JPH0645659B2 - Manufacturing method of ultra high molecular weight ethylene-gen copolymer - Google Patents

Description

TECHNICAL FIELD The present invention relates to a process for producing an ultrahigh molecular weight ethylene / diene copolymer (hereinafter referred to as ultrahigh molecular weight polyethylene), which is a type of ultrahigh molecular weight polyethylene, More specifically, it relates to a method for producing ultra-high molecular weight polyethylene which contains a large amount of double bonds and is easily cross-linked and modified.

(Problems to be solved by conventional techniques and inventions) The so-called ultra-high molecular weight polyethylene, which has a remarkably high molecular weight of about 1,000,000 or more, has excellent impact resistance and wear resistance, and also has a self-lubricating characteristic engineering As plastics, it is used in a wide range of fields such as food machinery such as hoppers, silos, various gears, lining materials, ski linings, civil engineering machinery, chemical machinery, agriculture, mining, and sports / registry.

In addition, since ultra-high molecular weight polyethylene has a much higher molecular weight than general-purpose polyethylene, if it can be highly oriented, a stretched product with higher strength and elasticity than ever before can be obtained. Various studies have been made to increase the orientation for the purpose of obtaining.

However, although ultra-high molecular weight polyethylene has the above-mentioned characteristics, it has drawbacks such as poor heat resistance (melting point is relatively low at around 140 ° C.), poor adhesion and compatibility with other resins. In order to improve these drawbacks, crosslinking by peroxide or radiation (Japanese Patent Application Laid-Open No. 60-59172, Japanese Patent Application Laid-Open No. 60-1).
18725), and the introduction of polar groups (JP-A-60-2407).
34), a specific filler composition (JP-A-59-1811).
50), surface treatment (JP-A-60-146078), and the like.

Although these proposals show an improvement effect, they are still sufficient. For example, in the case of cross-linking, the cross-linking efficiency is poor, a large amount of peroxide is required, and the irradiation dose must be increased. However, there is a problem that the polar group introduced is limited even if the polar group is introduced.

Ultrahigh molecular weight polyethylene containing a double bond obtained by copolymerization of ethylene and a diene compound is conceivable as one method for solving the above-mentioned problems, but usually, under the polymerization conditions for producing ultrahigh molecular weight polyethylene, the diene compound is simply used. The copolymerizability of the diene compound is poor only by increasing the amount of
It is not possible to efficiently introduce a double bond based on a diene compound into the resulting ultra high molecular weight polyethylene.

(Means for Solving Problems) As a result of the above, the present inventors have made diligent studies to solve these problems, and found that ethylene and a diene compound were combined with a specific catalyst and specific copolymerization conditions. Thus, it was discovered that ultrahigh molecular weight polyethylene containing a large amount of double bonds can be easily obtained.

That is, the present invention copolymerizes ethylene and at least one diene compound with a catalyst comprising a solid catalyst component comprising a titanium compound or a titanium compound and a vanadium compound supported on an inorganic solid compound containing magnesium, and an organoaluminum compound, In a method for producing an ultrahigh molecular weight polyethylene having an intrinsic viscosity of 5 d / g or more in decalin at 135 ° C., the diene compound / ethylene (molar ratio) at the time of polymerization is 0.5 or more, and Ti in the solid catalyst component is
And a V / diene compound (molar ratio) of 1.0 × 10 ⁻⁵ or more, and to a process for producing ultrahigh molecular weight polyethylene.

The ultra-high molecular weight polyethylene obtained according to the present invention has a high content of double bonds of 0.1 mol% or more, and the reactivity of this double bond is utilized to facilitate various modifications and cross-linking of the ultra-high molecular weight polyethylene. It can be carried out.

Hereinafter, the method for producing the ultrahigh molecular weight polyethylene of the present invention will be specifically described.

Hydrogen concentration of ethylene and diene compound 0 to about 10 mol%
By polymerizing in a solvent or in the gas phase,
Ultrahigh molecular weight polyethylene having an intrinsic viscosity of 5 d / g or more, preferably 10 d / g to 30 d / g in decalin at ℃ is produced. Those having an intrinsic viscosity of less than 5 d / g are not preferable because the original abrasion resistance and mechanical strength of ultrahigh molecular weight polyethylene are poor.

As the diene compound, 5-vinyl-2-norbornene, 5-
Ethylidene-2-norbornene, dicyclopentadiene,
Non-conjugated polycyclic dienes such as norbornadiene and propenyl norbornene, 1,4-pentadiene, 1,4-hexadiene, 1,5-hexadiene, 3-methyl-1,4-pentadiene, 1,4-peptadiene, 1, Non-conjugated aliphatic dienes such as 5-heptadiene, 1,6-heptadiene, 3-methyl-1,4-hexadiene, 3-methyl-1,5-hexadiene, 1,3-butadiene, isoprene, 1,3- Examples thereof include conjugated aliphatic dienes such as pentadiene, 1,3-hexadiene, 2,3-dimethyl-1,3-butadiene, and 2-phenyl-1,3-butadiene.

The polymerization catalyst used at this time is at least Mg, Ti
Alternatively, it is composed of a solid catalyst component containing Ti and V and an organometallic compound (described later), and the polymerization pressure is 0 to 70.
kg / cm ² · G, polymerization temperature 0 to 90 ° C, preferably 20 to
It is carried out in a solvent at 80 ° C. or in the gas phase. As the polymerization solvent, an organic solvent inert to the Ziegler type catalyst is used. Specifically, butane, pentane, hexane, heptane, octane, saturated hydrocarbons such as cyclohexane, benzene,
Toluene, aromatic hydrocarbons such as xylene, etc. can be mentioned, and further high-boiling organic solvents such as decalin, tetralin, decane, kerosene, etc. can also be mentioned depending on the necessity of molding processing of the obtained ultrahigh molecular weight polyethylene. .

In the present invention, in order to copolymerize ethylene and at least one diene compound to produce an ultrahigh molecular weight polyethylene having a high double bond content, the diene compound / ethylene (molar ratio) is 0.5 or more, preferably 1.0 or more. It is necessary to polymerize under the conditions that the Ti and V / diene compounds (molar ratio) in the solid catalyst component are 1.0 × 10 ⁻⁵ or more, preferably 2.0 × 10 ⁻⁵ or more. However, if either of these conditions is not satisfied, the double bond content in the ultrahigh molecular weight polyethylene is reduced.

In the calculation of the above molar ratio, the molar amount of dissolved ethylene is used in the case of polymerization in a solvent.

Further, α-olefin other than ethylene may be used as the third polymerization component, and the α-olefin at this time may be propylene, butene-1,4-methyl-pentene-1, hexene-1, octene-. For example, those used for the copolymerization of ethylene with a conventional Ziegler type catalyst can be used.

Next, the catalyst used for producing the ultra-high molecular weight polyethylene of the present invention comprises a solid catalyst component containing at least Mg, Ti or Ti and V and an organoaluminum compound.

Here, the solid catalyst component is an inorganic solid compound containing magnesium supported with titanium or a titanium compound and a vanadium compound by a known method.

The inorganic solid compound containing magnesium is metallic magnesium, magnesium hydroxide, magnesium carbonate, magnesium oxide, magnesium chloride, etc., and a double salt containing a metal and a magnesium atom selected from silicon, aluminum, and calcium, a complex oxide, Carbonates, chlorides, hydroxides and the like, as well as these inorganic solid compounds, organic oxygen-containing compounds such as water, alcohols, phenols, ketones, aldehydes, carboxylic acids, esters, polysiloxanes and acid amides; metal alkoxides. , Inorganic oxygenates such as metal oxyacid salts; thiols,
Organic sulfur-containing compounds such as thioethers; sulfur dioxide,
Inorganic sulfur-containing compounds such as sulfur trioxide and sulfuric acid; benzene,
A monocyclic or polycyclic aromatic hydrocarbon compound such as toluene, xylene, anthracene, or phenols; treated or reacted with a halogen-containing compound such as chlorine, hydrogen chloride, a metal chloride, or an organic halide.

Examples of the titanium compound supported on the inorganic solid compound include titanium halides, alkoxy halides,
Alkoxides, halogenated oxides, etc., and tetravalent or trivalent titanium compounds are preferable. Specific examples of the tetravalent titanium compound include Ti (OR) _n X _4-n (wherein R represents an alkyl group having 1 to 20 carbon atoms, an aryl group or an aralkyl group, and X represents a halogen atom). And n is 0 ≦ n ≦ 4) are preferable, and titanium tetrachloride, titanium tetrabromide, titanium tetraiodide, monomethoxytrichlorotitanium, dimethoxydichlorotitanium, trimethoxymonochlorotitanium, tetra Methoxytitanium, monoethoxytrichlorotitanium, diethoxydichlorotitanium, triethoxymonochlorotitanium, tetraethoxytitanium, monoisopropoxytrichlorotitanium,
Diisopropoxydichlorotitanium, triisopropoxymonochlorotitanium, tetraisopropoxytitanium, monobutoxytrichlorotitanium, dibutoxydichlorotitanium, monopentoxytrichlorotitanium, monophenoxytrichlorotitanium, diphenoxydichlorotitanium, triphenoxymonochlorotitanium. , Tetravalent titanium compounds such as tetraphenoxy titanium. The trivalent titanium compound is a trivalent titanium compound obtained by reducing titanium tetrahalide such as titanium tetrachloride or titanium tetrabromide with hydrogen, aluminum, titanium or an organometallic compound of Group I to III metal of the periodic table. Valent titanium compound; general formula Ti (OR)
_m X _4-m (wherein R represents an alkyl group, an aryl group or an aralkyl group having 1 to 20 carbon atoms, X represents a halogen atom, and m is 0 <m <4). And a trivalent titanium compound obtained by reducing the halogenated alkoxytitanium with an organometallic compound of a metal of groups I to III of the periodic table. Of these titanium compounds, tetravalent titanium compounds are particularly preferable. As the vanadium compound, a tetravalent vanadium compound such as vanadium tetrachloride, a vanadium oxytrichloride, a pentavalent vanadium compound such as orthoalkylvanadate, and a trivalent vanadium compound such as vanadium trichloride. Is mentioned. Specific solid catalyst components include Japanese Patent Publication No. 51-3514, Japanese Patent Publication No. 50-23864, and Japanese Patent Publication No. 51-15.
No. 2, JP-B-52-15111, JP-A-49
-106581, JP-B-52-11710, JP-B-51-153, JP-A-56-9590
Specific examples are given in Japanese Patent Publication No. 9 and the like.

Further, as the other solid catalyst component, for example, a reaction product of a Grignard compound and a titanium compound can be used. JP-B-50-39470, JP-B-54-12953, JP-B-54-12954, 57-7
Specific examples include those described in Japanese Patent No. 9009,
In addition, JP-A-56-47407 and JP-A-57
A solid catalyst component in which an inorganic oxide is used in combination with an optionally used organic carboxylic acid ester described in JP-A-187305 and JP-A-58-21405 can also be used.

The organoaluminum compound of the present invention has the general formula R ₃ A
1, R ₂ AlX, RAlX ₂ , R ₂ AlOR, RAl (OR) X and R ₃ Al ₂ X ₃ (wherein R represents an alkyl group, an aryl group or an aralkyl group having 1 to 20 carbon atoms, and X is A halogen atom and R may be the same or different) are preferable, and triethyl aluminum, triisobutyl aluminum, trihexyl aluminum, trioctyl aluminum, diethyl aluminum chloride, diethyl aluminum ethoxide, Ethyl aluminum sesquichloride, and mixtures thereof. The amount of the organic aluminum compound used is not particularly limited, but is usually 0.1 to 100 relative to the titanium compound.
It can be used 0 times by mole.

The above catalyst system is used to synthesize the ultrahigh molecular weight polyethylene of the present invention.

Prior to the polymerization reaction of the present invention, the polymerization reaction may be carried out after contacting α-olefin with the catalyst system of the present invention.

Hereinafter, the present invention will be specifically described in detail with reference to Examples, but the present invention is not limited thereto.

Example 1 (a) Preparation of solid catalyst component Commercially available anhydrous magnesium chloride (10 g), silicon tetraethoxide (3.3 g) and a stainless steel pot having an internal volume of 400 m containing 25 stainless steel balls each having a diameter of 1/2 inch were used. Add 0.7 g of phosphorus oxychloride and perform ball milling at room temperature for 5 hours in a nitrogen atmosphere.
Thereafter, 2 g of titanium tetrachloride was added, and ball milling was further performed for 16 hours. 1 g of the solid catalyst component obtained after ball milling contained 32 mg of titanium.

(b) Polymerization 2 An autoclave with a stainless steel induction stirrer was replaced with nitrogen, 1000 m of hexane was added, 3.3 mmol of triethylaluminum and 50 mg of the solid catalyst component were added, and the temperature was raised to 70 ° C. with stirring. The system becomes 1.3 kg / cm ² · G by the vapor pressure of hexane, and then 135 g of 5-vinyl-2-norbornene is added together with ethylene, and ethylene is added until the total pressure reaches 10 kg / cm ² · G to carry out polymerization. Start the autoclave pressure at 10kg /
Polymerization was carried out for 1 hour so as to be maintained at cm ² · G. The 5-vinyl-2-norbornene / ethylene molar ratio during the polymerization was 1.2, and the Ti / 5-vinyl-2-norbornene molar ratio in the solid catalyst component was 3 × 10 ⁻⁵ .

After the completion of the polymerization, the polymer slurry was transferred to a beaker, hexane and unreacted 5-vinyl-2-norbornene were removed under reduced pressure, the intrinsic viscosity was 14.9 d / g (135 ° C, in decalin), and the density was 0.
930, 62 g of white ethylene copolymer resin with a bulk density of 0.26
Got

According to infrared spectroscopy, the content of 5-vinyl-2-norbornene in the copolymer was 0.18 mol%.

The autoclave with a stirless steel induction stirrer of Comparative Example 12 was purged with nitrogen, 1000 m of hexane was put thereinto, 1 mmol of triethylaluminum and 15 mg of the solid catalyst component obtained in Example 1 (a) were added, and the mixture was heated to 70 ° C. with stirring. The temperature was raised. Polymerization was initiated by pouring the system to 1.3 kg / cm ² · G with the vapor pressure of hexane, and polymerization was carried out for 1 hour while maintaining the pressure of the autoclave at 10 kg / cm ² · G.

After completion of the polymerization, the polymer slurry was transferred to a beaker, and hexane was removed under reduced pressure to obtain 110 g of a white ethylene copolymer resin having an intrinsic viscosity of 19.7 d / g (135 ° C. in decalin), a density of 0.940 and a bulk density of 0.32.

No double bond was present in the copolymer by infrared spectroscopy.

The autoclave with a stirless steel induction stirrer of Comparative Example 2 was replaced with nitrogen, 1000 m of hexane was added, 1 mmol of triethylaluminum and 1 mg of the solid catalyst were added, and the temperature was raised to 70 ° C with stirring. The system becomes 1.3 kg / cm ² · G due to the vapor pressure of hexane, and then 27 g of 5-vinyl-2-norbornene is added together with ethylene, and ethylene is added until the total pressure reaches 10 kg / cm ² · G for polymerization. Started. Thereafter, ethylene was continuously introduced so that the total pressure would be 10 kg / cm ² · G, and polymerization was carried out for 1 hour. The molar ratio of 5-vinyl-2-norbornene / ethylene during polymerization is
It was 0.24, and the Ti / 5-vinyl-2-norbornene molar ratio in the solid catalyst component was 4.5 × 10 ⁻⁵ .

After the polymerization was completed, the polymer slurry was transferred to a beaker, and hexane and unreacted 5-vinyl-2-norbornene were removed under reduced pressure to obtain an intrinsic viscosity of 18.2 d / g (135 ° C, in decalin) and a density of 0.
937, and 65 g of a white ethylene copolymer having a bulk density of 0.30 was obtained.

According to infrared spectroscopy, the content of 5-vinyl-2-norbornene in the copolymer was 0.038 mol%.

Comparative Example 3 135 g of 5-vinyl-2-norbornene in Comparative Example 2
Polymerization was performed in the same manner as in Comparative Example 2 except that it was used. 5-Vinyl-2-norbornene during polymerization /
The ethylene molar ratio is 1.2, and Ti / 5- in the solid catalyst component
The vinyl-2-norbornene molar ratio was 0.9 × 10 ^-5 .

After completion of the polymerization, the polymer slurry was transferred to a beaker, and hexane and unreacted 5-vinyl-2-norbornene were removed under reduced pressure to obtain an intrinsic viscosity of 16.0 d / g (135 ° C in decalin) and a density of 0.
935, and 45 g of white ethylene having a bulk density of 0.25 was obtained.

According to infrared spectroscopy, the content of 5-vinyl-2-norbornene in the copolymer was 0.06 mol%.

Example 2 Polymerization was carried out in the same manner as in Example 1 (b) except that 2.6 mmol of triethylaluminum and 40 mg of a solid catalyst component were used in Example 1 (b). The molar ratio of 5-vinyl-2-norbornene / ethylene at the time of polymerization was 1.2, and the molar ratio of Ti / 5-vinyl-2-norbornene in the solid catalyst component was 2.3 × 10 ⁻⁵ .

Polymer yield is 50g, intrinsic viscosity is 15.5d / g
(135 ℃, in decalin), density is 0.931, bulk density is
It was 0.26.

According to infrared spectroscopy, the content of 5-vinyl-2-norbornene in the copolymer was 0.16 mol%.

Example 3 (a) Production of solid catalyst component Same as Example 1 (a) except that 1.9 g of boron triethoxide was used in place of 3.3 g of silicon tetraethoxide in Example 1 (a). A catalyst was produced by the method.
1 g of the obtained solid catalyst component contained 35 mg of titanium.

(b) Polymerization Using the same autoclave as in Example 1 (b), 1000 m of hexane was added, 5 mmol of diethylaluminum chloride and 50 mg of the solid catalyst component were added, and the temperature was raised to 70 ° C with stirring. 1.3 kg vapor pressure of hexane
/ Cm ² · G, but then 5-vinyl-2-norbornene 1
Pour 35g together with ethylene, total pressure of ethylene 1
Polymerization was initiated by squeezing until it reached 0 kg / cm ² · G.
Thereafter, ethylene was continuously introduced so that the total pressure would be 10 kg / cm ² · G, and polymerization was carried out for 1 hour. 5- during polymerization
The vinyl-2-norbornene / ethylene molar ratio is 1.2,
The Ti / 5-vinyl-2-norbornene molar ratio in the solid catalyst component was 3.3 × 10 ⁻⁵ .

Polymer yield is 35g, intrinsic viscosity is 22.3d / g
(135 ℃, in decalin), density is 0.932, bulk density is
It was 0.24.

According to infrared spectroscopy, the content of 5-vinyl-2-norbornene in the copolymer was 0.11 mol%.

Examples 4 to 6 Polymerization was performed in the same manner as in Example 1 (b) except that the comonomer shown in Table 1 was used instead of 5-vinyl-2-norbornene in Example 1 (b). . The results are shown in Table 1.

Example 7 (a) Production of solid catalyst component VO was used instead of 2.0 g of titanium tetrachloride in Example 1 (a).
A catalyst was prepared in the same manner as in Example 1 (a) except that 0.5 g of (OC ₂ H ₅ ) ₃ and 2.0 g of titanium tetrachloride were used. 1 g of the obtained solid catalyst component contained 7.6 mg of vanadium and 30.6 mg of titanium.

(b) Polymerization Using the same autoclave as in Example 1 (b), 1000 m of hexane was added, 6 mmol of triethylaluminum and 70 mg of the solid catalyst component were added, and the temperature was raised to 70 ° C with stirring. Hexane vapor pressure of 1.3 kg / cm ²
G, but then 5-vinyl-2-norbornene 155g
With ethylene, total pressure of ethylene 10kg /
cm ² · Polymerization started by Harikon until G, KoTsuta polymerization for 3 hours so as to maintain the pressure of the autoclave to 10 kg / cm ² · G. The 5-vinyl-2-norbornene / ethylene molar ratio during polymerization was 1.3, and the Ti and V / 5-vinyl-2-norbornene molar ratios in the solid catalyst component were
It was 4.2.

The polymer yield was 126 g and the intrinsic viscosity was 15.1 d /
g (135 ° C., in decalin), density was 0.932, and bulk density was 0.28.

According to infrared spectroscopy, the content of 5-vinyl-2-norbornene in the copolymer was 0.15 mol%.

Example 8 (a) Production of solid catalyst component Commercially available anhydrous magnesium oxide 10 g and silicon tetraethoxide 3.3 g in a stainless steel pot having an internal volume of 400 m containing 25 stainless steel balls having a diameter of 1/2 inch. And phosphorus oxyoxide.
7 g was added, ball milling was carried out at room temperature for 5 hours in a nitrogen atmosphere, and then 2 g of titanium tetrachloride was added, and further 16
I did ball milling for hours. 1 g of the solid catalyst component obtained after ball milling contained 32 mg of titanium.

(b) Polymerization 2 A stainless steel autoclave equipped with an electromagnetic induction stirrer was replaced with nitrogen, 1000 m of hexane was added, and 3.3 mmol of triethylaluminum and the solid catalyst component 5
0 mg was added, and the temperature was raised to 70 ° C. with stirring. The system becomes 1.3 kg / cm ² · G by the vapor pressure of hexane, but then 5
-135 g of vinyl-2-norbornene was added together with ethylene, and ethylene was added until the total pressure reached 10 kg / cm ² · G to start the polymerization, and the autoclave pressure was adjusted to 1
Polymerization was carried out for 1 hour while keeping it at 0 kg / cm ² · G. The 5-vinyl-2-norbornene / ethylene molar ratio at the time of polymerization was 1.2, and Ti / in the solid catalyst component /
The 5-vinyl-2-norbornene ratio was 3 × 10 ^-5 .

After the polymerization was completed, the polymer slurry was transferred to a beaker, and hexane and unreacted 5-vinyl-2-norbornene were removed under reduced pressure to obtain an intrinsic viscosity of 15.8 d / g (135 ° C. in decalin), a density of 0.932, and a bulk density. 55 g of 0.25 white polyethylene copolymer resin was obtained.

According to infrared spectroscopy, the content of 5-vinyl-2-norbornene in the copolymer was 0.16 mol%.

Example 9 (a) Production of solid catalyst component Commercially available anhydrous magnesium chloride 10 g and silicon tetraethoxide 3.3 g in a stainless steel pot having an internal volume of 400 m containing 25 stainless steel balls each having a diameter of 1/2 inch. And phosphorus oxychloride.
7 g was added, ball milling was carried out at room temperature for 5 hours in a nitrogen atmosphere, and then 2 g of titanium tetrachloride was added, and further 16
I did ball milling for hours. After ball milling, 1 g of the solid catalyst component obtained contained 32 mg of titanium.

(b) Polymerization Polymerization was carried out in the same manner as in Example 8. The 5-vinyl-2-norbornene / ethylene molar ratio during the polymerization was 1.
2, and the Ti / 5-vinyl-2-norbornene ratio in the solid catalyst component was 3 × 10 ⁻⁵ .

Polymer yield was 52 g and intrinsic viscosity was 15.2 d.
/ G, the density was 0.935, the bulk density was 0.27.

According to infrared spectroscopy, the content of 5-vinyl-2-norbornene in the copolymer was 0.14 mol%.

Example 10 (a) Production of solid catalyst component Commercially available anhydrous magnesium chloride 10 g and silicon tetraethoxide 2.3 g were placed in a stainless steel pot having an internal volume of 400 m containing 25 stainless steel balls each having a diameter of 1/2 inch. And phosphorus oxychloride 1.
7 g was added, ball milling was performed at room temperature for 5 hours in a nitrogen atmosphere, and then 3.6 g of chlorotributoxytitanium was added.
Was added, and ball milling was further performed for 16 hours. After ball milling, 1 g of the solid catalyst component obtained contained 32 mg of titanium.

(b) Polymerization Polymerization was carried out in the same manner as in Example 8. The 5-vinyl-2-norbornene / ethylene molar ratio during the polymerization was 1.
2, and the Ti / 5-vinyl-2-norbornene ratio in the solid catalyst component was 3 × 10 ⁻⁵ .

Polymer yield was 52 g, intrinsic viscosity 16.3 d
/ G, the density was 0.933, the bulk density was 0.26.

According to infrared spectroscopy, the content of 5-vinyl-2-norbornene in the copolymer was 0.15 mol%.

Example 11 (a) Production of solid catalyst component 10 g of commercially available anhydrous magnesium chloride and 3.3 g of silicon tetraethoxide were placed in a stainless steel pot having an internal volume of 400 m containing 25 stainless steel balls each having a diameter of 1/2 inch. And phosphorus oxychloride.
7 g was added, ball milling was performed at room temperature for 5 hours in a nitrogen atmosphere, and then titanium trichloride (TiCl ₃ · 1 / 3A
2.5 g of 1Cl ₃ ) was added, and ball milling was performed for 16 hours. After ball milling, 1 g of the solid catalyst component obtained contained 37 mg of titanium.

(b) Polymerization Polymerization was carried out in the same manner as in Example 8. The 5-vinyl-2-norbornene / ethylene molar ratio during the polymerization was 1.
2, and the Ti / 5-vinyl-2-norbornene ratio in the solid catalyst component was 3.5 × 10 ⁻⁵ .

Polymer yield was 66 g, intrinsic viscosity was 18.2 d
/ G, the density was 0.931, the bulk density was 0.27.

According to infrared spectroscopy, the content of 5-vinyl-2-norbornene in the copolymer was 0.16 mol%.

Example 12 (a) Production of solid catalyst component 10 g of commercially available anhydrous magnesium chloride and 3.3 g of silicon tetraethoxide were placed in a stainless steel pot having an internal volume of 400 m containing 25 stainless steel balls each having a diameter of 1/2 inch. And phosphorus oxychloride.
7 g was added, ball milling was performed at room temperature for 5 hours in a nitrogen atmosphere, 0.5 g of vanadium tetrachloride and 2 g of titanium tetrachloride were added, and ball milling was further performed for 16 hours. 1 g of solid catalyst component obtained after ball milling
Contained 8 mg of vanadium and 31 mg of titanium.

(b) Polymerization Polymerization was carried out in the same manner as in Example 8. The 5-vinyl-2-norbornene / ethylene molar ratio during the polymerization was 1.
2, and the Ti and V / 5-vinyl-2-norbornene ratio in the solid catalyst component was 3.7 × 10 ⁻⁵ .

Polymer yield is 50 g, intrinsic viscosity is 13.6 d
/ G, the density was 0.930, the bulk density was 0.24.

According to infrared spectroscopy, the content of 5-vinyl-2-norbornene in the copolymer was 0.17 mol%.

[Brief description of drawings]

FIG. 1 is a flow chart for explaining the present invention.

Claims (1)

[Claims] 1. Copolymerizing ethylene and at least one diene compound with a catalyst composed of an organic aluminum compound and a solid catalyst component comprising a titanium compound or a titanium compound and a vanadium compound supported on an inorganic solid compound containing magnesium, A method for producing an ultrahigh molecular weight polyethylene having an intrinsic viscosity of 5 d / g or more in decalin at 135 ° C., wherein the diene compound / ethylene (molar ratio) at the time of polymerization is 0.5 or more, and Ti and V / diene in the solid catalyst component are used. A process for producing an ultra-high molecular weight ethylene / diene copolymer, characterized in that the compound (molar ratio) is 1.0 × 10 ⁻⁵ or more.