KR102038778B1 - The preparation method of solid catalyst for propylene polymerization - Google Patents

Abstract

The present invention relates to a method for manufacturing a solid catalyst for propylene polymerization. More specifically, the method comprises steps of: (1) conducting a primary reaction of dialkoxy magnesium and titanium tetrachloride in the presence of an organic solvent; (2) conducting a reaction by adding two or more non-aromatic internal electron donors to an output of the step (1); and (3) conducting a secondary reaction of an output of the step (2) with titanium tetrachloride, followed by washing an output thereof. A catalyst manufactured by the method described in the present invention can provide a propylene polymer having not only high catalytic activity but also excellent stereoregularity and high hydrogen reactivity.

Description

The preparation method of solid catalyst for propylene polymerization

The present invention relates to a method for preparing a solid catalyst for propylene polymerization, and more particularly, (1) reacting dialkoxy magnesium and titanium tetrachloride in the presence of an organic solvent in a primary manner; (2) reacting the result of step (1) by adding two or more non-aromatic internal electron donors; (3) The solid catalyst for propylene polymerization, which comprises a step of secondly reacting the resultant of step (2) with the titanium halide compound and washing the resultant, provides high catalytic activity as well as excellent stereoregularity and high It is possible to provide a propylene polymer having hydrogen reactivity.

Polypropylene is a very industrially useful material, and is widely used in various applications, particularly in materials related to automobiles and electronic products. In order to further expand the application of polypropylene, it is important to improve the rigidity by increasing the crystallinity. For this purpose, the solid catalyst for propylene polymerization should be designed to exhibit high stereoregularity.

In the polymerization of olefins such as propylene, a solid catalyst containing magnesium, titanium, an electron donor and a halogen as an essential component is known, and a olefin is obtained by using a catalyst system composed of this solid catalyst and an organoaluminum compound and an organosilicon compound. Many methods have been proposed for polymerizing or copolymerizing the solvents. However, these methods are not sufficient to obtain high stereoregular polymers in high yields and improvements are needed.

Catalyst activity is one of the most basic and important properties in the catalyst for propylene polymerization. If the activity is high, a small amount of the catalyst can be used, thereby reducing the production cost and reducing the residual amount of volatile substances such as metal catalyst residues such as magnesium, titanium, halogen, and hexane used for the catalyst injection.

As described above, in the propylene polymerization, a diester of an aromatic dicarboxylic acid is used as an internal electron donor in order to lower the cost by increasing the catalytic activity and to improve the physical properties of the polymer by improving the catalytic performance such as stereoregularity. The method is well known and patents have been filed. U.S. Patent No. 4,562,173, U.S. Patent No. 4,981,930, Korean Patent No. 0072844 and the like can be cited as examples, and these patents use an aromatic dialkyl diester or an aromatic monoalkyl monoester to form a highly active, high solid regularity. The catalyst production method which expresses is introduced.

However, diester compounds of aromatic dicarboxylic acids, such as those used in the above patents, may have adverse effects on humans and ecosystems such as infertility, growth disorders, malformations, and cancer in humans, even in very small amounts. It is known as an environmental hormone substance. Therefore, in recent years, the production of polypropylene for use in food packaging containers, etc., there is a demand for using an environmentally friendly material as an internal electron donor. In addition, the methods of the above patents are not sufficient to obtain high stereoregular polymers in high yield and require improvement.

On the other hand, in addition to the alkyl ester as described above as an internal electron donor, a catalyst using a non-aromatic diester material (Korean Patent No. 0491387) and a non-aromatic material having both a ketone and an ether functional group (Korean Patent No. 0572616) Methods are known. However, there is room for both of these methods to be greatly improved in terms of both activity and stereoregularity.

In addition, US Pat. No. 6,048,818 discloses a method for preparing a catalyst using malonate as an internal electron donor, but this method has a disadvantage in that the activity and stereoregularity are low enough to be unsuitable for commercial use. .

The present invention is to solve the problems of the prior art as described above, an object of the present invention is a solid catalyst for propylene polymerization that can produce a polypropylene excellent in stereoregularity with high yield without containing environmentally harmful substances It is to provide a method for producing.

In order to solve the above problems, the present invention provides a method for producing a solid catalyst for propylene polymerization, comprising the following steps:

(1) firstly reacting dialkoxy magnesium and titanium tetrachloride in the presence of an organic solvent;

(2) adding two kinds of non-aromatic internal electron donors to the resultant of step (1) and reacting them; And

(3) reacting the resultant of step (2) with titanium tetrachloride secondly, and washing the resultant.

As the organic solvent used in the step (1), there is no particular limitation on the kind, and aliphatic hydrocarbons, aromatic hydrocarbons and halogenated hydrocarbons having 6 to 12 carbon atoms may be used, and more preferably saturated aliphatic having 7 to 10 carbon atoms. Or aromatic hydrocarbons, halogenated hydrocarbons may be used, and specific examples thereof may be used alone or in combination of one or more selected from octane, nonane, decane, toluene and xylene, chlorobutane, chlorohexane, chloroheptane and the like.

As the dialkoxy magnesium used in the step (1), diethoxy magnesium may be particularly preferably used. The dialkoxy magnesium has an average particle diameter of 10 to 200 µm obtained by reacting metal magnesium with anhydrous alcohol in the presence of a reaction initiator such as magnesium chloride, and the surface is smooth spherical particles. Although it is preferable to maintain it as it is, when the said average particle diameter is less than 10 micrometers, it is unpreferable because the fine particle of the manufactured catalyst increases, and when it exceeds 200 micrometers, the apparent density tends to become small and it is not preferable.

The reaction in step (1) of the solid catalyst production process is preferably carried out by slowly adding titanium tetrachloride in a state in which the dialkoxy magnesium is suspended in an organic solvent in the temperature range of 0 ~ 30 ℃.

The amount of titanium tetrachloride used in step (1) is preferably 0.1 to 10 moles, more preferably 0.3 to 2 moles per 1 mole of dialkoxymagnesium. If less than 0.1 mole, the reaction of dialkoxy magnesium to magnesium chloride is reduced. It is not preferable because it does not proceed smoothly, and exceeding 10 moles is not preferable because excessively many titanium components are present in the catalyst.

In the process for producing a solid catalyst for propylene polymerization, the non-aromatic internal electron donor used in the step (2) may be represented by the following general formulas (I) and (II).

The non-aromatic internal electron donor is represented by the following general formula (I), and specific examples thereof include dimethyl cyclohexa-1,4-diene-1,2-dicarboxylate (dimethyl cyclohexa-1,4-diene-1 , 2-dicarboxylate), diethylcyclohexa-1,4-diene-1,2-dicarboxylate (diethyl cyclohexa-1,4-diene-1,2-dicarboxylate), dipropylcyclohexa-1,4- Diene-1,2-dicarboxylate (dipropyl cyclohexa-1,4-diene-1,2-dicarboxylate), diisopropylcyclohexa-1,4-diene-1,2-dicarboxylate (diisopropyl cyclohexa-1) , 4-diene-1,2-dicarboxylate), dibutylcyclohexa-1,4-diene-1,2-dicarboxylate (dibutyl cyclohexa-1,4-diene-1,2-dicarboxylate), diisobutyl Diisobutyl cyclohexa-1,4-diene-1,2-dicarboxylate, dipentylcyclohexa-1,4-diene-1,2-dicarboxyl Dipentyl cyclohexa-1,4-diene-1,2-dicarboxylate, diisopentylcyclohexa-1,4-diene-1,2-dicarboxylate (Diisopentyl cyclohexa-1,4-diene-1,2-dicarboxylate), dihexylcyclohexa-1,4-diene-1,2-dicarboxylate (dihexyl cyclohexa-1,4-diene-1,2- dicarboxylate), dioctylcyclohexa-1,4-diene-1,2-dicarboxylate, and the like.

‥‥‥ (I)

‥‥‥ (I)

Wherein R ₁ and R ₂ are linear or branched alkyl groups of 1 to 20 carbon atoms or cyclic alkyl groups of 3 to 6 carbon atoms.

The non-aromatic internal electron donor is represented by the following general formula (II), and specific examples thereof include dimethyl adipate, diethyl adipate, dipropyl adipate, and diiso. Diisopropyl adipate, dibutyl adipate, diisobutyl adipate, dipentyl adipate, dipentyl adipate, diisopentyl adipate, dihexyl adipate (dihexyl adipate), dioctyl adipate, and the like.

‥‥‥ (II)

‥‥‥ (II)

Wherein R ₁ and R ₂ are linear or branched alkyl groups of 1 to 20 carbon atoms or cyclic alkyl groups of 3 to 6 carbon atoms.

The step (2) is preferably carried out by slowly increasing the temperature of the resultant of the step (1) to 80 ~ 130 ℃, by reacting for 1 to 3 hours by adding the internal electron donor during the temperature increase process, If the temperature is less than 80 ° C. or the reaction time is less than 1 hour, the reaction is difficult to complete. If the temperature exceeds 130 ° C. or the reaction time is more than 3 hours, side reactions may lower the polymerization activity of the resulting catalyst or the stereoregularity of the polymer. have.

As long as the internal electron donor is added during the temperature raising process, the temperature and the number of the inputs are not particularly limited, and the total amount of the internal electron donor is 0.1 to 1.0 mole based on 1 mole of dialkoxy magnesium used. It is preferable that outside the above range, the polymerization activity of the resulting catalyst or the stereoregularity of the polymer may be lowered.

In the solid catalyst production process, step (3) is a step of secondary reaction and washing the product of the step (2) and titanium tetrachloride, it is preferably carried out at a temperature of 80 ~ 130 ℃.

By using the solid catalyst for propylene polymerization prepared by the method of the present invention, it is possible to produce polypropylene having high catalytic activity, stereoregularity and hydrogen reactivity with high yield without containing environmentally harmful substances.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, these embodiments are for illustrative purposes only.  The invention is not limited to these examples.

EXAMPLE

Example 1

[Production of Solid Catalyst]

150 ml of toluene and 20 g of diethoxy magnesium having an average particle size of 20 µm were added to a glass reactor equipped with a 1 liter stirrer sufficiently substituted with nitrogen, and maintained at 10 ° C. 40 ml of titanium tetrachloride was added over 1 hour, and then the temperature of the reactor was raised to 110 ° C. while diethyl cyclohexa-1,4-diene-1,2-dicarboxylate (diethyl cyclohexa-1,4-diene-1) was added. , 2-dicarboxylate) and 11.2 mmol of diethyl adipate were injected. After holding at 110 ° C. for 2 hours, the temperature was lowered to 90 ° C. to stop stirring, the supernatant was removed, and further washed once using the same method using 200 ml of toluene.

150 ml of toluene and 50 ml of titanium tetrachloride were added thereto, and the temperature was raised to 110 ° C. and maintained for 2 hours. After completion of the aging process, the slurry mixture was washed twice with 200 ml of toluene per second, and washed five times with 200 ml each time with normal hexane at 40 ° C. to obtain a pale yellow solid catalyst component.

[Polypropylene Polymerization]

10 mg of the solid catalyst, 6.6 mmol of triethylaluminum, and 0.66 mmol of dicyclopentyldimethoxysilane were charged into a 4 liter high pressure stainless reactor. Subsequently, 1000 ml of hydrogen and 2.4 L of propylene in a liquid state were sequentially added, and then the temperature was raised to 70 ° C. for polymerization. After 2 hours after the start of the polymerization, the valve was opened while lowering the temperature of the reactor to room temperature to completely remove propylene in the reactor. The analysis results of the obtained propylene polymer are shown in Table 1.

Here, catalytic activity and stereoregularity were determined by the following method.

1.catalytic activity (kg-PP / g-catalyst) = amount of polypropylene produced (kg) ÷ amount of catalyst injected (g)

2. Stereoregularity (X.I.): In 100% of the polymer, the weight% of the insoluble component precipitated by crystallization in mixed xylene

3. Hydrogen Reactivity (MFR): The polymer was melted at 230 ° C. and then flowed for 10 minutes by pressing with a weight of 2.16 kg (ISO 1133).

Example 2

[Preparation of a solid catalyst] of Example 1, diethyl cyclohexa-1,4-diene-1,2-dicarboxylate (diethyl cyclohexa-1,4-diene-1,2-dicarboxylate) 11.2 Example 1 except that 11.2 mmol of dibutyl cyclohexa-1,4-diene-1,2-dicarboxylate was used instead of mmol. In the same manner a solid catalyst was prepared. Thereafter, polypropylene polymerization was carried out in the same manner as in Example 1, and the analysis results of the obtained propylene polymer are shown in Table 1.

Example 3

[Preparation of solid catalyst] of Example 1, diethyl cyclohexa-1,4-diene-1,2-dicarboxylate (diethyl cyclohexa-1,4-diene-1,2-dicarboxylate) 11.2 Example 1, except that 11.2 mmol of diisobutyl cyclohexa-1,4-diene-1,2-dicarboxylate was used instead of mmol In the same manner as the solid catalyst was prepared. Thereafter, polypropylene polymerization was carried out in the same manner as in Example 1, and the analysis results of the obtained propylene polymer are shown in Table 1.

Comparative Example 1

[Preparation of solid catalyst] of Example 1, diethyl cyclohexa-1,4-diene-1,2-dicarboxylate (diethyl cyclohexa-1,4-diene-1,2-dicarboxylate) 11.2 A solid catalyst was prepared in the same manner as in Example 1, except that 22.4 mmol of diisobutyl phthalate was used instead of 11.2 mmol of mmol and diethyl adipate. Thereafter, polypropylene polymerization was carried out in the same manner as in Example 1, and the analysis results of the obtained propylene polymer are shown in Table 1.

Comparative Example 2

[Preparation of solid catalyst] of Example 1, diethyl cyclohexa-1,4-diene-1,2-dicarboxylate (diethyl cyclohexa-1,4-diene-1,2-dicarboxylate) 11.2 The catalyst was prepared in the same manner as in Example 1, except that 22.4 mmol of diethyl 2,3-diisopropylsuccinate was used instead of 11.2 mmol of mmol and diethyl adipate. Prepared. Thereafter, polypropylene polymerization was carried out in the same manner as in Example 1, and the analysis results of the obtained propylene polymer are shown in Table 1.

Comparative Example 3

[Preparation of solid catalyst] of Example 1, diethyl cyclohexa-1,4-diene-1,2-dicarboxylate (diethyl cyclohexa-1,4-diene-1,2-dicarboxylate) 11.2 22.4 mmol of diethyl 9,9-bis (methoxymethyl) -9H-fluorene instead of mmol and 11.2 mmol of diethyl adipate Except that, a catalyst was prepared in the same manner as in Example 1. Thereafter, polypropylene polymerization was carried out in the same manner as in Example 1, and the analysis results of the obtained propylene polymer are shown in Table 1.

Comparative Example 4

[Preparation of solid catalyst] of Example 1, diethyl cyclohexa-1,4-diene-1,2-dicarboxylate (diethyl cyclohexa-1,4-diene-1,2-dicarboxylate) 11.2 22.4 mmol of diethyl cyclohexa-1,4-diene-1,2-dicarboxylate instead of mmol and diethyl adipate 11.2 mmol A catalyst was prepared in the same manner as in Example 1 except for using. Thereafter, polypropylene polymerization was carried out in the same manner as in Example 1, and the analysis results of the obtained propylene polymer are shown in Table 1.

Comparative Example 5

[Preparation of solid catalyst] of Example 1, diethyl cyclohexa-1,4-diene-1,2-dicarboxylate (diethyl cyclohexa-1,4-diene-1,2-dicarboxylate) 11.2 A catalyst was prepared in the same manner as in Example 1, except that 22.4 mmol of diethyl adipate was used instead of 11.2 mmol of mmol and diethyl adipate. Thereafter, polypropylene polymerization was carried out in the same manner as in Example 1, and the analysis results of the obtained propylene polymer are shown in Table 1.

division Internal electron donor activation
(kg-PP / g-catalyst) Stereoregularity
(XI, weight percent) Hydrogen reactivity
(MFR, g / 10 min) Example # 1 Diethylcyclohexa-1,4-diene-1,2-dicarboxylate / diethyl adipate 78 98.5 4.7 Example # 2 Dibutylcyclohexa-1,4-diene-1,2-dicarboxylate / diethyl adipate 71 98.6 4.5 Example # 3 Diisobutylcyclohexa-1,4-diene-1,2-dicarboxylate / diethyl adipate 72 98.4 5.1 Comparative Example 1 Diisobutyl phthalate 64 98.1 1.9 Comparative Example 2 Diethyl 2,3-diisopropylsuccinate 44 98.3 0.4 Comparative Example 3 Diethyl 9,9-bis (methoxymethyl) -9H-fluorene 50 98.0 3.4 Comparative Example 4 Diethylcyclohexa-1,4-diene-1,2-dicarboxylate 65 98.2 2.1

As shown in Table 1, cyclohexa-1,4-diene-1,2-dicarboxylate and diethyl adipate according to the present invention. Examples 1 to 3 using two kinds of internal electron donors, i.e., aromatic dialkyl esters (diisobutyl phthalate), non-aromatic dialkyl esters (diethyl 2,3-diisopropylsuccinate) or diethers (diethyl 9,9-bis (methoxymethyl) Comparative Examples 1 to 3 using a 9-9-fluorene internal electron donor and diethyl cyclohexa-1,4-diene-1,2-dicarboxylate Compared to Comparative Example 4 using only), not only the catalytic activity and the stereoregularity was high, but also the hydrogen reactivity was greatly improved.

Claims (4)

A process for preparing a solid catalyst for propylene polymerization, comprising the following steps:
(1) reacting dialkoxy magnesium and titanium tetrachloride in the presence of an organic solvent;
(2) reacting two kinds of non-aromatic internal electron donors represented by the following general formulas (I) and (II) with the result of step (1);

‥‥‥ (I)

‥‥‥ (II)
Wherein R ₁ and R ₂ are linear or branched alkyl groups of 1 to 20 carbon atoms or cyclic alkyl groups of 3 to 6 carbon atoms.
(3) reacting the product of step (2) with titanium tetrachloride.

The process for producing a solid catalyst for propylene polymerization according to claim 1, wherein the dialkoxy magnesium compound is diethoxy magnesium. A non-aromatic internal electron donor represented by the general formula (I) according to claim 1, wherein dimethylcyclohexa-1,4-diene-1,2-dicarboxylate, diethylcyclohexa-1,4-diene -1,2-dicarboxylate, dipropylcyclohexa-1,4-diene-1,2-dicarboxylate, diisopropylcyclohexa-1,4-diene-1,2-dicarboxylate, dibutyl Cyclohexa-1,4-diene-1,2-dicarboxylate, diisobutylcyclohexa-1,4-diene-1,2-dicarboxylate, dipentylcyclohexa-1,4-diene-1, 2-dicarboxylate, diisopentylcyclohexa-1,4-diene-1,2-dicarboxylate, dihexylcyclohexa-1,4-diene-1,2-dicarboxylate, dioctylcyclohexa- A process for producing a solid catalyst for propylene polymerization, characterized in that any one selected from 1,4-diene-1,2-dicarboxylate. A non-aromatic internal electron donor represented by the general formula (II), wherein the dimethyl adipate, diethyl adipate, dipropyl adipate, diisopropyl adipate, dibutyl adipate, diisobutyl Process for producing a solid catalyst for propylene polymerization, characterized in that any one selected from adipate, dipentyl adipate, diisopentyl adipate, dihexyl adipate, dioctyl adipate.