JPS6010523B2 - Method for purifying olefin polymer - Google Patents

Description

[Detailed description of the invention] The present invention relates to a method for purifying olefin polymers.

That is, halogen-containing magnesium solids, titanium compounds,
The present invention relates to a method for removing halogen components contained in an olefin polymer obtained using a catalyst consisting of an electron donor and an organometallic compound.

When obtaining an olefin polymer using a Ziegler-Natsuta type catalyst, it is possible to increase the amount of olefin polymer per transition metal by using a catalyst consisting of a magnesium compound, a halogen, a transition metal compound, an electron donor, and an organometallic compound. can. Therefore, the transition metal content in the olefin polymer is at a level that can be used as a product as it is. For example, in the case of ethylene polymer, it is used as a product without post-treatment after polymerization. However, in the case of polypropylene and the like, since it is necessary to maintain high stereoregularity, the catalytic activity is somewhat low, and the polymerization is carried out with a low amount of transition metal, etc. Therefore, the olefin polymer produced by the Ziegler-Natta type catalyst has a high halogen content, and when used directly as a product, rust may occur on the molding machine or mold. However, it is necessary to use a large amount of alcohol for the olefin polymer, and the cost of regenerating the alcohol is high. Tokukan Sho 49-187782 describes a method for dechlorinating olefin polymers by adding alkylene oxide in the granulation process, but in addition to requiring a special granulator, alkylene oxide Handling oxides is dangerous.

In addition, Samurai Kaisho 52-6 Group 88 reported that polyolefins containing catalyst residual light obtained by using a transition metal compound supported on magnesium halide as one catalyst component were used in aromatic monocarboxylic acids, polycarboxylic acids, or oxycarboxylic acids. A method of contacting with an acid is described.

However, acids interact with additives such as stabilizers, and the pellets produced tend to foam. Therefore, there is a need for an effective dehalogenation method that involves adding a small amount of a more neutral compound and using simple operations. The present inventors kept the above points in mind and as a result of intensive studies, the halogens present in the olefin polymer obtained using a catalyst consisting of a halogen-containing magnesium solid, a titanium compound, an electron donor, and an organometallic compound were found. It has been found that the chlorine content in an olefin polymer can be reduced by contacting the olefin polymer with a carboxylic acid anhydride.

That is, the first invention is a method for reducing halogen present in an olefin polymer obtained using a catalyst consisting of a halogen-containing magnesium solid, a titanium compound, an electron donor, and an organometallic compound. A second invention is a method for purifying an olefin polymer, which is characterized in that the olefin polymer is brought into contact with an anhydride, and the olefin polymer is brought into contact with a carboxylic acid anhydride and an aliphatic carboxylic acid having 8 to 30 carbon atoms or a metal salt thereof. 0.05-10 mol/carboxylic acid anhydride 1
A method for purifying an olefin polymer, the method comprising contacting the olefin polymer with a mixture containing a molar amount of the olefin polymer.

The catalyst of the present invention will be explained.

The halogen-containing magnesium solid referred to in the present invention is generally well known (in the following formula, R represents a hydrocarbon group) (1) obtained by reacting an organic Mg compound (Mg-R compound) with a CI compound. solid, i.e. [i]
Solid obtained by reacting Mg-R with a compound containing H-Si-CI (ii) Q-CI, C-CI, S
Solid m) obtained by reacting n-CI, containing compounds, etc.
Organic Mg compound (Mg-OR compound) Mg(OR)2
Solid (m) inorganic Mg obtained by reacting a CI compound with
Examples include C1, Mg(OH)CI, and the like.

Next, referring to Japanese Patent Application Laid-open Publications and Japanese Patent Publications, these compounds are further clarified.
ll): MgC12, Special Publication Showa 43-13050 (Sol
vay): Mg(OH)CI, Special Publication No. 47-1421
37 (Solvay): Mg (OR) 2, Mochikosho 47
-41676 (Montedison): M or 12,
Special Public Service No. 52-3 Group 31 (Montedison): M
gC12, Special Publication Showa 46-34092 (Mitsui Oil Science) M
gC12, Japanese Patent Publication No. 46-34098 (HMkst): Solid Japanese Patent Publication No. 46-34096 (Hockst) MgC121 made by reacting R)2 of Mg with a halogenating agent.
mMg(OH)2, Kimiaki Hakama 46-319 muscle (Snemicarbor) R-M
A solid obtained by reacting g with AI-CI JP-A-54-5893
(Asahi Kasei) Solid Special Seki Showa 5 made by reacting R-M g with H-Si-CI
3-70991 (Asahi Kasei) R-Solid hakama produced by reacting Mg with H-Si-CI Sekisho 53-146290 (Asahi Kasei) R
Examples include a solid obtained by reacting -Mg with a halogenating agent.

Generally well-known titanium compounds include tetravalent titanium having the general formula Ti(OR)nX4-n [wherein R: hydrocarbon having 1 to 10 carbon atoms; X: halogen C
I, B, 1; n is the number OSnS3] Or, examples of trivalent titanium include TIC13, TiBr3, and solid solutions and mixed crystals thereof.

Publications disclosing representative examples of these include Hakama Kosho 39-12105 (Shell) Tsubaki Kosho 46-31968 (Stami Karpon) Tokko Sho 52-39431 (Montegison) Tokuseki Sho 54-5
893 (Asahi Kasei) JP-A No. 53-70991 (Asahi Kasei) Tokukai Sho 53-146290 (Asahi Kasei).

Generally well-known electron donors include carboxylic acids, carboxylic acid halides, carboxylic anhydrides, carboxylic anhydride alcohols, and the like.

Publications disclosing representative examples include: Jikai Sho 54-5893 (Asahi Kasei) Hakama Sekiaki $-70991 (Asahi Kasei) Samurai Kai Sho 53-146290 (Asahi Kasei) Hakama Kimiaki 39-12105 (Shell) Hakama Kimiaki 46-31968 ( Stami Carpon) Special Publication 52-39431 (Montegison) Special Publication 1977-34
092 (Mitsui Petrochemical), etc.

Generally known as organometallic compounds,
Examples include organoaluminum compounds, organomagnesium compounds, and organozinc compounds.

Publications disclosing typical examples include
(Asahi Kasei) Tokukai Showa-70991 (Asahi Kasei) Hakama Kai Sho 53-146290 (Asahi Kasei) Tokuko Sho 46-319 clothes (Stami Carbon) Tokuko Tokko Sho 52
-39431 (Montegison) Hakama Kosho 46-416
76 Naka (Montegison) Special Public Service 1977-34092
(Mitsui Petrochemicals), etc.

The first feature of the present invention is that the olefin polymer foams less.

The second feature of the present invention is that the amount of carboxylic acid anhydride added to the olefin polymer is small.

This is particularly noticeable in the second invention. As the carboxylic anhydride (hereinafter referred to as a processing agent) used in the method of the present invention, aliphatic, alicyclic and aromatic monocarboxylic anhydrides and polycarboxylic anhydrides can be used.

For example, monocarboxylic anhydrides include oleic anhydride, palmitic anhydride, stearic anhydride, benzoic anhydride, tolylic anhydride, salicylic anhydride, and the like. Examples of polycarboxylic anhydrides include malonic anhydride, succinic anhydride, daltaric anhydride, adipic anhydride, azelic anhydride, sebacic anhydride, maleic anhydride, sebacic anhydride, and maleic acid. anhydride,
Examples include fumaric anhydride, citraconic anhydride, itaconic anhydride, cyclohexanedicarbosoic anhydride, nadic anhydride, phthalic anhydride, benzenetricarboxylic anhydride, and pyromellitic anhydride.

* In the method of the present invention, the olefin polymer can be brought into contact with the processing agent while the olefin polymer is in a molten state, or a kneader, a Banbury mixer, etc. can be used, and an extruder with a pent gives preferable results.

The processing agent is mixed with an olefin polymer in advance,
Alternatively, it can be added simultaneously or during the extruder. The amount of the treatment agent used is usually 0.005 to 5 parts by weight, preferably 0.01 to 2 parts by weight, per 100 parts by weight of the olefin polymer.

Below the above range, the effects of the present invention cannot be obtained. Although it may be used above the above range, it only increases the cost. The contact time between the olefin polymer and the treatment agent may be about 2 to 30 minutes when an extruder is used, and 1 to 40 minutes when a Banbury mixer or the like is used.
Hereinafter, the method of the present invention will be explained in detail with reference to Examples.

Examples 1 to 5 and Comparative Examples 1 to 3 In 10 hmol of trichlorosilane (heptane solution), organomagnesium Zentaiyama M&. oEze. 9n-Bu8
．． , 10 hmol was added dropwise at 65°C over 1 hour, and 1 mmol of ethyl benzoate was added to the obtained solid, and 1 mmol of ethyl benzoate was added to react, and 70 molar of titanium tetrachloride was added to the obtained solid. and treated at 130 qo for 2 hours.

Thereafter, the obtained solid was pulverized in a vibrating ball mill for 5 hours, and 100 I of titanium tetrachloride was further added to the obtained powder,
It was treated with 130qo. After adding the treatment agent shown in Table 1 to 10 parts by weight (chlorine content: 10%) of polypropylene powder produced using the solid catalyst (Ti content: 2.8% by weight) thus obtained, Using an extruder with a pent, the pressure at the vent part was reduced to 5 Yanagi Hg or less, and the pellet was extruded into a pellet. The residual amount of chlorine in this pellet is
Measured by line. The results are shown in Table 1. For comparison, ethanol, methyl isophthalate, and
Tests were conducted with and without terephthalic acid.

The results are shown in Table 1. Table 1 In addition, in Examples 1 to 5,
The collar of the obtained pellet and the mechanical properties of the molded product were good.

Examples 6 to 12 To the weight part of the polypropylene powder 10 used in Example 1,
The treatment agents shown in Table 2, aliphatic carboxylic acids and their metal salts were added, and the mixed bran was extruded into pellets using a vented extruder in the same manner as in Example 1. The residual amount of was measured by X-ray.

The results are shown in Table 2. Table 2

Claims (1)

[Scope of Claims] 1. A method for reducing halogen present in an olefin polymer obtained using a catalyst comprising a halogen-containing magnesium solid, a titanium compound, an electron donor, and an organometallic compound, wherein the olefin polymer 100 is A method for purifying an olefin polymer, which comprises contacting 0.005 to 5 parts by weight of a carboxylic acid anhydride. 2. An olefin polymer obtained using a catalyst consisting of a halogen-containing magnesium solid, a titanium compound, an electron donor, and an organometallic compound is added to a carboxylic acid anhydride with an aliphatic carboxylic acid having 8 to 30 carbon atoms or a metal salt thereof. 0.0
A method for purifying an olefin polymer, the method comprising contacting with a mixture containing 5 to 10 moles/carboxylic acid anhydride/mol. 3. The method for purifying an olefin polymer according to claim 1 or 2, wherein the carboxylic anhydride is a polycarboxylic anhydride.