JPH01126311A - Production of ethylenic copolymer - Google Patents

Abstract

PURPOSE:To obtain a copolymer having excellent melt fluidity in copolymerizing ethylene with an unsaturated carboxylic acid (ester) by using a catalyst consisting of a transition metal compound and an organometallic compound, by using a specific transition metal compound and a specific organometallic compound. CONSTITUTION:Ethylene is copolymerized with an unsaturated carboxylic acid (ester) [e.g. acrylic acid (methyl ester)] by using a catalyst consisting essentially of a transition metal compound (preferably chromium compound) comprising one or more of chromium compound, vanadium compound, titanium compound and hafnium compound and an organometallic compound (preferably aluminum compound) of group I-V of the periodic table in the presence of Lewis acid and an inner olefin (e.g. 2-butene) to give a copolymer to readily regulate molecular weight. The catalyst has the molar ratio of the organometallic atom. of the organometallic compound to the transition metal atom. of the transition metal compound of preferably 1-1,000.

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention is useful for obtaining ethylene copolymers from ethylene and unsaturated carboxylic acids or their esters using chromium catalysts, etc., which allows easy control of molecular weight and has low melt-melt droplet mobility. This invention relates to a manufacturing method that yields a good copolymer. [Prior art and problems to be solved by the invention] ゛Conventionally, polyethylene has been resistant to water and chemicals. It has excellent electrical properties and is used in a wide range of applications. However, because it is chemically inert, it has the disadvantage of poor adhesion, printability, and dyeability, which limits its use in applications that require these properties. Therefore, in order to improve these properties of polyethylene, a method has been proposed in which ethylene and a compound copolymerizable with ethylene are copolymerized. For example, Tokuko Sho 49-2331
No. 7 discloses a method of copolymerizing ethylene and acrylic ester using a polymerization catalyst in the presence of a Lewis acid compound. However, as the molecular weight of the ethylene copolymer increases, its melt fluidity becomes poorer, and therefore its processability generally deteriorates. Up to now, methods for adjusting the molecular weight have been carried out, such as adding hydrogen gas, adjusting the degree of polymerization reaction, and adding organic metals. Among these methods, in the method of adding hydrogen gas, increasing the partial pressure of hydrogen lowers the activity, and increasing the partial pressure of ethylene makes it difficult to effectively reduce the molecular weight. Furthermore, in the method of adjusting the polymerization temperature, the molecular weight can be lowered by raising the temperature, but the catalyst is significantly deactivated, which is undesirable. Further, in the method of controlling by adding an organic metal, the copolymerizability changes and there is a problem that it is difficult to control the copolymer composition. The inventors of the present invention have conducted extensive research in order to develop a method to solve the above-mentioned conventional problems. As a result, by using a specific catalyst and performing a copolymerization reaction of ethylene and an unsaturated carboxylic acid or its ester in the presence of an internal olefin, the molecular weight can be easily controlled and a copolymer with good fluidity can be obtained. Based on this finding, we have completed the present invention. [Means for Solving the Problems] That is, the present invention uses a catalyst containing [A] a transition metal compound and [B] an organometallic compound as main components, and reacts ethylene with an unsaturated carboxylic acid or an unsaturated carboxylic acid in the presence of a Lewis acid. In the method for producing an ethylene copolymer by copolymerizing a saturated carboxylic acid ester, [A] one or more compounds selected from a chromium compound, a vanadium compound, a titanium compound, a zirconium compound, and a hafnium compound are used as the transition metal compound. , [B] Organometallic compounds listed in Periodic Table 1~
The present invention provides a method for producing an ethylene copolymer, which is characterized by using a group V organometallic compound and carrying out a copolymerization reaction in the presence of an internal olefin. First, in the method of the present invention, as the transition metal compound [A] of the catalyst, a compound of 1 f1 or more selected from chromium compounds, vanadium compounds, titanium compounds, zirconium compounds, and hafnium compounds is used. The chromium compound is chromium carboxylate. At least one selected from the group consisting of chromium alkoxy compounds, chromium chelate compounds, chromium π-complexes, chromaryl compounds, and chromium halides is used. Specifically, the chromium carboxylate is Cr(C
)IsCOO)3. Cr[CJoCH(hHs)Co
o]3. Aliphatic carboxylates such as Cr(C6HsCOO)s, Cr((:aHsCOO)31Cr(
CH3・C6HsCOO)s, Cr(C6HsCOO
) Aromatic carboxylic acid salts such as s, and carboxylic anhydride adducts, ester adducts, ether adducts, and ketone adducts of the above carboxylic acid salts. Next, specific examples of chromium alkoxy compounds include tetramethoxychromium, tetraethoxychromium, tetra-n
-butoxychromium, tetra-1-butoxychromium, tetra-t-butoxychromium. Tetrahexyloxychrome, tetrastearyloxychrome, tetraphenoxychrome, triethoxychrome monochloride, jetoxychrome dichloride, tri-n
-butoxychrome monochloride, tri-t-butoxychrome monochloride, and the like. Further, the chromium chelate compound specifically has the formula Cr
Chromium tris acetylacetonate represented by (acac)3, chromium tris(2-methyl-1,3-butanedioate) represented by Cr(mbd)3. Chromtris (1,3
-butanedioate), chromium tris (trifluoroacetylacetonate), chromium tris (hexafluoroacetylacetonate), and the like. Here (a
cac) represents an acetylacetonate group, and chromium trisacetylacetonate is represented by the structural formula. In addition, (mbd) represents a 2-methyl-1,3-butanedioate group, and chromium tris (2-methyl-1,3-butanedioate) is represented by the following structural formula. Furthermore (bd
) represents a 1,3-butanedioate group, and chromium tris(l,3-butanedioate) is represented by the following structural formula. Further, chromium tris (trifluoroacetylacetonate) is represented by the following structural formula, and chromium tris (hexafluoroacetylacetonate) is represented by the following structural formula. As a chromium π-complex, (cp) zcr ((c
p) represents a cyclopentadienyl group), (CaHa) z
Bisbenzenechromium + (2CaH
s) (CaHa) Diphenylbenzene chromium represented by Cr, dihexamethylbenzene chromium represented by the formula 5 π-cyclopentadienyl bromochromium acetylacetate represented by the formula H3 / \ H3 π-cyclopenta represented by the formula 2 Aromatic ring π-complexes such as π-cyclopentadienyl-π-cycloheptadienylchromium expressed by the formula 1, tris(η-allyl)chromium, tetrakis(η-allyl)chromium, etc. Examples include π-allyl complex. Furthermore, examples of the chromaryl compound include diphenylchromium, triphenyltris(tetrahydrofuran)chromium, and the like. Next, the preferable chromium halide is a formula CrX'n (wherein x1 represents a halogen atom, n
indicates 2 or 3. ). Specifically, chromium trichloride, chromium tribromide, chromium triiodide, chromium dichloride, chromium tribromide1. Examples include chromium diiodide. Further, specific examples of vanadium compounds include VC1'4.
Vanadium chloride such as VCj2, VOCj3. V.O.
Vanadium oxychloride such as Cj'2, ■(0・n-C
4) 1s) a. VO (OC28s) 3, VO (0・n-CJo)
Vanadium alkoxides such as 3, cyclopentadienyl vanadium derivatives such as dicyclopentadienyl vanadium chloride, V(acac)6, VO(a
Vanadium acetylacetonate compounds such as cac) 2 can be mentioned. Next, as a titanium compound, specifically TtC1'4゜T
iBr4. titanium tetrahalides such as TiI4,
Ti(OCHs)(:I!s, Ti(OCJs)Cj
s, Ti(0·n-C4He)C1's. Trihalogenated monoalkoxytitanium such as Ti(OC,H,)Br=, Ti(OCH5), Cj,, T
i(OC,)1. )20J! ,. Ti(0・n-C4)1. )2C1)2. Ti(OC)
2H5) dihalogenated dialkoxytitanium such as 2Or2, Ti(OCL) in 3C. Ti(OC2H5)311:il, Ti(0・n-C
4H3) 3Cj! , Ti(QC2H,), monohalogenated trialkoxytitanium such as Br, and even Ti
(OCHs) a, Ti (Oll:Js) a
, Ti (OC4H,I)4゜Ti (0・n-C4
Tetraalkoxytitanium such as Hi+)4 and dicyclopentadienyltitanium dichloride. Mention may be made of cyclopentagenyl titanium derivatives such as dimethyldicyclopentagenyl titanium. In addition, as specific examples of zirconium compounds, as well as the above titanium compounds, zirconium tetrahalide,
Examples include trihalogenated monoalkoxyzirconium, dihalogenated dialkoxyzirconium, monohalogenated trialkoxyzirconium, and tetraalkoxyzirconium. Genyl zirconium derivatives can be mentioned as suitable ones. Furthermore, specific examples of hafnium compounds include tetrahalogenated hafnium, trihalogenated monoalkoxyhafnium, dihalogenated dialkoxyhafnium, monohalogenated trialkoxyhafnium, tetraalkoxyhafnium, dicyclopentadienylhafnium chloride, dimethyldicyclo Cyclopenta such as pentagenyl hafnium? Enilhafnium conductor can be mentioned. [A] The transition metal compound used in the present invention is selected from the above-mentioned chromium compounds, vanadium compounds, titanium compounds, zirconium compounds, or hafnium compounds. or more compounds may be used,
Particularly suitable are chromium compounds. Next, as the other main component [B] of the organometallic compound of the catalyst, an organometallic compound of Groups I to V of the periodic table is used. Specifically, the metals used here are lithium, magnesium, zinc,
cadmium, aluminum. Boron, gallium, silicon, tin, antimony. Examples include bismuth. Among these, preferred compounds include aluminum, tin, magnesium, gallium,
Examples include metal compounds of zinc. Among these, there are various examples of compounds when the metal is aluminum, specifically trimethylaluminum and triethylaluminum. Trialkylaluminium compounds such as triisopropylaluminum, triisobutylaluminum, trioctylaluminum, and diethylaluminum monochloride, diethylaluminum monopromide, diethylaluminium monoiodide, diisopropylaluminum monochloride, diisobutylaluminium, miniram monochloride. Dialkyl aluminum monohalides such as dioctyl aluminum monochloride or alkyl aluminum sesquihalides such as methyl aluminum sesquichloride, ethyl aluminum sesquichloride, ethyl aluminum sesquipromide, and butyl aluminum sesquichloride are suitable; Alkyl group-containing aluminoxanes produced by can also be used. Furthermore, other organometallic compounds include alkyllithiums such as methyllithium, ethyllithium, propyllithium, butyllithium, alkylmagnesiums such as diethylmagnesium, ethylbutylmagnesium, di-n-butylmagnesium, and ethylchloromagnesium, dimethylzinc, Dialkyl zinc such as diethyl zinc, dipropyl zinc, dibutyl zinc, trimethyl gallium, triethyl gallium, tripropyl gallium,
Examples include alkyl gallium compounds such as tributyl gallium, alkyl boron compounds such as triethyl boron, tripropyl boron, and tributyl boron, and alkyl tin compounds such as tetraethyl tin, tetrapropyl tin, tributylchlorotin, tetraphenyltin, and triphenylchlorotin. . Further, if necessary, a catalyst activator can be used together with the acid component [B]. The activators include magnesium and manganese carboxylates, organic phosphates, and organic surface phosphates. Included are alkoxides and halides. Here, to specifically show magnesium and manganese salts, carboxylates have the general formula M (R'C00)
, or M (R'C00)X' [wherein M represents magnesium or manganese, and R' has 1 to 20 carbon atoms
an alkyl group, an aryl group, or an aralkyl group.In the above general formula representing magnesium carboxylate or manganese carboxylate, R1 is as described above, but is preferably an aliphatic alkyl group having 6 or more carbon atoms, particularly preferably 8 carbon atoms. The above aliphatic alkyl group, specifically a hexyl group. Examples include heptyl group, octyl group, 2-ethylhexyl group, nonyl group, decyl group, lauryl group, myristyl group, heptadecyl group, and stearyl group. Further, unsaturated alkyl groups such as an oleyl group can be mentioned. Next, there are various organic phosphates and organic phosphites of magnesium and manganese, and there are no particular restrictions, but it is preferable to react an organic magnesium compound or an organic manganese compound with a hydrogen-containing phosphorus compound. This can be obtained by Here, the organomagnesium compound or organomanganese compound has the formula R"R'M [
In the formula, R2 and R3 each represent an alkyl group or an aryl group having 1 to 10 carbon atoms, and M represents magnesium or manganese. ] or R'MX'
[In the formula, R2 represents an alkyl group or an aryl group having 1 to 10 carbon atoms, M is magnesium or manganese,
3 represents a halogen atom. ] Compounds represented by these formulas can be cited as preferred. Specific examples include ethylbutylmagnesium, dibutylmagnesium, diethylmagnesium, dihexylmagnesium, dimethylmanganese, diphenylmanganese, ethylmagnesium chloride, ethylmagnesium iodide, and methylmanganese iodide. Moreover, complex salts of these organic aluminum and organic zinc can also be used. On the other hand, hydrogen-containing phosphorus compounds include alkyl or arylphosphines such as methylphosphine, ethylphosphine, propylphosphine, butylphosphine, and phenylphosphine, and dialkyl or diarylphosphines such as diethylphosphine, dipropylphosphine, dibutylphosphine, and diphenylphosphine. , alkyl or aryl phosphonic acids such as ethyl phosphonic acid, propyl phosphonic acid, dialkyl or diarylphosphinic acids such as diethyl phosphinic acid, dipropylphosphinic acid, dibutyl phosphinic acid, didodecyl phosphinic acid, diphenyl phosphinic acid, phosphorous acid methyl ester , phosphite butyl ester, phosphite dimethyl ester, phosphite dipropyl ester, phosphite dibutyl ester, phosphite dodecyl ester, phosphite dilauryl ester, phosphite dioleyl ester, diphenyl phosphite Examples include phosphorous esters such as esters, phosphoric acid esters such as ethyl phosphate, propyl phosphate, dipropyl phosphate, dibutyl phosphate, dioctyl phosphate, and didodecyl phosphate. Examples of magnesium or manganese alkoxides include magnesium dialkoxides such as magnesium dimethoxide, magnesium jetoxide, magnesium diproboxide, magnesium dibutoxide, magnesium diheptoxide, magnesium dioctoxide, and magnesium dialkoxide, or manganese dibutoxide; Examples include manganese dialkoxides such as manganese dioctoxide and manganese diasuaroxide. Among these, those containing long-chain alkyl groups are preferred because they form microgels or are soluble in hydrocarbon solvents such as hexane, heptane, toluene, etc., and have high activity. Particularly preferred are those having a hydrocarbon group having 6 to 20 carbon atoms. Further, various kinds of halides can be used, but it is preferable that the metal halide has a smaller electronegativity of metal ions than that of chromium-11 valent ions. Specifically, for example, MgCjz, MgBr
,, Mgr,, MnCj,, MnBr,, Mn
12, etc. As a catalyst activator, any one of the above-mentioned 1f! Alternatively, 2211 or more are used in combination. As mentioned above, in the present invention, a transition metal compound [A] and an organometallic compound [B] are used as a catalyst, with an activator added as needed. The catalyst is usually prepared by adding the above [^J acid component [B] acid component and activator to a suitable solvent such as hexane, toluene, decalin, etc. and mixing at a temperature of -80 to 200°C, preferably -20 to 1004°C. All you need to do is stir for 20-300 minutes.
[^] Acid component [8] The ratio of the component used is not particularly limited, but usually 0.1 to 5ooo (molar ratio) of organometallic atoms of [81 to transition metal atoms of [A], preferably 1
The ratio may be ~1000 (molar ratio), and the activator may be

It is preferable to add 0.1 to 10 (molar ratio) to the total amount of [^] and [B]. In the method of the present invention, an ethylene copolymer is produced by copolymerizing ethylene and an unsaturated carboxylic acid or an unsaturated carboxylic acid ester in the presence of a Lewis acid using the above catalyst. This copolymerization reaction is carried out in the presence of an internal olefin. Here, internal olefin refers to an olefin that has a double bond inside its molecular formula, whereas α-olefin has a double bond at the end of its molecular formula, specifically 2-butene. , 2-pentene, 2-hexene, 3
-Linear alkanes such as hexene, 2-hebutane, 3-heptene, 2-octene, 3-octene, 4-octene, tetramethylethylene, trimethylethylene, 4-methylpentene-2,5-methylhexene- Branched alkenes such as 2, cyclobutene, cyclopentene, cyclohexene, cycloheptene, cyclooctene, methylcyclobutene, methylcyclopentene, methylcyclohexene, methylcycloheptene, dimethylcyclohexene,
Examples include alicyclic alkenes such as trimethylcyclopentene, trimethylcyclohexene, isopropylmethylcyclohexene, and norborneneindene. The amount of internal olefin added depends on the conditions of the copolymerization reaction,
In particular, the reaction temperature, which affects the molecular weight of the produced copolymer, is increased or decreased by taking into account the reaction pressure, the amount of catalyst charged, the amount of hydrogen used, and the amount of unsaturated carboxylic acid or its ester charged.
The range is 0.01 to 1000 mol%, preferably 0.1 to 1θ mol%, based on the amount of unsaturated carboxylic acid or its ester charged. If the amount added is too small, the effect of controlling the molecular weight will not be sufficient, while if it is too large, the copolymerization activity will be lowered, which is undesirable. By adding this internal olefin, the molecular weight can be controlled and the fluidity can be improved. Examples of the Lewis acid include Lewis acid compounds capable of forming a complex with a lone pair of electrons of a polar group, such as halogenated compounds of Groups I to V or Group II of the periodic table. Especially aluminum, boron, and zinc. Halogenated compounds such as tin, magnesium, antimony, such as aluminum chloride, aluminum bromide, ethylaluminum dichloride, ethylaluminum sesquichloride, diethylaluminum dichloride, triethylaluminum, trimethylaluminum, boron trichloride, zinc chloride. Tin tetrachloride, alkyltin halide, magnesium chloride, antimony pentachloride, antimony trichloride, etc. are preferred, and aluminum chloride, aluminum bromide, and ethylaluminum dichloride are particularly preferred. Next, the unsaturated carboxylic acid or its ester to be copolymerized with ethylene is not particularly limited, but a compound represented by the formula % is usually used. This - R4 in the formula
is a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 3 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aryl group having 7 to 20 carbon atoms. R11 represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 3 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aryl group having 7 to 20 carbon atoms. ~20 aralkyl group, p represents an integer of 0 to 20. Specific examples of the unsaturated carboxylic acid represented by the above general formula include acrylic acid, methacrylic acid, α-chloroacrylic acid, 3-butenoic acid, 4-pentenoic acid, 6-hebutenoic acid,
Examples include 8-nonenoic acid and 10-undecenoic acid, and these can be used alone or in combination of two or more. Specific examples of the unsaturated carboxylic acid ester represented by the above general formula include methyl acrylate, ethyl acrylate,
Propyl acrylate, butyl acrylate, acrylic acid n
- Acrylic acid esters such as octyl, 2-ethylhexyl acrylate, benzyl acrylate; methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, phenyl methacrylate. α-Substituted acrylic esters such as methyl α-chloroacrylate, ethyl α-chloroacrylate; methyl 3-butenoate, ethyl 3-butenoate, methyl 4-pentenoate,
Ethyl 6-heptenoate, methyl 8-nonenoate, methyl 10-undecenoate, propyl 10-undecenoate, 10
-butyl undecenoate, hexyl 10-undecenoate,
Examples include carboxylic acid esters having a terminal double bond such as octyl 10-undecenoate, decyl 10-undecenoate, cyclohexyl 10-undecenoate, and phenyl 10-undecenoate, which may be used alone or in combination of two or more. Can be used in combination for diagnosis. The ratio of the above-mentioned unsaturated carboxylic acid or its ester to ethylene may be arbitrarily selected depending on the physical properties required of the intended copolymer. In addition, when copolymerizing ethylene and unsaturated carboxylic acid or its ester, a small amount of α-olefin having 3 or more carbon atoms may be copolymerized.
Examples of the olefin include propylene, 1-butene, 1-pentene, 81-hexene, 1-octene, 3-methylbutene-1,4-methylpentene-1,1-decene, and the like. The blending amount of this α-olefin is 0.01 to 100 mol%, preferably 0.05 to 10 mol%, based on the amount of ethylene charged. The ratio of the Lewis acid and unsaturated carboxylic acid or ester thereof used is 0.1 to 20 (mole ratio), preferably 0.2 to 5 molar, of the Lewis acid to 1 part of the unsaturated carboxylic acid or ester thereof. (molar ratio). There are no particular restrictions on the type of polymerization, and slurry polymerization is used. Either solution polymerization, gas phase polymerization, etc. are possible, and both continuous polymerization and discontinuous polymerization are possible. In this case, fatty acid hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, halogenated hydrocarbons, and halogenated carbons are used as the polymerization solvent. Specifically, pentane, hexane, heptane, octane, decane, dodecane, cyclohexane, benzene, toluene, xylene, ethylbenzene, chlorobenzene, ethylene dichloride, kerosene, etc. are used.As for polymerization conditions, the reaction pressure is normal pressure to 100 ml. kg
/cm'G. Preferably the pressure is from normal pressure to 30 kg/cm'G, and the reaction temperature is from -80 to 200°C, preferably from -50 to 80°C. Although the reaction time is arbitrary, it is usually 1 minute to 10 minutes.
Molecular weight adjustment during polymerization can be carried out very easily by adjusting the amount of internal olefin added, as mentioned above. [Examples] Next, the present invention will be explained by examples, but the present invention is not limited thereto unless it exceeds the scope of the present invention. Example 1 (1) Preparation of chromium catalyst component Into a 200 mN flask purged with argon,
Add 10 0mm stainless steel balls, then add 3.6g (4 mmol) of chromium stearate and 100ml of toluene.
The mixture was ball-milled for 10 hours with stirring at room temperature under nitrogen. Next, add toluene to this to bring the total amount to 20
It was set to 0 mj. As a result, a chromium catalyst-containing component in the form of a blackish-purple gel was obtained. (2) Manufacture of copolymer Dehydrated toluene 80ml in an 11-volume stainless steel autoclave
0 mj was injected, and then 26.7 mmol of a toluene solution of an equimolar mixture of ethyl acrylate and aluminum trichloride was added. Thereafter, while maintaining the temperature at 30°C, 40 mmol of diethylaluminum monochloride and 1.0 mmol (in terms of chromium) of the chromium-containing catalyst component prepared in (1) above were added, and the stirring speed was increased to 50 Orp.
Set to a+, 8 g of cis-2-butene was introduced, and then hydrogen gas was introduced at 2.0 kg/cm'G to saturate it.6 Then, 8.0 kg/cm'G of ethylene was introduced,
The total pressure was set to 10.0 kg/cm"G. After polymerization for 3 hours, the pressure was removed and the contents were poured into methanol to precipitate. The precipitated solid was collected by furnace and treated with a hydrochloric acid-methanol mixture. The amorphous polymer was removed by demineralization and acetone extraction for 5 hours.
When dried under reduced pressure at ℃ for 2 hours, the white polymer was 40.5
g was obtained. In the infrared absorption spectrum of the obtained white polymer (copolymer), absorption based on a carbonyl group at 1730 cm-' and absorption based on an ether bond at 1180 cm'' were observed. These peaks (mouth Jt[J) and 72
From the peak ratio of methylene chains observed near 0ca+-' and 730cm-', the content of acrylic ethyl units in the copolymer is 0.6 mol%, and the melt index (Ml) at 190°C is 2,18kg) is 0.
It took 14g and 710 minutes. Comparative Example 1 The same procedure as in Example 1 was conducted except that cls-2-butene, which is an internal olefin, was not added. The results are shown in Table 1. The obtained copolymer had no fluidity under the same conditions as in Example 1, and was a high molecular weight material whose melt index value could not be measured. Example 2 The same procedure as Example 1 was carried out except that ethylene was introduced at 10 kg/cm"G and hydrogen gas was not used. The results are shown in the first example.
Shown in the table. Comparative Example 2 The same procedure as in Example 1 was conducted except that cis-2-butene was not added as the internal olefin. The results are shown in Table 1. As in Comparative Example 1, Ml could not be measured. Example 3 (1) Preparation of chromium-containing catalyst component 2.1 g (6 mmol) of chromium triacetylacetonate was placed in a 200 mj flask purged with argon, and 200 mj of toluene was added thereto to dissolve it. The obtained solution was used as a chromium-containing catalyst component in the following reaction. (2) Production of copolymer A copolymer was produced in the same manner as in Example 1, except that the chromium-containing catalyst component prepared in (1) above was used and the temperature was 25°C. The results are shown in Table 1. Comparative Example 3 The same procedure as Example 3 was carried out except that the internal olefin cis-2-butene was not added. The results are shown in Table 1. As in Comparative Example 1, MI was not measurable. Example 4 (1) Preparation of chromium-containing catalyst component 6.6 g (13.7 mmol) of chromicum tris-2-ethylhexanoate was placed in a 2001 flask purged with argon, and 200 mR of toluene was added to dissolve it. . The resulting solution was used as a chromium-containing catalyst component. (2) Production of copolymer A copolymer was produced in the same manner as in Example 3, except that the chromium-containing catalyst component prepared in (1) above was used. The results are shown in Table 1. Comparative Example 4 The same procedure as Example 4 was carried out except that the internal olefin cts-2-butene was not added. The results are shown in Table 1. As in Comparative Example 1, MI was not measurable. Example 5 (1) Preparation of chromium-containing catalyst component A 1.
1 g (4.45 mmol) and 40 ml of acetic anhydride.
40 ml of acetic acid was added and reacted for 20 hours under stirring and rapid flow, and then acetic acid and acetic anhydride were distilled off under reduced pressure to obtain a green solid. Next, under an argon stream, it was dried at 120°C for 48 hours, the temperature was lowered, toluene was added, and the temperature was dried at 200°C.
1! A green catalyst slurry was obtained. (2) Production of copolymer Using the chromium-containing catalyst component obtained in (1) above, the same procedure as in Example 3 was carried out except that ethylene was introduced at 10 kg/c+a2G and hydrogen gas was not used. The results are shown in Table 1. Comparative Example 5 The same procedure as Example 5 was carried out except that the internal olefin cis-2-butene was not added. The results are shown in Table 1. As in Comparative Example 1, MI was not measurable. Example 6 8 kg/cab2G of ethylene, 2 kg of hydrogen gas
/cm2a and the temperature was 20°C.
I did the same thing. The results are shown in Table 1. Comparative Example 6 The same procedure as in Example 6 was conducted except that the internal olefin cis-2-butene was not added. The results are shown in Table 1. Example 7 The same procedure as in Example 1 was conducted except that the chromium-containing catalyst component used in Example 1 was used and 2-heptene was added instead of cis-2-butene as the internal olefin. The results are shown in Table 1. Example 8 The same procedure as in Example 1 was conducted except that the chromium-containing catalyst component used in Example 1 was used and 2-hexene was added instead of cis-2-butene as the internal olefin. The results are shown in Table 1. Example 9 The same procedure as in Example 1 was carried out except that the chromium-containing catalyst component used in Example 1 was used and cyclohexene was added instead of cis-2-butene as the internal olefin. The results are shown in Table 1. Example 1O (1) Preparation of vanadium-containing catalyst component Toluene was added to 2.35 mmol of vanadium oxytrichloride to make a 200 mj toluene solution, and this solution was used as a vanadium-containing catalyst component. (2) Production of copolymer Using 0.5 mmol of the vanadium-containing catalyst component obtained in (1) above, the amount of diethylaluminum monochloride used was 30 mmol, and equimolar amounts of ethyl acrylate and aluminum trichloride were used. Example 1 except that 53.4 mmol of the mixture was used and the temperature was 50°C.
I did it in the same way. The results are shown in Table 1. Comparative Example 7 The same procedure as in Example 10 was carried out except that the internal olefin cis-2-butene was not added. The results are shown in Table 1. [Effects of the Invention] According to the method of the present invention, the above-mentioned [A] transition metal compound,
[B] Efficiently adjusting the molecular weight by adding a small amount of internal olefin during the copolymerization reaction of ethylene and unsaturated carboxylic acid or its ester using a catalyst containing an organometallic compound as the main component. A copolymer with good flow properties can be obtained. Furthermore, the content of unsaturated carboxylic acid comonomer in the resulting copolymer can be increased.

Claims (1)

[Claims] Ethylene and unsaturated carboxylic acid or unsaturated carboxylic acid ester are copolymerized in the presence of a Lewis acid using a catalyst containing [A] a transition metal compound and [B] an organometallic compound as main components to produce an ethylene copolymer. In the method of manufacturing [A
] Using one or more compounds selected from chromium compounds, vanadium compounds, titanium compounds, zirconium compounds and hafnium compounds as transition metal compounds, [B]
1. A method for producing an ethylene copolymer, which comprises using an organometallic compound of Groups I to V of the periodic table as the organometallic compound, and carrying out a copolymerization reaction in the presence of an internal olefin.