JPS6019923B2 - Method for manufacturing polyolefin - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a process for polymerizing olefins using a novel catalyst.

More specifically, the present invention provides a method for polymerizing olefins in which olefins are polymerized or copolymerized by a solution polymerization method using a novel catalyst consisting of a special organomagnesium compound, a specific halide, and a titanium or/and vanadium compound. This is related to. Solution polymerization is already known as a suitable method for producing polyethylene.

The advantages of this solution polymerization include the following. '
1' ethylene polymerization is an exothermic reaction, and heat removal is a major problem in the process.

Since the heat removal efficiency increases as the temperature difference between the inside of the polymerization vessel and the inside of the cooling jacket increases, solution polymerization with a high reaction temperature is advantageous in this respect. (2) The degree of polymerization of ethylene, that is, the molecular weight of polyethylene, can be controlled relatively accurately by changing the reaction temperature, and molecular weight control can be achieved by using a small amount of hydrogen.

{31 Since there is a correlation between the molecular weight of polyethylene and the viscosity of the reaction solution, it is possible to estimate the molecular weight of polyethylene by measuring the viscosity of the solution in the reactor and take prompt action.

{4' Polyethylene products are generally used commercially in the form of pellets.

Since polyethylene obtained by suspension polymerization or gas polymerization is in powder form, it is necessary to melt-form it into pellets using an extruder. On the other hand, in solution polymerization, the solvent can be evaporated using the heat of polymerization, and molten polyethylene can be introduced into the extruder, so extra steps and melting energy can be omitted. Therefore, it is extremely advantageous in terms of effective use of energy. To take advantage of this,
Higher polymerization temperatures are desirable. On the other hand, a problem with solution polymerization is that increasing the concentration of the solution or increasing the molecular weight of polyethylene increases the viscosity of the solution, making it difficult to implement on a factory scale.

To solve this problem, it is necessary to raise the polymerization temperature and lower the solution viscosity. However, when the polymerization temperature is raised, the catalyst efficiency decreases and a large amount of catalyst residue remains in the polyethylene. This results in coloring of the polyethylene and deterioration of the product after molding. Also, removal of catalyst residue is difficult. Therefore, there is a need for a catalyst that has high catalytic efficiency at high temperatures and leaves little catalyst residue in the polyethylene, eliminating the need for a removal step. In the suspension polymerization method, many Ziegler type catalysts with high catalytic efficiency are known.

However, the catalyst efficiency of these catalysts generally decreases as the polymerization temperature is raised, and the decrease is particularly significant at temperatures above 150° C., and the performance is insufficient for eliminating the catalyst residue removal step in solution polymerization. An olefin solution polymerization catalyst using an organomagnesium rust body, aluminum halide, hydrogen chloride or a secondary or tertiary alkyl halide, and a titanium compound has been disclosed (Japanese Patent Publication No. 47-11372Z, Special Publication No. 5
0-14 Ball Powder No. 3, Special Seki No. 51-144397).

Although these catalysts have higher catalytic efficiency than conventional catalysts, their catalytic efficiency at high temperatures is still insufficient. The present inventors investigated solution polymerization catalysts, and found that an organometallic compound was added to the catalyst component, which is made by contacting a reaction product of a special organomagnesium compound and a halide with a titanium compound and/or a vanadium compound. By combining these, the catalytic efficiency is extremely high.
The present inventors have discovered and developed a catalyst that exhibits little reduction in catalytic efficiency even at temperatures above 0.000 m, is stable and can be stored for a long period of time, and has now completed the present invention.

That is, the present invention provides (l) general formula MQ MgR1pR2qX1rX2s (wherein M is a metal atom of Group 1 to Group m of the periodic table, and Q. p, q, r, and s are 0 or a number larger than 0; , p+q+r+s=mQ+2, 0≦
(r+s)/(Q11)<2.0, m is M
valence, RI is a hydrocarbon group having 1 to 20 carbon atoms, R
2 is a secondary or tertiary alkyl group having 3 to 20 carbon atoms, X1 and X2 are the same or different groups and represent a hydrogen atom or a negative group containing oxygen, nitrogen or sulfur atom) an organomagnesium compound soluble in a hydrogen solvent;
Y is a halogen atom, and a is a number of 0 and 1. is in the range of 3 to 500, and Ti
Using the catalyst component [A] and the organometallic compound [B], which are brought into contact with each other at a concentration of 2 hol/1 or less in an inert reaction medium of 10 V, the solution state is determined at a temperature of 120q0 to 320q0 This is an olefin polymerization method in which polymerization is carried out in one stage or in multiple stages.

The features of the present invention will be explained below. The first feature of the present invention is high catalyst efficiency.

As is clear from the examples described later, the catalyst efficiency is 500k.
g/g (Ti 10 V) or more can be achieved, and the catalyst residue removal step can be omitted. The second feature of the present invention is that it is stable even at high temperatures.

As is clear from the Examples described later, a catalyst efficiency of 500 kg/g (Ti+V) can be achieved even at 180 qo or more. The third feature of the present invention is that a polymer with a narrow molecular weight distribution and high molecular weight and high rigidity that can be molded by injection molding can be obtained.

The fourth feature of the present invention is that polymers with a wide molecular weight distribution and suitable for extrusion molding can be produced by performing polymerization using a multistage reaction zone in which conditions such as the temperature and hydrogen concentration of the reaction zone are changed. be.

General formula MQMgR1p used in the synthesis of the catalyst of the present invention
R2qX1rX2s (where M, R1, R2, X1,
2, Q, p, q, r, s have the above-mentioned meanings) The organomagnesium compound (i) will be explained. Although (i) is shown in the form of an organomagnesium compound, R2
It includes all complexes of Mg and these with other metal compounds. In the above formula, M is Group 1 of the periodic table ~
Metallic elements belonging to the Melon group can be used, such as lithium, sodium, potassium, beryllium, calcium,
Examples include strontium, barium, zinc, boric acid, aluminum, etc., but lithium, beryllium, boron, aluminum, and zinc are particularly preferred because they facilitate the production of hydrocarbon solvent-soluble organomagnesium bodies. More preferably, aluminum is used. The ratio Q of metal atoms M to magnesium atoms can be set arbitrarily including dialkylmagnesium derivatives where Q=0, but preferably OSQSI. 0, especially 0 QSO. The hydrocarbon solvent-soluble organomagnesium key body of No. 5 is preferred. The hydrocarbon group represented by RI is an alkyl group, cycloalkyl group, or allyl group having 1 to 20 carbon atoms, such as methyl, ethyl, propyl, butyl, amyl, hexyl, decyl, cyclohexyl, phenyl, benzyl. groups, among which alkyl groups are particularly preferred. The alkyl group represented by R2 is a secondary to tertiary group having 3 to 20 carbon atoms.
alkyl groups of the same class, for example, isopropyl, se
c-butyl, t-butyl, sec-ami/shi, t-butyl
Lower alkyl groups such as t-amyl, SeC-hexyl, and Sec-octyl are preferred. These secondary and tertiary alkyl groups are extremely important in terms of the constituent elements of the present invention, and the effects of the present invention can only be exhibited by using organomagnesium compounds containing such groups. X1 and X2 represent a hydrogen atom or a negative group containing oxygen, nitrogen, or sulfur atom, preferably formulas ○R4, OSiR5R6R7,
NR8R9, SRI0, (wherein R4 to R13 are hydrocarbon groups having 1 to 20 carbon atoms, R5 to R9, R12
may be a hydrogen atom).

Particularly preferably alkoxy (OR4) or siloxy (
OSiR5R6R7). Symbol Q, p, q, r,
The relational expression p+q+r+s=mQ+2 for s indicates the stoichiometry between the valence of the metal atom and the substituent, and the preferable range of OS(r+s)/(Q+1)<2.0 is based on the sum of the metal atoms. Indicates that the sum of XI and X2 is greater than or equal to 0 and less than 2.0.

In order to obtain high catalytic efficiency at high temperatures, X1 and X2 are important, and 0<(r1s)/(Q11)≦1.5, preferably 0.1S(r+s)/(Q+1). ≦1.3 is recommended. In general, organomagnesium compounds are immovable in inert hydrocarbon solvents, and organomagnesium compounds where Q>0 are soluble.

In the present invention, it is necessary to use a soluble organomagnesium compound. Also, certain organomagnesium compounds, such as (secC4 ratio) 2Mg, (rt-C4 day 9) 2Mg, (isoC3 day 7) Mg (n
-C4 ratio), (secC4&)Mg(n-C44), etc. have Q=0, but are soluble in hydrocarbon solvents, and such compounds can of course be used in the present invention to give preferable results.
Next, as a compound of the general formula R3aCX4~ (in the formula, R3, x, a have the above-mentioned meanings), 4C. Geninated carbon, monohydrohalogenated carbon, and monoalkylhalogenated carbon are used. Examples of preferred compounds include carbon tetrachloride, chloroform, 1,1,1-trichloroethane, 1,1,1-trichloropropane, and mixtures thereof. Particularly preferred compounds are carbon tetrachloride and chloroform. Titanium compounds and/or vanadium compounds include titanium tetrachloride, titanium tetrabromide, titanium tetrachloride, ethoxytitanium trichloride, and titanium tetrachloride.

Poxytitanium trichloride, butoxytitanium trichloride, dipropoxytitanium dichloride, dibutoxytitanium dichloride, tripropoxytitanium chloride, tributoxytitanium chloride, tetrapropoxytitanium, tetrabutoxytitanium, vanadium tetrachloride, vanadyl trichloride,
Titanium and vanadium halides, oxyhalides, alkoxyhalides, alkoxide compounds, and oxyalkoxide compounds, such as butoxyvanadyl dichloride, dibutoxyvanadyl chloride, and triptoxyvanadyl, may be used alone or in mixtures. Preferably it is a titanium or vanadium compound containing at least one chlorine atom. (i), (ii), (iii)
The reaction is carried out in an inert reaction solvent such as aliphatic hydrocarbons such as hexane, heptane, octane, aromatic hydrocarbons such as benzene, toluene, alicyclic hydrocarbons such as cyclohexane, methylcyclohexane, or mixtures thereof. It can be done with In terms of catalyst performance, aliphatic hydrocarbon solvents are preferably used. (i), (ii),
Various methods can be considered for the reaction order of the side, but in order to exhibit highly active catalytic performance, the reaction order of (i) and (ii) is recommended.
i] must be avoided from coming into contact with it. More specifically, the surprising effects of the present invention are achieved by producing a solid component through the reaction of (i) and (ii), and by effectively bringing (iii) into contact with the surface of this solid component. (i)
The reaction of (ii) 1 can be carried out either by a simultaneous addition method in which two components are introduced into the reaction zone at the same time, or in which one component is charged into the reaction zone in advance and then the remaining one component is introduced into the reaction zone.
Any of the so-called forward (reverse) addition methods in which the reaction is carried out is possible.

There is no particular restriction on the reaction temperature, but from the viewpoint of reaction progress it is preferably -
It is carried out at 50 to 15 q○, particularly preferably from 0 to 100 q○. There is no particular restriction on the reaction ratio of the two components, but preferably 0.01 to 10 mol of component (ii), particularly preferably 0.1 to 2 mol of component (i).
A range of enemies is recommended.

A solid component is produced by the reaction of (i) and (ii), but
This can be isolated by filtration or washed by decantation, and then subjected to the reaction with (iii), but in order to simplify the reaction operation, after the reaction of (i) and (ii) is completed, It is preferable to introduce "ii)" into this reaction solution to further advance the reaction. In order to obtain the effects of the present invention, the amount of titanium and/or vanadium compound (iii) used (Mg/(Ti+V)) and the concentration in the reaction mixture are important. The amount of (iii) used is the molar ratio 3≦Mg(
Ti+V)≦500 preferably 5≦Mg/(Ti10V)
≦20, more preferably 10≦Mg/(Ti+V)≦
100, and the concentration of Ti+V in the reaction solution was 2.
It is necessary to do this at rol/1 or less, especially for one dish hm
The range of oi/1 to 0.01 mmol/1 is preferable. There is no particular restriction on the reaction temperature, but from the viewpoint of the reaction progress, it is preferably 15.
It is carried out in the range of 0 to 15yo, more preferably 0 to 9yo. The catalyst component [A] of the present invention becomes an excellent catalyst for Q-olefin polymerization when combined with the organometallic compound [B].

As the compound [B], preferably an organoaluminum compound is used. As an organoaluminum compound, A
I (C2 day 5) 3, N (C3 day 7) 3, AI (C4 day 9)
) 3, AI (public day, .) 3, AI (C6 day, 3) 3, N
(C8 days, 7) 3, AI (C, oH milk) trialkyl aluminum such as 3, AI (C2 days 5) 2 CI, N (C2
) CI2, AI( i -C4 is)2CI, AI(C
2 days 5) Aluminum halides such as 2Br, N(C2
day 5) 2 (OC2 day 5), AI (i-C4 day 9) 2 (O
Alkoxy aluminum such as C4 day 9), AI (C2 day 5) 2 (OSiH C is C2 day 5), N (i-C4
Siloxyalkylaluminums such as ).(OSi(C4)2.i-C4day9)2 and mixtures thereof are used.

Catalyst components [A] and [B] may be added into the polymerization system under polymerization conditions, or may be combined in advance prior to polymerization.

Also, the ratio of both components to be combined is T in the [A] component.
It is defined by the molar ratio of i+V and [B] component, and [B]/(T
i + V) is 3/1 to 1000′1, preferably 5/1 to
A range of 500/1 is recommended. The catalyst of the present invention is suitable for the polymerization of ethylene, but also propylene, butene-1,
Isobutene, hexene-1,4-methylbentene-1,
It is also possible to copolymerize ethylene with a Q-olefin such as octene-1 or decene-1 or a polyene such as butadiene or isoprene, and it is particularly preferable to use the Q-olefin in an amount less than 1 mol per mol of ethylene.

Density 0.975-0.9 by homopolymerization and copolymerization
It is possible to produce a range of 10 polyethylenes. Polymerization is preferably carried out at 120-320°C, more preferably at 15°C.
The solution polymerization method is carried out at a temperature range of 0 to 300°C.

As the polymerization solvent, aliphatic hydrocarbons such as hexane, heptane, and octane, aromatic hydrocarbons such as benzene, toluene/xylene, and alicyclic hydrocarbons such as cyclohexane and methylcyclohexane are used. The catalyst was introduced into the reactor together with the polymerization solvent, and under an inert atmosphere, 0.1
Mpa~4NMpa, preferably Impa~29Mpa
Polymerization can be carried out by introducing such a partial pressure that the ethylene is introduced at a partial pressure of The polymerization may be carried out in a single-stage polymerization using one reaction zone, or it is also possible to carry out a so-called multi-stage polymerization using a plurality of reaction zones.

Although this catalyst yields polyethylene with a narrow molecular weight distribution in one stage polymerization, it is also possible to produce polyethylene with a wide molecular weight distribution through multistage polymerization. Furthermore, in order to control the molecular weight, it is also possible to change the temperature of the reactor or add hydrogen or an organic compound that is likely to cause chain transfer. Furthermore, it is also possible to carry out the polymerization by adding a titanate ester as a third component and adjusting the density in combination. Examples of the present invention are shown below, but the present invention is not limited to these examples in any way. In these examples, MI stands for melt index, which was measured according to ASTM D-1238 under the conditions of a temperature of 19 mm and a load of 2.16 kg. FR has a temperature of 19 pm and a load of 21.6 kg.
It is a measure of molecular weight distribution, and the lower the value, the narrower the molecular weight distribution. Catalytic efficiency is expressed in kg of polymer produced per Ti+VIg. Example 1 (1) Synthesis of catalyst component [A] Capacity 250 equipped with dropping funnel and water-cooled reflux cooler
Oxygen and moisture inside the flask were removed by nitrogen substitution, and 0.1 mol/1 chloroform was added in a nitrogen atmosphere.
20 parts of a butane solution and 30 parts of hebutane were added and the temperature was raised to 70°C.

Next, AIo, . Mg(n-C44)shio(sec-C
4th day 3) Weigh 30' of hebutane containing 32.1 mmol of Shio (On-C4 mother) into a dropping funnel, and add 7000
The solution was dripped in a concentrated manner over a period of 2 hours. As a result, the reaction solution became a white suspension. 20 volumes of hebutane containing 57 mg of titanium tetrachloride were introduced into this white suspension, and the mixture was heated to 70°C.
The reaction was carried out for 2 hours. (b) 0.6 octane obtained by dehydrating and degassing catalyst component [A] 5' synthesized in ethylene polymerization (1) and 0.02 hmol of trioctyl aluminum.
The container was placed in a 1-quart autoclave with the inside vacuum degassed.

Next, after charging hydrogen side hmol, autoclave 1
Maintain 90 qo and ethylene at 4. (2) Polymerization was carried out for 20 minutes by increasing the pressure at a pressure of Mpa and keeping the total pressure constant by replenishing ethylene. As a result, approximately 5 polymers were obtained. Catalyst efficiency is 750k9 nogTi, MI is 6.9
, FR was 2, and the density was 0.969. Examples 2 to 8 (1) Synthesis of catalyst component [A] According to the method of Example 1, components (i) and (ii) were reacted using the components and conditions shown in Table 1, and then,
The component sides were brought into contact to synthesize catalyst component [A].

(0) Polymerization of ethylene The catalyst component [A]5 synthesized as described above and the catalyst component [
B] was subjected to ethylene polymerization according to the method of Example 1 using the ingredients and conditions shown in Table 2, and the results shown in Table 2 were obtained.

Table 1 Table 2 Example 9 Using 2.0' of catalyst component [A] synthesized in Example 1 and 0.05 hmol of trioctyl aluminum, ethylene pressure was 4. According to the method of Example 1, 1. enemy hol
Polymerization was carried out.

Next, 8 liters of hydrogen was introduced and the internal temperature was raised to 18 liters, and then 2 liters of ethylene was added again. Introduce the plate at a pressure of Mpa,
Polymerization of 0.82 hol of ethylene was carried out. As a result, M
A polymer of 13.2 and FR95 was obtained. Examples 10-1
4 AIM5Mg (C2 days 5),. 5 (sec-C4 ratio) [
0 (n - C4 ratio) 2] Small 32.0 ribs, HCC133
．． 5 skin ol and TIC140.15 pig ol and VOC1
Catalyst component [A] was synthesized according to the method of Example 1, except that 30.05 pig ol was used.

Add 4 ml of this and 30.16 ribs of AI (i-C4 day 9)
with 0.6 ml of dehydrated and degassed methylcyclohexane,
The mixture was introduced into an autoclave whose interior was vacuum degassed. Next, 1 liter of hydrogen and the olefins shown in Table 3 were added, and the temperature was raised to the temperature shown in Table 3. 3. Ethylene. ■Mp
Pressure is increased to a partial pressure of a, and the total pressure is maintained by replenishing ethylene.) Ethylene 1. Polymerization was carried out until the shoe OL was polymerized, and the results shown in Table 3 were obtained. Table 3

Claims (1)

[Claims] 1 (i) General formula MαMgR^1_pR^2_qX^1
_____r /(
α+1)<2.0, m is the valence of M, R^
1 is a hydrocarbon group having 1 to 20 carbon atoms, R^2 is a secondary or tertiary alkyl group having 3 to 20 carbon atoms, X^1,
X^2 is the same or different group and represents a hydrogen atom or a negative group containing oxygen, nitrogen or sulfur atom); -_a (wherein R^3 is hydrogen or a hydrocarbon group having 1 to 10 carbon atoms, Y is a halogen atom, and a represents a number from 0 to 1), (iii ) A titanium compound and/or a vanadium compound is used in a range in which the molar Mg/(Ti+V) of Mg and Ti+V is in the range of 3 to 500, and Ti
Using catalyst component [A] and organometallic compound [B] which are brought into contact with each other under conditions where the concentration of +V in an inert reaction medium is 2 mol/l or less, at a temperature of 120°C to 320°C in the state of a solution. A method for polymerizing olefins in which polymerization is carried out under single-stage or multi-stage conditions. 2 In the organomagnesium compound, M is lithium,
The method for polymerizing an olefin according to claim 1, wherein the olefin is a beryllium, boron, aluminum, or zinc atom. 3. The method for polymerizing olefin according to claim 2, wherein M in the organomagnesium compound is an aluminum atom. 4. The method for polymerizing olefin according to claim 1, wherein α in the organomagnesium compound satisfies 0≦α≦1. 5 In organomagnesium compounds, X^1 or X^2 is OR^4, OSiR^5R^6R^7, NR^
8R^9, SR^1^0, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (In the formula, R^4 to R^1^3 are hydrocarbon groups having 1 to 20 carbon atoms, and R^5 ~R^9,R
The method for polymerizing olefins according to claim 1, wherein ^1^2 may be a hydrogen atom. 6 In organomagnesium compounds, 0.1≦(r+
s)/(α+1)≦1.3, the method for polymerizing olefins according to claim 1. 7. The compound of (ii) is
The method for polymerizing olefin according to claim 1, wherein chloroform and carbon tetrachloride are used. 8. The method for polymerizing olefins according to claim 1, wherein the compound (iii) is a titanium or/and vanadium compound containing at least one chlorine atom. 9
The method for polymerizing olefins according to claim 1, wherein the reaction of (i) and (ii) is carried out at a temperature of -50 to 150°C. 10. The method for polymerizing olefins according to claim 1, wherein the reaction is carried out at a molar ratio of (i) and (ii) in the range of 1:0.1 to 1:20. 11 Add (iii) to the reactants of (i) and (ii)
2. The method for polymerizing olefins according to claim 1, wherein the contacting is carried out at a temperature of 0 to 95°C. 12. The method for polymerizing olefin according to claim 1 or 11, wherein Mg/(Ti+V) is 10 to 10.0. 13 When bringing (iii) into contact with the reactants of (i) and (ii), the concentration of Ti+V is 100 mmol to 0.01 mm.
Claim 1 or 1 under the condition of ol/l
The method for polymerizing olefins according to item 1 or item 12. 14. The method for polymerizing olefins according to claim 1, wherein [B] is an organoaluminum compound. 15 The molar ratio of Ti + V in [A] and [B] is [B]/(
The method for polymerizing olefin according to claim 1, wherein Ti+V) is used in the range of 3/1 to 1000/1. 16. The method for polymerizing olefins according to claim 1, wherein the polymerization of ethylene is carried out at 150 to 300°C and an ethylene partial pressure of 1.0 to 25 megapascals (Mpa). 17. The method for polymerizing olefins according to claim 1, wherein [A] and [B] are used to copolymerize ethylene and an α-olefin or polyene other than ethylene. 18. The method for polymerizing olefin according to claim 17, in which α-olefin having 3 to 20 carbon atoms is used in an amount of 5 mol or less per 1 mol of ethylene.