KR20190062101A - Cellulose nanofibrils and manufacturing method thereof - Google Patents

Abstract

A method for manufacturing cellulose nanofibrils and cellulose nanofibrils manufactured thereby are provided. The method for manufacturing cellulose nanofibrils may comprise the steps of pretreating pulp and manufacturing cellulose nanofibrils with the pretreated pulp. The present invention provides a method for manufacturing low-cost and high-efficiency cellulose nanofibrils.

Description

TECHNICAL FIELD [0001] The present invention relates to a cellulose nano-

The present invention relates to a cellulose nano-fibril and a method for producing the same.

Cellulose nanofibrils (CNF) made from wood and non-wood pulp fibers morphologically have a diameter of less than 100 nm and a length of several micrometers. Because it is a cellulose-based material derived from plants, it is environmentally friendly and biodegradable. Due to its high strength properties, it can be applied to many fields such as strength reinforcing materials for polymer films, transparent films, hydrogels, and rheological properties improvers.

However, when manufacturing the cellulose nano-fibrils, there is a disadvantage that the production cost is very high due to high energy consumption. Processes for lowering the production energy of the cellulose nano-fibrils through appropriate pretreatment have been researched and developed. However, the cellulose nano-fibrils prepared by the process have a large average diameter of 100 nm and a large diameter distribution, It is difficult to secure quality. In addition, there is a disadvantage in that the solvent system is complicated by the process of replacing the pulp with a solvent.

In order to solve the above-mentioned problems, the present invention provides a method for producing low cost and high efficiency cellulose nano fibrils.

The present invention provides cellulose nano-fibrils produced according to the above-mentioned production method.

Other objects of the present invention will become apparent from the following detailed description and the accompanying drawings.

The method for producing cellulose nano-fibrils according to embodiments of the present invention may include a step of pretreating the pulp and a step of producing the cellulose nano-fibril with the pretreated pulp.

The pretreatment may be performed without a solvent replacement step to remove moisture contained in the pulp.

Wherein the pretreatment step comprises carboxymethylation of the pulp, wherein the carboxymethylation step comprises alkalizing by reacting the pulp with an alkaline agent, and etherifying the pulp with a halogen carboxylic acid.

The etherification step may proceed after the alkalization step.

The alkali agent and the halogen carboxylic acid may be dissolved in a single solvent, and the solvent may be isopropanol.

The alkalization step may be carried out at 25 to 45 DEG C for 20 to 40 minutes.

The etherification step may be carried out at 55 to 75 占 폚 for 50 to 70 minutes.

Wherein the pre-treating step further comprises washing the carboxymethylated pulp, wherein the step of washing the carboxymethylated pulp comprises washing the carboxymethylated pulp with a carboxymethylated pulp having an electrical conductivity of 10 to 30 μS / cm, 8 < / RTI >

The step of preparing the cellulose nanofibrils may include diluting the carboxymethylated pulp and homogenizing the diluted pulp to nanofibrillate.

The homogenization may be carried out using one or more methods selected from a grinder, a homogenizer, and a microfluidizer.

The cellulose nano-fibrils according to the embodiments of the present invention can be produced according to the above-described manufacturing method.

The prepared cellulose nano-fibrils may have a uniform diameter of 5 to 20 nm.

The method of manufacturing the cellulose nano-fibrils according to the embodiments of the present invention is simple in process and can reduce the cost by using a single solvent.

The method for producing cellulose nano-fibrils according to the embodiments of the present invention can produce uniform cellulose nano-fibrils having a small diameter even with a small energy.

1 is a flow chart of a method for producing cellulose nano-fibrils according to an embodiment of the present invention.
2 shows the carboxyl group content of the carboxymethylated pulp produced under the reaction conditions according to Example 1 of the present invention.
Fig. 3 shows the content of carboxyl groups and moisture according to the pulp content according to Experiment 1 of Example 2 of the present invention. Fig.
Fig. 4 shows conductivity measurement results due to the influence of moisture content on the carboxyl group according to Experiment 2 of Example 2 of the present invention.
Fig. 5 shows the moisture content and the carboxyl content in the second experiment according to the second embodiment of the present invention.
Figure 6 shows the carboxyl group content and total moisture content as a function of isopropanol capacity according to Experiment 3 of Example 2 of the present invention.
Figure 7 shows the carboxyl group content of the pulp prepared according to Example 3 of the present invention.
FIG. 8 shows the low shear viscosity according to the number of passes of three reactions according to the embodiment of FIG.
FIG. 9 shows a field emission scanning electron microscope (FE-SEM) image of the carboxymethylated cellulose nano-fibril according to the embodiment of FIG.
Figure 10 shows the TSI of the diluted cellulose nano-fibrils according to the embodiment of Figure 7 over time.

Hereinafter, the present invention will be described in detail with reference to examples. The objects, features and advantages of the present invention will be easily understood by the following embodiments. The present invention is not limited to the embodiments described herein, but may be embodied in other forms. The embodiments disclosed herein are provided so that the disclosure may be thorough and complete, and that those skilled in the art will be able to convey the spirit of the invention to those skilled in the art. Therefore, the present invention should not be limited by the following examples.

The sizes of the elements in the figures, or the relative sizes between the elements, may be exaggerated somewhat for a clearer understanding of the present invention. In addition, the shape of the elements shown in the drawings may be somewhat modified by variations in the manufacturing process or the like. Accordingly, the embodiments disclosed herein should not be construed as limited to the shapes shown in the drawings unless specifically stated, and should be understood to include some modifications.

1 is a flow chart of a method for producing cellulose nano-fibrils according to an embodiment of the present invention.

Referring to FIG. 1, a method for producing a cellulose nano-fibril may include a step of pretreating pulp and a step of preparing cellulose nano-fibril with the pretreated pulp.

The pretreatment step may comprise the steps of preparing the pulp, carmethylating the prepared pulp, and washing the carboxymethylated pulp.

In the pulp preparation step, the pulp may be subjected to dehydration without solvent substitution. The pulp preparation step, which is only dehydrated, can reduce the cost associated with the solvent used in the conventional solvent replacement. The pulp may be made to be 10 to 20 wt%, particularly 22 wt%, through the preparation step.

The carboxymethylation step may be a pretreatment step in which a carboxymethyl group is attached to the pulp surface so that an electric repulsive force acts, and may include an alkalization step and an etherification step, and the etherification step may be performed after the alkalization step.

The alkalizing step is the first step of the carboxymethylation, and the prepared pulp can be alkalized by reacting with an alkaline agent such as sodium hydroxide. The alkalization can proceed by a reaction between sodium hydroxide and the hydroxyl group of the pulp as shown in Equation [1].

ROH + NaOH ↔ RONa + H ₂ O [1]

Where R is the backbone of the pulp fibers.

As the reaction proceeds, the degree of alkalization of the pulp increases, and as the degree of alkalization increases, the reactivity of carboxymethylation can be increased. The alkalization step may be carried out at 25 to 45 ° C for 20 to 40 minutes, more specifically at 35 ° C for 30 minutes.

The etherification step is the second step of the above-mentioned carboxymethylation, and the alkalized pulp can be reacted with a halogen carboxylic acid such as monochloroacetic acid (MCA) according to the formula [2].

RONa + ClCH ₂ COONa ↔ ROCH ₂ COONa + NaCl [2]

The etherification step may be carried out at 55 to 75 ° C for 50 to 70 minutes, more specifically at 65 ° C for 60 minutes.

The sodium hydroxide in the alkalizing step and the monochloroacetic acid in the etherification step may be dissolved in a single solvent and the reaction may proceed, and the single solvent may be, for example, isopropanol.

The carboxymethyl group substituted on a hydroxyl group (-OH) position in the fiber pulp through the carboxymethylated is -CH ₂ COO ionized ^- can be assigned an anionic to the fiber surface due to the presence of the form. Depending on the degree of substitution of the carboxymethyl group, the solubility in water and the viscosity characteristics may vary. The carboxymethylation can increase the moisture retention rate and significantly reduce the rate of crystallinity to amorphous cellulose. In addition, the increase of the anionic property can finally reduce the energy consumed in the production of the cellulose nanofibrils by the mechanical treatment.

In the washing step, the reaction solvent is removed and the pulp can be washed until the electric conductivity is 10 to 30 μS / cm and the pH is 6 to 8, specifically, the electrical conductivity is 20 μS / cm, and the pH is 7 .

The step of preparing the cellulose nanofibrils may include diluting the carboxymethylated pulp and homogenizing the diluted pulp to nanofibrillate.

The step of diluting the carboxymethylated pulp may be carried out by suspending the carboxymethylated pulp. The suspension may be adjusted to 0.5 to 2.5% by weight, specifically 1.5% by weight.

The nanofibrillating step can mechanically homogenize the suspension to produce the cellulose nanofibrils. The homogenization may be performed using one or more methods selected from a grinder, a homogenizer, and a microfluidizer.

The cellulose nano-fibrils prepared according to the above-described preparation method may have a uniform diameter of about 5 to 20 nm, particularly about 12 to 15 nm.

[Preparation of experiment]

In order to investigate the effect of chemical pretreatment on the production of cellulose nanofibrils, never-dried eucalyptus kraft pulp is used as a raw material. The pulp was washed with deionized water before carboxymethylation. The chemical composition of the pulp fibers was measured according to the TAPPI method (T 203 om-93). The pulp consisted of 79.4% ± 0.6% cellulose, 18.8% ± 0.2% hemicellulose and a small amount of lignin and ash.

(Sigma Aldrich, 99.0%, MCA), ethanol (Duksan Reagents, 99.9%), sodium hydroxide (Samchun chemical, 98.0%), isopropanol (Duksan Reagents, 99.5%), and methanol Duksan Reagents, 99.8%) was used without further purification.

[Example 1-Comparison of Carboxymethylation Reactivity]

[Experimental Conditions]

Four experiments were conducted to investigate the effect of reaction sequence and solvent type on the reactivity of carboxymethylation. Table 1 shows the reaction conditions tested for carboxymethylation of the pulp.

Experiment

Solvent
exchange of pulp Reaction 1
(30 min, 35 < 0 > C) Reaction 2
(60 min, 65 < 0 > C)
Chemical and solvent
One

Yes
MCA in 200mL IPA
300 mL of NaOH
MeOH & IPA
2
No

MCA in 200mL IPA
300 mL of NaOH
MeOH & IPA
3

No
300 mL of NaOH
MeOH & IPA
MCA in 200mL IPA
4
No

NaOH in 300 mL IPA
MCA in 200mL IPA

In Experiment 1, the pulp fibers dissociated in accordance with the conventional method were solubilized with ethanol by washing three times with 1 g of pulp in 100 mL of ethanol. After each solvent displacement step, the pulp was filtered using a vacuum filtration system at a concentration of 18% by weight. The fibers were then subjected to a first reaction in which 200 ml of isopropanol, in which 0.96 mmol / g of monochloroacetic acid was dissolved at 35 占 폚 for 30 minutes, was impregnated. A second reaction was conducted in which 300 mL of an isopropanol-methanol mixture (in which the ratio of isopropanol to methanol was 4: 1 by volume) in which 3.68 mmol / g sodium hydroxide had been dissolved was added to the reaction chamber and stirred at 65 ° C for 60 minutes. Experiment 1 is known as a typical method for preparing carboxymethylated cellulosic nanofibrils.

In Experiment 2, the first reaction and the second reaction were carried out in the same manner as Experiment 1 without solvent substitution treatment on the pulp. The concentration of the non-solvent-substituted pulp was 22% by weight. Experiment 3 was preceded by prealtering with a mixed solvent before etherification to investigate the effect of the reaction sequence. Experiment 4 consisted of carboxymethylation following successive alkalization in isopropanol. After the reaction, the carboxymethylated pulp fibers were washed with deionized water until the pH reached 7 + 0.5 and the conductivity reached ≤20 μS / cm.

[Measurement of carboxyl group content]

The carboxyl group content of the carboxymethylated pulp was determined using the conductivity titration method. Briefly, 1 g of pulp was converted to a proton form until all acid groups had received H ⁺ as counterion, and then titrated with 0.05 mol / L sodium hydroxide. The total amount of carboxyl groups was calculated according to equation [3].

Carboxyl group content = (C _NaOH x V _NaOH ) / w [3]

Where C _NaOH , V _NaOH, and w represent the concentration of sodium hydroxide solution, the volume of sodium hydroxide solution, and the oven dry weight of the sample, respectively.

[result]

2 shows the carboxyl group content of the carboxymethylated pulp produced under the reaction conditions according to Example 1 of the present invention.

Referring to FIG. 2, as in Experiments 2, 3 and 4 of Table 1, the case of the non-solvent-substituted pulp was higher than that of the solvent-substituted pulp as in Experiment 1. FIG. The solvent replacement process was carried out using a large amount of ethanol, which significantly increases the production cost of the cellulose nanofibrils. It is clear that the solvent substitution process does not provide benefits for the carboxymethylation reaction and cost savings.

In Experiment 3, when alkalization was first carried out without the solvent substitution process, the carboxyl content was increased to 150 μmol / g. As in Experiment 4, the highest carboxyl content of 310 μmol / g was obtained when isopropanol was used as the sole solvent for etherification after pre-alkalization of non-solvent-substituted pulp. As a result, it can be seen that the isopropanol exhibits substantially better reaction activity than the mixed solvent of methanol and isopropanol.

Since the liquid phase surrounding the cellulose fibers contains concentrated sodium hydroxide and water, a small amount of water derived from the pulp will be dissolved in isopropanol containing sodium hydroxide. The high-capacity isopropanol has less moisture and sodium hydroxide than the liquid phase surrounding the fiber surface. Thus, a highly concentrated alkali solution can be present around the fibers to increase alkalization and carboxymethylation. In addition, the use of isopropanol for carboxymethylation results in less side reactions because the low hydroxyl group activity of the nonpolar solvent provides a resistant environment for monochloroacetic acid.

[Example 2 - Evaluation of influence by pulp concentration and moisture]

[Experiment 1]

To determine the effect of pulp concentration and moisture content on the carboxymethylation reaction, the amount of pulp and water in the solvent was controlled. The amount of the pulp was increased from 1 g to 4 g while keeping the total volume of the reaction tank constant at 500 mL in the same manner as in Example 1. Isopropanol and a solvent-free pulp at a concentration of 22% by weight were used and etherified after the pre-alkalization.

[Experiment 2]

Additionally, to further assess the effect of moisture content on the reaction, the amount of pulp was kept constant at 1 g and water was added to the solvent to 7.5 w / v%.

[Experiment 3]

Table 2 shows four experimental conditions in which the pulp concentration and moisture content were varied in order to examine how the amount of isopropanol and pulp affects the carboxymethylation reaction. The pulp concentration is in the range of 0.2 to 1.33 w / v% and the water content is in the range of 0.70 to 4.84 w / v%.

Experiment

Total volume of IPA, mL

Pulp consistency, w / v%
Water contents, w / v%
Pulp, 1 g
Pulp, 4g
Pulp, 1 g
Pulp, 4g
One
500
0.20
0.80
0.70
2.85
2
400
0.25
1.00
0.87
3.60
3
350
0.28
1.14
1.00
4.12
4
300
0.33
1.33
1.54
4.84

[result]

Fig. 3 shows the content of carboxyl groups and moisture according to the pulp concentration according to Experiment 1 of Example 2 of the present invention. Fig. When the non-solvent-substituted pulp is used as a starting material for carboxymethylation, the pulp concentration and the moisture contained in the pulp may affect the reaction rate.

Referring to FIG. 3, the amount of pulp was increased from 1 g to 4 g, corresponding to an increase of the pulp concentration from 0.2 w / v% to 0.8 w / v%. As the amount of pulp increased, the content of water in the solvent increased to 2.85 w / v%. Also, the amount of carboxyl groups was continuously increased according to the pulp concentration. The increase in the pulp concentration is accompanied by an increase in the moisture content, which can affect the reaction rate.

FIG. 4 shows the results of conductivity measurement as an effect of moisture content on the carboxyl group according to Experiment 2 of Example 2 of the present invention, and FIG. 5 shows the results of comparing the moisture content and the carboxyl group content according to Experiment 2 of Example 2 of the present invention .

5, when the amount of pulp was kept constant at 1 g and water was added to the solvent to 7.5 w / v%, when the moisture content of isopropanol was increased to 4.0 w / v%, the content of carboxyl groups Was maintained at 300 μmol / g or more. However, when the water content was further increased to 4.0 w / v% or more, the content of the carboxyl group was decreased. From the results, it can be seen that when the pulp concentration increases, the carboxymethylation reaction increases, but when the moisture content increases with the pulp, the carboxymethylation decreases. Therefore, it can be judged that it is necessary to appropriately adjust the water content in the system.

Figure 6 shows the carboxyl group content and total moisture content as a function of isopropanol capacity according to Experiment 3 of Example 2 of the present invention.

Referring to FIG. 6, when 1 g of pulp was used, the carboxymethylation reaction decreased as the total isopropanol capacity increased. The pulp concentration increased with decreasing reaction medium and the moisture content was less than 1.54 w / v%. However, when 4 g of pulp was used, particularly when 350 or 300 mL of isopropanol was used, the carboxyl content also decreased as the isopropanol volume decreased. Both conditions showed a water content of at least 4.0 w / v%.

[Example 3 - Preparation and Characterization of Cellulose Nanofibrils]

[Assessment Methods]

Carboxymethylated pulp fibers were used to prepare a suspension of cellulose nanofibrils. Prior to grinding, the concentration of the pulp suspension was adjusted to 1.5 wt.% And a sample of 1800 mL of slurry was selected for the preparation of the cellulose nanofibrils. The pulp suspension was passed through a grinder (Super Masscolloid, Masuko Sangyo Co., Ltd., Japan). The working speed is 1500rpm and the clearance is -80μm. Samples of the cellulosic nanofibril suspension were collected for further study after grinding at a constant number of passes. In addition to the grinder, a homogenizer or a microfluidizer can be used as a homogenizer for nanofibrilization.

To compare the degree of fibrillation of the pulp fibers produced under different reaction conditions, low shear viscosity was measured (Brookfield DV2T-LV). Generally, as the number of grinder passes increased, the viscosity increased until the pulp fibers reached the ballast when they were fully nanofibrillated. The morphological properties of the fibrillated cellulose nanofibrils can be examined using field emission scanning electron microscopy (FE-SEM, Carl Zeiss, SIGMA, UK).

To prepare a cellulose nano-fibril specimen, the surface of the silicon wafer was treated with ultraviolet light to change the surface properties from hydrophobic to hydrophilic. Cationic diallyldimethylammonium chloride (P-DADMAC) was applied as an anchoring polymer onto the surface of the silicon wafer. The diluted cellulosic nano-fibril (0.01%) suspension was sputtered using a spin coater (ACE-200, Korea). The fusion reaction of the cellulose nanofibrils can be examined using a Turbiscan Aging Station (Formulation Inc., France) for measuring the light transmittance of near-infrared light (? Air = 880 nm) through a sample glass bottle . The total analysis period and the analysis interval were 60 minutes and 5 minutes, respectively. According to Eq. [4], the transmission and back scattering results are converted to Turbiscan stability index (TSI) as a function of time.

[4]Turbiscan stability index (TSI) =

[4]

Where xi is the mean backscattering for each measurement, xBS is the mean value of xi, and n is the number of scans.

[Experimental Conditions]

Three carboxylation reactions were performed to evaluate the properties of cellulose nanofibrils with different carboxyl group contents. Table 3 shows the carboxymethylation conditions and carboxyl content of the carboxymethylated pulp.

Reaction
Pulp, g Solvent exchange of pulp
Reaction
solvent
MCA,
mmol / g
NaOH,
mmol / g Carboxyl
content,
Μmol / g
One
50
Yes
MeOH & IPA
2.88
11.04
607
2
50
Yes
MeOH & IPA
1.92
7.36
370
3
50
No
IPA
0.96
3.68
570

Referring to Table 3, the first and second reactions were carried out using a solvent-substituted pulp in a mixed solvent containing two to three times more monochloroacetic acid and sodium hydroxide than the third reaction. In the third reaction, 50 g of a non-solvent-substituted pulp sample was used and only isopropanol was used as the only reaction solvent. The pulp concentration of the reaction was 1.0 w / v% and the water content was 3.6 w / v%.

[result]

Figure 7 shows the carboxyl group content of the pulp prepared according to Example 3 of the present invention.

Referring to FIG. 7, it can be seen that the carboxymethylation of the third reaction using only isopropanol without solvent substitution is as effective as the first reaction using three times the monochloroacetic acid and the sodium hydroxide of the third reaction.

FIG. 8 shows the low shear viscosity according to the number of passes of three reactions according to the embodiment of FIG.

Referring to FIG. 8, the low shear viscosity of pulp ground in a masscolloid was measured to estimate the fibrillation level as a function of the number of grinding passes. Clearly, the low shear viscosity increased with the number of passes for all three samples of the first reaction, the second reaction and the third reaction, reaching the ballast and indicating complete fibrillation of the pulp to the cellulose nanofibrils . The third reaction with a carboxyl content of 570 占 퐉 ol / g and the first reaction pulp with a carboxyl content of 607 占 퐉 ol / g reached the stabilizer after five grinding passes. For the second reaction pulp with a carboxyl content of 370 μmol / g, 11 grinding was required to reach the stabilizer for low shear viscosity. Since the carboxyl content eventually changed the electrostatic repulsive force between the fibrils, the number of grinding passes was largely affected by the amount of carboxyl groups introduced into the carboxymethylation, regardless of the reaction conditions, the fibrillation of the carboxymethylated pulp Receiving.

FIG. 9 is a field emission scanning electron microscope (FE-SEM) image of a carboxymethylated cellulose nano-fibril according to the embodiment of FIG. 7, wherein (a) shows a first reaction with a carboxyl group content of 607 μmol / g, (C) is an image of a third reaction having a carboxyl group content of 570 占 퐉 ol / g.

Table 4 shows the width and standard deviation of the cellulose nanofibrils. The morphology and width of the cellulose nanofibrils were examined using a field emission scanning electron microscope and image analysis method, respectively.

Reaction 1
Reaction 2
Reaction 3
Width, nm
13.5
14.5
12.4
St. dev.
3.31
3.16
2.82

Referring to Figures 9 and Table 4, the average width of the cellulose nanofibrils was very similar from 12.4 nm to 14.5 nm. The sample ground (second reaction) ground 11 times with a grinder showed a larger diameter than the other two samples.

Figure 10 shows the TSI of the diluted cellulose nano-fibrils according to the embodiment of Figure 7 over time.

Referring to FIG. 10, the turbidity stability index was determined to evaluate suspension stability. The increase in the turbidity scan stability index means that precipitation of the dispersed phase on the vial bottom occurs more rapidly. Well-dispersed fibrils that remain stable in the suspension show a more uniform quality of the cellulose nanofibrils. As expected, the dispersion stability depends on the carboxyl content. Cellulose nanofibrils with the lowest carboxyl content settle faster than the other two cellulosic nanofibrils. These results suggest that the carboxyl content is an important factor in the stability of the cellulose nanofibrils.

Hereinafter, specific embodiments of the present invention have been described. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. Therefore, the disclosed embodiments should be considered in an illustrative rather than a restrictive sense. The scope of the present invention is defined by the appended claims rather than by the foregoing description, and all differences within the scope of equivalents thereof should be construed as being included in the present invention.

Claims (12)

Pretreating the pulp; And
And preparing cellulose nano-fibrils from the pretreated pulp. The method according to claim 1,
The pre-
Wherein the pulp is carried out without a solvent substitution process for removing water contained in the pulp. The method according to claim 1,
The pre-
Carboxymethylating the pulp,
Wherein the carboxymethylation step comprises:
Reacting the pulp with an alkaline agent to alkalize and reacting the pulp with a halogen carboxylic acid to etherify the cellulose nano-fibril. The method of claim 3,
Wherein the etherification step proceeds after the alkalization step. ≪ RTI ID = 0.0 > 21. < / RTI > The method of claim 3,
The alkali agent and the halogen carboxylic acid can be dissolved in a single solvent,
Wherein the solvent is isopropanol. ≪ RTI ID = 0.0 > 21. < / RTI > The method of claim 3,
Wherein the alkalizing step is carried out at 25 to 45 DEG C for 20 to 40 minutes. The method of claim 3,
Wherein the etherification step is carried out at 55 to 75 DEG C for 50 to 70 minutes. The method of claim 3,
Wherein the pretreatment step further comprises washing the carboxymethylated pulp,
The step of washing the carboxymethylated pulp comprises:
Wherein the carboxymethylated pulp has an electrical conductivity of 10 to 30 μS / cm and is washed until a pH of 6 to 8 is reached. The method according to claim 1,
Wherein the step of preparing the cellulose nanofibrils comprises:
Diluting the carboxymethylated pulp, and homogenizing the diluted pulp to form nanofibrils. The method of manufacturing a cellulose nano-fibril according to claim 1, 10. The method of claim 9,
Wherein the homogenization uses at least one method selected from a grinder, a homogenizer, and a microfluidizer. A cellulose nano-fibril produced according to the method of any one of claims 1 to 10. 12. The method of claim 11,
Wherein the cellulose nano-fibrils have a uniform diameter of 5 to 20 nm.

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