JPH0641229A - Production of olefin polymer - Google Patents

Abstract

PURPOSE:To produce an olefin polymer excellent in stiffness and clarity. CONSTITUTION:A hydrocarbon having at least two terminal nonconjugated double bonds or a mixture thereof with a 3C or higher olefin is preliminarily polymerized in the presence of a catalyst comprising a solid catalyst component essentially contg. titanium and a halogen, an organometallic compd. of a metal selected from the group consisting of metals of groups I-III of the periodic table, and/or an electron-donating compd. Then, the (co)polymn. of a 3C or higher olefin is conducted.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a polymer of an olefin. More specifically, the present invention relates to a method for producing an olefin polymer having improved transparency and rigidity using a transition metal catalyst.

[0002]

2. Description of the Related Art Crystalline olefin polymers such as polypropylene are used in the fields of injection molding and films since they have excellent properties, especially rigidity and transparency. These performances are sensitive to the crystallization behavior of the polymer. However, in order to increase the degree of crystallinity and rigidity, or to accelerate the generation of nuclei and enhance transparency, a crystal nucleating agent has been conventionally blended. For example, there are nucleating agents such as aluminum salts of aromatic carboxylic acids (Japanese Patent Publication No. 40-1652) and benzylidene sorbitol (Japanese Patent Publication No. 51-22740). However, compounding of the nucleating agent not only leads to an increase in cost, but is also easily affected by dispersion, and sufficient performance is not exhibited unless finely dispersed. Further, in order to improve without using a nucleating agent, a method of polymerizing vinylcyclohexane in the first stage (JP-A-60-139710) and the like have been proposed, but not only the polymerization activity is lowered, but also gel, fish, etc. Easy to cause eye.

[0003]

In view of the above problems, an object of the present invention is to provide a method for producing a crystalline olefin polymer having improved rigidity and transparency by improving the crystallinity in the polyolefin production step. To provide.

[0004]

Means for Solving the Problems As a result of intensive studies on these problems, the present inventors have succeeded in preliminarily polymerizing an extremely small amount of a hydrocarbon having two or more non-conjugated terminal double bonds. , The crystallization rate of olefin polymer is significantly increased,
At the same time, it was found that these rigidity and transparency were improved, which led to the present invention. That is, an object of the present invention is to provide a solid catalyst component (A) containing titanium and halogen as essential components, an organometallic compound (B) of a metal of Group I to III of the periodic table, and / or an electron donating compound (C). A hydrocarbon (D) having two or more terminal non-conjugated double bonds in the presence of a catalyst consisting of 3 or more prepolymerized as a mixture with an olefin having 3 or more carbon atoms, and then an olefin having 3 or more carbon atoms. It can be solved by a method for producing an olefin polymer, which comprises polymerizing or copolymerizing

The present invention will be described in detail below. The solid catalyst (A) used in the present invention is not particularly limited as long as it is usually used for olefin polymerization.
For example: 1) It is possible to provide a solid catalyst containing titanium trichloride as a main component. This is obtained by reducing titanium tetrachloride with metallic aluminum, hydrogen or an organic aluminum compound, or by subjecting these to contact treatment with an electron donating compound, co-milling treatment, or further treating this with titanium tetrachloride. What was done can be used. Examples of the electron-donating compound include ethers, thioethers, ketones, carboxylic acid esters, amines, carboxylic acid amides and polysiloxanes. Of these, ethers, thioethers, and carboxylic acid esters are particularly preferable. As a more specific method for preparing a solid catalyst containing titanium trichloride as a main component, for example, (a) a liquid material containing titanium trichloride liquefied in the presence of ether or thioether, a temperature of 150 ° C. or lower The method of precipitation. (B) A method in which a solid obtained by reducing titanium tetrachloride with an organic aluminum compound or metallic aluminum is treated with an electron donating compound and a halogen compound. Can be given.

2) A supported catalyst component carrying a titanium compound can be provided. This is silica, alumina,
Examples thereof include boron oxide, magnesium oxide, magnesium halide, and the like, on which titanium tetrachloride or a titanium trichloride composition is supported or chemically bonded. Of these, magnesium halide is preferably used as a carrier. As a titanium compound, Ti (O
R) A compound represented by nXm can be used.
(R is an alkyl group, X is a halogen, n and m are numbers, and have a relationship of n + m = 4.) Specifically, TiCl ₄ , TiCl ₃ , TiBr ₄ , TiI ₄ , and Ti.
(OCH ₃ ) Cl ₃ , Ti (OC ₂ H ₅ ) Cl ₃ , Ti
(OC ₄ H ₉ ) Cl ₃ , Ti (OC ₆ H ₅ ) Cl ₃ , T
i (OCH ₃ ) ₂ Cl ₂ , Ti (OC ₂ H ₅ ) ₂ Cl
₂ , Ti (OC ₄ H ₉ ) ₂ Cl ₂ , Ti (OC ₆ H ₅ ) ₂
Cl ₂ , Ti (OCH ₃ ) ₃ Cl, Ti (OC ₂ H
₅ ) ₃ Cl, Ti (OC ₄ H ₉ ) ₃ Cl, Ti (OC ₆
H ₅ ) ₃ Cl, Ti (OCH ₃ ) ₄ , Ti (OC ₂ H
₅ ) ₄ , Ti (OC ₄ H ₉ ) ₄ , Ti (OC ₆ H ₅ ) ₄
Etc. can be given. An electron donating compound can be added as another component. Examples of the electron donating compound include alcohols, ethers, esters, ketones, acid anhydrides and the like. Preferably, ethyl acetate, methyl propylene acid, ethyl acrylate, ethyl oleate, ethyl stearate, ethyl phenylacetate,
Methyl benzoate, ethyl benzoate, propyl benzoate,
Butyl benzoate, methyl toluate, ethyl toluate, propyl toluate, butyl toluate, methyl ethyl benzoate, ethyl ethyl benzoate, ethyl anisate, methyl anisate, ethyl cinnamate, diethyl phthalate, dipropyl phthalate Carboxylic acid esters such as dibutyl phthalate, diisobutyl phthalate, dipentyl phthalate, dihexyl phthalate, and dioctyl phthalate. The composition of the titanium-containing solid catalyst component,
The titanium content is 0.1 to 10% by weight, the magnesium content is 1 to 20% by weight, and the electron donating compound / titanium molar ratio is 0.1.
1 to 5, titanium / magnesium (molar ratio) is 0.01 to
0.5 is desirable. The preparation method is not particularly limited,
For example, (a) a method of co-milling a titanium compound, a carrier, and an electron-donating compound. (B) a carrier component such as magnesium chloride is solubilized by complexing with an alcohol or the like, and then a precipitate is formed with a halogenating agent. Method of treating with titanium compound (c) Method of emulsifying and suspending alcohol solution of carrier component such as magnesium chloride and then solidifying, or method of preparing carrier by spray drying and then treating with titanium compound. . Preferably, methods (b), (c), etc. are desirable for adjusting the powder properties of the polymer.

The organometallic compound (B) of a metal of Groups I to III of the Periodic Table is preferably represented by the general formula AlRnX.
Examples thereof include compounds represented by m 1. (R is an alkyl group,
X means halogen, and n and m mean the number. n +
There is a relationship of m = 3. ) Specifically, triethylaluminum, tripropylaluminum, tributylaluminum, trihexylaluminum, trioctylaluminum, diethylaluminum chloride, ethylaluminum dichloride and the like can be mentioned, but for the magnesium-supported solid catalyst, triethylaluminum is preferable, Diethylaluminum is preferred for the titanium trichloride-type solid catalyst.

In the polymerization, an electron donating compound (C) can be used if necessary. The electron-donating compound can be selected from the electron-donating compounds used in the production of the solid catalyst component, but is preferably Si-
They are silicon compounds having an OC bond and aromatic carboxylic acid ester.

The hydrocarbon (D) having a plurality of non-conjugated terminal double bonds is not particularly limited, but has 5 to 1 carbon atoms.
60 dienes or polyenes are effective. If the molecule is larger than this, the prepolymerization does not proceed sufficiently, and it is often difficult in the polymerization process. Preferably 5 to 80
And the molecular weight is 1000 or less. Double bonds must be unconjugated. The number is required to be 2 or more, but it is related to the size of the molecule, and the number of double bonds per 20 carbon atoms is 1 or more, preferably the number of double bonds per 10 carbon atoms. Is one or more. Specifically, the following hydrocarbons are included. 1,4-pentadiene, 1,5-hexadiene, 1,6-heptadiene,
1,7-octadiene, 1,8-nonadiene, 1,9-
Α, ω such as decadiene, 1,13-tetradecadiene, 2-methyl-1,4-pentadiene, 2-methyl-1,5-hexadiene, 3-methyl-1,5-hexadiene
-Dienes, 3-vinyl-1,6-heptadiene, 3-
Α, ω-dienes having a branch containing a terminal double bond on a straight chain such as allyl-1,6-heptadiene, 1,4-divinylcyclohexadiene, 1,3-divinylcyclohexane, 1,3,5- Examples include non-conjugated polyenes having a cyclic alkyl chain such as trivinylcyclohexane, and multimers of butadiene having 8 to 160 carbon atoms as shown in the following formula (1).

[Chemical 2] R means an alkyl group or hydrogen. n and m are integers.

The prepolymerization may be carried out by copolymerizing the non-conjugated double bond-containing hydrocarbon (D) alone or with an olefin. The method of prepolymerization is not particularly limited, and a reaction vessel may be provided separately from the polymerization reactor so that the entire amount of the catalyst used in advance may be treated at one time, or it may be used for continuous production that is generally performed commercially. In addition, it is also possible to provide a reactor dedicated to prepolymerization before the main polymerization reactor for processing. The polymerization temperature is not particularly limited, but 20 to 100 ° C is a suitable temperature. The amount of prepolymerization may be 0.01 wtppm to 5 wt% in the final polymer, and preferably 0.01 wtppm to 1 wt%. If it is less than 0.01 weight ppm, the effect is not clear, and if it is more than 5 weight%, the properties of the olefin polymer itself are changed.

[0011]

EXAMPLES Next, the present invention will be specifically described by way of examples. However, the present invention is not limited by these examples. The catalyst activity is the amount of polymer produced (g) per 1 hour of polymerization per 1 g of the solid catalyst component.
It is represented by. MFR was measured according to JIS-K-6721. The flexural modulus was measured according to ASTM-D-790-66. Clarity was measured with a clarity meter manufactured by Murakami Color Research Laboratory. The crystallization rate was expressed as the time (second) until the measured value of crystallinity by X-ray reached 30% after the press sample was once melted at 190 ° C. and then rapidly cooled to 125 ° C. for recrystallization. The crystallization temperature is a DSC measurement result.

Example 1 (1) Preparation of solid catalyst component (A) 7 g of Mg (OEt) ₂ , 2.1 g of n-butyl phthalate, 35 ml of methylene chloride were stirred in a 300 ml flask to give 1 After refluxing for a while, Ti
Add 100 ml of Cl ₄ dropwise over 30 minutes and then add 100 ° C.
The temperature was raised to. After reacting at 100 ° C. for 2 hours, the mixture was cooled to room temperature, only the precipitate was separated by filtration, and this was thoroughly washed with n-hexane. In addition to this precipitate TiCl ₄ 100m
1 was added and reacted at 100 ° C. for 2 hours, then cooled to room temperature, only the precipitate was filtered off, washed sufficiently with n-hexane and dried to obtain a solid catalyst component (A). (2) Preliminary Polymerization 100 mg of the solid catalyst component (A) obtained in (1), 25 mmol of triethylaluminum, 7.5 mmol of diisopropyldimethoxysilane, 150 m of dry hexane.
1, 1,9 decadiene 500 mg was mixed in a 100 ml flask and contacted at 20 ° C. for 30 minutes. Then, it was washed 3 times with 100 ml of dry hexane. A portion was taken out and analyzed for the amount of preliminary polymerization, and it was found to be 0.1% by weight per catalyst. (3) Polymerization of propylene 40 m of prepolymerized solid catalyst component obtained in (2)
g, triethylaluminum 10 mmol, diisopropyldimethoxysilane 3 mmol, dry hexane 30 m
l and liquid propylene 32 mol, hydrogen gas 1 kg / cm
² was placed in a 6 L autoclave and polymerized at 70 ° C. for 1 hour. The catalytic activity is 15,000 g-PP / g-ca
It was t. The MFR of the obtained polymer was 8. (4) Measurement of flexural modulus of polymer and evaluation of transparency 0.08 wt% of BHT (2,6-di-t-butyl-p-cresol) was added to the polymer obtained in (3), Irganox 1010 (trade name; manufactured by Nippon Ciba Geigy)
05 wt% and calcium stearate 0.1 wt% were added and kneading was carried out at 230 ° C. by a 20 mm extruder. Next, a small injection molding machine made by Sumitomo Heavy Industries (Mini mat 8
/ 7), a test piece was prepared and the flexural modulus and the transparency were evaluated. Flexural modulus is 14,200 kg / c
It was m ² . Clarity was 10.0%. The measurement results are summarized in Table 1.

Example 2 In Examples 1- (2) and (3), 40 mg of the solid catalyst was withdrawn as a slurry without washing after prepolymerization, and the polymerization was carried out by directly supplying propylene and hydrogen. Was performed in the same manner as in Example 1. Polymerization activity is 1
6,000 g-PP / g-cat, MFR was 8. The flexural modulus was 14,700 kg / cm ² .
Clarity was 10.0%. The measurement results are summarized in Table 1.

Example 3 Instead of 1,9-decadiene in Example 2, a butadiene oligomer (B-700 manufactured by Nippon Oil Co., Ltd .; an average molecular weight of 70) was used.
0) was used in the same manner as in Example 2 except that 500 mg was used. Polymerization activity is 13,000 g-PP / g-cat,
The MFR was 8. Flexural modulus is 14,000 kg /
It was cm ² . Clarity was 10%. The measurement results are summarized in Table 1.

Comparative Example 1 Without using 1,9-decadiene in Example 1, 100 mg of solid catalyst component (A), 25 mmol of triethylaluminum, 7.5 mmol of diisopropyldimethoxysilane,
The same procedure as in Example 1 was carried out except that 150 ml of dry hexane was contacted with the slurry, and immediately thereafter, a slurry of 40 mg of the solid catalyst component was extracted and subjected to polymerization. The activity is 16,000
0g-PP / g-cat, MFR was 8. The flexural modulus was 12,500 kg / cm ² . Clarity was 5%. The measurement results are summarized in Table 1.

[0016]

[Table 1]

[0017]

According to the present invention, it is possible to effectively improve the crystallinity of an olefin-based polymer and provide an injection-molded product and a film-molded product which are excellent in rigidity and transparency.

Claims (4)

[Claims] 1. A solid catalyst component (A) containing titanium and halogen as essential components, an organometallic compound (B) of a metal of Groups I to III of the Periodic Table, and / or an electron donating compound (C). Two terminal non-conjugated double bonds in the presence of a catalyst
A single hydrocarbon having 3 or more hydrocarbons (D) or 3 carbon atoms
A method for producing an olefin polymer, characterized by preliminarily polymerizing as a mixture with the above olefin, and then polymerizing or copolymerizing an olefin having 3 or more carbon atoms. 2. The amount of prepolymer relative to the final polymer is 0.
The method according to claim 1, which is from 01 ppm by weight to 5% by weight. 3. The method according to claim 2, wherein the hydrocarbon (D) having a terminal non-conjugated double bond is a diene having both ends having 5 to 20 carbon atoms. 4. The method according to claim 2, wherein the hydrocarbon (D) having a terminal non-conjugated double bond is a multimer of butadiene having 8 to 160 carbon atoms represented by the following formula (1). [Chemical 1] R means an alkyl group or hydrogen. n and m are integers.