KR100665130B1 - Method for preparing epoxy nanocomposites containing vapor-grown carbon nanofibers and nanocomposites prepared therefrom - Google Patents

Abstract

According to the present invention, after dispersing by physically mixing 0.1 to 5.0 parts by weight of vapor-grown carbon nanofibers as a reinforcing agent with respect to 100 parts by weight of epoxy matrix resin, a hardening agent is added to the dispersed mixture and cured. It relates to a method for producing an epoxy nanocomposite material containing fibers and the nanocomposite material produced therefrom.

The manufacturing method of the present invention physically mixes the vapor-grown carbon nanofibers with the epoxy matrix resin without using a solvent, so that the degree of dispersion of the vapor-grown carbon nanofibers in the matrix resin is better than that with the solvent, and thus, Since perfect mixing can be realized, it is possible to prepare nanocomposites having excellent mechanical strength, friction and wear characteristics at room temperature, and excellent thermal properties at high temperatures. In addition, compared to the carbon nanotubes conventionally used for improving the physical properties of the epoxy resin is economical and manufactured using a small amount, it is effective in reducing the manufacturing cost of the nanocomposite material.

Description

METHOD FOR MANUFACTURING EPOXY NANOCOMPOSITE MATERIAL CONTAINING VAPOR-GROWN CARBON NANOFIBERS AND ITS PRODUCTS THEREBY}

Figure 1 shows the thermal expansion coefficient of the nanocomposite according to the content of vapor-grown carbon nanofibers of the present invention,

Figure 2 shows the impact strength, which is a mechanical property of the nanocomposite according to the content of vapor-grown carbon nanofibers of the present invention,

Figure 3 shows the interlaminar fracture toughness, which is a mechanical property of nanocomposites according to the content of vapor-grown carbon nanofibers of the present invention,

Figure 4 shows the frictional force of the nanocomposite according to the content of vapor-grown carbon nanofibers of the present invention,

Figure 5 shows the friction coefficient of the nanocomposite according to the content of the gas phase growth carbon nanofibers of the present invention,

Figure 6 shows the wear loss of the nanocomposite according to the content of the gas phase growth carbon nanofibers of the present invention.

The present invention relates to a method for producing an epoxy nanocomposite material containing vapor-grown carbon nanofibers and a nanocomposite material prepared therein, and more particularly to a vapor-grown carbon nanofiber in an epoxy matrix resin. By physically mixing without using a solvent and performing under optimum curing conditions, the present invention relates to an epoxy nanocomposite material containing vapor-grown carbon nanofibers, which has excellent mechanical strength, friction and abrasion characteristics at room temperature, and thermal properties at high temperatures. will be.

With the development of the modern industrial society, the development of new materials having superior properties to existing materials has been required in various fields, and many researches on nanocomposite materials are representative of the recent development of nanotechnology. As a nanocomposite material, epoxy resin, one of thermosetting polymers, has excellent electrical properties, adhesive strength, tensile strength, elastic modulus, heat resistance, and chemical resistance, so it is a high performance structural material, coating material, housing coating material, PCB plate, artificial joint, medical and engineering It is widely used for applications such as fine parts, aerospace and aviation parts, semiconductor encapsulation materials, battery insulation materials, adhesives, matrixes of composite materials, coating compounds, and the like.

However, these epoxy resins have the disadvantage of being easily broken even by light impact due to their low mechanical properties, high coefficient of thermal expansion and high density of crosslinking, so that many studies on blends with reinforcing agents to improve the thermal and mechanical properties of epoxy resins have been made. It has been going on. As an example, in International Patent Nos. 2005-28174 and US 2003-3270, in order to improve physical properties such as thermal and mechanical properties of an epoxy resin, which is a thermosetting resin, various types of reinforcing agents or functional groups are introduced and mixed. A method of making a material is disclosed.

In general, reinforcing agents for the production of nanocomposites, nano-sized layered materials such as layered silica and clays usually have very high aspect ratios, and once dispersed uniformly in the polymer matrix, the mechanical, thermal and gas permeability of the polymer And various physical properties such as flame retardancy can be greatly improved. On the other hand, nanocomposites filled with these layered inorganic compounds lack physical properties such as electrical conductivity, optical and dielectric properties, and many studies have been conducted on nanocomposites using carbon black and metal powder as fillers for nanocomposites. . However, the carbon black or metal powder is required to have a high content in order to be mixed with the polymer matrix to exhibit sufficient conductivity, which has been pointed out as another problem causing a decrease in the mechanical properties of the prepared polymer composite material. Therefore, in order to improve mechanical properties, carbon nanotubes / epoxy composites are prepared by dissolving and dispersing carbon nanotubes in ethanol by varying the content of carbon nanotubes, and then dispersing carbon nanotubes and ethanol well in ultrasonic polymer with ultrasonic waves. Techniques for producing carbon nanotube-reinforced thermosetting matrix resin nanocomposite compositions which have been improved by toughening them in a mold have been known [YS Song and JR You., Carbon , 2005 , 43 , 1378].

Recently, vapor-grown carbon nanofibers, which are one of carbon fibers, have been proposed. The vapor-grown carbon nanofibers have a high aspect ratio, and the structure has a structure in which the graphite is arranged in a ring shape around the fiber and is very chemically. Stable. Particularly, vapor-grown carbon nanofibers act as a reinforcing agent, but because of the graphite component, they have excellent thermal conductivity and can be applied to friction and abrasion fields. It is expected to have superior properties in comparison to other materials including metals.

Thus, the present inventors physically mixed vapor-grown carbon nanofibers with an epoxy matrix resin in order to solve the conventional problems as part of an effort to provide a nanocomposite material of improved physical properties using an epoxy resin, the gas phase in the matrix resin Epoxy nanocomposite material with excellent impact strength, low coefficient of thermal expansion and abrasion loss, as the dispersion degree of grown carbon nanofibers is better than that of solvents, so that perfect mixing in the polymer is achieved and performed under optimum curing conditions. By providing the present invention, the present invention has been completed.

An object of the present invention is to provide a method for producing an epoxy nanocomposite containing the vapor-grown carbon nanofibers.

Another object of the present invention is to provide an epoxy nanocomposite material containing the vapor-grown carbon nanofibers prepared by the above production method.

According to the present invention, 0.1 to 5.0 parts by weight of vapor-grown carbon nanofibers are physically mixed and dispersed with respect to 100 parts by weight of an epoxy matrix resin, and then a curing agent is added to the dispersed mixture and 5 ° C. / at a temperature of 70 to 200 ° C. It provides a method for producing an epoxy nanocomposite material containing vapor-grown carbon nanofibers, which is heated to min and cured for 150 to 210 minutes.

The average diameter of the vapor-grown carbon nanofibers is 80-220 nm, the length is 5-25 μm, and the tensile strength is 0.1-3.5 GPa.

In the above, the curing agent is preferably added in a 1: 1 equivalent ratio to the mixture. Preferably, the curing is performed in one step for 20 to 30 minutes at 70 to 100 ° C. at a heating rate of 5 ° C./min, and 140 to 160. 2-step curing at 90 ° C. for 90-120 minutes and 3-step curing at 180-200 ° C. for 40-60 minutes.

In addition, the present invention provides a nanocomposite material produced by the method for producing an epoxy nanocomposite containing the vapor-grown carbon nanofibers.

The nanocomposite material of the present invention exhibits a glass transition temperature of 110 to 160 ℃, the thermal expansion coefficient of the nanocomposite is 60 ~ 80㎛ / m ℃ before the glass transition temperature, 180 ~ 215㎛ / m ℃ after the glass transition temperature.

The nanocomposite has an impact strength of 50 to 130 kgf · cm / cm and an interlaminar fracture toughness of ² to 10 MPa · m ^1/2 .

At room temperature and in a non-lubricated state of the nanocomposite of the present invention, the frictional force is 0.3 to 1.1 N, the coefficient of friction is 0.05 to 0.30 µ, and the wear loss is 0.1 to 0.3 mm.

Hereinafter, the present invention will be described in detail.

According to the present invention, 0.1 to 5.0 parts by weight of vapor-grown carbon nanofibers are physically mixed and dispersed with respect to 100 parts by weight of an epoxy matrix resin, and then a curing agent is added to the dispersed mixture and 5 ° C. / at a temperature of 70 to 200 ° C. It provides a method for producing an epoxy nanocomposite material containing vapor-grown carbon nanofibers, which is heated to min and cured for 150 to 210 minutes.

The present invention is characterized by physically mixing gaseous growth carbon nanofibers in an epoxy matrix resin without using a solvent, so that the degree of dispersion of the gaseous growth carbon nanofibers in the matrix resin is superior to that in which a solvent is used. Since the mixing can be implemented, the nanocomposite material having excellent mechanical strength, friction and abrasion properties at room temperature and excellent thermal properties at high temperatures is manufactured.

Since the epoxy resin has excellent electrical properties, adhesive strength, tensile strength, elastic modulus, mechanical strength, heat resistance, and chemical resistance, it has excellent thermal characteristics even at high temperatures, and thus has little loss of physical properties due to heat. Although an epoxy resin is demonstrated in this invention, it is applicable to other thermosetting resins. In particular, in the present invention, in order to increase the dispersibility between the epoxy resin and the reinforcing agent, it is more preferable to use an epoxy matrix resin having a high crosslinked structure and heat resistance. At this time, the viscosity of the epoxy matrix resin 11500-13500 cps is preferable.

As the reinforcing agent used to improve physical properties of the epoxy resin, the present invention uses vapor-grown carbon nanofibers. In particular, the average diameter of the vapor-grown carbon nanofibers of the present invention is 80-220 nm, the length is 5-25 탆, and the tensile strength is 0.1-3.5 GPa. Nickel powder, gold powder, copper powder, metal alloy powder, carbon powder, graphite powder, carbon black, carbon fiber, etc. may be used in addition to the vapor-grown carbon nanofibers.

At this time, 0.1-5.0 weight part of gaseous growth carbon nanofibers are mixed as a reinforcing agent with respect to 100 weight part of epoxy matrix resins. In the above, when the content of the gaseous growth carbon nanofibers is less than 0.1 parts by weight, it is insufficient to improve the physical properties of the epoxy resin, while when exceeding 5.0 parts by weight, the gaseous growth carbon nanofibers in the epoxy matrix resin is sufficiently It is difficult to disperse, so it is uneconomical and mechanical properties and wear loss can be large.

In addition, the method for producing a nanocomposite of the present invention, when mixing the reinforcing agent in the epoxy matrix resin, can be mixed while heating the reinforcing agent to about 80 ℃ with agitation for even dispersion. At this time, when the viscosity of the epoxy matrix resin is high, it is difficult to completely mix and evenly disperse the reinforcing agent, and eventually have a great influence on the mechanical properties of the nanocomposite.

In the method for producing a nanocomposite material of the present invention, after physically mixing the vapor-grown carbon nanofibers as a reinforcing agent with respect to the epoxy matrix resin, a curing agent is added, and the heating rate is 5 ° C / min. Nanocomposites are prepared by one step curing at 20 to 30 minutes, two step curing at 140 to 160 ° C., 90 to 120 minutes, and three step curing at 180 to 200 ° C. for 40 to 60 minutes. The three-step curing cycle under these conditions, i.e. the glass transition temperature (40 ° C.) of the unreacted reactant consisting of a mixture initially mixed with epoxy, and the maximum glass transition temperature (180) seen in a fully cured mixture system of epoxy. By setting the curing conditions on the basis of the region near ° C), it is advantageous in terms of processing and economics compared to other regions.

The curing agent is preferably a conventional aromatic amine curing agent, for example DGEBA (diglycidylether of bisphenolA) is a typical general-purpose epoxy resin having an epoxy group at both end groups and diaminodiphenyl methane (DDM, diaminodiphenyl methane) as an aromatic amine curing agent , Diaminodiphenyl sulfone (DDS, diaminodiphenyl sulphone) is mixed with an equivalent ratio of 1: 1 to cure. More preferably diaminodiphenyl methane (DDM) is used.

In addition, after physically mixing and dispersing vapor-grown carbon nanofibers in an epoxy matrix resin, and adding a curing agent to the dispersed mixture, rapid curing occurs at a temperature higher than the melt-mixing so that the reinforcing agent of vapor-grown carbon nanofibers is completely dissolved. The production of nanocomposites is difficult because the molten mixture has to be put into the mold quickly.

The present invention provides a nanocomposite material produced by the method for producing an epoxy nanocomposite containing the vapor-grown carbon nanofibers.

In the nanocomposite of the present invention, the glass transition temperature increases as the content of the vapor-grown carbon nanofiber increases, indicating a glass transition temperature of 110 to 160 ° C., and the thermal expansion coefficient of the nanocomposite is 60 to 80 μm / m before the glass transition temperature. ℃, and after the glass transition temperature of 180 ~ 215㎛ / m ℃, the thermal expansion coefficient was confirmed that the higher the content of the gas phase growth carbon nanofibers ( Fig. 1 ).

In addition, the impact strength and interlaminar fracture toughness of the nanocomposite increased as the content of the vapor-grown carbon nanofibers increased, and the impact strength of the nanocomposite was 50-130 kgf · cm / cm, and the interlaminar fracture toughness of 2-10 MPa · m ^{1 /. 2} ( FIGS. 2 and 3 ).

Since the nanocomposite material of the present invention contains the vapor-grown carbon nanofibers, the frictional force, the coefficient of friction, and the wear loss are significantly lowered. 0.3 to 1.1 N, a coefficient of friction of 0.05 to 0.30 µ, and a wear loss of 0.1 to 0.3 mm ( Figs. 4 to 6 ).

Hereinafter, the present invention will be described in more detail with reference to Examples.

This embodiment is intended to illustrate the present invention in more detail, and the scope of the present invention is not limited to these examples.

<Example 1>

Vapor-grown carbon nanofibers (Showa Denk) having a diameter of 100 to 200 nm, a length of 10 to 20 μm, and a tensile strength of 1 to 3 GPa were dried in a vacuum oven at 70 ° C. for 24 hours to remove moisture and residual solvent. Thereafter, to the difunctional epoxy resin (DGEBA) (Kukdo Chemical YD-128, EEW = 185 to 190 g / mol, density 1.16 g / cm), physically mixed in a weight ratio of 100: 0.1, to the mixture, Diaminodiphenyl methane (DDM), a curing agent, was added in a 1: 1 equivalent ratio, followed by physical mixing and stirring using a mechanical mixer, and then the temperature rising rate was 5 ° C / min for 30 minutes at 70 ° C, 120 minutes at 140 ° C, and Epoxy nanocomposites containing vapor-grown carbon nanofibers were prepared by curing in a curing oven at 180 ° C. for 60 minutes.

<Example 2>

Vapor-grown carbon nanofibers (Showa Denk) having a diameter of 100 to 200 nm, a length of 10 to 20 μm and a tensile strength of 1 to 3 GPa were dried in a vacuum oven at 70 ° C. for 24 hours to remove moisture and residual solvent. After removal, except physically mixed with a bifunctional epoxy resin (DGEBA) (Kukdo Chemical YD-128, EEW = 185-190 g / mol, density 1.16 g / cm) at a weight ratio of 100: 0.5, In the same manner as in Example 1 to prepare an epoxy nanocomposite containing the vapor-grown carbon nanofibers.

<Example 3>

Vapor-grown carbon nanofibers (Showa Denk) having a diameter of 100 to 200 nm, a length of 10 to 20 μm, and a tensile strength of 1 to 3 GPa were dried in a vacuum oven at 70 ° C. for 24 hours to remove moisture and residual solvent. After the bifunctional epoxy resin (DGEBA) (Kukdo Chemical YD-128, EEW = 185 to 190 g / mol, density 1.16 g / cm), except that physically mixed at a weight ratio of 100: 1, In the same manner as in Example 1, an epoxy nanocomposite material containing vapor-grown carbon nanofibers was prepared.

<Example 4>

Vapor-grown carbon nanofibers (Showa Denk) having a diameter of 100 to 200 nm, a length of 10 to 20 μm, and a tensile strength of 1 to 3 GPa were dried in a vacuum oven at 70 ° C. for 24 hours to remove moisture and residual solvent. After, the above-mentioned difunctional epoxy resin (DGEBA) (Kukdo Chemical YD-128, EEW = 185-190 g / mol, density 1.16 g / cm) was mixed except that it was physically mixed in a weight ratio of 100: 2. In the same manner as in Example 1, an epoxy nanocomposite material containing vapor-grown carbon nanofibers was prepared.

Comparative Example 1

Diaminodiphenyl methane (DDM) as a curing agent in bifunctional epoxy resin (DGEBA) (Kukdo Chemical YD-128, EEW = 185 to 190 g / mol, density 1.16 g / cm) without adding vapor-grown carbon nanofibers Was added in a 1: 1 equivalent ratio to cure to prepare a pure epoxy composition.

Experimental Example 1 Measurement of Thermal Expansion Coefficient

The thermal expansion coefficient, which is a thermal property of the epoxy nanocomposite material containing the vapor-grown carbon nanofibers prepared in Examples 1 to 4, was measured.

At this time, the thermal expansion coefficient was set to a temperature increase rate of 10 ° C / min in a temperature range of 30 to 300 ° C. under a nitrogen atmosphere using a thermomechanical analyzer (model name Q400 manufactured by TA Instruments), and the thermal expansion before and after the glass transition temperature (Tg). The thermal expansion coefficient was measured. The measurement results are shown in Table 1 and FIG. 1.

Measurement Results of Glass Transition Temperature According to Vapor Content of Carbon Nanofibers division Glass transition temperature (℃) Comparative Example 1 117.44 Example 1 117.33 Example 2 123.57 Example 3 128.95 Example 4 154.01

From Table 1, the epoxy nanocomposite material containing the vapor-grown carbon nanofibers prepared in Examples 1 to 4 exhibits a glass transition temperature in the range of 110 to 160 ° C, depending on the content of the vapor-grown carbon nanofibers. In addition, the glass transition temperature increased as the content of vapor grown carbon nanofibers increased.

In addition, as shown in Figure 1, it was confirmed that the thermal expansion coefficient is lowered as the content of the vapor-grown carbon nanofiber increases, the thermal expansion coefficient before the glass transition temperature is 60 ~ 80㎛ / m ℃, after the glass transition temperature The coefficient of thermal expansion was found to be 180 to 215 µm / m ° C. From the above results, the glass transition temperature seems to increase as the content of the carbon nanofibers increases as the carbon nanofibers decrease the fluidity of the polymer chain through interaction with the epoxy resin, and as the carbon nanofibers are dispersed in the epoxy resin, the epoxy Absorption of heat introduced into the internal structure reduces the internal stress and crack incidence, which in turn reduces the coefficient of thermal expansion.

Experimental Example 2 Measurement of Mechanical Properties

The epoxy nanocomposites containing vapor-grown carbon nanofibers prepared in Examples 1 to 4 were measured for their mechanical properties, impact strength and interlaminar fracture toughness. In addition, a comparative experiment was carried out on the pure epoxy composition containing no vapor-grown carbon nanofibers prepared in Comparative Example 1.

1. Impact strength measurement

The impact strength of the epoxy nanocomposite material containing the vapor-grown carbon nanofibers prepared in Examples 1 to 4 was measured using a drop impact tester (Large diameter tech, model name: DTI-605). At this time, the highest falling height was 1 m, and the load was fixed at 2 kg. The results are shown in FIG.

As shown in Figure 2, when the vapor-grown carbon nanofibers are contained than the results of Comparative Example 1 for the pure epoxy composition containing no vapor-grown carbon nanofibers, more preferably the content of the vapor-grown carbon nanofibers is As it increased, the impact strength increased. In this case, the average impact strength of the epoxy nanocomposite material containing the vapor-grown carbon nanofibers prepared in Examples 1 to 4 was 50 to 130 kgf · cm / cm.

2. Measurement of interlaminar fracture toughness

For the epoxy nanocomposite material containing the vapor-grown carbon nanofibers prepared in Examples 1 to 4, the critical stress intensity factor (K _IC ) is a universal testing machine according to the ASTM 399 silver of the prepared nanocomposite material. The measurement was performed using a single edge notch-three point bending method using (# 1125, Lloyd LR 5k, UTM). At this time, the notch depth of the specimen is fixed at 1/2 of the thickness, the ratio of span-to-depth is 4: 1, and the cross-head speed is adjusted to 1 mm / min. It was.

Figure 3 is a result of measuring the interlaminar fracture toughness, when the vapor-grown carbon nanofibers are contained more preferably than the results of Comparative Example 1 for the pure epoxy composition containing no vapor-grown carbon nanofibers, more preferably the vapor-grown carbon nanofibers As the content of was increased, the interlaminar fracture toughness increased. In this case, the average interlaminar fracture toughness of the epoxy nanocomposite containing vapor-grown carbon nanofibers prepared in Examples 1 to 4 was 2 to 10 MPa · m ^1/2 .

Experimental Example 3 Measurement of Friction and Wear

For the epoxy nanocomposite material containing the vapor-grown carbon nanofibers prepared in Examples 1 to 4, friction and wear characteristics were measured. In addition, a comparative experiment was carried out on the pure epoxy composition containing no vapor-grown carbon nanofibers prepared in Comparative Example 1.

With respect to the epoxy nanocomposite material containing the vapor-grown carbon nanofibers prepared in Examples 1 to 4, a sliding contact type tester having a ball-on-disk shape under atmospheric conditions (PD-102, R & B) was used to measure the friction and wear characteristics. At this time, the specimen was prepared in the form of a disk with a diameter of 30 mm and a thickness of 10 mm, and set the speed of the friction rotating plate at 500 rpm at room temperature and no lubrication to give a fixed load of 3 kg of constant weight to the ball and disk contact surface. Measured after addition.

As a result, the frictional force, friction coefficient and wear loss according to the content of the vapor-grown carbon nanofibers are shown in FIGS. 4 to 6.

From the results of FIGS. 4 to 6, the epoxy nanocomposite material containing the vapor-grown carbon nanofibers prepared in Examples 1 to 4 has significantly lower frictional force, coefficient of friction, and abrasion loss from the vapor-grown carbon nanofibers. It was decreased as the content of vapor-grown carbon nanofibers increased.

More specifically, the frictional force decreased as the content of vapor-grown carbon nanofibers increased, and the average frictional force of the epoxy nanocomposite containing the vapor-grown carbon nanofibers prepared in Examples 1 to 4 was 0.3 at room temperature and without lubrication. It was -1.1 N (FIG. 4). At this time, the coefficient of friction was 0.05 to 0.30 mu (Fig. 5).

In addition, the wear loss of the epoxy nanocomposite material containing the vapor-grown carbon nanofibers prepared in Examples 1 to 4 is 0.3 mm or less, more preferably 0.1 to 0.3 mm, and as the content of the vapor-grown carbon nanofibers increases, Wear loss was significantly reduced (FIG. 6).

As described above, the present invention

First, by physically mixing vapor-grown carbon nanofibers in an epoxy matrix resin and dispersing them in a polymer, they are produced under optimum curing conditions, thereby producing a vapor-grown carbon nanofiber that can solve the conventional problem of using a solvent. To provide a method for producing an epoxy nanocomposite containing,

Second, the production method of the present invention was able to provide an epoxy nanocomposite material excellent in mechanical properties, friction and wear properties by the addition of a small amount of vapor-grown carbon nanofibers,

Third, the vapor-grown carbon nanofibers of the present invention are economical compared to the carbon nanotubes used for improving the physical properties of epoxy resins and used in a small amount, thereby contributing to the reduction of the manufacturing cost of the nanocomposite material.

Although the present invention has been described in detail only with respect to the embodiments described, it will be apparent to those skilled in the art that various modifications and variations are possible within the technical spirit of the present invention, and such modifications and variations belong to the appended claims. .

Claims (10)

With respect to 100 parts by weight of epoxy matrix resin, 0.1 to 2.5 parts by weight of vapor-grown carbon nanofibers as a reinforcing agent was physically mixed and dispersed, and then a curing agent was added to the dispersed mixture and cured. one step curing at 70-100 ° C. for 20-30 minutes / min; Two-step curing at 140-160 ° C. for 90-120 minutes; And three-step curing at 180 to 200 ° C. for 40 to 60 minutes. 6. A method of preparing an epoxy nanocomposite containing carbon-grown carbon nanofibers, comprising: The vapor-grown carbon nanofiber of claim 1, wherein the average diameter of the vapor-grown carbon nanofiber is 80-220 nm, the length is 5-25 µm, and the tensile strength is 0.1-3.5 GPa. Method for producing an epoxy nanocomposite containing. delete Epoxy nanocomposite material, characterized in that produced by the method for producing an epoxy nanocomposite containing the vapor-grown carbon nanofiber of claim 1. The epoxy nanocomposite according to claim 4, wherein the epoxy nanocomposite has a glass transition temperature of 110 to 160 ° C. The epoxy nanocomposite according to claim 4, wherein the coefficient of thermal expansion of the epoxy nanocomposite is 60 to 80 µm / m ° C before the glass transition temperature and 180 to 215 µm / m ° C after the glass transition temperature. The epoxy nanocomposite material according to claim 4, wherein the epoxy nanocomposite has an impact strength of 50 to 130 kgf · cm / cm and an interlaminar fracture toughness of ² to 10 MPa · m ^1/2 . The epoxy nanocomposite according to claim 4, wherein the epoxy nanocomposite has a frictional force of 0.3 to 1.1 N at room temperature and in a non-lubricated state. The epoxy nanocomposite according to claim 4, wherein the epoxy nanocomposite has a friction coefficient of 0.05 to 0.30 µ at room temperature and in a non-lubricated state. The epoxy nanocomposite according to claim 4, wherein the epoxy nanocomposite has a wear loss of 0.1 to 0.3 mm at room temperature and without lubrication.

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