JPH03296511A - Preparation of ethylene-pentene-1 copolymer - Google Patents

Abstract

PURPOSE:To prepare the title copolymer which can be formed into a film excellent in the balance between impact strength and unsealability by copolymerizing ethylene with pentene-1 in suspension under specific conditions in such a manner that the resulting copolymer satisfies specific requirements. CONSTITUTION:Ethylene and pentene-1 are copolymerized in suspension at 0-120 deg.C in the presence of a catalyst contg. a solid catalyst component in such a manner that 30wt.% or higher of the resulting copolymer does not dissolve into the liq. medium and that the resulting copolymer satisfies the requirements that the density is 0.90-96g/cm<3>; that the structural units derived from pentene-1 accounts for 2-25wt.%; and that in a 40mum - thick cast film obtd. by casting the copolymer, the ratio (RS) of impact strength to tear strength in the direction of taking out the film satisfies the formula (wherein MFR is the melt flow rate of the copolymer; and d is its density).

Description

[Detailed description of the invention]

[00011

TECHNICAL FIELD OF THE INVENTION The present invention relates to a method for producing an ethylene-pentene-1 copolymer, and more specifically to a novel ethylene-pentene-1 copolymer that, when formed into a film, has a good balance between impact resistance and unsealability. The present invention relates to a method for producing a copolymer. [0002] [Technical Background of the Invention 1] Linear low-density polyethylene (LLDPE), which is a copolymer of ethylene and α-olefin, is more difficult to form into a film than high-pressure low-density polyethylene (LDPE). Because of its excellent impact strength, it is widely used as a raw material for film forming. [0003] In order to produce the above ethylene/α-olefin copolymer, butene-1 or an α-olefin having 6 or more carbon atoms is used as the α-olefin. [0004] Films obtained from ethylene-butene-1 copolymers have moderate tear strength and are therefore excellent in unsealability, but have a problem in that they have somewhat poor impact strength. [0005] On the other hand, a film obtained from a copolymer of ethylene and an α-olefin having 6 or more carbon atoms has poor impact strength, but the tear strength is higher than required, so the film cannot be easily formed. There was a problem in that it did not tear and therefore had poor opening properties. [0006]Therefore, there is a strong desire for an ethylene/α-olefin copolymer that can provide a film with excellent impact strength and also excellent unsealability. The present inventors conducted intensive research to obtain the above-mentioned ethylene/α-olefin copolymer, and found that an ethylene/pentene-1 copolymer having specific physical properties obtained by copolymerizing ethylene and pentene-1 The present invention was completed based on the discovery that the polymer has excellent impact strength as well as excellent unsealability when formed into a film. [0007] Object of the Invention The present invention has been made in view of the above-mentioned prior art, and is an ethylene-pentene film that can provide a film that has excellent impact strength and is also easy to open. 1 copolymer. [0008]

[Summary of the invention]

The method for producing an ethylene/pentene-1 copolymer according to the present invention comprises copolymerizing ethylene and pentene-1 in a suspended state in the presence of a catalyst containing a solid catalyst component. In some cases, ethylene
A method for producing a pentene-1 copolymer, the method comprising producing the copolymer in a state where 30% by weight or more of the copolymer does not dissolve into the liquid medium and at a polymerization temperature range of 0 to 120°C. The copolymer obtained is characterized in that it satisfies the following requirements (A) to (C). (A) Density measured by ASTM D 1505E is 0.90 to 0.96 g/cm3, and the constituent unit derived from ethylene pentene-1 is 5 to 25% by weight.
(C) The ratio (R3) of the impact strength of a 40 μm thick film obtained by molding the copolymer into a cast film and the tear strength in the pulling direction of the film satisfies the following formula. R3≧-201ogMFR-1000d+968(
In the formula, MFR represents the melt flow rate of the copolymer, and d represents the density of the copolymer. ) According to the method for producing an ethylene/pentene-1 copolymer according to the present invention, since ethylene and pentene-1 are copolymerized under specific conditions, the obtained ethylene/pentene-1
The copolymer satisfies specific requirements and has an excellent balance between impact resistance and openability when formed into a film. [0009] The method for producing the ethylene/pentene-1 copolymer according to the present invention will be specifically explained below. [00101 The method for producing an ethylene/pentene-1 copolymer according to the present invention is characterized by copolymerizing ethylene and pentene-1 under specific conditions. In the copolymerization reaction, for example, the following olefin polymerization catalysts can be used. [0011] A magnesium compound in a state of a magnesium compound or a hydrocarbon solvent solution of a magnesium compound A solid magnesium-aluminum complex having an R2 group (RI and R2 are each a hydrocarbon group), (A2) from a mixture containing a magnesium compound and an electron donor R10 group or ROH-containing solid magnesium compound (B) obtained from a liquid magnesium compound formed or a liquid magnesium compound formed from a solution of a magnesium compound in a hydrocarbon solvent, or any of the above (A1), periodic Table of Law Groups 1 to 1I
Solid magnesium-aluminum complex containing R'0 group and R3 group < R3 is a hydrocarbon group) obtained by reacting a group I metal with an organometallic compound (C), from the above (A) or (A2) Contains at least 10% of titanium atoms in a low valence state obtained by reacting a selected hydrocarbon-insoluble solid magnesium aluminum complex with a tetravalent titanium compound, and /Mg (weight ratio) of 1 to 15 solid titanium catalyst component for olefin polymerization [A]
An example of an olefin polymerization catalyst includes: and an organoaluminum compound catalyst component [B]. [0012] This olefin polymerization catalyst and a reaction system using this catalyst will be explained below, but the production method according to the present invention can be implemented not only with these catalyst systems or reaction systems but also with other catalyst systems or reaction systems. It is possible to carry out the method by selecting appropriate conditions even in the case of a system. [0013] The above [A] solid titanium catalyst component for olefin polymerization typically uses a liquid magnesium compound as a starting material, and an organic aluminum compound and an RO group (R1 is a hydrocarbon group) forming compound. A low-valent titanium compound obtained by reacting a magnesium-aluminum complex having an R10 group and a hydrocarbon group with a tetravalent titanium compound, which is obtained by reacting the R10 group with a tetravalent titanium compound. It is a supported component of titanium. [0014] The liquid magnesium compound may be, for example, a magnesium compound dissolved in a hydrocarbon, an electron donor, or a mixture thereof, or may be a molten magnesium compound. Magnesium compounds used for this purpose include magnesium halides such as magnesium chloride, magnesium bromide, magnesium iodide, and magnesium fluoride; methoxymagnesium chloride, ethoxymagnesium chloride, isopropoxymagnesium chloride, butoxymagnesium chloride, and octoxymagnesium chloride. Alkoxymagnesium halides such as magnesium chloride; allyloxymagnesium halides such as phenoxymagnesium chloride, methylphenoxymagnesium chloride; ethoxymagnesium,
isopropoxymagnesium, butoxymagnesium,
Examples include alkoxymagnesiums such as octoxymagnesium; allyloxymagnesiums such as phenoxymagnesium and dimethylphenoxymagnesium; magnesium carboxylates such as magnesium laurate and magnesium stearate. Moreover, the magnesium compound is a complex compound with other metals,
It may be a composite compound or a mixture with other metal compounds. Furthermore, a mixture of two or more of these compounds may be used. [0015] g (OR5) 2 (X is a halogen, R5 is a hydrocarbon group) is magnesium 0genide, alkoxymagnesium halide, allyloxymagnesium halide, alkoxymagnesium, allyloxymagnesium, preferably Halogen-containing magnesium compounds, especially magnesium chloride, alkoxymagnesium chloride, allyloxymagnesium chloride, particularly preferably magnesium chloride. [0016] These magnesium compounds in a liquid state are preferably dissolved in a hydrocarbon solvent, an electron donor, or a mixture thereof in which the magnesium compound is soluble. Hydrocarbon solvents used for this purpose include pentane,
Aliphatic hydrocarbons such as hexane, heptane, octane, decane, dodecane, tetradecane, kerosene; alicyclic hydrocarbons such as cyclopentane, methylcyclopentane, cyclohexane, methylcyclohexane, cyclooctane, cyclohexene; benzenetoluene, xylene,
Examples include aromatic hydrocarbons such as ethylbenzene, cumene, and cymene; halogenated hydrocarbons such as dichloroethane, dichloropropane, trichloroethylene, carbon tetrachloride, and chlorobenzene. [0017] In order to obtain a magnesium compound dissolved in a hydrocarbon solvent, it is possible to obtain a magnesium compound dissolved in a hydrocarbon solvent by simply mixing the two (for example, using Mg(OR)2 having 6 to 20 carbon atoms as R5), although it depends on the type of the compound and the solvent. a method of mixing and heating, an electron donor soluble in the magnesium compound, such as an alcohol, an aldehyde, an amine, a carboxylic acid, any mixture thereof, and a mixture of these with other electron donors, etc. It is possible to adopt a method of making the material exist and heating it as necessary. For example, in the case of dissolving a halogen-containing magnesium compound in a hydrocarbon solvent using alcohol, it is preferable that the alcohol per mole, about 1 mole or more, preferably about 1 to about 20 moles, particularly preferably about 1.5 to about 1 mole
It is used in a range of 2 moles. When using aliphatic hydrocarbons and/or alicyclic hydrocarbons as hydrocarbons,
If alcohol is used in the above ratio, especially alcohol having 6 or more carbon atoms, about 1 mol or more, preferably about 1.5 mol or more, per 1 mol of halogen-containing magnesium compound, the total amount of alcohol used can be reduced. It is preferable because it is possible to solubilize the halogen-containing magnesium compound even with a small amount of the amount, and the catalyst component has a good shape. in this case,
For example, if only an alcohol having 5 or fewer carbon atoms is used, approximately 15 moles or more of the alcohol is required per mole of the halogen-containing magnesium compound, and the shape of the catalyst is also inferior to that of the above system. On the other hand, if an aromatic hydrocarbon is used as the hydrocarbon, the halogen-containing magnesium compound can be solubilized with the amount of alcohol used as described above, regardless of the type of alcohol. [0018] The contact between the halogen-containing magnesium compound and the alcohol is preferably carried out in a hydrocarbon medium, usually at room temperature or above, depending on the type thereof, at about 65°C or above, preferably at about 80 to 300°C, -layer suitable This is carried out by contacting at a temperature of about 100 to about 200° C. for about 15 minutes to about 5 hours, more preferably about 30 minutes to about 2 hours. [0019] Suitable alcohols are alcohols having 6 or more carbon atoms, such as 2-methylpentanol, 2-ethylbutanol, n-heptatool, n-octatool,
2-ethylhexanol, decanol, dodecanol,
Aliphatic alcohols such as tetradecyl alcohol, undecenol, oleyl alcohol, stearyl alcohol, alicyclic alcohols such as cyclohexanol, methylcyclohexanol, benzyl alcohol, methylbenzyl alcohol, isopropylbenzyl alcohol, α-methylbenzyl alcohol, α , aromatic alcohols such as α-dimethylbenzyl alcohol, and aliphatic alcohols containing alkoxy groups such as n-butyl cellosolve and 1-butoxy-2-propatol. Examples of other alcohols include methanol, ethanol, propatool, butanol, ethylene glycol,
Examples include alcohols having 5 or less carbon atoms such as methylcarpitol. [0020] A solution of an electron donor other than alcohol can also be used as the solution of the magnesium compound. Preferred examples of electron donors used for such purposes are amine aldehydes and carboxylic acids. Examples of other electron donors are phenols, ketones, esters, ethers, amides, acid anhydrides, acid halides, nitriles, isocyanates, and the like. The quantitative relationship and dissolution temperature when producing these solutions are generally the same as when dissolving in a hydrocarbon solvent using an electron donor, but - quantitatively, it is necessary to maintain a high temperature, so the catalyst From the viewpoint of preparation, it is easier to obtain a product with high performance by using one dissolved in a hydrocarbon. [0021] Another example of a liquid magnesium compound is a melt of a magnesium compound, such as a melt of a complex of a magnesium halide and an electron donor, such as those exemplified above. . The preferred one is
This is a melt of a magnesium halide/alcohol complex represented by MgX2.nROH (R1 is a hydrocarbon group, n is a positive number). [0022] Next, the RO group and R
Producing a solid magnesium-aluminum complex having 3 groups (or R2 groups) (R1R2R3 is a hydrocarbon group, and R3 (or R2) is a reducing group directly bonded to magnesium or aluminum) This section describes how to do this. Here, the magnesium-aluminum complex has the empirical formula: Mg8AlbR8 (or R3o)
(OR1) dX28 (X2 is halogen, 2a+3b=c
+d+e), and in some cases, other compounds or electron donors may be further bonded. Preferably Al/
Mg (atomic ratio) is 0.05 to 1, preferably 0.0
8-0.5, more preferably 0.12-0.3, R1
0 group is preferably 0.5 per part by weight of magnesium
~15 parts by weight, more preferably 1 to 10 parts by weight, even more preferably 2 to 6 parts by weight, hydrocarbon group R (or R3)
is preferably 0.01 to 0 per 1 atom of magnesium.
．． 5 equivalents, preferably 0.03 to 0.3 equivalents, more preferably 0.05 to 0.2 equivalents, and X2/Mg (atomic ratio) is preferably 1 to 3, preferably 1.5 to 3. 2
．． It is 5. [0023] Next, a specific example of manufacturing the magnesium-aluminum composite will be described. A specific method for producing a magnesium-aluminum composite includes a method of directly producing a composite by bringing a liquid magnesium compound into contact with an organic aluminum compound. [0024] It is necessary to use a compound having an RO group or a compound semi-producing an RO group, such as an R10H group, and a halogen compound as at least one of the liquid magnesium compound and the organic aluminum compound. [0025] Reaction of alkyl aluminum compound with Mg
A solution containing (OR5) trialkylaluminum, trialkenylaluminum such as triisoprenylaluminum, dialkylaluminum aralkylaluminum such as diethylaluminum ethoxide, dibutylaluminum butoxide, dialkylaluminum halide such as diethylaluminum chloride, dibutylaluminum chloride, diethylaluminum bromide, Partially halogenated alkyl aluminum sesquihalides like ethyl aluminum sesquichloride, butyl aluminum sesquichloride, ethyl aluminum sesquipromide, alkyl aluminum cybarides like ethyl aluminum dichloride, propyl aluminum dichloride, butyl aluminum dipromide etc. Partially hydrogenated alkyl aluminum, dialkyl aluminum hydride such as diethylaluminum hydride, dibutyl aluminum hydride, alkyl aluminum halide such as ethyl aluminum dicdride, probyl aluminum dihydride, ethyl aluminum ethoxy chloride , butylaluminum butoxychloride, ethylaluminum ethoxybromide, and other partially alkoxylated and halogenated alkylaluminum. [0027] The alkylaluminum halide is selected from the halogen-containing alkylaluminum compounds listed above. Not only is there a method in which a liquid magnesium compound and an alkyl aluminum compound are brought into contact with each other in one step, but also a method in which a part of the alkyl aluminum magnesium compound in a liquid magnesium compound is brought into contact with an alkyl aluminum compound that is the same as or different from the previous one. It also includes multi-step contact such as the above.Usually, the latter multi-step contact makes it easier to control the particle size and amount of organic groups of the magnesium compound, and also provides high performance. It is easy to obtain a catalyst. [0028] When carrying out such a multi-stage contact, the solid magnesium compound can be separated from the liquid part after the first stage of contact is completed, and then the next reaction can proceed.Final. In particular, it is preferable that the composition of the solid magnesium-aluminum composite falls within the above-mentioned range. For this purpose, it is preferable to use an appropriate amount of the alkyl aluminum compound in the contact. For example, to describe a method of contacting an alkylaluminum compound in two steps, when a solution using alcohol is used as the liquid magnesium compound, at least 0 R2-Al bond of the alkyl aluminum compound per equivalent of the hydroxyl group of the alcohol is used. It is preferable to use it in a ratio of .5 equivalent or more. On the other hand, if the amount of the alkyl aluminum compound used is too large, the shape of the generated particles will deteriorate,
Granular catalyst may not be obtained. Therefore, usually 0.5 to 10 equivalents of R2-Al bond, preferably 0.7 to 5 equivalents, more preferably 0.9 to 3 equivalents, particularly preferably 1.0 to 2 equivalents of R2-Al bond per equivalent of hydroxyl group of alcohol.
It is preferable to use it within an equivalent range. [0029] At this time, it is preferable to use trialkylaluminum as the alkylaluminum compound because a well-shaped catalyst can be easily obtained. Other preferred organoaluminum compounds include dialkyl aluminum halides, dialkyl aluminum hydrides, dialkyl aluminum alkoxides, and the like. [00303] In the contact between the liquid magnesium compound and the alkyl aluminum compound, the concentration of the magnesium compound in the liquid is preferably about 0.005 to 2 mol/l, particularly about 0.05 to 1 mol/l. [0031] Precipitation of the magnesium compound occurs, for example, when an alkylaluminium compound reacts with alcohol to generate an insoluble magnesium compound. If the magnesium compound is rapidly precipitated, it may be difficult to obtain particles with excellent particle shape, moderate particle size, and narrow particle size distribution, and the catalyst carrier may not be optimal for slurry polymerization. For this reason, it is preferable to precipitate the solid by performing the contact under mild conditions, and it is desirable to consider the contact temperature, the amount or rate of addition of the alkyl aluminum compound during solid precipitation, the concentration of each component, etc. [0032] For the reasons mentioned above, the liquid magnesium compound and the organoaluminum compound are brought into contact at a temperature range of -50 to 100°C, particularly -30 to 50°C, and then at a temperature of 0 to 20°C.
It is preferred to carry out the reaction at a temperature range of 0°C, preferably 40-150°C. As already mentioned, after forming the solid magnesium compound, the temperature when further catalytically reacting the alkylaluminum compound is 0 to 250°C;
In particular, a temperature of 20 to 130°C is preferred. [0033] In any case, it is preferable that the contact and reaction conditions are such that the RO group and R2 group of the solid magnesium-aluminum composite are within the ranges described above, and that the particle size of the composite is 1 μm or more, In particular, it is preferable to select so that the particle size is 5 μm or more and 100 μm or less, the geometric standard deviation is in the range of 1.0 to 2.0, and the particle shape is granular. [0034] As the compound to be contacted after forming the solid magnesium compound, instead of the alkyl aluminum compound, organic metal compounds of Groups I to II of the periodic table other than aluminum, such as alkyl lithium and alkyl magnesium, may be used. A magnesium-aluminum composite can be produced using halides, dialkylmagnesium, etc. [0035] Another method for producing a solid magnesium-aluminum composite is a method using the aforementioned process element, hydrogen chloride, silicon tetrachloride, or a halogenated hydrocarbon, or before using an alkyl aluminum compound, or This method uses a halogenating agent after use. These methods are useful as an alternative to methods using alkyl aluminum halides. [0036] The method of using a halogenating agent before using the alkylaluminum compound is to remove R from a liquid magnesium compound.
It is useful as a means for producing an OH solid magnesium compound containing ○ group or R'OH. The desired solid magnesium-aluminum composite can be produced by reacting the solid magnesium compound with the alkyl aluminum compound. For example, the reaction between a solution containing MgX2 hydrogen and a halogenating agent,
Alternatively, the above-mentioned solid magnesium compound can be produced by the reaction of Mg(OR)2 in a hydrocarbon solvent and a halogenating agent. May form complex compounds. In this method, the reaction between a solid magnesium compound and an alkyl aluminum compound, in which halogen is usually used in an equivalent ratio of about 1 to 1000 equivalents per 1 atom of magnesium in the magnesium compound, is carried out after the multi-step preparation method described above. It can be carried out according to the step method. [0037] Another method for obtaining the solid magnesium compound as described above is a method in which MgX2 in a molten state is cooled and solidified. [0038] In any of the above methods, the solid magnesium compound has a particle size of 1 μm or more, particularly 5 μm or more and 10
0 μm or less, particle size distribution with geometric standard deviation of 1.0 to 2.0
Preferably, the precipitation conditions are selected so that the particles have a spherical or granular shape. [0039] In the solid magnesium-aluminum composite obtained as described above, the internal volume of the closed system sufficiently substituted with dry nitrogen was 20%.
About 0.5 g of a solid magnesium-aluminum composite is added to a 0 ml flask, and about 25 ml of water is added dropwise to this while stirring. After about 20 minutes, the gas phase and aqueous phase in the flask are extracted with a microsyringe, and the alkane concentration is measured by gas chromatography. Multiply these concentration values by the volumes of the gas phase and aqueous phase, add them together to determine the total amount of generated alkanes, and use this total amount to determine the amount of alkane present in the complex. It can be considered as the total amount of alkanes produced by the reaction of groups with water, and can be considered as the amount of reducing groups present in the complex. [0040] Ti/
Mg (atomic ratio) is less than 1, preferably 0.01 to 0.7
Particularly preferably, the usage ratio is 0.04 to 0.5.
A solid titanium compound is prepared by contacting the titanium compound with a titanium compound having a titanium content of 10% or less. At least a portion of the supported titanium is reduced to a low valence, for example, trivalent. [0041] There are various tetravalent titanium compounds used for preparing the solid titanium catalyst component [A], but usually Ti(OR)gX
4. -g (R is a hydrocarbon group, X is a halogen atom, 0≦
Examples include tetravalent titanium compounds represented by g≦4). More specifically, T1Cl TiBr, Ti
Tetrahalogenated titanium such as I4; 4ゝ4 Ti(OCH3)C13, Ti(OC2H5)C13, Ti(On-C, iH9) Cl3, Ti(OC
2H5) Br3, trihalogenated alkoxytitanium such as Ti(0-1so-C4H9)Br3; Ti(OCH3)2C
12, Ti (On-C4H9)2 C12, Ti(OC2
Dihalogenated dialkoxytitanium such as H5)2Br2; Ti(OCH3)3C1, Ti(OC2H5)3C1, Ti(On-C4H9)3C11 Monohalogenated trialkoxytitanium such as Ti(OC2H5)3Br; Ti(OCH3)4 , Ti(OC2H5)4, Ti(On-C4H9)4, Ti(O-1SO-C4H9)4, and tetraalkoxytitanium such as Ti(0-2-ethylhexyl). Among these, titanium tetrahalides and alkoxytitanium trihalides are particularly preferred, and alkoxytitanium trihalides are particularly preferred. [0042] The catalytic reaction between the solid magnesium-aluminum composite and the titanium compound is preferably carried out in a hydrocarbon medium. In contact with the titanium compound, the final solid titanium catalyst component has a weight ratio of R70 groups/Mg (R7 is a hydrocarbon group) of 0.5 to 15, preferably 1 to 10, particularly preferably 2 to 6. Conditions are selected that provide a range. Here, the R70 group is derived from the R10 group in the solid magnesium-aluminum composite or from the titanium compound. If the R70 group is less than the above range, slurry polymerization will be poor in ethylene copolymerization, and the composition distribution of the resulting copolymer will not be sufficiently narrow. Furthermore, if the R70 group is present in an amount exceeding the above range, the activity tends to decrease. [0043] In order to adjust the R70 group in the solid titanium catalyst component to the above range, the type of titanium compound, the amount used, the contact temperature, etc. may be adjusted. The contact temperature of titanium compounds is usually 0~
The temperature is about 200°C, preferably about 20 to 100°C. [0044] In forming the solid product as described above, porous inorganic and/or semi-organic compounds may coexist,
A method may be adopted in which the solid product is thereby deposited on the surface of these compounds. At this time, the porous compound may be brought into preliminary contact with a liquid magnesium compound in advance, and brought into contact with a liquid titanium compound while containing and retaining the liquid magnesium compound. Examples of these porous compounds include silica, alumina, magnesia, polyolefin, and products of these treated with halogen-containing compounds. Furthermore, when using porous compounds containing aluminum, magnesium, RO groups, etc., which are essential components of the present catalyst, deviations from the above-mentioned preferred catalyst composition may occur. [0045] t, u, v>0. Xl is a halogen) and optionally contains other compounds, such as silicon compounds. Here, Ti/Mg (atomic ratio) is usually 0.01 to 0.5
, preferably 0.02-0.3, Al/Mg (atomic ratio) 0.05-1, preferably 0.08-0.5, more preferably 0.12-0.3, X1/Mg (atomic ratio) ratio)
is 1.5-3, preferably 2-2.5, OR7/Mg(
weight ratio) is 0.5 to 15, preferably 1 to 10, particularly preferably 2 to 6, and the specific surface area is 50 to 1000 m2/g
, preferably 150 to 500 m2/g. 10 to 100% of the total Ti has a lower valence than Ti4+. [0046] The solid titanium catalyst component [A] can be used in combination with the organoaluminum compound catalyst component [B] for olefin polymerization. The organoaluminum compound catalyst component [B] can be selected from the alkyl aluminum compounds listed above as those that can be used in the preparation of the solid titanium catalyst component. [0047] Among these, trialkyl aluminum, alkyl aluminum halide, or a mixture thereof is preferred. Olefin polymerization using an olefin polymerization catalyst containing solid [A] acid component and [B] acid component as described above is not limited to copolymerization of ethylene and pentene-1, but also copolymerization of ethylene and pentene-1. It is also possible to copolymerize three or more components by making a small amount of other α-olefin or polyene present in the reaction system. Other α-olefins other than ethylene and pentene-1 that can be used in this copolymerization include 2-methylpropylene, 1-butene, 1-hexene, 4-methyl-1-pentene, 3-methyl-1 -pentene, 1-octene, nonene-1, decene-1, undecene-1, dodecene-1,
Examples include. Examples of the polyene include butadiene isoprene, 1,4-hexadiene, dicyclopentadiene, 5-ethylidene-2-norbornene, and the like. [0048] The above catalyst for olefin polymerization is particularly useful when copolymerizing ethylene and pentene-1 by a suspension polymerization method. The polymerization reaction can be carried out either batchwise or continuously. [0049] The solid titanium catalyst component [A] may be used in powder form or suspended in a hydrocarbon medium or olefin, and the organoaluminum compound catalyst component [B] may be diluted or undiluted. Supplied directly into the polymerization system. [00501 Furthermore, the molecular weight of the polymer can be controlled by supplying hydrogen into the polymerization system. In the present invention, it is preferred to use a prepolymerized catalyst. In the prepolymerization, in addition to the catalyst component [A] and the organoaluminum compound [B], the electron donor catalyst component can also be present. In this case, an electron donor catalyst component is used in an amount of 0.01 to 30 mol, preferably 0.1 to 10 mol, more preferably 0.5 to 5 mol, per 1 gram atom of titanium in the titanium catalyst component [A]. You can also. In addition, prepolymerization can be carried out in an inert hydrocarbon solvent, using a liquid monomer as a solvent, or with a carbon number of 2 to 10 without using a solvent.
The α-olefin is prepolymerized, but prepolymerization in an inert hydrocarbon solvent is more preferred. [0051] The amount of polymerization in the prepolymerization is 0.00% per 1 g of titanium catalyst component.
The amount is 5 to 5000 g, preferably 1 to 1000 g, and more preferably 3 to 200 g. Inert hydrocarbon solvents used for prepolymerization include propane, butane, n-pentane, isopentane, n-
Aliphatic hydrocarbons such as hexane, isohexane, n-hebutane, n-octane, isooctane, n-decane, n-dodecane, kerosene; alicyclic hydrocarbons such as cyclopentane, methylcyclopentane, cyclohexane, methylcyclohexane; Examples include aromatic hydrocarbons such as benzene, toluene, and xylene, and halogenated hydrocarbons such as methylene chloride, ethyl chloride, ethylene chloride, and chlorobenzene. 3 to 10 aliphatic hydrocarbons are preferred. [0052] When an inert solvent or a liquid monomer is used in the prepolymerization, the titanium catalyst component [A] should be 0.001 to 500 mmol, particularly 0.005 to 200 mmol, in terms of titanium atoms, per 11 of the solvent. Preferably, the organoaluminum compound [B] has an A1/Ti (atomic ratio) of 0.
．． It is preferable to use it in a ratio of 5 to 500, preferably 1.0 to 50, more preferably 2.0 to 20. [0053] As the α-olefin used for prepolymerization, ethylene, propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-heptene, 1-octene, Those having 10 or less carbon atoms such as 1-decene are preferred, and ethylene is particularly preferred. These α-olefins may be homopolymerized, or two or more types may be copolymerized as long as a crystalline polymer is produced. [0054] The polymerization temperature in prepolymerization varies depending on the type of α-olefin and inert hydrocarbon solvent used and cannot be unconditionally defined, but is generally -40 to 80°C, preferably -20 to 40°C, more preferably is about -10 to 30°C. [0055] Hydrogen can be present in the prepolymerization. In the present invention, copolymerization of pentene-1 with ethylene is preferably carried out using the prepolymerized catalyst. α
- The titanium catalyst component [A] of the catalyst prepolymerized with olefin is 0.0 in terms of Ti atoms per 11 polymerization solvents.
001 to about 1 mmol, preferably about 0.001 to about 0.001 mmol.
Preferably, it is used in a proportion of 1 mmol. In addition, the titanium catalyst component [A] is 1.000 to 100.0 per gram.
00 g, preferably 2.000 to 50.000 g, more preferably 3.000 to 30.000 g of ethylene/pentene-1 copolymer is produced by copolymerization. [0056] 1 to 1000 mol, preferably 3 to 500 mol, particularly preferably 5 to 1 mol of the organoaluminum compound catalyst [B] per gram atom of titanium in the titanium catalyst component [A].
The use of 00 mol is preferred. Further, other compounds such as electron donor catalyst components may be added, and in that case, the metal element 1 in the organoaluminum compound catalyst component [B]
100 mol or less, preferably 1 mol or less per gram atom,
Particularly preferably, it is used in an amount of 0.001 to 0.1 mol. [0057] Polymerization temperature is 20 to 130°C, preferably 50 to 120°C
, more preferably at 70 to 110°C. Polymerization pressure is 1
〜50kg/cm2 Preferably 2~30kg/cm
2, more preferably 5 to 20 kg/cm2. Furthermore, an inert gas that forms a gaseous state within the polymerization system, such as methane, ethane, propane, butane, or nitrogen, may be supplied as appropriate. [0058] In the method for producing a copolymer according to the present invention, ethylene and pentene-1 are suspended in the presence of an olefin polymerization catalyst containing at least a solid catalyst component as described above, for example. This copolymerization reaction is carried out in a steady state in the presence of a liquid medium of the same weight or more as the copolymer obtained, and in a state in which not less than 30% by weight of the copolymer is eluted into the liquid medium. . [0059] The liquid medium present in an amount equal to or greater than the weight of the ethylene/pentene-1 copolymer obtained in a steady state refers to a liquid medium in which the above-mentioned solid substance such as a solid supported catalyst or a solid catalyst component is dispersed. A solvent used as a dispersion medium or a polymerization reaction solvent, such as propane, 1so-butane, n-butane, 1so-pentane, n
-Pentane, 1so-hexane, n-hexane, 1so
- Aliphatic hydrocarbons and their halogen derivatives such as hebutane, n-hebutane, 1so-octane, n-octane, 1so-decane, n-decane, dodecane, kerosene; cyclopentane, cyclohexane, methylcyclopentane, methylcyclohexane Aromatic hydrocarbons such as benzene, toluene, xylene, and halogen derivatives such as chlorobenzene can be mentioned. [0060] The production method according to the present invention is carried out in the presence of a catalyst and a liquid medium as described above, and in a steady state, the amount of ethylene/pentene-1 copolymer obtained is 30% by weight or more, preferably 0 to 10% by weight. % is carried out without dissolving into the liquid medium mentioned above. [0061] 30% by weight of the resulting ethylene/pentene-1 copolymer
If the copolymerization reaction is carried out in a state where the above components are eluted, it becomes difficult to continue the polymerization reaction. Hereinafter, the ethylene/pentene-1 copolymer obtained by the production method of the present invention will be specifically explained. [0062] The ethylene/pentene-1 copolymer obtained by the present invention is a random copolymer obtained by copolymerizing ethylene and pentene-1 in the presence of the above-mentioned olefin polymerization catalyst. In addition to ethylene and pentene-1 as described above, a small amount of other α-olefin or polyene may be copolymerized with this ethylene/pentene-1 copolymer. Examples of other α-olefins include propylene, 2-methylpropylene, 1-butene, 1-hexene, 4-methyl-1-pentene, 3-
Examples include methyl-1-pentene, 1-octene, nonene-1, decene-1, undecene-1, dodecene-1, and the like. In addition, the above-mentioned polyenes include butadiene, isoprene 1,4-hexadiene, dicyclopentadiene,
Examples include 5-ethylidene-2-norbornene. [0063] This ethylene-pentene-1 copolymer has an ASTM D
Melt flow rate measured by 1238E (M
FR) is 0.01 to 100 g/10 min, preferably 0
．． 05-50 g/10 minutes. This MFR is 0.
If the MFR is less than 1 g/10 min, the moldability of the copolymer will decrease and the transparency of the obtained film will tend to decrease, and if the MFR exceeds 100 g/10 min, the mechanical strength will decrease. cause a tendency to [0064] The ethylene/pentene-1 copolymer according to the present invention has a density of 0.90 to 0.96 g/cm3, preferably 0.91 to
0.95g/Cm3, particularly preferably 0.92-0.9
There is 4g/Cm3. Note that the density here is ASTM D
1505. [0065] In the ethylene/pentene-1 copolymer according to the present invention, the structural unit derived from pentene-1 accounts for 2 to 15% by weight, preferably 3 to 12% by weight, particularly preferably 4 to 10% by weight. The constituent units derived from ethylene are present in an amount of 85
It is present in an amount of -98% by weight, preferably 88-97% by weight, particularly preferably 90-96% by weight. [0066] As mentioned above, in this ethylene/pentene-1 copolymer, the content of structural units derived from α-olefins other than ethylene and pentene-1 is 5% by weight or less, preferably 3% by weight or less, particularly preferably may be included in an amount of up to 2% by weight. [0067] In addition, a sheet with a thickness of 0.5 mm obtained by heating the ethylene/pentene-1 copolymer obtained by the present invention to 200°C and melting it, then gradually cooling it to 50°C and crystallizing it (hereinafter referred to as DSC melting obtained when the sample obtained in this way is called "ultra-slow-cooled sample" and the temperature is raised from 10 °C to 200 °C at a temperature increase rate of 10 °C/min using DSC. The peak pattern has two melting peaks, and the ratio Hh/H1 of the high temperature side peak height Hh to the low temperature side peak height H1 and the density d of the copolymer satisfy the following formula. 60d-52,0<Hh/H1<80d-69,0
... [I] Preferably 60d -52,0<Hh/H1<80d -69,
1...[I'] Particularly preferably 60d-51,9<Hh/H1<80d-69,2
... [I”] (where Hh is the peak height on the high temperature side, H
l represents the peak height on the low temperature side, and d represents the density of the copolymer. ) Here, the analysis of the DSC melting peak pattern of the ultra-slow-cooled sample is based on
A tangent line was drawn starting from a point on the melting curve at 0° C., and this was used as the baseline. A perpendicular line was drawn from the highest point of the peak to this baseline, and the distance between this intersection and the highest point of the peak was determined as the peak height. [0068] The ratio (R5) of the film impact strength of a 40 μm thick film obtained by molding an ethylene/pentene-1 copolymer having the above properties into a cast film and the tear strength in the take-off direction of the film is: satisfies the following formula [II],
R5≧-201ogMFR-1000d +968
... [II] (In the formula, MFR represents the melt flow rate of the copolymer, and d represents the density of the copolymer.) Preferably, R3≧−201ogMFR−1000d +973
-[II'] More preferably, 200≧R3≧-201ogMFR-1000d +9
75 −・[II”] is satisfied. [0069] The ratio (R3) of this impact strength to tear strength is (-201
If it is less than ogMFR-1000d +968), the film tends to have high impact strength but poor unsealability, or the film tends to have good unsealability but poor impact strength. Note that the 40 μm thick film used to measure the R5 value is made of ethylene/pentene-1 copolymer at a resin temperature of 220 to 240°C, a chill roll temperature of 30 to 40°C, a film forming rate of 20 to 40 m/min, and a draft ratio ( Film thickness/Lip opening) 65m under conditions of 0.05 to 0.07
This film was produced using a T-die film molding machine equipped with an mφ extruder. [0070] Furthermore, the impact strength of a 40 μm thick cast film obtained by processing the ethylene/pentene-1 copolymer obtained according to the present invention is usually 1000 k100 O/Cm or more, preferably 1200 kg-cm/cm or more. [00713 In addition, the tear strength (T, ) of the film in the pulling direction,
Melt flow rate of ethylene/pentene-1 copolymer)
(MFR) preferably satisfies the relationship represented by the following formula [III]. 1ogT <, -〇, 371ogMFR-5, 1d+
6.72 −·−[III]D − (In the formula, d represents the density of the copolymer.) A more preferable relationship is 1ogT <, −0,371ogMFR−5,1d+
6.65...-[III']D - A particularly preferable relationship is 1ogT <, -0,371ogMFR-5,1d+
6.59 -[III"]D-. [0072] As described above, the tear strength (TM, ) in the pulling direction of the film and the MFR as shown in the above formula [III] A film with excellent impact strength and unsealability can be obtained from an ethylene/pentene-1 copolymer that satisfies the above relationship.
2 obtained by molding in accordance with ASTM D 1928
Stress cracking resistance of mm-thick press sheet (
SC resistance (ESCR'), measured according to ASTM D 1692, 100% Antalox, 50°C) is 10
hr or more and preferably satisfies the relationship shown by the following formula [IV-a], and ESCR≧0.7X10
(1og80-1ogMFR) (0,952-d)
-[IV-a] (in the formula, 2.0≦MFR≦50, and d represents the density of the copolymer), more preferably ESCR≧0.9X104 (log80-1ogMFR
)3(0,952-d)-[IV'-a] Particularly preferably, ESCR≧1. lX10 (1og80-1ogMFR
) (0,952-d) - [IV"-a] is satisfied. [0074] Also, a 2 mm product obtained by molding the ethylene/pentene-1 copolymer obtained according to the present invention in accordance with ASTM D 1928. Stress cracking resistance (SC resistance (ESCR), ASTM D 169 with a thickness of 0)
ESCR≧1.4xlO
(log40-1ogMFR) (0,952-d)
=-[IV-b] (in the formula, 1.0≦MFR≦20, and d represents the density of the copolymer) More preferably, ESCR≧1.7X10 (1og40-1ogMFR
) (0,952-d) -[IV'-b] Particularly preferably, ESCR≧2.0X10 (log40-1ogMFR
) (0,952-d) - [IV''-b] is satisfied. [0075] Furthermore, the ethylene-pentene-1 copolymer obtained by the present invention is molded in accordance with ASTM D 1928 to obtain a 2 mm product. Stress cracking resistance (SC resistance (ESCR') of press sheet of thickness, ASTM D 1
Measured according to 692, Antalox 10%, 60℃
) is 50 hr or more and preferably satisfies the relationship shown by the following formula [IV-c], ESCR≧0.50X10 (logloo −1log
MFR) (0,952-d) ...[IV-c]
(In the formula, 0.1≦MFR≦5, and d represents the density of the copolymer.) More preferably, ESCR≧0.65xlO (1oglOO−1ogMF
R)(0,952-d)-[IV'-c] Particularly preferably, ESCR≧0.80X10 (1og100-1ogM
FR) (0,952-d) = - [IV”-c] is satisfied. [0076] Further, the haze () (AZE
) and melt flow sheet of ethylene/pentene-1 copolymer) (MFR) preferably satisfy the relationship represented by the following formula [V]. 1ogHAZE≦15d -0,451ogMFR-1
2,23...[V] (in the formula, d represents the density of the copolymer) A more preferable relationship is l ogHAZE≦15d -0,451ogMFR-
12,26...[V'], and a particularly preferable relationship is 1ogHAZE≦15d -0,451ogMFR-1
2,30-[V"]. [0077] 0,1m used to measure the above physical properties
The press sheet having a thickness of m was made from an ethylene/pentene-1 copolymer in accordance with ASTM D 1928. Further, the HAZE value was measured in accordance with ASTM D 1003. [0078] The ethylene/pentene-1 copolymer having the above properties has excellent transparency, impact resistance, tear resistance, blocking resistance, low temperature heat sealability, heat resistance and stress crack resistance. , and has these excellent properties in a well-balanced manner, making it particularly suitable as a packaging film, but it is not limited to use as a film; ,
It can be processed into various molded products such as containers, daily necessities, pipes, and tubes by extrusion molding. It can also be made into various composite films by extrusion coating or coextrusion molding on other films, and can also be used for applications such as steel pipe coating materials, electric wire coating materials, and foam molded products. Alternatively, other thermoplastic resins such as high-density polyethylene, medium-density polyethylene, low-density polyethylene, polypropylene, poly-1-butene, poly-4-methyl-1-
Pentene, low-crystalline or amorphous copolymer of ethylene and propylene or 1-butene, propylene-1
- It can also be used in blends with polyolefins such as butene copolymers. [0079] Furthermore, ethylene pentene obtained as described above
If necessary, a heat stabilizer, a weather stabilizer, an antistatic agent, an antiblocking agent, a lubricant, a nucleating agent, a pigment, a dye, an inorganic or organic filler, etc. can be added to the copolymer 1. [0080] (Effect of the invention) In the method for producing an ethylene/pentene-1 copolymer according to the present invention, the polymerization reaction is carried out under the specific conditions described above, so that the resulting copolymer When formed into a film, it has an excellent balance between impact resistance and ease of opening.It also has good SC resistance and haze, so it is suitable for application to various uses.The following is a concrete example of the present invention. The present invention is not limited to these examples. [0081]

[Example 1] 119 g of commercially available anhydrous magnesium chloride, 579 ml of 2-ethylhexyl alcohol and 5.61 ml of decane were mixed into 14
A heating reaction was carried out at 0° C. for 3 hours to obtain a homogeneous solution containing magnesium chloride. [0082] 70 ml of propionic acid was further added to this solution, and 70 ml of propionic acid was added.
After heating the reaction at ℃ for 1 hour, it was cooled. This solution was heated to 178 m of triethylaluminum at 20°C with stirring.
A mixed solution consisting of 1.11 and 1.11 of triethylaluminum and decane was added dropwise over 30 minutes, then the temperature was raised to 80°C over 1 hour, and a heating reaction was carried out at 80°C for 1 hour. 3 of the solution
The mixture was added dropwise for 0 minutes, and the reaction was then carried out at the same temperature for 30 minutes. Then, 189ml of diethylaluminum chloride
A mixed solution consisting of 1.31 parts of decane and 1.3 parts of decane was added dropwise over 30 minutes, and the reaction was carried out again at 80°C for 1 hour. [0083] Next, a solid portion was separated by filtration to synthesize a solid component. After resuspending the solid component thus obtained in decane 51, 2-ethylhexoxytitanium trichloride was added to
After adding 88 mmol and carrying out a reaction at 80° C. for 1 hour, the mixture was washed with decane to prepare a solid titanium catalyst component. On the other hand, take a portion of the slurry, remove decane, and -
After replacing the catalyst with hexane, it was dried (1), and the catalyst composition was investigated using this dried catalyst. The composition of the solid titanium catalyst component was 13% by weight titanium, 12% by weight magnesium, and 36% by weight chlorine. [Prepolymerization] Hexane 10 was added to a 2001 reactor equipped with a stirrer in a nitrogen atmosphere.
After adding 1.5 mol of triethylaluminum and 0.5 mol of the titanium catalyst component in terms of titanium atoms, ethylene gas was fed into the mixed solution at a rate of 5 kg/hour for 4 hours. During this time, the temperature was maintained at 30°C. Four hours after starting the ethylene feed, the ethylene feed was stopped and nitrogen was fed instead to replace the inside of the reactor with nitrogen. After stopping the stirring and allowing the mixture to stand still, the supernatant liquid was removed, purified hexane was added, and the mixture was washed three times. [Polymerization] Using a mixture of the prepolymerized titanium catalyst component and triethylaluminum/diethylaluminium chloride (1/1 molar ratio) as a catalyst, ethylene and 1% were mixed in hexane suspension.
- Copolymerization of pentene was carried out continuously using a 2501 polymerizer. The details of the polymerization conditions and the polymerization results are shown in Table 1, and the physical property evaluation results are shown in Table 2. [0084]

[Table 1] [0085]

[Table 2]

Claims (1)

[Claims] 1. A method for producing an ethylene/pentene-1 copolymer by copolymerizing ethylene and pentene-1 in suspension in the presence of a catalyst containing a solid catalyst component, the method comprising: The copolymer is produced in a state where 30% by weight or more of the polymer is not eluted into the liquid medium and at a polymerization temperature range of 0 to 120°C, and the resulting copolymer is produced as follows (A
) to (C) A method for producing an ethylene/pentene-1 copolymer characterized by satisfying the requirements; (A) Density measured by ASTM D 1505E is 0.90 to 0.96 g/cm^3 (B) The structural unit derived from pentene-1 is 2 to 15% by weight, and (C) The impact strength of a 40 μm thick film obtained by molding the copolymer into a cast film and the tensile strength of the film. The ratio (RS) to the tear strength in the tearing direction satisfies the following formula. RS≧-20logMFR-1000d+968 (where MFR represents the melt flow rate of the copolymer, d
represents the density of the copolymer. )