JPS5956412A - Production of unsaturated copolymer - Google Patents

Abstract

PURPOSE:To obtain a fish eye-free unsaturated copolymer excellent in moldability, environmental stress cracking resistance, rigidity, etc., by carrying out the copolymerization reaction in two stages under specified conditions, in copolymerizing ethylene with a nonconjugated diene in the presence of a catalyst. CONSTITUTION:Ethylene alone or together with other alpha-olefins is copolymerized with a nonconjugated diene (e.g., 1,4-pentadiene) in the presence of a caatalyst comprising a transition metal compound component and an organoaluminum compound. The copolymerization reaction is carried out in two stage, and in one of these two stages, there is formed a polymer A having a viscosity-average MW of 100,000-600,000, a diene content of 0.01-10wt%, and an alpha-olefin content of below 10wt%. In the other stage, there is formed a polymer B having a viscosity-average MW of 10,000-40,000, and a diene content and an alpha-olefin content lower than those of polymer A. The purpose copolymer is obtained by conducting the above two-stage polymerization such that the weight ratio of polymer A to polymer B is 3/7-7/3 can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing an ethylene polymer having pendant double bonds. The present invention relates to a method for producing a polymer that has excellent moldability, ie, rigidity, and is free from fish eyes.

Conventionally, polyethylene produced using a polymedia produced using a titanium-based catalyst has excellent extrudability, but E80R
It had the disadvantage that it was inferior to others.

In addition, in melting behavior, there was generally a correlation between melt tension and ballast effect (die swell).

The present inventors conducted a loading study to obtain an ethylene copolymer with improved mechanical and melting properties, and found that a two-stage polymerization process using a non-conjugated diene as a copolymerization component of ethylene was conducted. Through much effort, the inventors discovered that a copolymer with excellent various physical properties could be obtained and arrived at the present invention.

An object of the present invention is to provide a method for producing an ethylene copolymer having good extrudability, small die swelling and high melt tension.

Another object of the present invention is to provide a method for producing an ethylene copolymer that has excellent EISOR and rigidity and does not cause fish eyes.

Still another object of the present invention is to provide a method for producing an ethylenically unsaturated copolymer having pendant double bonds that can be chemically modified and has high chemical reactivity.

The object of the present invention is to provide a method for producing an unsaturated copolymer by copolymerizing ethylene or ethylene and other a-olefins with a non-conjugated diene in the presence of a catalyst consisting of a transition metal compound component and an organoaluminum compound. The copolymerization reaction is carried out in two stages, and in either stage 1, the viscosity average molecular weight is 10,000 to 20,000, and the diene content is 110,000.
．． 01 to 70% by weight, α-olefin content of 10% by weight or less Both amounts produce a polymer (B) which is much larger than the polymer (A), and the polymer (
A) and polymer (B) produced in a weight ratio of 3/7 to 7/3.
This is achieved by a method for producing an unsaturated copolymer characterized by the following.

The present invention will be explained in detail below.

In the present invention, a catalyst comprising a transition metal compound component and an organoaluminum compound is used.

As the transition metal compound component, a known catalyst component supported on a magnesium compound is used. Preferably, a solid component containing titanium, magnesium and a halogen is used, and particularly preferably, a) magnesium compound is used. An oxygen-containing organic compound, a reaction product of an oxygen-containing organic compound of titanium and an aluminum halide compound, or b) a reaction product of an oxygen-containing organic compound of magnesium and a titanium halide compound are used.

The oxygen-containing organic compound of magnesium used in preparing the reaction products of e,) b and b) has the general formula % (wherein R represents an alkyl group, an aryl group or a cycloalkyl group). , X represents a halogen atom, and m is 1 or co), specifically, jetoxymagnesium.

dimethoxymagnesium, diphenoxymagnesium,
Examples include ethoxymagnesium chloride, phenoxymagnesium chloride, ethoxymagnesium bromide, and ethoxymagnesium iodide.

-Raw- Among them, jetoxymagnesium is preferred.

The oxygen-containing organic compound of titanium used to prepare the reaction product of a) has the general formula % formula % () (wherein R and X are synonymous with the above general formula [!],
n is 11λ, 3 or g. ),
Specifically, tetraethoxytitanium, tetrabutoxytitanium, jetoxytitanium dichloride, dibutoxytitanium dichloride, triethoxytitanium chloride, tryptoxytitanium chloride, ethoxytitanium trichloride, butoxytitanium trichloride.

Methoxytitanium tribromide, among others.

Trypoxytitanium chloride is preferred.

As the titanium halogen compound used in preparing the reaction product b), in the general formula [[[), n
is 0. /, 2 or 3 are mentioned. Specific examples include titanium tetrachloride, titanium tetrabromide, titanium tetraiodide, ethoxytitanium trichloride, methoxytitanium tribromide, jetoxytitanium dichloride, etc. Titanium halides are preferred.

The aluminum halogen compound used to prepare the reaction product of a) has the general formula % (wherein R and X have the same meaning as the general formula CI),
j is a positive number smaller than 3 by υ. ) are listed. Specifically, ethylaluminum dichloride,
Examples include diethylaluminium chloride and propylaluminum dichloride, with ethylaluminum sesquichloride being particularly preferred.

To prepare the reaction product a), an oxygen-containing organic compound of magnesium and an oxygen-containing organic compound of titanium are mixed and heated to io~/lO<0>C.

If necessary, add alcohol such as ethanol, butanol, or octatool to prepare a uniform liquid, and then add an inert hydrocarbon solvent to the resulting solution. The reaction product a) can be obtained as a precipitate. The quantitative ratio of each component used at this time is the molar ratio of the titanium compound to the magnesium compound, which is 0. /~IO.

The ratio of the number of moles of aluminum compound to the sum of the number of moles of magnesium compound and the number of moles of titanium compound /-J-
Preferably, it is 0.

The reaction product b) is obtained as a precipitate by reacting an oxygen-containing organic compound of magnesium with a titanium halide compound at 50 DEG to 200 DEG C. in the presence or absence of an inert hydrocarbon solvent. There is no particular restriction on the ratio of the amounts used of both components at this time, but if the titanium halogen compound is too large, titanium will be wasted, and if it is too small, the polymerization activity will decrease, so the Ti/Mg (molar ratio) is usually o, i is selected within the range of 100.

Examples of organoaluminum compounds used as cocatalysts together with the transition metal compound components described above include dialkylaluminum chlorides such as diethylaluminum chloride, diisobutylaluminum chloride, and ethylmethylaluminum chloride, ethylaluminum-tusesquichloride, and isopropylaluminum sesquichloride. , alkylaluminium sesquichloride such as isopropylaluminium sesquichloride, alkylaluminum dichloride such as ethylaluminum dichloride, inch-1 methylaluminum dichloride, triethylaluminum, triisoprenylaluminum.

Trialkylaluminums such as ethyldiisopropylaluminum and trialkenylaluminums such as triisoprenylaluminum are mentioned, and organic aluminum compounds in which the number of carbon atoms in the hydrocarbon group bonded to aluminum is about 2 are usually used. However, if trialkyl aluminum is used in a hydrogenation system, it will be hydrogenated and it will be difficult to control the molecular weight, so it is not preferable to use it in a hydrogenation system.

Two or more of these organoaluminum compounds may be used in combination. The amount of the organoaluminum compound used is the atomic ratio of aluminum to the transition metal in the transition metal compound component of 0. /-2008- Preferably /-20.

The copolymerization reaction of ethylene or ethylene and other α-olefins with a non-conjugated diene is carried out in the presence of the above catalyst using aliphatic hydrocarbons such as hexane and heptane, aromatic hydrocarbons such as benzene, toluene and xylene, and cyclohexane. ,
The reaction is carried out in an inert hydrocarbon solvent such as an alicyclic hydrocarbon such as methylcyclohexane at a temperature of jθ to 100°C.

The non-conjugated diene is preferably a non-conjugated diene at both ends, /, Hiro-pentadiene, i, r-hexadiene, 7
．． 7-octadiene, 1. Tardecadiene, /, /
/-docadiene, comethyl-l, ≠-pentagene,
Komei Lou/2. t-hexadiene, 3-ethyl-/
, 7-octadiene, divinylbenzene, etc.

α-olefins other than ethylene include propylene,
Butene! , hexene-1% Hiroshi-methylpentene-/,
A-olefins having from 3 to 11 carbon atoms such as octene-7 are used.

In the method of the present invention, the polymerization reaction is carried out in two stages,
@The second stage polymerization reaction is carried out in the presence of the first stage polymerization product. The two-stage copolymerization reaction can be carried out by either a continuous polymerization method or a five-stage polymerization method. In the case of continuous polymerization, reactors are connected in parallel in λ groups, and the reaction mixture obtained by polymerization in the first reactor is introduced into the second reactor to continue polymerization. And if necessary, between the two reactors,
Install a flash tank that can purge most of the hydrogen. In the case of batch polymerization, reactions are carried out sequentially in seven reactors.

In the two-stage copolymerization reaction of the present invention, in either stage the viscosity average molecular weight is 100,000 to 10,000, and the diene content is 0.0/-10% by weight.

A polymer (Shu) having an α-olefin content of 10% by weight or less is produced, and in the other step a polymer (Shu) with a viscosity average molecular weight of 10,000 to 10,000 to 10,000 yen and a diene content and an α-olefin content of both Polymer (B) not larger than Al
It is necessary to produce the polymer (A) and the polymer (gradient) in a weight ratio of 3/7 to 7/3.

Here, the viscosity average molecular weight is determined by measuring the intrinsic viscosity in a tetralin solution at 130°C. ), the viscosity average molecular weight of the polymer (Shu) is expressed by the following formula, [η].-(/θθ[η]-W
B[η:]B)/WA (where [η]A indicates the limiting viscosity of the polymer (N), [η]B indicates the limiting viscosity of the polymer fB), and [η] indicates the limiting viscosity of the polymer (N). Indicates the intrinsic viscosity of the total polymer finally obtained in the one-stage polymerization reaction, h WA indicates the weight percent of the polymer (A) produced in the first-stage polymerization reaction, and wB indicates the total viscosity of the polymer (A) produced in the first-stage polymerization reaction. The viscosity average molecular weight can be calculated by finding [η]A from (indicates the weight percent of the polymer (B) produced in ).

In addition, the content of the diene compound is determined by the infrared absorption spectrum
It was determined from the absorption of θcrn', l1tyn-', etc.

The diene compound content in M combination (A) is 0.0/11
- When it is less than io weight %, it does not have a significant effect on the melting properties of the polyethylene produced, and on the other hand, when it exceeds io weight %, the rigidity decreases, which is undesirable.

When forming the polymer (N and fBl, it is also possible to copolymerize other α-olefins.
In Al, α-olefin content f/11d0.0
/-/0% by weight is preferred.

It is preferred that the diene content and α-olefin content Jl of the polymer TB) is also not greater than that of the polymer.

The polymer in the copolymer obtained by the method of the present invention (
If the content of A) is small, fish eyes may be formed, and if the content is too large, moldability will deteriorate.

The order of polymerization is to form one polymer (A), then to form a polymer (B).
1 may be produced, or the polymer (B) may be produced first and then the polymer (A) may be produced.

It is preferable that the polymer produced as described above is kneaded in advance. The polymer obtained by the present invention is easily homogenized, and is homogenized and pelletized using a continuous kneading extruder. The polymer obtained after cross-crossing has the advantage of having no fish eyes.

Next, the present invention will be explained in detail with reference to examples, but the present invention is not limited to the following examples which do not go beyond the gist of the invention.

In addition, in the following examples, physical property tests were performed on the obtained polymer material at 30 gm121, L, /D = , 27,
The weight was measured using a sample that was kneaded using a Dalmage screw extruder (≠Or, p, m, % temperature C1 = ltO°C, a2 = iro°C, D = 190°C and formed into pellets.

The extrusion amount as a measure of moldability (extrudability) was measured using a Gravender Co./D type single screw extruder (caliber/9./Fu I21.
L/D=2), compression ratio: 3 full flight screw,
The die is a circular die with a diameter of λOmfr and a clearance of O9, tWl), and the extrusion amount is measured at a die temperature of 200℃ and 5 rotations ljO rotations/min, and the extrusion amount is divided by the rotation speed (/30 rotations/min). The amount of extrusion molding per rotational speed was determined.

Fish eyes were visually determined from this cylindrical melt extrudate. ESOR was measured by the Bell Telephone method described in AS'l'MD-/l-3.

Melt index (abbreviated as M) is AIEtTMD-
/23rVc based on 190°C, 2. Measured under /l# load. The density was measured by JISK tVtO density gradient tube method.

The ballast effect was measured using a Shimadzu Kousakusho fissure flow tester, and the diameter/wn, L/D, 2, and the angle of liquid entry into the nozzle were 3.
Temperature/90℃ shear V − using 00 nozzle
) = (cross-sectional area of extruded object/cross-sectional area of nozzle) at 1000 sec' expressed as (α10
(abbreviated as 00). The smaller α1000, the smaller the balance effect (die swell).

Melt tension is 230℃, draft rate/, co! It was measured with

(The nozzle uses /ggXjm inflow angle + o"g') Examples/~6 Comparative example 1..2 (1) Catalyst adjustment (N magnesium ethoxide l/jf- and tree n-
Butoxymonochlorotitanium/j/l and n-butanol 3
71 and were mixed for t hours at 1H θ°C to homogenize. Then, the temperature was lowered to 10''C, and benzene was added to form a homogeneous solution.

Next, ethylaluminum sesquichloride was added dropwise at a predetermined temperature, and the mixture was stirred for an hour. A catalyst composition diagram was obtained by washing the generated precipitate with n-hexane. A portion of the obtained solid is dried into powder. This powder contains Mg/1. In terms of ON amount %, 10.1% of Ti was engaged by weight.

(B) Magnesium ethoxide 10f and titanium tetrachloride 70- were reacted at 730°C for 2 hours. After cooling n-
A catalyst component (B) was obtained by washing with hexane.

(2) Polymerization jt-A--) 3 of normal hexane was placed in a creve, and the amount shown in the table was charged with the above slurry excluding solids.

Prepare a predetermined amount of organoaluminum compounds shown in Table 7,
H [After raising the temperature to foot temperature, hydrogen was introduced.

15- Next, ethylene and optionally an α-olefin or a nonconjugated diene were supplied, and a polymerization reaction was carried out while supplying ethylene. The amount of polymerization reaction was determined based on the cumulative amount of ethylene supplied.

When the predetermined yield was obtained, ethylene was supplied, and the pressure was kept constant while supplying ethylene.

A constant temperature polymerization reaction was carried out.

The amount of polymerization reaction was determined based on the cumulative amount of ethylene supplied.

The table below shows the results of measuring the physical properties of the obtained polymer.
Indicates l/c.

16 one

Claims (3)

[Claims] (1) In a method for producing an unsaturated copolymer by copolymerizing ethylene, ethylene, and other a-olefins with a nonconjugated diene in the presence of a catalyst consisting of a transition metal compound component and an organoaluminum compound, the copolymerization The reaction is carried out in two stages, and in either stage, a polymer T having a viscosity average molecule *io to 100,000, a diene content of 0.01 to IO weight %, and an α-olefin content of 10 weight % or less is produced.
A) is produced, and in the other step, a polymer (B) having a viscosity average molecular weight of 10,000 to 10,000 and a diene content and an α-olefin content not larger than that of the polymer (A) is produced. A method for producing an unsaturated copolymer, characterized in that the amount of polymer (A) and polymer (copolymer) produced is from 3/7 to 7/3 in weight ratio. (2) The method according to claim 7, wherein the non-conjugated diene is a diene having double bonds at both ends. (3) The method according to claim 1, wherein the transition metal compound component is a solid component containing titanium, magnesium, and halogen.