KR102517512B1 - Flame retardant polyacrylonitrile composite material and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a flame retardant polyacrylonitrile composite material and a manufacturing method thereof, and more particularly, to a carbon material in which sulfur is doped in a copolymer resin having a polyacrylonitrile repeating unit and a repeating unit including a catechol group. It relates to a composite material in which the stabilization temperature is lowered and the flame retardancy is improved by adding the same, and a manufacturing method thereof.

Description

Flame retardant polyacrylonitrile composite and manufacturing method thereof

The present invention relates to a flame retardant polyacrylonitrile composite material and a manufacturing method thereof, and more particularly, to a carbon material in which sulfur is doped in a copolymer resin having a polyacrylonitrile repeating unit and a repeating unit including a catechol group. It relates to a composite material in which the stabilization temperature is lowered and the flame retardancy is improved by adding the same, and a manufacturing method thereof.

Polyacrylonitrile (PAN) is a typical precursor polymer for carbon fiber production. In the process of manufacturing carbon fiber, polyacrylonitrile goes through stabilization, carbonization, and graphitization processes. During the stabilization process, polyacrylonitrile exhibits flame retardancy that is not easily melted at high temperatures due to intramolecular or intermolecular crosslinking. However, in order to realize the flame retardancy of polyacrylonitrile, heat treatment of 300 ° C or higher is essential, and low stabilization efficiency and increase in electricity consumption due to long-term high-temperature heat treatment are pointed out as disadvantages of the material.

In order to lower the stabilization process temperature and improve efficiency, introduction of various co-monomers has been attempted when polyacrylonitrile is polymerized. In addition, research into introducing a halogen element to improve the flame retardancy of polyacrylonitrile is also being conducted.

Korean Patent Registration No. 10-1093140 Korean Patent Registration No. 10-1329796

An object of the present invention is to provide a polyacrylonitrile composite material capable of high efficiency stabilization at a low temperature.

An object of the present invention is to improve the flame retardancy of polyacrylonitrile composites.

The object of the present invention is not limited to the object mentioned above. The objects of the present invention will become more apparent from the following description, and will be realized by means and combinations thereof set forth in the claims.

A composite material according to an embodiment of the present invention includes a copolymer resin including a first repeating unit including a polyacrylonitrile and a second repeating unit including a catechol group; and a filler dispersed in the copolymer resin, wherein the filler may include a sulfur-doped carbon material.

The copolymer resin may be a block copolymer, a random copolymer or an alternating copolymer.

,

,

및 이들의 조합으로 이루어진 군으로부터 선택된 적어도 어느 하나를 포함할 수 있다.The second repeating unit,

,

,

And it may include at least one selected from the group consisting of combinations thereof.

The copolymer resin may be represented by Formula 1 below.

[Formula 1]

,

,

및 이들의 조합으로 이루어진 군으로부터 선택된 적어도 어느 하나를 포함하고, x는 9000 내지 9990의 정수이고, y는 10 내지 1000의 정수이다.In Formula 1, A is

,

,

and at least one selected from the group consisting of combinations thereof, x is an integer from 9000 to 9990, and y is an integer from 10 to 1000.

The copolymer resin may have a weight average molecular weight of 10,000 g/mol to 500,000 g/mol.

The molecular weight distribution of the copolymer resin may be 1.2 to 4.

The copolymer resin may have a maximum exothermic peak temperature of 200 °C to 300 °C measured according to a thermal stability evaluation method using differential scanning calorimetry (DSC).

The carbon material may include at least one selected from the group consisting of graphene oxide, reduced graphene oxide, carbon nanotubes, carbon fibers, and combinations thereof.

The filler may include 0.5% to 5% by weight of sulfur.

The composite material may include the filler in an amount of 0.1% to 20% by weight.

Heat release capacity per unit mass of the composite material may be 63 W/g or less.

The limiting oxygen index of the composite may be 38% or more.

The composite may have a density of 1.34 g/cm ³ or greater.

A method for manufacturing a composite material according to an embodiment of the present invention includes preparing a filler including a carbon material doped with sulfur; preparing a copolymer resin by polymerizing a precursor of the first repeating unit and a precursor of the second repeating unit; and mixing the filler and the copolymer resin.

Preparing the filler may include preparing a mixture including carbon material and sulfur; heat-treating the mixture to convert sulfur into molten sulfur and reacting the mixture; and removing sulfur from the reaction product.

The precursor of the first repeating unit may include acrylonitrile, and the precursor of the second repeating unit may include at least one selected from the group consisting of dihydroxy styrene, caffeic acid, dopamine methacrylamide, and combinations thereof. there is.

The composite material may be obtained by preparing a dispersion of the filler and mixing a copolymer resin with the dispersion.

According to the present invention, a polyacrylonitrile composite material having a low stabilization temperature can be obtained by introducing a repeating unit containing a catechol group. As a result, since high efficiency stabilization can be achieved at low temperature, the economics of the process can be greatly improved.

According to the present invention, a polyacrylonitrile composite having improved flame retardancy can be obtained by adding a sulfur-doped carbon material.

The effects of the present invention are not limited to the effects mentioned above. It should be understood that the effects of the present invention include all effects that can be inferred from the following description.

1 is a differential scanning calorimetry (DSC) result of the copolymer resin of Preparation Example 2-C.
2 is a temperature-heat release rate graph for Comparative Example 1 and Examples 1 to 2.
3 is a temperature-heat release rate graph for Comparative Example 2 and Examples 3 to 4.
4 is a temperature-heat release rate graph for Comparative Example 3 and Examples 5 to 6.

The above objects, other objects, features and advantages of the present invention will be easily understood through the following preferred embodiments in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosed content will be thorough and complete and the spirit of the present invention will be sufficiently conveyed to those skilled in the art.

Like reference numerals have been used for like elements throughout the description of each figure. In the accompanying drawings, the dimensions of the structures are shown enlarged than actual for clarity of the present invention. Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. These terms are only used for the purpose of distinguishing one component from another. For example, a first element may be termed a second element, and similarly, a second element may be termed a first element, without departing from the scope of the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise.

In this specification, terms such as "include" or "have" are intended to designate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, but one or more other features It should be understood that it does not preclude the possibility of the presence or addition of numbers, steps, operations, components, parts, or combinations thereof. In addition, when a part such as a layer, film, region, plate, etc. is said to be "on" another part, this includes not only the case where it is "directly on" the other part, but also the case where another part is present in the middle. Conversely, when a part such as a layer, film, region, plate, etc. is said to be "under" another part, this includes not only the case where it is "directly below" the other part, but also the case where another part is in the middle.

Unless otherwise specified, all numbers, values and/or expressions expressing quantities of components, reaction conditions, polymer compositions and formulations used herein refer to the number of factors that such numbers arise, among other things, to obtain such values. Since these are approximations that reflect the various uncertainties of the measurement, they should be understood to be qualified by the term "about" in all cases. Also, when numerical ranges are disclosed herein, such ranges are contiguous and include all values from the minimum value of such range to the maximum value inclusive, unless otherwise indicated. Furthermore, where such ranges refer to integers, all integers from the minimum value to the maximum value inclusive are included unless otherwise indicated.

The composite material according to the present invention is a copolymer resin including polyacrylonitrile (PAN); and a filler dispersed in the copolymer resin.

The copolymer resin is a kind of substrate forming the shape of the composite material.

The polyacrylonitrile is used as a precursor for producing high-performance carbon fibers. The stabilization process of polyacrylonitrile for the production of carbon fibers has a great influence on the physical properties of carbon fibers. Therefore, the present invention is characterized in that a comonomer containing a catechol group is used together in the process of polymerizing polyacrylonitrile to lower the stabilization process temperature and increase efficiency.

Specifically, the copolymer resin may include a first repeating unit including polyacrylonitrile and a second repeating unit including a catechol group. In addition, the copolymer resin may be a block copolymer, a random copolymer or an alternating copolymer.

,

,

및 이들의 조합으로 이루어진 군으로부터 선택된 적어도 어느 하나를 포함할 수 있다. The second repeating unit may be derived from a comonomer having a catechol group. Preferably, the second repeating unit is

,

,

And it may include at least one selected from the group consisting of combinations thereof.

The copolymer resin may include a polymer represented by Chemical Formula 1 below.

[Formula 1]

,

,

및 이들의 조합으로 이루어진 군으로부터 선택된 적어도 어느 하나를 포함하고, x는 9000 내지 9990의 정수이고, y는 10 내지 1000의 정수이다.In Formula 1, A is

,

,

and at least one selected from the group consisting of combinations thereof, x is an integer from 9000 to 9990, and y is an integer from 10 to 1000.

The copolymer resin can be obtained by radical polymerization of acrylonitrile (AN) and a comonomer (B) containing a catechol group in the presence of an initiator, as shown in Scheme 1 below. The initiator is not particularly limited, and may include 2,2'-azo-bis-isobutyrylnitrile (AIBN), benzoyl peroxide, and the like.

[Scheme 1]

B of Scheme 1 may include at least one selected from the group consisting of dihydroxy styrene, caffeic acid, dopamine methacrylamide, and combinations thereof.

However, the method for preparing the copolymer resin is not limited thereto, and any method may be adopted as long as it is widely used in the technical field to which the present invention belongs.

The copolymer resin may have a weight average molecular weight of 10,000 g/mol to 500,000 g/mol. If the weight average molecular weight of the copolymer resin is less than 10,000 g / mol, there may be a problem of reducing stabilization efficiency, and if it exceeds 500,000 g / mol, there may be a problem of reducing moldability due to a decrease in solubility.

The molecular weight distribution of the copolymer resin may be 1.2 to 4. If the molecular weight distribution of the copolymer resin is less than 1.2, there may be a problem of molecular weight reduction, and if it exceeds 4, there may be a problem of reducing production yield and performance uniformity.

The filler is a component for improving flame retardancy and thermal stability of the composite material, and may include a sulfur-doped carbon material.

The carbon material may include at least one selected from the group consisting of graphene oxide, reduced graphene oxide, carbon nanotubes, carbon fibers, and combinations thereof, and reduced graphene oxide may be preferred. Therefore, the filler may preferably include sulfur-doped reduced graphene oxide.

The filler may include 0.5% to 5% by weight of sulfur. If the sulfur content is less than 0.5% by weight, it is difficult to react by stirring the sulfur and the carbon material, and the effect of improving physical properties such as flame retardancy according to the addition of the filler may be insignificant. On the other hand, if the sulfur content exceeds 5% by weight, it may be difficult to remove sulfur remaining after preparing the filler.

The composite material may include the filler in an amount of 0.1% to 20% by weight. If the content of the filler is less than 0.1% by weight, the degree of improvement in thermal stability and flame retardancy of the composite material may be insignificant. On the other hand, if the content of the filler exceeds 20% by weight, dispersibility of the filler in the copolymer resin may be too low.

The manufacturing method of the composite material according to the present invention comprises the steps of preparing a filler containing a sulfur-doped carbon material; preparing a copolymer resin by polymerizing a precursor of the first repeating unit and a precursor of the second repeating unit; and mixing the filler and the copolymer resin.

Preparing the filler may include preparing a mixture including the carbon material and sulfur; heat-treating the mixture to convert sulfur into molten sulfur and reacting the mixture; and removing sulfur from the reaction product.

The mixture including the carbon material and sulfur may be heat treated at 100 °C to 300 °C, or 120 °C to 250 °C, or 150 °C to 180 °C, or 180 °C. The heat treatment time varies depending on the temperature, but may be, for example, 30 minutes to 6 hours or 3 hours to 4 hours.

When the mixture is heat-treated from 150° C. to 180° C., for example, up to 170° C., a viscous molten phase is formed. The molten phase includes molten sulfur. A sulfur-doped carbon material can be obtained through a reaction between molten sulfur and a carbon material. The sulfur may be introduced into a specific functional group such as a ketone group, an epoxy group, a phenol group, etc. present on the carbon material. In this case, when the carbon material is graphene oxide, since the sulfur may serve as a reducing agent, reduced graphene oxide doped with sulfur may be obtained.

Obtaining a sulfur solution by adding a sulfur soluble solvent to the sulfur remaining after the reaction is completed; and removing sulfur from the sulfur solution.

The sulfur-soluble solvent refers to a solvent having solubility characteristics for sulfur, and non-limiting examples include tetrahydrofuran, methylene chloride, dimethyldisulfide, sulfolane, chloroform, toluene, xylene, acetonitrile, dichloromethane, N-methyl Pyrrolidone, ethyl acetate, dimethyl ether, trichlorethylene, polyethylene glycol, isopropyl ketone, acetonitrile, dichloroethane, dimethylacetamide, dimethylformamide, cumene, benzene, p-chlorotoluene, 1,3 -mesitylene, styrene, chlorobenzene, alphamethylstyrene, ethylbenzene, diethanolamine, ethylamine, diethylamine, methylamine, ethylenediamine, diethylenetriamine, propylamine, ethanolamine, isopropylamine, triethylene tetraamine, chloroaniline, triethylamine, triethanolamine, dimethoxyethane, dimethoxymethane, dioxane and the like.

Ultrasonic treatment is performed on the sulfur solution, and the resulting product is filtered and/or washed to remove unreacted sulfur or sulfur physically attached to the carbon material.

Since the step of preparing the copolymer resin has been specifically described above, it will be omitted below.

A composite material may be prepared by adding the filler prepared as above to a solvent such as dimethyl sulfoxide (DMSO) to prepare a dispersion of the filler, and adding the copolymer resin thereto and stirring.

Hereinafter, the present invention will be described in more detail through examples. These examples are only for illustrating the present invention, and it will be apparent to those skilled in the art that the scope of the present invention is not to be construed as being limited by these examples.

Preparation Example 1 : Hwangi doped reduced of graphene oxide manufacturing

1 g of graphene oxide and 3 g of sulfur powder were mixed well using a mortar and pestle, and then put into a 500 ml round bottom flask.

Thereafter, the temperature of the oil bath is set to 180° C. and magnetic stirring is performed. It was confirmed that stirring began as sulfur began to melt at around 120 ° C. The temperature of the reaction mixture was heated to 170° C. to obtain molten sulfur, and the reaction mixture containing the same was stirred for 4 hours, and then the reaction was terminated.

After cooling the reaction product to room temperature, ultrasonication was performed using toluene to remove remaining sulfur. It was then filtered to obtain a toluene solution in which solid and sulfur were dissolved. The solid was washed with acetone and then dried in a vacuum oven at 180° C. for 24 hours to prepare reduced graphene oxide (hereinafter referred to as S-rGO) doped with 1.7 wt% sulfur.

Preparation Example 2 -A: copolymer resin A manufacturing

20 parts by weight of dihydroxy styrene (precursor of the second repeating unit) and acrylonitrile (precursor of the first repeating unit) in a molar ratio of 3:97 to 100 parts by weight of dimethyl sulfoxide (DMSO) under a nitrogen atmosphere was added and dissolved. After nitrogen was bubbled through the solution for 2 hours, radical polymerization was initiated at 70° C. and allowed to react for 24 hours. Next, the radical polymerization reaction was terminated by lowering the temperature to room temperature, and the reaction solution was poured into a solvent in which water and methanol were mixed in a volume ratio of 1:1 to precipitate and stirred for 3 hours to sufficiently remove the polymerization solvent. In addition, in order to remove the low molecular weight polymer and unreacted monomers, it was washed with methanol and acetone several times, and the precipitate was filtered, and sufficiently dried in a vacuum oven at 60 ° C for 12 hours or more to obtain a copolymer having a weight average molecular weight of 133,000 g / mol in solid form. Resin A was prepared. ¹ H-NMR results for the copolymer resin A are as follows.

¹ H NMR (600 MHz, DMSO- d ₆ ) δ 8.92-8.35 (d, 2H, hydroxyl group) 7.74-7.14 (m, 3H, aromatic group), 3.31-3.10 (br, 1H, alkyl group), 2.07-1.55 (br, 2H, alkyl group)

The copolymer resin A may be represented by Formula 2 below.

[Formula 2]

Preparation Example 2 -B: copolymer resin B manufacturing

Copolymer Resin B having a solid weight average molecular weight of 134,500 g/mol was prepared in the same manner as in Preparation Example 2-A, except that caffeic acid was used instead of dihydroxy styrene. ¹ H-NMR results for the copolymer resin B are as follows.

¹ H NMR (600 MHz, DMSO- d ₆ ) δ 13.27 (s, 1H, carboxylic acid group), 8.82-8.79 (d, 2H, hydroxyl group) 7.18-6.64 (m, 3H, aromatic), 3.15-3.11 (br, 1H, alkyl group), 2.14-2.01 (br, 2H, alkyl group)

The copolymer resin B may be represented by Formula 3 below.

[Formula 3]

Preparation Example 2 -C: copolymer resin C manufacturing

Copolymer Resin C having a solid weight average molecular weight of 134,500 g/mol was prepared in the same manner as in Preparation Example 1, except that dopamine methacrylamide was used instead of dihydroxy styrene. ¹ H-NMR results for the copolymer resin C are as follows.

¹ H NMR (600 MHz, DMSO- d ₆ ) δ 8.77-8.67 (d, 2H, hydroxyl group), 7.96-7.95 (br, 1H, amine group), 6.64-6.42 (m, 3H, aromatic group), 3.14 -2.88 (br, 1H, alkyl group), 2.11-1.44 (br, alkyl group), 1.31-1.11 (br, 3H, methyl group)

The copolymer resin C may be represented by Formula 4 below.

[Formula 4]

In order to evaluate the stabilization temperature of the copolymer resin C, differential scanning calorimetry (DSC) was performed. The film made of the copolymer resin C was placed in a convection oven and analyzed while raising the temperature from 50 °C to 300 °C at a rate of 10 °C per minute. The results are shown in FIG. 1 . As a control, the results for polyacrylonitrile (PAN) are also shown. Referring to this, it can be seen that the maximum exothermic peak temperature of the copolymer resin C measured according to the thermal stability evaluation method by differential scanning calorimetry (DSC) is 200°C to 300°C. Specifically, a first exothermic peak (T ₁ ) is measured between 200°C and 250°C, and a second exothermic peak (T ₂ ) is measured between 250°C and 275°C. It can be inferred that the cyclization reaction is initiated by the amide group from the second exothermic peak (T ₂ ), and that the cyclization reaction is initiated by the hydroxyl group from the first exothermic peak (T ₁ ). . In addition, since the copolymer resin C has a lower temperature than PAN at which a peak is found, the copolymer resin C undergoes a cyclization reaction at a lower temperature than PAN, that is, it is stabilized with high efficiency at a low temperature can know that This can be attributed to the second repeating unit including the catechol group included in the copolymer resin C.

Example 1 : Composite A manufacturing

0.0005 g of S-rGO was added to 10 ml of dimethyl sulfoxide (DMSO) and treated with ultrasonic waves at room temperature for 30 minutes to obtain an S-rGO dispersion. Subsequently, 0.5 g of copolymer resin A was added to the dispersion and stirred at 45° C. for 72 hours to obtain a viscous solution.

5 mL of the solution was cast on a glass substrate having a size of 3 cm X 4 cm, degassed in a vacuum oven set at room temperature for 4 hours, and then the solvent was removed at 75 ° C. for 24 hours to prepare a composite material A in the form of a film. In order to separate the composite material A from the glass substrate, the composite material A was immersed in water to separate the composite material A from the glass substrate, and the separated composite material A was sufficiently dried in a vacuum oven at 65° C. for 12 hours or more.

Example 2 : Composite A manufacturing

Composite A was prepared in the same manner as in Example 1, except that 0.005 g of S-rGO was used so that the content of the filler in the composite was 10% by weight.

Example 3 : Composite B manufacturing

A composite material was prepared in the same manner as in Example 1, except that copolymer resin B was used instead of copolymer resin A.

Example 4 : Composite B manufacturing

A composite material was prepared in the same manner as in Example 2, except that copolymer resin B was used instead of copolymer resin A.

Example 5 : Composite C manufacturing

A composite material was prepared in the same manner as in Example 1, except that copolymer resin C was used instead of copolymer resin A.

Example 6 : Composite C manufacturing

A composite material was prepared in the same manner as in Example 2, except that copolymer resin C was used instead of copolymer resin A.

Comparative Example 1

Without adding S-rGO, 0.5 g of copolymer resin A was added to 10 ml of dimethyl sulfoxide (DMSO) and stirred at 45° C. for 72 hours to obtain a viscous solution.

5 mL of the solution was cast on a glass substrate having a size of 3 cm X 4 cm, degassed for 4 hours in a vacuum oven set at room temperature, and then the solvent was removed at 75° C. for 24 hours to prepare a film. In order to separate the film from the glass substrate, the film was separated from the glass substrate by immersion in water, and the separated film was sufficiently dried in a vacuum oven at 65° C. for 12 hours or more.

Comparative Example 2

A film was prepared in the same manner as in Comparative Example 1, except that copolymer resin B was used instead of copolymer resin A.

Comparative Example 3

A film was prepared in the same manner as in Comparative Example 1, except that copolymer resin C was used instead of copolymer resin A.

Experimental example 1 : Manufacture of stabilized composites

Stabilization of the samples according to Examples 1 to 6 and Comparative Examples 1 to 3 was performed in a convection oven. Each sample was placed in a 20 ml glass vial and placed uncovered in a convection oven. After raising the temperature to 300 °C at a rate of 20 °C per minute, a stabilized sample was obtained by maintaining the temperature at 300 °C for 5 minutes.

Evaluation example 1 : Flame retardancy analysis

Temperature-heat release rate (HRR) graphs of each sample according to Examples 1 to 6 and Comparative Examples 1 to 3 are shown in FIGS. 2 to 4 . Figure 2 is the results of Example 1, Example 2 and Comparative Example 1 including copolymer resin A, Figure 3 is the result of Example 3, Example 4 and Comparative Example 2 including copolymer resin B 4 is a result of Example 5, Example 6 and Comparative Example 3 including the copolymer resin C.

In addition, the heat release capacity (HRC), peak heat release rate (PHRR), char yield, limiting oxygen index (LOI) and density for each sample are shown in Table 1. to Table 3.

The flame retardancy analysis was performed using a microcalorimeter (MCC), and the temperature was raised to 850 ° C at a temperature increase rate of 1 ° C per second. yield) was calculated. In addition, the density is a value measured 6 hours after the sample was put into the density gradient pipe (1.2-1.6) after stabilization. The flame retardancy and density of polyacrylonitrile-based materials show a close relationship, and the flame retardancy of polyacrylonitrile-based materials can be easily predicted through the density measured after stabilization. For example, conventional polyacrylonitrile-based flame retardant materials show a density of around 1.4 after going through a stabilization process, which is confirmed to show excellent flame retardancy of 38% or more in the LOI value, which is a representative measure for flame retardancy evaluation. The LOI was calculated through Equation 1, which is the most widely used.

[Equation 1]

(In Equation 1, the char yield is the weight ratio of the residual amount after burning up to 850 ° C. compared to the initial weight)

division Filler dosage (% by weight) HRC
(W/g) PHRR
(W/g) Char yield (%) LOI
(%) density
(g/cm ³ ) Example 1 One 63 63.9 60.3 41.5 1.37 Example 2 10 40 38.0 65.8 43.7 1.38 Comparative Example 1 0 77 76.5 47.5 36.5 1.33

division Filler dosage (% by weight) HRC
(W/g) PHRR
(W/g) Char yield (%) LOI
(%) density
(g/cm ³ ) Example 3 One 57 45.3 60.3 41.5 1.36 Example 4 10 27 31.3 66.7 44.1 1.38 Comparative Example 2 0 67 56.4 48.6 36.9 1.33

division Filler dosage (% by weight) HRC
(W/g) PHRR
(W/g) Char yield (%) LOI
(%) density
(g/cm ³ ) Example 5 One 40 40.0 63.6 42.9 1.37 Example 6 10 30 30.1 69.6 45.2 1.39 Comparative Example 3 0 58 50.1 49.8 37.3 1.34

Referring to Tables 1 to 3, it can be seen that, compared to Comparative Examples 1 to 3, in Examples 1 to 6, the amount of heat released and the maximum heat release rate decreased as the content of the filler increased. Specifically, the composite material according to the present invention has a heat dissipation rate per unit mass (HRC) of 63 W/g or less, preferably 27 W/g. This means that heat dissipation during the combustion process is reduced, and it can be seen that excellent flame retardant properties are obtained.

In addition, the composite material according to the present invention had a density of 1.34 g/cm ³ or more, and the highest reached 1.39 g/cm ³ , and the chair yield measured after burning up to 850 ° C was also in Comparative Examples 1 to 3. The LOI value confirmed through this increased by more than 38% and up to 45.2%.

The embodiments of the present invention described above should not be construed as limiting the technical spirit of the present invention. The protection scope of the present invention is limited only by the matters described in the claims, and those skilled in the art can improve and change the technical idea of the present invention in various forms. Therefore, these improvements and modifications will fall within the protection scope of the present invention as long as they are obvious to those skilled in the art.

Claims (19)

preparing a filler including a carbon material doped with sulfur;
preparing a copolymer resin by polymerizing a starting material including a precursor of the first repeating unit and a precursor of the second repeating unit; and
Including; obtaining a composite material by mixing the filler and the copolymer resin,
The composite material may include the copolymer resin; and the filler dispersed in the copolymer resin;
The first repeating unit includes polyacrylonitrile, and the second repeating unit includes a catechol group,
The step of preparing the filler is
preparing a mixture containing carbon ash and sulfur powder;
heat-treating the mixture at 100° C. to 300° C. to convert the sulfur powder into molten sulfur and reacting the mixture; and
A method for producing a composite material comprising the steps of removing sulfur from the reaction product. delete According to claim 1,
The copolymer resin is a block copolymer, random copolymer or alternating copolymer (Alternating copolymer) method of producing a composite material. According to claim 1,
The second repeating unit,

,

,

And a method for producing a composite material comprising at least one selected from the group consisting of combinations thereof. According to claim 1,
The copolymer resin is a method for producing a composite material represented by the following formula (1).
[Formula 1]

In Formula 1, A is

,

,

And includes at least one selected from the group consisting of combinations thereof, x is an integer from 9000 to 9990, y is an integer from 10 to 1000. According to claim 1,
The weight average molecular weight of the copolymer resin is a method for producing a composite material of 10,000 g / mol to 500,000 g / mol. According to claim 1,
The molecular weight distribution of the copolymer resin is a method for producing a composite material of 1.2 to 4. According to claim 1,
The copolymer resin is a method for producing a composite material having a maximum exothermic peak temperature of 200 ° C. to 300 ° C. measured according to a thermal stability evaluation method by differential scanning calorimetry (DSC). According to claim 1,
The carbon material is a method for producing a composite material comprising at least one selected from the group consisting of graphene oxide, reduced graphene oxide, carbon nanotubes, carbon fibers, and combinations thereof. According to claim 1,
The filler is a method for producing a composite material containing 0.5% to 5% by weight of sulfur. According to claim 1,
The composite material manufacturing method of the composite material containing the filler in 0.1% to 20% by weight. According to claim 1,
Method for producing a composite material having a heat release capacity per unit mass of the composite material of 63 W / g or less. According to claim 1,
Method for producing a composite material having a limiting oxygen index of the composite material of 38% or more. According to claim 1,
The density of the composite is 1.34 g / cm ³ Method for producing a composite material or more. delete delete According to claim 1,
A method for producing a composite material in which the precursor of the first repeating unit includes acrylonitrile. According to claim 1,
A method for producing a composite material, wherein the precursor of the second repeating unit includes at least one selected from the group consisting of dihydroxy styrene, caffeic acid, dopamine methacrylamide, and combinations thereof. According to claim 1,
A method for producing a composite material comprising preparing a dispersion of the filler and mixing a copolymer resin with the dispersion.

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