,65
Density ASTM (g/cm3)D-7920,94650,9574
ESCR F50(hours), 10% igepal at 50°CD-1693, condition18761,7
Re-determining ESCR F 50(hours), 10% igepal at 50°CD-1693, condition59,7
ESCR F50(hours), 100% igepal at 50°CD-1693, condition>80324874,3
Re-determining ESCR F50(hours), 100% igepal at 50°CD-1693, condition>8057,1
Tensile strength (pounds/ square inch)D-638 using a sample of type IV22173014
% elongationD-638 using a sample of type IV543935
The yield point (lbs/psi)D-638 using a sample of type IV3000-400034824345
% elongation at the yield point D-638 using a sample of type IV6,67,7
The fraction of high density Atref (%)Method Dow78,285,4
Fraction blowing Atref (%)Method Dow8,37,2
Fraction SCBD
Atref (%)
Method Dow13,57,4
Only100,0100,0
Soluble fraction Crystaf (%)Method Dow2,91,4
ColorASTM
D-1925-88
YI = -2,47
TasteMethod DowProduct region which gives a smaller taste compared to the unmodified control product

The color of the polymer according to example 4. All products b, D, F and H, containing 200 parts per million Carbowax 400, have the good taste. YI = the degree of yellowing.

MedicationAdditive in parts per millionThe average degree of yellowingThe standard deviationThe values of the degree of yellowing
I-1010C-400I-168I-3114123
A3500,970,0420,941,020,96
B350200-2,370,020-2,35 -2,39-2,37
C3504000,780,0520,840,750,75
D350200400-2,350,042-2,38-2,36-2,30
E3501,560,0461,521,611,55
F200350-2,470,026-2,49-2,44-2,48
G 4003501,680,0461,691,631,72
H200400350-2,280,020-2,30-2,28-2,26

Professionals in this field should be clear that it is possible to use any known method of manufacturing closures of compounds described in the present description of the invention.

Certain embodiments of the present invention relate to polymeric compositions having the desired properties. In particular, in certain embodiments of the invention polymer compositions obtained according to the present invention, have the preferred properties for use as a sealing means, in comparison with previously known compositions.

1. The molding composition intended for the manufacture of closures, containing:
(A) from 10 to 90 wt.% copolymer of ethylene and 1-hexene with a density in the range from 0,947 on the 0,962 g/cm 3and melt index, determined at 190°C. and a load of 21.6 kg in accordance with ASTM D-1238 of from 2 to 8 g/10 min,
(B) from 90 to 10 wt.% copolymer of ethylene and 1-hexene with a density in the range from 0,912 to 0,932 g/cm3and melt index, determined at 190°C. and a load of 21.6 kg in accordance with ASTM D-1238 of from 0.25 to 6 g/10 min and
(C) from 0.01 to 3 wt.%, at least one additive selected from the group comprising lubricants, fillers, pigments, antioxidants and substances to improve the processing properties,
moreover, the difference between the densities of the components (a) and (b) (∆D=D(a)-D(in)) is equal to or greater than 0.03 g/cm3and the content of the co monomer is 1-hexene in the composition is from 0.5 to 4 wt.% calculated on the total weight of the composition, and the composition has a resistance to cracking in environmental conditions (ESCR) 100% igepal in accordance with ASTM D-1693 method In more than 80 hours

2. The composition according to claim 1, characterized in that it contains a component (A) in an amount of from 40 to 85 wt.% and component (C) in an amount of from 15 to 60 wt.%.

3. The composition according to claim 2, characterized in that it contains a component (A) from 65 to 80 wt.% and component (C) in an amount of from 20 to 35 wt.%.

4. The composition according to claim 1, characterized in that it contains component (C) in an amount of between 0.015 to 0.5 wt.%.

5. The composition according to claim 1, characterized in that it contains less than 80 wt.% the high fraction is lotnosti.

6. The composition according to claim 1, characterized in that it is characterized by the content of soluble fractions over 1.75% (determined by CRYSTAF method).

7. The composition according to claim 1, characterized in that it has an ESCR index, determined in accordance with ASTM D-1693 method, using 100% of igepal exceeding 150 hours

8. The composition according to claim 1, characterized in that it has an index of polydispersity is the ratio Mw/Mn is from 3 to 20.

9. Sealing means containing molding composition according to claims 1-8.



 

Same patents:

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SUBSTANCE: invention relates to polyethylene and articles made by injection moulding polyethylene. Polyethylene contains homopolymers of ethylene and/or copolymers with ethylene with molecular weight distribution Mw/Mn between 3 and 30, density of 0.945 - 0.965 g/cm3, average molecular weight Mw between 50000 g/mol and 200000 g/mol, high-load melt index (HLMI) between 10 and 300 g/10 min. The polymer contains 0.1-15 branches/1000 carbon atoms, where 1-15 wt % polyethylene with the highest molecular weight has degree of branching greater than 1 branch of side chains with length greater than CH3/1000 carbon atoms.The polyethylene is obtained using a catalyst composition which contains at least two different polymerisation catalysts, where A) is at least one hafnocene-based polymerisation catalyst (A2), and B) is at least one polymerisation catalyst based on an iron component, having a tridentate ligand which contains at least two ortho-, ortho-disubstituted aryl radicals (B). The disclosed polyethylene can be subjected to processing treatment on standard injection moulding apparatus.

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9 cl, 2 tbl, 2 ex

FIELD: chemistry.

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

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5 cl, 4 tbl, 6 ex

FIELD: chemistry.

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

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

22 cl, 1 tbl, 16 ex

FIELD: chemistry.

SUBSTANCE: resin has melt index MI5 from 0.40 to 0.70 g/10 min and contains from 47 to 52 wt % low-molecular polyethylene fraction and from 48 to 53 wt % high-molecular polyethylene fraction, where the high-molecular polyethylene fraction includes a copolymer of ethylene and 1-hexene and 1-octene.

EFFECT: improved hydrostatic properties.

5 cl, 3 tbl, 6 ex

FIELD: chemistry.

SUBSTANCE: invention relates to polyethylene mixed compositions, intended for film manufacturing, which include two or more different ethylene polymers, each of which has different degree of complexity of long chain branching. Polyethylene composition is practically linear and has average index of branching constituting 0.85 or less. In addition, composition has density 0.935 g/cm3 or less, dullness - 10% or less and stability to falling load impact - 100g/mm or more, determined according to ASTM D-1709 methodology.

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15 cl, 1 dwg, 5 tbl, 5 ex

FIELD: chemistry.

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

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19 cl, 1 tbl, 2 dwg, 12 ex

Polyethylene films // 2349611

FIELD: packing industry.

SUBSTANCE: invention relates to polyethylene films and first of all to bimodal polyethylene compositions designed for the production of films with low impurities content and increased manufacturability. The film contains polyethylene composition with the density of 0.940-0.970 g/cm3 and melt index value (I21) measured according to ASTM-D-1238-F technique 190°C/21.6 kg, from 4 to 20 dg/min. The polyethylene composition contains a high-molecular component with the average molecular weight more than 50000 and a low-molecular component with the average molecular weight less than 50000.

EFFECT: definite combination of the composition polymer characteristics meets the commercial requirements to the production of polyethylene films suitable for manufacturing the films by moulding, blow formation and other methods, the films are characterised by improved operational parameters along with high film quality that is revealed by low gel fraction content and simultaneous retention of strength, flexibility and impact resistance values.

28 cl, 7 dwg, 6 tbl, 12 ex

FIELD: chemistry.

SUBSTANCE: invented here is a copolymer of ethylene with α-olefins, with molecular weight distribution Mw/Mn from 1 to 8, density from 0.85 to 0.94 g/cm3 , molecular weight Mn from 10000 g/mol to 4000000 g/mol, not less than 50% distribution width index of the composition, and at least, bimodal distribution of branching of side chains. Branching of side chains in maximums of separate peaks of distribution of branching of side chains in all cases is larger than 5 CH3/1000 carbon atoms. Ethylene copolymers are obtained in the presence of a catalyst system, comprising at least, one monocyclopentadienyl complex A) or A'), optionally an organic or inorganic substrate B), one ore more activating compounds C) and optionally one or more compounds, containing group 1, 2 or 13 metals of the periodic system D).

EFFECT: invented compounds have bimodal distribution of short-chain branching and narrow molecular weight distribution, as well as high impact property.

11 cl, 1 tbl, 3 ex, 2 dwg

FIELD: chemistry.

SUBSTANCE: present invention pertains to a method of obtaining a resin composition. Description is given of the method of obtaining a resin composition through mixture in a molten mass of 100 weight parts of cyclic olefin polymer (A), whose glass transition temperature ranges from 60 and 200°C, and 1-150 weight parts of elastic polymer (B), with glass transition temperature 0°C or lower. Part of the cyclic olefin polymer (A) is first mixed in a molten mass with elastic polymer (B) and 0.001-1 weight parts of radical polymerisation initiator (C). The remaining cyclic olefin polymer (A) is then added and mixed in the molten mass. The ratio of the quantity of cyclic olefin polymer (A), initially added, to the quantity of the same polymer added later (initially added/added later) ranges from 1:99 to 70:30. Cyclic olefin polymer (A) is divided into two parts and added separately twice, such that, the mixture with a cross-linked structure can be diluted with cyclic olefin polymer (A), without a cross-linked structure. As a result, increase in the viscosity of the molten resin composition can be prevented.

EFFECT: good abrasion resistance and good moulding properties of the molten mass.

15 cl, 1 tbl, 4 ex

FIELD: chemistry.

SUBSTANCE: film is made from polymer mixture, which contains (wt %): 50-90% composition of the ethylene polymer and 10-50% polymer component on ethylene basis, having a density in the range from 0.9 to 0.930 g/ml and molten flow-rate till 4 g/10 min. Composition of the ethylene polymer contains a recurring unit, obtained from an ester, selected from (1) ethylene-unsaturated organic monomer in the form of esters unsaturated C3-C20 monobasic carboxylic acids and C1-C24 univalent aliphatic or alicyclic alcohols, (2) vinyl esters saturated C2-C18 carboxylic acids, where the content of esters is in the range from 2.5-8 wt %. Composition of the ethylene polymer has a density in the range from 0.920 to 0.94 g/ml. Stretchable packing film has a relation between the value of tear resistance longitudinally and the vale of tear resistance transversely, which exceeds 0.3 and the value of ultimate tensile strength lengthwise 30% in the range from 6.5 to 15 N.

EFFECT: effective application in the capacity of stretching adhesive covers in various operations in linking packing and wrapping.

6 cl, 3 tbl, 17 ex

FIELD: chemistry.

SUBSTANCE: invention relates to bands made from polyethylene, specifically to synthetic turf made from such bands. The pigmented band contains 75-99.5 wt % non-pigmented polyethylene having density between 928 and 940 kg/m3 and melt flow index MI2 not less than 0.3 g/10 min and up to 25 wt % pigmented polyethylene. Total amount of pigment in the band is not less than 0.5 wt %.

EFFECT: pigmented band for making synthetic turf has better balance between softness and elasticity compared to that of existing types of turf.

10 cl, 2 tbl, 2 ex

FIELD: chemistry.

SUBSTANCE: invention relates to polyethylene and articles made by injection moulding polyethylene. Polyethylene contains homopolymers of ethylene and/or copolymers with ethylene with molecular weight distribution Mw/Mn between 3 and 30, density of 0.945 - 0.965 g/cm3, average molecular weight Mw between 50000 g/mol and 200000 g/mol, high-load melt index (HLMI) between 10 and 300 g/10 min. The polymer contains 0.1-15 branches/1000 carbon atoms, where 1-15 wt % polyethylene with the highest molecular weight has degree of branching greater than 1 branch of side chains with length greater than CH3/1000 carbon atoms.The polyethylene is obtained using a catalyst composition which contains at least two different polymerisation catalysts, where A) is at least one hafnocene-based polymerisation catalyst (A2), and B) is at least one polymerisation catalyst based on an iron component, having a tridentate ligand which contains at least two ortho-, ortho-disubstituted aryl radicals (B). The disclosed polyethylene can be subjected to processing treatment on standard injection moulding apparatus.

EFFECT: articles obtained through injection moulding is uniform and can further be improved by increasing rate of injection moulding or high melting point.

9 cl, 2 tbl, 2 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a method of preparing a polyethylene based composition capable of peroxide cross-linking, which is meant for making articles for various purposes at the end of the cross-linking process, e.g. cable insulation, machine housings, semiconductor protective screens and tubes. The method involves pre-mixing a liquid organic peroxide, a liquid antioxidant and a liquid light stabiliser. The obtained liquid mixture is then added to polyethylene powder at room temperature and stirred intensely, preferably at mixer rotational speed of 800-1500 rpm. The light stabiliser used is at least one liquid sterically hindered amine.

EFFECT: using simple technology to prepare a peroxide cross-linked polyethylene composition, which can be stored for up to four or more days at room temperature with preservation of its activity.

4 cl, 2 tbl, 7 ex

FIELD: chemistry.

SUBSTANCE: method involves mixing nanofiller with binder, mechanical activation of the obtained mixture and final moulding of the mixture. The powdered filler and binder undergo combined preliminary mechanical activation to obtain a concentrate. The concentrate is a powdered mixture of components with ratio binder: filler equal to 50:50. Further, the obtained concentrate is mixed with binder in amount of 100 pts. wt binder per 0.1-2.0 pts. wt concentrate to obtain a second mixture. This mixture undergoes traditional mixture in a bead mill for a period of time sufficient for obtaining a homogeneous mixture. The powdered mixture is then hot-moulded at pressure and temperature at which the mixture turns into a fluid. Further, the mixture is kept under these conditions until complete solidification. The binder used is powdered polypropylene.

EFFECT: method enables to obtain antifriction material, characterised by high strength properties and wear resistance, elasticity and low brittleness.

1 cl, 7 ex, 6 dwg, 1 tbl

FIELD: construction engineering.

SUBSTANCE: moulding powder for making a porous sintered body contains polyethylene of molecular weight of polyethylene within approximately 600000 g/mol to 2700000 g/mol as specified in ASTM 4020. The average diametre of powder particles is within approximately more than 80 mcm to 1000 mcm. Polyethylene has the powder bulk density within approximately 0.10 to 0.29g/cm3. Herewith the porous sintered body has the bond strength 0.7 MPa and higher, and the pressure differential 6 Mbar or lower in a sample of diametre 140 mm and thickness 6.2-6.5 mm at the air current 7.5 m3/hour.

EFFECT: products show excellent porosity and high durability.

17 cl, 3 dwg, 5 tbl, 5 ex

FIELD: chemistry.

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

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

2 cl, 4 ex, 2 tbl

FIELD: process engineering.

SUBSTANCE: proposed invention can be used in machine building for fabricating articles based on extremely-macromolecular polyethylene of varying purpose. Proposed method comprises preliminary cold forming from initial extremely-macromolecular polyethylene powder with subsequent moulding at 190°C and specific pressure of 10 to 15 MPa. Heated obtained article is placed into injection mold wherein laminating layer of polyoxymethylene is injected at 230°C. Now, the article is cooled.

EFFECT: reduced weight, higher hardness and wear resistance.

3 dwg, 1 tbl

FIELD: chemistry.

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

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

3 cl, 1 tbl, 3 ex

FIELD: chemistry.

SUBSTANCE: invention can be used for making polymer pipes meant for carrying water and cables. The composition contains soot, finely dispersed silicon dioxide, secondary high-pressure polyethylene and secondary low-pressure polyethylene.

EFFECT: combination of components in a defined ratio increases mechanical strength, reduces cost of the polymer composition and partially solves the problem of recycling polethylene wastes.

8 ex, 2 tbl

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: pipeline insulation from heat-retention polyolefin foam.

SUBSTANCE: invention relates to method for production of physically foamed heat-retention polyolefin foam and expanded material made from the same. Polyolefin foam is obtained by extrusion of expanded material composition containing (mass %): metallocene polyethylene 77-92; antipyrene 5-10; cell stabilizer 3-8; and other additives 0-5 % using physical foaming agent. Flexible expanded material of present invention has wide-range application, in particular it is useful as insulator for thin and/or twisted pipelines. Forasmuch foam is obtained using physical foaming agents and is not chemically cross-linked it may be reprocessed for reutilization.

EFFECT: flexible heat-retention polyolefin foam of improved quality.

10 cl, 1 ex

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