JPS6071609A - Production of olefinic polymer - 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 method for producing olefin polymers.

More specifically, the present invention relates to a method for producing a highly crystalline propylene (co)polymer in which the amount of amorphous polymer produced is significantly reduced by using a novel solid catalyst in the polymerization or copolymerization of propylene.

Various catalyst systems have been proposed for polymerization and copolymerization of propylene. Recently, various proposals have been made regarding highly active titanium trichloride for the purpose of omitting the touch process. No. 53-111383,
JP-A No. 54-58788, etc. However, in these methods, the resulting polymer does not have sufficient crystallinity and amorphous polymers are formed in bulk, so that the extraction step cannot be omitted.

On the other hand, for the purpose of omitting the extraction step, various methods have been proposed for increasing the crystallinity of the produced polymer using polymerization additives. For example, there is Japanese Patent Application Laid-Open No. 54-118486.

However, although this method improves the crystallinity of the resulting polymer, the catalytic activity decreases and it is difficult to omit the touching step.

Therefore, the present inventors have intensively studied methods for modifying titanium trichloride with the aim of suppressing the formation of amorphous polymers while maintaining high activity. As a result, surprisingly, a titanium trichloride composition obtained by reducing titanium tetrachloride with an organoaluminum compound was contacted with an ether and an electron acceptor, and a solid obtained by further treatment with an alcohol was found. The present invention was achieved by discovering that a highly crystalline polymer can be obtained in high yield by using a catalyst composition.

That is, the present invention provides a titanium trichloride composition obtained by (2) monoreducing titanium tetrachloride with an organoaluminum compound in the polymerization of olefins, which is then treated with an ether and an electron acceptor, and further treated with an alcohol. This is a method for producing an olefin polymer, which is characterized by using a catalyst system in which a solid catalyst component is combined with (B>organoaluminum compound).

In the following, the present invention will be explained in detail, and examples of organoaluminum compounds used for reducing titanium tetrachloride include methylaluminum dichloride, ethylaluminum dichloride, n
-propylaluminum dichloride, ethylaluminum sesquichloride, dimethylaluminum chloride, diethylaluminum chloride, di-n-propylaluminum chloride, trimethylaluminum, triethylaluminum, triisobutylaluminum, diethylaluminum hydride, diethylaluminum bromide, and the like.

Among these, dialkylaluminum chloride is preferred, and specifically diethylaluminum chloride and di-n-propylaluminum chloride are used.

The reduction reaction to obtain the reduced product is carried out at a temperature range of -60 to 60°C, preferably -30 to 30°C.

The molar ratio of the organoaluminum compound and titanium tetrachloride can be freely changed depending on the purpose.

Favorable results are obtained with 0.5 to 1.5 mol of diethylaluminum chloride and 1.5 mol of ethylaluminum sesquichloride per mol of titanium tetrachloride.
~2.5 moles. Preferably, the short reduction reaction is carried out in an inert hydrocarbon solvent such as pentane, hexane, heptane, octane or decane.

The titanium trichloride composition obtained by such a reduction reaction is treated with an ether. Examples of ethers include diethyl ether, di-n-propyl ether, di-n-butyl ether, diisoamyl ether, diisoamyl ether, di-n-hexyl ether, di-n-octyl erthyl, di-2-ethyl ether, Sil ether, methyl-n-
Butyl ether isobutyl ether. Among these, di-n-butyl ether and cyinoamyl ether are preferably used.

The treatment of the titanium trichloride composition with ethers is advantageously carried out in the presence of a diluent.

As the diluent, inert hydrocarbon compounds such as hexane, heptane, octane, decane, benzene, and toluene are preferably used.

The amount of ether compound to be used is between 0.05 and 3.0 mol, preferably between 0.5 and 1.5 mol per mol of titanium trichloride.
It is a mole. The treatment temperature is preferably 0 to 100°C, and the treatment time is not particularly limited, but is usually carried out for a period of 20 minutes to 5 hours.

After ether treatment, treatment with electron acceptor is carried out,
In this case, the electron acceptors are preferably halides of elements of Groups ■ to ■ and Group ■, and specifically, titanium tetrachloride, silicon tetrachloride, boron trifluoride, boron trichloride, antimony pentachloride, Examples include gallium trichloride, iron trichloride, tellurium dichloride, tin tetrachloride, silicon tetrachloride, phosphorus trichloride, phosphorus pentachloride, vanadium tetrachloride, and zirconium tetrachloride. The most preferred is titanium tetrachloride.

The following solvents are used. Examples of aliphatic hydrocarbons include n-hebutane, n-octane, 1-octane, and the like. Examples of aliphatic hydrocarbon halides include carbon tetrachloride, dichloroethane, trichloroethylene,
Examples include tetrachlorethylene.

Examples of aromatic compounds include toluene, xylene, chlorobenzene, orthodichlorobenzene.

The concentration of the electron acceptor is usually preferably in the range of 10% by weight to 80% by weight.

The treatment temperature ranges from room temperature to 100°C, preferably from 50°C to 8°C.
Temperatures up to 0°C are chosen.

Processing times typically range from 30 minutes to 4 hours.

Further, a solid catalyst component is obtained by contact treatment with an alcohol.
, particularly preferred, and < are preferably 1 to 8 alcohols or diols, such as methanol, ethanol, n-butanol, tert-butanol, n hexanol, n-
Examples include octatool, 2-ethyl-hexanol, n-f canol, cyclohexanol, phenol, benzyl alcohol, ethylene glycol, propylene glycol, and the like. Among these, the best one is Ethanonopenn
- Aliphatic monohydric alcohols such as butanol are used.

Alcohol is 0.01 to 1 per mole of titanium trichloride.
．． 0 mol, preferably 0.02 to 0.2 mol. The treatment temperature is preferably 0 to 100°C. Although there is no particular restriction on the treatment time, 5 minutes or more is preferable.

The organoaluminum compounds used in combination with the solid catalyst component obtained as described above include dimethylaluminum chloride, diethylaluminum chloride,
Examples include di-n-propyl chloride, diisobutylaluminum chloride, diethylaluminum bromide, diethylaluminum iodide, triethylaluminum, diethylaluminium ethoxide, and among these, diethylaluminium chloride and di-n-propylaluminum chloride are particularly preferred.

Furthermore, the above-mentioned organoaluminum compound may be modified with a known electron-donating compound before use. Examples of electron-donating compounds include esters such as methyl benzoate, ethyl benzoate, and methyl methacrylate, phosphorus compounds such as triphenylphosphite and triphenylphosphine, and amines such as triethylamine and tri-n-butylamine. Note that these electron-donating compounds may be added to the polymerization tank separately from the organoaluminum compound.

The monomer used for polymerization is mainly propylene, but
Other monomers may be randomly or block copolymerized. Monomers used for copolymerization include:
Ethylene, 1-butene, 1-hexene, 4-methyl-1
-pentene, 4-methyl-1,4-hexadiene, etc. The comonomer content is usually less than 20% by weight, preferably less than 15% by weight.

The polymerization reaction can be carried out in the presence or absence of an inert solvent such as hexane, heptane, etc., ie in the presence of liquid propylene or in gas phase propylene. The polymerization reaction temperature is usually 40 to 90°C (preferably 50 to 80°C).
℃). The reaction can be carried out batchwise or continuously.

EXAMPLES Hereinafter, the present invention will be explained in more detail with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist thereof.

Example 1 Catalyst preparation 500mA with nitrogen substitution! A glass Mitsuro flask (with thermometer, dropping funnel, and stirring bar) with an internal volume of 144 m
Butane and 58 m, l of titanium tetrachloride are added to the purified solution of /. There is still 120 ml of hebutane and 66 m in the dropping funnel.
Charge 1 of diethyl aluminum chloride. The flask is cooled to -10° C. and diethylaluminum chloride is added dropwise over 3 hours with stirring at 120 rpm. After further reacting at -10°C for 1 hour, the temperature of the system was slowly raised to 65°C over 1 hour. After reacting for 1 hour at 65° C., the supernatant is separated by decantation and washed 5 times with 200 rnl of fresh purified butane. Next, 250 m/' of hebutane and 99 ml of diisoamyl ether were added and reacted at 7.35°C for 1 hour. After the reaction is complete, purified hebutane 2 is added in the same way as in the reduction of titanium tetrachloride
Wash 5 times with 00ml. Next, 150 rnl of hebutane and 116 mA of titanium tetrachloride are added and reacted at 65°C for 2 hours. After the reaction is finished, purified butane is added at 200ml/l!
Wash 5 times with Finally, 150 ml of hebutane and 2.3 mj of n-butanol were added, reacted for 1 hour at room temperature, and washed three times with 200 mj of purified hebutane to obtain a solid catalyst component.

A stainless steel autoclave with a polymerization content of W x 3 L was purged with nitrogen, and 1.5 t of purified hebutane, 1.02 t of diethylaluminum chloride, and 0.12 t of the above solid catalyst component were charged, and hydrogen was heated at a partial pressure of 0.3 Kq/ca. Prepare the quantity.

The temperature of the autoclave was then raised to 65°C, and the pressure of propylene was increased to 7 kg/crl G''4 to initiate polymerization, and the polymerization was continued for 5 hours while replenishing propylene to maintain this pressure.

After the polymerization is complete, the monomer introduction is stopped, unreacted monomers are purged, and butanol is used at 100 mA! was added to decompose the catalyst.

When the produced polymer was separated from heptane in an oven and dried, 4
83.51 polypropylene powder was obtained. 7r = When heptane was removed from the liquid by heating, an amorphous polymer 2.
32 was obtained. The proportion of amorphous polymer in the total polymer (hereinafter abbreviated as AP derivative ratio) was 0.47.

Further, the boiling n-hebutane insoluble content (hereinafter abbreviated as P-II) of the polypropylene powder was 98.1%, and the polymer yield per solid catalyst (hereinafter abbreviated as CY) was 4858. MFR (melt flow index: ASTM-
Measured according to D-1238. ) was 1.72, and the bulk specific gravity was 0.49.

Comparative Example 1 A solid catalyst component was prepared in the same manner as in Example 1, except that the n-butanol treatment at the end of catalyst preparation was not performed.

Polymerization was carried out in the same manner as in Polymerization Example 1. The result is 485
．． 11i' of polypropylene powder and 8.22 of an amorphous polymer were obtained. CY is 4933, AP derivation rate is 1.6
6%, P-II was 96.6, MFR was 2.87, and bulk specific gravity was 0.50.

As is clear from these results, while Example 1 maintains the same activity as Comparative Example 1, the derivation rate of amorphous polymer is reduced to 1/3 or less. In other words, it is clear that the generation of amorphous polymers is significantly suppressed by performing alcohol treatment at the final stage of preparing the solid catalyst component.

Examples 2 to 5 Solid catalyst components were prepared in the same manner as in Example 1, except that the type and amount of alcohol were changed in the alcohol treatment at the end of catalyst preparation.

Polymerization was carried out in the same manner as in Polymerization Example 1. Table 1 shows the results.
Shown below.

(Margin below) Table 1 Example 6 Catalyst preparation A solid catalyst component was prepared in the same manner as in Example 1.

Polymerization was carried out in the same manner as in Example 1, except that 0.83 mmol of ethyl benzoate was charged simultaneously with 1.02 mol of diethylaluminum chloride. As a result, CY is 4
163, AP derivation rate is 0.21%, P-I I is 99.
1%, MFR was 1.13, and bulk specific gravity was 0.51.

Comparative example 2 Catalyst preparation A solid catalyst component was prepared in the same manner as in Comparative Example 1.

Polymerization was carried out in the same manner as in Polymerization Example 6. As a result, C.Y.
is 3856, AP derivation rate is 0.61 chi, P-II is 98
．． 3, MFR was 1.72, and bulk specific gravity was 0.51.

Comparing Example 6 and Comparative Example 2, it is clear that Example 6 has higher activity and lower AP derivation rate.

Patent applicant Mitsubishi Yuka Co., Ltd. Agent: Patent Attorney Hidetoshi Furukawa (1 other person)

Claims (1)

[Claims] In the polymerization of olefins, (a) a solid catalyst obtained by treating a titanium trichloride composition obtained by reducing titanium tetrachloride with an organoaluminum compound with an ether and an electron acceptor, and further treating with an alcohol; component and (J3
) A method for producing an olefin polymer, characterized by using a catalyst system in combination with an organoaluminum compound.