JPH03157409A - Solid catalyst component for producing polyethylene - Google Patents

Abstract

PURPOSE:To obtain the title component providing polyethylene in high yield, extremely reducing influence of chlorine to the polymer because of its high activity by bringing diethoxymagnesium into contact with specific components such as TiCl4 in a specific order. CONSTITUTION:First, (A) diethoxymagnesium is brought into contact with (B) toluene to give a suspension comprising the components A and B, into which (C) an aromatic dicarboxylic acid diester (preferably phthalic diester such as dimethyl phthalate), (D) methylhydrogen polysiloxane and (E) titanium tetrachloride are brought into contact. Then the prepared composition is brought into contact with the component E in the presence of the component B to give the objective component having >=15wt.% titanium content in the composition. Usually >=5ml component B, 0.1-2g component C, 0.1-2ml component D and >=5ml component E are preferably used based on 1g component A.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention provides a high-performance solid medium component that can obtain polyethylene in high yield when subjected to ethylene polymerization.

[Conventional technique Wr] Conventionally, polyethylene was used for vibrators, fuel tanks, and capacity ltg.
, food packaging film,! industrial films and sheets,
It is widely used in shopping bags, garbage bags, daily necessities, miscellaneous goods, etc. In order to produce such polyethylene, a so-called Ziegler catalyst, which is a combination of a solid catalyst component containing a transition metal component and an organoaluminum compound, has been used. It is generally known that titanium trichloride catalyst components and magnesium-supported titanium-based solid catalyst components are conventionally used as solid catalyst components containing the above-mentioned transition metal components.

[Problem M to be solved by the invention] Three conventionally known titanium catalyst components (h) are used in the production of polyethylene in combination with diethylaluminum chloride, Since the yield of the polymer (hereinafter referred to as catalytic activity) is low, there is a large amount of catalyst residue in the produced ethylene polymer.Therefore, a so-called deashing process is carried out to remove the residual catalyst contained in the obtained polymer and decolorize it. was inevitable.

This deashing process uses a large amount of alcohol or chelating agent, so it is essential to recover them, and a
There were many problems related to S, energy, and other problems, and it was an important problem that those skilled in the art needed to solve immediately. For this reason, in recent years, many proposals have been made in which a magnesium-supported titanium-based solid catalyst component is used in combination with an alkyl aluminum. However, although these known catalysts are superior in that the catalytic activity per unit transition metal is improved, the catalytic activity per positioning catalyst including the support is still insufficient in many cases. In terms of activity, it is preferable not only to have a high polymer yield per unit transition metal, but also to have a high polymer yield per radical catalyst in terms of process operation and manufacturing cost. 63-496
As disclosed in Japanese Patent Application No. 86 and the like, the mainstream requirements are to use magnesium chloride as the magnesium-supported titanium-based solid catalyst component and to use a titanium halide as the active component. The chlorine contained in this magnesium chloride has the disadvantage of having a negative effect on the produced copolymer, similar to the chlorine in titanium halides, and for this reason, the chlorine content is so high that the effect of chlorine can be virtually ignored. There remained 18 unresolved issues, such as the need for activity or the need to keep the concentration of magnesium chloride itself low.

[Means for Solving the Problems] The present inventors have conducted intensive research to develop a solid catalyst component for polyethylene production that can solve the problems left in the prior art, and as a result, they have arrived at this invention. This is what I propose here.

That is, the feature of the present invention is that (a) jetoxymagnesium is brought into contact with (b) toluene, and then (c) aromatic dicarboxylic acid diester, (d) methylhydrodiene polysiloxane, and (e) The titanium content in the composition obtained by contacting with titanium tetrachloride and further contacting the obtained composition with (e) titanium tetrachloride in the presence of (b) toluene is
It is an object of the present invention to provide a solid catalyst component for producing polyethylene, characterized in that the content thereof is 5% by weight or more.

The aromatic dicarboxylic acid diester (c) used in the present invention (hereinafter sometimes simply referred to as (c) substance) is preferably a phthalic acid diester, such as dimethyl phthalate, diethyl phthalate, dipropylphthalate, dibutyl phthalate, diisobutyl phthalate,
Examples include cyamyl phthalate, diisoamyl phthalate, ethyl butyl phthalate, ethyl isobutyl phthalate, and ethyl pro- and luphthalate.

(d) Methylhydrodiene polysiloxane (hereinafter simply referred to as (d) substance) used in the present invention is a polymeric silicon compound represented by the general formula, where n is lO≦n≦50, The viscosity is about 10 to 100 centistics at room temperature.

The solid catalyst component obtained in the present invention constitutes a polyethylene production catalyst when used in combination with an organoaluminum compound. The organoaluminum compound used in this case is represented by the general formula RnAlX3-n (where R is a hydrocarbon group, X is a halogen atom, and 1≦n≦3). Specifically, triethylaluminum, triisobutylaluminum, diethylaluminium chloride,
Examples include ethylaluminum sesquichloride, but it is also possible to use a mixture of these.

When obtaining the solid component in the present invention, raw materials (a) jetoxymagnesium (hereinafter sometimes simply referred to as (a) substance), (b) toluene (hereinafter sometimes simply referred to as (b) substance), (c ) substance, (d) substance, and (e) titanium tetrachloride (hereinafter sometimes referred to as (e)-trade).
b) After contacting the substances to form the suspension 111#fI, it is necessary to contact the substances (c), (d) and (e) under stirring. However, the contact between the (lk) substance and the suspension consisting of the (b) substance and the (c) substance, (d) substance, and (e) substance may be carried out in any order as long as the effects of the present invention are recognized. does not prevent you from doing
(e) The contact temperature with the substance is preferably 30°C or more and 130°C or less, and the contact time is in the range of 5 minutes or more, preferably 30 minutes or more and 100 hours or less. At this time, if the contact temperature is less than 30°C, the reaction will not proceed sufficiently, and if it is higher than 130°C, evaporation of the solvent, decomposition of the materials used, etc. will become noticeable, making it difficult to control the reaction.

Each substance can be used in any proportion as long as the titanium content in the final composition is 15% by weight or more, but usually (a) 1 g of the substance, (b) 5 ml or more of the substance , (c) The substance is 0. 1-2 g, (d) substance is 0. 1-2 ml; (e) the substance is in the range of 5 ml or more; In addition, in this case, a hydrocarbon solvent such as hexane, heptane, decane, benzene, xylene, etc. may be used as a diluent. Contact temperature is 30℃ or higher13
The temperature is preferably 0°C or lower, the contact time is 5 minutes or more,
Preferably it is in the range of 30 minutes or more and 100 hours or less. At this time, if the contact temperature is lower than 30°C, the reaction will not proceed sufficiently, and if it is higher than 130°C, evaporation of the solvent and decomposition of the materials used will become significant, making it difficult to control the reaction.

Note that the substance (e) and the substance (b) can be used in any proportion. Further, the obtained composition was further added to n-
It is also possible to wash using an organic solvent such as hebutane.

The solid catalyst component produced as described above is combined with the organoaluminum compound to form a catalyst for producing polyethylene. The aluminum compound used has a molar ratio of 1 to 100 per mole of titanium atoms in the solid catalyst component.
0 l! Polymerization is usually carried out in a hydrocarbon or halogenated hydrocarbon solvent, and the polymerization temperature is between 0 and 0.
150℃, polymerization pressure 0-100 kg/cts2・
It is G. At this time, a water bladder can be used as an auxiliary molecular weight regulator, and if necessary, electron-donating compounds such as esters, ketones, amines, and silicon compounds having Si-〇-C bonds can be used. It is also possible to use it by adding it.

[Functions and effects of the invention]

When polyethylene is produced using the solid catalyst component obtained by this invention, the catalytic activity is extremely high, so the influence of chlorine on the produced polymer can be reduced to the extent that no deashing step is required at all. . In addition, because of its excellent sustainability of activity during polymerization, it has the advantage of being less susceptible to deterioration during polymerization reactions that require a long time. Even if the amount of titanium is relatively small, it shows high catalytic activity, so when industrially producing the solid catalyst component, manufacturing costs can be reduced, and environmental measures related to waste liquid treatment etc. can be reduced. can do. Furthermore, when the solvent component is removed from the solid catalyst component to form a powder, there is almost no aggregation of particles, so additional effects such as cost reduction in process operations and equipment can be achieved. It is something.

[Example〕 The present invention will be specifically explained below using examples.

Example 1 *a>i! of the solid catalyst component In a round bottom flask with a capacity of 500 ml and equipped with a stirrer and fully exchanged with nitrogen gas, 5 ml of jetoxymagnesium was added.
g and 80mltM of toluene to form a suspension,
Furthermore, 10 ml of methylhydrogenpolysiloxane having a viscosity of 30 centistokes at room temperature was added and brought into contact at 60° C. for 1 hour to obtain Hanging 111 #11.

Next, 20 ml of titanium tetrachloride was charged to this suspension, and 7
Di-n-butyl phthalate 1°5 when heated to 0°C
ml was added thereto, and the temperature was further raised to react at 90°C for 2 hours. After that, it was washed three times with 100ml of toluene at 90°C.
After removing the supernatant liquid, 80 ml of toluene and 20 ml of titanium tetrachloride were added, and the mixture was reacted again at 110° C. for 2 hours. Finally, a solid catalyst component was obtained by washing 10 times with 200 ml of n-hebutane at 40°C. The titanium content in this solid catalyst component was 16.7% by weight.

Polymerization> Completely with ethylene gas! Inner volume: 1500m1
Stirring H! Charge 700 ml of n-hebutane into a stainless steel autoclave, and while keeping it in an ethylene gas atmosphere at 20°C, add triethylaluminum! ,OOm
mol was charged. Next, 0.02 mmol of the solid catalyst component as titanium atoms was charged, and the pressure in the system was raised to I.
Pressurize with ethylene to give 2 kg/cm'・G.
Prepolymerization was carried out at 0°C for 30 minutes. After that, a water bladder was introduced so that the pressure inside the system became 4 J/c■2・G, and while further ethylene was supplied, the total pressure was increased to 6 kg/cm2・c:
Then, the temperature was raised to 70° C. and polymerization was performed for 2 hours. 9 The pressure that decreased as the polymerization progressed was compensated for by continuously supplying only ethylene, and the pressure was kept constant during the polymerization.

Ethylene was polymerized according to the above polymerization method, and the resulting polyethylene powder was filtered and dried under reduced pressure.
．． 8 g, and the polymer yield per 1 g of catalyst at a polymerization time of 2 hours was 14,400 g/g-cat.
The bulk specific gravity of the obtained polymer was 0.24g/
ci+', and the average particle size expressed as 50% cumulative weight was 380 microns.

Example 2 Example! Using the solid catalyst component obtained in step 1, ethylene was polymerized as follows.

Polymerization> 700 ml of n-hebutane was charged into a stainless steel autoclave with an internal volume of 1,500 ml and equipped with a stirring B11 that had been completely replaced with ethylene gas, and 6.70 ml of triethylaluminum was added while maintaining an ethylene gas atmosphere at 20°C.
mol was charged. Next, 0.0052 mmol of the solid catalyst component was inserted as a titanium atom, and the system was pressurized with ethylene to a pressure of 1 kg/cm2·G, and prepolymerization was carried out at 20° C. for 30 minutes. After that, while supplying ethylene, the total pressure was set to 4J/c112・G, and the temperature was 70°C.
Polymerization was carried out for 3 hours. The pressure that decreased as the polymerization proceeded was compensated for by continuously supplying only ethylene, and the pressure was kept constant during the polymerization.

Ethylene was polymerized according to the above polymerization method, and the resulting polyethylene powder was filtered and dried under reduced pressure.
．． 7 g″r!, the polymer yield per 1 g of catalyst at 3 hours of polymerization time was 46,000 g/g-cat,
The bulk specific gravity of the obtained polymer is 0.28
g/cm', and the average particle size expressed as 60% of the cumulative weight was 380 microns.

Example 3 A solid catalyst component was prepared in the same manner as in Example 1, except that the contact conditions when adding methylhydrodiene polysiloxane were changed to 1 hour at 0°C. I5! The titanium content in the body catalyst component was 16.3% by weight.

The polymerization was conducted in the same manner as in Example 1. The polyethylene powder obtained by the polymerization was filtered and dried under reduced pressure, and the weight was 83.8 g.
Polymer yield per g is 14,300x/g-cat,
The bulk specific gravity of the obtained polymer was 0.25g.
/c■3, and the average particle size expressed as 50% of the cumulative weight was 450 microns.

It is a flowchart regarding a process.

Claims (1)

[Claims] (1) After contacting (a) diethoxymagnesium with (b) toluene, (c) aromatic dicarboxylic acid diester, (d) methylhydrodiene polysiloxane and (
e) contact with titanium tetrachloride, and further contact the resulting composition with (e) titanium tetrachloride in the presence of (b) toluene, such that the titanium content in the composition obtained is 15
A solid catalyst component for producing polyethylene, characterized in that the content is at least % by weight.