JPS6147712A - Preparation of propylene copolymer - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a polymerization method for providing a propylene block copolymer with high rigidity, high impact strength, and good flowability while suppressing the by-production of highly active and low crystalline components. It is.

Although crystalline polypropylene produced using prior art stereoregular catalysts has excellent properties such as rigidity and heat resistance, it has a problem of low impact strength, particularly low impact strength at low temperatures.

As a method to improve this point, a method of producing a block copolymer by stepwise polymerization of propylene and ethylene or other olefins is already known (Japanese Patent Publication No. 173-//, No. 230, Japanese Patent Publication No. 173-//, No. 230, / & AJ
No. 1, special public Akihiro Gu, 206λ1, special public Akihiro≠2-2≠
j23, special public Sho Geta-30mu cicada, special public Sho tAza-2
Yo7♂/, JP-A to-Iij Kota No. 6, JP-A 33-
33712, Japanese Unexamined Patent Publication No. Sho TP-IIOO 7a, etc.)
.

However, when propylene and ethylene are polymerized in two stages or in multiple stages, although the impact resistance is improved, there is an industrial problem that a large amount of low-crystalline polymer is produced as a by-product because it contains a copolymerized portion. Contains points. Therefore, many attempts have been made to reduce the by-product amorphous content.

On the other hand, titanium trichloride type catalysts are well known as olefin stereoregular catalysts, but they have low activity and require a decatalyzation step to remove catalyst residues from the produced polymer.

It is known that introducing a magnesium compound into a solid component is effective as a method for greatly improving activity (Japanese Patent Publication No. 39-12101, Japanese Patent Publication No. 7-767).
No. 6, and Tokuko Sho≠7-1I6242). However, it is known that when diolefins are polymerized by these methods, the activity is very high, but the stereoregularity is poor and the practical value is low.

Therefore, in olefin polymerization using Ziegler-type catalysts containing magnesium compounds, various methods have been proposed to improve the stereoregularity of the resulting polymer (Japanese Patent Application Laid-open Akihiro 7-ta, r≠λ, Kaisho y-/2tj!PO issue, JP-A-Sho!/-!7719). These methods are characterized in that a solid catalyst component containing a titanium compound and a magnesium halide compound further contains an electron donor such as an ester or an amine.

A method for producing a propylene block copolymer using these catalyst systems has also been proposed (Japanese Patent Application Laid-Open No. 2-210≠!, Japanese Patent Application Laid-Open No. 33-1989-ZatO≠). However, these methods are unsatisfactory in practical terms because they produce a large amount of amorphous by-products.

Furthermore, in order to improve this, St -0-C
Alternatively, it has been proposed to add an organosilicon component having an 8l-N-C bond (published in Japanese Patent Application Laid-open No. 2003-110001-J30/). As a result, the by-product amorphous content was greatly improved. However, in the method according to this publication, the molecular weight of the ethylene/propylene rubber part that affects impact resistance is small, and therefore the rubber produced is easily extracted into the polymerization solvent, resulting in amorphous by-products. The resulting polymer becomes sticky, aggregates, or sticks, which tends to cause operational troubles. In addition, this method has the drawback that the flowability of the polymer in the mold is poor, but the reason for this is the viscosity of the crystalline polypropylene portion synthesized in one step, and the lower the viscosity, the better the spiral flow. In the previously reported method, the molecular weight of the ethylene/propylene copolymer portion and/or polyethylene portion is small, so in order to match the viscosity of the entire polymer, the viscosity of the crystalline propylene portion formed in seven stages must be increased. Therefore, the spiral flow inevitably deteriorates, and as a result, the molding cycle becomes longer, which is inconvenient in practice.

SUMMARY OF THE INVENTION The present invention aims to provide a solution to the above points and seeks to achieve this object by an improved process for producing propylene copolymers, which consists of the use of specific catalysts and the implementation of specific steps. It is something.

Therefore, the method for producing a propylene copolymer according to the present invention is as follows:
In the method of producing a propylene copolymer by carrying out the following step (n) in the presence of the following catalyst (I), at least the polymerization of step (2) is carried out in the coexistence of a rogen-containing compound. It is characterized by:

(1) Catalyst This catalyst consists of a combination of the following components (A) to (C).

(A) Solid catalyst component containing magnesium, titanium, and halogen as essential components (Bl Organoaluminum compound (C) Electron donor (n) The process consists of the following (1) and (2), and the total ethylene content This is a process for producing a block copolymer in which I is 3 to 10% by weight.

(1) A step of polymerizing propylene alone or a propylene/ethylene mixture having an ethylene content of 5% by weight or less in one or multiple stages to form a polymer in an amount corresponding to 60 to 5% by weight of the total weight.

(2) A step of polymerizing a propylene/ethylene mixture corresponding to an ethylene content of i, o-1oo in one step or in multiple steps.

Effect By producing a propylene copolymer by the method according to the present invention, a copolymer having high activity and high stereoregularity, and in which the Z-stage propylene/ethylene copolymer composition and/or polyethylene portion has a high molecular weight can be obtained. Can produce combinations.

As a result, the molecular weight of the propylene/ethylene rubber part increases, which reduces the elution of by-product amorphous components, eliminates stickiness of polymerized powder, and reduces operational troubles due to agglomeration of polymer powder. It was also cost effective. It has also been found that since the molecular weight of the propylene/ethylene copolymerized portion increases, it is possible to further reduce the molecular weight, thereby improving the spiral 70-, that is, the flowability of the polymer.

That is, according to the present invention, the material has high rigidity and good low-temperature impact strength.
We were able to produce a propylene block copolymer with high activity and good fluidity at low cost and without any operational troubles.

The catalyst used in the present invention consists of a combination of components A) to C). In addition, the polymerization step (II) of the present invention consists of steps (1) and (2). ), it can be said that the catalyst of the present invention consists of a combination of component (A).

The solid catalyst component is a highly active solid catalyst component containing magnesium, titanium, and halogen as essential components. This solid catalyst component may contain other elements, organic compounds, etc. in addition to the above-mentioned essential components. A typical component such as is an electron donor compound. Furthermore, this solid catalyst component may be diluted with an inorganic or organic diluent.

Methods for producing such solid components are already known, some of the suitable ones being exemplified below.

(1) A method of manufacturing by grinding magnesium halide in the presence or absence of a grinding aid, and co-pulverizing or contacting it with a titanium compound in a liquid state. This may be further contacted with an electron donor and/or a halogenating agent (
JP-A-53-≠yottt issue, JP-A-Sho! ! -Refer to each publication of Taojio issue).

(2) By dissolving the magnesium compound in an electron donor and removing part or all of the electron donor complexed with the magnesium component with an electron donor extractant such as a halogenating agent or a reducing agent, Precipitates magnesium compounds,
A method of producing a catalyst by contacting this with a titanium compound and, in some cases, a halogenating agent (Japanese Patent Application Laid-open No.
No. 3, JP-A-56-111, JP-A-Sho! I-/1r37
01, Appetizers, and Japanese Patent Application Laid-Open No. 13709).

1a) A method of producing a catalyst by bringing an organomagnesium compound such as a Grignard reagent into contact with a halogenating agent, etc., and contacting this with a titanium compound (Japanese Patent Application Laid-Open No. 32-1989/Hiroshi 672)
No. 3.3-3-1009).

In producing this solid component, the starting magnesium compound raw materials include (i) magnesium oxide, magnesium hydroxide, (←) magnesium carboxylates such as magnesium acetate and magnesium stearate, (e) magnesium methoxide and magnesium ethoxy. Alkoxymagnesium such as ←) Allyloxymagnesium such as magnesium phenoxide and magnesium crezoxide, (=h) Magnesium cybaride such as magnesium chloride and magnesium bromide, (H) Allyloxymagnesium halide, alkoxymagnesium Examples include halide derivatives such as hashide and hydroxymagnesium halide, organomagnesium compounds such as (t) Grignard reagent, and complexes of organomagnesium compounds with electron donors and halides.

Titanium compounds for treating such magnesium compounds include (()Ti(OEt)+1, TI(OIa
.

Pr)II%TI (On Bu)Tetraalkoxytitanium such as II, (o)Ti (OEt)3C1, TI
(OEt) 2c12, TI (OK t) C15, T
i (O1aoPr)5C1%TI (OlaoPr)
2C12, TI (Ojao Pr) C13, T1
(0nBu)5 CI, Ti(OnBu)2
C1'2, Ti (On Bu) 015, TI (
OC8R17)3C1, Ti (o C8R17)2
C12, Ti (OCB R17) C15, TI (
OCH2CH(C2H5) CIIH9) CI! l,
Tt (ocr, u5) C15, TI (ortho-flexixi) C15, TI (OCH2C6H3) CH3
Alkoxyhalogenated titanium prepared by Tl (OR)HX←, n, etc., riTmuC111%TI Br4
An example is titanium tetrahalide.

Particularly preferred among these is Ticiq.

Alternatively, it may be a molecular compound obtained by reacting TiXq (where X represents .logen) with an electron donor.

Ti ciq -CB5 COCH3, T amount C111
・CB5 COOC2R5,'rict11・C6H5
COOC2H5, Ticiq-C6R5COC1,
Examples include TiC1%・C11H110.

An electron donor can be added to the solid component and is a preferred embodiment.

As the electron donor, organic acid esters are preferred, and any generally known organic acid esters can be used. As an organic acid ester, the number of carbon atoms/
-Aliphatic and alicyclic carboxylic acid esters derived from saturated or unsaturated or unsaturated aliphatic and alicyclic mono- or polycarboxylic acids with a carbon number of 7 to /2
Aromatic carboxylic acid esters derived from aromatic heptano- or polyhydric carboxylic acids of about 3 are preferred.

Specifically, organic acid esters include ethyl acetate, vinyl acetate, cellosolve acetate, methyl acrylate, methyl methacrylate, diptyl maleate, diethyl malonate, α
-Ethyl phenylisobutyrate%/1λ-cyclohexanecarboxylic acid di,2-ethylhexyl, methyl benzoate,
Examples include ethyl benzoate, cellosolve benzoate, ethyl p-)rulyate, ethyl 0-methoxybenzoate, butyl 0-glopionylbenzoate, ethyl acetylsalicylate, diethyl phthalate, dihexyl heptatalate, triethyl trimellitate, etc. be able to. These may be synthesized in-system from, for example, an acid halide and an alkoxy compound or alcohol. Moreover, two or more types of these can also be used in combination.

The halogen atom of 'rix4 is preferably fluorine, chlorine, hydrogen, iodine, or a mixture thereof, with chlorine being particularly preferred.

The quantitative ratio relationship is as follows. That is, the Ti/Mg molar ratio in the solid catalyst is preferably in the range of /X10 -/, and the C1/Mg molar ratio is 0. The organic acid ester/Mg molar ratio is preferably in the range of
It is preferable to be in the range of ×10 to /.

Organoaluminum Compound (Component B)) The following are suitable as the organoaluminum component (B) of the present invention.

(1) General formula Rla R2b AI Xc (O
R') d (Here, R1, R2 and R5 are hydrocarbon residues having a carbon number of about J to J, which may be the same or different, or hydrogen, and X is a rogen atom). a+b+c+d=
An organoaluminum compound represented by J with O≦a≦3, O≦b≦3, O≦a (J, 0≦d×3), (11) General formula MAI R- (where M is a member of the periodic table) An organoaluminum compound represented by a Group 1A alkali metal, R is a hydrocarbon residue having a carbon number/~.

Specific examples of organoaluminum compounds belonging to (1) include a) trialkylaluminum such as triethylaluminum, triisophthylaluminium, and tri-n-hexylaluminum, and a) diethylaluminum hexachloride, diisobutylaluminum monochloride, and ethylaluminum. sesquichloride, alkyl aluminum halides such as ethyl aluminum dichloride,
c) Alkylaluminum hydrides such as diethylaluminium hydride and diisobutylaluminum hydride; and 2) alkylaluminum alkoxides or alkoxides such as diethylaluminum ethoxide, diethylaluminium butoxide and diethylaluminium phenoxide.

These can be used alone or in combination of two or more. In addition, these can be treated with another compound to modify the same R
It can also be used as la R2b AI Xc (OR)d.

For example, it can be used as an alkyl halide by mixing triethylaluminum and an alkyl halide, or it can be used as a dialkylaluminum alkoxide such as triethylaluminum alcohol or ketone.

Compounds belonging to (11) include Li Al (C2
H3)11 and LiA1 (CIIH9)111.

If the amount of organoaluminum compound (B) used is too small, the solid catalyst will be insufficiently activated, and if it is too large, it will cause deactivation due to overreduction, etc. It is preferably within the range of ~1ooo.

Electron Donor (Component C)) The following are suitable as electron donors for improving the stereoregularity of propylene polymers.

(i) General formula R% R618t (OR'),
Xh (R', R6 and R may be the same or different and have about 1 carbon number/-1 hydrocarbon residue or hydrogen, X is) 1
0 Gen atom is shown. ζHere, e tenf + g + h
”≠, 0≦e≦3, O≦f≦3, /≦g≦≠, O≦h
≦3).

This compound can also be synthesized in-system. For example, a compound having an 8l-0-C bond can also be synthesized from phenyltrichlorosilane and an alkoxy-containing compound or alcohol.

Specific examples of (1) include ethyl silicate, butyl silicate, phenyl silicate, ethyltriethodisilane, ethyltriethodisilane, phenyltrimethoxysilane, enyltriethoxysilane, methyltriphenoxysilane, vinyltriethoxysilane, Dimethyldimethoxysilane, diethyldimethoxysilane, diethyldimethoxysilane, phenylmethyldimethoxysilane,
Examples include trimethylmethoxysilane, triphenylmethoxysilane, and chlortrimethoxysilane.

(11) Specific examples of the ester compound (11) include ethyl acetate and cellosolve, methyl methacrylate, diethyl maleate, α-
Examples include ethyl nylinobutyrate, ethyl benzoate, ethyl o-methoxybenzoate, diethyl phthalate, and diheptyl phthalate.

(1+1) The specific side layer of the ether compound (Ill) is isoamyl ether,
Examples include diphenyl ether, tetrahydrofuran, and cineol.

(1v) Other electron donors peroxides such as diα-cumyl peroxide, phosphorus-containing compounds such as triethyl phosphite, λ, 2
．． 6. Amine compounds such as A-tetramethylpiperidine can be exemplified.

Among these, preferred is the organosilicon compound (1). - The electron donor of component C) is preferably used in a molar ratio of organosilicon compound/A1 used during polymerization of 0.07 to 0.0. Particularly preferably, it is within the range of 0.0j to 0.j.

In addition, these electron donors can also be used individually or in combination of two or more types.

-・Halogen-containing compound (component D)) In order to increase the molecular weight in the second polymerization step, improve the flowability of the polymer, and reduce the extracted rubber component, a halogen-containing compound is introduced into the catalyst system. It is effective to do so. The reason why such an effect is obtained by component D) is not clear, but the reason is that the halogen-containing compound reacts with the organoaluminum component (B) to transform the organoaluminum component into a - halogen, or the solid melt It is thought that it reacts with the active sites of component (A) to modify the state of the active sites.

As the halogen-containing compound as component D), if it is a compound that releases halogen atoms relatively easily,
Any organic or inorganic halide can be used.

Specifically, (-1) HCI%NaCl, KCI,
Periodic table of CuC1, CuC1z, Ag C1, etc. ■ Genus cumulative halide, (b) Ca C12,5rC12, Zr
Same m group element halide such as Cl2, CdCl2, e→B
Same m-group element halide J=)81 such as C15 and AlCl3
cx4, Si (OEt) C15, Go
C111, Zr C111, Zr (OBu)
CI! 1st class m-group element halide, (e)PCl5
, PCl3, P OC15,5bC15, VCl5, etc. m group element halide, 180c1.5OC12, CrC
Halides of the same group elements such as l3, MoCl5, TV C15 ()lcL2.13r Ch, l C15, -C
Halides of the same group elements such as IB, Iec12, FeCl
3. Same m-group element halides such as CoCl2 and NiCl2,
elJ) Methyl iodide, ethyl bromide, tert-butyl chloride, ethylene dichloride, a7tyl chloride,
Examples include organic compounds such as carbonyl chloride.

Among these, preferred is AlCl3.5IC14
, Ti (OR)2 C12, ZrC1q, Zr(O
R) C15, Zr(OR)2C12, PCl5, PCl
5 and FeCl3. These can be used alone or in the form of a complex with an electron donor, and it is also possible to use one or more of these in combination.

In the halogen-containing compound of component D), the rhodane atom/Al atomization in the halogen-containing compound used during polymerization is o,
It is preferably within the range of oi to l.

The halogen compound can be added at any time when the effects of the present invention are observed. Preferably, it is added before propylene/ethylene copolymerization in the fourth polymerization step.

Polymerization Step The polymerization step of the present invention, which is carried out in the presence of the catalyst described above, consists of at least two steps. It is industrially advantageous to carry out steps (1) and (2) in this order.

Step (1) In step (1), propylene alone or ethylene content! Propylene of less than weight percentage, preferably less than OJ weight%
The ethylene mixture is fed to the polymerization system containing the catalyst to form, in one or more stages, an amount of polymer corresponding to well over 60 to 100 g of the total polymerization amount.

Engineering! In (1), when the ethylene content in the propylene/ethylene mixture increases to a greater extent, the bulk density of the final copolymer decreases and the amount of by-product of low crystallinity polymer increases significantly. Furthermore, when the polymerization ratio is at the extreme end of the above range, a phenomenon similar to that occurring when the ethylene content in the dipropylene/ethylene mixture is high occurs. On the other hand, if the polymerization ratio is made larger than the above range, the by-product of the low-crystalline polymer tends to decrease, but this is not preferable because the impact strength, which is the purpose of block copolymerization, decreases.

The polymerization temperature in step (1) is approximately JO-40°C, preferably SO-0°C. Polymerization pressure is 1~30~A
- It's about.

In step (1), it is preferred to use a molecular weight regulator so as to give favorable results in the fluidity of the final polymer, and hydrogen is preferred as the b0 molecular weight regulator.

Step (2) In step (,2), a propylene/ethylene mixture with an ethylene content of 20 to 100% by weight is further introduced, and an amount of the propylene/ethylene mixture having an ethylene content of 20 to 100% by weight is added in 7 stages or in multiple stages to an amount corresponding to ≠0% by weight of the total polymer. form a union.

If the polymerization ratio in step (2) is less than the above range, the impact resistance (especially low-temperature impact resistance) will be poor, and if it exceeds the above range, the by-product of low crystalline polymer will greatly increase and the viscosity will decrease. The rise is significant.

In step (2), other comonomers may be present.

Suitable comonomers include, for example, /-butene, /-
α-olefins such as pentene and /-hexene can be exemplified.

The polymerization temperature in step (2) is 3θ to 90°C, preferably y
~to°C. ji polymerization pressure, /~30 Kp
/about 2 circles.

When moving from step (1) to step (2) or when moving from step (2)
), it is preferable to purge propylene gas (including ethylene gas in some cases) and hydrogen gas before proceeding to the next stage.

In step (2), the molecular weight regulator may or may not be used depending on the purpose. That is, when it is desired to increase the impact resistance of the final polymer, it is preferable to carry out this step in the substantial absence of a molecular weight modifier, whereas when emphasis is placed on transparency, gloss whitening, etc., the molecular weight modifier is preferably carried out. Can be used.

Note that among steps (1) and (2), at least step (
As mentioned above, 2) is carried out in the presence of the halogen-containing compound (D).

Polymerization Method The copolymer according to the present invention can be produced by any of the batch, continuous, and semi-continuous methods. Also,
It was carried out in a gaseous monomer without using heptane or other inert hydrocarbons or a selective medium using the monomer itself as a medium, and it is also possible to carry out in a combination of these. .

It is also possible to carry out preliminary polymerization, that is, polymerization conducted under milder conditions than the main polymerization, before the solid catalyst is subjected to the main polymerization.

Experimental Examples Example-1 l) Synthesis of solid catalyst component) Dehydrated and deoxygenated n-hebutane λ, J-liter was introduced into an autoclave with an internal volume of 10 liters which was sufficiently purged with nitrogen, and then 2.0 liters of MgCl2 was introduced. 0 mol, Ti(
3.2 mol of 0-nBu)4, then n-C4H90
0-0 tamol of H was introduced and reacted at 0°C for 2 hours to form a homogeneous solution.

After the reaction was completed, the temperature was lowered to Io°C, and then 30θ milliliter of methylhydropolysiloxane (20 centistokes) was introduced, and the reaction was allowed to proceed for 3 hours.

After washing with the generated solid component n-hebutane and taking out a portion for compositional analysis, the results showed that TI = /4t, 2
The weight was Mg"Hiro, 3% by weight.

An amount equivalent to 2 moles of the above reaction product in terms of Mg atoms was slurried with n-hebutane to a concentration of 320 #1 solid/liter, and 81 C142.0 moles were mixed with 3
The mixture was introduced at 0°C for 1 hour and reacted at 30°C for 30 minutes.

Then diheptyl phthalate 0. / j j mole to 3
The mixture was introduced at 0° C. for 3θ minutes, and reacted for 1 hour at SO'C.

After the reaction was completed, the mixture was washed with 1 liter of n-hebutane.

Next, titanium tetrachloride/, (7!7ttle) was introduced at 3θ°C and reacted at 90°C for 2 hours. After the reaction was completed, the supernatant was extracted, and then the same amount of T1 c14 was introduced.
The reaction was carried out at 90°C for 2 hours. After the reaction was completed, the supernatant liquid was taken out and washed with 1 liter of n-hebutane. Furthermore, 3 liters of n-hebutane was introduced and stirred at 70"C for 2 hours. After the supernatant liquid was taken out, it was washed three times with 1 liter of n-hebutane. 273 ml of TiC1q was introduced again. The reaction was carried out for 2 hours at 50°C. After the reaction was completed, the reaction mixture was washed five times with 3 liters of n-hebutane to obtain a solid catalyst component (A).

The composition of the solid catalyst component is Ti=2. weight%, Mg =
/ , t, Hirowt %, dihebutyl phthalate;〃.

It was % by weight.

2) Prepolymerization In a 3 liter stainless steel stirring tank with stirring and temperature control device, sufficiently dehydrated and deoxygenated n-hebutane was added in SOO ml, triethylaluminum (B)≠, 3 grams, diethylaluminum chloride (B) 0. ≠sf ram, solid catalyst component (A)S
Gram was introduced. The temperature inside the stirring tank was set at 3° C., propylene was introduced at a constant rate, and propylene was polymerized for 30 minutes. After the polymerization was completed, it was thoroughly washed with n-hebutane. The polymerized amount of propylene was 0.7 grams of polypropylene per gram of solid component.

3) Polymerization internal volume/! After sufficiently replacing the interior of the Q liter stirred polymerization reactor with propylene, 3 liters of n-hebutane, 2.7 grams of the prepolymerized melt (A), triethylaluminum (B), 2.j, θ grams, and 10.7 grams of diphenyldimethoxysilane (C) at 60°C.
was introduced under a propylene atmosphere.

In the first stage polymerization, the polymerization reactor was heated to 63°C, and propylene was heated to 2.5°C. The introduction was carried out at a constant rate of oAKy/hour for 3 hours.

During this time, hydrogen was also introduced so that the hydrogen concentration in the gas phase was 3.0 vol.

After 3 hours, the introduction of propylene and hydrogen is stopped and the polymerization continues for i, z hours, t,! Continued at i°C.

Thereafter, the gas phase gas was purged until the gas phase line pressure reached Q, Kp10n 2G (here, a portion of the polymer produced in the first stage was removed to examine its physical properties).

Then, zirconium tetrachloride (D), 2o, r grams was introduced at 6.5°C under a propylene atmosphere.

In the second stage polymerization, the propylene/ethylene mixing ratio was 20/
This was carried out by feeding the mixture at a weight ratio of 1 O at a constant rate of λ, 95 m/h for 1 h. The polymerization temperature is
The temperature is 63°C.

The polymer slurry obtained in Tonoyo 5 was centrifuged to separate the polymer, and then dried in a dryer.
2 kg of product powder was obtained.

The bulk density of this product was θ, 4t9cbc.

The details of the results were as shown in Table/.

Comparative Example-/ Polymerization was carried out in the same manner as in Example 1 except that zirconium tetrachloride was not used as polymerization ≦ machining (D), and Table 7 was obtained.
I got the result. In this case, due to by-products of low crystalline polymerization,
Powder agglomeration was observed in the dryer.

Example - Inner volume 1. After sufficiently replacing the propylene in the stirred polymerization reactor with t liters, 200 milliliters of n-hebutane and the prepolymerized phosphorus catalyst (A) described in Examples/Description were added to the catalyst equivalent of 75 milliliters.
Milligrams, triethylaluminum (B) λ! θ milligrams, 107 milligrams of diphenyldimethoxysilane (107 milligrams) were introduced at 60° C. under a propylene atmosphere.

In the first stage polymerization, after adding hydrogen in an amount such that the overall MFR is about t, propylene is added at a polymerization temperature of 4j'C! ! ,
The mixture was introduced at a constant rate for 3 hours at a rate of 17 hours.

After 3 hours, the introduction of propylene was stopped, and the polymerization was further continued at 65° C. for 1 hour.

Thereafter, the gas phase was purged until the gas phase line pressure reached atmospheric pressure.

Here, dichlorodibutoxytitanium (D) is added in a propylene atmosphere! t, 3 milligrams were introduced.

In the second stage polymerization, the propylene/ethylene mixing ratio was x/
to li amount ratio of the mixture at a rate of it, rp7 hours/
, for 3 hours. The polymerization temperature is 4
It is j'C.

The polymer slurry thus obtained was centrifuged to separate the polymer, which was then dried and
1 of powder was obtained.

The bulk density of this product is 0. It was ≠4211/cc.

In addition, by drying the f-liquid, the by-product amorphous ≠,
/6I obtained.

The details of the results are shown in Table 1.

Example 3~! As the polymerization additive (D), dichlorodibutoxytitanium was added to AlCl3, FeC'1B and 5I as shown in Table 1.
The same polymerization as in Example 2 was carried out except that C1q was changed, and the results shown in Table 1 were obtained.

Example 6 /) Synthesis of solid catalyst component (A) Into a 300 ml flask that was sufficiently purged with nitrogen, 0.1 mol of MgCl2 and 0.1 mol of Ti (on
u) 0.2 mol of 4 was introduced and reacted at 0°C for 2 hours to form a homogeneous solution. After the reaction was completed, the temperature was lowered to 4LO°C, then 1λ ml of methylhydropolysiloxane was added, and the reaction was allowed to proceed for 3 hours. The generated solid component is n
- Washed with hebutane.

An amount equivalent to J mmol in terms of Mg atoms was sampled from this precipitated solid and slurried in ml of n-hebutane SO. 1.0 mmol of 81 clq was added and reacted at 70°C for 2 hours. 11 After the reaction, the product was washed 3 times with 200 ml of n-hebutane.
To this, 0.1 t milliliter of 2-ethoxyethyl acetate was added, and the reaction was carried out at 0°C for 2 hours.

20 ml of TI C1q was added to this contact-treated product and reacted at 0°C for 2 hours.

After the reaction was completed, the supernatant was taken out, and the same amount of 'rtct4 was added again, followed by reaction at 0°C for 2 hours. After the reaction was completed, the solid catalyst component (A) was obtained by washing with 100 milliliters of n-heptane t times.

The composition of the solid catalyst component (A) is Ti=2. jJ weight,
Mg=20.7 weight factor.

, 2) Polymerization contents M/, j') After sufficiently replacing the inside of the stirred polymerization reactor with propylene, n-heptane jo Q milliliter, the solid catalyst/j milligram, triethylaluminum (E) J θ milligram, 107 milligrams of diphenyldimethoxysilane (C) were introduced at 9° C. under a propylene atmosphere.

In the first stage polymerization, after raising the temperature of the polymerization reactor to 7j'C,
Add 30 ml of hydrogen, add 1/30 ml of propylene,
It was introduced for 3 hours at a constant rate of 1.17 hours. After 3 hours, the introduction of propylene was stopped, and the polymerization was continued at 7°C for an additional 3 hours. After that, purge the gas phase until the gas phase pressure becomes 0.2Kg/am2G,
The temperature was lowered to 60°C.

Here, 24 milligrams of trichlorobutoxysilconi, ram (D), was introduced at 60° C. under a propylene atmosphere.

In the second stage polymerization, ethylene was charged alone at a constant rate of /A, l#/hour for i,z hours. Polymerization temperature is tooc
It is.

The polymer slurry thus obtained was centrifuged to separate the polymer, and then dried to produce /3L,
A powder of 21% was obtained.

The bulk density of this product was O9μter11/cc.

The results were as shown in Table/.

Comparative Example-λ Polymerization was carried out in the same manner as in Example t, except that trichlorobutoxyzirconium was not used as the polymerization additive (D). The details of the results were as shown in Table-/.

(1) Polymerization ratio in each step From the pressure and gas composition analysis of the gas phase in each step, calculate the amount of dissolved monomer and the amount of unreacted monomer, and calculate the amount of finido monomer and the amount of unreacted monomer. Estimate the amount of conversion of each monomer to polymer and calculate the polymerization ratio and C3/C2 for each step.
The polymer content was determined.

The amount of conversion to the polymer obtained here is the amount of polymer obtained by carrying out the first stage heavy stage and continuous polymerization separately under the same conditions as in the example and the amount of polymer obtained in the example. It was almost a match.

(2) Evaluation of physical properties The powdered polymers obtained in each example and comparative example were pelletized using an extruder under the same conditions and with the following additives. A sheet with a thickness of 4tIIJa was produced by injection molding, and the physical properties were evaluated.

((> Additive blend λ, 6 di-tert-butylphenol θ, 1 q
6Rptoto (manufactured by Ciba Geigy) θ, or
'16 Calcium Stearate o, ot% Talc 0.3 'II (
b) Various physical property values were measured using the following methods. .

MFR: ASTM-D/JJlr Conditional flexural modulus: A
STM-D7riθ Izot impact strength: ASTM-Dλ! 6 (with notch) MFRJ: MFRJ is an estimation of the MFH of the polymer produced in the process/and the overall MFR measured according to ASTM-D/23♂, which is derived from the following formula: This is a calculated value.

a log (MFR/ ) ten b log (MFR,
! ) = c log (MFRA) a: weight of polymer produced in one stage obtained by carrying out the first stage polymerization and continuous polymerization under the same polymerization conditions as in the example b = total weight obtained from the example Weight of the polymer produced in the second stage determined from the difference in weight between the polymer of MFR of the entire polymer measured in accordance with MFR/ j As TM-123g MFR of the polymer produced in one step obtained by separate polymerization.

Low crystalline polymer rigidity: (low crystalline polymer weight) / (product powder weight)

Claims (1)

[Claims] A method for producing a propylene copolymer by carrying out the following step (II) in the presence of the following catalyst (I), wherein at least the polymerization in step (2) is carried out in the presence of a halogen-containing compound. A method for producing a propylene copolymer, characterized in that the method is carried out. (I) Catalyst This catalyst consists of a combination of the following components (A) to (C). (A) A solid catalyst component containing magnesium, titanium, and halogen as essential components. (B) Organoaluminum compound (C) Electron donor (II) process This process consists of the following (1) and (2), and is a process for producing a block copolymer with a total ethylene content of 3 to 40% by weight. be. (1) A step of polymerizing propylene alone or a propylene/ethylene mixture having an ethylene content of 5% by weight or less in one or multiple stages to form a polymer in an amount corresponding to 60 to 95% by weight of the total polymerization amount. (2) A step of polymerizing a propylene/ethylene mixture having an ethylene content of 20 to 100% by weight in one or more stages.