KR100445237B1 - Method for Preparation of Polyolefin/Clay Nanocomposite - Google Patents

Abstract

The present invention relates to a method for manufacturing a nanocomposite in which clay is dispersed on an olefin-based polymer at a nano scale, and an object of the present invention is to provide a nanocomposite having superior physical properties than that prepared by the compounding method. to be.

In the step of supporting the catalyst for olefin polymerization on the clay, the step of supporting the promoter and polymerizing the olefin to prepare the olefin-based polymer nanocomposites in which the delaminated clay is dispersed, organic treatment having a functional group with clay Clay is used, a Ziegler-Natta catalyst in which chlorine or oxychloride is bonded to titanium (Ti) or vanadium (V) as an olefin polymerization catalyst, and an organic aluminum is used as a promoter.

Description

Method for preparing olefin-based polymer nanocomposites dispersed in clay {Method for Preparation of Polyolefin / Clay Nanocomposite}

The present invention relates to a method for producing a polymer / clay nanocomposite, and more particularly, to a method for producing a nanocomposite in which clay is dispersed in an olefin polymer on a nano scale and a polyolefin resin containing the same. .

The polymer / clay nanocomposite is a polymer having a silicate layered structure that is peeled off and dispersed in a polymer matrix in nanoscale units. The polymer / clay nanocomposite has superior physical properties than a conventional polymer / clay composite in which relatively large clay particles are dispersed.

In other words, if a polymer having a silicate layer structure in a polymer resin is peeled off and dispersed in a sheet-based base unit, the tensile strength and heat distortion temperature are not only significantly increased but also impact resistance and heat resistance are not significantly impaired. Gas and liquid barrier properties, flame resistance and UV transmission resistance are higher than existing polymer / clay composites of the same clay content.

Such polymer / clay nanocomposites were conventionally manufactured by compounding, in which molten polymer is intercalated between silica silicate layers and mechanically mixed and dispersed. When the matrix polymer is nonpolar, clay exhibits a positive charge. Therefore, there is a problem that the polymer does not penetrate well between the layers.

Macromolecules, 30, 6333 (1997) and J. of Applied Polymer Science, 67, 87 (1998) include polar group-grafted polyolefin oligomers such as maleic anhydride to insert nonpolar polymers between clay silicate layers. A method of infiltrating to make an intercalated clay master batch and mixing it with a polyolefin polymer is disclosed.

However, according to this method, the polar polymer can be penetrated into the silicate layer and organicized. However, in order to completely peel off the silicate layer, it is necessary to mix it for a long time at high shear rate in the extruder. There is a concern, and there is a disadvantage in reducing the heat deformation temperature and the mechanical strength of the nanocomposite in which the oligomer added to organicize the clay is produced.

Thus, a polymerization method has been developed in which a silicate layer is peeled off by polymerizing an olefin monomer between silicate layers. International patent WO99 / 47598 discloses clay / alkyl aluminoxane by contacting clay with a promoter of alkyl aluminoxane. A method of preparing a nanocomposite by making a composite, carrying an olefin polymerization catalyst to make a clay / alkyl aluminoxane / catalyst complex, and then allowing the olefin monomer to polymerize between layers is disclosed.

However, the disadvantage that the amount of alkyl aluminoxane, which is a promoter added to impart activity to the catalyst, amounts to several thousand times the amount of catalyst, and the molecular weight of the alkyl aluminoxane is large so that it can be supported between the silicate layers. There is a disadvantage in that a pretreatment process for increasing the distance between silicates is required.

It is an object of the present invention to provide a method for producing nanocomposites in which clays are dispersed at an nanoscale in an olefinic polymer by completely peeling the silicate layer of clay and a polyolefin resin containing the same.

1 is a result of analysis by X-ray scattering analyzer (XRD), a is a result of X-ray scattering analysis of the sample of the organic montmorillonite, b is a nanoparticle prepared by polymerizing ethylene by supporting the catalyst on the organic montmorillonite X-ray scattering analysis of the complex. Where 2θ is the angle of reflection of the X-rays and I (cps: counts per second) is the intensity of the X-rays.

2 is a transmission electron microscope (TEM) of a nanocomposite master batch prepared by supporting a catalyst in organicized montmorillonite and polymerizing ethylene and a specimen prepared by compounding polyethylene in a twin screw extruder once (content of montmorillonite 5 wt%) It is a photograph.

The present invention for achieving the above object, the step of supporting the catalyst for olefin polymerization in the clay, the step of supporting the cocatalyst, and polymerizing the olefin to prepare the olefin-based polymer nanocomposites in which the clay is separated In the present invention, clay is organically treated with an organic compound having a hydroxyl group or an amine group capable of supporting a catalyst with clay, and chlorine or oxychloride is bonded to titanium (Ti) or vanadium (V) as a catalyst for olefin polymerization. Ziegler-Natta catalyst in the form, characterized in that the use of organic aluminum as a promoter.

The object of the present invention is achieved by the separation between the layers and the layers while the polyolefin is polymerized between the silicate layers of the catalyst supported clay.

Optionally, pretreatment may be carried out before loading the catalyst, which is sufficient to dry below 100 ° C. in a vacuum oven.

In organically treated clay, the clay has a layered structure and can be nanodispersed in the polymer, montmorillonite, hectorite, saponite, sauconite, sauconite, vermiculite, and margarine. The organic compound is selected from the group consisting of magnetite and kenyaite, and the organic compound is selected to have a functional group capable of fixing a catalyst by reacting with a catalyst such as a hydroxyl group and an amine group at the terminal.

In the case of using the hydroxyl group already present on the silicate layer, the catalyst may be selected from compounds that can maximize the distance between layers so that the catalyst can easily penetrate between the silicate layers. It is advantageous to use clays that have been organically treated with the compound.

An organic compound having a terminal functional group used in the organic treatment of clay is a compound having a hydroxyl group and an amine group at the terminal of the ammonium hydrocarbon compound, and a compound having a large carbon number of 8-18 having a large number of silicates to maximize the distance between silicates. This is advantageous.

As the catalyst for olefin polymerization supported between the layered structures of clay, a Ziegler-Natta catalyst in which chlorine or oxychloride is bonded to titanium (Ti) or vanadium (V) is used. That is, the present invention is characterized by using a catalyst for olefin polymerization which is generally used.

Alternatively, an organometal complex in which a metal selected from Zr, Ti, Ni, and Pd is bonded to the organic compound may be used as a catalyst. These are the same as the transition metal catalysts used in conventional olefin polymerization.

The catalyst is supported by reaction with functional groups such as hydroxyl groups or amine groups present in the hydroxyl group existing on the surface of the silicate layer of clay or between organic compounds inserted between the clay layers in order to organicize the clay. Alternatively, an organic compound having a functional group such as an amine group directly reacts with the catalyst when supporting the catalyst to serve as a carrier for the catalyst, and the organic compound without the functional group increases the silicate interlayer distance between the clays and the catalyst is present on the surface of the clay layer. It can be supported by reacting with actual machine. The catalyst supported reaction is carried out in a state in which the organicated clay is dispersed in a solvent under an atmosphere of vacuum or an inert gas.

Cocatalysts include organoaluminum or aluminum compounds including halogens, such as (C ₂ H ₅ ) ₃ Al, (C ₂ H ₅ ) ₂ AlCl, (C ₂ H ₅ ) AlCl ₂ , (tC ₄ H ₉ ) ₃ Al, (iso-C ₄ H ₉ ) ₃ Al to be used.

The cocatalyst is used 5 to 200 times, preferably 10 to 100 times the catalyst on a molar basis.

Olefins are ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene (Alpha) -olefin which has linear alkyl groups, such as these, 3-methyl-1- butene (3-methyl-1-butene), 3-methyl-1- pentene (3-methyl-1-pentene), 4-methyl-1 ? -Olefins having branched alkyl groups such as -pentene (4-methyl-1-pentene) and 4-methyl-1-hexene; vinylcyclopentane and vinylcyclohexane (alpha) -olefin which has cyclic alkyl groups, such as (vinylcyclohexane) and 5-vinyl-2-norbornene, and the olefin which has aromatic alkyl groups, such as styrene and vinylnaphthalene, 1,4-hexadiene (1,4-hexadiene), 1,5-hexadiene (1,5-hexadiene), 4-methyl-1,4-hexadiene (4-methyl-1,4-hexadiene), It is used by selecting one or two or more from non-conjugated diene alkyl compounds such as 1,7-octadiene (1,7-octadiene) and copolymers thereof.

The olefin polymerization reaction may be based on a gas phase reaction, and may be an aliphatic hydrocarbon compound such as n-hexane or n-heptane, or an aromatic hydrocarbon compound such as toluene or benzene as a solvent. You may react inside.

The polyolefin resin of desired physical properties can be obtained by mixing the polyolefin resin according to a conventional method using the clay-dispersed olefin polymer nanocomposite prepared through the above manufacturing process as a master batch.

The configuration of the present invention will be clearer through the following examples.

<Example 1>

1. Sample

(1) Organicated Clay: Montmorillonite (Closisite 30B from Southern Clay Products Inc., USA) 5,000 with methyl tallow bis-2-hydroxyethyl quaternary ammonium chloride Mg

(2) solvent: toluene 200ml

(3) Catalyst for ethylene polymerization: TiCl ₄ 0.7 mmol

(4) Cocatalyst: Al (Et) ₃ 14 mmol (Al / Ti = 20)

2. Experimental method

(1) Support of catalyst

In the high-pressure reactor (1 L) in an argon gas (inert gas) atmosphere, the organicized clay was dispersed in a solvent, and the catalyst was added to the reactor and supported on the organicized clay for 1 hour at 30 ° C., followed by adding a promoter to 30 It was reacted for a minute.

(2) polymerization

Through the assumption of (1), ethylene was polymerized for 1 hour at 30 DEG C and 4 atm using clay loaded with a catalyst and a promoter.

3. Results

20.2 g of polyethylene at a melting point of 131.2 ° C. was polymerized, and the clay used as a catalyst was subjected to a wide-angle X-ray scattering analyzer (XRD) (Mac Science, MXT-108, CuKα X-ray, 30 kV, 40 mA, sampling width: 0.02 deg.). As a result, as shown in FIG. 1, it was confirmed that no peak appeared and the crystal structure was completely broken (the layer was completely peeled off).

In addition, the synthesized product was mixed with polyethylene so that the content of clay was 5wt% and compounded once with a twin screw extruder to observe the specimen by transmission electron microscopy (TEM), as shown in Figure 2, It was confirmed that the silicate layer was completely peeled off.

<Example 2>

Propylene was polymerized for 1 hour using the catalyst supported in Example 1.

15.3 g of polypropylene having a melting point of 160.5 ° C. was polymerized, and clay Cloisite 30B was analyzed by X-ray scattering analyzer, and as in Example 1, no peak was observed, indicating that the clay was completely peeled off.

<Example 3>

Montmorillonite (Closisite 20A from Southern Clay Products Inc., USA; Organication Concentration; 95meq / 100g) 5,000 with organicated clay dimethyl dihydrogenated tallow quaternary amonium chloride 5,000 MG was dispersed in 200 ml of toluene, 1.3 mmol of TiCl ₄ catalyst was added thereto, and the mixture was supported at 30 ° C. for at least 1 hour, 26.0 mmol of Al (Et) ₃ was added and reacted for at least 30 minutes. The reaction was carried out at 8 atmospheres for 1 hour.

32.7 g of ethylene at a melting point of 131 ° C. was polymerized, and clay Cloisite 20A was analyzed by X-ray scattering analyzer. As a result, it was confirmed that the silicate layer was opened by ethylene polymerization due to the decrease in the scattering angle of the peak. It was not completely peeled off.

<Example 4>

Disperse 10.0 g of montmorillonite (Closisite 30B from Southern Clay Products Inc., U.S.A.) organicized with methyl tallow bis-2-hydroxyethyl quaternary ammonium chloride in 500 ml of toluene Then, 2.0 mmol of TiCl ₄ catalyst was added thereto, and the mixture was supported at 30 ° C. for at least 1 hour, and 30.0 mmol of Al (Et) ₃ was added for reaction for at least 30 minutes. The reaction was carried out for 1 hour at. As a result, 35.7 g of poly (1-butene) was obtained at a melting point of 130 ° C., and a wide angle X-ray scattering analyzer analysis showed that montmorillonite was completely peeled off.

Example 5

Disperse 5.0 g of montmorillonite (Closisite 30B from Southern Clay Products Inc., USA) organicized with methyl tallow bis-2-hydroxyethyl quaternary ammonium chloride in 200 ml of toluene 1.0 mmol of TiCl ₄ catalyst was added thereto, and the mixture was supported at 30 ° C. for at least 1 hour, and 15.0 mmol of (C ₂ H ₅ ) ₂ AlCl was added for reaction for 30 minutes or longer, followed by 40 g of 4-methyl-1-pentene (4- methyl-1-pentene) was injected and reacted at a reaction temperature of 50 ° C. for 1 hour. As a result, 19.8 g of poly (4-methyl-1-pentene) having a melting point of 240.5 ° C. was obtained, and a wide angle X-ray scattering analyzer analysis showed that the montmorillonite layer was completely peeled off.

Comparative Example 1

The reaction was carried out under the same conditions as in Example 1 using unorganized montmorillonite (Closisite Na ⁺ of Southern Clay Products Inc., USA), whereby 21.9 g of polyethylene having a melting point of 133 ° C. was obtained. It was confirmed that the silicate layer of montmorillonite did not peel off, and that polyethylene polymerization occurred mostly outside the montmorillonite silicate layer.

The polyolefin resin having excellent physical properties is obtained by mixing polyolefin using the olefin polymer nanocomposite in which clay prepared by the above method is dispersed as a master batch.

The blending ratio of the master batch and the polyolefin resin depends on the desired physical properties, but if the content of clay is 1 to 10% by weight, the transparency may not be significantly impaired.

According to the present invention, an olefin-based polymer nanocomposite in which clay is dispersed on a nanoscale in an olefin-based polymer having superior physical properties than that prepared by the compounding method alone can be prepared. It is possible to prepare a resin having excellent physical properties such as tensile strength and heat deformation temperature without using.

Claims (8)

In the step of supporting the catalyst for olefin polymerization on the clay, the step of supporting the cocatalyst, and in the preparation of the olefin polymer nanocomposites in which the delaminated clay is dispersed by polymerizing olefin, the catalyst may be supported by clay. Ziegler-Natta catalyst using a clay organicated with an organic compound having a hydroxy group or an amine group at the end, and chlorine or oxychloride bonded to titanium (Ti) or vanadium (V) as a catalyst for olefin polymerization. The method of producing an olefin-based polymer nanocomposite in which clay is dispersed, which comprises using organic aluminum as a promoter. The method of claim 1, wherein the clay is montmorillonite, hectorite, saponite, souconite, vermiculite, margarite, Kenyaite, characterized in that clay dispersed olefin polymer nanocomposite manufacturing method. The method of claim 1, wherein the olefin polymerization catalyst is dispersed in clay, characterized in that selected from the organic compound (organometal complex) in which a metal selected from Zr, Ti, Ni, Pd is bonded to the organic compound (organic compound) Olefin-based polymer nanocomposite manufacturing method. The method of claim 1, wherein the organoaluminum used as a promoter is (C ₂ H ₅ ) ₃ Al, (C ₂ H ₅ ) ₂ AlCl, (C ₂ H ₅ ) AlCl ₂ , (tC ₄ H ₉ ) ₃ Al, (iso-C ₄ H ₉ ) A method for producing clay dispersed olefin polymer nanocomposite, characterized in that selected from ₃ Al. The method of claim 1, wherein the amount of cocatalyst used is 10 to 100 times the amount of the catalyst on a molar basis. The olefin of claim 1 wherein the olefin is ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 3-methyl-1-butene, 3-methyl-1-pentene, 4- Methyl-1-pentene, 4-methyl-1-hexene, vinylcyclopentane, vinylcyclohexane, 5-vinyl-2-norbornene, styrene, vinylnaphthalene, 1,4-hexadiene, 1,5-hexadiene , 4-methyl-1,4-hexadiene, 1,7-octadiene is selected from 1 or 2 or more clay-dispersed olefin polymer nanocomposite manufacturing method. The polyolefin resin containing the olefin type polymer nanocomposite which the clay manufactured by the method of any one of Claims 1-6 disperse | distributed. The polyolefin resin according to claim 7, wherein the content of clay in the polyolefin resin is 1 to 10% by weight.