JP3213419B2 - Modification method of polyolefin - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for modifying a polyolefin. More specifically, the present invention relates to a method for modifying a polyolefin, which comprises treating a polyolefin copolymerized with alkenylsilene with an alkylene oxide in the presence of a specific catalyst.

[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]

On the other hand, a method of treating a copolymer of alkenylsilane and olefin with an alkylene oxide in the presence of a catalyst is effective.
There is a problem that the catalyst used in this method is expensive.

It is desirable to search for an inexpensive catalyst.

[0005]

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

That is, in the present invention, a copolymer of an alkenylsilane and an olefin is contact-treated with an alkylene oxide in the presence of a catalyst to give the copolymer an alkylene oxide.
In the method of modifying polyolefin by fuft polymerization ,
This is a method for modifying a polyolefin, which comprises using a metallocene compound or a metallocene compound and an organometallic compound as a catalyst.

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):

[0008]

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):

[0010]

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 trichloride 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. In addition, 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. As the alkyl group, a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group and the like can be used. 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 alkenylsilane and olefin is usually about 0.01 to 30 mol%, preferably about 0.01 to 30 mol%, from the viewpoint of increasing the degree of crosslinking.
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.

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 which is important in the present invention includes at least one cyclopentadienyl group or a derivative thereof, for example, an alkyl-substituted cyclopentadienyl group, an indenyl group, a hydrogenated indenyl group, a fluorenyl group, or a group consisting of A metal compound having a ligand bonded by an alkylene residue, a silylene residue, or the like as a ligand, particularly preferably a metal compound of Group IVB of the periodic table, and a titanium, zirconium, or hafnium compound can be preferably used. Here, further, aluminum, organometallic compounds of magnesium, alkyl aluminum having 1 to 12 carbons, alkyl magnesium having 1 to 12 carbons, 6 to 6 carbons
It is also possible to use 12 allylmagnesium and the like together.

In the present invention, examples of the alkylene oxide include compounds represented by the following general formula (3) having a three-membered 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 contact between the alkenylsilane-olefin copolymer and the alkylene oxide and the catalyst can be carried out after or before the molding of the alkenylsilane-olefin copolymer. In some cases, the cross-linking reaction proceeds by contact, so that it is preferable to contact the catalyst and the alkylene oxide after molding into a desired shape.

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.

A mixture of a copolymer of an alkylene oxide and an olefin, a polyolefin optionally mixed, a filler and the like is formed prior to contact with the following catalyst. 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, alkylene oxide can be grafted at a high concentration when mixed so that the alkenylsilane concentration in the molded product becomes 0.01 to 20 mol%, preferably 0.1 to 10 mol%.

In the present invention, the contact of the copolymer of alkenylsilane and olefin, the alkylene oxide, and the catalyst is carried out by dissolving the catalyst and the alkylene oxide in a solution in which the alkylene oxide itself can be used as a solvent. Is generally carried out by contacting a molded product of the copolymer (a), but depending on the case, it is also possible to heat and mix the three. The contact temperature when contacting with a solution is from room temperature to 150
° C and the contact time is several minutes to several hours. Since the contact temperature greatly affects the permeation of the catalyst, appropriate conditions are selected according to the characteristics of the molded product. The temperature at which the three are heated and melted and brought into contact is generally at the temperature at which the copolymer used or the polymer is melted, usually at 150 to 350 ° C.

In the case of contacting with a solution, as the solvent to be used, specifically, a hydrocarbon compound having 1 to 20 carbon atoms and a halogenated hydrocarbon compound can be used, and in particular, a halogenated hydrocarbon compound, an aromatic hydrocarbon Compounds are preferably used. Specifically, benzene, toluene, xylene, ethylbenzene, dichloromethane, chloroform, dichloroethane, trichloroethane, perchloroethane and the like are exemplified. Usually, alkylene oxide is used so as to have a concentration of 1 to 100%, preferably 5 to 100%. You. The catalyst is mixed so that the concentration of the catalyst in the solution is 0.1 to 10,000 ppm. The amount of the solution used may be any amount that can immerse the molded article.

When the three components are mixed by heating and melting, they are mixed so that the concentration of the catalyst in the mixture becomes 0.1 to 10,000 ppm.
Generally, the alkylene oxide will be 0.1-5% of the total mixture.

[0030]

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%.

In a 5 liter autoclave, under a nitrogen atmosphere, 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, 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./D using a differential thermal analyzer.
The melting point and crystallization temperature were measured as the maximum peak temperature by raising or lowering the temperature by min. The obtained powder was a crystal having η of 2.35 dl / g , melting point of 156 ° C, and crystallization temperature of 120 ° C. Propylene copolymer.
According to elemental analysis, it contained 1.3 wt% of a vinylsilane unit.

100 g of the obtained copolymer was press-molded at 240 ° C. to obtain a molded product having a thickness of 2 mm. This molded product was immersed in a solution of dicyclopentadienyl zirconium dichloride in cyclohexene oxide at a concentration of 1 g / liter and contacted at 80 ° C. for 3 hours. Next, the surface of the molded article was washed with toluene and the infrared absorption spectrum was measured. As a result, an absorption was observed at about 1100 cm ^-1 and a weight increase of about 0.6% was observed.

Example 2 Polymerization was carried out in the same manner as in Example 1 except that 1 g of allylsilane was used instead of vinylsilane, to produce a propylene copolymer powder having an allylsilane content of 0.25 wt%. Η of the copolymer is
1.85 dl / g , melting point 158 ° C, crystallization temperature 115 ° C,
The percentage of extraction residue when extracted with boiling n-heptane for 6 hours
96.8%. Except that 100 g of this powder was used, a molded article was made in the same manner as in Example 1 except that the molded article was used, and the weight was increased by about 0.2%. Similarly, 1100 cm ^-1 was measured in the infrared absorption spectrum. Absorption was observed.

[0036]

According to the method of the present invention, a graft polymer can be efficiently obtained using an inexpensive catalyst, which is extremely valuable industrially.

Claims (1)

(57) [Claims] 1. A copolymer of the alkenylsilane and olefin in contact treatment with an alkylene oxide in the presence of a catalyst the
A method for modifying a polyolefin by graft polymerization of an alkylene oxide onto a copolymer, wherein a metallocene compound or a metallocene compound and an organometallic compound are used as a catalyst.