JPS633010A - Catalyst for polymerization of olefin - Google Patents

Abstract

PURPOSE:To obtain the titled catalyst giving a polymer having high stereoregularity and bulk density without deashing, by compounding an Si compound and an organic Al compound to a component consisting of an Mg compound, an aromatic dicarboxylic acid diester, an aromatic hydrocarbon and a Ti compound. CONSTITUTION:The objective catalyst for the polymerization of an olefin can be produced by compounding (A) a catalyst component produced by contacting (i) a magnesium dialkoxide, (ii) an aromatic dicarboxylic acid diester, (iii) an aromatic hydrocarbon and (iv) a titanium halide and heat-treating the product in powdery state, (B) a silicon compound of formula (R is H, alkyl or aryl; R' is alkyl or aryl; 0<=m<=4) and (C) an organic aluminum compound.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention produces stereoregular polymers that act with high activity and have a uniform particle size distribution in extremely high yields when subjected to the polymerization of olefins. The high-performance catalyst that can be obtained is more specifically obtained by heat-treating a product obtained by contacting dialkoxymagnesium, a diester of an aromatic dicarboxylic acid, an aromatic hydrocarbon, and a titanium halide in a powder state. The present invention relates to a catalyst for olefin polymerization comprising a catalyst component for olefin polymerization, a silicon compound, and an organoaluminum compound.

[Conventional technology]

Conventionally, as a highly active catalyst for polymerizing olefins, a combination of a solid titanium halide and an organoaluminum compound as a catalyst component is well known and widely used. Since the yield of polymer per titanium (hereinafter referred to as the catalyst component and the polymerization activity per titanium in the catalyst component) is low, a so-called demineralization step to remove catalyst residues has been unavoidable. This deashing process uses a large amount of alcohol or chelating agent, so recovery equipment or regeneration equipment is essential, and there are many problems related to resources, energy, etc.
For those skilled in the art, this was an important issue that needed to be solved as soon as possible. In order to eliminate this complicated deashing step, many studies have been made and proposals have been made to increase the polymerization activity per titanium in the catalyst component, especially in the catalyst component.

In particular, there has been a recent trend in which transition metal compounds such as titanium halides, which are active ingredients, are supported on carrier materials such as magnesium chloride, and when used in the polymerization of olefins, the polymerization activity of titanium in the catalyst component is dramatically increased. There are many proposals to raise the standard.

[Problem that the invention seeks to solve]

However, does the chlorine contained in magnesium chloride, which is the main carrier material, have a negative effect on the produced polymer, similar to the halogen element in titanium halides? This leaves unresolved issues such as requiring high activity to the extent that the influence of chlorine can be virtually ignored, or the need to keep the concentration of magnesium chloride itself low. was.

The present inventors have developed a patent application filed in Japanese Patent Application No. 1983-1982 with the aim of reducing residual chlorine in the produced polymer while maintaining a high degree of polymerization activity and stereoregular polymer yield per catalyst component.
No. 200454, we proposed a method for producing a catalyst component for olefin polymerization, and achieved the intended purpose. Furthermore, when polymerizing olefins, especially stereoregular polymerization of propylene, 1-butene, etc., is carried out industrially, it is common to coexist an electron-donating compound such as an aromatic carboxylic acid ester in the polymerization system. It is essential for catalysts that use a catalyst component having a carrier as a carrier in combination with an organoaluminum compound. However, this aromatic carboxylic acid ester imparts a characteristic ester odor to the produced polymer, and its removal has become a major problem in the industry.

In addition, in so-called highly active supported catalysts, such as catalysts using catalyst components using magnesium chloride as a carrier,
Although the activity is high at the initial stage of polymerization, the deactivation is large, which poses problems in process operation, and it is almost impossible to use it in practical situations such as block copolymerization, where a longer polymerization time is required. . In order to improve this point, for example, in JP-A No. 54-94590, a catalyst component is prepared using magnesium dihalide as a starting material, and an organic aluminum compound, an organic carbo/acid ester, an M-
A method for polymerizing olefins in combination with a compound having an 0-R group has been demonstrated, but since organic carboxylic acid esters are not used during polymerization, the problem of odor of the resulting polymer has not been solved. In addition, as can be seen from the examples, very complicated operations are required, and it cannot be said that practically sufficient results have been obtained in terms of performance and alpha activity.

In addition, in industrial polymerization equipment, it is sometimes necessary to feed the catalyst into a high temperature polymerization tank, and conventional supported catalysts have significantly higher performance in such cases, especially in terms of activity, stereoregularity, and bulk specific gravity. It is known that there is a decrease in This is a major problem, especially in so-called continuous slurry polymerization using organic solvents, and there has been a strong demand for improvement in this field.

The present inventors have arrived at the present invention as a result of intensive research in order to solve the problems remaining in the prior art, and propose it to mosquitoes.

(c) Means to resolve the problem] That is, the features of the present invention are as follows: Catalyst component obtained by heat-treating a product obtained by contacting a halide in a powder state; (It) - general formula SiRm(OR"), -m (in the formula
p is hydrogen, an alkyl group or an aryl group, R/ is an alkyl group or an aryl group, and m is 0≦m≦4. ) (hereinafter sometimes simply referred to as a silicon compound); and an organoaluminum compound.

The dialkoxymagnesium used in the present invention includes jetoxymagnesium, dibutoxymagnesium, dialkoxymagnesium, dipropoxymagnesium, See-butoxymagnesium, di-t
Among them, ert-butoxymagnesium, diisopropoquine magnesium and the like are preferred, among which jetoxymagnesium and dipropoxymagnesium are preferred.

The diester of aromatic dicarboxylic acid used in the present invention is preferably a phthalic acid diester, such as dimethyl phthalate, diethyl phthalate, dipropyl phthalate, diisopropyl phthalate, dibutyl phthalate, diisobutyl tuclate, cyamyl 7-thaleate, diisoamyl phthalate, Examples include ethyl butyl phthalate, ethyl isobutyl phthalate, and ethyl propyl phthalate.

The aromatic hydrocarbon used in the present invention is preferably an aromatic hydrocarbon that is liquid at room temperature, such as toluene, 0-
Examples include xylene, m-xylene, p-xylene, benzene, ethylbenzene, propylbenzene, trimethylbenzene, and the like.

Examples of the titanium halide used in the present invention include T1014, TiBr, and Ti-6, among which Ti0Z is preferred.

The silicon compound used in the present invention is c)
Examples include phenylalkoxysilane and alkylalfukidisilane. Furthermore, examples of phenylalkoxysilane include phenyltrimethoxysilane, phenyltriethoxysilane, phenyltripropoxysilane, phenyltriisopropoxysilane, diphenyldimethoxysilane, diphenyljethoxysilane, etc. Examples of alkylalkoxysilane include , tetramethoxysilane, tetraethoxy7rane, trimethoxyethylsilane/, trimethoxymethylsilane, triethoxymethylsilane, ethyltriethoxysilane, ethyltriisopropoxysilane and the like.

When obtaining the catalyst component in the present invention, the proportion of each raw material used, contact conditions, etc. are arbitrary as long as they do not adversely affect the performance of the catalyst component to be produced, and are not particularly limited. Usually dialkoxymagnesium is 12, while aromatic dicarboxylic acid diester is 0.01 to 2.
It is preferably in the range of CL1 to 1F, and the titanium halide is in the range of CL1f or more, preferably 1f or more. Further, the aromatic hydrocarbon can be used in any proportion, but it is preferably in an amount that can form a suspension.

Furthermore, the contact between each raw material is usually carried out at a temperature between 0°C and the boiling point of the titanium halide used for up to 100 hours.
It is preferably carried out for 10 hours or less.

At this time, the order and method of contacting each raw material are not particularly limited, and any suitable method can be selected.

It is also possible to contact the product obtained after the above-mentioned contact with a titanium halide, and it is also possible to wash it using an organic solvent such as n-hebutane.

The heat treatment of the product obtained as described above is carried out after drying the product into a powder state, usually at a temperature of 30° C. or higher for 1 minute or more, preferably 5 minutes or more.

In addition, at this time, it is also possible to perform the heat treatment under increased pressure or reduced pressure.

The catalyst component produced as described above is combined with the silicon compound and organoaluminum compound to form a catalyst for polymerizing olefins.

The organoaluminum compound used has a molar ratio of 1 to 1000 per mole of titanium atoms in the catalyst component, and the silicon compound has a smol ratio of 1 or less per mole of the organoaluminum compound, preferably α005 to α5. Used within the range of

Polymerization can be carried out in the presence or absence of an organic solvent, and the olefin monomer can be used in either gas or liquid state. The polymerization temperature is 20
The temperature is 0°C or lower, preferably 100°C or lower, and the polymerization pressure is 1
ookii+/-・G or less, preferably 50 Y/-・G
It is as follows.

The olefins to be homopolymerized or copolymerized using the catalyst produced by the method of the present invention are ethylene, propylene,
1-buty/etc.

〔Effect of the invention〕

When olefins are polymerized using the catalyst component obtained according to the present invention, the catalyst has extremely high activity, so the amount of catalyst residue in the resulting polymer can be kept to an extremely low level, and the amount of residual chlorine is very small. Therefore, the influence of chlorine on the produced polymer can be reduced to such an extent that a deashing step is not required at all.

Chlorine contained in the produced polymer not only causes corrosion of equipment used in processes such as granulation and molding, but also causes deterioration and yellowing of the produced polymer itself, which could be reduced. This has extremely important meaning for those skilled in the art.

Furthermore, the present invention is characterized by not only solving the major problem of odor of the produced polymer by not using an aromatic carbo/acid ester during polymerization, but also allowing the activity per unit time of the catalyst to change over the course of polymerization. The purpose is to solve the essential drawbacks of so-called high-activity supported catalysts, which result in a significant decrease in activity, and to provide a catalyst that can be practically applied not only to homopolymerization but also to copolymerization.

Conventionally, in the industrial production of olefin polymers, it has been common to allow hydrogen to coexist during polymerization from the viewpoint of controlling the M process, but the catalyst using the catalyst component with magnesium chloride as a carrier In coexistence, the activity and stereoregularity were significantly reduced.

However, when olefins are polymerized in the coexistence of hydrogen using the catalyst obtained according to the present invention, the activity and stereoregularity hardly decrease even when the M engineering of the resulting polymer is extremely high. First, such an effect will bring extremely great benefits to those skilled in the art.

In addition, in industrial polymerization equipment, it is sometimes necessary to feed the catalyst into a high-temperature polymerization tank, and conventional supported catalysts have poor performance, especially activity and stereoregularity, in such cases. , bulk specific gravity, etc. are known to decrease. This is a big problem especially in the so-called continuous slurry polymerization method using an organic solvent, and there has been a strong demand for its improvement in this field, but the catalyst of the present invention satisfactorily solves this problem.

[Examples and comparative examples]

The present invention will be specifically explained below using Examples and Comparative Examples.

Example 1 <Preparation of catalyst and medium components>
101 of jetoxymagnesium and 80 of toluene were charged into a round bottom flask to form a suspension, and then Tie/ was added to this suspension.

Add 20- and raise the temperature to 90℃ to dibutyl phthalate) 2
-7- was added, and the temperature was further raised to 115°C for 2 hours with stirring. Toluene 100 at 90℃ after reaction completion
- twice with 80 eIt of toluene, Tic
! /, 20 tLt was added, and the mixture was reacted with stirring at 115°C for 2 hours. After the completion of the reaction, H-heptane 20 (
After washing with ItLt 10 times, the product was dried under reduced pressure. At this time, the titanium content of the product was 2.61.
% by weight. Next, the product was placed in a round bottom flask with an internal volume of 1001 rLt that was sufficiently purged with nitrogen gas, and
The mixture was heat-treated at 00°C for 1 hour to obtain a catalyst component.

Polymerization> 700 mZ of n-hebutane was charged into an autoclave with an internal volume of 2.0 t and equipped with a stirrer, which was completely purged with nitrogen gas, and triethylaluminum was added while maintaining the nitrogen gas atmosphere.
1011n9, phenyltriethoxysilane 64m9 were charged. Thereafter, the temperature was raised to 80°C and the catalyst component was heated to 1 [
Charge LO ■ and hydrogen gas 120-, and introduce propylene gas to 6' to 9/cr! -G pressure was maintained for 4 hours. After the polymerization was completed, the obtained solid polymer was separated, heated to 80° C., and dried under reduced pressure.

-The amount of polymer dissolved in the polymerization solvent by condensing the liquid F is taken as the amount of the polymer, and the amount of the solid polymer is taken as the amount of the solid polymer. Further, the obtained solid polymer was extracted with boiling n-hebutane for 6 hours to obtain a polymer insoluble in n-hebutane, and this amount was designated as [C1].

The polymerization activity per catalyst component was expressed by the formula and the yield (g) of the crystalline polymer was expressed by the formula, and the yield (g) of the total crystalline polymer was determined according to the formula 6 (%). In addition, the residual chlorine in the produced polymer is expressed as (Gl), the M concentration of the produced polymer is expressed as (5), and the bulk specific gravity is expressed as (Sword).

The results obtained are as shown in Table 1.

Example 2 An experiment was conducted in the same manner as in Example 1 except that the polymerization time was changed to 6 hours. The results obtained are shown in Table 1.

Example 3 Heat treatment at 100°C for 1 hour in Example 1 was changed to 80°C
The experiment was conducted in the same manner as in Example 1, except that the experiment was conducted for 3 hours. The results obtained are as shown in Table 1.

Comparative Example 1 The product obtained in Example 1 was used as it was as a catalyst component without being heat-treated. For polymerization, Experiment 2 was conducted in the same manner as in Example 1.

The results obtained are shown in Table 1.

Table 1

[Brief explanation of drawings]

FIG. 1 is a schematic drawing to aid in understanding the invention.

Claims (1)

[Claims] (1) (I) (a) Dialkoxymagnesium, (b
) A catalyst component obtained by heat-treating a product obtained by contacting a diester of an aromatic dicarboxylic acid, (c) an aromatic hydrocarbon, and (d) a titanium halide in a powder state; (II) A catalyst component obtained by the general formula SiRm ( OR')_4_-_m (in the formula R
is hydrogen, an alkyl group or an aryl group, R' is an alkyl group or an aryl group, and m is 0≦m≦4. ); and (III) an organoaluminum compound.