JPS6017369B2 - Polymerization method of α-olefin - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for polymerizing Q-olefin using a novel catalyst.

More specifically, it relates to a method for producing a polyolefin with a narrow molecular weight distribution and excellent moldability by polymerizing Q-olefin by solution polymerization using a novel catalyst consisting of a special organomagnesium compound and a titanium compound. It is something.

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 reaction temperature of solution polymerization is high, there can be a large temperature difference between the internal temperature and the jacket, resulting in good heat removal efficiency. This becomes more advantageous as the polymerization temperature increases. (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.

■ Polyethylene is generally used in the form of pellets, and polyethylene produced by suspension polymerization and gas phase polymerization is in the form of powder, and extra energy is required to form it into pellets using an extruder.

In solution polymerization, the solvent can be evaporated using the heat of polymerization, and molten polyethylene can be introduced into the extruder, so energy can be used effectively. In order to take advantage of this advantage, it is desirable that the polymerization temperature be higher. On the other hand, a problem with solution polymerization is that increasing the solution temperature or increasing the molecular weight of polyethylene increases the solution viscosity and reduces production efficiency.

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 shark soot 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. Furthermore, it is difficult to remove catalyst residue. Therefore, there is a need for a catalyst with high catalytic efficiency at high temperatures, which leaves less catalyst residue in polyethylene and eliminates 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 15,000, and the performance is insufficient to omit the catalyst residue removal step in solution polymerization. . An olefin solution polymerization catalyst using an organomagnesium fin body, an aluminum halide, hydrogen chloride, or a secondary or tertiary alkyl halide and a titanium compound is disclosed.

(Tsubaki Kosho 47-11372, Tsubaki Sekikai 50th 14 x Hosoiri Hakama Sekisho 51-144397). Although these catalysts have higher catalytic efficiencies compared to conventional catalysts, they are sufficient to omit the catalyst removal step, especially in high temperature polymerizations. As a result of investigating solution polymerization catalysts, the present inventors found that a reaction product of a special organomagnesium compound and a silicon halide compound,
By combining an organoaluminum compound with a catalyst component made by contacting a halogen-free titanium compound, the catalyst efficiency is extremely high, and the catalyst is more than 15 pi○, especially 180q
The present inventors have found and developed a catalyst that exhibits little reduction in catalytic efficiency even at temperatures above 100 ℃, is stable and can be stored for a long period of time, and has developed the present invention.

That is, the present invention provides (i) general formula MQMg8RIPR
and X1r 10r+s=mQ+28, 0≦(
r+s)/(Q+8)≦1, m is the valence of M, and R1 and R2 are the number of carbon atoms 1, which may be the same or different.
~20 hydrocarbon groups, X1 and X2 are the same or different groups, hydrogen atoms OR3, OSiR4R5R8, NR7R8,
SR9 represents a group, R3, R7, R8, RQ represent a hydrocarbon group having 1 to 20 carbon atoms, and R4, R5, R6 represent a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms)
A reaction product of an organomagnesium compound soluble in a hydrocarbon solvent and (ii) a halogenated silicon compound represented by
(iii) A reaction product obtained by contacting a halogen-free titanium compound [A] and an organoaluminum compound [B]
This is a method for polymerizing Q-olefins, which is characterized in that the polymerization is carried out by solution polymerization in a range of 120 to 350 qo under one-stage or multi-stage polymerization conditions.

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/gTi 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 k9/gTi can be achieved even at temperatures of 180 pm or more. A third feature of the invention is that it provides a polymer with a very narrow molecular weight distribution.

As shown in the examples below, it is possible to produce a polymer with a narrow molecular weight distribution suitable for injection molding. The fourth feature of the present invention is that the catalyst can be stored for a long period of time.

As shown in Example 21, no significant decrease in catalyst efficiency was observed even after one month of catalyst synthesis. This means that a balanced catalyst can be used for a long period of time, which facilitates long-term stable operation of polymerization, and represents a great industrial advantage. Both the general formula MQMgPR1pR and X1rX used in the catalyst of the present invention (in the formula, M, R1, R
2, X1, X2, Q, 8, p, q, r, s have the above-mentioned meanings) The organomagnesium compound (i) will be explained.

Although (i) is shown as an organomagnesium compound, it includes all R2Mg and their combinations with other metal compounds. In the above formula, M can be a metal element belonging to Groups 1 to M of the periodic table, such as lithium, sodium, potassium, beryllium, calcium, strontium, barium, zinc, boron,
Examples include aluminum, but lithium, beryllium, boron, aluminum, and zinc are particularly preferred because they facilitate the production of hydrocarbon solvent-soluble organomagnesium fins. More preferably, aluminum is used. The magnesium ratio 3/Q to the metal atom M can be set arbitrarily including dialkylmagnesium derivatives where Q=0, but preferably 0<B/Q≦50, particularly 0.5≦8/Q≦10.
Hydrocarbon solvent soluble organomagnesium fin bodies are preferred. The hydrocarbon group represented by RI to R9 is a hard alkyl group, cycloalkyl group, or allyl group having 1 to 2 carbon atoms, such as methyl, ethyl, propyl, butyl, amyl, hexyl, tesyl, cyclohexyl, Examples include phenyl, benzyl groups, etc., especially R1, R2
is preferably an alkyl group, and there is no preclude that R4, R5, and R6 are hydrogen atoms. On the other hand, when Q=0, in order to obtain a hydrocarbon solvent soluble organomagnesium compound, R
1. The hydrocarbon group of R2 is limited. For example, the first case is when RI and/or R2 is a secondary or tertiary alkyl group having 3 or more carbon atoms, and the second case is when RI is an alkyl group having 2 to 6 carbon atoms and R2 is a carbon atom number is an alkyl group of 4 or more, and the difference in the number of carbon atoms between RI and R2 is 2 or more. Specifically, (sec-C
4 days 9) 2Mg, (sec-C4 Mr.) Mg (n-C 4 days 9), (iso-C 3 days 7) Mg (n-C4 ratio), (C
2&) Mg (n-C4 ratio), etc. are used. Symbol q, 8
, p, q, r, s relational expression p q + r + s = mQ 128
indicates the stoichiometry between the metal valence and the substituent, and for the sum of metal atoms in the preferred range of 0≦(r+s)/(Q+3)≦10, the sum of XI and Indicates that:

In order to increase the stability of the catalyst component [A], it is necessary to add XI to the substituent.
Alternatively, it is recommended that X2 be contained, that is, (r+s)>0. These organomagnesium compounds have the general formula RIM cough Q, R chamber M (RI has the above meaning, Q
is a halogen atom) and the compound represented by the general formula M
R2m, MR2〆lbX2c, MQ. X1bX2c(M
, R2, X1, X2, Q, m have the above-mentioned meanings, a,
b, C are a + b + c = m) in an inert hydrocarbon such as hexane, heptane, octane, cyclohexane, benzene, toluene, etc.
It is synthesized by reacting at 50° C. and, if necessary, further reacting it with an alcohol, siloxane, amine, imine, thiol, or dithio compound.

Furthermore, organic magnesium compounds include MgX12, RIM
gXI and M old 2m, MR2m-, day, or RIMgX
1. R12M8 and R2J X2m-n or RIM
gX1, R is also Mg and XlamX2m-. (In the formula, M
, R1, R2, X1, X2, m have the above-mentioned meanings, and X
1, X2 is a halogen, a is a number from ○ to m). In general, organomagnesium compounds are immovable in inert hydrocarbon solvents,
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 (sec-C4 days)2Mg, (
C2Q)Mg (n-C4day9) and the like 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, the halogenated silicon compound side will be explained.

A halogenated silicon compound is a silicon compound having at least one halogen-silicon bond. Preferred are chlorides soluble in hydrocarbon solvents, such as SIC14, SIC3・CI3, (CH3)2SI
C12, C2, 5SIC13, etc. are used. Particularly preferably, as SIC1a, a hydrochlorosilane represented by R04-(a+b) (R0 is a hydrocarbon group having 1 to 20 carbon atoms, and a and b are numbers of 1 or more) is used. for example,
SiHC13, CH3SiH・CI2, C ratio SiH2C
I, (CH3)2SiH・CI, CH2:CHS
iHC12, C2 & Si・Japan・CI2, C2 Nittei SiQ
C1, (C ratio) 2SjHC1, n-C3 day 7SiHC1
2nd prize is mentioned. Halogen-free titanium compound (li
i) will be explained.

As titanium compounds, Ti(OCH3)4, Ti(O
C2 day 5) 4, Ti (0n-C3 day 7) 4, Ti (0i
1 C3 day 7) 4, Ti (0n-C4) 4, Ti (0i
-C4 day 9) 4, Ti (en-C4 day 9) 4, Ti (0n
-C 6 days, 3) 4, Ti (OC 8 days, 7) 4, T
i (OC, 8th, 7th) 4, Ti (OC, 6th day 4)
CH3)4, Ti[OCH(CH3)2]2(QC
5 days, ) 2, Ti (OC3 days, ) 2 [OCH (CH3)
COOH]2 etc. are used. Preferably, titanate ester is used, and more preferably tetraptoxytitanium and tetraisopropoxytitanium are used. (i)
, tii, (iii) can be carried out using an inert reaction solvent, such as aliphatic hydrocarbons such as hexane, heptane, and octane, aromatic hydrocarbons such as benzene and toluene, and alicyclic carbonizations such as cyclohexane and methylcyclohexane. It can be carried out in hydrogen or a mixture thereof. In terms of catalyst performance, aliphatic hydrocarbon solvents are preferably used. Various methods can be considered for the reaction order of (..., qi}, Oil), but in order to exhibit highly active catalytic performance, it is necessary to avoid contact between (i) and Gi) in advance. More specifically, a solid component is generated by the reaction between (1) and Gi), and the solid component is effectively (ii)
By contacting i), the surprising effects of the invention are achieved. The reaction between (i) and Gi} can be carried out by a simultaneous addition method in which two components are simultaneously introduced into the reaction zone and reacted, or one component is charged into the reaction zone in advance and the remaining component is introduced and reacted. Any of the so-called forward (reverse) addition methods, in which the

The reaction temperature is not particularly limited, but is preferably 0 in view of reaction progress.
to 150 pm, particularly preferably at 20 to 100°C. 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 mol to 1 mol of component (i).
A range of 20 hols is recommended.

A collective component is generated by the reaction between (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, it is necessary to It is preferable to introduce (iii) into this reaction solution to further proceed with the reaction.
Mg/Ti SI0 preferably 10≦Mg/TiSI0
Ti concentration in the reaction solution was 4 mol/
It is desirable to use 1 or less. The reaction temperature is not particularly limited, but is preferably carried out in a range of 50 to 150 qo in view of reaction progress. When the catalyst component [A] of the present invention is combined with the organoaluminum compound [B], it becomes an excellent catalyst for polymerization of q-olefin.

As organoaluminum compounds, AI (C2 day 5) 3, Yama (C3 day,) 3, AI (C4 day 9)
3, AI (C5 days,.) 3, AI (C6 days, 3) 3, Yama (C8 days, 7) 3, AI (C, oH illusion) 3, etc. trialkyl aluminum, AI (C2 days, 5) 2CI , mountain (C2
&) CI2, AI(i-C4 ratio)2CI, AI(C
2 days 5) Aluminum halide such as 2Br, mountain (C2
&) 2 (0C 2 days 5), N (iC 4 days 9) 2 (OC 4 days 9), etc. Alkoxy aluminum, AI (C 2 days 5) 2
・(06iH・C horse・C2 day 5), N(i-C4 ordinary)・
Siloxyalkylaluminums such as (OSi(C)2.1.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.

In addition, the ratio of both components to be combined is as follows: Ti in component [A]
is defined by the molar ratio of M in component [A] and N in component [B], preferably (M+AI)/Ti is 3/1 to 1.
000/1, more preferably a range of 5/1 to 500/1. The catalyst of the present invention is suitable for the polymerization of ethylene, but includes propylene, butene-1, isobutene, hexene-1, 4-methylbentene-1, octene-1,
It is also possible to perform copolymerization with ethylene in the presence of Q-olefin such as decene-1 in an amount of 10 mol % or less relative to ethylene, and by homopolymerization and copolymerization, a density of 0.
It is possible to produce polyethylene in the range 975-0.910.

The polymerization is preferably carried out in a temperature range of 120 to 35°C, more preferably 150 to 3200°C, by a solution polymerization method.

As the polymerization solvent, aliphatic hydrocarbons such as hexane, heptane, and octane, aromatic hydrocarbons such as benzene, toluene, and 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, ethylene was added to 0.
．． 1Mpa to 40Mpa, preferably Impa to 28M
Polymerization can be carried out by introducing the ethylene at a partial pressure of 1.5 p.m. and mixing with a rope sludge machine, etc., to ensure good contact between ethylene and the catalyst.

Polymerization may be carried out in one stage using one reaction zone, or
Alternatively, it is also possible to perform so-called multistage 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 ester titanate as a third component and adjusting the density. 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, and according to ASTM D-1238, the temperature was 190,000 yen.
, measured under a load of 2.16k9. F
R means the quotient obtained by dividing the value measured at a temperature of 19 mm and a load of 21.6 mm by the skin, and is one of the measures of molecular weight distribution.
The lower the value, the narrower the molecular weight distribution. The catalyst efficiency is expressed as the amount of Ti polymer produced per night k9. Example 1 (1) Synthesis of hydrocarbon solvent soluble organomagnesium compound Five minutes of magnesium powder was added to a 20-liter flask that had been purged with nitrogen.

2 m of a mixture of 20.8 ml of n-butyl chloride and 6 m of hebutane was introduced into the flask.

Heat the flask and apply reflux to start the reaction.
Once the mixture was refluxed for 2 hours, the remaining n-butyl chloride was added dropwise to the mixture, and the mixture was left to stand for another 1 hour. AI for this
2 liters of hebutane containing 12 hmol of C12 (0n - C4 day 9) was added and the reaction was carried out at 70 qo for 2 hours to obtain an organomagnesium compound solution. As a result of analysis, the composition of this body is Mg7-5 (n-C44),6
-9·(0n-C44)o-9, and the organometallic concentration was 0.88 hol/1. In addition, AIC12 (0m
-C4day9) was synthesized by reacting aluminum powder, NC13, and core 4days and 90days in hebutane at a molar ratio of 1:2:3.

(0) A 25-hour vessel equipped with a synthesis dropping funnel for catalyst component [A] and a water reflux condenser.
Oxygen and moisture inside the 1 flask were removed by nitrogen substitution, and 0.1 mol of 1 trichlorosilane was added under nitrogen atmosphere.
2 mL of hebutane solution and 3 mL of hebutane were added, and the temperature was raised to 70 qC.

Next, the above component (i)2. 1 liter of blood and 2 ml of hebutane were weighed into a dropping funnel. The mixture was added dropwise over a period of 1 hour at a temperature of 7 mm, and the reaction was further allowed to proceed for 1 hour at this temperature.

The reaction solution became a white suspension. This white suspension contains 27% of hebutane and 10.6% of tetrabutoxytitanium.
．． 7 Kite' was introduced and the reaction was carried out at 7 P0 for 1 hour. (
m) Catalyst component [A] synthesized by polymerization of ethylene (0) 2.0 I and 0.02 hmol of trioctyl aluminum were dehydrated and degassed together with 0.6 kerosene and 1 autoclave with the inside vacuum degassed. I put it in.

Next, hydrogen mol, da' autoclave 18
Polymerization was carried out for 30 minutes while keeping the total pressure constant by maintaining 0 CO, pressurizing ethylene at a pressure of 3.0 MPa, and replenishing ethylene.

As a result, a polymer of 37.6 hours was obtained. Catalyst efficiency is 1
158[9/Shio Ti, MI was 7.2, FR32, and density was 0.971. Examples 2 to 12 According to the method of Example 1, the components (i) shown in Table 1,
Catalyst component [A] was synthesized using qi) and tetraptoxytitanium as the component.

Polymerization was carried out under the same conditions as in Example 1, except that this catalyst component [A], catalyst component [B] in the table, and catalyst component (■) in the table were used, and the results in the table were obtained. . Table I Examples 13-20 According to the method of Example 1, AIM & (n-C4 Tow)8
(0n1C4day9)32. Enmmol and HSiC131
．． 8 hmol was reacted under the conditions shown in Table 0, and then component qii) was allowed to act on this reaction solution under the reaction conditions shown in Table m,
Catalyst component [A] was synthesized.

Using this catalyst component [A]2' and 0.04 mmol of trioctylaluminum, ethylene polymerization was carried out under the conditions shown in Table D, and the results shown in the table were obtained. Example 21 The catalyst component [A] synthesized in Example 1 was heated under nitrogen atmosphere.
After allowing it to stand for several months, similar polymerization was carried out.

As a result, 35.2 hours of polyethylene was obtained. The catalyst efficiency was 1048k9/taTi, MI was 9.6, and FR33, showing the same performance as Example 1. Table Example 22-25 AIM & (n-C Rainbow.3) 8.2 (OS.・Japanese・CH3
・C6th, 3).

．． 82. Enemy hmol and HSi・CH3・CI2 3. Catalyst component [A] was synthesized under the same conditions as in Example 1 except that hmol was used. This was introduced into a 1-quart autoclave whose interior was vacuum degassed, along with 0.6 hmol of methylcyclohexane, which was obtained by dehydrating and degassing 0.09 hmol of triethylaluminum. Next, 7 mmol of hydrogen
and shown in Table m. - Add olefin, 160 qo
The temperature was raised to 2.3 Vpa, and ethylene was pressurized at a pressure of 2.3 Vpa.
By replenishing ethylene, while maintaining the total pressure,
Polymerization was carried out for 0 minutes and the results shown in the table were obtained. Table m Example 26 The method of Example 1 was carried out using 2.0 of the catalyst component [A] synthesized in Example 1 and 0.03 hmol of trioctyl aluminum under the conditions of ethylene pressure of 2 Mpa, hydrogen 3 hmol, and temperature of 140 qo. Therefore, ethylene 1.8 hol
Polymerization was carried out.

Claims (1)

[Claims] 1 (i) General formula MαMgβR^1_pR^2_qX
^1_rX^2_s (where M is from Group I to II of the periodic table)
Group I metal atom, β is a number greater than or equal to 1, α, p, q, r, s
is 0 or a number greater than 0, p+q+r+s=mα+2β
, 0≦(r+s)/(α+β)≦1, where m is the valence of M, and R^1 and R^2 are hydrocarbon groups having 1 to 20 carbon atoms, which may be the same or different; X^1 and X^2 are the same or different groups, hydrogen atom, OR^3, OSiR^4
Represents the groups R^5R^6, NR^7R^8, and SR^9, where R^3, R^7, R^8, and R^9 have a carbon atom number of 1 to
20 hydrocarbon groups, R^4, R^5, and R^6 represent a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms) and an organomagnesium compound soluble in a hydrocarbon solvent represented by ) to the reactant of the silicon halide compound, (i
ii) Using a reaction product [A] formed by contacting a halogen-free titanium compound and an organoaluminum compound [B], polymerization is carried out by solution polymerization under one-stage or multi-stage polymerization conditions in the range of 120 to 350°C. α-
Olefin polymerization method. 2. The method for polymerizing α-olefins according to claim 1, wherein M in the organomagnesium compound (i) is a lithium, beryllium, boron, aluminum or zinc atom. 3. The method for polymerizing α-olefins according to claim 1 or 2, wherein β/α is 0.5 to 10 in the organomagnesium compound (i). 4. The method for polymerizing an α-olefin according to claim 1, wherein α=0 in the organomagnesium compound (i). 5 (i) In the organomagnesium compound, 0<(r
+s)/(α+β)≦1, the method for polymerizing α-olefin according to any one of claims 1 to 4. 6 (ii) The silicon halide compound has the general formula SiCl
A silicon compound represented by aHbR^0_4-(a+b) (wherein R^0 is a hydrocarbon group having 1 to 20 carbon atoms, and a and b are numbers of 1 or more) The method for polymerizing α-olefin according to any one of Item 5. 7
The method for polymerizing α-olefin according to any one of claims 1 to 6, wherein the halogen-free titanium compound (iii) is a titanate ester. 8. The α-olefin polymerization method according to claim 7, wherein the halogen-free titanium compound (iii) is tetrabutoxytitanium or tetraisopropoxytitanium. 9. The reaction between (i) and (ii) is carried out at a temperature of 0 to 150°C with 0.1 to 100 m of component (ii) per 1 mol of component (i).
A method for polymerizing α-olefin according to any one of claims 1 to 8, which is carried out within the range of ol. 10 In contacting the reactants (i) and (ii) with (iii), the temperature is 50 to 150°C and the Mg/Ti molar ratio is 3.
The method for polymerizing α-olefin according to any one of claims 1 to 9, which is carried out in the range of 1 to 500. 11 In catalyst components [A] and [B], (M+A
11. The method for polymerizing α-olefin according to any one of claims 1 to 10, wherein the molar ratio of l)/Ti is in the range of 3/1 to 1000/1. 12 Polymerization temperature 150-320°C, ethylene partial pressure 1.0
12. The polymerization method according to any one of claims 1 to 11, wherein ethylene is polymerized at a pressure of ~25 megapascals (MPa). 13 Using catalyst components [A] and [B], ethylene and 3 carbon atoms of 100 mol% or less relative to ethylene
The polymerization method according to any one of claims 1 to 12, which carries out the copolymerization of the above α-olefins.