JPS63168414A - Preparation of propylene copolymer - Google Patents

Abstract

PURPOSE:To form a copolymer which is excellent in transparency, impact resistance and sliding property, by processing a propylene-ethylene random copolymer in two steps in the presence of a stereospecific catalyst, wherein the copolymerization in the 2nd step is carried out in the presence of a specified silicon compound in a gaseous phase. CONSTITUTION:A propylene copolymer is formed in the following two steps in the presence of a stereospecific catalyst consisting chiefly of a titanium compound and an organomagnesium compound. (a) 1st step: Porpylene is homopolymerized in the presence of an inert solvent or liquefied propylene, or propylene and ethylene are copolymerized, with the ethylene content being at most 5wt.%, so that the resulting polymer amounts to 5-95wt.% of the total amt. of polymerization. (b) 2nd step: In succession to the 1st step, a random copolymerization of propylene and ethylene is carried out in a gaseous phases so that the resulting copolymer amounts to 95-5wt.% of the total amt. of polymerization to give a copolymer containing 10wt.% ethylene. The polymerization in the 2nd step is carried out in the presence of a silicon compound of formula 1 (where R<1> and R<2> are each H, 1-20C alkyl or aryl; n is 1-3,000).

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for producing a propylene copolymer. More specifically, when producing a propylene-ethylene random copolymer in two steps using a stereospecific catalyst system containing a titanium compound and an organoaluminum compound as main components,
The present invention relates to a method for producing polymer particles with high bulk density and a small angle of repose with high reactor volumetric efficiency by carrying out the second stage copolymerization in the presence of a specific silicon compound in a gas phase.

[Conventional technology]

Crystalline propylene-ethylene random copolymers containing a small amount of ethylene are widely used and processed into various films, blow molded products, injection molded products, etc.

Propylene-ethylene random copolymers have improved transparency, impact resistance, and low-temperature brittleness compared to propylene polymers, and also have better heat sealability in the film field. Further improvements can be made by increasing the ethylene content.

When producing a random copolymer by slurry polymerization in the presence of an inert solvent or liquefied propylene, the production of polymers soluble in the polymerization solvent increases and the polymerization slurry becomes viscous, resulting in a decrease in the polymer concentration. cannot be increased, and productivity decreases.

In addition, polymers that are soluble in the polymerization solvent not only cause poor heat transfer and blockage problems in the extraction tube due to adhesion to the inner wall of the reactor, but also cause a decrease in the bulk density of the polymer particles and worsening of the slipperiness. This may cause clogging of the downstream transfer process, caking in the hopper, and formation of lumps in the drying process.

Therefore, in the production of propylene-ethylene random copolymers by slurry polymerization using inert hydrocarbons or liquid propylene as a solvent, there are significant disadvantages such as lower production, or there is only slight improvement with a small amount of ethylene content. I have no choice but to compromise.

In order to solve these problems, slurry polymerization is carried out in multiple stages, and the ethylene content in the copolymer produced in the latter stage is higher than the ethylene content in the copolymer produced in the earlier stage. I know of a way to increase the ethylene content in the total copolymer. However, this method does not basically eliminate the above-mentioned troubles caused by components eluting into the medium, and is completely insufficient as a solution.

Furthermore, there are no known gas phase polymerization methods that do not use a liquid medium. Since this method does not use any liquid medium, the above-mentioned troubles caused by non-quality polymers are alleviated. However, since there is no actual medium in this method,
Heat removal is not performed sufficiently, and the formation of lumps due to mutual agglomeration of particles and adhesion to the inner wall of the polymerization tank are not improved. Furthermore, fine particles are formed due to the temporary framework of the catalyst that appears to occur in the initial stage of the reaction, and the bulk density of the resulting polymer particles is rather lower than that of polymer particles obtained by slurry polymerization.

An even bigger problem with gas phase polymerization is that the monomer concentration is low, resulting in extremely low production per unit time. In addition, it is necessary to increase the power of the blower for circulating gas for fluidization, and the power of stirring with the cypress, and the size of the volume of the gas phase reactor has a great impact not only on construction trade but also on variable costs. Therefore, low productivity must be considered a serious drawback of gas phase polymerization from an economic point of view.

The present inventors have developed a globylene-ethylene copolymer, which has excellent physical properties such as propylene-ethylene random copolymer, such as excellent transparency, impact resistance, low-temperature brittleness, and heat sealability, for industrial use. As a result of extensive research into ways to improve powder properties and polymerization methods that would yield high activity, we came up with the method below.

That is, the purpose of the present invention is to (1) obtain a polymer with excellent transparency, impact resistance, low-temperature brittleness, and heat-sealing properties; (2) prevent polymer adhesion in a reactor and drying process. (3) A method for producing a propylene copolymer that satisfies the following requirements: (3) The resulting polymer has excellent powder properties, high activity, and can be operated continuously. The goal is to provide the following.

The gist of the present invention is to carry out the first stage homopolymerization or copolymerization in an inert solvent or liquefied propylene using a stereospecific catalyst containing a titanium compound and an organoaluminum compound as main components. By conducting the polymerization in a gas phase substantially free of solvent and liquefied propylene, polymer particles with high bulk density and good slip properties are obtained in an extremely stable manner at °C, and the first stage copolymerization Sometimes, the presence of a specific silicon compound in the monomer system significantly improves the activity and increases productivity.

The present invention will be sequentially explained below.

The polymerization catalyst used in the present invention consists of a titanium-containing solid catalyst component and an organoaluminum compound, but is not particularly limited, and any known catalyst may be used.

As the titanium-containing solid catalyst component, known carrier-supported catalyst components containing solid magnesium compounds, titanium compound components, and nitrogen components can also be used, but preferably titanium trichloride is the main component. . As a material containing titanium trichloride as a main component, conventionally known titanium trichloride can be used. For example, titanium trichloride is activated by ball milling, titanium trichloride is extracted with a solvent, β-type titanium trichloride is treated with a complexing agent such as an ether, and then treated with titanium tetrachloride. In the presence of titanium trichloride and ethers whose atomic ratio to T1 is 0.7S or less, titanium tetrachloride is treated with an organoaluminum compound to form a liquid at °C, and this is further heated to form a solid. The atomic ratio of the elephant to T1 is 0./A;
The following examples include titanium trichloride.

Particularly preferred among these titanium trichlorides is an aluminum content in the atomic ratio of aluminum to titanium of 0.73 or less, preferably o, i or less, more preferably 0.02 or less, and a complexing agent. It contains.

The organoaluminum compound used as a cocatalyst for the titanium-containing solid catalyst component has the general formula A Lkt (
I R3-m (in the formula, R is a hydrocarbon group having 7 to -0 carbon atoms, X represents ].logen, and 3≧m) /,
(indicates the ridge of t). When the titanium-containing solid catalyst component is a carrier-supported catalyst component containing a solid magnesium compound, AlR3 or ARK, and A1
It is preferable to use a mixture with . On the other hand, when the titanium-containing solid catalyst component is mainly composed of titanium trichloride, AIR2X is used, but diethylaluminum chloride, di-n-propyl aluminum chloride, diethylaluminum chloride, and di-n-octyl chloride are generally preferred.

The titanium trichloride and organoaluminum compound shown above are generally used in a molar ratio of organoaluminum compound/titanium trichloride of 1 to 30, preferably 1 to 13.

In the present invention, the above-mentioned catalyst may be used as it is, but it is preferable to preliminarily polymerize a small amount of olefin onto the catalyst made of tita/trichloride and an organoaluminum compound as a pretreatment.

In the above method, titanium trichloride and an organoaluminum compound are added to an inert solvent such as hexa/, hepta/, etc., and an olefin such as propylene, ethylene, butene-1, or a mixture thereof is supplied to polymerize the mixture. Bye. This pretreatment is generally referred to as prepolymerization, and known polymerization conditions can be used as they are. The polymerization temperature is 30-0°C. The higher the polymerization rate per unit weight of titanium trichloride, the better; however, it is less than 0. /~100jj-polymer/ , 9
- It is generally in the range of Ti113. Also,
A molecular weight regulator, such as hydrogen, may be added during polymerization. Furthermore, it is preferable that the prepolymerization is carried out uniformly in a batch manner. This preliminary 1 cup is effective in improving the properties of the polymer such as bulk density.

Further, in the catalyst made of titanium trichloride and an organoaluminum compound described above, an additive for improving stereoregularity may be used as a third component and the temperature may be adjusted to 0.degree. For this purpose, N.
Various compounds containing O, P, 81, etc., and hydrocarbon compounds are used. The amount of the third component added is generally from 0.0007 to titanium trichloride, preferably from 0.0007 molar ratio to titanium trichloride.
, ooi~/.

Random copolymerization of propylene and ethylene is carried out in at least two stages.

The first stage polymerization can be carried out either in an inert solvent or in a liquid monomer, but in carrying out the present invention, it is particularly preferable to carry out the polymerization in a liquid monomer. 1st
In the stage polymerization, a propylene homopolymer or a propylene-ethylene random copolymer having an ethylene content of 5% or less is produced. If copolymerization is carried out with an ethylene content higher than the above range, it will be difficult to obtain a polymer with a high bulk density, which is one of the objects of the present invention, due to the adverse effects of components eluted into the inert solvent or liquid monomer.

For the polymerization temperature and pressure, conditions generally used in propylene polymerization can be applied, but usually θ to 100°C,
Preferably, a pressure range of 30 to 33°C and below 700 atm, preferably / -j O atm, is applied.

As the molecular ik regulator, known ones such as hydrogen and diethylzinc can be used.

The polymer obtained in the first stage polymerization is subjected to MF processing (melt flow index) in consideration of the physical property balance of the final polymer.
is adjusted so that it is in the range of 0.1 to 100g710 minutes, and in the first stage polymerization reaction, the total amount of polymerization is ! -9j heavy′jlk
% polymerize.

If the amount of polymerization in the first stage is less than 5% by weight of the total amount of polymerization, agglomeration and agglomeration of particles will easily occur in the first stage gas phase polymerization tank, and the bulk density and slippage, which is the objective of the present invention, will increase. Polymer particles with good properties cannot be obtained.

Furthermore, if the amount of polymerization in the first stage exceeds 95% by weight, the effect of carrying out the polymerization in two stages will not be achieved.

In the first stage polymerization reaction, one polymerization reactor may be used or two or more types may be used.

After the completion of the seventh stage polymerization, the homopolymer or copolymer is transferred to a gas phase polymerizer without deactivating the catalyst contained (with or without removing a portion of the reaction medium). That is, when the polymer is obtained by solvent polymerization, inert hydrocarbons and unreacted monomers are removed using a centrifuge, liquid cyclone, etc. Also, when liquid propylene itself is used as the medium, In addition to similar known solid-liquid dispersion means, it is also possible to send the mixture as it is to a gas phase polymerization vessel.

The second stage propylene-ethylene copolymerization is carried out in the gas phase in the substantial absence of an inert solvent, liquefied propylene.

The ethylene content in the copolymer produced in the second step is usually 20% by weight or less, but it is adjusted as appropriate so that the ethylene content of the entire polymer becomes a desired value. Although the ethylene content contained in the entire copolymer is 70% by weight or less, the effect of the present invention is greater as the ethylene content is higher. That is, the method of the present invention is particularly suitable for producing a copolymer containing ethylene containing 1% by weight or more. It is preferable that the ethylene content polymerized in the first stage is higher than the ethylene content in the polymer polymerized in the seventh stage.

The copolymer body produced in the second stage is a total polymer glue S-S
Manufactured so that the weight is fjk%.

The second stage polymerization is usually carried out at 30 DEG to 100 DEG C. and at a temperature of 1 to SO.

The most important feature of the present invention is that a silicon compound is added when propylene and ethylene are subsequently polymerized in the gas phase to the propylene homopolymer or random copolymer obtained by the above-mentioned first step method. By polymerizing in such a manner, extremely high polymerization activity can be obtained, and a random copolymer with no polymer stickiness and excellent slip properties can be obtained.

The silicon compound added in the present invention has a general formula number/~20
an alkyl group, an aryl group, an alkoxy group, an aryloxy group or a halogen group, and n is 3 to 3000
), preferably linear, cyclic or spiro-based polysiloxanes.

Specifically, for example, octaethylcyclotetrasiloxane C51 (Oaks) so 14, dimethylpolysiloxane C"" (CHs)zO), 1, methylethylpolysiloxane 7 CSi (OHs) (CgHs) OIB
Alkylsiloxa/11L compounds such as; hexaphenylcyclotrisiloxa; / C81(OIBHll)2
0]s, diphenylpolysiloxane CE11 (CsH
s) Arylsiloxa heptapolymer such as SO adhesive, diphenylhexamethyltetrasiloxane (CHs) sSlo C
81<CaHs)2012 ”1(CBs)3, methylphenylpolysiloxane C51(CHs) (Cass
)0], alkylarylsiloxane polymers such as /, ? -dichlorooctamethyltetrasiloxane (OH,), O1 day 10 [81 ((3H3, O], 8
1 ((3H3), haloalkylsiloxane such as CI: dimethoxypolysiloxane [81(oCHs)z).

, jetoxypolysiloxane (81(00,H,)2)
Examples include alkoxysiloxane polymers such as , and organic polysiloxanes such as diphenoxypolysiloxane polymers.

Commercially available silicone oil is also a suitable example,
Commercially available compounds and mixtures thereof with a viscosity of 01S to 106 centistokes are used. Specifically, Shin-Etsu Silicone K F-10% KIP-j-Hiro, KF-49, KF-9A ( product name) etc.

The silicon compound may be added directly to the gas phase reactor of the first stage (or may be added to the polymer after the first stage reaction is completed). In this case, it has almost no effect on the first stage slurry polymerization,
The first stage gas phase polymerization activity can be improved.

The silicon compound can be supplied as it is without a diluent, or it can be supplied after being dissolved and diluted in an inert hydrocarbon solvent or liquid propylene.

Alternatively, the silicon compound may be supplied directly into the ethylene or mixed gas of propylene and ethylene supplied to the gas phase polymerization vessel, or after being dissolved and diluted in an inert hydrocarbon solvent, liquid propylene, or the like.

The above-mentioned addition method may be any method, but a method in which the silicon compound to be added is effectively added to the former polymer/polymer or copolymer is preferred.

The amount of silicon compound to be used is based on the Ig 1 stage polymer/polymer or copolymer/X/0-6~o, i weight ratio,
Preferably! x70''''-o, oix amount ratio.

If the amount of the silicon compound added is too large, the viscosity of the silicon compound itself tends to cause the polymer particles to adhere, which is not preferable. If it is too small, the effects of the present invention will not be fully exhibited.

In the present invention, the subsequent gas phase polymerization of propylene and ethylene can be carried out in multiple stages, and the polymerization temperature, hydrogen concentration, monomer composition, and reaction amount ratio can also be changed in each reactor. When gas phase polymerization is carried out in multiple stages,
A silicon compound may be added to the step.

In the present invention, the equipment used for the subsequent gas phase polymerization is not particularly limited, and known equipment such as a fluidized bed, a stirred tank, a fluidized bed with a stirring device, a moving bed, etc. is preferably used, and the polymerization can be carried out continuously or batchwise. Let's do it.

After the completion of gas phase polymerization, the polymer extracted continuously or batchwise is subjected to inactivation treatment with alkylene oxide, alcohol, water, etc. or deashing treatment, as necessary.
The amorphous polymer may be removed using a solvent.

The polymer particles obtained in this way have high bulk density and slipperiness, so they do not cause blockage or caking in the transfer process or hopper (and the molded products obtained from the polymer have a eroded quality). have

The industrial advantages of the method of the present invention are the physical properties of random copolymers such as impact resistance, low temperature brittleness, heat sealability,
In order to create a product with higher transparency, a copolymer with a higher ethylene content is polymerized in the first stage using a solvent method, and in the second stage, a copolymer with a higher ethylene content than in the first stage is polymerized. By carrying out gas phase polymerization of a copolymer in the presence of a silicon compound, it is possible to stably obtain a product with excellent powder properties without any trouble through vortex activity during the first stage of copolymerization.

Furthermore, in the polymerization in the presence of a silicon compound, which is an important part of the present invention, regardless of the amount of silicon compound added, the amorphous polymer is It does not change the production amount, molecular weight, or co-polymerization composition.

In other words, the silicon compound has no effect on polymerization using the carrier medium method, and only the polymerization activity can be significantly improved during gas phase polymerization, which is the most desirable feature for gas phase polymerization.

〔Example〕

The present invention will be explained below with reference to Examples, but the present invention is not limited to kneading.

In addition, the meanings of the abbreviations in the examples and various measurement methods are as follows.

(1) The n-hexane extraction residue is the residue (% by weight) obtained when extracted with boiling n-hexane for 3 hours using an improved Soxhlet extractor.

(2) The bulk density ρn(,!i'/cd) is J engineering 8-
It was measured using 4 wolfberry liters.

(3) The angle of repose during rotation was measured using a three-wheeled cylindrical rotary angle of repose measuring device manufactured by Tsutsukata Rikagaku Kikai ■.

(4) mek) :ya-index MF
T (1//0 minutes is A8TM-Dl, 2.3g-70
The extrusion amount of the polymer at 230° C. load and /6 is shown.

(5) The embrittlement temperature Tb (C) was determined by A8TM D 7+4 on a test piece punched from a 2.0 oz. thick plate made by an injection molding machine.

(6) Haze is A8TM D 10OJ-4/K
Measurements were made on a 0.2 k x m press sheet in a similar manner.

(7) The melting point was measured using a differential calorimeter on the isothermally crystallized sample.

(8) Contains ethylene! (% by weight) was measured by FT-NMR spectrum analysis.

(9) Catalyst efficiency (CI) represents the total production rate of propylene copolymer (g-polymer/gTil13) produced per titanium trichloride catalyst component/I.

Further, FIG. 1 is a flowchart diagram to help understand the technical content included in the present invention, and the present invention is not limited to the temperature range shown in flowchart 4 unless it exceeds the gist thereof.

Example 1 (A) Purified toluene and 00 WL2 were added to a flask having a volume/l of solid titanium trichloride at room temperature at room temperature with sufficient displacement, and under stirring n-butyl ether t,
s, /jj (o, mol), titanium tetrachloride y? (
1,9i (0,!; mo1), diethyl aluminum chlorite coza, 6! i ((7,23 mol)) to obtain a brown homogeneous solution.

Next, the temperature was raised to yo℃, and after 30 minutes, precipitation of purple fine granular solid was observed, but it was kept as it was for 2 hours.
The temperature was maintained at 0°C.

After further holding at 96° C. for about 1 hour, the granular purple solid was separated and washed with n-hexane to obtain about toy of solid titanium trichloride.

(B) Production of titanium iochloride containing propylene polymer (
Pretreatment) Purified n-hexane and tO door were put into a SOOG flask which had been sufficiently substituted with nitrogen, and 7.9 g of diethylaluminum chloride and the solid titanium dichloride obtained in step ① above were added to Ti.
2 as Cl3. ! ;, Si+(0,0/ 4m01
) was maintained at a constant temperature of qo℃, and while stirring, propylene gas/:2. ! ; i was blown into the gas phase for about 70 minutes for contact treatment.

The solid component was then allowed to settle, and the supernatant liquid was removed by decantation and washed several times with n-hexane to obtain solid titanium trichloride containing a propylene polymer.

(0) Production of propylene-ethylene copolymer 04 mmol of diethylaluminium monochloride as a cocatalyst was placed in a t-liter autoclave sufficiently purged with nitrogen.
, methanoIJ/L/medemethyl acid 00 as the third component
After adding J mmol and charging the specified amount of hydrogen gas and ethylene gas and charging qoog of liquid propylene, the temperature of the autoclave was increased and when the internal temperature reached 60℃, the temperature was increased to 0 as above.
The propylene polymer-containing solid titanium trichloride catalyst component obtained in step 113 was injected under pressure with Kosda nitrogen to initiate a polymerization reaction. The polymerization temperature was controlled at 60°C, and the composition of the gas phase was analyzed by gas chromatography so that each composition remained constant at 2, and the ethylene to be polymerized was controlled by successively adding it.

After 3 hours of polymerization, unreacted propylene was immediately purged,
Combined powder under purified nitrogen atmosphere! Og was sampled. Next, a predetermined amount of hydrogen gas was blown into this reactor, and the
When the temperature reached .degree. C., silicone oil KF-940, 01, 9 manufactured by Shin-Etsu Chemical Co., Ltd. as a silicon compound was injected under pressure with a mixed gas of propylene and ethylene at a predetermined concentration. Pressure for 2 s
Gas phase polymerization was continued at 70° C. for 7 hours while maintaining the temperature at 9/cri. The composition of the gas phase was controlled by additionally feeding ethylene or propylene while analyzing it by gas chromatography to maintain a predetermined saponity.

After the reaction was completed, unreacted monomer gas was purged to obtain 378 g of a propylene-ethylene random copolymer.

Table 1 shows the polymerization conditions and the measurement results for each Maki.

Catalytic efficiency (e E) from analysis of T1 content in the polymer using fluorescent XW shows that the sample at the end of the first stage polymerization has /J, 7
! The tO1 final polymerization product is /If, 000, the catalytic efficiency of the copolymer by gas phase polymerization is 3/30, and the activity is 25
It was 0.

In addition, the ethylene content ti of the sample at the end of the first stage polymerization
, o weight %, n-hexane extraction residue 94.17 weight %, bulk density 0. dA g/cd, angle of repose of 33 degrees, ethylene content of the final polymer, co-hydrogen%, n-hex/extraction residue 57% by weight, bulk density o, lI7 g/cd, angle of repose 36 Although the ethylene content and non-grade polymer content have increased due to the co-stage polymerization, the bulk density has improved and the angle of repose has remained almost unchanged, resulting in a change in powder properties. A good copolymer was obtained.

Comparative Example/In Example 1, in order to achieve the same ethylene content as the final copolymer of Example 1 by only performing the first stage copolymerization, the amount of ethylene gas in the gas phase was increased and only the first stage copolymerization was performed. After a predetermined batch polymerization, propylene and ethylene were purged to obtain a copolymer.

The results are shown in Table 1, and although the ethylene content in the total copolymer was the same as that of the total copolymer of Example 1, the bulk density was 0. ．． 7 g 9/ai, the angle of repose was pg degree, the n-hexane extraction residue was 79.6% by weight, and the powder properties were poor (the copolymer had poor free flow properties).

Comparative Example In Example 1, the first stage copolymerization and sampling after the first stage were carried out in the same manner as in Example 1, and then the second stage polymerization was carried out again in liquid propylene. The ethylene fraction in the gas phase composition during the first stage copolymerization was controlled to be high so that the ethylene content in the entire copolymer was the same as in Example 1, and the copolymerization was carried out at a polymerization temperature of 60°C for 2 hours. After that, propylene and ethylene were purged to obtain a copolymer.

The results are shown in Table 1, and although the ethylene content in the total copolymer was equivalent to that of the total copolymer of Example 1, the bulk density was 0. J 7 g/cyt, angle of repose is Hirowa degree, n-hexano extraction residue is I/,! I: heavy % and powder properties are bad (
, the angle of repose is high and the fluidity is poor.

Comparative Example 3 In (0) of Example/, silicone oil KF'-9
Using propylene-functionalized solid titanium trichloride obtained by polymerization in the same manner as in the process of Φ) of Example 6, except that 6 was not used, propylene-ethylene random was prepared in the same manner as in (C) of Example 2. A copolymer was produced.

The results are shown in Table 7.

Compared to Example/, the second stage gas phase polymerization activity is low (and the catalyst efficiency is also low. Therefore, the ethylene content is low, and the properties of the random copolymer are poor compared to Example/.

In Examples Co to Example 0), the type and amount of the silicon compound shown in Table 1 was substituted for silicone oil KP-96.
Using propylene polymer-containing solid titanium trichloride obtained by adding C and polymerizing in the same manner as in step (b) of Example No.
A propylene-dethylene lantam copolymer was produced in the same manner as in Example 0.

The results are shown in Table 7.

As in Example 1, the first stage polymerization yielded a copolymer with high catalyst efficiency and good powder properties.

Example! In Q) of Example 1, silicone oil KF-940,061 was supplied together with the propylene polymer-containing solid titanium trichloride catalyst component at the start of the polymerization in the first stage, and silicone oil KF-94 was supplied at the start of the polymerization in the second stage. A glopyrene-ethylene random copolymer was produced in the same manner as in Example 1 (0) except that .

The results are shown in Table 1.

The catalyst efficiency, n-hexane extraction residue, bulk density, and angle of repose in the first stage polymerization were unchanged and the same values as in Examples 7 to q were obtained, and the catalyst efficiency and activity in the first stage polymerization were the same as those in Examples 7 to q. As with 1-Dan, the temperature was significantly improved compared to Comparative Example/without addition, and a copolymer with good powder properties was obtained.

Example 6 (A) At 0 in Example/, it was heated separately to 70°C, and purified nitrogen was added to it while maintaining the internal pressure at ψ-.
The propylene-ethylene copolymer slurry after the first stage polymerization, which had been polymerized in the same manner as in Example, was fed in small batches into an autoclave which was operated at a flow rate of 1Z, and the propylene was flash-purged. After the supply was completed, the flashed copolymer Dac I was sampled under a purified nitrogen atmosphere.

The copolymer remaining in the first stage polymerization tank was 103I.

(B) Next, a predetermined amount of hydrogen was blown into the autoclave into which the copolymer was transferred, and silicone oil KF-9A O
, 0/'iff: A mixed gas of ethylene-propylene having a predetermined roughness was injected under pressure. -2 pressure! The gas phase polymerization reaction was continued at 70°C for 7 hours while maintaining r'Q/ad. The composition of the gas phase was controlled by additionally feeding ethylene or propylene to a predetermined concentration while analyzing it by gas chromatography.

After the reaction was completed, unreacted monomer gas was purged to obtain a -≠/9 propylene-ethylene random copolymer.

Table 1 shows the polymerization conditions and various measurement results.

The aX of the copolymer after the first stage polymerization is 14q3o, and the ○E of the final copolymer is / 7.9 I
O, and the OR of the copolymer obtained by gas phase polymerization is 5oso,
Activity was 5050.

After the first stage polymerization, the ethylene content of the copolymer was 6.6% by weight, the n-hexane extraction residue was 6.6% by weight, and the bulk density was 0. asf//cri1. The angle of rest is 36 degrees,
Ethylene content of the final copolymer: 5.3% by weight, n-hexane extraction residue t4. cosit%, bulk density o, qtg
The hawk had a resting angle of 37 degrees.

Example 7 In 0 of Example 1, instead of copolymerizing the seventh stage, only globin was polymerized. Polymerization is at a temperature of 70
After polymerization, the propylene was purged,
SSg sampling of the polymer powder was carried out.

Next, in the same manner as in the second stage copolymerization in Example 1 (0), a predetermined amount of hydrogen was fed, and as a silicon compound, silicone oil IF-91゜obg manufactured by Shin-Etsu Chemical Co., Ltd. was mixed with propylene and ethylene mixed gas. It was press-fitted. Pressure 2 J kg/
cdl, and gas phase polymerization was carried out for 215 hours while maintaining the polymerization temperature at 70°C.

The composition of the gas phase was controlled by additionally feeding ethylene or propylene while analyzing it by gas chromatography to maintain a predetermined concentration.

After the copolymerization was completed, unreacted gas was purged to obtain a copolymer of 4t and θI.

The results are shown in Table 2.

The first-stage activity was high as in Example/-4, and the copolymer had good powder properties.

Example g The first stage copolymerization was carried out in the same manner as in Example ←), and when the first stage copolymerization was carried out in the gas phase, 6 g of silico/oil KI+'-96 was added and carried out. Example 1
Copolymerization was carried out at a polymerization temperature of 70° C. for 3 hours using the same gas composition as in (0). After the copolymerization was completed, the mixed gas was purged to obtain a copolymer.

The results are shown in Table 2. The fraction of copolymerization amount in the second stage is 3θ
%, the powder properties were better than when copolymerized in liquid propylene, the catalyst efficiency was high, and high activity was obtained.

Example 9 The first stage copolymerization was carried out in the same manner as in Example 1 (0) (however, the catalyst amount was 31 m9, di-n-propyl aluminum chloride J, , 7 mmol,
Methyl methacrylate θ, ozrnmol 1), the ethylene fraction in the gas phase composition is about 1/co as in (9) of Example 1,
Copolymerization was carried out at a polymerization temperature of 60° C. for 7 hours.

After completing the first stage, unreacted globylene, ethylene, and hydrogen were purged, and the copolymer powder hog was sampled under a purified nitrogen atmosphere.

Thereafter, silicone oil KF-940,049, hydrogen, propylene, and ethylene were added to the predetermined composition in the same way as the 00 first stage copolymerization on the undercurrent side, and copolymerization was carried out at a polymerization temperature of 70°C for 3 hours. I did it. After the copolymerization was completed, the mixed gas was purged to obtain a copolymer.

The results are shown in Table 2. The fraction of the second stage copolymer is 71
．． Although it was set at 3% by weight, the powder properties were good with no significant deterioration, and the catalyst efficiency was high, resulting in high activity.

Example i.

(A) Production of solid titanium trichloride catalyst component Toluene solution was placed in an autoclave with a capacity of 100 mm, which was sufficiently purged with nitrogen.
b and titanium tetrachloride jQ mob, di-n-butyl ether SOmol are added. While stirring and maintaining the stiffness at λ5℃, add 5m0 of diethyl aluminum chlorite.
1 was added to obtain a brown homogeneous solution.

Next, the temperature was raised to IO°C, and after 30 minutes, no precipitation of purple ridge-like solids was observed, but the mixture was kept at IIO°C for an additional hour.

The temperature was then raised to 96°C and held for about 7 hours, after which the granular purple solid was separated and washed with n-hexane, and then heated to about 96°C.
g of solid titanium trichloride was obtained.

Next, l-Sl of n-hexane was charged into an autoclave with a capacity of 2,001 kg, which was sufficiently purged with nitrogen, and di-n-hexane was charged with stirring.
4 mol of propylaluminum chloride and the above solid titanium trichloride-based catalyst complex were charged so that the amount of T i O13 was about 0.5 mol. Then, the internal temperature was adjusted to 30° C., and while stirring, propylene gas was started to be blown into the reactor, and the blowing of propylene gas was continued until the amount of polymerized propylene reached /soog. Thereafter, the solid was separated and washed repeatedly with n-hexane to obtain polypropylene-containing titanium trichloride (titanium-containing solid catalyst component).

(B) Production capacity of propylene-ethylene random copolymer/! An apparatus was used in which a reaction tank of 00 g with a stirrer and a gas phase reactor with a spiral type stirrer with a capacity of 7001 were connected in series.

In the first reactor, liquid propylene was used as a heating medium at ℃, the titanium-containing solid catalyst component obtained in step ① above, diethylaluminium chloride as a cocatalyst, and the third component were methyl methacrylate and H2 gas as a molecular weight regulator. , ethylene was continuously supplied as a comonomer to the reaction tank at a predetermined ratio, and the amount of propylene supplied was adjusted so that the polymerization temperature was tO ℃ and the residence time was 3 hours. A polymer was produced.

The above polymer slurry is continuously fed to the first gas phase reactor, and the pressure of the reactor is increased to 2! r kg/ffl
, while adjusting the gas composition so that (ethylene/ethylene tenpropylene/) was 4z mo1% by gas chromatography analysis.
Gas phase polymerization at 7° C. was carried out by circulating a mixed gas of hydrogen, ethylene, and propylene.

The temperature of the gas phase reactor was adjusted to 70°C by adjusting the temperature of the circulating mixed gas. Further, the polymer was continuously extracted while adjusting the amount of residence so that the residence time of the polymer was equal to S time to obtain a powdery copolymer.

The mixed gas fed to the gas phase polymerization vessel includes silicone oil KF-940 manufactured by Shin-Etsu Chemical Co., Ltd. as an n-hexane diluted liquid from the first reactor, and propylene copolymer fed to the second reactor. The amount of silicone oil is
It was continuously supplied so that the amount was 0 ppm.

The ethylene content of the copolymer produced in the first polymerization tank is adjusted by gas chromatographic analysis of the composition of ethylene and propylene so that the ethylene content of the copolymer produced in the second polymerization tank is % by weight. The ethylene content of the combined product was adjusted to tM% while analyzing the gas composition.

Continuous operation was carried out in this manner for lj days, during which time the first
There was no adhesion trouble in both the second reactor (and stable operation was possible. After the operation was completed, the gas phase reactor was opened and inspected, but there was no adhesion on the vessel walls, etc. (no lumps were observed). I got angry.

Typical values of activity etc. during continuous operation are shown in Table 3.

Comparative Example G A solid titanium trichloride catalyst component obtained in the same manner as in Example 6 (2) was used, except that the silicone oil used in Example (B) was not added. Continuous polymerization was carried out in the same manner.

The results are shown in the second column.

Since no silicon compound was used, the catalyst efficiency in the gas phase polymerizer was low, and the noetin content in the obtained copolymer was also low (the characteristics of the random copolymer were worse than in Example 9.

Table 2 Table 3 Old l Silicone oil/I/KF-qb; dimethylpolysiloxane 2 Silicone oil KF-deq Nidimethylhydrozine polysiloxane ax 3 Silicone oil KF-, 14: Methylphenylpolysiloxane [invention Effect] According to the present invention, polymer particles having high bulk density and good slip properties can be obtained stably with high activity, and therefore are industrially useful.

Claims (4)

[Claims] (1) Using a stereospecific catalyst system containing a titanium compound and an organoaluminum compound as main components, (a) In the first step, in the presence of an inert solvent or liquefied propylene, propylene homopolymerization or ethylene content of 5 Random copolymerization of propylene and ethylene is carried out in a proportion of 5 to 95% by weight based on the total polymerization amount, and (b) In the second stage, random copolymerization of propylene and ethylene is carried out in a gas phase to reduce the total polymerization amount. This is a method for producing a propylene-ethylene random copolymer having an ethylene content of 10% by weight or less, in which the ethylene content is 95% to 5% by weight. Formula ▲ Formula,
There are chemical formulas, tables, etc. ▼ (However, R^1 and R^2 represent a hydrogen atom, an alkyl group, an aryl group, an alkoxy group, an aryloxy group having 1 to 20 carbon atoms, or a halogen atom, and n is 1 to 3000. 1. A method for producing a propylene copolymer, which comprises the presence of a silicon compound represented by (2) The manufacturing method according to claim 1, wherein the ethylene content is 4% by weight or more and 10% by weight or less. (3) The production method according to claim 1 or 2, wherein the stereospecific catalyst system contains titanium trichloride and dialkyl aluminum chloride as main components. (4) The stereospecific catalyst system has an aluminum content of 0.15 or less in terms of the atomic ratio of aluminum to titanium, and mainly comprises a solid titanium trichloride catalyst complex containing a complexing agent and an organoaluminum compound. The method according to claim 1 or 1, characterized in that the catalyst system is a catalyst system in which: