KR20110118567A - Fluorinated cellulose acetate, the fabrication method thereof, and the piezoelectric paper obtained therefrom - Google Patents

Abstract

로 이루어진 군으로부터 선택되는 어느 하나이고, 여기서 상기 R'는 탄소 원자 1개 내지 20개를 가지는 직쇄 또는 측쇄 알킬기, 탄소 원자 6개 내지 8개를 가지는 아릴기 또는 탄소원자 6개 내지 8개의 아랄킬기이며, 상기 알킬기는 치환되지 않거나 1개 내지 41개의 불소 원자로 치환되고, 상기 아릴기는 치환되지 않거나 1개 내지 9개의 불소 원자로 치환되며, 상기 아랄킬기는 치환되지 않거나 1개 내지 9개의 불소 원자로 치환된다.The present invention relates to a fluorinated cellulose acetate obtained by reacting cellulose acetate with a fluorine compound represented by the following formula (1), a piezoelectric paper using the same, and a method for producing the same. Eliminates the problem of low piezoelectric charge constants, which are the weakest disadvantages of polymers, to provide piezoelectric paper with large deformation, low energy consumption, fast responsiveness, high force, and low manufacturing cost. can do:
[Formula 1]
RX
Where
R is a straight or branched chain alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 8 carbon atoms or an aralkyl group having 6 to 8 carbon atoms, wherein the alkyl group is selected from 1 to 41 fluorine atoms Substituted, the aryl group is substituted with 1 to 9 fluorine atoms, and the aralkyl group is substituted with 1 to 9 fluorine atoms; And
X is -OH, -CN, -CHO, -COCl, -NH ₂ , -SO ₂ Cl, -COOH, -COOR ', -Cl, -Br, -I, -COOCOR' and

Is any one selected from the group consisting of wherein R 'is a straight or branched chain alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 8 carbon atoms or an aralkyl group having 6 to 8 carbon atoms Wherein the alkyl group is unsubstituted or substituted with 1 to 41 fluorine atoms, the aryl group is unsubstituted or substituted with 1 to 9 fluorine atoms, and the aralkyl group is unsubstituted or substituted with 1 to 9 fluorine atoms .

Description

Fluorinated cellulose acetate, the fabrication method, and the piezoelectric paper obtained therefrom}

The present invention relates to a fluorinated cellulose acetate, a method for producing the same, and a piezoelectric paper obtained therefrom, and more particularly, to a fluorinated cellulose acetate obtained by bonding a fluorine compound to an acetized cellulose, that is, cellulose acetate, and a method for producing the same. A piezoelectric paper obtained therefrom, in particular, the piezoelectric paper is a piezoelectric charge constant (Piezoelectric charge constant) by arranging molecules containing fluorine in a predetermined direction through the polling and / or stretching of fluorine compounds bonded to cellulose or cellulose acetate It is a piezoelectric paper with improved.

In general, fibers present in natural trees and plants are composed of cellulose, lignin, and hemicellulose. Cellulose produces about 150 billion tons annually in nature and is the richest organic substance in nature.

More than 100 years ago, Jacques and Pierre Curie were found in piezoelectricity in medical, military, industrial, consumer electronics, and exploration after discovering that they had piezoelectricity. come.

The piezoelectric effect refers to a phenomenon in which pressure or force is applied to the piezoelectric material to generate a voltage on the surface of the piezoelectric material, and conversely, deformation occurs depending on the size of the piezoelectric material when a voltage is applied.

Piezoelectric materials also have a pyroelectricity, which refers to the generation of voltage on the surface of the piezoelectric material in proportion to changes in temperature around the piezoelectric material. In particular, as piezoelectric ceramics were developed in the 1940's, application technologies using them were widely developed.

Piezoelectric ceramics were developed in the 1940s by piezoelectric ceramics of barium-titanium oxide (BaTiO ₃ ), and in the 1950s by piezoelectric ceramics of lead-zirconate-titanium oxide (PZT). The study began.

Piezoelectric ceramics have the advantage of having a rigid and dense structure, chemically inert, environmentally resistant in a humid or wide temperature range, and mechanically and electrically accurate arrangement. However, ceramics have the disadvantages of being brittle, heavy, and unable to bend. In particular, research is being conducted on a new piezoelectric ceramic that does not use lead because lead is harmful to the human body.

Polyvinylidene fluoride (PVDF), representative of piezoelectric plastics or piezoelectric polymers, was found to have piezoelectric properties in 1969 by Kawai. Piezoelectric polymers are thin engineering plastics compared to piezoelectric ceramics, which are not only simpler than other sensor materials, but also flexible, large-area, impact-resistant, unbreakable, lightweight, and have good acoustic properties for ultrasonic applications. It has the advantage of good productivity.

However, PVDF has a limitation in use temperature, is not suitable for devices using DC, and has a disadvantage in that piezoelectric properties are much lower than piezoelectric ceramics. Due to these shortcomings, it has not been very successful commercially.

As described above, the piezoelectric polymers studied so far have the advantages of being flexible, fast response and relatively large displacement, but low piezoelectric properties, high manufacturing cost, and particularly biodegradable, so that industrial wastes are generated. .

After obtaining high piezoelectric charge constants by bipolar organic molecule alignment in IBM in the 1980s, many researchers were able to uniformly align various molecules to polymers to obtain high piezoelectric charge constants, but commercialization was unsuccessful. The main reason was the temporal stability. This time stability is that when the bipolar molecules are aligned in one direction, the piezoelectric effect disappears over time due to the property that the molecules return to the direction in which the natural polarity is canceled over time.

Recently, in the 2000s, it was found that cellulose has biodegradability and piezoelectric properties, and has been actively developed as piezoelectric paper. In particular, piezoelectric paper is being developed by arranging regenerated cellulose in a predetermined direction.

Piezoelectric paper has piezoelectricity similar to that of conventional piezoelectric polymers, and cellulose is biodegradable and biocompatible and thus does not cause pollution. In addition, cellulose piezoelectric paper has excellent heat resistance and can withstand higher temperatures than conventional piezoelectric polymers.

As a prior patent for this, according to Patent Application No. 10-2008-12634 filed by the present inventors, piezoelectric paper and a method for producing the same, the bulk cellulose in sodium hydroxide, DMAc (N, N-Dimethylacetamide) or NMMO ( Adding a solvent of N-methylmorpholine-N-oxide to form a cellulose solution; Spin coating, extruding, or casting the solution to form a thin film in which cellulose fibers are arranged in a predetermined direction; Washing the formed thin film with water to remove remaining solvent; And installing an electrode on the formed cellulose thin film.

According to this prior patent, cellulose paper is a fiber paper (bulky paper), using a solvent such as sodium hydroxide, DMAc (N, N'-dimethylacetamide) or NMMO (N-methylmorpholine-N-oxide) Then, the cellulose pulp is melted to form a cellulose solution. After spin coating, the microfibers are arranged by centrifugal force, and when extruded, the fibers are arranged by the mechanical effect of the pushing direction and the applied tensile force.

The produced cellulose membrane is reacted with water to remove the solvent to regenerate the original cellulose to make a cellulose paper. Applying mechanical stretching to further align the cellulose orientation causes the cellulose fibers to be aligned in the pulling machine direction.

However, the piezoelectric paper manufactured as described above has a problem that piezoelectricity is superior to piezoelectric ceramics, but still has low piezoelectricity, and therefore, there is a limit to use in various industries.

In order to solve the problems of the prior art as described above, the present invention provides a high dielectric constant fluorinated cellulose acetate obtained by using cellulose acetate more reactive than cellulose and reacting it with a fluorine compound and a method for producing the same. For the purpose of

It is also an object of the present invention to provide a piezoelectric paper excellent in piezoelectricity, which is obtained using the fluorinated cellulose acetate of the above high dielectric constant.

The piezoelectric paper of the present invention described above improves the piezoelectric effect, that is, the piezoelectric charge constant, by the polling and / or stretching of fluorine compounds of various sizes bonded on cellulose or cellulose acetate, causing large deformation even at low voltages, and low energy consumption. It is a piezoelectric paper with quick response, low manufacturing price.

The above object of the present invention is achieved by fluorinated cellulose acetate obtained by reacting cellulose acetate with a fluorine compound represented by the following formula (1):

[Formula 1]

RX

Where

R is a straight or branched chain alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 8 carbon atoms or an aralkyl group having 6 to 8 carbon atoms, wherein the alkyl group is selected from 1 to 41 fluorine atoms Substituted, the aryl group is substituted with 1 to 9 fluorine atoms, and the aralkyl group is substituted with 1 to 9 fluorine atoms; And

로 이루어진 군으로부터 선택되는 어느 하나이고, 여기서 상기 R'는 탄소 원자 1개 내지 20개를 가지는 직쇄 또는 측쇄 알킬기, 탄소 원자 6개 내지 8개를 가지는 아릴기 또는 탄소원자 6개 내지 8개의 아랄킬기이며, 상기 알킬기는 치환되지 않거나 1개 내지 41개의 불소 원자로 치환되고, 상기 아릴기는 치환되지 않거나 1개 내지 9개의 불소 원자로 치환되며, 상기 아랄킬기는 치환되지 않거나 1개 내지 9개의 불소 원자로 치환된다.X is -OH, -CN, -CHO, -COCl, -NH ₂ , -SO ₂ Cl, -COOH, -COOR '-Cl, -Br, -I, -COOCOR' and

Is any one selected from the group consisting of wherein R 'is a straight or branched chain alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 8 carbon atoms or an aralkyl group having 6 to 8 carbon atoms Wherein the alkyl group is unsubstituted or substituted with 1 to 41 fluorine atoms, the aryl group is unsubstituted or substituted with 1 to 9 fluorine atoms, and the aralkyl group is unsubstituted or substituted with 1 to 9 fluorine atoms .

The fluorine compound represented by Formula 1 is CF ₃ COOH (trifluoroacetic acid), (CF ₃ CO) ₂ O (trifluoroacetic anhydride trifluoroacetic anhydride), CF ₃ CN (trifluoroacetonitrile trifluoroacetonitrile), CF ₃ COCl (trifluoroacetyl chloride), CF ₃ C ₂ H ₂ O (trifluoroepoxypropane trifluoroepoxypropane), CF ₃ CH ₂ OH (trifluoroethanol trifluoroethanol), CF ₃ CF ₂ CHFOH (hexafluoro Lopropanol hexafluoropropanol), C ₆ F ₅ NH ₂ (pentafluoroaniline pentafluoroaniline), C ₆ F ₅ CHO (pentafluorobenzaldehyde pentafluorobenzaldehyde), C ₆ F ₅ SO ₂ Cl (pentafluorobenzenesulfonyl chloride) _{, C 6 F 5 CO 2 H} ( pentafluoroethyl acid _{pentafluorobenzoic acid), C 6 F 5} CH 2 OH ( pentafluorophenyl benzyl alcohol _{pentafluorobenzyl alcohol), C 6 F 5} CH 2 Br ( bromide pentafluoropropane Benzyl _{pentafluorobenzyl bromide), CF 3 CF 2} I ( penta iodine ethane pentafluoroiodoethane) _{fluoroalkyl, ICH 2 (CF 2) 3} CHF 2 ( iodo-pentane octafluoroiodopentane), as octafluoro _{F 2 CH (CF 2) 3} CH 2 OH ( Octafluoropentanol octafluoropentanol), heptadecafluoroundecyliodide, and mixtures thereof.

It is also an object of the present invention to poll, stretch, or poll and stretch the fluorinated cellulose acetate; Or by piezoelectric paper obtained by polling, stretching or polling and stretching and deacetylation reaction.

The piezoelectric charge constant d31 of the piezoelectric paper is at least 50 pC / N, preferably at least 100 pC / N, more preferably at least 150 pC / N.

In addition, an object of the present invention is achieved by a method for producing fluorinated cellulose acetate comprising the step of reacting cellulose acetate with a fluorine compound represented by the following formula (1).

[Formula 1]

RX

Where

R is a straight or branched chain alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 8 carbon atoms or an aralkyl group having 6 to 8 carbon atoms, wherein the alkyl group is selected from 1 to 41 fluorine atoms Substituted, the aryl group is substituted with 1 to 9 fluorine atoms, and the aralkyl group is substituted with 1 to 9 fluorine atoms; And

로 이루어진 군으로부터 선택되는 어느 하나이고, 여기서 상기 R'는 탄소 원자 1개 내지 20개를 가지는 직쇄 또는 측쇄 알킬기, 탄소 원자 6개 내지 8개를 가지는 아릴기 또는 탄소원자 6개 내지 8개의 아랄킬기이며, 상기 알킬기는 치환되지 않거나 1개 내지 41개의 불소 원자로 치환되고, 상기 아릴기는 치환되지 않거나 1개 내지 9개의 불소 원자로 치환되며, 상기 아랄킬기는 치환되지 않거나 1개 내지 9개의 불소 원자로 치환된다.X is -OH, -CN, -CHO, -COCl, -NH ₂ , -SO ₂ Cl, -COOH, -COOR ', -Cl, -Br, -I, -COOCOR' and

Is any one selected from the group consisting of wherein R 'is a straight or branched chain alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 8 carbon atoms or an aralkyl group having 6 to 8 carbon atoms Wherein the alkyl group is unsubstituted or substituted with 1 to 41 fluorine atoms, the aryl group is unsubstituted or substituted with 1 to 9 fluorine atoms, and the aralkyl group is unsubstituted or substituted with 1 to 9 fluorine atoms .

The fluorine compound represented by Formula 1 is CF ₃ COOH (trifluoroacetic acid), (CF ₃ CO) ₂ O (trifluoroacetic anhydride trifluoroacetic anhydride), CF ₃ CN (trifluoroacetonitrile trifluoroacetonitrile), CF ₃ COCl (trifluoroacetyl chloride), CF ₃ C ₂ H ₂ O (trifluoroepoxypropane trifluoroepoxypropane), CF ₃ CH ₂ OH (trifluoroethanol trifluoroethanol), CF ₃ CF ₂ CHFOH (hexafluoro Lopropanol hexafluoropropanol), C ₆ F ₅ NH ₂ (pentafluoroaniline pentafluoroaniline), C ₆ F ₅ CHO (pentafluorobenzaldehyde pentafluorobenzaldehyde), C ₆ F ₅ SO ₂ Cl (pentafluorobenzenesulfonyl chloride) _{, C 6 F 5 CO 2 H} ( pentafluoroethyl acid _{pentafluorobenzoic acid), C 6 F 5} CH 2 OH ( pentafluorophenyl benzyl alcohol _{pentafluorobenzyl alcohol), C 6 F 5} CH 2 Br ( bromide pentafluoropropane Benzyl _{pentafluorobenzyl bromide), CF 3 CF 2} I ( penta iodine ethane pentafluoroiodoethane) _{fluoroalkyl, ICH 2 (CF 2) 3} CHF 2 ( iodo-pentane octafluoroiodopentane), as octafluoro _{F 2 CH (CF 2) 3} CH 2 OH ( Octafluoropentanol octafluoropentanol), heptadecafluoroundecyliodide, and mixtures thereof.

It is also an object of the present invention to poll, stretch, or poll and stretch the fluorinated cellulose acetate obtained by the process for producing fluorinated cellulose described above; Or polling, stretching or polling and stretching and deacetylating.

In addition, an object of the present invention is achieved by a medical pulse sensor including the piezoelectric paper of the present invention, a piezoelectric paper for radio-frequency identification (RFID), a motor, a power generation equipment, a speaker and the like.

Piezoelectric polymer materials to date have not been very commercially successful, the biggest of which is due to the significantly lower piezoelectric charge constants compared to piezoelectric ceramics. Accordingly, in order to solve the disadvantage of the piezoelectric polymer, the present invention improves the piezoelectric charge constant by binding a fluorine compound to cellulose acetate and arranging functional groups containing fluorine in a direction through polling and / or stretching.

In addition, the problem of temporal stability of piezoelectric charge constant using bipolar molecules, which has been raised as a problem, is solved by a hydrogen bonding network which is a characteristic of cellulose.

As described above, in the present invention, the piezoelectric charge constant by the fluorine compound may be added to the piezoelectric charge constant already possessed by the cellulose, thereby rapidly increasing the piezoelectric charge constant, which is high piezoelectric based on the most abundant and biodegradable cellulose in nature. It will be used in a wider variety of fields because it will enable the development of materials that will work, while at the same time complementing the shortcomings of the piezoelectric polymers and piezoelectric ceramics mentioned above.

In addition, the present invention increases the piezoelectric effect of the cellulose piezoelectric paper to the level that can compete with existing piezoelectric ceramics, it is various sensors, piezoelectric speaker and microphone, RFID tag, ID card, various switches, biomimetic robot, distribution- As it can be applied to various fields such as logistics, micro motors and power generation facilities, its marketability and prospects are expected to be infinite.

1 is a reaction scheme showing an example of a reaction of reacting cellulose acetate with a fluorine compound by a Mitsunobu reaction according to Example 1 of the present invention.
FIG. 2 is FTIR spectra for cellulose acetate of Comparative Example 2 of the present invention and fluorinated cellulose acetate prepared according to Example 1. FIG.
Figure 3 shows the XRD pattern for the cellulose acetate of Comparative Example 2 and the fluorinated cellulose acetate prepared according to Example 1 of the present invention.
Figure 4 shows the results of thermogravimetric analysis of cellulose acetate of Comparative Example 2 of the present invention and fluorinated cellulose acetate prepared according to Example 1.
Figure 5 shows the differential thermogravimetric analysis of the cellulose acetate of Comparative Example 2 and the fluorinated cellulose acetate prepared according to Example 1 of the present invention.
6 and 7 are scanning electron microscope images of fluorinated cellulose acetate prepared according to Example 1 of the present invention.
8 and 9 show EDX patterns for fluorinated cellulose acetate prepared according to Example 1 of the present invention.

The fluorinated cellulose acetate of the present invention is described as follows.

That is, the fluorinated cellulose acetate of the present invention is a fluorinated cellulose obtained by reacting cellulose acetate with a fluorine compound represented by the following formula (1):

[Formula 1]

RX

Where

R is a straight or branched chain alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 8 carbon atoms or an aralkyl group having 6 to 8 carbon atoms, wherein the alkyl group is selected from 1 to 41 fluorine atoms Substituted, the aryl group is substituted with 1 to 9 fluorine atoms, and the aralkyl group is substituted with 1 to 9 fluorine atoms; And

로 이루어진 군으로부터 선택되는 어느 하나이고, 여기서 상기 R'는 탄소 원자 1개 내지 20개를 가지는 직쇄 또는 측쇄 알킬기, 탄소 원자 6개 내지 8개를 가지는 아릴기 또는 탄소원자 6개 내지 8개의 아랄킬기이며, 상기 알킬기는 치환되지 않거나 1개 내지 41개의 불소 원자로 치환되고, 상기 아릴기는 치환되지 않거나 1개 내지 9개의 불소 원자로 치환되며, 상기 아랄킬기는 치환되지 않거나 1개 내지 9개의 불소 원자로 치환된다.X is -OH, -CN, -CHO, -COCl, -NH ₂ , -SO ₂ Cl, -COOH, -COOR ', -Cl, -Br, -I, -COOCOR' and

Is any one selected from the group consisting of wherein R 'is a straight or branched chain alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 8 carbon atoms or an aralkyl group having 6 to 8 carbon atoms Wherein the alkyl group is unsubstituted or substituted with 1 to 41 fluorine atoms, the aryl group is unsubstituted or substituted with 1 to 9 fluorine atoms, and the aralkyl group is unsubstituted or substituted with 1 to 9 fluorine atoms .

In general, cellulose is not soluble in conventional solvents such as tetrahydrofuran, as described above, so that cellulose pulp is melted and processed using a solvent such as sodium hydroxide or DMAc or NMMO.

In the present invention, cellulose acetate other than the cellulose is used, which is tetrahydrofurane (THF), chloroform, trichloroethylene, benzene, cellosolve acetate, methyl ethyl ketone, acetone, diacetone alcohol, and ethyl dichloride. Since it is well soluble in common organic solvents such as methylene chloride and the like, it is easy to carry out various chemical reactions. Preferably, tetrahydrofuran is used as the reaction solvent.

These cellulose acetates contain one acetate group and two hydroxy groups per repeating unit, and among these groups, the hydroxy groups are reactive and thus can be used to bind various compounds to cellulose acetate.

In the present invention, a fluorinated cellulose acetate is obtained, in particular, by reacting a compound containing fluorine, that is, a compound containing a reactor capable of reacting with the above-mentioned hydroxyl group as a fluorine compound.

Any fluorine compound including a reactor capable of reacting with a hydroxyl group may be used as the fluorine compound of the present invention. Preferably, the fluorine compound represented by Chemical Formula 1 may be used.

Further, preferably, the fluorine compound represented by Chemical Formula 1 may be CF ₃ COOH (trifluoroacetic acid), (CF ₃ CO) ₂ O (trifluoroacetic anhydride trifluoroacetic anhydride), CF ₃ CN (trifluoro Acetonitrile trifluoroacetonitrile), CF ₃ COCl (trifluoroacetyl chloride), CF ₃ C ₂ H ₂ O (trifluoroepoxypropane trifluoroepoxypropane), CF ₃ CH ₂ OH (trifluoroethanol trifluoroethanol), CF ₃ CF ₂ CHFOH (hexafluoropropanol hexafluoropropanol), C ₆ F ₅ NH ₂ (pentafluoroaniline pentafluoroaniline), C ₆ F ₅ CHO (pentafluorobenzaldehyde pentafluorobenzaldehyde), C ₆ F ₅ SO ₂ Cl (pentafluorobenzenesulphate Pentafluorobenzenesulfonyl chloride), C ₆ F ₅ CO ₂ H (pentafluorobenzoic acid), C ₆ F ₅ CH ₂ OH (pentafluorobenzyl alcohol), C ₆ F ₅ CH ₂ Br ( Pentafluorobenzyl bromide, CF ₃ CF ₂ I (pentafluoroiodoethane), ICH ₂ (CF ₂ ) ₃ CHF ₂ (octafluoroiodopentane octafluoroiodopentane), F ₂ CH (CF ₂ ) ₃ It is preferably any one selected from the group consisting of CH ₂ OH (octafluoropentanol octafluoropentanol), heptadecafluoroundecyliodide and mixtures thereof, more preferably the fluorine represented by the formula (1) The compound is preferably, but not limited to, CF ₃ CF ₂ CHFOH (hexafluoropropanol hexafluoropropanol) or heptadecafluoroundecyliodide.

The piezoelectric paper of the present invention polls, stretches, or polls and stretches the fluorinated cellulose acetate of the present invention; Or piezoelectric paper obtained by polling, stretching or polling and stretching and deacetylation reaction.

The polling process may be performed by various methods such as corona polling, grid polling, contact polling, and the like, and the given voltage is 0.5 depending on the state of the sample, that is, the fluorinated cellulose acetate. It can be achieved by adding kV to 25 kV.

The stretching treatment may be performed by simply stretching the mechanically fluorinated cellulose acetate thin film by 1.1 to 2.5 times, and the mechanical stretching may be performed while warming to a temperature of 60 to 150 ° C., water, alcohol, chloroform, or the like. A fluorinated cellulose acetate thin film may be immersed therein using a solvent such as a halogenated hydrocarbon of to soften the thin film. This stretching treatment may also be performed simultaneously with the deacetylation reaction described below.

In the fluorine compound represented by Formula 1, when R is a lower (1-8 carbon atoms) alkyl group, an aryl group, and an aralkyl group, only the polling treatment or the polling and stretching treatment are performed, and in the case of the higher alkyl group, the stretching treatment is performed. Can only be performed. In the case where R is a higher alkyl group, both polling and stretching can be performed.

When the cellulose fibers and fluorine-containing functional groups of the fluorinated cellulose acetate are arranged in a certain direction by the polling and / or stretching treatment, the piezoelectric charge constant is greatly increased due to the strong electronegativity of the fluorine.

The deacetylation reaction may be carried out by a general deacetylation reaction. For example, in the deacetylation reaction, deacetylation occurs when sodium alkoxide roll is dissolved in alcohol and the fluorinated cellulose acetate thin film is soaked. By this deacetylation reaction, the acetate group in the repeating unit of the fluorinated cellulose acetate of the present invention is deacetylated so that the fluorinated cellulose acetate becomes fluorinated cellulose.

The piezoelectric charge constant (d31) of the piezoelectric paper of the present invention is 50 pC / N to 200 pC / N, preferably 100 pC / N or more, and more preferably 150 pC / N or more.

In addition, the piezoelectric paper of the present invention includes a hydrogen bonding network, that is, the structure of the fluorinated cellulose acetate or the fluorinated cellulose deacetylated thereof includes a hydrogen bonding network and thus, over time, The problem of time stability in the direction of canceling the polarity is avoided. In particular, when the carbon length of a fluorine compound becomes long, the effect is larger.

Next, the above-described method for producing fluorinated cellulose acetate will be described in detail.

Method for producing a fluorinated cellulose acetate of the present invention comprises the step of reacting the cellulose acetate and the fluorine compound represented by the following formula (1).

[Formula 1]

RX

Where

R is a straight or branched chain alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 8 carbon atoms or an aralkyl group having 6 to 8 carbon atoms, wherein the alkyl group is selected from 1 to 41 fluorine atoms Substituted, the aryl group is substituted with 1 to 9 fluorine atoms, and the aralkyl group is substituted with 1 to 9 fluorine atoms; And

로 이루어진 군으로부터 선택되는 어느 하나이고, 여기서 상기 R'는 탄소 원자 1개 내지 20개를 가지는 직쇄 또는 측쇄 알킬기, 탄소 원자 6개 내지 8개를 가지는 아릴기 또는 탄소원자 6개 내지 8개의 아랄킬기이며, 상기 알킬기는 치환되지 않거나 1개 내지 41개의 불소 원자로 치환되고, 상기 아릴기는 치환되지 않거나 1개 내지 9개의 불소 원자로 치환되며, 상기 아랄킬기는 치환되지 않거나 1개 내지 9개의 불소 원자로 치환된다.X is -OH, -CN, -CHO, -COCl, -NH ₂ , -SO ₂ Cl, -COOH, -COOR ', -Cl, -Br, -I, -COOCOR' and

Is any one selected from the group consisting of wherein R 'is a straight or branched chain alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 8 carbon atoms or an aralkyl group having 6 to 8 carbon atoms Wherein the alkyl group is unsubstituted or substituted with 1 to 41 fluorine atoms, the aryl group is unsubstituted or substituted with 1 to 9 fluorine atoms, and the aralkyl group is unsubstituted or substituted with 1 to 9 fluorine atoms .

As described above, the cellulose acetate used in the present invention includes one acetate group and two hydroxy groups per repeating unit, and since the hydroxy group is reactive among these groups, various compounds may be bound to the cellulose acetate using the same.

In the present invention, in particular, a compound containing fluorine, that is, a compound containing a reactor capable of reacting with the above-mentioned hydroxyl group as a fluorine compound, is reacted with the cellulose acetate to obtain fluorinated acetate.

Any fluorine compound including a reactor capable of reacting with a hydroxyl group may be used as the fluorine compound of the present invention. Preferably, the fluorine compound represented by Chemical Formula 1 may be used.

Further, preferably, the fluorine compound represented by Chemical Formula 1 may be CF ₃ COOH (trifluoroacetic acid), (CF ₃ CO) ₂ O (trifluoroacetic anhydride trifluoroacetic anhydride), CF ₃ CN (trifluoro Acetonitrile trifluoroacetonitrile), CF ₃ COCl (trifluoroacetyl chloride), CF ₃ C ₂ H ₂ O (trifluoroepoxypropane trifluoroepoxypropane), CF ₃ CH ₂ OH (trifluoroethanol trifluoroethanol), CF ₃ CF ₂ CHFOH (hexafluoropropanol hexafluoropropanol), C ₆ F ₅ NH ₂ (pentafluoroaniline pentafluoroaniline), C ₆ F ₅ CHO (pentafluorobenzaldehyde pentafluorobenzaldehyde), C ₆ F ₅ SO ₂ Cl (pentafluorobenzenesulphate Pentafluorobenzenesulfonyl chloride), C ₆ F ₅ CO ₂ H (pentafluorobenzoic acid), C ₆ F ₅ CH ₂ OH (pentafluorobenzyl alcohol), C ₆ F ₅ CH ₂ Br ( Pentafluorobenzyl bromide, CF ₃ CF ₂ I (pentafluoroiodoethane), ICH ₂ (CF ₂ ) ₃ CHF ₂ (octafluoroiodopentane octafluoroiodopentane), F ₂ CH (CF ₂ ) ₃ CH ₂ OH (octafluoropentanol octafluoropentanol), heptadecafluoroundecyliodide and any one selected from the group consisting of a mixture thereof, More preferably, the fluorine compound represented by the formula (1) CF ₃ CF ₂ CHFOH (hexafluoropropanol hexafluoropropanol) or heptadecafluoroundecyliodide.

The method for producing a piezoelectric paper of the present invention, using the fluorinated cellulose acetate obtained by the above-described method for producing fluorinated cellulose acetate, comprises polling, stretching, or polling and stretching the fluorinated cellulose acetate described above; Or polling, stretching or polling and stretching and deacetylating.

The polling process may be performed by various methods such as corona polling, grid polling, contact polling, and the like, and the given voltage is 0.5 depending on the state of the sample, that is, the fluorinated cellulose acetate. It can be achieved by adding kV to 25 kV.

The stretching treatment may be performed by stretching the fluorinated cellulose acetate thin film by 1.1 to 2.5 times by simply pulling mechanically, and this mechanical stretching may be performed while warming to a temperature of 60 to 150 ℃, water, alcohol, chloroform A fluorinated cellulose acetate thin film may be immersed therein using a solvent such as a halogenated hydrocarbon such as halogenated hydrocarbon. This stretching treatment may also be performed simultaneously with the deacetylation reaction described below.

In the fluorine compound represented by Formula 1, when R is a lower (1-8 carbon atoms) alkyl group, an aryl group, and an aralkyl group, only the polling treatment or the polling and stretching treatment are performed, and in the case of the higher alkyl group, the stretching treatment is performed. Can only be performed. In the case where R is a higher alkyl group, both polling and stretching can be performed.

When the cellulose fibers and fluorine-containing functional groups of the fluorinated cellulose acetate are arranged in a certain direction by the polling and / or stretching treatment, the piezoelectric charge constant is greatly increased due to the strong electronegativity of the fluorine.

The deacetylation reaction may be carried out by a general deacetylation reaction.

For example, in the deacetylation reaction, deacetylation occurs when sodium alkoxide roll is dissolved in alcohol and the fluorinated cellulose acetate thin film is soaked.

By this deacetylation reaction, the acetate group in the repeating unit of the fluorinated cellulose acetate of the present invention is deacetylated so that the fluorinated cellulose acetate becomes fluorinated cellulose.

Medical piezoelectric paper, piezoelectric paper for RFID (Radio-Frequency IDentification), motor, power generation equipment, speaker, etc. can be manufactured using the piezoelectric paper obtained by the method of manufacturing the piezoelectric paper of the present invention as described above. It can be applied to various fields where paper can be used.

Hereinafter, the present invention will be described in detail by way of examples, but these examples are only directed to more clearly understand the present invention, and are not intended to limit the scope of the present invention. It will be determined within the scope of the technical spirit of the claims.

[ Example ]

Comparative Example 1 Piezoelectric Paper Made in the Prior Art (following the piezoelectric paper manufacturing method according to Korean Patent Publication No. 10-2009-87280)

To the bulk cellulose is added a solvent of sodium hydroxide, DMAX (N, M-Dimethylaccetamid) or NMMO (N-methylmorpholine-N-oxide) to form a cellulose solution. Thereafter, the container is subjected to spin coating, extrusion, or casting to form a thin film in which cellulose fibers are arranged in a predetermined direction. The formed thin film is washed with water to remove the remaining solvent, and the electrode is installed on the formed cellulose thin film.

Comparative example  2: cellulose acetate

Cellulose acetate (CA, molecular weight 30,000, 39.8% acetate) was purchased from Sigma Aldrich.

Example : Reaction of cellulose acetate with fluorine compound

Misunobu  reaction( Mitsunobu reaction ) (- OH /- OH  reaction)

Example 1 Cellulose acetate (CA, molecular weight 30,000, 39.8% acetate), triphenylphosphine (TPP), tetrahydrofurane (THF), 1,1,1,3, 3,3, -hexafluoro-2-propanol (1,1,1,3,3,3-hexafluo-2-propanol) (HFP), diethyl azodicarboxylate (DEAD in toluene 40 wt%) was purchased from Sigma Aldrich.

CA (100 mg), TPP (720 mg), HFP (0.15 ml) and DEAD (0.42 ml) were dissolved in anhydrous THF (15 ml). The mixture of solutions was stirred at ambient temperature for 27 hours and 93 hours, respectively, under a nitrogen atmosphere. At this time, in order to minimize the content of water in the reaction, anhydrous THF was used as a solvent, and reacted under dry nitrogen conditions. The reaction was poured into 150 ml of methanol. The precipitate was obtained by filtration and the unreacted starting material and byproducts were removed by repeated washing with methanol and water. The precipitate was dissolved in THF and spin coated at 1,000 rpm using a spin coater. X-ray diffraction patterns and FTIR spectra were recorded using a Nicol-6700 spectrometer and a wide angle X-ray diffractometer. In addition, thermogravimetric analysis and differential thermogravimetric analysis were performed using STA 409 PC / NETZSCH, the analysis was performed under nitrogen and the samples were heated at a rate of 10 ° C./min. Morphology and EDX of the powder samples were recorded using a scanning electron microscope (Hitachi S-4200).

1 is a reaction scheme showing a reaction for producing fluorinated cellulose acetate by reacting cellulose acetate with a fluorine compound according to Example 1 in a misobu portion.

2 to 9 below, "CA" indicates cellulose acetate of Comparative Example 2, "27 hours" (hereinafter referred to as "CA-HFP27") and "93 hours". (Hereinafter referred to as "CA-HFP93" in the description) are both fluorinated cellulose acetate prepared according to Example 1 of the present invention, the former is a solution of a solution of CA, TPP, HFP and DEAD dissolved in anhydrous THF The mixture is obtained by stirring at ambient temperature for 27 hours under nitrogen atmosphere, the latter being obtained by stirring at ambient temperature for 93 hours.

2 is the FTIR spectra for CA and CA-HFP27 and CA-HFP93.

According to this FIG. 2, for CA, sharp and strong absorption peaks at 1050, 1300, 1400, and 1730 cm ⁻¹ are shown. A broad absorption peak centered at 3400 cm ⁻¹ indicates characteristic absorption by the —OH group. Fluorine compounds show sharp absorption peaks at 690, 730, 850 and 900 cm ⁻¹ , with strong and strong absorption peaks at 1100 to 1400 cm ⁻¹ and 3100 to 3700 cm ⁻¹ . Absorption intensity by CA at 2800 to 3000 cm ⁻¹ showing -CH, -CH ₂ and -CH ₃ stretching vibrations is relatively weak. Sharp new FTIR absorption peaks of CA-HFP27 and CA-HFP93 appear at 600, 800 and 900 cm ⁻¹ . From 1000 to 1400 cm ^{- 1,} and the absorption peak at 2800 to 3000 cm ^-1 it was sharply increased. Absorption intensity of CA-HFP93 at 800 cm ⁻¹ and 2800 to 3000 cm ⁻¹ , indicating CF banding vibration, was weaker than absorption strength of CA-HFP27. It can be seen from this that a small amount of fluorine compound can assist in stretching and bending vibrations of the product of Example 1 of the present invention due to the strong electronegativity of fluorine.

These results clearly show the presence of fluorine compounds in CA-HFP27 and CA-HFP93, ie, the product of Example 1 of the present invention.

Figure 3 shows the XRD pattern for the cellulose acetate of Comparative Example 2 and the fluorinated cellulose acetate prepared according to Example 1 of the present invention.

According to this FIG. 3, the maximum diffraction peaks of CA and CA-HFP27 and CA-HFP93 are 2θ = 20.27 °, 20.31 ° and 22.61 °, respectively. The maximum diffraction peak of CA-HFP27 is slightly shifted to a higher angle compared to CA, while the maximum rotational peak of CA-HFP93 is shifted sharply to a higher angle. This may be due to the presence of hydrogen bonds with F-H-O and F-H-C, which changes the stacking pattern of the cellulose acetate film.

4 and 5 show the results of thermogravimetric analysis and differential thermogravimetric analysis for CA, CA-HFP27 and CA-HFP-93, respectively.

According to this FIG. 4, CA slowly decomposes at 260 ° C. and begins to decompose rapidly at 320 ° C. FIG.

5, CA, CA-HFP27 and CA-HFP93 show peaks at 359.2, 359.0 and 364.2 ° C, respectively, with CA-HFP27 degrading earlier than CA. This may be due to the contribution of intermolecular or intramolecular hydrogen bonds. The longer the reaction time, the more fluorine compounds are attached to the cellulose acetate chain and form strong intermolecular or intramolecular hydrogen bonds due to the strong electronegativity of the fluorine. Therefore, CA-HFP93 shows higher thermal stability than CA and CA-HFP27. CA-HFP27 shows a second decomposition peak at about 500 ° C. These results show that CA-HFP27 has intermediate physical and chemical properties between CA and CA-HFP93.

6 and 7 are scanning electron microscope images of CA-HFP27 and CA-HFP93, and FIGS. 8 and 9 show EDX patterns (fluorine content analysis results) for CA-HFP27 and CA-HFP93.

6 and 7, the CA has a porous morphology while the hexafluoro propyl portion has a smooth morphology. 8 and 9, CA-HFP27 and CA-HFP93 show fluorine contents of 9.2 wt% and 16.7 wt%, respectively.

Example 2 : Cellulose acetate (CA, 39.8% acetate), triphenylphosphine (TPP), tetrahydrofurane (THF), hexafluopropanol (HFP), Diethyl azodicarboxylate (DEAD 40 wt% in toluene) was purchased from Sigma Aldrich.

CA (100 mg) and TPP (150 mg) were dissolved in THF (40 ml) at room temperature. And made under nitrogen conditions. HFP (0.1 ml) and DEAD (0.1 ml) were added thereto and reacted at room temperature for 7 days. After the reaction, the mixture was washed repeatedly with methanol and water. As a result, an amount of fluorine of 4 wt% was observed in cellulose acetate. The fluorine content was analyzed by energy dispersive spectroscopy (EDS) and electron spectroscopy for chemical analysis (ESCA, x-ray photoemission spectroscopy (XPS)).

Misunobu  reaction( Mitsunobu Reaction ) (- OH /- OH  reaction)

Example 3 : Cellulose acetate (CA, 39.8% acetate), triphenylphosphine (TPP), tetrahydrofurane (THF), hexafluopropanol (HFP), Diethyl azodicarboxylate (40 wt% DEAD in toluene) was purchased from Sigma Aldrich.

CA (100 mg) and TPP (900 mg) were dissolved in THF at room temperature. And it made a nitrogen atmosphere. HFP (0.6 ml) and DEAD (0.6 ml) were added thereto and reacted at room temperature for 7 days. After the reaction, the mixture was washed repeatedly with methanol and water. As a result, an amount of fluorine of 16 wt% was observed in cellulose acetate. The fluorine content was analyzed by energy dispersive spectroscopy (EDS) and electron spectroscopy for chemical analysis (ESCA, x-ray photoemission spectroscopy (XPS)).

William  Ether synthesis ( Williams ether synthesis ) (- ONa /- OH  reaction)

Example 4 CA (335 mg) was dissolved in dimethylacetamide (DMAc, 40 ml). Sodium (20 mg) was added at room temperature. Then 4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,11-heptadecafluoroundecyliodide (Sinma-Aldrich, 80 mg) Put it. This reaction was allowed to stand at room temperature for 24 hours. After the reaction, the mixture was washed with methanol.

Polymerization (- COOH /- OH  reaction)

Example 5 : CA (300 mg) was dissolved in 50 ml of THF. The temperature was maintained at 60 ℃ and carbondiimidazole (Sigma-Aldrich, 100 mg) was added to maintain the same temperature for 24 hours. Then trifluoacetic acid (Sigma-Aldrich, TFA, 5 ml) was added. Stir for 24 hours while maintaining the temperature. The reaction was washed with methanol.

In Examples 6 to 19, the starting material was replaced with the fluorine compounds of Table 1 and reacted in a similar manner to Examples 1 to 5 to obtain fluorinated cellulose acetate.

Example
Starting material
Example 6
Trifluoroacetic anhydride
Example 7
Trifluoroacetonitrile
Example 8
Trifluoroacetyl chloride
Example 9
Tripleolo Epoxy Propane
Example 10
Trifluoroethanol
Example 11
Pentafluoroaniline
Example 12
Pentafluorobenzaldehyde
Example 13
Pentafluorobenzenesulfonyl chloride
Example 14
Pentafluorobenzoic acid
Example 15
Pentafluorobenzyl alcohol
Example 16
Brominated Pentafluorobenzyl
Example 17
Pentafluoroiodineethane
Example 18
Octafluoroiodopentane
Example 19
Octafluoropentanol

The present invention has been described above with reference to the illustrated examples, but this is only an example and the present invention can perform various modifications and other equivalent embodiments that are obvious to those skilled in the art. Understand the facts. For example, a method of synthesizing polymers using radicals using monomers having groups such as various celluloses, acrylates, methacrylates, vinyls, and heat or photoinitiators is also possible.

Claims (16)

Fluorinated cellulose acetate obtained by reacting cellulose acetate with a fluorine compound represented by Formula 1 below:
[Formula 1]
RX
Where
R is a straight or branched chain alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 8 carbon atoms or an aralkyl group having 6 to 8 carbon atoms, wherein the alkyl group is selected from 1 to 41 fluorine atoms Substituted, the aryl group is substituted with 1 to 9 fluorine atoms, and the aralkyl group is substituted with 1 to 9 fluorine atoms; And
X is -OH, -CN, -CHO, -COCl, -NH ₂ , -SO ₂ Cl, -COOH, -COOR ', -Cl, -Br, -I, -COOCOR' and

Is any one selected from the group consisting of wherein R 'is a straight or branched chain alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 8 carbon atoms or an aralkyl group having 6 to 8 carbon atoms Wherein the alkyl group is unsubstituted or substituted with 1 to 41 fluorine atoms, the aryl group is unsubstituted or substituted with 1 to 9 fluorine atoms, and the aralkyl group is unsubstituted or substituted with 1 to 9 fluorine atoms . According to claim 1, wherein the fluorine compound represented by Formula 1 is CF ₃ COOH (trifluoroacetic acid trifluoroacetic acid), (CF ₃ CO) ₂ O (trifluoroacetic anhydride trifluoroacetic anhydride), CF ₃ CN (trifluor Loacetonitrile trifluoroacetonitrile), CF ₃ COCl (trifluoroacetyl chloride), CF ₃ C ₂ H ₂ O (trifluoroepoxypropane trifluoroepoxypropane), CF ₃ CH ₂ OH (trifluoroethanol trifluoroethanol), CF ₃ CF ₂ CHFOH (hexafluoropropanol hexafluoropropanol), C ₆ F ₅ NH ₂ (pentafluoroaniline pentafluoroaniline), C ₆ F ₅ CHO (pentafluorobenzaldehyde pentafluorobenzaldehyde), C ₆ F ₅ SO ₂ Cl (pentafluorobenzene chloride _{pentafluorobenzenesulfonyl chloride), C 6 F 5} CO 2 H ( acid pentafluorobenzoic acid), pentafluorophenyl C ₆ F ₅ CH ₂ OH (benzyl alcohol pentafluorophenyl _{pentafluorobenzyl alcohol), C 6 F 5} CH 2 Br ( probe Chemistry benzyl pentafluorobenzyl bromide) _{pentafluorophenyl, CF 3 CF 2 I (,} ICH 2 iodine ethane pentafluoroiodoethane) pentafluorophenyl (CF _{2) 3} CHF ₂ (a octafluoro-iodo-pentane _{octafluoroiodopentane), F 2 CH (CF} 2) 3 Fluorinated cellulose acetate, which is selected from the group consisting of CH ₂ OH (octafluoropentanol), heptadecafluoroundecyliodide, and mixtures thereof. The fluorinated cellulose acetate of claim 1, wherein the fluorine compound represented by Chemical Formula 1 is CF ₃ CF ₂ CHFOH (hexafluoropropanol hexafluoropropanol) or heptadecafluoroundecyliodide. Polling, stretching, or polling and stretching the fluorinated cellulose acetate of any one of claims 1 to 3; Or piezoelectric paper obtained by polling, stretching or polling and stretching and deacetylation. The piezoelectric paper according to claim 4, wherein the piezoelectric charge constant (d31) of the piezoelectric paper is 50 pC / N or more. The piezoelectric paper according to claim 4, wherein the piezoelectric charge constant (d31) of the piezoelectric paper is 100 pC / N or more. The piezoelectric paper according to claim 4, wherein the piezoelectric charge constant (d31) of the piezoelectric paper is 150 pC / N or more. A method for producing fluorinated cellulose acetate comprising the step of reacting cellulose acetate with a fluorine compound represented by the following formula (1).
[Formula 1]
RX
Where
R is a straight or branched chain alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 8 carbon atoms or an aralkyl group having 6 to 8 carbon atoms, wherein the alkyl group is selected from 1 to 41 fluorine atoms Substituted, the aryl group is substituted with 1 to 9 fluorine atoms, and the aralkyl group is substituted with 1 to 9 fluorine atoms; And
X is -OH, -CN, -CHO, -COCl, -NH ₂ , -SO ₂ Cl, -COOH, -COOR ', -Cl, -Br, -I, -COOCOR' and

Is any one selected from the group consisting of wherein R 'is a straight or branched chain alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 8 carbon atoms or an aralkyl group having 6 to 8 carbon atoms Wherein the alkyl group is unsubstituted or substituted with 1 to 41 fluorine atoms, the aryl group is unsubstituted or substituted with 1 to 9 fluorine atoms, and the aralkyl group is unsubstituted or substituted with 1 to 9 fluorine atoms . According to claim 8, wherein the fluorine compound represented by Formula 1 is CF ₃ COOH (trifluoroacetic acid trifluoroacetic acid), (CF ₃ CO) ₂ O (trifluoroacetic anhydride trifluoroacetic anhydride), CF ₃ CN (trifluoro Loacetonitrile trifluoroacetonitrile), CF ₃ COCl (trifluoroacetyl chloride), CF ₃ C ₂ H ₂ O (trifluoroepoxypropane trifluoroepoxypropane), CF ₃ CH ₂ OH (trifluoroethanol trifluoroethanol), CF ₃ CF ₂ CHFOH (hexafluoropropanol hexafluoropropanol), C ₆ F ₅ NH ₂ (pentafluoroaniline pentafluoroaniline), C ₆ F ₅ CHO (pentafluorobenzaldehyde pentafluorobenzaldehyde), C ₆ F ₅ SO ₂ Cl (pentafluorobenzene chloride _{pentafluorobenzenesulfonyl chloride), C 6 F 5} CO 2 H ( acid pentafluorobenzoic acid), pentafluorophenyl C ₆ F ₅ CH ₂ OH (benzyl alcohol pentafluorophenyl _{pentafluorobenzyl alcohol), C 6 F 5} CH 2 Br ( probe Chemistry benzyl pentafluorobenzyl bromide) _{pentafluorophenyl, CF 3 CF 2 I (,} ICH 2 iodine ethane pentafluoroiodoethane) pentafluorophenyl (CF _{2) 3} CHF ₂ (a octafluoro-iodo-pentane _{octafluoroiodopentane), F 2 CH (CF} 2) 3 CH ₂ OH (octafluoropentanol octafluoropentanol), heptadecafluoroundecyliodide, and a mixture thereof. The method of producing fluorinated cellulose acetate. The method of claim 8, wherein the fluorine compound represented by Formula 1 is CF ₃ CF ₂ CHFOH (hexafluoropropanol hexafluoropropanol) or heptadecafluoroundecyliodide, the production of fluorinated cellulose acetate Way. Polling, stretching, or polling and stretching the fluorinated cellulose acetate obtained by the process of any one of claims 8 to 10; Or polling, stretching or polling and stretching and deacetylating. Medical pulse sensor comprising the piezoelectric paper of claim 4. A piezoelectric paper for RFID (Radio-Frequency IDentification) comprising the piezoelectric paper of claim 4 and an electrode coupled to the piezoelectric paper. A motor comprising the piezoelectric paper of claim 4. A power plant comprising the piezoelectric paper of claim 4. A speaker comprising the piezoelectric paper of claim 4.

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