JPS63280706A - Polymerization of propylene - Google Patents

Abstract

PURPOSE:To obtain a highly crystalline polypropylene with outstanding physical properties, by polymerization of propylene using a catalytic system consisting of an organoaluminum compound and a transition metal catalyst prepared by carrying a titanium halide on a carrier formed by a specific process. CONSTITUTION:The objective polypropylene can be obtained by polymerization of propylene using a catalytic system consisting of (A) an organoaluminum compound (e.g., trialkylaluminum, dialkylaluminum halide) and (B) a transition metal catalyst, a solid catalyst prepared by carrying a titanium halide on a carrier formed by reaction, in the presence of talc while irradiating a ultrasonic wave, between (i) a halogenated hydrocarbon compound (pref. 1-20C- hydrocarbon chloride) and (ii) a Grignard reagent (pref., a product formed by reaction between 1-20C hydrocarbon bromide or iodide and metallic magnesium in an ether-contg. solvent).

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for polymerizing propylene. Specifically, the present invention relates to a method for producing highly crystalline polypropylene using a specific catalyst.

[Conventional technology]

Polypropylene is a polymer with excellent rigidity and is used in a variety of ways. However, there is a problem in that the crystallinity of the molded product is relatively low, and the physical properties of ordinary molded products are inferior to the originally expected physical properties.

In response to this, attempts have been made to improve this by adding various nucleating agents, and molded bodies with excellent rigidity and transparency have been obtained.

[Problem that the invention seeks to solve]

The method of adding a nucleating agent is simple and effective, but it requires the addition of a relatively large amount of nucleating agent, which may cause variations in the physical properties of the molded product due to poor dispersion of the nucleating agent, or bleed of the added nucleating agent. Attempts have been made to improve this by adding specific polymer compounds, but this is not sufficient.
A more effective method is desired.

c. Means for Solving Problems] The present inventors have earnestly searched for a more effective method and have arrived at the present invention.

That is, the present invention provides a method for polymerizing propylene using a catalyst consisting of a transition metal catalyst and an organoaluminum compound, in which the transition metal catalyst is combined with a halogenated hydrocarbon compound and a Grignard reagent while irradiating ultrasonic waves in the presence of talc. This is a method for producing highly crystalline polypropylene, characterized in that the catalyst is a solid catalyst obtained by supporting a titanium halide on a carrier obtained by reacting the following.

The present invention is characterized by the transition metal catalyst used. Specifically, the present invention uses a catalyst in which titanium halide is supported on a specific carrier.

As a method for manufacturing a carrier supporting titanium halide,
It is produced by reacting a halogenated hydrocarbon compound and a Grignard reagent in the presence of talc under ultrasonic irradiation.

As the halogenated hydrocarbon compound, a chloride having 1 to 20 carbon atoms is preferable. The Grignard reagent used is one produced by reacting a halogenated hydrocarbon compound, preferably a bromide or iodide having 1 to 20 carbon atoms, and metal magnesilla in a solvent usually containing ether.

Ultrasonic irradiation does not need to be carried out constantly during the reaction between the halogenated hydrocarbon and the Grignard reagent, and may be carried out intermittently or only at the beginning of the reaction.

Talc, i.e., a hydrous silicate of magnesium (a rock usually called katsite, refined and pulverized as necessary)
is 1/1000 to 1/1 in the carrier produced by the above reaction.
2. It is preferably added in such a proportion that it accounts for about 1/100 to 1/3.

In the present invention, prior to or during the loading of titanium halide on the carrier obtained by the above reaction, an electron-donating compound, specifically an oxygen-containing compound such as ester, ether, orthoester, alkoxy silicon, etc. If the catalyst is treated with a nitrogen-containing compound such as a compound, an amine, or an amide, or a phosphorus-containing compound such as a phosphoric acid ester or a phosphorous acid ester, then when propylene is polymerized using the resulting catalyst, the steric properties of the resulting polypropylene will be reduced. It is also possible to improve the regularity or the activity of transition metal catalysts.

As the titanium halide used for supporting, at least 1
It is a titanium compound having two halogen atoms, and in particular, liquid titanium halides such as titanium tetrachloride or titanium dichloride solubilized in a hydrocarbon solvent with an electron-donating compound or the like are preferably used.

Supporting can be carried out simply by bringing the titanium halide into contact with the above-mentioned carrier, but it is preferable to disperse the carrier in liquid titanium halide under heating and carry out the contact treatment.

In the present invention, propylene is polymerized using a catalyst consisting of the above transition metal catalyst and an organoaluminum compound.

Here, as the organoaluminum compound, trialkylaluminum, dialkylaluminum halide, alkylaluminum sesquihalide, and alkylaluminum civalide can be used, and examples of the alkyl group include methyl group, ethyl group, propyl group, butyl group, and hexyl group. Examples of halides include chlorine, bromine, and iodine.

This stereoregularity improver, for example, among the compounds listed as the electron-donating compounds above, those effective for improving the stereoregularity of polypropylene during polymerization can also be used in combination, for example, usually ether Oxygen-containing compounds such as , esters, orthoesters, and alkoxy silicon compounds are preferred.

In the present invention, the polymerization of propylene can be carried out in an inert medium such as a hydrocarbon solvent such as pentane, hexane, heptane, decane, benzene, toluene, xylene, etc., or by a bulk polymerization method using propylene itself as a liquid medium, or by a bulk polymerization method using propylene itself as a liquid medium. It can also be carried out by a gas phase polymerization method in which substantially no liquid medium is present, and the polymerization temperature is from room temperature to 100° C., and the polymerization pressure is from normal pressure to 50 kg/cd gauge.

The present invention is applicable not only to the homopolymerization of propylene, but also to the copolymerization with other α-olefins such as ethylene in small amounts up to several percent, and the polymerization of ethylene or other α-olefins as necessary at the core in a later stage. It can also be applied to the production of so-called Pronk copolymers, in which copolymerization is carried out to account for 20 to 95 wt% of the copolymer.

〔Example〕

Hereinafter, the present invention will be further explained by citing examples.

Example 1 Put 1 g of talc, 16 g of carbon tetrachloride, and 50 d of diethyl ether into a 300 d flask, and add 2 g of magnesilam.
While stirring the Grignard reagent obtained from 9.5 g of methylpromide and
0 J, 45 ktlz, 30 W) for 10 minutes from the start of the reaction, and the mixture was dropped into boiling ethyl ether over 1 hour to obtain a solid component. Analysis of a portion revealed that it contained 5 wt% of talc.

Put &5g from which the solid part was separated into a 200-ml flask,
Add 50 d of titanium tetrachloride, 50 ml of toluene, and 0.8 ml of diisobutyl phthalate, stir at 110°C for 1 hour, separate by standing, remove the supernatant, and add 50 ml of titanium tetrachloride.
0-, 50 ml of toluene was added, and the mixture was stirred at 110° C., and the supernatant was separated by standing again. The solid content was then washed with n-hebutane to obtain a transition metal catalyst component.

A portion was taken out and analyzed and found to contain 3.2 wt% titanium.

20 mg of this transition metal catalyst component, 0.15+J of triethylaluminum, 0.03 rimethoxyphenylsilane
A catalyst slurry was prepared by mixing 100 rd of - and n-hebutane, and the slurry was placed in an autoclave having an internal volume of 51 kg, and 1.8 kg of propylene and 3.3 N of hydrogen were added thereto, and a polymerization reaction was carried out at 75°C for 2 hours. After the polymerization reaction, unreacted propylene was purged and the polymer was taken out at 80°C160C1.
After drying at 6O for 12 hours, 640 g of powder was obtained.

The scratch limiting viscosity (measured with a tetralin solution at 135°C, hereinafter abbreviated as η) and boiling point a! of the obtained polymer. n-
Extraction residual rate when extracted with hebutane for 6 hours using a Soxhlet extractor (hereinafter abbreviated as II. Powder weight after extraction/
The weight of the powder before extraction (expressed in 100%) was measured.

Also, some powders contain phenolic stabilizers 10/10.
000 weight ratio and calcium stearate 15/100
After adding 00 weight ratio and granulating, the melt flow index (hereinafter abbreviated as Ml) was measured. In addition, an indexine sheet having a thickness of II was made and its bending rigidity was measured.

MIAST? l D~1238 (2
30°C) Bending stiffness ASTM D-747-6
3 (20℃) Furthermore, using a differential thermal analyzer, 10''C/
The temperature was raised or lowered by sin, and the melting point and crystallization temperature were measured as the temperature showing the maximum peak.

The results are shown in the table.

Comparative Example 1 Example 1 except that a transition metal catalyst prepared in the same manner as in Example 1 was used without using talc and without irradiating ultrasonic waves.
Propylene is polymerized in the same manner as polypropylene 6.
08g was obtained. The physical properties of the obtained polypropylene were measured.

The results are shown in the table.

Comparative Example 2 30% of talc was added to the polypropylene powder obtained in Comparative Example 1.
It was added so as to have a concentration of 0 ppm, and after granulation was performed in the same manner as in Example 1, the physical properties were measured.

The results are shown in the table.

Comparative Example 3 A carrier was synthesized without irradiating ultrasonic waves, and the following Example 1
In the same manner as above, 585 g of a polymer was obtained.

Other results are shown in the table.

Example 2 A transition metal catalyst prepared in the same manner as in Example 1 was used, except that a mixture of 4 g of carbon tetrabromide and 20 g of propane chloride was used instead of 16 g of carbon tetrachloride, and 4 g of hydrogen was used during polymerization.
．． 2Nj! Propylene was polymerized in the same manner as in Example 1 except that 570 g of polypropylene was obtained. The obtained powder was evaluated in the same manner as in Example 1.

The results are shown in the table.

〔Effect of the invention〕

By implementing the method of the present invention, it is possible to produce polypropylene with excellent physical properties, and it is extremely valuable industrially.

[Brief explanation of the drawing]

FIG. 1 is a flow diagram to aid understanding of the present invention.

Claims (1)

[Claims] 1. In a method of polymerizing propylene using a catalyst consisting of a transition metal catalyst and an organoaluminum compound, the transition metal catalyst reacts with a halogenated hydrocarbon compound and a Grignard reagent while irradiating ultrasonic waves in the presence of talc. A method for producing highly crystalline polypropylene, characterized in that the solid catalyst is obtained by supporting titanium halide on the obtained carrier.