JPH0153286B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing an olefin copolymer. More specifically, the present invention relates to a method for producing a copolymer of ethylene and α-olefins, or a multicomponent copolymer of ethylene, α-olefins, and a diene or polyene.

Conventionally, various catalysts for producing amorphous olefin copolymers have been proposed, but so-called Ziegler-type catalysts are particularly effective. It is generally known that a catalyst comprising an organoaluminium compound and a vanadium compound, particularly a trivalent to pentavalent vanadium compound soluble in an inert organic solvent, has excellent effects.

However, although many of such vanadium compound-containing catalyst systems exhibit extremely high activity at the initial stage of the polymerization reaction, the activity rapidly decreases in a relatively short period of time and the catalyst efficiency is also low.

Many polymerization activators have been proposed to improve this low catalyst efficiency, including alkyl esters of trichloroacetic acid and tribromoacetic acid (Japanese Patent Publication No. 15052/1983), perchlorocrotonic acid esters ( Halogen compounds such as Japanese Patent Publication No. 44-9390) and cellosolve esters of trichloroacetic acid or tribromoacetic acid (Japanese Unexamined Patent Publication No. 53-5288) are very effective, and the catalyst efficiency is dramatically improved.

However, if these polymerization activators are used, the ratio of the organoaluminum compound to the vanadium compound can be increased, or the ratio of the organoaluminum compound and the polymerization activity can be increased compared to a normal catalyst system consisting of an organoaluminum compound and a vanadium compound. A sufficiently large effect cannot be obtained unless the molar ratio of the curing agents is set to 2 or more. Moreover, if copolymerization is carried out using these polymerization activators, a polymer with a narrow molecular weight distribution measured by GPC will be produced.
(The breadth of the molecular weight distribution of a polymer is the Q value (w/
n). ) Ethylene and α-olefin or ethylene and α-
When producing a copolymer of olefin and polyene, it is important to develop a technology that freely controls the molecular weight distribution of the polymer in order to provide diversity in polymer quality and obtain a polymer with excellent physical properties and processability. . In particular, the cold roll properties, green strength, roll processability, extrusion processability, etc. of a polymer are physical properties that are closely related to the molecular weight distribution of the polymer.

The present inventors have arrived at the present invention as a result of studies on a method for producing a copolymer using the above-mentioned catalyst system. That is, the present invention deals with copolymerization of ethylene with α-olefins represented by the general formula CH ₂ =CHR (where R is a straight-chain alkyl group or a branched alkyl group having 1 to 6 carbon atoms), or non-copolymerization. In producing a ternary or multicomponent copolymer containing one or more linear or cyclic diene or polyene monomers having conjugated double bonds,
(a) Vanadium compound represented by VOX ₃ (X represents halogen), and (b) RaAlX _3-a
(However, a is 1≦a≦3, R is a hydrocarbon group having 1 to 20 carbon atoms, and X is a halogen.) or (a)
Vanadium compound, (b) organoaluminum compound,
and (c) a polymerization activator selected from the group consisting of methyl trichloroacetate, n-butyl perchlorocrotonate, and esters of trichloroacetic acid and cellosolve. After premixing and aging, the three components are added to the polymerization tank. Furthermore, we have added (b) an organoaluminum compound, or (b) an organoaluminum compound and (c) a polymerization activator to the polymerization tank to produce ethylene and α-olefin with a wide molecular weight distribution. This invention relates to a method for producing an olefin copolymer consisting of ethylene, α-olefin, and diene or polyene.

The organoaluminum compound (b) used in the present invention (hereinafter referred to as "organoaluminum compound") is:
It is represented by the general formula RaAlX _3-a (where R is a hydrocarbon group having 1 to 20 carbon atoms, X is a halogen or alkoxy group, and a is 1≦a≦3), and is a dialkyl aluminum monohalide, Alkyl aluminum sesquihalides and alkyl aluminum dihalides are effective, and these may be used alone or in combination. Specific examples of these compounds include diethylaluminum chloride, diethylaluminum bromide, diisobutylaluminum chloride, diisobutylaluminum bromide, ethylaluminum sesquichloride, isobutylaluminum sesquichloride, ethylaluminum dichloride, ethylaluminum dibromide, isobutylaluminum dichloride, Examples include isobutylaluminum dibromide.

(a) Vanadium compound (hereinafter referred to as "vanadium compound") used in the present invention is VOX ₃ (however,
X represents halogen. ) is a pentavalent vanadium compound represented by the following: vanadium oxytrichloride is an optimal specific example thereof.

The polymerization activator (c) used in the present invention (hereinafter referred to as "polymerization activator") is selected from the group consisting of methyl trichloroacetate, n-butyl perchlorocrotonate, and esters of trichloroacetic acid and cellosolve. It is a compound that

In order to effectively carry out the present invention, it is necessary to pre-mix the organoaluminum compound and the vanadium compound, or the three components of the organoaluminum compound, the vanadium compound, and the polymerization activator. The mixing ratio of the compound and the vanadium compound and the selection of the premixing temperature and premixing time are important factors.

That is, when performing premixing, the molar ratio of the organoaluminum compound and vanadium compound (hereinafter expressed as Al/V) is 0.5 to 20, more preferably 1.
It may be carried out in steps 5 to 5. There is no particular restriction on the proportion of the polymerization activator used in the premixing, and it can be used in any proportion within the range of the amount of polymerization activator added to the polymerization tank (described later).

The temperature during premixing is in the range of -100°C to +50°C, more preferably in the range of -80°C to 0°C.

In addition, the mixing time for pre-mixing ranges from a few seconds to 60 minutes.
Good results are obtained by feeding the polymerization tank preferably after 5 seconds to 10 minutes.

When using a polymerization activator, good results cannot be obtained unless the total amount of the organoaluminum compound used in the pre-mixing and the organoaluminum compound added afterwards is at least twice the mole of the polymerization activator. do not have. Further, the organoaluminum compound used for premixing and the organoaluminum compound used for post-addition may be the same or different types of organoaluminum compounds.

In carrying out the present invention, α-olefins used for copolymerization with ethylene have the general formula CH ₂
=CHR (R is a straight-chain alkyl group or a branched alkyl group having 1 to 6 carbon atoms), and specific examples include propylene, 1-butene, 1-pentene, 1-hexene, and 4-methyl- Examples include 1-pentene, but propylene is particularly preferred.

In addition, as polyene components used for copolymerization, 1,4-hexadiene, 1,6-octadiene, 6-methyl-1,5-heptadiene, 1,9
-Octadecadiene, cycloheptanediene-
1,4, dicyclopentadiene, 5-methylene-
2-norbornene, 5-isopropenyl-2-norbornene, 2-methyl-2,5-norbornadiene, 5-ethylidene-2-norbornene, 5-
Examples include isopropylidene-2-norbornene, cyclooctadiene-1,5, and methyltetrahydroindene, but 1,4-hexadiene,
Zinclopentadiene and 5-ethylidene-2-norbornene are particularly preferred.

To carry out the polymerization reaction using the catalyst components according to the invention, commonly used hydrocarbon or halogenated hydrocarbon solvents, such as hexane, heptane, kerosene, cyclohexane, benzene, chloroform, trichloroethylene, tetrachloroethane, It is carried out by solution polymerization using perchlorethylene or the like. Suspension polymerization can also be carried out using a solvent that does not dissolve the copolymer, such as 1,2-dichloroethane or methylene chloride. Furthermore, polymerization can also be carried out in the presence of only monomers and catalyst components without using a solvent.

The polymerization temperature can be varied over a wide range, but is usually -
It is carried out at a temperature of 50°C to 100°C, particularly preferably a range of -30°C to 80°C.

Polymerization is carried out under atmospheric pressure or under pressure, and 1
It is preferable to carry out at ~50Kg/ ^cm2 , especially 1~30Kg/cm2.
Preference is given to between Kg/ ^cm2 .

In carrying out the present invention, the Al/V molar ratio in the polymerization reaction may be as high as 1000/1, but it is usually preferably between 5/1 and 100/1. When a polymerization activator is used, it is used in an amount of 0.005 to 0.5 mol, preferably 0.01 to 0.5 mol, per 1 mol of the organoaluminum compound.
In addition, the ratio of the polymerization activator to the vanadium compound is
It is preferably between 0.1 mol and 100 mol, particularly preferably between 1 mol and 30 mol, per mol of the vanadium compound.

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.

The content of the present invention will be specifically explained below using examples, but the present invention is not limited thereto in any way.

Example 1 A stirrer, a thermometer,
Attach a dropping funnel and a reflux condenser to reduce the pressure and then replace with nitrogen. Dry normal hexane 1 is placed in this flask, kept at a constant temperature of 30°C, and a mixed gas of 40 mol% ethylene and 60 mol% propylene is flowed through it at a rate of 10 N/min and hydrogen 1 N/min for 30 minutes to saturate it. . Then, a catalyst prepared by premixing 0.4 mmol of ethylaluminum sesquichloride and 0.2 mmol of vanadyl trichloride (same as VOCl ₃ oxyvanadium trichloride) at -10°C for 30 seconds, and an additional 3.6 mmol of ethylaluminum sesquichloride and 5- Ethylidene-2-norbornene 8
mmol into the separable flask to start ethylene/propylene/5-ethylidene-2-norbornene ternary copolymerization. Further, a mixed gas of ethylene and propylene was flowed for 30 minutes while stirring to carry out polymerization. Next, 30 ml of methanol was added to stop the reaction, and after thorough washing with methanol, the reaction mixture was poured into a large amount of methanol to precipitate a copolymer. Dry the precipitate under reduced pressure
8.6 g of white amorphous solid copolymer was obtained. The intrinsic viscosity of this polymer is 1.82 dl/g (70 dl/g in xylene).
°C), the propylene content of the copolymer determined from the infrared absorption spectrum is 33.8 mol%, and the iodine value is
It was 8.3. The thus obtained polymer had a very wide molecular weight distribution with a Q value of 8.8 (Figure 1) and had excellent roll processability.

Comparative Example 1 Comparative Example 1 is an example corresponding to Example 1.
It was carried out in the same way. However, instead of the premixed catalyst and the additionally added ethylaluminum sesquichloride, 4.0 mmol of ethylaluminum sesquichloride and 0.2 mmol of vanadyl trichloride were each directly charged into the separable flask for polymerization.
In this way, 8.8 g of a white amorphous solid copolymer was obtained.
The obtained copolymer had an intrinsic viscosity of 1.73, a propylene content of 36.8, and an iodine value of 8.1.

In addition, its molecular weight distribution is narrow with a Q value of 3.2 (Fig.
1) Poor roll workability.

Example 2 The same procedure as in Example 1 was carried out. However, in the pre-mixing, 0.4 mmol of ethylaluminum sesquichloride,
Using 0.2 mmol of vanadyl trichloride, additionally added 3.6 mmol each of ethylaluminum sesquichloride and methyl trichloroacetate as a polymerization activator.
mmol, 0.8 mmol was used, but no hydrogen was used as a molecular weight control agent. Further, 15 mmol of dicyclopentadiene was used as the diene component. In this way, 23.1 g of a white amorphous solid copolymer was obtained. The intrinsic viscosity of the copolymer is 1.54 dl/g,
The propylene content was 37.7 mol% and the iodine number was 7.8. The molecular weight distribution of the polymer thus obtained was 4.7 in terms of Q value, and it had strong green strength and excellent roll processability.

Comparative Example 2 The same procedure as in Example 2 was carried out. However, the copolymerization reaction was carried out by directly charging 4.0 mmol of ethylaluminum sesquichloride, 0.8 mmol of ethyl trichloroacetate, and 0.2 mmol of vanadyl trichloride into the separable flask without using the premixed catalyst components. In this way, 26.8 g of a white amorphous solid was obtained. The obtained copolymer had an intrinsic viscosity of 1.44, a propylene content of 37.6, an iodine value of 7.6, a narrow Q value of 2.8, and poor roll processability.

Example 3 The same procedure as in Example 1 was carried out. However, as a premixed catalyst, ethylaluminum sesquichloride 0.8
−30 mmol and 0.2 mmol of vanadyl trichloride
Using a catalyst premixed for 30 seconds at °C, 3.2 mmol of diethylaluminum chloride was used as the additional organoaluminium, and 15 mmol of 5-ethylidene-2-norbornene was used as the diene component. In this way, 9.1 g of a white amorphous solid copolymer was obtained.
This polymer had an intrinsic viscosity of 1.74 dl/g, a propylene content of 42.1 mol%, and an iodine number of 8.1.
The molecular weight distribution of the copolymer thus obtained is expressed by the Q value.
9.3 and has excellent roll processability.

Example 4 The same procedure as Example 2 was carried out. However, 0.4 ethylaluminum sesquichloride is used as a premixed catalyst.
mmol, n-butyl perchlorocrotonate
0.4 mmol, vanadyl trichloride 0.2 mmol -30
℃ for 10 seconds before use. An additional 2.6 mmol of ethylaluminum sesquichloride was also used.

In addition, as a diene component, 5-ethylidene-2-
15 mmol of norbornene was used. In this way, 23.3 g of a white amorphous solid copolymer was obtained. The copolymer had an intrinsic viscosity of 1.69 g/dl, a propylene content of 38.5 mol%, and an iodine number of 6.7. The molecular weight distribution of the polymer was wide with a Q value of 6.1, and it exhibited excellent roll processability. (Figure 2) Comparative Example 3 The same procedure as in Example 4 was carried out. However, without using a premixed catalyst, 3.0 mmol of ethylaluminum sesquichloride, 0.8 mmol of n-butyl perchlorocrotonate, and 0.2 mmol of vanadyl trichloride were each directly charged into a separable flask to conduct polymerization, resulting in a white amorphous solid. 26.8 g of polymer was obtained. This copolymer has an intrinsic viscosity of 1.12 g/dl, a propylene content of 42 mol%, and an iodine number of 6.7.
The molecular weight distribution is narrow with a Q value of 2.3 (Figure 2), and roll processability is poor.

[Brief explanation of drawings]

The figure shows the molecular weight distribution of the polymer measured with Shimadzu GPC-1A. The solid line is the molecular weight distribution of the polymer obtained in the present invention, and the broken line is the molecular weight distribution of the polymer obtained in the comparative example. Figure 1 shows Example 1 and Comparative Example 1, and Figure 2 shows Example 4 and Comparative Example 3. FIG. 3 is a flowchart to help understand 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)

[Scope of Claims] 1. Copolymerization of ethylene and α-olefins represented by the general formula CH ₂ =CHR (where R is a straight-chain alkyl group or a branched alkyl group having 1 to 6 carbon atoms); Alternatively, in producing a ternary or multicomponent copolymer containing one or more linear or cyclic diene or polyene monomers having non-conjugated double bonds, (a) VOX ₃ (where X represents a halogen) ), and (b) RaAlX _3-a (where a is 1≦a≦3, R
represents a hydrocarbon group having 1 to 20 carbon atoms, and X represents a halogen. ) or the above (a) vanadium compound, the above (b)
After premixing and aging the three components, an organoaluminum compound and (c) a polymerization activator selected from the group consisting of methyl trichloroacetate, n-butyl perchlorocrotonate, and esters of trichloroacetic acid and cellosolve, the polymerization is carried out. Add the above (b) organoaluminum compound or the above
Olefin consisting of ethylene and α-olefin, or ethylene, α-olefin, and diene or polyene, which has a wide molecular weight distribution and is characterized by adding (b) an organoaluminum compound and the above-mentioned (c) polymerization activator to the polymerization tank. Method for producing copolymer. 2 The molar ratio of the organoaluminum compound (b) and the vanadium compound (a) during pre-mixing aging is Al/
2. The method of claim 1, wherein V=0.5-20. 3 The molar ratio of the organoaluminum compound (b) and the vanadium compound (a) during pre-mixing aging is Al/
2. The method of claim 1, wherein V=1-5. 4. The method according to claim 1, wherein the temperature during pre-mixing and ripening is -100°C to +50°C. 5. The method according to claim 1, wherein the temperature during pre-mixing and ripening is -80°C to 0°C. 6. The method according to claim 1, wherein the total amount of the (b) organoaluminum compound in the premix aging and the (b) organoaluminum compound in the post-addition is at least twice the mole of the (c) polymerization activator. Method. 7. The method according to claim 1, wherein the organoaluminum compound (b) is diethylaluminum chloride, ethylaluminum dichloride, diisobutylaluminum chloride, isobutylaluminum dichloride, ethylaluminum sesquichloride, or isobutylaluminum sesquichloride. 8. The method according to claim 1, wherein the vanadium compound (a) is vanadium oxytrichloride. 9. The method according to claim 1, wherein the (b) organoaluminum compound used during pre-mixing and ripening and the additionally added (b) organoaluminum compound are of the same or different types. Method.