JPS61108610A - Production of polyolefin - Google Patents

Abstract

PURPOSE:To obtain polymer stably without forming deposition on the inside wall, etc., of a reactor, by polymerizing an olefin in the presence of a supported solid catalyst component comprising a specified transition metal compound and a reaction product between a trialkylaluminum and water. CONSTITUTION:A transition metal compound of the formula (wherein M is Ti or Zr, R is a C1-C6 alkyl, X is a halogen and m is 0-2), e.g., biscyclopentadienyltitanium dichloride) and a reaction product between a trialkylaluminum (e.g., trimethylaluminum) and water are supported on an inorganic oxide carrier (e.g., silica or alumina). an olefin (e.g., ethylene or propylene) is (co) polymerized in the presence of the obtained solid catalyst component and the formed polymer particles. IN this way, a polyolefin can be obtained without deposition of polymer particles on the inside wall, agitator, etc., of a polymerization vessel.

Description

DETAILED DESCRIPTION OF THE INVENTION 1 The present invention relates to a process for producing polyolefins using a novel catalyst system with substantial formation of polymer particles. More specifically, the present invention relates to a method for stably producing polyolefin while substantially forming polymer particles using a carrier-supported catalyst produced by a novel method.

picture! 3 Using a homogeneous catalyst obtained from a transition metal complex and an organoaluminum compound, an olefin polymer (
It is already known that copolymers) can be obtained;
It is widely used in research on the reaction mechanism of Chiguchi catalysts.

However, since its polymerization activity is extremely low, it is rarely used in the industrial production of polyolefins. However, it has recently been known that extremely high polymerization activity can be obtained by using a soluble catalyst consisting of bis(cyclopentadiene dichloride) zirconium dichloride and methylalumoxane (Japanese Unexamined Patent Publication No. 18309/1983). ,
It is attracting attention.

In addition to having very high polymerizability per transition metal compound, this catalyst system is extremely sensitive to hydrogen, making it suitable for producing low molecular weight polyethylene (so-called wax), and also for producing ethylene and propylene. However, this catalyst system can be used in the so-called "slurry polymerization" or When used in "gas phase polymerization," various problems occur such as the formation of coarse polymers, a decrease in polymer bulk density, polymer reaction and adhesion to walls, and the resulting decrease in heat transfer coefficient, making stable operation difficult. be.

ζ "-2 occupancy The present invention is a catalyst which improves the above-mentioned drawbacks, and when used in slurry polymerization or gas phase polymerization of olefins, it has high activity, does not cause polymer adhesion, and can stably produce polyolefins. The aim is to provide a system.

. As a result of intensive studies to achieve the above objectives, (A) General formula (cyclopentagenyl) 2 MRm
X2-m (m = O ~ 2, M = 〒1 or Zr
, R is an alkyl group having 1 to 6 carbon atoms, or a halogen atom) and (B) a reaction product of trialkylaluminium and water are supported on (C) an inorganic oxide carrier. The above object is achieved by not additionally feeding an activator compound as a co-catalyst to the polymerization reactor when producing polyolefins in the presence of a solid catalyst component obtained by substantially forming polymer particles. The present invention was achieved based on this discovery.

According to the method of the present invention, both a specific transition metal compound and an activator compound are supported on a porous carrier and supplied to a reactor.
It was unexpected that polymer adhesion during slurry polymerization or gas phase polymerization could be prevented and stable operation would be possible. 1. Furthermore, in polymerization using a Ziegler catalyst, it is well known that an activator compound (mainly an organoaluminum compound) is supplied to the polymerization reactor, and JP-A-54-1430G3 also describes It is a preferred embodiment to feed an activator compound to the reactor. Therefore, it is completely unexpected and surprising from the prior art that the effects of the present invention are achieved by a method in which no activator compound is supplied to the reactor as in the present invention.

The transition metal compound used in the present invention has the general formula (
cyclopentagenyl) 2 MR'm 0M represented by X2-m is a transition metal such as titanium or zirconium, R' is an alkyl group having 1 to 8 carbon atoms, X is a halogen atom, and 1m is θ ~2 numbers. Representative examples of suitable ones include biscyclopentadienyl zirconium dichlorite and biscyclopentadienyl titanium dichloride. In the present invention, a reaction product of trialkylaluminium and water is used as one of the catalyst components. However, specific examples of trialkylaluminium include trimethylfluminium, triethylaluminum, tri-1-propylaluminum, triisobutylaluminum, or mixtures thereof. Particularly favorable results are achieved when using trinotylaluminum. The reaction between trialkylaluminium and water is a condensation reaction, and the resulting product varies depending on the molar ratio of both components in one reaction and reaction conditions, but has the general formula R2 (AM-0) AlR2 (where R2 is carbon Number 1
~6 alkyl groups, n being a g number of 1 or more. ) or a mixture thereof. The above reaction involves gradually adding a predetermined amount of water to trialkylaluminum dissolved in an inert hydrocarbon solvent such as toluene.
This can be easily done by slightly heating if necessary, but it can also be done using crystallization water of copper sulfate, pentahydrate zinc sulfate, heptahydrate, etc.

The amount of water used is usually 0.1 to 1.5 molar ratio to trialkylaluminum, preferably 0.
．． The molar ratio is 5 to 1.2. Outside this range, the catalytic activity decreases rapidly. The inorganic oxide support used in the present invention is an oxide of a metal of group 1Ia, ma, IXa, and IXb of the periodic table, Specific examples include silica, alumina, silica alumina, magnesia, and titania. Although the properties of these oxides vary depending on their type and manufacturing method, the carrier preferably used in the present invention has a surface area of torn' /g or more, an average pore diameter of 50 A or more, and a particle size of 100 lum or less. . In addition, in order to use these carriers for the purpose of the present invention, it is preferable that the amount of adsorbed water and hydroxyl groups on the surface be as small as possible, and for this purpose, it is necessary to perform a firing treatment at a high temperature. The firing temperature is preferably 500 to 800°C; below 500°C, the hydroxyl groups on the surface cannot be sufficiently reduced, and above 800°C, sintering occurs and pores are destroyed, which is undesirable. Particularly favorable results can be obtained when using silica or alumina calcined at 500-800°C.

When supporting the transition metal compound (A) and the reaction product CB of trialkylaluminium and water on the inorganic oxide carrier, these image components may be supported at the same time, and after supporting one, the other may be supported. Components may be supported. In addition, the supporting ratio of one component is 3 moles of the transition metal compound to 3
It is preferable to use 0 mol or more (A mole/M≧30), and if it is less than this, sufficient activity cannot be obtained.

The above picture component can be supported on an inorganic oxide carrier by impregnation, by dissolving the picture component (or one of the components) in an inert solvent, and then mixing the carrier with this solution. The supporting temperature is generally 100°C or less, and 0 to 40°C.
The solid catalyst component thus obtained, preferably at a temperature of 0.degree. C., is washed several times with an inert solvent and used as a slurry or after drying and powdered.

The polymerization carried out substantially while forming polymer particles according to the present invention is so-called slurry polymerization or gas phase polymerization. Examples of solvents used in slurry polymerization include:
Butane, isobutane, pentane.

Inert hydrocarbons such as hexane, cyclohexane, toluene, etc. alone or in mixtures. In addition, the 0 polymerization temperature at which α-olefin can be used as a solvent is:
Generally it is -1θ℃ to 150℃, and practically 0
The temperature is 1 to 100°C. Gas-phase polymerization is carried out in a gas-phase state substantially free of solvent, and a known reactor such as a fluidized bed stirring tank can be used.6 The polymerization temperature is usually 0 to 150'C.
and preferably 20 to 100°C.

In Ziegler-catalyzed polymerization, it is common to carry out polymerization by supplying both a transition metal compound and a liquid activator compound to a polymerization reactor. Besides the trialkylaluminium and water reactants, an additional activator compound is fed to the polymerization reactor. The activator compound is a compound known as an activator for so-called Ziegler polymerization, such as an organoaluminum compound, an organomagnesium compound, an organozinc compound, or the like.

The polyolefin in the present invention includes polyethylene, a copolymer of ethylene and other α-olefins, and a homopolymer of α-olefin. It is particularly exhibited in the production of copolymers. Typical examples of α-olefins used include propylene, butene-1, hexene-1,4-methylpentene-
1 is given.

The present invention will now be explained in more detail with reference to Examples.

Death,, s Example 8
MFIJ) is based on JIS K-8758,
Measurement was carried out at a temperature of 230'C and a load of 2.18 kg, and the ethylene content CE in the copolymer was measured by infrared absorption spectroscopy. In addition, the melting point is D manufactured by PerkinElmer Co.
Measurement was performed using an SC type scanning differential thermal analyzer.

Example 1 Trialkylaluminum compound, r: Bow in a 300 m Q Mitsuro flask purged with nitrogen.
n of toluene and 80 mmou of trimethylaluminum are added, and 30 mmou of water is added dropwise at -30°C. After the addition, the temperature was gradually increased and stirring was continued at 40°C for 10 hours to complete the reaction and obtain a reaction product.

In a 300-meter Mitsuro flask purged with nitrogen, a toluene solution of biscyclopentadienylzirconium dichloride (0.02 mo/stand) was mixed with a reaction product of 50 ffi, trimethylaluminum, and water, 5111 emal.
added. Then, the firing process is done with s o o ”c.
Add 5g of 5i02 (Fuji Davison #952) and continue stirring for 5 hours.
A solid catalyst component was obtained by washing with toluene several times. In 1 g of solid catalyst component, Z r 9 mg, A
It contained 140+ wg.

L 2nd 1st 3rd party stainless steel autoclave with 2f of imbutane
L. 2 g of the above solid catalyst component was added, and the internal temperature was raised to 70°C. Next, hydrogen was added at gauge pressure to 3 kg/Crn'.
In addition, ethylene is further pressurized to bring the partial pressure of ethyl/ton to 1.
Approaching was carried out for 1 hour while maintaining the temperature at 0 kg/am'. Polymerization was then terminated by discharging the contained gas to the outside of the system.

As a result, 175g of white powdery polymer was obtained.
Note that no polymer was observed to adhere to the inside of the autoclave.

When the molecular weight of this polymer was measured by GPC, it was found that Q
w = 8000<'atta.

Example 2 Ethylene Propylene lr 2g of the solid catalyst component obtained in Example 1 was placed in a 32 stainless steel autoclave purged with nitrogen, and then propylene? 00g was added, and the internal temperature was raised to 30°C. Then, ethylene was injected under pressure to bring the ethylene concentration to 10 mol%.
(relative to propylene) while supplying the
Polymerization was continued for 1 hour. Then, the supply of ethylene was stopped and the content gas was discharged to the outside of the system to terminate the polymerization. As a result, 182 g of granular polymer was obtained. Moreover, there was no polybu attached to the inside of the autoclave. The obtained one coalescence has MFL=1.3, CE=6
It was a random copolymer with a melting point of 8% and a melting point of 45°C.Example 3 Trialkylaluminium and nitrogen-substituted 3
0011 cup of copper sulfate pentahydrate in a Mitsuro flask
Add 0mmo sentence and suspend in toluene 100+J1. Next, add 300 imo of trimethylaluminum to 30
℃ and continue the reaction at that temperature for 48 hours. Then,
The reaction product was filtered through a glass filter to obtain a solution of the reaction product. When toluene was removed by distillation, 8.2 g of white crystals were obtained.

A solid catalyst component was obtained in the same manner as in Example 1, except that the reaction product of trimethylaluminum and water obtained by the above method was used. Z r per gram of solid catalyst component
It contained 155 mg of 9.2+of Al.

Five j here! Polymerization of ethylene was carried out in the same manner as in Example 1, except that 1 g of the solid catalyst component obtained above was used. As a result, there was no polymer adhesion in the autoclave.
283g of white powdery polymer was obtained. Q by GPC
w = 5800.

Example 4 A solid catalyst component was obtained in the same manner as in Example 3, except that biscyclopentadienyl titanium dichlorite was used instead of biscyclopentadienyl zirconium dichloride. Each gram of this solid catalyst component contained 4.8 rag of Ti and 180 mg of A.

Ethylene Propylene - Copolymerization of ethylene and propylene was carried out in the same manner as in Example 2, except that 2 g of the solid catalyst component obtained above was used. As a result, no polymer adhered to the autoclave, and 126 g of colored granular polymer was obtained. The obtained polymer had MF I =0.8, CE =
It was a random copolymer with a melting point of 70% and a melting point of 5Q°C.

Example 5 Ethylene Boo 7-1 The solid catalyst component obtained in Example 3 was placed in a stainless steel autoclave with nitrogen exchange.

Two volumes of isobutane were added, and the internal temperature was raised to 70°C. Next, 1190 g of butene was charged, and ethylene was then pressurized until the partial pressure reached 5 kg/cm'. Polymerization was carried out for 1 hour while supplying ethylene to maintain the pressure. One polymerization was then terminated by discharging the contained gas to the outside of the system. As a result, there was no polymer adhesion at all in the autoclave, and one white powdery polymer was left in the autoclave.
95g was obtained. This polymer had an MFI of 1.5 and a density of 21 g/cc of OJ.

Example 6 A solid catalyst component was obtained in exactly the same manner as in Example 3, except that biscyclopentadienylzirconium dimethyl was used instead of biscyclopentadienylzirconium dichloride. Each gram of this solid catalyst component contained 12.3 mg of Zr and 172 mg of All.

Ethylene Propylene 1 Copolymerization of ethylene and propylene was carried out in exactly the same manner as in Example 2, except that 2 g of the solid catalyst component obtained above was used. As a result, no polymer adhered to the autoclave, and 223 g of white granular polymer was obtained. This polymer had MF I =0.5, CE =8.
It was a random copolymer with a melting point of 6% and a melting point of 47°C.

Comparative example 1 ball jkoy'/L) do L gold In Example 1, instead of the solid catalyst component.

Biscyclopentagenyl zirconium dichloride 0
．． Example 1 except that 2+gmo and the reaction product of trimethylaluminum and water 1011IIO were used.
Polymerization of ethylene was carried out in the same manner.

As a result, most of the produced polymer adhered firmly to the inner wall of the autoclave and the stirrer, and the heat transfer coefficient decreased significantly, making temperature control difficult and making stable operation impossible.

Comparative Example 2 Same as Example 2, except that ethylene propylene was added to the autoclave in Example 2, and 2 mmol of the reaction product of trimethylaluminum and water obtained in Example 1 was added as an additional activator compound. Copolymerization of ethylene and propylene was carried out. As a result, the powdered polymer was 78. I got it, but
The polymer was firmly attached to the inner wall of the autoclave and the stirrer. This deposit was dissolved and removed with xylene, reprecipitated in methanol, dried, and weighed to find that it was 23 g.

Comparative Example 3 Ethylene Propylene, 1 Copolymerization of ethylene and propylene was carried out in the same manner as in Comparative Example 2, except that at a ratio of 412, triethylaluminum was used instead of the reaction product of trimethylaluminum and water.

As a result, 85 g of powdered polymer was obtained, but adhesion of the polymer was observed on the inner wall of the autoclave and the stirrer.The amount of adhesion recovered was 178.

Comparative Example 4 A toluene solution of biscyclopentadienyl zirconium dichloride (0.02 ml/ml) was added to a 300km Mitsuro flask purged with solid nitrogen, and then 5102 ml was calcined at 800°C.
(Fuji Davison Co., #952) 5 g was added. 5
After continuing to stir for a period of time, the mixture was washed several times with toluene to obtain a solid catalyst component. 1 g of solid catalyst component contains Zr.
It contained 13 mg.

-1r nitrogen exchanged 3
In a stainless steel autoclave, 2 g of the above solid catalyst component and 10 mmon of the reaction product of trimethylaluminum and water obtained in Example 3 were added, then 700 g of propylene was added, and the internal temperature was raised to 30°C. do. Then, ethylene was injected under pressure to bring the ethylene concentration to 10 mol%.
(relative to propylene)
Polymerization was continued for hours. Then, the polymerization was terminated by discharging the content gas to the outside of the system. As a result, 154 g of granular polymer was obtained, but the polymer was firmly adhered to the inner wall of the autoclave and the stirrer.The amount of deposits recovered was 35 g. Patent applicant: Showa Denko K.K. company
1゜□l

Claims (1)

[Claims] 1. (A) General formula (cyclopentadienyl)_2MR_
mX_2_-_m (M=Ti or Zr, R is carbon number 1~
A transition metal compound represented by 6 alkyl groups, X is a halogen atom, m = number of 0 to 2) and (B) a reaction product of trialkylaluminum and water are supported on (C) an inorganic oxide carrier. A method for producing a polyolefin, characterized in that the polyolefin is produced in the presence of a solid catalyst component obtained by substantially forming polymer particles.