JP3171708B2 - Method for modifying polyolefin molded article - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for modifying a polyolefin molded product. More specifically, the present invention relates to a method for modifying a polyolefin molded product, comprising treating a polyolefin obtained by copolymerizing a specific monomer with an alkylene oxide.

[0002]

2. Description of the Related Art It is widely practiced to graft-polymerize polyolefins for the purpose of improving solvent resistance, improving adhesion to a polymer containing a polar group, and improving gas permeability. . It is easy to mix a monomer containing a polar group and a radical generator with a polyolefin and heat-melt it for graft polymerization, 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, and no compound other than the unsaturated compound can be introduced. On the other hand, it is conceivable to introduce a group which becomes a polymerization starting point into the polyolefin by polymerization and carry out graft polymerization.However, introducing a starting point without lowering the original physical properties of the polyolefin, and furthermore, It is extremely difficult to carry out the graft polymerization by utilizing it effectively, and no effective method has been known.

[0003]

It is desirable to develop an effective graft polymerization method capable of effectively modifying a polyolefin.

[0004]

Means for Solving the Problems The present inventors have solved the above-mentioned problems and have intensively studied a method for easily graft-polymerizing a polyolefin, and completed the present invention.

That is, the present invention provides a alkenylsilane / olefin copolymer and rhodium salt, platinum salt and
Formula (Formula 6)

Embedded image (Wherein R ¹ and R ² are the same or different and have 1 to 12 carbon atoms)
A hydride residue, n is an integer of 0 to 3, M is titanium, zirconium
Metal selected from uranium and hafnium. ) Period
This is a method for modifying a polyolefin molded product, comprising subjecting a molded product obtained by heat-melting a catalyst selected from an alkoxy compound of a Group IVB metal to contact with a gaseous alkylene oxide.

In the present invention, alkenyl silanes having at least one Si—H bond are preferably used, for example, a compound represented by the following general formula (Chemical Formula 1):

[0007]

Embedded image H ₂ C = CH— (CH ₂ ) _n —SiH _P R _3-P (where 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, specifically, vinyl silane,
Examples thereof include allylsilane, butenylsilane, pentenylsilane, and compounds in which H of Si—H bond in some of these monomers is substituted with chloro.

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

[0009]

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

In the present invention, the copolymer of olefin and alkenylsilane can be produced by a bulk polymerization method or a gas phase polymerization method in addition to a solvent method using an inert solvent. Further, a catalyst comprising a transition metal compound and an organometallic compound is generally used as a catalyst used in the production. 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 organic aluminum compound, and if necessary, an oxygen-containing organic compound. A catalyst system comprising an electron donating compound such as, or a carrier such as magnesium halide or a transition metal compound catalyst obtained by supporting them with an electron donating compound and supporting a titanium halide, and an organoaluminum compound. 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 precipitant such as titanium tetrachloride to form a hydrocarbon solvent. Insolubilize and treat with an electron-donating compound such as an ester or ether if necessary. Examples of the catalyst system include a transition metal compound catalyst obtained by a method of treating with a titanium logenide and an organoaluminum compound, and an electron-donating compound such as an oxygen-containing organic compound as required (for example, various types of compounds described in the following literature). Examples are described: Ziegler-Natta Ca
talysts and Polymerization by John Boor Jr (Academi
c Press), Journal of Macromorecular Science Reviews
in MacromolecularChemistry and Physics, C24 (3) 355
-385 (1984) and C25 (1) 578-597 (1985)).

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

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

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

Here, the polymerization ratio of the alkenylsilane to the olefin is usually about 0.01 to 30 mol%, preferably 0.1 to 10 mol%. When it is used in a mixture with another olefin polymer, the content is 1 to 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 to have a relatively high molecular weight, but in terms of moldability, if the molecular weight is too high, moldability deteriorates.
Intrinsic viscosity measured in tetralin solution at 135 ° C is 0.5 to 10
It is generally about dl / g , particularly preferably about 1.0 to 5.0 dl / g .

A graft copolymer obtained by graft-polymerizing an alkenylsilane onto a polyolefin (for example, a polyolefin used as a mixture as described below) can also be used for the purpose of the present invention. There is no particular limitation on the method of grafting the alkenyl silane to the method, and the method and conditions used for ordinary graft copolymerization can be used, and the usually used polyolefin and alkenyl silane are radical initiators in the presence of a radical initiator such as peroxide. The graft copolymerization can be easily performed by heating to a temperature equal to or higher than the decomposition temperature.

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

The methods for producing these polyolefins are already known, and various brands are available on the market. Alternatively, the alkenyl silane can be produced by using the same method as that for producing the copolymer of olefin and alkenyl silane except that alkenyl silane is not used.

The catalyst used in the present invention includes:
Rhodium salts such as rhodium chloride cyclooctadiene complex and triphenyl phosphine complex, platinum iodide, bromoplatinic acid, platinum chloride benzonitrile complex, and titanate ester are represented by the following general formula (Formula 3). alkoxy compound of periodic table group IVB metals indicated are found using.

[0021]

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 , Zirconium, hafnium.)

In the present invention, examples of the alkylene oxide include compounds represented by the following general formula (4) having a three-membered ring ether group in which oxygen is added to a carbon-carbon unsaturated bond.

[0023]

Embedded image (In the formula, R ₁ is hydrogen or a hydrocarbon residue having 1 to 20 carbon atoms.) Specific examples include ethylene oxide, propylene oxide, pentene oxide, hexene oxide, octene oxide, cyclohexene oxide, and styrene oxide.

In the present invention, the method of hot-melt molding the alkenylsilane-olefin copolymer and the catalyst is not particularly limited, but after the alkenylsilane-olefin copolymer and the catalyst are mixed well at a low temperature, Heat-melted and molded by press molding, or heat-melted and mixed a catalyst with an alkenylsilane-free polyolefin to form a catalyst master pellet, and a copolymer of alkenylsilane and olefin and additives other than the catalyst Can be injection-molded by mixing pellets obtained by heat-melting and mixing.

In the molding, various fillers can be mixed, such as metal hydroxides, oxides, nitrides, carbides, and the like, needle-like, scale-like, fibrous, etc. Those having a shape having a large reinforcing effect such as those having a reinforcing effect are preferably used. Specifically, talc, kaolin, mica, calcium carbonate, calcium silicate, calcium sulfate, calcium sulfite, barium titanate and the like can be used. Examples of the molding method include injection molding, extrusion molding, and press molding. The molding temperature is a temperature higher than the melting point of the polyolefin, usually 150 to 300 ° C.

Here, the amount of the catalyst is 0.1 to 10000 ppm, preferably 1 to 5000 ppm as the concentration of the catalyst in the molded article.
Mix so that When the alkenyl silane in the molded product is mixed so as to have a concentration of 0.01 to 20 mol%, preferably 0.1 to 10 mol%, it is possible to graft alkylene oxide at a high concentration.

In the present invention, the molded product comprising the alkenylsilane / olefin copolymer and the catalyst is contacted with an alkylene oxide. At this time, the alkylene oxide is brought into contact in a gaseous state, whereby it is possible to avoid deformation of the molded product during graft polymerization. It is effective that the contact temperature is from room temperature to 150 ° C., particularly above the boiling point of alkylene oxide. The contact time is several minutes to several hours.

As the gas, the alkylene oxide alone may be used, but depending on the case, another solvent may be used in combination. Examples of such a solvent include a hydrocarbon compound having 1 to 20 carbon atoms and a halogenated hydrocarbon compound. Is available,
In particular, halogenated hydrocarbon compounds and aromatic hydrocarbon compounds are preferably used. Specifically, benzene, toluene, xylene, ethylbenzene, dichloromethane, chloroform, dichloroethane, trichloroethane, perchloroethane, etc. are exemplified. Usually, the concentration of alkylene oxide in the gas is 1 to 100%, preferably 5 to 100%.
%.

[0029]

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

Example 1 A vibrating mill equipped with four 4-liter crushing pots containing 9 kg of steel balls having a diameter of 12 mm and having a capacity of 4 liters is prepared. Under a nitrogen atmosphere, 300 g of magnesium chloride, 60 ml of tetraethoxysilane and 45 ml of α, α, α-trichlorotoluene were added to each pot.
ml was added and crushed for 40 hours. Co-ground product 300 thus obtained
g in a 5 liter flask, 1.5 liters of titanium tetrachloride and 1.5 liters of toluene are added.
The mixture was stirred for minutes, and then the supernatant was removed. Add 1.5 liters of titanium tetrachloride and 1.5 liters of toluene again,
The mixture was stirred at 100 ° C. for 30 minutes, and then the supernatant was removed. Thereafter, the solid content was repeatedly washed with n-hexane to obtain a transition metal catalyst slurry. When a part was sampled and analyzed for titanium content, the titanium content was 1.9 wt%.

Under an atmosphere of nitrogen, 40 ml of toluene, 100 mg of the above-mentioned 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 a capacity of 5 liters, and 1.5 kg of propylene and 80 g of vinylsilane were added. Plus hydrogen
After injection of 0.5N liter, polymerization was carried out at 75 ° C for 2 hours. After the polymerization, unreacted propylene was purged, the powder was taken out, and dried by filtration to obtain 480 g of powder.

The intrinsic viscosity (hereinafter abbreviated as η) was measured with a tetralin solution at 135 ° C., and measured at 10 ° C. /
When the melting point and crystallization temperature were measured as the maximum peak temperature by raising or lowering the temperature at min, the obtained powder had η of 2.35 dl / g , a melting point of 156 ° C., and a crystallization temperature of 1
It was a crystalline propylene copolymer at 20 ° C. still,
According to elemental analysis, it contained 1.3% by weight of vinylsilane units.

100 g of the obtained copolymer and 10 mg of a cyclooctadiene complex of rhodium chloride were mixed well and pressed at 240 ° C. to obtain a molded product having a thickness of 2 mm. This was put into the gas phase in an autoclave having a volume of 1 liter so as not to come in contact with the liquid.
The mixture was treated at 40 ° C. for 5 hours. Next, when the infrared absorption spectrum of the molded product was measured, an absorption was observed at about 1100 cm ^-1 and a weight increase of about 0.5% was observed.

Example 2 A propylene copolymer having an allylsilane content of 0.25 wt% was produced by polymerization in the same manner as in Example 1 except that 1 g of allylsilane was used instead of vinylsilane. Η of the copolymer is 1.85 dl / g
The extraction residue was 96.8% when extracted with boiling n-heptane for 6 hours at a melting point of 158 ° C and a crystallization temperature of 115 ° C. A molded product was prepared in the same manner as in Example 1 except that 100 g of this powder was used, and the same procedure as in Example 1 was repeated except that cyclohexene oxide was used in place of propylene oxide and the heating temperature was 100 ° C., and a weight of about 1.8% was obtained. Increase,
Similarly, absorption was observed at 1100 cm ^-1 in the infrared absorption spectrum.

[0035]

According to the present invention, a polyolefin molded product can be efficiently modified by implementing the method of the present invention, which is extremely valuable industrially.

Claims (1)

(57) [Claims] 1. An alkenylsilane / olefin copolymer and rhodium salt, a platinum salt and the following general formula : (Wherein R ¹ and R ² are the same or different and have 1 to 12 carbon atoms)
A hydride residue, n is an integer of 0 to 3, M is titanium, zirconium
Metal selected from uranium and hafnium. ) Period
A method for modifying a polyolefin molded article, comprising subjecting a molded article obtained by heat-melting and molding a catalyst selected from an alkoxy compound of a Group IVB metal to a gaseous alkylene oxide.