JPH0441169B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing an ethylene copolymer by copolymerizing ethylene and α-olefin in the presence of a novel catalyst system comprising a vanadium compound and an organoaluminum compound. Conventionally, various catalysts for producing ethylene copolymers have been proposed, and so-called Ziegler-type catalysts are particularly effective. Among Ziegler type catalysts,
In particular, trivalent to pentavalent vanadium compounds soluble in the polymerization solvent (e.g. vanadium triacetylacetonate, vanadium tetrachloride oxyvanadium trichloride)
It is well known that a catalyst consisting of aluminum and an organoaluminum compound has extremely excellent effects.
Moreover, in the presence of these catalysts, ethylene and α-
Copolymerizing olefins (e.g. propylene, butene-1) to produce soft plastics (ethylene content 70-95% by weight), copolymerizing ethylene and α-olefins, or copolymerizing these with polyenes. It is also known to produce elastomers (ethylene content 20-70% by weight) (e.g.
44-9668, Japanese Patent Publication No. 46-11028, Japanese Patent Publication No. 47-26185). However, these catalysts have a narrow molecular weight distribution and a compositionally homogeneous copolymer can be obtained at a polymerization temperature of 20°C or lower; The problem is that the more a copolymer (ethylene content is 50% by weight or more) is produced, the wider the molecular weight distribution and composition distribution of the copolymer become, making it difficult to obtain a homogeneous copolymer. Therefore, for example, in solution polymerization of elastomers, high molecular weight and highly crystalline components become insoluble in the polymerization solvent and precipitate during polymerization, resulting in a heterogeneous polymer solution. It has the disadvantage that it tends to cause operational problems such as blockage of the liquid extraction line. In addition, for example, in slurry polymerization of soft plastics, low molecular weight and amorphous components dissolve in the polymerization solvent, resulting in blockage in the extraction line due to increased viscosity of the polymer liquid, or separation of the solvent from the slurry using a centrifuge, etc. However, this method has disadvantages in production, such as a decrease in the yield of the copolymer. Furthermore, since the composition of the copolymer is non-uniform, it also has drawbacks such as deterioration in quality such as strength and transparency. Although Japanese Patent Publication No. 89-18946 does not describe a specific method for synthesizing the catalyst, it also mentions that vanadium trichloride complexed with ethanol, which is insoluble in hydrocarbons, and dialkylaluminum monochloride can be used to synthesize hydrocarbons. Amorphous ethylene-α at polymerization temperatures from 0° to −50°C in the presence of a catalyst consisting of dissolved reaction products.
- A method for producing an olefin copolymer has been proposed and carried out using an aromatic hydrocarbon as a polymerization solvent that substantially dissolves the catalyst. Generally, when copolymerization is carried out in an aromatic hydrocarbon solvent, a low molecular weight ethylene copolymer is produced.
In addition, aromatic hydrocarbon solvents are more toxic than aliphatic hydrocarbons, and care must be taken in terms of operational operations such as polymerization and post-treatment, and quality aspects such as preventing residues in copolymers. It could not be said that it was an excellent polymerization solvent for general use. The present inventors have aimed to produce an ethylene copolymer that has higher polymerization activity than the above catalyst, is substantially solubilized in aliphatic or alicyclic hydrocarbons, and has a narrow molecular weight distribution and composition distribution. As a result of searching for a catalyst capable of
Moreover, even at polymerization temperatures higher than 20°C, and even when producing copolymers with a high ethylene content (ethylene content of 50% by weight or more), the copolymer has a narrow molecular weight distribution and is homogeneous in composition. As a result, the production of components insoluble in the polymerization solvent during solution polymerization is significantly suppressed, which significantly improves operational problems and makes it easier to produce copolymers with higher ethylene content than before. Furthermore, we have discovered that the production of components soluble in the polymerization solvent during slurry polymerization is significantly suppressed, resulting in a marked improvement in the yield of the copolymer.
We have arrived at the present invention. That is, the present invention has the general formula V(OR) _n Cl _3-n .
nROH (here ROH is alcohol, m is 0m
Hexane, heptane, octane or Relating to a method for producing an ethylene copolymer, which comprises copolymerizing ethylene and α-olefin in a polymerization solvent consisting of an aliphatic or alicyclic hydrocarbon having 6 to 8 carbon atoms selected from cyclohexane and cycloheptane. It is something. Vanadium trichloride used in the present invention is
X-ray powder spectra reported in ASTM15-382 (i.e. d=5.75Å, d=2.67Å, d=
It means VCl ₃ having a diffraction line (such as 1.74 Å), and also includes VCl ₃ showing a half-width broadening of the diffraction line. Examples of the alcohol used in the reaction with vanadium trichloride include methyl alcohol, ethyl alcohol, n-propyl alcohol, i-propyl alcohol, n-butyl alcohol, i-butyl alcohol, tert-butyl alcohol, hexyl alcohol, octyl alcohol, etc. Methyl alcohol, ethyl alcohol, i-propyl alcohol, etc. having a low boiling point are preferably used. As a method for obtaining the vanadium compound of the present invention, for example, in the absence of a hydrocarbon solvent, vanadium trichloride and 1 to 40 times the mole of vanadium trichloride, preferably 3 to 40 times the mole thereof,
Using 20 times the mole of alcohol, the reaction is carried out at a temperature between 0°C and the boiling point of the alcohol, and after dissolving vanadium trichloride in the alcohol, an inert hydrocarbon solvent such as n-heptane is added and the pressure is reduced under stirring. After drying, the general formula V(OR) _n Cl _3-n・nROH (here, ROH is alcohol, m is 0m1.5, and n is 0.5
A method of obtaining a solid powdery complex compound insoluble in an inert hydrocarbon solvent represented by the number expressed by After catalytically reacting preferably 3 to 30 times the mole of alcohol and dissolving vanadium trichloride in the alcohol, the reaction is allowed to proceed further at a temperature near the boiling point of the alcohol, and at the same time, excess alcohol is discharged from the system ( In this case, the inert hydrocarbon solvent used has a higher boiling point than the alcohol), the general formula V(OR) _n
Examples include a method of precipitating a solid powdery complex compound insoluble in an inert hydrocarbon solvent represented by Cl _3-n・nROH. These synthetic methods are illustrative and not limiting. The m value and n value in the general formula V(OR) _n Cl _3-n ·nROH are preferably 0 m1.5 and 0.5n3.5, more preferably 0 m1 and 1 n3. Moreover, the X-ray powder spectrum of the solid powder complex compound is completely different from that of vanadium trichloride reported in ASTM15-382, and is a spectrum unique to vanadium trichloride (i.e., d=5.75 Å, d=2.67 Å,
Diffraction lines such as d=1.74 Å) are not observed. FIG. 1 shows X-ray powder spectra of the vanadium compound of the present invention and commercially available vanadium trichloride, measured with Cu-Kα rays using a Shimadzu VD-. The broken line is the X-ray powder spectrum of the vanadium compound VCl ₃ .2.1C ₂ H ₅ OH obtained in (A) of Examples 1 to 4 of the present invention, and the solid line is the X-ray powder spectrum of commercially available vanadium trichloride. The vanadium compound of the present invention is completely different from vanadium trichloride, and has a spectrum unique to vanadium trichloride (i.e., d=5.75 Å, d=2.67 Å, d=
Diffraction lines such as 1.74 Å) are not observed. The organoaluminum compound used in the present invention is
Ethylaluminum sesquichloride is used. The vanadium compound and the organoaluminum compound are usually subjected to copolymerization without being premixed,
After premixing both, copolymerization can be carried out with or without addition of the organoaluminum compound. When producing an ethylene copolymer using the vanadium compound and the organoaluminum compound, the molar ratio of the vanadium compound and the organoaluminum compound can be generally from 1:1 to 1:100, but may be 1:1. 2 to 1:30 is preferred. Furthermore, it is well known that the activity of vanadium compounds soluble in polymerization solvents can be improved by using various polymerization activators, and a polymerization activator can be similarly used in the vanadium compound of the present invention. Examples of the polymerization activator include alkyl esters of trichloroacetic acid and tribromoacetic acid (Japanese Patent Publication No. 15052/1983), perchlorocrotonic acid esters (Japanese Patent Publication No. 9390/1989), and trichloroacetic acid or tribromoacetic acid. Examples include cellosolve esters (JP-A-53-5288), halogen compounds such as halogenated ketones, halogenated lactones, and halogen-containing cycloolefins. In carrying out the present invention, the α-olefin used for copolymerization with ethylene has the general formula CH ₂ =
It is represented by CHR (where R is a hydrocarbon group having 1 to 8 carbon atoms), and specific examples include propylene,
Butene-1, Pentene-1, Hexene-1, 4-
Examples include methylpentene-1. Among them, propylene and butene-1 can be preferably used. Further, in order to introduce an unsaturated bond into the molecule, the following polyene components can be used in copolymerization with ethylene and α-olefin. For example, 1,4-hexadiene, 1,6-octadiene, 6-methyl-1,5-heptadiene, 1,
9-octadecadiene, cycloheptadiene-
1,4, dicyclopentadiene, 5-methylene-
2-norbornene, 5-isopropenyl-2-norbornene, 2-methyl-2,5-norbornadiene, 5-ethylidene-2-norbornene, 5-isopropylidene-2-norbornene, cyclooctadiene-1,5, methyltetrahydroindene Examples thereof include 1,4-hexadiene, dicyclopentadiene, and 5-ethylidene-2-norbornene. Polymerization can be carried out by solution polymerization or slurry polymerization in the presence of a polymerization solvent. The polymerization solvent is selected from aliphatic hydrocarbons such as hexane, heptane, and octane, and alicyclic hydrocarbons such as cyclohexane and cycloheptane. It is also possible to copolymerize ethylene in liquid α-olefin using the catalyst system of the present invention in the absence of a hydrocarbon solvent. The polymerization temperature can be varied within a range, but is usually -
It is carried out at a temperature of 80 to 100°C, particularly preferably in the range of -30 to 80°C. The polymerization is carried out at atmospheric pressure or under pressure;
Batch polymerization or continuous polymerization is possible. In producing a copolymer by the method of the present invention,
In order to obtain a copolymer having an arbitrary molecular weight, a commonly used molecular weight regulator can be used. That is, diethylzinc, aryl chloride, pyridine-N-oxide,
Hydrogen and the like are often used, and hydrogen is particularly preferred. Hereinafter, the method of the present invention will be specifically explained using Examples, but the present invention is not limited thereto in any way. In addition, in the examples, the intrinsic viscosity of the copolymer is
Measurement was carried out at 135°C in tetralin, and the content of propylene or butene-1 in the copolymer was determined from the infrared absorption spectrum. In addition, the molecular weight distribution of the copolymer was measured by gel permeation chromatography.
The degree of broadening of the molecular weight distribution is expressed as _W / _N (ratio of weight average molecular weight _W to number average molecular weight _N , National
It is a standard material of the Bureau of Standards (USA).
NBS-706 (polystyrene) was measured under conditions that give _W / _N = 2.1). Moreover, the polymerization activity was expressed as the amount (g) of copolymer per 1 mmol of vanadium atoms (hereinafter abbreviated as Polymer/V). Examples 1 to 4 (A) Synthesis of vanadium compound 0.021 mol of vanadium trichloride and 0.206 mol of ethyl alcohol were added to a 100 ml flask purged with argon, and after reacting at 50°C for 1 hour with stirring,
30 ml of n-heptane was added and the mixture was dried under reduced pressure at room temperature while stirring to obtain a pale green solid powdered vanadium compound insoluble in n-heptane. When this vanadium compound was decomposed with pure water and its composition analyzed, 21% by weight of vanadium atoms, 43% by weight of chlorine atoms, and 40% by weight of C ₂ H ₅ OH were detected.
Further, when this vanadium compound was decomposed with D ₂ O (heavy water) and analyzed by GC-MS, no C ₂ H ₅ OD was detected. Therefore, this vanadium compound is
VCl ₃・2.1C ₂ H ₅ OH (general formula V(OR) _n Cl _3-n・
It was a compound where m and n of nROH are 0 and 2.1). The X-ray powder spectrum of this vanadium compound is shown in Figure 1, but it is completely different from vanadium trichloride reported in ASTM15-382, and the spectrum unique to vanadium trichloride (i.e., d = 5.75 Å, d
= 2.67 Å, d = 1.74 Å, etc.) were not observed. (B) Ethylene-propylene copolymerization A stirrer, thermometer,
After attaching a dropping funnel and a reflux condenser to reduce the pressure,
Replace with nitrogen. Example 1
Add a predetermined amount of the vanadium compound obtained in step (A) (abbreviated as component A), and add a predetermined mixed gas to it.
The mixed gas was dissolved by flowing for 10 minutes at a flow rate of 10 N/min. Next, a predetermined amount (hereinafter, the number of moles was calculated using the molecular formula (C ₂ H ₅ ) _1.5 AlCl _1.5 ) of ethylaluminum sesquichloride (abbreviated as component B) was added to start copolymerization. After polymerizing at 30℃ by flowing the above mixed gas for 30 minutes with stirring,
The components dissolved in the polymerization solvent at ℃ (hereinafter, this soluble part is abbreviated as HSP) are extracted and poured into a large amount of methanol to precipitate the copolymer.
After washing with methanol several times, it was dried under reduced pressure. In addition, if components insoluble in the polymerization solvent (hereinafter this insoluble part is abbreviated as HIP) remain in the flask,
The insoluble portion was washed several times with ml of methanol and then dried under reduced pressure. Table 1 shows the amounts of A and B components added, mixed gas composition, polymerization amount, and polymerization activity.
The propylene content of the copolymer obtained in the table,
showed _W / _N and intrinsic viscosity. In Examples 1 to 3, almost no HIP was produced, 98 to 100% was HSP, and the polymer solution was homogeneous during polymerization. The obtained copolymer had a narrower molecular weight distribution and was more homogeneous in composition than copolymers obtained using a vanadium compound soluble in a polymerization solvent (see Comparative Examples 1 to 3). On the other hand, in Example 4, the amount of HSP produced was small, with 97% being HIP,
The obtained copolymer had a narrow molecular weight distribution and was homogeneous in composition as in Examples 1 to 3. Comparative Examples 1 to 3 Instead of the vanadium compound used in Examples 1 to 4, 0.2 mm of vanadium oxytrichloride (abbreviated as component A') soluble in the polymerization solvent and ethylaluminum sesquichloride (abbreviated as component B) were added. Using 2.0 mmol, 30% of the mixed gas with the composition shown in Table 3
Copolymerization was carried out in the same manner as in (B) of Examples 1 to 4, except that component B and component A' were added after melting at .degree. The polymerization conditions, polymerization results, copolymer composition, etc. are shown in Tables 3 and 4. When the ethylene composition of the mixed gas exceeds 50 mol%, the amount of HIP, which is a component insoluble in the polymerization solvent, increases, and the polymer liquid becomes heterogeneous during polymerization. The obtained copolymer had a broader molecular weight distribution and was compositionally heterogeneous as compared to Examples 1 to 4.

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[Table] Example 5 (A) Synthesis of vanadium compound 0.033 mol of vanadium trichloride and 26 ml of n-heptane were added to a 100 ml flask purged with argon, the temperature was raised to 50°C, 0.165 mol of methyl alcohol was added, and argon was added. The reaction was carried out at 50° C. for 1 hour under stirring in an air stream. After the reaction, the supernatant was extracted with a glass filter, washed three times with 25 ml of n-heptane, and dried under reduced pressure to obtain a dark green solid powder vanadium compound insoluble in n-heptane. The composition of this vanadium compound was changed from Examples 1 to 4.
When analyzed in the same manner as in (A), vanadium atoms are 21% by weight, chlorine atoms are 42% by weight, and CH ₃ OH is 40% by weight.
No CH ₃ OD was detected. Therefore, this vanadium compound is VCl _{3.3.0CH 3} OH (general formula V
(OR) _n Cl _3-n・nROH m and n are 0 and
3.0). Further, in the X-ray powder spectrum of this compound, similar to the vanadium compounds obtained in Examples 1 to 4 (A), no spectrum peculiar to vanadium trichloride was observed. (B) Ethylene-propylene copolymerization After purging a 500 ml flask equipped with a reduction condenser with argon, add 200 ml of dried n-heptane and the above (A).
Add 0.089 mmol of the vanadium compound obtained in step 1, and adjust the temperature inside the flask to 60℃ using a thermometer and a stirrer.
The temperature rose to . Add to this ethylene 75 mol% propylene
A mixed gas of 25 mol % was flowed at a flow rate of 1 N/min for 5 minutes to dissolve the mixed gas. Next, 1.30 mmol of ethylaluminum sesquichloride was added to initiate copolymerization. Polymerization was carried out at 60°C by flowing the above mixed gas for 30 minutes with stirring, and the polymer liquid was poured into a large amount of methanol to recover the entire amount of the copolymer. The amount of the obtained copolymer was 2.05 g, and when the polymerization activity is expressed as the amount (g) of copolymer per mmol of vanadium atoms (hereinafter abbreviated as Polymer/V), Polymer/V = 23. Ta. The intrinsic viscosity of this copolymer is 1.87 dl/g, and the propylene content is 8.7
Weight %, _W / _N = 2.6. Comparative Example 4 Instead of the vanadium compound of Example 5, 0.096 mmol of vanadium oxytrichloride soluble in the polymerization solvent and ethylaluminum sesquichloride were used.
Copolymerization was carried out in the same manner as in Example 5, except that 0.95 mmol was used, and 1.79 g of copolymer was obtained.
Polymer/V was 19. The intrinsic viscosity of this copolymer was 2.48 dl/g, the propylene content was 17.7% by weight, and _W / _N = 5.4. Example 6 The vanadium compound obtained in (A) of Example 5 was 0.016
Using 0.22 mmol of ethylaluminum sesquichloride, the mixed gas composition was 50 mmol of ethylene.
Copolymerization was carried out in the same manner as in Example 5 (B) except that the mol% of propylene was 50 mol% and the polymerization temperature was 30°C. During the polymerization, HIP was not produced and only 2.51 g of HSP was obtained. Polymer/V was 157. The intrinsic viscosity of this copolymer was 3.46 dl/g, the propylene content was 30.7% by weight, and _W / _N = 2.4. Example 7 VCl ₃ .
A vanadium compound represented by 1.5CH ₃ OH (general formula V(OR) _n Cl _3-n ·nROH, where m and n are 0 and 1.5) was obtained. Further, in the X-ray powder spectrum of this compound, similar to the vanadium compounds obtained in Examples 1 to 4 (A), no spectrum peculiar to vanadium trichloride was observed. Copolymerization was carried out in the same manner as in Example 6 except that 0.019 mmol of this vanadium compound and 0.26 mmol of ethylaluminum sesquichloride were used. During the polymerization, HIP was not produced and only 1.57 g of HSP was obtained. Polymer/V was 83. The intrinsic viscosity of this copolymer is 3.91 dl/g, and the propylene content is
It was 27.1% by weight and _W / _N = 2.7. Example 8 (A) Synthesis of vanadium compound After purging one flask with a dropping funnel with argon, 0.341 mol of vanadium trichloride and 500 ml of n-heptane were added, the temperature was raised to 50°C, and 1.71 mol of ethyl alcohol was added from the dropping funnel. It was added dropwise over 10 minutes.
Next, the temperature of the oil bath was raised to 120°C, and after reaction for 2 hours under stirring in an argon stream, the supernatant liquid was extracted with a glass filter, washed three times with 250 ml of n-heptane, and dried under reduced pressure. A solid powdered vanadium compound insoluble in heptane was obtained. The composition of this vanadium compound was changed from Examples 1 to 4.
When analyzed in the same manner as in (A), it was found that vanadium atoms were 19% by weight, chlorine atoms were 31% by weight, C ₂ H ₅ OH was 35% by weight, and C ₂ H ₅ OD was 3% by weight. Therefore, this vanadium compound is V(OC ₂ H ₅ ) _0.7 Cl _2.3・2.0C ₂ H ₅
It was a compound represented by OH. Further, in the X-ray powder spectrum of this compound, similar to the vanadium compounds obtained in Examples 1 to 4 (A), no spectrum peculiar to vanadium trichloride was observed. (B) Copolymerization of ethylene-propylene 0.011 mmol of the vanadium compound obtained in (A) above and ethylaluminum sesquichloride were added.
Copolymerization was carried out in the same manner as in Example 6 except that 0.136 mmol was used. During the polymerization, no HIP was produced, and only 0.87 g of HSP was obtained. Polymer/V was 79. The intrinsic viscosity of this copolymer is 3.56 dl/g, and the propylene content is
It was 29.6% by weight, _W / _N = 2.6. Examples 9 to 11 Example 6 except that the vanadium compound obtained in (A) of Examples 1 to 4 (abbreviated as component A) and ethylaluminum sesquichloride were adjusted to a predetermined molar ratio (abbreviated as Al/V). A similar copolymerization was carried out. Fifth
The table shows the amount of component A added, Al/V, polymerization activity, composition of the obtained copolymer, etc. Note that all copolymers were only HSP. Comparative Example 5 0.02 mmol of the vanadium compound obtained in (A) of Examples 1 to 4 and 0.4 mmol of diethylaluminum chloride were used instead of ethylaluminum sesquichloride, and the composition of the mixed gas was 65 mol% ethylene and 35% propylene. Copolymerization was carried out in the same manner as in Example 6, except that the mol% was changed, and 1.2 g of a copolymer was obtained. During polymerization, the polymer liquid was heterogeneous. Polymer/V was 60. The intrinsic viscosity of this copolymer was 3.01 dl/g, the propylene content was 16.9% by weight, and _W / _N = 3.7.

[Table] Example 12 (A) Synthesis of vanadium compound Add 0.030 mol of vanadium trichloride and 50 ml of n-heptane into a 200 ml flask purged with argon.
The temperature was raised to 50°C, 0.30 mol of ethyl alcohol was added, and the oil bath was heated to 90°C. After reacting for 1 hour under stirring in an argon stream, the supernatant liquid was extracted with a glass filter, washed three times with 25 ml of n-heptane, and dried under reduced pressure to obtain a solid powdered vanadium compound insoluble in n-heptane. Ta. The composition of this vanadium compound was changed from Examples 1 to 4.
When analyzed in the same manner as in (A), it was found that vanadium atoms were 19% by weight, chlorine atoms were 37% by weight, C ₂ H ₅ OH was 43% by weight, and C ₂ H ₅ OD was 3% by weight. Therefore, this vanadium compound is V(OC ₂ H ₅ ) _0.2 Cl _2.8・2.5C ₂ H ₅
It was a compound represented by OH. Further, in the X-ray powder spectrum of this compound, similar to the vanadium compounds obtained in Examples 1 to 4 (A), no spectrum peculiar to vanadium trichloride was observed. (B) Copolymerization of ethylene-butene-1 Using 0.051 mmol of the vanadium compound obtained in (A) above and 0.66 mmol of ethylaluminum sesquichloride, the composition of the mixed gas was changed to ethylene.
Copolymerization was carried out in the same manner as in Example 6, except that the proportions were 83.5 mol % and butene - 116.5 mol %, to obtain 2.50 g of a copolymer. Polymer/V was 49. The intrinsic viscosity of this copolymer was 2.49 dl/g, the butene-1 content was 14.1% by weight, and _W / _N = 2.3. Comparative Example 6 Instead of the vanadium compound of Example 12, 0.043 mmol of vanadium oxytrichloride soluble in the polymerization solvent and ethylaluminum sesquichloride were used.
Copolymerization was carried out in the same manner as in Example 12, except that 0.40 mmol was used, and 2.02 g of copolymerization was obtained.
Polymer/V was 47. The intrinsic viscosity of this copolymer was 6.56 dl/g, the butene-1 content was 9.4% by weight, and _W / _N = 6.8. Example 13 n- of perchlorocrotonic acid as a polymerization activator
Ethylene-propylene copolymerization was carried out using butyl ester (abbreviated as component C). That is, 0.195 mmol of C component and Examples 1 to 4.
Examples 1 to 4 (B Copolymerization was carried out in the same manner as in ). During polymerization, HIP is not produced, only HSP is 36.50
g was obtained. Polymer/V was 384. The intrinsic viscosity of this copolymer was 2.83 dl/g, the propylene content was 27.1% by weight, and _W / _N = 2.9. Example 14 Using the vanadium compounds obtained in (A) of Examples 1 to 4, ternary copolymerization of ethylene/propylene/5-ethylidene-2-norbornene was carried out. That is, in (B) of Examples 1 to 4, Examples 1 to 4
In addition to 0.171 mmol of the vanadium compound obtained in step 4 (A) and 2.57 mmol of ethylaluminum sesquichloride, 5 mmol of 5-ethylidene-2-norbornene was used, and a mixed gas of 50 mol% ethylene and 50 mol% propylene was heated at 10 N/min. , Example 1~ except that hydrogen was further used at a flow rate of 1N/min.
Ethylene/propylene/5-
Ternary copolymerization of ethylidene-2-norbornene was carried out. After polymerization, 30 ml of methanol was added to stop the reaction, and the mixture was poured into a large amount of methanol to precipitate a copolymer. This precipitate was washed several times with 50 ml of methanol and then dried under reduced pressure to obtain 12.40 g of a copolymer. Polymer/V was 73. The intrinsic viscosity of this copolymer is 1.79 dl/g, the propylene content is 23.7% by weight, the iodine number is 6.5, and _{the W} /
M _N =2.8.

[Brief explanation of the drawing]

FIG. 1 is an X-ray powder spectrum of the vanadium compound of the present invention and commercially available vanadium trichloride.
The broken line is the X-ray powder spectrum of the vanadium compound VCl ₃ .2.1C ₂ H ₅ OH obtained in (A) of Examples 1 to 4 of the present invention, and the solid line is the X-ray powder spectrum of commercially available vanadium trichloride.
FIG. 2 is a flowchart to aid in understanding the present invention. This flowchart is a representative example of the embodiment of the present invention, and the present invention is not limited thereto.

Claims (1)

[Claims] 1 (A) General formula V(OR) _n Cl _3-n・nROH (here, ROH is alcohol, m is 0m
Hexane, heptane,
Production of an ethylene copolymer characterized by copolymerizing ethylene and α-olefin in a polymerization solvent consisting of an aliphatic or alicyclic hydrocarbon having 6 to 8 carbon atoms selected from octane, cyclohexane, and cycloheptane. Method. 2. The method for producing an ethylene copolymer according to claim 1, wherein the vanadium compound (A) is VCl ₃ .nROH. 3 (A) Claim 1 in which the vanadium compound is a solid powder complex compound obtained by dissolving vanadium trichloride in alcohol and then discharging excess alcohol out of the system at a temperature near the boiling point of the alcohol. A method for producing an ethylene copolymer as described in 2.