KR20230025160A - Polymer-fiber composite particle manufacturing method, polymer-fiber composite film and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a method for manufacturing polymer-fiber composite particles, a polymer-fiber composite film and a manufacturing method thereof, and more particularly, to a method for manufacturing polymer-fiber composite particles having excellent mechanical strength, being environmentally friendly and having improved dispersibility, a polymer-fiber composite film and a manufacturing method thereof. The method for manufacturing the polymer-fiber composite particles comprises the steps of: adding polymer fine particles and an organic solvent to an aqueous solution in which cellulose nanofibers are dispersed; stirring the aqueous solution to form a Pickering emulsion; and obtaining the polymer-fiber composite particles from the aqueous solution.

Description

Polymer-fiber composite particle manufacturing method, polymer-fiber composite film and manufacturing method thereof

The present invention relates to a method for producing polymer-fiber composite particles, a polymer-fiber composite film, and a method for manufacturing the same, and more particularly, to a method for manufacturing polymer-fiber composite particles having excellent mechanical strength, being environmentally friendly and having improved dispersibility, It relates to a polymer-fiber composite film and a manufacturing method thereof.

Cellulose is Earth's most abundant natural polymer produced by plants, bacteria and algae. Nanocellulose made from such cellulose is a crystalline polymer with a high degree of crystallinity, and also has a high tensile strength (2-6 GPa) and elastic modulus (130-150 GPa). Although the mechanical properties of these nanocelluloses are higher than those of metals such as cast iron or stainless steel, the specific gravity is 1.6, which is very light compared to the specific gravity of 7.8 steel.

In addition, unlike glass fiber or carbon fiber, cellulose is a biodegradable natural polymer. Due to its light, hard and eco-friendly characteristics, cellulose is attracting attention as a filler for various polymer compounds such as polypropylene and polystyrene, which have low tensile and compressive strength. .

However, glucose, a monomer of cellulose, contains hydroxyl groups such as hydroxyl group (-OH) and carboxy group (-COOH) and thus has a polar interface, whereas synthetic high molecular compounds such as polypropylene and polystyrene have non-polar interface properties. Due to the difference in interfacial properties, the adsorption force between the two materials is low, so that the cellulose is not well dispersed in the polymer matrix, and there is a problem that aggregation or phase separation may occur.

In order to overcome these problems, methods of functionalizing cellulose molecules such as cationization, esterification, and acetylation by adding various surfactants are known, but these methods require complicated processes, and sometimes excellent mechanical properties of cellulose are known. can lower

Therefore, there is a demand for the development of a new method for manufacturing polymer-fiber composite particles that has a simpler manufacturing process, excellent mechanical strength, is environmentally friendly, and has improved dispersibility of cellulose in a polymer matrix.

The present invention is to provide a method for producing polymer-fiber composite particles having excellent mechanical strength, being environmentally friendly, and having improved dispersibility.

In addition, the present invention is to provide a polymer-fiber composite film comprising the composite particles produced by the above manufacturing method.

In addition, the present invention is to provide a method for manufacturing a polymer-fiber composite film using the composite particles prepared by the above manufacturing method.

In the present specification, adding polymer fine particles and an organic solvent to an aqueous solution in which cellulose nanofibers are dispersed; stirring the aqueous solution to form a Pickering emulsion; and obtaining polymer-fiber composite particles from the aqueous solution;

The organic solvent is benzene, chlorobenzene, 1,2-dichlorobenzene, o-xylene, m-xylene, p - Provided is a method for producing polymer-fiber composite particles comprising at least one selected from the group consisting of p-xylene and toluene.

In the present specification, a polymer-fiber composite film comprising the composite particles prepared by the above manufacturing method is also provided.

In the present specification, there is also provided a method for manufacturing a polymer-fiber composite film, including the step of thermally compressing the composite particles prepared by the above manufacturing method.

Hereinafter, a method for manufacturing a polymer-fiber composite particle, a polymer-fiber composite film, and a manufacturing method thereof according to specific embodiments of the present invention will be described in more detail.

Terms used in this specification are only used to describe exemplary embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as "comprise", "comprise" or "having" are intended to indicate that there is an embodied feature, number, step, component, or combination thereof, but one or more other features or It should be understood that the presence or addition of numbers, steps, components, or combinations thereof is not precluded.

Since the present invention can have various changes and various forms, specific embodiments will be exemplified and described in detail below. However, this is not intended to limit the present invention to a particular disclosed form, and it should be understood to include all modifications, equivalents, and substitutes included in the spirit and technical scope.

According to one embodiment of the invention, adding polymer fine particles and an organic solvent to the aqueous solution in which the cellulose nanofibers are dispersed; stirring the aqueous solution to form a Pickering emulsion; and obtaining polymer-fiber composite particles from the aqueous solution, wherein the organic solvent is benzene, chlorobenzene, or 1,2-dichlorobenzene. , Polymer-fiber containing at least one selected from the group consisting of o-xylene, m-xylene, p-xylene and toluene A method for producing multiparticulates may be provided.

The inventors of the present invention, polymer-fiber composite particles proceeding with research on the method, adding a polymer fine particle and an organic solvent to the aqueous solution in which the cellulose nanofibers are dispersed; stirring the aqueous solution to form a Pickering emulsion; and obtaining polymer-fiber composite particles from the aqueous solution; and, when the organic solvent includes at least one selected from a predetermined group, uniformly adsorbing cellulose nanofibers to a polymer interface to obtain a polymer matrix. It was confirmed through experiments that polymer-fiber composite particles with improved dispersibility of cellulose nanofibers could be prepared, and the invention was completed.

The method for producing the polymer-fiber composite particles of the embodiment does not include additives such as surfactants and stabilizers, and is eco-friendly and simple because it is prepared by swelling the polymer fine particles with a small amount of organic solvent and then forming a Pickering emulsion. may have a manufacturing process.

First, the method for preparing the polymer-fiber composite particles of the embodiment may include adding polymer fine particles and an organic solvent to an aqueous solution in which cellulose nanofibers are dispersed.

Nanocellulose, which can be obtained by nanonizing cellulose, can be largely divided into cellulose nanofibril (CNF) and cellulose nanocrystal (CNC) according to the extraction method from biomass.

Cellulose nano fiber (CNF) is an ultra-fine fiber made by unraveling plant fiber at the nano (one-billionth) level. can

These cellulose nanofibers are composed of nano-sized cellulose fibrils with a high aspect ratio, the fibril width is 5 to 20 nm, the length is generally several micrometers, and thixotropy is exhibited.

On the other hand, the average length of the cellulose nanofibers may be 250 nm to 1200 nm, the average thickness may be 11 nm to 15 nm.

1 a) shows a picture and a TEM picture of an aqueous solution in which cellulose nanofibers are dispersed, and b) shows the average length and average thickness of cellulose nanofibers.

At this time, the cellulose nanofibers can use non-functionalized cellulose nanofibers that do not functionalize the cellulose interface through surfactants, and there is no need to design a complicated process of reacting cellulose and surfactants, and The problem of deterioration of cellulose can be avoided.

On the other hand, the concentration of cellulose nanofibers in the aqueous solution is 0.1 g / L or more, 0.3 g / L or more, 0.5 g / L or more, 0.7 g / L or more, 10 g / L or less, 7 g / L or less, 5 g /L, may be included below 3 g/L. Within this range, it is possible to provide a polymer-fiber composite particle having excellent dispersibility in a polymer matrix.

Meanwhile, a water-soluble salt such as NaCl or KCl or an acid such as HCl may be additionally added to the aqueous solution along with cellulose nanofibers. The water-soluble salt or acid serves to facilitate dispersion by lowering the electrostatic repulsive force between cellulose nanofibers in an aqueous solution.

On the other hand, the organic solvent is a solvent with good wettability for the polymer, and the polymer fine particles in the aqueous solution are swelled by the organic solvent, and the energy of the polymer interface is lowered, resulting in the formation of cellulose nanofibers on the polymer surface. adsorption is facilitated.

As the organic solvent, a solvent capable of swelling the polymer fine particles and at the same time adsorbing the cellulose nanofibers may be used.

For example, benzene, chlorobenzene, 1,2-dichlorobenzene, o-xylene, m-xylene, p- It may be at least one selected from the group consisting of p-xylene and toluene.

Meanwhile, the organic solvent may be added in an amount of 1 μl to 100 μl based on 1 ml of the aqueous solution in which the cellulose nanofibers are dispersed. Within this range, the energy of the polymer interface can be lowered by wetting the interface of the polymer fine particles in the aqueous solution and then swelling.

That is, the polymer microparticles can be swollen using a small amount of organic solvent, and through this, the bonding force between the polymer microparticles and the cellulose nanofibers can be improved.

On the other hand, using polypropylene as polymer fine particles, swelling of polypropylene and adsorption of cellulose nanofibers according to various organic solvents were confirmed.

2 (a) shows general polypropylene particles in which cellulose nanofibers are not dispersed, and (b) to (h) use the method for producing polymer-fiber composite particles of the present application, but (b) do not add an organic solvent (c) chlorobenzene, (d) methyl acrylate, (e) methyl methacrylate, (f) hexadecane, (g) This is a photograph of the polymer-fiber composite particles prepared by adding 1,2-dichlorobenzene and (h) p-xylene with a scanning electron microscope (SEM).

In (c), (g) and (h) of FIG. 2, the surface is irregular, and thread-like cellulose nanofibers are observed on the surface (red arrow). Accordingly, the method of manufacturing the polymer-fiber composite particle of the present application However, when chlorobenzene, 1,2-dichlorobenzene or p-xylene is added as an organic solvent, polymer fine particles are swollen to form cellulose on the polymer surface. It can be confirmed that the nanofibers are evenly adsorbed. However, the organic solvent is not limited to chlorobenzene, 1,2-dichlorobenzene and p-xylene, and as described above, various solvents capable of swelling the polymer fine particles and adsorbing cellulose nanofibers at the same time can be used.

On the other hand, the example of the polymer fine particles is not limited, and any polymer capable of swelling by the organic solvent and forming a Pickering emulsion to be described later through interaction with cellulose nanofibers can be used without limitation. .

Examples include polypropylene (PP), polypropylene surface-modified with maleic anhydride (MAPP), polyethylene (PE), polystyrene (PS), polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), and polylactic acid. (PLA), acrylonitrile butadiene latex (Acrylonitrile butadiene latex), styrene butadiene latex (Styrene butadiene latex) such as rubber (rubber) and polyurethane elastomer (elastomer), and the like can be used.

On the other hand, it was confirmed that polymer-fiber composite particles in which cellulose nanofibers were evenly dispersed in various polymer fine particles were generated using chlorobenzene as an organic solvent.

3 is a polymer-fiber composite particle manufacturing method of the present application, but prepared by adding chlorobenzene as an organic solvent and (a) polymethyl methacrylate (PMMA) and (b) polystyrene (PS) as polymer fine particles. This is a photograph of the polymer-fiber composite particles observed with a scanning electron microscope (SEM).

The red arrows in FIG. 3 indicate thread-shaped cellulose nanofibers, and according to FIG. 3, when using the method for manufacturing polymer-fiber composite particles of the present invention, polymers in which cellulose nanofibers are uniformly adsorbed at various polymer fine particle interfaces- It can be confirmed that the fiber composite particles can be prepared.

At this time, the polymer fine particles are 1 mg or more, 3 mg or more, 5 mg or more, 7 mg or more, 20 mg or less, 15 mg or less, 13 mg or less, 11 mg or less with respect to 1 ml of the aqueous solution in which the cellulose nanofibers are dispersed , can be added in an amount of 9 mg or less. Within this range, the energy of the polymer interface may be lowered due to swelling of the polymer interface due to the addition of the organic solvent.

Meanwhile, the particle size of the polymer fine particles may be 0.1 μm or more, 0.3 μm or more, 0.5 μm or more, or 0.7 μm or more, and 300 μm or less, 200 μm or less, or 100 μm or less. Within this range, the cellulose nanofibers can be evenly dispersed and adsorbed in the polymer matrix.

The method for preparing the polymer-fiber composite particles of the embodiment may include forming a Pickering emulsion by stirring the aqueous solution.

An emulsion is a system in which oil droplets are dispersed in water or droplets are dispersed in oil. In particular, a high internal phase emulsion (HIPE) is a system in which the volume of the dispersed droplets is 74% or more by volume of the total emulsion. refers to an emulsion system. This highly dispersed phase emulsion has a very high specific surface area to volume compared to normal emulsions, so it can be usefully used, and it is possible to manufacture various porous materials by using the highly dispersed phase emulsion as a template, so that filters, sensors, It can be used in all fields of industry, such as adsorbents and catalyst supports.

The emulsion according to the embodiment may be an oil-in-water type pickering emulsion in which the oil phase is a dispersed phase and the water phase is a continuous phase. there is. In this way, by having the oil phase as the dispersed phase, it is possible to obtain a very stable emulsion in which phase separation does not easily occur even after a long period of time. When the oil layer and the water layer are mixed to form an oil phase, which is a dispersed phase, and an aqueous phase, which is a continuous phase, the polymer monomers dispersed in the water phase cause a depletion pressure, so that the cellulose nanofibers are well formed on the surface (interface) of the oil droplets. This is because phase separation due to interfacial tension can be suppressed by lowering the interfacial tension by allowing adsorption.

In the Pickering emulsion formation method, since the size of the emulsion formed has a specific size in a thermodynamic equilibrium state, it is possible to form a small and uniform emulsion on the order of 100 nm.

According to the present invention, when dispersing cellulose nanofibers in a polymer matrix, the polymer is swelled with a small amount of solvent to lower the energy of the polymer interface to adsorb the cellulose nanofibers, and since water is used as a solvent for the emulsion, it is eco-friendly and the manufacturing process is simple. do. In addition, since the polymer-fiber composite particles are prepared using only physical treatment methods such as swelling and Pickering emulsion, the process is simple and easy to manufacture, and the reproducibility is excellent.

In addition, the polymer fine particles, cellulose nanofibers, and organic solvents, which are the main raw materials used in the above-described polymer-fiber composite particle manufacturing method, are inexpensive and easy-to-obtain raw materials that are economical and eco-friendly because the solvent of the emulsion is water. It has this simple advantage.

That is, according to the method for producing the polymer-fiber composite particle of the embodiment, after swelling the polymer from a small amount of solvent, the cellulose nanofibers are uniformly adsorbed on the polymer interface using Pickering emulsion, and finally the cellulose nanofibers are attached to the synthetic polymer matrix. Well-dispersed polymer-fiber composite particles can be prepared.

Meanwhile, the stirring may be performed using a physical stirrer (vortexing machine).

The method for preparing the polymer-fiber composite particles of the embodiment may include obtaining the polymer-fiber composite particles from the aqueous solution.

Specifically, after the formation of the Pickering emulsion, centrifugation, washing and drying of the resulting polymer-fiber composite particles may be included.

For example, the resulting polymer-fiber composite particles are washed with water and/or methanol to remove the solvent remaining in the composite particles, non-adsorbed cellulose nanofibers, and water-soluble salts such as NaCl, and then dried to obtain the final polymer - Fiber composite particles can be obtained.

According to another embodiment of the present invention, a polymer-fiber composite film including the composite particles prepared by the method for preparing the polymer-fiber composite particles may be provided.

Information regarding the method for preparing the polymer-fiber composite particle includes the information described above with respect to the embodiment.

The polymer-fiber composite film including the composite particles prepared by the method for preparing the polymer-fiber composite particles is transparent, has improved mechanical properties, and has excellent heat resistance.

For example, a polymer-fiber composite film containing polypropylene, which is a transparent polymer fine particle, may have transparency similar to that of general transparent polypropylene in which cellulose nanofibers are not dispersed in the polypropylene interface.

In addition, the polymer-fiber composite film may have improved mechanical properties while maintaining excellent heat resistance compared to pure polymer films.

For example, the Young's modulus of the composite film may be 0.60 GPa or more, 0.65 GPa or more, 0.70 GPa or more, 0.75 GPa or more, or 0.80 GPa or more.

In addition, the tensile strength (Tensile strength) of the composite film may be 19.0 MPa or more, 19.5 MPa or more, or 20.0 MPa or more.

That is, the composite film maintains the light and easy-to-process characteristics of a film containing polymer fine particles, and reinforces weak mechanical strength through cellulose nanofibers, such as automobile bumpers, aerospace materials, electronic products, building materials, etc. It can be applied to fields requiring light weight, heat resistance, impact resistance, and chemical resistance.

In addition, the composite film includes cellulose nanofibers, which are biodegradable natural polymers, and has excellent thermal decomposability and is suitable for recycling, thereby being environmentally friendly.

Meanwhile, according to another embodiment of the present invention, a method for producing a polymer-fiber composite film comprising the step of thermally compressing the composite particles prepared by the method for manufacturing the polymer-fiber composite particles may be provided.

Information regarding the method for preparing the polymer-fiber composite particle includes the information described above with respect to the embodiment.

The method of thermally compressing the composite particles prepared by the method for preparing the polymer-fiber composite particles may be performed at a temperature of 100 ° C. to 180 ° C. and a pressure of 10 MPa to 30 MPa. The fiber composite film has improved mechanical properties and excellent heat resistance while being transparent.

4 illustrates a polymer-fiber composite particle and a method for manufacturing a composite film including the same.

Specifically, (a) of FIG. 4 shows the addition of polypropylene (PP) or maleic anhydride surface-modified polypropylene (MAPP) as polymer fine particles to an aqueous solution in which cellulose nanofibers are dispersed, (b ) shows the step of forming a Pickering emulsion by stirring it after adding an organic solvent.

Figure 4 (c) shows the uniform adsorption of cellulose nanofibers (CNF) on the interface of the swollen polymer fine particles after about 8 hours, and (d) shows the final The formed polymer-fiber composite particles are shown, and (e) shows a step of preparing a polymer-fiber composite film by thermally compressing the resulting polymer-fiber composite particles.

On the other hand, (f) of FIG. 4 shows a state in which a Pickering emulsion is not formed by not stirring after adding an organic solvent, and (g) shows that swelling of the polymer fine particles does not occur, and cellulose is formed on the surface of the polymer. It shows that the nanofibers were not immobilized and were washed out during the washing process.

According to the present invention, it is possible to provide a method for producing polymer-fiber composite particles having excellent mechanical strength, being environmentally friendly, and having improved dispersibility.

In addition, it is possible to provide a polymer-fiber composite film comprising the composite particles manufactured by the above manufacturing method.

In addition, it is possible to provide a method for manufacturing a polymer-fiber composite film using the composite particles prepared by the above manufacturing method.

1 a) shows a picture and a TEM picture of an aqueous solution in which cellulose nanofibers are dispersed, and b) shows the average length and average thickness of cellulose nanofibers.
2 (a) shows general polypropylene particles in which cellulose nanofibers are not dispersed, and (b) to (h) use the method for producing polymer-fiber composite particles of the present application, but (b) do not add an organic solvent (c) chlorobenzene, (d) methyl acrylate, (e) methyl methacrylate, (f) hexadecane, (g) This is a photograph of the polymer-fiber composite particles prepared by adding 1,2-dichlorobenzene and (h) p-xylene with a scanning electron microscope (SEM).
3 is a polymer-fiber composite particle manufacturing method of the present application, but prepared by adding chlorobenzene as an organic solvent and (a) polymethyl methacrylate (PMMA) and (b) polystyrene (PS) as polymer fine particles. This is a photograph of the polymer-fiber composite particles observed with a scanning electron microscope (SEM).
4 illustrates a polymer-fiber composite particle and a method for manufacturing a composite film including the same.
Figure 5 is a photograph of the polymer-fiber composite particles produced according to Preparation Examples 1 to 3 observed with a scanning electron microscope (SEM).
6 is a photograph of the polymer-fiber composite particles produced according to Preparation Example 5 and Comparative Example 1 observed with a scanning electron microscope (SEM).
7 is a photograph of the transparency of the polymer-fiber composite films of Examples 1 to 3 and the polypropylene film of Comparative Example 2.
Figure 8 shows the stress-strain curves of the polymer-fiber composite films of Examples 1 to 4 and the polypropylene film of Comparative Example 2.
Figure 9 shows the thermal weight loss curves of the polymer-fiber composite films of Examples 1 to 3 and the polypropylene film of Comparative Example 2.

The invention is explained in more detail in the following examples. However, the following examples are merely illustrative of the present invention, and the contents of the present invention are not limited by the following examples.

Preparation Example 1

An aqueous solution in which cellulose nanofibers (diameter 13 nm, length 722 μm) was uniformly dispersed at a concentration of 1 g/L was prepared. NaCl was added to the aqueous solution at a molar concentration of 100 mM to facilitate dispersion by lowering the electrostatic repulsive force between the cellulose nanofibers in the aqueous solution.

After adding 25 mg of polypropylene particles having a particle size of 2.3 μm to 3 ml of the aqueous solution, 3.5 μl (15% v / v, solvent / PP) of chlorobenzene was added to the polypropylene particles of the aqueous solution using a micropipette. .

Thereafter, the mixture was stirred for 1 minute at 3,000 rpm using a vortexing machine.

After 8 hours, the resulting polymer-fiber composite particles were centrifuged, washed sequentially with water and methanol to remove NaCl, solvent and non-adsorbed cellulose nanofibers, and dried in a vacuum and at 25 °C for 12 hours to obtain polymer-fiber composites. Fiber composite particles were prepared.

Preparation Example 2

Polymer-fiber composite particles were prepared in the same manner as in Preparation Example 1, except that polypropylene particles having a particle size of 1.5 μm were used.

Preparation Example 3

Polymer-fiber composite particles were prepared in the same manner as in Preparation Example 1, except that polypropylene particles having a particle size of 0.7 μm were used.

Production Example 4

The same as in Preparation Example 1, except that polypropylene modified with maleic anhydride (MAPP; Sigma Aldrich, 427845) was used by adding 5% of maleic anhydride to 100% by weight of polypropylene particles having a particle size of 1.5 μm. In this way, polymer-fiber composite particles were prepared.

Preparation Example 5

Polymer-fiber composite particles were prepared in the same manner as in Preparation Example 1, except that NaCl was not added to the aqueous solution.

Comparative Example 1

An aqueous solution in which cellulose nanofibers (diameter 13 nm, length 722 μm) was uniformly dispersed at a concentration of 1 g/L was prepared. NaCl was added to the aqueous solution at a molar concentration of 100 mM.

After adding 25 mg of polypropylene particles having a particle size of 300 μm to 3 ml of the aqueous solution, the mixture was stirred for 1 minute at 3,000 rpm using a vortexing machine.

After 8 hours, the resulting composite particles were centrifuged, washed sequentially with water and methanol to remove NaCl, solvent and non-adsorbed cellulose nanofibers, and dried in vacuum and at 25 °C for 12 hours to obtain polymer-fiber composite particles. was manufactured.

Example 1

A polymer-fiber composite film was prepared by compressing the polymer-fiber composite particles prepared in Preparation Example 1 at 140 °C and 20 MPa for 1 minute.

Examples 2 to 4

A polymer-fiber composite film was prepared in the same manner as in Example 1, except that the polymer-fiber composite particles of Preparation Examples 2 to 4 were used instead of the polymer-fiber composite particles of Preparation Example 1.

Comparative Example 2

A polypropylene film was prepared by compressing normal polypropylene particles (PP; 0.7 μm) in which cellulose nanofibers were not dispersed at 140 °C and 20 MPa for 1 minute.

[Experimental example]

1. Confirmation of the creation of multiparticles

Figure 5 is a photograph of the polymer-fiber composite particles produced according to Preparation Examples 1 to 3 observed with a scanning electron microscope (SEM).

6 is a photograph of the polymer-fiber composite particles produced according to Preparation Example 5 and Comparative Example 1 observed with a scanning electron microscope (SEM).

The red arrows in FIGS. 5 and 6 represent thread-like cellulose nanofibers, and according to FIGS. 5 and 6, the polymer-fiber composite particles produced according to Preparation Examples 1 to 3 and 5 are cellulose without aggregation or phase separation on the polymer surface. It can be seen that the nanofibers are evenly dispersed.

2. Check the transparency of the composite film

7 is a photograph of the transparency of the polymer-fiber composite films of Examples 1 to 3 and the polypropylene film of Comparative Example 2.

It can be confirmed that the polymer-fiber composite film using the composite particles prepared by the manufacturing method of the present application has an equivalent level of transparency compared to a general polypropylene film in which cellulose nanofibers are not dispersed.

3. Physical property measurement

The polymer-fiber composite films of Examples 1 to 4 and the polypropylene film of Comparative Example 2 were measured for Young's modulus, tensile strength, and elongation at break, and the results are shown in Table 1 below. and shown in FIG. 8 .

A 200 N load cell (DBCM-20, BONGSHIN) and Oriental Motor's RKE543AC were used, and the specimen was made into a size of 0.2 X 3 X 30 mm (thickness x width x length) and the strain was measured at a rate of 0.1 min ^-1 .

Comparative Example 2 Example 2 Example 4 Young's modulus GPa) 0.56 ± 0.00 0.85 ± 0.02 0.82 ± 0.02 Tensile strength (MPa) 18.7±1.8 20.1 ± 0.1 23.8 ± 0.6 Elongation at break (%) >100% 5.9 ± 0.3 54.5 ± 31.8

According to Table 1, it was confirmed that the polymer-fiber composite film according to the present example had increased Young's modulus and tensile strength compared to the pure polypropylene film of Comparative Example 2.

Figure 8 shows the stress-strain curves of the polymer-fiber composite films of Examples 1 to 4 and the polypropylene film of Comparative Example 2.

According to FIG. 8 , it can be confirmed that the Young's modulus, which is the slope of the stress-strain curve, in the elastic deformation region of the polymer-fiber composite film according to the present embodiment increased.

4. Thermal Weight Loss Measurement

Thermal weight loss was measured for the polymer-fiber composite films prepared in Examples 1 to 3 and the polypropylene film of Comparative Example 2. TG209 F1 Libra (NETZSCH) was used as a thermogravimetric analyzer, and the results are shown in FIG. 9 .

Figure 9 shows the thermal weight loss curves of the polymer-fiber composite films of Examples 1 to 3 and the polypropylene film of Comparative Example 2.

According to FIG. 9, it was confirmed that the thermal decomposition temperature of the polymer-fiber composite film according to the present embodiment was the same as that of the pure polypropylene film.

That is, according to Table 1, FIGS. 8 and 9, it was confirmed that the polymer-fiber composite film according to the present embodiment had improved mechanical strength while maintaining heat resistance.

Claims (11)

adding polymer fine particles and an organic solvent to an aqueous solution in which cellulose nanofibers are dispersed;
stirring the aqueous solution to form a Pickering emulsion; and
Including; obtaining polymer-fiber composite particles from the aqueous solution;
The organic solvent is benzene, chlorobenzene, 1,2-dichlorobenzene, o-xylene, m-xylene, p -Containing at least one selected from the group consisting of p-xylene and toluene,
Method for producing polymer-fiber composite particles.
According to claim 1,
The cellulose nanofibers are non-functionalized cellulose nanofibers, a method for producing polymer-fiber composite particles.
According to claim 1,
The organic solvent is added in an amount of 1 μl to 100 μl to 1 ml of an aqueous solution in which cellulose nanofibers are dispersed, a method for producing polymer-fiber composite particles.
According to claim 1,
The polymer fine particles are added in an amount of 1 mg to 20 mg per 1 ml of an aqueous solution in which cellulose nanofibers are dispersed, a method for producing polymer-fiber composite particles.
According to claim 1,
The size of the polymer fine particles is 0.1 ㎛ to 300 ㎛, a method for producing a polymer-fiber composite particles.
According to claim 1,
The concentration of the cellulose nanofibers in the aqueous solution is 0.1 g / L to 10 g / L, a method for producing polymer-fiber composite particles.
A polymer-fiber composite film comprising the composite particles prepared by claim 1.
According to claim 7,
Young's modulus of the composite film is 0.60 GPa or more, polymer-fiber composite film.
According to claim 7,
Tensile strength of the composite film is 19.0 MPa or more, polymer-fiber composite film.
A method for producing a polymer-fiber composite film comprising the steps of thermally compressing the composite particles prepared by claim 1.
According to claim 10,
The thermal compression is carried out at 100 ℃ to 180 ℃ and 10 MPa to 30 MPa, a method for producing a polymer-fiber composite film.

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