JPH08134136A - Method for modifying polyolefin - Google Patents

Abstract

PURPOSE: To efficiently modify a polyolefin and obtain a resin improved in characteristics such as solvent resistance and adhesiveness to a polar group- containing polymer and gas permeability by subjecting a specific polyolefin to contact treatment with a catalyst and a hydrazine compound. CONSTITUTION: (A) A copolymer of an alkenylsilane (AI) such as a compound of the formula, CH2=CH-(CH2 )n -SiHp R3 [R is a 1-12C hydrocarbon group; (n) is 0-12; (p) is 1-3] with an olefin (AII) is subjected to contact treatment with (B) a catalyst such as a compound of the formula, R<1> n M(O-R<2> )4-n [R<1> and R<2> are each a 1-12C hydrocarbon group; M is Ti, Xr or Hf; (n) is 0-3] and (C) a hydrazine compound such as a compound of the formula, R-HN-NH-R [R is H or 1-12C hydrocarbon] to modify the component A. In respect to a polymerization ratio of AI to AII in the component A, AI is 0.001-30mol%, especially 0.005-10mol% and the component C is used in an amount of 0.01-1000 equivalent times based on AI.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for modifying a polyolefin. Specifically, it relates to a method for modifying a polyolefin, which comprises treating a polyolefin copolymerized with a specific monomer with a catalyst and a hydrazine compound.

[0002]

2. Description of the Related Art It is widely practiced to graft-polymerize and modify a polyolefin for the purpose of improving solvent resistance, improving adhesion with a polymer containing a polar group, and improving gas permeability. . It is easy to mix a polar group-containing monomer and a radical generator with a polyolefin, and heat-melt and graft-polymerize it, but the purpose is to cause side reactions such as decomposition of the polyolefin or homopolymerization of the monomer. It is difficult to cause only the graft polymerization of On the other hand, it is considered that the group which reacts easily with the polyolefin is introduced by polymerization to react, but it is possible to introduce a starting point without deteriorating the physical properties of the polyolefin, and to make it effective. It is extremely difficult to introduce a polar group by utilizing it, and an effective method has not been known.

[0003]

On the other hand, it is desired to develop a method capable of effectively modifying polyolefin.

[0004]

[Means for Solving the Problems] The present inventors have completed the present invention by intensively studying a method for solving the above problems and simply modifying and modifying a polyolefin.

That is, the present invention is a method for modifying a polyolefin, which comprises subjecting a copolymer of an alkenylsilane and an olefin to a contact treatment with a catalyst and a hydrazine compound.

In the present invention, an alkenylsilane having at least one Si--H bond is preferably used, and for example, a compound represented by the following general formula (Formula 1),

[0007]

Embedded image H ₂ C═CH— (CH ₂ ) _n —SiH _p R _3-p (wherein n is 0 to 12, p is 1 to 3 and R is a hydrocarbon residue having 1 to 12 carbon atoms). ) Can be exemplified, and specifically, vinyl silane,
Examples thereof include allylsilane, butenylsilane, pentenylsilane, and compounds in which H of some Si—H bonds of these monomers is replaced with chlorine.

As the olefin, a compound represented by the following general formula (Formula 2),

[0009]

Embedded image H ₂ C═CH—R (wherein R is hydrogen or a hydrocarbon residue having 1 to 12 carbon atoms.)
Can be exemplified, and specifically, ethylene, propylene, butene
In addition to α-olefins such as -1, pentene-1, hexene-1, 2-methylpentene, heptene-1, and octene-1, styrene and its derivatives are also exemplified.

In the present invention, the copolymer of alkenylsilane and olefin can be produced by a bulk polymerization method or a gas phase polymerization method in addition to the solvent method using an inert solvent. As the catalyst used for production, a catalyst composed of a transition metal compound and an organometallic compound is generally used, and a titanium halide is preferably used as the transition metal compound and an organoaluminum compound is preferably used as the organometallic compound.

Specifically, titanium tetrachloride obtained by reducing titanium tetrachloride with metallic aluminum, hydrogen or organic aluminum is modified with an electron-donating compound, an organoaluminum compound, and if necessary, an oxygen-containing organic compound. Such as a catalyst system composed of an electron donating compound, a carrier such as magnesium halide, or a transition metal compound catalyst obtained by supporting titanium halide on the carrier treated with an electron donating compound and an organoaluminum compound, if necessary. A catalyst system consisting of an electron-donating compound such as an oxygen-containing organic compound or a reaction product of magnesium chloride and an alcohol is dissolved in a hydrocarbon solvent and then treated with a precipitating agent such as titanium tetrachloride to form a hydrocarbon solvent. Insolubilize, treat with electron donating compounds such as ester and ether if necessary, then Examples include catalyst systems comprising a transition metal compound catalyst and an organoaluminum compound obtained by a method of treatment with titanium rogenide, and optionally an electron-donating compound such as an oxygen-containing organic compound (see, for example, various references below. An example is given of: Ziegler-Natta Ca
talysts and Polymerization by John Boor Jr (Academi
c Press), Journal of Macromolecular Science Reviews
in Macromolecular Chemistry and Physics, C24 (3) 355
-385 (1984), C25 (1) 578-597 (1985)).

Alternatively, the polymerization can be carried out by using a transition metal catalyst soluble in a hydrocarbon solvent and a catalyst composed of aluminoxane.

As the electron-donating compound, oxygen-containing compounds such as ethers, esters, orthoesters and alkoxysilicon compounds can be preferably exemplified, and alcohols, aldehydes, water and the like can also be used.

As the organoaluminum compound, trialkylaluminum, dialkylaluminum halide, alkylaluminum sesquihalide and alkylaluminum dihalide can be used, and examples of the alkyl group include methyl group, ethyl group, propyl group, butyl group and hexyl group. Examples of the halide include chlorine, bromine and iodine. Further, an aluminoxane which is an oligomer or a polymer obtained by reacting the above organoaluminum with water or water of crystallization can also be used.

The alkenylsilane / olefin polymerization ratio is usually about 0.001 to 30 mol%, preferably 0.005 to 10 mol%. When mixed with other olefin polymers, it is
It is 20 mol%.

The molecular weight of the polymer is not particularly limited, and the molecular weight is determined according to the purpose. In terms of physical properties, it is better that the molecular weight is relatively high, but in terms of moldability, if the molecular weight is too high, moldability deteriorates.
Intrinsic viscosity of 0.2 to 10 measured with tetralin solution at 135 ℃
It is generally about 0.5 to 5.0, particularly preferably about 0.5 to 5.0.

A graft copolymer obtained by graft-polymerizing an alkenylsilane on a polyolefin (for example, the following mixed polyolefin can be used) can be used for the purpose of the present invention. There is no particular limitation as to the method for grafting alkenylsilane to the above, and the methods and conditions used in ordinary graft copolymerization can be used. Normally, the polyolefin and alkenylsilane used are radical initiators in the presence of a radical initiator such as peroxide. Graft copolymerization can be easily carried out by heating above the decomposition temperature of.

In the present invention, the above copolymer and polyolefin may be mixed and used, if necessary, and the polyolefin to be used is an olefin represented by the general formula (formula 2), specifically ethylene, propylene and butene.
-1, pentene-1, hexene-1, 2-methylpentene, heptene-1, octene-1 and other α-olefins, or homopolymers of styrene or its derivatives, random copolymers of each other, or Examples thereof include so-called block copolymers produced by copolymerizing olefins alone or with a small amount of other olefins, and then copolymerizing two or more kinds of olefins.

Methods for producing these polyolefins are already known and various brands are available on the market. It can also be produced by the same method as the above-mentioned method for producing a copolymer of alkenylsilane and olefin except that alkenylsilane is not used.

In the present invention, examples of the hydrazine compound include compounds represented by the following general formula (Formula 3). The amount of the hydrazine compound used is generally 0.01 to 1000 equivalent times the alkenylsilane in the copolymer of olefin and alkenylsilane, and if less than 0.01 equivalent, almost no reaction occurs. No, 100
Even if it is used in excess of 0 equivalent, it is not particularly effective and economical.

[0021]

Embedded image (In the formula, R is hydrogen or a hydrocarbon residue having 1 to 12 carbon atoms).

In the present invention, a rhodium salt such as a cyclooctadiene complex of rhodium chloride or a triphenylphosphine complex can be preferably used as the catalyst, and a salt of platinum, chloroplatinic acid, a benzonitrile complex of platinum chloride, or Preferable examples of the use of an alkoxy compound of Group IVB metal of the periodic table represented by the following general formula (Formula 4) such as a titanate alone or in combination with an organometallic compound are preferred.

[0023]

Embedded image R ¹ _n M (OR ² ) _4-n (wherein R ¹ and R ² are the same or different hydrocarbon residues having 1 to 12 carbon atoms, n is an integer of 0 to 3 and M is titanium). , A metal selected from zirconium and hafnium.).

In the present invention, the method of contact-treating the alkenylsilane / olefin copolymer with a catalyst and a hydrazine compound may be carried out by dissolving the alkenylsilane / olefin copolymer powder, pellets or molded product in the catalyst and the hydrazine compound. Method of contacting by dispersing in a solution, a method of contacting a hydrazine compound with a mixture of an alkenylsilane / olefin copolymer and a catalyst in advance, and further heating and melting and mixing of an alkenylsilane / olefin copolymer and a catalyst in advance. Examples of the method include contacting a molded product with a hydrazine compound. The amount of catalyst used here is 0.0 in terms of concentration in the solution or molded product.
It is generally 1 to 1000 ppm.

There is no particular limitation on the method of molding the molded product used in the treatment with the solution of the catalyst and the hydrazine compound, as long as a copolymer of alkenylsilane and olefin is used, the molding can be carried out by a conventional molding method. The copolymer alone, or other polyolefin of the copolymer, further filler, etc., is melted and mixed with a phenolic stabilizer by an extrusion molding method,
It can be obtained by molding by an injection molding method, a press molding method, a blow molding method, or the like. As the filler, metal hydroxides, oxides, nitrides, carbides and the like having needle-like shape, scale-like shape, fibrous shape and the like having a large reinforcing effect are preferably used. Specifically, talc,
Kaolin, mica, calcium carbonate, calcium silicate,
Calcium sulfate, calcium sulfite, barium titanate, etc. can be used.

There are no particular restrictions on the method of heating, melting and mixing the alkenylsilane / olefin copolymer and the catalyst, and examples thereof include injection molding, extrusion molding, press molding, blow molding, and the like. After mixing the olefin copolymer and the catalyst well at low temperature and then heat-melting and molding by press molding, or the catalyst is heat-melted and mixed with the alkenylsilane-free polyolefin to form a master pellet of the catalyst. It is also possible to mix pellets obtained by heating and melting an alkenylsilane / olefin copolymer, polyolefin, or an additive other than a catalyst, such as an antioxidant, and injection molding. At the time of molding, it is possible to mix various fillers, and those same as those described above can be used.

The alkenylsilane concentration in the molded product is generally 0.001 to 20 mol%, preferably 0.01 to 10 mol%.

The molding temperature is a temperature at which the polymer can be melt-molded, and is about 150 to 300 ° C.

The contact temperature for contacting the hydrazine compound or the mixture of the hydrazine compound and the catalyst is from room temperature to 150 ° C. It is effective to contact the molded product at a temperature as high as possible unless the molded product is deformed. The same applies to the case of contact in the powder state, but in this case, even if the powder is deformed, there is no problem depending on the case, and the preferable range of the contact temperature is widened. The contact time is several minutes to several hours. The hydrazine compound is used in solution,
As the solvent used here, a hydrocarbon compound having 1 to 20 carbon atoms is generally used, but a hydrazine compound can also be used as the solvent. Specifically, aliphatic hydrocarbons such as hexane, heptane, octane, etc., aromatic hydrocarbon compounds such as benzene, toluene, xylene, ethylbenzene, cumene, etc. can be used, and the concentration of the hydrazine compound is usually 100 to 1%. It is generally dissolved in and used.

[0030]

EXAMPLES The present invention will be further described with reference to the following examples.

Example 1 A vibration mill equipped with four grinding pots having an inner volume of 4 liters and containing 9 kg of steel balls having a diameter of 12 mm was prepared. In each pot under a nitrogen atmosphere, 300 g of magnesium chloride, 60 ml of tetraethoxysilane and 45 of α, α, α-trichlorotoluene
ml was added and crushed for 40 hours. Co-ground product 300 thus obtained
In a 5 liter flask, add 1.5 liters of titanium tetrachloride and 1.5 liters of toluene, and add 30 liters at 100 ° C.
After stirring for a minute, the supernatant was removed. Add again 1.5 liters of titanium tetrachloride and 1.5 liters of toluene,
The mixture was stirred at 100 ° C for 30 minutes, and the supernatant was removed. Then, the solid content was repeatedly washed with n-hexane to obtain a transition metal catalyst slurry. When a part of the sample was sampled and the titanium content was analyzed, the titanium content was 1.9 wt%.

40 ml of toluene, 100 mg of the above transition metal catalyst, 0.128 ml of diethylaluminum chloride, 0.06 ml of methyl p-toluate and 0.20 ml of triethylaluminum were placed in an autoclave having an internal volume of 5 liters under a nitrogen atmosphere, and 1.5 kg of propylene and 80 g of vinylsilane were added. In addition, hydrogen
After 0.5 N liter was injected under pressure, polymerization was carried out at 75 ° C for 2 hours. After the polymerization, unreacted propylene was purged, the powder was taken out, filtered and dried to obtain 480 g of powder.

The intrinsic viscosity (hereinafter abbreviated as η) was measured with a tetralin solution at 135 ° C., and the intrinsic viscosity was measured at 10 ° C./min using a differential thermal analyzer.
When the melting point and crystallization temperature were measured as the maximum peak temperature by raising or lowering at min, the obtained powder had η of 2.35, melting point 156 ℃, crystallization temperature 120 ℃
Was a crystalline propylene copolymer. According to elemental analysis, it contained 1.3 wt% of vinylsilane unit.

10 g of the obtained copolymer was dispersed in a solution of 100 mg of dimethyltitanocene and 20 g of methylhydrazine dissolved in 50 ml of toluene, and contact treatment was carried out at 30 ° C. for 2 hours. After the reaction, the copolymer powder was filtered, washed repeatedly with toluene, and then dried. After heating the obtained powder at 260 ℃, pressurizing it into a sheet with a thickness of 0.1 mm and measuring the infrared absorption spectrum, the absorption attributed to the Si-H bond at about 2160 cm ^-1 disappeared, and about 3150 cm. The absorption of NH bond was observed at ^-1 , confirming that it was modified with hydrazine. The increase in weight was 0.15%.

Example 2 Polymerization was carried out in the same manner as in Example 1 except that 18 g of allylsilane was used instead of vinylsilane to produce a propylene copolymer having an allylsilane content of 0.25 wt%. The η of the copolymer was 1.85, the melting point was 158 ° C., the crystallization temperature was 115 ° C., and the extraction residue ratio after extraction with boiling n-heptane for 6 hours was 96.8%.
The infrared absorption spectrum of the sheet was measured in the same manner as in Example 1 except that 10 g of this powder was used.
The absorption attributed to the Si-H bond at cm ^-1 disappeared, and about 3150 cm ^-1
Absorption of NH bond was observed in the sol, confirming that it was modified with hydrazine.

Example 3 Example except that hydrazine was used as the hydrazine compound.
1 and was measured infrared absorption spectrum into a sheet in the same manner, the absorption disappeared attributed to Si-H bonds of about 2160 cm ^-1, are observed absorption of NH bond at about 3150 cm ^-1,
It was confirmed that it was modified with hydrazine. The increase in weight was 0.18%.

[0037]

EFFECT OF THE INVENTION By carrying out the method of the present invention, the polyolefin can be modified efficiently and is industrially very valuable.

Claims (1)

[Claims] 1. A method for modifying a polyolefin, which comprises contacting a copolymer of an alkenylsilane and an olefin with a catalyst and a hydrazine compound.