WO2017213419A1 - Color transformation photonic crystal structure, color transformation photonic crystal sensor using same, and counterfeit petroleum detecting photosensor using same - Google Patents

Abstract

The present invention relates to a photonic crystal structure and a counterfeit petroleum detecting photosensor comprising the same. The photosensor has excellent sensitivity and reproductivity and exhibits a fast response time, and the same enables detection of counterfeit petroleum by the naked eye and can be reused repeatedly.

Description

Color conversion photonic crystal structure, color conversion photonic crystal sensor and optical sensor for quasi oil detection

The present invention relates to a color conversion photonic crystal structure, a color conversion photonic crystal sensor using the same, and an optical sensor for detecting similar oil.

A photonic crystal is a structure in which dielectric materials having different refractive indices are arranged periodically, and superimposed interference occurs between light scattered at regular regular grid points to selectively transmit light in a specific wavelength range. Refers to a material that reflects light, that is, forms an optical band gap.

Such photonic crystals use photons instead of electrons as a means of information processing, and thus, the speed of information processing is excellent and is emerging as a key material for improving the efficiency of the information industry. Furthermore, the photonic crystal can be implemented as a one-dimensional structure in which photons move in the principal axis direction, a two-dimensional structure in which the photons move along a plane, or a three-dimensional structure in which the photons move freely in all directions throughout the material. It is easy to control the optical characteristics and can be applied to various fields. For example, photonic crystals may be applied to optical devices such as photonic crystal fibers, light emitting devices, photovoltaic devices, photonic crystal sensors, semiconductor lasers, and the like.

In particular, the Bragg stack is a photonic crystal having a one-dimensional structure, and can be easily manufactured by only stacking two layers having different refractive indices, and controlling the optical properties by controlling the refractive index and thickness of the two layers is easy. There is this. Due to these features, the Bragg stack is widely used for applications as photonic crystal sensors that detect electrical, chemical, and thermal stimuli as well as energy devices such as solar cells. Accordingly, studies have been made on various materials and structures for easily manufacturing a photonic crystal sensor excellent in sensitivity and reproducibility.

Accordingly, the present inventors have made intensive efforts, and as described below, the repeating unit derived from the acrylate or acrylamide monomer having a repeating unit derived from a fluoroalkyl acrylate monomer and a photoactive functional group in one repeating layer of the Bragg stack. When using a copolymer containing at the same time, it was confirmed that it is possible to easily produce a color conversion photonic crystal structure that changes color according to the type and concentration change of the organic solvent and a photonic crystal sensor showing excellent sensitivity accordingly, the present invention Completed.

The present invention is to provide a color conversion photonic crystal structure sensitive to an organic solvent.

The present invention also provides a color conversion photonic crystal sensor having excellent sensitivity and reproducibility using the color conversion photonic crystal structure and exhibiting a fast response time.

In addition, the present invention is to provide an optical sensor for detecting similar petroleum, which can be repeatedly reused with excellent sensitivity and reproducibility, including a photonic crystal structure which is converted into color upon contact with similar petroleum.

In addition, the present invention is to provide a method for detecting similar petroleum using the optical sensor.

In order to solve the above problems, the present invention is a first refractive index layer comprising a first polymer exhibiting a first refractive index, alternately stacked; And a second refractive index layer including a second polymer exhibiting a second refractive index, wherein the first refractive index and the second refractive index are different, and one of the first polymer and the second polymer is represented by the following Chemical Formula 1 It provides a color conversion photonic crystal structure which is a copolymer represented by:

[Formula 1]

In Chemical Formula 1,

R ₁ and R ₂ are each independently hydrogen or C _1-3 alkyl,

X ₁ is C _1-10 fluoroalkyl,

L ₁ is O or NH,

Y ₁ is benzoylphenyl,

Wherein Y ₁ is unsubstituted or substituted with 1 to 4 substituents each independently selected from the group consisting of hydroxy, halogen, nitro, C _1-5 alkyl and C _1-5 alkoxy,

n and m are each independently an integer of 1 or more,

n + m is 100-1,000.

The present invention also provides a color conversion photonic crystal sensor comprising the photonic crystal structure.

In addition, the present invention provides an optical sensor for detecting similar petroleum including the photonic crystal structure.

In addition, the present invention comprises the step of contacting the optical sensor with a sample and the optical

It provides a pseudo petroleum detection method comprising the step of detecting the pseudo petroleum in the sample through color conversion of the photonic crystal structure of the sensor.

The color conversion photonic crystal structure of the present invention comprises a low refractive index layer using a copolymer comprising a repeating unit derived from a fluoroalkyl acrylate monomer and a repeating unit derived from an acrylate or acrylamide monomer having a photoactive functional group. Including, the color can be converted to be visually determined according to the type and concentration change of the organic solvent, the photonic crystal sensor using the color conversion photonic crystal structure can exhibit a fast response time with excellent sensitivity and reproducibility have.

The optical sensor of the present invention uses a photonic crystal structure in which color is converted upon contact with pseudo petroleum, so that the detection of pseudo petroleum can be performed with the naked eye and can be easily used, while having excellent sensitivity and reproducibility and being reusable repeatedly. There is a characteristic.

FIG. 1 schematically illustrates a structure of a color conversion photonic crystal structure according to an embodiment.

2 to 4 show the 1 H-NMR spectra of the copolymers prepared in Production Examples 2 to 4, respectively.

5 shows the results of thermogravimetric analysis of the copolymers prepared in Production Examples 2 to 4 and Comparative Production Example 1. FIG.

6 to 9 show optical photographs of contact angles with respect to water on the surfaces of the photonic crystal structures prepared in Examples 1 to 3 and Comparative Example 1, respectively.

10 shows the specular reflectance before and after the thermal shock test of the photonic crystal structures prepared in Examples 1 to 3 and Comparative Example 1. FIG.

11 to 13 show color conversion photographs (a) and specular reflectances (b) of benzene, toluene, xylene, ethanol and methanol of the photonic crystal structures prepared in Examples 1, 4 and 5, respectively.

14 to 18 show specular reflection according to changes in the concentration of benzene in the photonic crystal structures prepared in Examples 4 and 6 to 9, respectively.

19A to 19C show reproducibility test results for benzene, toluene and xylene of the photonic crystal structure prepared in Example 1, respectively.

20 shows the response time test results for benzene, toluene, xylene, ethanol and methanol of the photonic crystal structure prepared in Example 1. FIG.

FIG. 21 shows color conversion photographs (a) and specular reflectances (b) of genuine gasoline, thinner, methanol, and toluene of the photonic crystal structure prepared in Example 5. FIG.

FIG. 22 shows color conversion photographs (a) and specular reflectances (b) of benzene, toluene, xylene, ethanol, and methanol of the photonic crystal structure prepared in Example 5. FIG.

FIG. 23 shows color conversion photographs (a) and specular reflectances (b) of pseudo-petrol mixed with genuine gasoline and toluene in various ratios of the photonic crystal structure prepared in Example 5. FIG.

FIG. 24 shows color conversion photographs (a) and specular reflectances (b) of pseudo-petrol in which genuine gasoline and methanol of the photonic crystal structure prepared in Example 5 are mixed at various ratios.

FIG. 25 is a color conversion photograph (a) and a specular reflectance (b) of a pseudo gasoline in which the thinner, toluene and methanol of the photonic crystal structure prepared in Example 5 are mixed at various ratios.

Hereinafter, the present invention will be described in more detail. The terms or words used in this specification and claims are not to be construed as limiting in their usual or dictionary meanings, and the inventors may appropriately define the concept of terms in order to best explain their invention in the best way possible. It should be interpreted as meaning and concept corresponding to the technical idea of the present invention based on the principle that the present invention.

In addition, the meaning of “comprising” as used in the specification of the present invention embodies a particular characteristic, region, integer, step, operation, element and / or component, and other characteristics, region, integer, step, operation, element and / or It does not exclude the presence or addition of ingredients.

Some of the terms used in the following specification may be defined as follows.

First, the term 'color conversion photonic crystal structure' used in the present invention is a Bragg stack having a one-dimensional photonic crystal structure manufactured by repeatedly stacking materials having different refractive indices, and having a specific wavelength due to a periodic difference in refractive index of the stacked structures. The light may reflect light in an area, and the reflected wavelength refers to a structure shifted by an external stimulus to convert a reflected color. Specifically, partial reflection of light occurs at the boundary of each layer of the structure, and many of these reflected waves can structurally interfere to reflect light of a specific wavelength having high intensity. At this time, the shift of the reflection wavelength due to the external stimulus occurs as the wavelength of the scattered light changes as the lattice structure of the material forming the layer is changed by the external stimulus. Such a color conversion photonic crystal structure may be manufactured in the form of a coating film coated on a separate substrate or a substrate, or in the form of a free standing film, and includes an optical device such as a photonic crystal fiber, a light emitting device, a photovoltaic device, a photonic crystal sensor, a semiconductor laser, and the like. It can be applied to. For example, the color conversion photonic crystal structure may be used in biosensors such as optical sensors, glucose sensors, protein sensors, DNA sensors, disease diagnosis sensors, portable diagnostic sensors, and the like, such as environmental elements for chemical and species detection. The application is not limited.

On the other hand, the color conversion photonic crystal structure of the present invention, the first refractive index layer comprising a first polymer exhibiting a first refractive index, alternately stacked; And a second refractive index layer comprising a second polymer exhibiting a second refractive index, wherein the first refractive index and the second refractive index are different.

Accordingly, the first refractive index layer may be a high refractive index layer, the second refractive index layer may be a low refractive index layer, or alternatively, the first refractive index layer may be a low refractive index layer, and the second refractive index layer may be a high refractive index layer.

Low refractive index layer

The term 'low refractive index layer' used in the present invention means a layer having a relatively low refractive index among two kinds of layers included in the photonic crystal structure. In this case, as one of the first polymer and the second polymer, the polymer included in the low refractive index layer is a copolymer represented by the following formula (1):

[Formula 1]

In Chemical Formula 1,

R ₁ and R ₂ are each independently hydrogen or C _1-3 alkyl,

X ₁ is C _1-10 fluoroalkyl,

L ₁ is O (oxygen) or NH,

Y ₁ is benzoylphenyl,

Wherein Y ₁ is unsubstituted or substituted with 1 to 4 substituents each independently selected from the group consisting of hydroxy, halogen, nitro, C _1-5 alkyl and C _1-5 alkoxy,

n and m are each independently an integer of 1 or more,

n + m is 100-1,000.

The copolymer represented by the formula (1) is an acrylate (L1 = O) or acrylamide having a repeating unit derived from a fluoroalkyl (X1) acrylate monomer and a photo-active functional group (Y1) L ₁ = NH) refers to a polymer including a repeating unit derived from a monomer at the same time.

When the copolymer represented by Formula 1 includes a repeating unit derived from a fluoroalkyl (X1) acrylate monomer, the refractive index is lower than that of the polymer not containing the repeating unit, and thermal stability, chemical resistance, and oxidation Excellent chemical properties such as stability and excellent transparency. Here, 'fluoroalkyl' refers to a functional group in which one or more fluorine atoms are substituted for the hydrogen atom of alkyl, wherein one or more fluorine atoms may be substituted for the hydrogen atom of the side chain as well as the terminal of C1-10 alkyl, Two or more fluorine atoms may be all bonded to one carbon atom, or each may be bonded to two or more carbon atoms.

In addition, as the number of fluorine atoms in the copolymer represented by Chemical Formula 1 increases, the refractive index becomes lower and the hydrophobicity may increase, thereby controlling the difference in refractive index between the high refractive index layer and the low refractive index layer according to the number of fluorine atoms. Color conversion photonic crystal structure having a reflection wavelength can be implemented.

Furthermore, the copolymer represented by Chemical Formula 1 further includes repeating units derived from an acrylate or acrylamide-based monomer having a photoactive functional group (Y ₁ ), so that photocuring itself is performed without a separate photoinitiator or crosslinker. It may be possible.

The copolymer represented by Chemical Formula 1 is prepared by random copolymerization of an acrylate or acrylamide monomer having a fluoroalkyl (X ₁ ) acrylate monomer and a photoactive functional group (Y ₁ ). The repeating units between the brackets may be random copolymers arranged randomly from each other.

Alternatively, the copolymer represented by Formula 1 may be a block copolymer in which blocks of repeating units between square brackets of Formula 1 are connected by covalent bonds. Also, alternatively, it may be an alternating copolymer in which the repeating units between the brackets of Formula 1 are arranged alternately, or may be a graft copolymer in which any one of the repeating units is combined in a branched form. The form is not limited.

The copolymer represented by Formula 1 may exhibit a refractive index of 1.3 to 1.5. In the above-described range, a photonic crystal structure reflecting light having a desired wavelength may be implemented by a difference in refractive index with a polymer used in the high refractive index layer described later.

In Formula 1, R ₁ and R ₂ may be each independently hydrogen or methyl. For example, R ₁ and R ₂ can be hydrogen.

In addition, in Chemical Formula 1, X ₁ may be C _1-5 fluoroalkyl.

For example, X ₁ is fluoromethyl, difluoromethyl, trifluoromethyl, 1-fluoroethyl, 2-fluoroethyl, 1,1-difluoroethyl, 1,2-difluoroethyl , 2,2-difluoroethyl, 1,1,2-trifluoroethyl, 1,2,2-trifluoroethyl, 2,2,2-trifluoroethyl, 1-fluoropropyl, 2 -Fluoropropyl, 1,1-difluoropropyl, 1,2-difluoropropyl, 2,2-difluoropropyl, 1,1,2-trifluoropropyl, 1,2,2-tri Fluoropropyl, 2,2,2-trifluoropropyl, 1-fluorobutyl, 2-fluorobutyl, 1,1-difluorobutyl, 1,2-difluorobutyl, 2,2-di Fluorobutyl, 1,1,2-trifluorobutyl, 1,2,2-trifluorobutyl or 2,2,2-trifluorobutyl.

In addition, in Chemical Formula 1, Y ₁ may be benzoylphenyl unsubstituted or substituted with C _1-3 alkyl. When Y ₁ is benzoylphenyl, it may be advantageous in view of ease of photocuring.

In addition, in Formula 1, n means the total number of repeating units derived from fluoroalkyl acrylate-based monomers in the copolymer, m is an acrylate or acryl having a photoactive functional group (Y ₁ ) in the copolymer The total number of repeat units derived from amide monomers.

In this case, the copolymer represented by Chemical Formula 1 may have a molar ratio of n: m of 100: 1 to 100: 10 and a number average molecular weight of 10,000 to 100,000 g / mol. For example, the copolymer represented by Formula 1 may have a molar ratio of n: m of 100: 1 to 100: 5, specifically 100: 1 to 100: 2. In addition, for example, the copolymer represented by Chemical Formula 1 may have a number average molecular weight of 20,000 to 80,000 g / mol, specifically 20,000 to 60,000 g / mol. Within this range, it is possible to produce a copolymer having a low refractive index and easy photocuring.

Specifically, the copolymer represented by Chemical Formula 1 may be one of the copolymers represented by the following Chemical Formulas 1-1 to 1-3:

[Formula 1-1]

[Formula 1-2]

[Formula 1-3]

In Formulas 1-1 to 1-3, the definitions of n and m are as defined above.

High refractive index layer

The term 'high refractive index layer' used in the present invention means a layer having a relatively high refractive index among two kinds of layers included in the photonic crystal structure. The polymer included in the high refractive index layer is not the copolymer represented by Chemical Formula 1, but is another one of the first polymer and the second polymer, and includes a structural unit derived from the following monomer, It can exhibit a high refractive index compared to the copolymer represented: (meth) acrylate type compound, (meth) acrylamide type compound, vinyl group containing aromatic compound, dicarboxylic acid, xylylene, alkylene oxide, arylene Oxides, and derivatives thereof. These can be applied individually or in mixture of 2 or more types.

For example, the polymer included in the high refractive index layer may include one or two or more structural units derived from the following monomers: methyl (meth) acrylate, ethyl (meth) acrylate, isobutyl ( Metha) acrylate, 1-phenylethyl (meth) acrylate, 2-phenylethyl (meth) acrylate, 1,2-diphenylethyl (meth) acrylate, phenyl (meth) acrylate, benzyl (meth) acrylic (Meth) acrylate type monomers, such as a rate, m-nitrobenzyl (meth) acrylate, (beta) -naphthyl (meth) acrylate, and benzoylphenyl (meth) acrylate; Methyl (meth) acrylamide, ethyl (meth) acrylamide, isobutyl (meth) acrylamide, 1-phenylethyl (meth) acrylamide, 2-phenylethyl (meth) acrylamide, phenyl (meth) acrylamide, benzyl (Meth) acrylamide monomers, such as (meth) acrylamide and benzoylphenyl (meth) acrylamide; Styrene monomers such as styrene, o-methyl styrene, m-methyl styrene, p-methyl styrene, p-methoxy styrene, o-methoxy styrene, and 4-methoxy-2-methyl styrene; aromatic monomers such as p-divinylbenzene, 2-vinylnaphthalene, vinylcarbazole and vinylfluorene; Terephthalic acid, isophthalic acid, 2,6-naphthalene dicarboxylic acid, 2,7-naphthalene dicarboxylic acid, 1,4-naphthalene dicarboxylic acid, 1,4-phenylene dioxyphenylene acid, 1,3-phenylene dioxydiacetic acid, etc. Dicarboxylic acid monomers; xylylene-based monomers such as o-xylene, m-xylene and p-xylene; Alkylene oxide monomers such as ethylene oxide and propylene oxide; Phenylene oxide type monomers, such as phenylene oxide and 2, 6- dimethyl- 1, 4- phenylene oxide. Among them, it is preferable to have structural units derived from styrene-based monomers and structural units derived from one of (meth) acrylate and (meth) acrylamide in view of implementing a desirable refractive index difference and ease of photocuring.

Specifically, other than the copolymer represented by Formula 1, the other of the first polymer and the second polymer may be a copolymer represented by the following formula (2):

[Formula 2]

In Chemical Formula 2,

R ₃ and R ₄ are each independently hydrogen or C _1-3 alkyl,

R ₁₁ is hydroxy, cyano, nitro, and _{amino, SO 3 H, SO 3 (} C 1- 5 alkyl), C _1-10 alkyl or C _1-10 alkoxy,

a1 is an integer of 0 to 5,

L ₂ is O or NH,

Y ₂ is benzoylphenyl,

Wherein Y ₂ is unsubstituted or substituted with 1 to 4 substituents each independently selected from the group consisting of hydroxy, halogen, nitro, C _1-5 alkyl and C _1-5 alkoxy,

n 'and m' are each independently an integer of 1 or more,

n '+ m' is from 100 to 1,000.

The copolymer represented by the formula ( ₂ ) is a repeat derived from an acrylate (L ₂ = O) or acrylamide (L ₂ = NH) monomer having a structural unit and a photoactive functional group (Y ₂ ) derived from a styrene monomer It may mean a polymer including a unit at the same time.

When the copolymer represented by Formula 2 includes a repeating unit derived from a styrene monomer, a high refractive index is higher than that of the copolymer including the repeating unit derived from the fluoroalkyl (X ₁ ) acrylate monomer. Implementation of the layer is possible.

Furthermore, the copolymer represented by Chemical Formula 2 may further include a repeating unit derived from an acrylate or acrylamide monomer having a photoactive functional group (Y ₂ ), and may be photocurable by itself without a separate photoinitiator or crosslinking agent. .

The copolymer represented by the formula ( ₂ ) is a random copolymer of the styrene monomer and the acrylate or acrylamide monomer having a photoactive functional group (Y ₂ ), the repeating units between the square brackets of the formula (2) are random from each other It may be a random copolymer arranged so as to.

Alternatively, the copolymer represented by Formula 2 may be a block copolymer in which blocks of repeating units between square brackets of Formula 2 are connected by covalent bonds. In addition, alternatively, it may be an alternating copolymer in which the repeating units between the brackets of Formula 2 are arranged alternately, or may be a graft copolymer in which any one of the repeating units is combined in a branched form, but the arrangement of the repeating units The form is not limited.

The copolymer represented by Formula 2 may exhibit a refractive index of 1.51 to 1.8. When in the above-described range, a photonic crystal structure reflecting light of a desired wavelength may be implemented by a difference in refractive index with the polymer represented by Chemical Formula 1.

In Formula 2, R ₃ and R ₄ may be each independently hydrogen or methyl. For example, R ₃ and R ₄ may be hydrogen.

In addition, in Formula 2, R ₁₁ may be methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, or tert-butyl. In this case, a1 means the number of R ₁₁ , and may be 0, 1, or 2.

In addition, in Chemical Formula 2, Y ₂ may be unsubstituted or benzoylphenyl substituted with C _1-3 alkyl. When Y ₂ is benzoyl, phenyl, which is advantageous in terms of ease of photocuring.

In addition, in Formula 2, n 'means the total number of repeating units derived from fluoroalkyl acrylate-based monomers in the copolymer, m' is an acrylate or acrylamide-based having a photoactive functional group in the copolymer The total number of repeat units derived from monomers.

In this case, the copolymer represented by Formula 2 has a molar ratio of n ': m' of 100: 1 to 100: 20, for example, 100: 1 to 100: 10, and for example, 100: 1 to 100: 5. Can be. In addition, the copolymer represented by Formula 2 may have a number average molecular weight (Mn) of 10,000 to 300,000 g / mol, for example, 50,000 to 180,000 g / mol. In the above range, it is possible to prepare a copolymer represented by the formula (1) and the copolymer easy to cure photo having a refractive index difference of the above-described range.

The polymer represented by Formula 2 described above may swell upon contact with compounds that may be included as pseudopetroleum. This is because, as the compound represented by the formula (2) includes repeating units derived from styrene monomers, the swelling behavior is increased due to higher solubility in thinners, aromatic compounds, and alcohol compounds than the compound represented by the formula (1). That is, the color conversion of the photonic crystal structure may be caused by shifting the reflection wavelength of the photonic crystal structure due to swelling of the polymer represented by the formula (2).

Color conversion Photonic crystal  Structure

The color conversion photonic crystal structure according to the present invention includes a first refractive index layer disposed on a lowermost portion, a second refractive index layer disposed on the first refractive index layer, and a first refractive index layer alternately stacked on the second refractive index layer. And a structure of the second refractive index layer.

In addition, the color conversion photonic crystal structure may further include a substrate on the other surface of the first refractive index layer of the first refractive index layer disposed on the lowermost part according to the use. Therefore, in this case, the substrate may be positioned at the bottom of the color conversion photonic crystal structure.

Hereinafter, a schematic structure of the color conversion photonic crystal structure 10 according to an embodiment of the present invention will be described with reference to FIG. 1.

Referring to FIG. 1, a color conversion photonic crystal structure 10 according to an embodiment may include a substrate 11 and a first refractive index layer 13 and a second refractive index layer 15 alternately stacked on the substrate 11. It consists of

In this case, the first refractive index layer 13 may be positioned on the top of the color conversion photonic crystal structure. Accordingly, the first refractive index layer 13 is further laminated on the laminate in which the first refractive index layer 13 and the second refractive index layer 15 are alternately stacked, so that the photonic crystal structure includes an odd refractive index layer. Can have. In this case, constructive interference between the lights reflected at the interface of each layer is increased, as described later, so that the intensity of the reflection wavelength of the photonic crystal structure can be increased.

The substrate 11 is a carbon-based material, metal foil, thin glass, silicon (Si), plastic, polyethylene (PE), polyethylene having excellent mechanical strength, thermal stability, transparency, surface smoothness, ease of handling and waterproofing It may be a polymer film such as terephthalate (PET), polypropylene (PP), paper, skin, clothing, or a wearable material, but is not limited thereto, and various materials that are flexible or not flexible depending on the intended application. Can be used.

The first refractive index layer 13, which is alternately stacked on the substrate 11, includes a first polymer exhibiting a first refractive index n1, and the second refractive index layer 15 has a second refractive index n2. It includes a second polymer that represents. In this case, a difference between the first refractive index n1 and the second refractive index n2 may be 0.01 to 0.5. For example, the difference between the first refractive index n1 and the second refractive index n2 may be 0.05 to 0.3, specifically 0.1 to 0.2. As the difference between the refractive indices increases, the optical band gap of the photonic crystal structure increases, so that the light having a desired wavelength may be reflected by adjusting the difference between the refractive indices within the above-described range.

For example, the first refractive index n1 may be 1.51 to 1.8, and the second refractive index n2 may be 1.3 to 1.5. In other words, the first refractive index layer 13 is a high refractive index layer, and the second refractive index layer 15 corresponds to a low refractive index layer, so that the photonic crystal structure 10 is disposed on the substrate 11. The low refractive index layer / high refractive index layer / low refractive index layer / high refractive index layer may have a structure stacked sequentially.

Alternatively, the first refractive index n1 may be 1.3 to 1.5, and the second refractive index n2 may be 1.51 to 1.8. In other words, the first refractive index layer 13 is a low refractive index layer, and the second refractive index layer 15 corresponds to a high refractive index layer, so that the photonic crystal structure 10 is formed on the substrate 11. The high refractive index layer / low refractive index layer / high refractive index layer / low refractive index layer may have a structure that is sequentially stacked.

In addition, the thickness of the low refractive index layer may be greater than or equal to the thickness of the high refractive index layer. For example, the ratio of the thickness of the low refractive index layer to the thickness of the high refractive index layer may be 1: 1.1 to 1: 0.3. Specifically, the thickness of the low refractive index layer is 30 to 100nm, the thickness of the high refractive index layer may be 20 to 70 nm. By adjusting the thickness in the above-described range, it is possible to adjust the reflection wavelength of the photonic crystal structure. The thickness of each refractive index layer can be adjusted by varying the concentration of the polymer in the polymer dispersion composition or the coating speed of the dispersion composition.

In FIG. 1, only the photonic crystal structure 10 having a total of five layers is illustrated, but the total number of stacked layers of the photonic crystal structure is not limited thereto. Specifically, the total number of stacked layers of the first refractive index layer and the second refractive index layer may be 5 to 30 layers. In the case of the structures stacked in the above-described range, the interference of the reflected light at each layer boundary surface is sufficiently generated to have a reflection intensity such that a change in color due to an external stimulus is detected.

On the other hand, when the multi-colored white light of all colors in equal proportion is incident on the color conversion photonic crystal structure 10, partial reflection of incident light occurs at each layer boundary surface, and one wavelength is caused by the interference of the partially reflected light. It can represent the color according to the reflected wavelength (λ).

Specifically, the reflection wavelength λ of the color conversion photonic crystal structure 10 may be determined by Equation 1 below:

[Equation 1]

λ = 2 (n1 * d1 + n2 * d2)

Wherein n1 and n2 are the refractive indices of the first and second refractive index layers 13 and 15, respectively, and d1 and d2 are the refractive indices of the first and second refractive index layers 13 and 15, respectively. Means thickness. Accordingly, the desired reflection wavelength λ may be realized by adjusting the types of the first and second polymers and the thicknesses of the first refractive index layer 13 and the second refractive index layer 15.

When there is no external stimulus, the color conversion photonic crystal structure 10 exhibits a reflection wavelength λ corresponding to a visible light region of 200 to 760 nm according to Equation 1 to confirm the reflection color by the photonic crystal structure. Can be.

When the color conversion photonic crystal structure 10 is positioned in an environment subject to external stimulation, the crystal lattice of the first polymer and the second polymer constituting the first refractive index layer 13 and the second refractive index layer 15, respectively As the structure is changed, the photonic crystal structure 10 reflects the shifted wavelength [lambda] 'as the shape scattered at each layer boundary is changed. Therefore, the color implemented by the photonic crystal structure can be converted as compared with the case where there is no external stimulus. If the intensity of the external stimulus is high, since the degree of change of the crystal lattice structure of the first polymer and the second polymer is increased and the reflection wavelength is further shifted, the intensity of the external stimulus can be detected according to the color to be implemented.

For example, the shift of the reflection wavelength of the photonic crystal structure 10 may be due to swelling of the first polymer and / or the second polymer by external stimulation. In particular, the reflection wavelength λ ′ shifted by the external stimulus may correspond to a visible light region that can be perceived by the human eye. For example, the reflection wavelength λ ′ shifted by the external stimulus may be in the range of 380 nm to 760 nm. The reflection wavelength [lambda] and the shifted reflection wavelength [lambda] 'can be measured by a device such as a reflectometer.

Here, the external stimulus may be a chemical stimulus, for example, a stimulus caused by a change in concentration of a chemical. Specifically, the external stimulus may be due to a change in concentration of the organic solvent. For example, the organic solvent may be an aromatic organic solvent or an organic solvent such as ethyl acetate (EA), tetrahydrofuran (THF), dimethylformamide (DMF), ethyl lactate, cyclohexanone, methylene chloride, methylethylketone (MEK), and the like. It may be a solvent. In particular, it is possible to respond with high sensitivity to external stimuli caused by a change in concentration of an aromatic organic solvent such as benzene, xylene, toluene and the like. In this case, the polymer included in the high refractive index layer of the photonic crystal structure may respond to the change in concentration of the aromatic organic solvent, and more specifically, the polymer represented by Formula 2 may be sensitive. That is, the shift of the reflection wavelength of the color conversion photonic crystal structure according to the embodiment according to the external stimulus may be due to the swelling of the polymer represented by the formula (2).

In addition, the degree of shift of the reflection wavelength of the structure may vary depending on the type of the organic solvent, and thus may exhibit different colors, because of the swelling behavior of the first polymer and / or the second polymer according to the type of the solvent. ) Is different. Specifically, the swelling behavior of the polymer with respect to the solvent can be determined by the solubility parameter (δ), and Hansen solubility parameter is mainly used as the solubility parameter (δ).

Specifically, Hansen solubility parameters for benzene, xylene and toluene are shown in Table 1 below.

In Table 1, δ _t is Total hidebrand, δ _d is a dispersion component, δ _P is a polar component, δ _dP is (δ _dP = (δ ² _d + δ ² _P) ) ^1/2 ), and δ _h means a hydrogen bonding component.

For example, the degree of swelling of the first polymer and / or the second polymer may be influenced by the dispersible component parameter (δ _d ) of the solubility parameter, specifically, as the value of the dispersible component parameter increases The degree of swelling of the polymer and / or the second polymer may be increased.

As shown in Table 1 above, swelling of the first polymer and / or the second polymer, as xylene, toluene and benzene have dispersible component parameter values of 17.8, 18.1 and 18.4 (cal / ml) ^½ respectively The degree is increased in the order of xylene, toluene and benzene. Therefore, even in the same photonic crystal structure, since its reflection wavelength is shifted toward the longer wavelength in the order of xylene, toluene and benzene, detection of each solvent can be facilitated accordingly.

In addition, the shift degree of the reflection wavelength λ ′ of the color conversion photonic crystal structure may vary depending on the intensity of the external stimulus. In detail, when the intensity of the external stimulus increases, for example, as the concentration of the organic solvent increases, the reflection wavelength of the photonic crystal structure may increase. Therefore, the concentration of the organic solvent as well as the type of the organic solvent can be detected using the color conversion photonic crystal structure.

The color conversion photonic crystal structure as described above may be manufactured by a manufacturing method comprising the following steps:

1) preparing a first refractive index layer using a first dispersion composition comprising a first polymer exhibiting a first refractive index;

2) preparing a second index of refraction layer on the first index of refraction layer using a second dispersion composition comprising a second polymer exhibiting a second index of refraction; And

3) alternately stacking the first refractive index layer and the second refractive index layer to produce a photonic crystal structure in which 5 to 30 layers are stacked.

In the method of manufacturing the color conversion photonic crystal structure, description of the first refractive index, the first polymer, the second refractive index, the second polymer, the first refractive index layer, and the second refractive index layer is as described above.

First, a first dispersion composition and a second dispersion composition are prepared. Each dispersion composition can be prepared by dispersing a polymer in a solvent, where the dispersion composition is used as a term indicating various states such as solution phase, slurry phase or paste phase. In this case, the solvent may be used as long as it can dissolve the first and second polymers, and the first and second polymers may be included in an amount of 0.5 to 5 wt% based on the total weight of the dispersion composition. In the above-described range, a dispersion composition having a viscosity suitable for being applied onto a substrate can be prepared.

For example, the first dispersion composition may consist of a solvent and a first polymer, and the second dispersion composition may consist of a solvent and a second polymer. In other words, the photocuring agent may not include a separate photoinitiator and a crosslinking agent or inorganic particles. Therefore, the photonic crystal structure can be manufactured more easily and economically, and the dispersion of the optical properties according to the position of the prepared photonic crystal structure can be reduced by not including a separate additive.

Next, after applying the prepared first dispersion composition on a substrate or substrate to perform a light irradiation to prepare a first refractive index layer, and then after applying the prepared second dispersion composition on the first refractive index layer Irradiation may be performed to prepare a second refractive index layer.

Here, spin coating, dip coating, roll coating, screen coating, spray coating, or the like may be applied by applying the dispersion composition onto a substrate or a refractive index layer. Spin casting, flow coating, screen printing, ink jet, drop casting, or the like may be used, but is not limited thereto.

The light irradiation step may be performed by irradiation with 365 nm wavelength under nitrogen conditions. The photocured refractive index layer may be prepared by acting as a photoinitiator of the benzophenone moiety contained in the polymer by the light irradiation.

Color conversion Photonic crystal  sensor

On the other hand, according to another embodiment of the present invention, a color conversion photonic crystal sensor including the color conversion photonic crystal structure described above is provided.

The color conversion photonic crystal sensor may be used for detecting an organic solvent as the reflection wavelength of the photonic crystal structure is shifted according to the change of the organic solvent concentration.

Furthermore, the color conversion photonic crystal sensor can detect not only the presence of the organic solvent as the detection material but also the concentration, and thus can be used for both qualitative and quantitative analysis of the detection material. In addition, the color conversion photonic crystal sensor is not only the color conversion due to the external stimulus is clear, it can be quickly restored to the original state when the external stimulus is stopped, it can be used repeatedly.

Light sensor for quasi oil detection

On the other hand, the petroleum-like petroleum on the market includes a compound such as thinner, an aromatic organic solvent, or an alcoholic organic solvent as described above. At this time, examples of the aromatic organic solvent include benzene, toluene or xylene, and examples of the alcoholic organic solvent include methanol, ethanol, isopropanol, isobutanol and the like. Therefore, for the detection of pseudo petroleum, a sensor capable of rapidly reacting with the compound is required. In addition, such a detection sensor is preferably portable and can be reused repeatedly so that anyone can easily use.

The optical sensor for detecting similar petroleum of the present invention includes a photonic crystal structure in which the color is converted upon contact with the similar petroleum, so that the presence of the similar petroleum in the sample may be visually confirmed. In this case, the photonic crystal structure includes a first refractive index layer including a first polymer exhibiting a first refractive index, alternately stacked, and a second refractive index layer including a second polymer exhibiting a second refractive index different from the first refractive index. do.

The reflection wavelength of such a photonic crystal structure is such that when the photonic crystal structure comes into contact with compounds that may be included as pseudopetroleum, the reflection wavelength of the structure is caused by swelling of the first polymer and / or the second polymer included in the photonic crystal structure. Will be shifted. This is because when the first polymer and / or the second polymer are swollen, the crystal lattice structure of each refractive index layer is changed to change the shape of light scattered at each layer boundary.

That is, the photonic crystal structure shows the converted color by the shifted reflection wavelength λ ', and it is possible to confirm the presence of pseudo petroleum by the color conversion of the photonic crystal structure.

In particular, when the reflection wavelength λ and the shifted reflection wavelength λ 'of the photonic crystal structure are within the range of 380 nm to 760 nm, which is the visible light region, color conversion of the photonic crystal structure can be easily confirmed with the naked eye.

In addition, the photonic crystal structure may have a different color due to the shift of the reflection wavelength depending on the type of the compound, and the reason may be different colors because of the swelling behavior of the first polymer and / or the second polymer depending on the type of the solvent. behavior is different. Accordingly, by using the optical sensor including the photonic crystal structure, it is possible not only to confirm the presence of pseudopetroleum, but also to check the components of the compound constituting the pseudopetroleum.

In this case, when the pseudo petroleum includes an aromatic organic solvent, the swelling behavior of the first polymer and / or the second polymer may be determined by the solubility parameter (d).

Specifically, the swelling behavior of the first polymer and / or the second polymer is influenced by the dispersible component parameter dd, so that the degree of swelling of the first polymer and / or the second polymer increases as the value of the dispersible component parameter increases. As a result, the shifted degree of the reflection wavelength of the photonic crystal structure is increased. Thus, as shown in Table 1, the swelling of the first polymer and / or the second polymer, as xylene, toluene and benzene have dispersible component parameter values of 17.8, 18.1 and 18.4 (cal / ml) ^½ respectively The degree is increased in the order of xylene, toluene and benzene. Accordingly, the reflection wavelength of the photonic crystal structure may also be shifted in order of xylene, toluene, and benzene in order of long wavelength, for example, to change the color represented by the photonic crystal structure, and thus, it may be possible to identify a component of the compound constituting the pseudopetroleum.

On the other hand, when the petroleum-like organic solvent is included in the petroleum-like swelling behavior of the first polymer and / or the second polymer may be determined by hydrogen bonding with the alcohol-based organic solvent. Specifically, the first polymer and / or the second polymer may be swollen by hydrogen bonding between the hydroxy group in the alcoholic organic solvent and the acrylate or acrylamide having the benzoylphenyl group included in the first polymer and / or the second polymer. Can be.

Accordingly, the thickness and refractive index of the first refractive index layer and / or the second refractive index layer including the same may be changed, so that color conversion of the photonic crystal structure may occur.

On the other hand, the optical sensor may be provided with a detection unit including the above-described photonic crystal structure that can be converted to the color when contacted with the petroleum similar oil to determine the presence of petroleum and a fixing portion for fixing it.

Since the photonic crystal structure can be manufactured in various sizes and shapes by taking the form of a thin film, the optical sensor having the same may be manufactured in various sizes and shapes depending on the intended use.

In addition, the optical sensor may further include a reference unit that exemplifies a color converted according to a kind of a compound which may be included as genuine petroleum and similar petroleum for reference. Through the color illustrated in the reference unit, it is possible to check whether or not the genuine petroleum and the kind of the compound included in the sample.

The optical sensor may visually detect pseudo petroleum through color conversion of the photonic crystal structure when the pseudo petroleum in the sample contains about 10% (V / V) or more. In this case, when measuring the specular reflectance of the photonic crystal structure of the optical sensor, it is possible to detect pseudo petroleum until the content of pseudo petroleum in the sample is ppm.

In addition, the optical sensor can determine whether or not a similar petroleum is present in the sample even if a small amount of the sample as long as the amount of sample can penetrate into the photonic crystal structure.

In addition, the optical sensor may exhibit a response time within about 2 minutes. Therefore, it is possible to immediately check whether or not a similar petroleum at the site of gasoline or diesel using the optical sensor.

Moreover, the optical sensor can be used repeatedly and continuously. In detail, the photonic crystal structure in the optical sensor may be repeatedly reused after a predetermined time since the photonic crystal structure is restored to the original color. Therefore, it can be environmentally friendly and economical compared to the sensor that must be discarded after one use.

Pseudo-oil detection method

On the other hand, according to another embodiment of the present invention, there is provided a method for detecting similar petroleum using the optical sensor for detecting similar petroleum.

The quasi-petroleum detection method includes the following steps:

1) contacting the above-described optical sensor with a sample; And

2) detecting pseudo petroleum in the sample through color conversion of the photonic crystal structure of the optical sensor.

The contact between the optical sensor and the sample in step 1) is sufficient to allow the sample to get wet inside the photonic crystal structure in the optical sensor. Thus, similar petroleum detection may be possible with only a small amount of sample. In addition, the color conversion in step 2) can be clearly seen within a short time, as can be seen in the embodiments described later.

Hereinafter, preferred examples are provided to aid in understanding the present invention.

However, the following examples are merely provided to more easily understand the present invention, and the contents of the present invention are not limited by the following examples.

Material used

The following materials were used in the following Preparation and Comparative Preparation Examples. At this time, each material was used without a separate purification process.

4-aminobenzophenone: TCI (Tokyo chemical industry) with 98% purity

Product was used.

Triethylamine: A product of 99% purity TCI (Tokyo Chemical Industry) was used.

-Dichloromethane: Purity 99.9% Burdick & Jackson product was used.

Acryloyl chloride: Merck company of purity 96% was used.

Tetrahydrofuran: A Burdick & jackson product having a purity of 99.99% was used.

p-methylstyrene: Sigma-aldrich from 96% purity was used.

Azobisisobutyronitrile: Purified by JUNSEI from 98% purity.

1,4-dioxane: Sigma-aldrich manufactured at 99% purity was used.

N-isopropyl acrylamide: TCI (Tokyo Chemical Industry) company of purity 98% was used.

2,2,2-trifluoroethylacrylate: A product of TCI (Tokyo Chemical Industry) having a purity of 98% was used.

Monomers and Copolymer  Mark

The names and notations of the monomers and copolymers prepared in the following Preparation Examples and Comparative Preparation Examples are shown in Table 2 below.

[Correction under Article 91 of the Rule 09.08.2017]

(Monomer synthesis)

Production Example  A: Of BPAA  Produce

9.96 g of 4-aminobenzophenone, 7 mL of triethylamine, 80 mL of dichloromethane were placed in a 250 mL round flask and the flask was placed in ice water.

4.06 mL of acryloyl chloride was diluted in 8 mL of dichloromethane and slowly dropped dropwise into the flask, followed by stirring for 12 hours. After completion of the reaction, the unreacted materials and salts were removed with a 5% NaHCO 3 and saturated aqueous sodium chloride solution using a separatory funnel. Drying in a vacuum oven gave the title compound as a yellow solid.

Production Example  B: Of FEA  Produce

30 mL of acryloyl chloride (37.5 mmol), 52 ml of triethylamine (37.5 mmol) and 200 mL of tetrahydrofuran were placed in a One-neck round flask and the flask was placed in ice water. 18.3 mL of 2-fluoroethanol (31.2 mmol) was diluted in 30 mL of tetrahydrofuran and slowly stirred dropwise into the flask. When the diluted solution enters, the mixture was stirred at room temperature for 12 hours. After completion of the reaction, the precipitate was filtered and the remaining solution was concentrated using a rotary evaporator. The concentrated sample was columned with hexane: ethyl acetate (1: 3) to separate only the material, and then the solvent was removed using a rotary evaporator to obtain the title compound.

Production Example  C: DFEA  Produce

224 mL of acryloyl chloride (29.3 mmol), 40.8 ml of triethylamine (29.3 mmol) and 200 mL of tetrahydrofuran were placed in a one-neck round flask and the flask was placed in ice water. 15.4 mL of 2,2-difluoroethanol (24.4 mmol) was diluted in 30 mL of tetrahydrofuran, and then slowly added dropwise into the flask and stirred. When the diluted solution enters, the mixture was stirred at room temperature for 12 hours.

After completion of the reaction, the precipitate was filtered and the remaining solution was concentrated using a rotary evaporator. The concentrated sample was columned with hexane: ethyl acetate (1: 3) to separate only the material, and then the solvent was removed using a rotary evaporator to obtain the title compound.

( Copolymer  synthesis)

Production Example  One: Of Poly (p-MS-BPAA)  Produce

3 ml of p-methylstyrene, 0.451 g of BPAA prepared in Preparation Example A, 0.0046 g of azobisisobutyronitrile (0.0913 mmol), and 30 mL of 1,4-dioxane were placed in a 25 ml Schrank round flask. Put and then stirred. After freeze-pump-thaw was blown three times for 20 minutes with nitrogen, the flask was placed in an 80 degree oil bath for 15 hours. After the completion of the reaction, the precipitate was caught with methanol, filtered, the polymer was extracted, and dried in a vacuum oven at room temperature to obtain Poly (p-MS-BPAA) (n '= 250, m' = 9).

Production Example  2: Of Poly (FEA-BPAA)  Produce

1.64 g of FEA (1.38 mmol) prepared in Preparation Example B, 0.0351 g of BPAA (0.14 mmol) prepared in Preparation Example A, 0.0046 g of azobisisobutyronitrile (0.028 mmol), 6 mL of 1 , 4-Dioxane was placed in a 25 ml Schrank round flask and stirred. After freeze-pump-thaw was blown three times for 20 minutes with nitrogen, the flask was placed in an 80 degree oil bath for 15 hours. After the completion of the reaction, the precipitate was caught with ethanol, filtered and the polymer was extracted, and dried in a vacuum oven at room temperature to obtain Poly (FEA-BPAA) (n = 495, m = 5).

Production Example  3: Of Poly (DFEA-BPAA)  Produce

1.89 g of DFEA (1.38 mmol) prepared in Preparation Example C, 0.0351 g of BPAA (0.14 mmol) prepared in Preparation Example A, 0.0046 g of azobisisobutyronitrile (0.028 mmol), 6 mL of 1 , 4-Dioxane was placed in a 25 ml Schrank round flask and stirred. After freeze-pump-thaw was blown three times for 20 minutes with nitrogen, the flask was placed in an 80 degree oil bath for 15 hours. After completion of the reaction, the precipitate was caught with ethanol, filtered and the polymer was extracted and dried in a vacuum oven at room temperature to obtain Poly (DFEA-BPAA) (n = 495, m = 9).

Production Example  4: Of Poly (TFEA-BPAA)  Produce

25 ml of 1.75 mL of TFEA (1.38 mmol), 0.0351 g of BPAA (0.14 mmol) prepared in Preparation A, 0.0046 g of azobisisobutyronitrile (0.028 mmol), 8 mL of 1,4-dioxane Was put into a Schlenk round flask, followed by stirring. After freeze-pump-thaw was blown three times for 20 minutes with nitrogen, the flask was placed in an 80 degree oil bath for 15 hours. After the completion of the reaction, the precipitate was caught with ethanol, filtered and the polymer was extracted, and dried in a vacuum oven at room temperature to obtain Poly (TFEA-BPAA) (n = 495, m = 7).

Comparative Production Example  One: Of Poly (NIPAM-BPAA)  Produce

1.57 g of N-isopropyl acrylamide (1.38 mmol), 0.0351 g of BPAA (0.14 mmol) prepared in Preparation Example 1 above, 0.0046 g of azobisisobutyronitrile (0.028 mmol), 6 mL of 1,4 Dioxane was placed in a 25 ml Schrank round flask and stirred. After freeze-pump-thaw was blown three times for 20 minutes with nitrogen, the flask was placed in an 80 degree oil bath for 15 hours. After the completion of the reaction, the precipitate was caught with cooled ethyl ether, filtered, the polymer was extracted, and dried in a vacuum oven at room temperature to obtain Poly (NIPAM-BPAA) (n = 495, m = 6).

Experimental Example  One: Copolymer  Property measurement

Specific physical properties of the copolymers prepared in Preparation Examples 1 to 4 and Comparative Preparation Example 1 were measured by the following method. The results are shown in Table 3, and 1H-NMR spectra of the copolymers of Preparation Examples 2 to 4 are shown in FIGS. 2 to 4, respectively.

1) Mn (number average molecular weight): Polymethyl methacrylate was measured using gel permeation chromatography (GPC) as a standard sample for calibration.

2) Tg (glass transition temperature): Measured using a differential scanning calorimeter (DSC).

3) Content of BPAA structural unit: measured by NMR.

4) Refractive index: It measured by ellipsometer.

Experimental Example  2: Copolymer Heat weight  analysis

Thermogravimetric analysis (TGA) was performed on each of the copolymers prepared in Preparation Examples 2 to 4 and Comparative Preparation Example 1, and the results are shown in FIG. 5.

As shown in FIG. 5, the copolymers prepared in Preparation Examples 2 to 4 had weight loss from about 350 ° C. or higher, whereas the copolymers prepared in Comparative Preparation Example 1 had weight loss as soon as the temperature started to rise. It can be seen. As a result, it can be seen that the thermal stability of the copolymer prepared in Preparation Example is excellent.

( Color conversion Photonic crystal  Manufacture of structures)

Example  One

The high refractive index dispersion composition was prepared by dissolving Poly (p-MS-BPAA) prepared in Preparation Example 1 to 1 wt% in toluene, and preparing Poly (FEA-BPAA) prepared in Preparation Example 2 in ethyl acetate. It was dissolved to wt% to prepare a low refractive index dispersion composition.

The low refractive index dispersion composition was coated on a glass substrate using a spin coater at 2,000 rpm for 50 seconds and then cured at 365 nm for 5 minutes to prepare a low refractive index layer having a thickness of 71.6 nm. The glass substrate on which the low refractive index layer was formed was placed in an ethyl acetate solution to remove the uncured portion.

Next, the high refractive index dispersion composition was applied on the low refractive index layer for 50 seconds at 2,000 rpm using a spin coater, and then cured for 5 minutes at 365 nm to prepare a high refractive index layer having a thickness of 33.8 nm. The glass substrate in which the said low refractive index layer and the high refractive index layer were formed was put into the toluene solution, and the part which is not hardened was removed.

Thereafter, the low refractive index layer and the high refractive index layer were repeatedly stacked on the high refractive index layer to prepare a photonic crystal structure in which a total of 15 refractive index layers were stacked.

Example  2

The low refractive index dispersion composition was prepared by dissolving Poly (DFEA-BPAA) prepared in Preparation Example 3 to 2wt% in ethyl acetate, and applying the low refractive index dispersion composition at 2,000 rpm for 5 minutes at 365 nm under nitrogen. Except for curing, a photonic crystal structure in which a total of 15 layers of 65.7 nm thick low refractive index layer and 33.8 nm thick high refractive index layer were repeatedly stacked on a glass substrate was used in the same manner as in Example 1.

Example  3

The poly (TFEA-BPAA) prepared in Preparation Example 4 was dissolved in ethyl acetate to 2wt%, and the low refractive index dispersion composition was cured using nitrogen in the same manner as in Example 1 except curing for 20 minutes at 365 nm under nitrogen. A photonic crystal structure in which a total of 15 layers of a low refractive index layer having a thickness of 32.8 nm and a high refractive index layer having a thickness of 33.8 nm was repeatedly stacked on the substrate was manufactured.

Example  4

The high refractive index dispersion composition was prepared by dissolving Poly (p-MS-BPAA) prepared in Preparation Example 1 to 1.2 wt% in toluene, except that the low refractive index dispersion composition was applied at 1,900 rpm. Using the same method, a photonic crystal structure in which a total of 15 layers of a low refractive index layer having a thickness of 72.5 nm and a high refractive index layer having a thickness of 55.6 nm were repeatedly stacked on a glass substrate was prepared.

Example  5

The high refractive index dispersion composition was prepared by dissolving Poly (p-MS-BPAA) prepared in Preparation Example 1 to 1.2 wt% in toluene, except that the low refractive index dispersion composition was applied at 1,700 rpm. Using the same method, a photonic crystal structure in which a total of 15 layers of a 76.8 nm thick low refractive index layer and a 58.8 nm thick high refractive index layer were repeatedly stacked on a glass substrate was used.

Example  6

The high refractive index dispersion composition was prepared by dissolving Poly (p-MS-BPAA) prepared in Preparation Example 2 to 1.2 wt% in toluene, except that the low refractive index dispersion composition was applied at 1,500 rpm. Using the same method, a photonic crystal structure in which a total of 15 layers of 85.1 nm thick low refractive index layer and 63.2 nm thick high refractive index layer were repeatedly stacked on a glass substrate was prepared.

Example  7

Using the same method as Example 6, a photonic crystal structure in which a total of 195.1 layers of a low refractive index layer having a thickness of 85.1 nm and a high refractive index layer having a thickness of 63.2 nm were repeatedly stacked on a glass substrate was prepared.

Example  8

Using the same method as in Example 6, a photonic crystal structure in which a total of 25 layers of a low refractive index layer having a thickness of 85.1 nm and a high refractive index layer having a thickness of 63.2 nm were repeatedly stacked on a glass substrate was prepared.

Example  9

The high refractive index dispersion composition was prepared by dissolving Poly (p-MS-BPAA) prepared in Preparation Example 1 to 1 wt% in toluene, and preparing Poly (FEA-BPAA) prepared in Preparation Example 2 in ethyl acetate. It was dissolved to wt% to prepare a low refractive index dispersion composition.

Next, a silicon wafer was used as the substrate, and the low refractive index dispersion composition and the high refractive index dispersion composition were applied on the silicon wafer substrate using the same method as in Example 1, except that 50 seconds were applied at 2,000 rpm for 50 seconds. A photonic crystal structure in which 15 nm-thick low refractive index layers and 39.6 nm-thick high refractive index layers were repeatedly stacked in total was prepared.

Comparative example  One

67.1 was prepared on the glass substrate using the same method as in Example 1, except that the low refractive index dispersion composition was prepared by dissolving Poly (NIPAM-BPAA) prepared in Comparative Preparation Example 1 to 2 wt% in 1-propanol. A photonic crystal structure in which 15 nm-thick low refractive index layers and 39.6 nm-thick high refractive index layers were repeatedly stacked in total was prepared.

The photonic crystal structures prepared in Examples and Comparative Examples are summarized in Table 4 below.

Experimental Example  3: Photonic crystal  Struct Contact angle  Measure

For the surfaces of the photonic crystal structures prepared in Examples 1 to 3 and Comparative Example 1, the contact angle with respect to water was measured using a contact angle meter (PHOENIX product name, manufactured by Surface Electro Optic). At this time, 3.2 μl of water droplets were used, and the measured contact angle data means an average value of five repeated measurements. The results and the optical photographs are shown in Table 5 and FIGS. 6 to 9, respectively.

As shown in Table 5 and Figures 6 to 9, when the fluoroalkyl acrylate is used as the copolymer of the low refractive index layer, compared to the case of using Poly (NIPAM-BPAA), the surface of the photonic crystal structure by fluorine It can be seen that it represents hydrophobicity. In addition, it can be seen that as the content of fluorine in the copolymer of the low refractive index layer increases, the contact angle with respect to water increases to increase the hydrophobicity.

Experimental Example  4: Photonic crystal  Struct Thermal shock  exam

Prior to the thermal shock test, specular reflectances of the photonic crystal structures prepared in Examples 1 to 3 and Comparative Example 1 were measured using a reflectometer (USB 4000, Ocean Optics).

Thereafter, a thermal shock test (Thermal Shock test) was repeated using a thermal shock test chamber (manufactured by Espec Corporation) for 50 cycles of leaving the photonic crystal structures at -20 ° C for 30 minutes and at 100 ° C for 30 minutes. Afterwards, specular reflectances of the photonic crystal structures were re-measured using a reflectometer (USB 4000, Ocean Optics).

The specular reflectance measurement results before and after the thermal shock test are shown in FIG. 10.

As shown in FIG. 10, the photonic crystal structure of Comparative Example 1 using Poly (NIPAM-BPAA) as the low refractive index layer polymer before the thermal shock test showed low specular reflectance of about 10% over a wide wavelength range, The photonic crystal structure of 2 can exhibit high specular reflectance in a narrow wavelength range. Therefore, by using a photonic crystal structure including a copolymer containing a repeating unit derived from a fluoroalkyl acrylate monomer, a photonic crystal sensor can be easily identified by visually shifting the color conversion due to a clear shift in reflection wavelength due to an external stimulus. It was confirmed that it can be prepared.

Further, the photonic crystal structures of Examples 1 and 2 have almost no change in the reflected wavelength even after the thermal shock test, and thus the optical crystal structures having excellent heat resistance can be manufactured using the photonic crystal structures.

Experimental Example  5: according to the change of solvent Color conversion  observe

In order to confirm the degree of color conversion according to the solvent, the photonic crystal structure prepared in Example 1 was soaked in benzene, toluene, xylene, ethanol and methanol until there was no color change, and the changed color was observed. The photo is shown in Fig. 11A. In addition, the specular reflectance of the photonic crystal structure prepared in Example 1 according to the solvent change was measured using a reflectometer (USB 4000, Ocean Optics), and the results are shown in FIG. 11B. In this case, "pristine" means the color of the photonic crystal structure before immersion in the solvent.

As shown in Figures 11a and 11b, it can be seen that the reflection wavelength of the photonic crystal structure prepared in Example 1 is changed according to the type of solvent, the color represented is different. In particular, when the photonic crystal structure is exposed to aromatic organic solvents such as benzene, toluene, and xylene, the change of the reflection wavelength is larger than that of the initial structure, so that a visible color change can be observed with the naked eye. Specifically, the photonic crystal structure has a large degree of shift of the reflection wavelength in the order of ethanol, methanol, xylene, toluene and benzene.

This means that as described above, the values of the solubility parameters in the order of xylene, toluene and benzene increased, so that the degree of swelling of the polymer in the photonic crystal structure prepared in the above example increased in this order. Therefore, the optical sensor including the photonic crystal structure may be used as a sensor for detecting an aromatic organic solvent such as benzene, toluene and xylene.

In addition, in order to observe the color conversion according to the low refractive index layer thickness, the photonic crystal structures prepared in Examples 4 and 5 with different coating rates of the low refractive index dispersion composition were no longer added to benzene, toluene, xylene, ethanol and methanol, respectively. After soaking until no color change, the changed color was observed, and the photographs are shown in FIGS. 12A and 13A, respectively. In addition, the specular reflectances of the photonic crystal structures prepared in Examples 4 and 5 according to the solvent change were measured using a reflectometer (USB 4000, Ocean Optics), and the results are shown in FIGS. 12B and 13B, respectively. In this case, “initial” means the color of the photonic crystal structure before immersion in the solvent.

As shown in FIGS. 12 and 13, when the thickness of the high refractive index layer is changed, it can be seen that the reflection wavelength and the degree of shift of the photonic crystal structure are changed so that the color observed according to the change of the solvent is different. However, even if the thickness of the high refractive index layer is different, the shift of the reflection wavelength is the same in the order of ethanol, methanol, xylene, toluene and benzene, and thus a sensor for detecting aromatic organic solvents such as benzene, toluene and xylene It was confirmed that it can be used as.

In addition, it can be seen that the color conversion of the structure due to the presence of benzene, toluene, xylene, etc. can be easily visually confirmed when the thickness of the high refractive index layer is 20 to 70 nm.

Experimental Example  6: Measurement of specular reflectance according to the change of benzene concentration

The specular reflectance according to the concentration change of benzene vapor of the photonic crystal structures prepared in Examples 4 and 6 were measured using a reflectometer (USB 4000, Ocean Optics), and the results are shown in FIGS. 14 and 15, respectively.

As shown in Figs. 14 and 15, the photonic crystal structures prepared in Examples 4 and 6 exhibited a clear shift in reflection wavelength even with small changes in benzene of 25 to 75 ppm, and thus excellent sensitivity to changes in benzene concentration. can confirm. In addition, it can be seen that the reflection wavelength of the color conversion photonic crystal structure is shifted in the direction of increasing wavelength as the concentration of benzene increases. In this case, the shifted reflection wavelength corresponds to the visible light region, so that the change in the reflection wavelength of the photonic crystal structure can be observed with the naked eye. Therefore, the photonic crystal structure according to the embodiment can be used not only for qualitative analysis of organic solvent but also for quantitative analysis. Can be.

Experimental Example  7: On the refractive index layer  gun On stack  Specular reflectance

In order to confirm the tendency of specular reflectivity according to the total number of stacked layers of the refractive index layer of the photonic crystal structure, the specular reflectivity according to the concentration change of benzene vapor of the photonic crystal structures prepared in Examples 6 to 8 was measured using a reflectometer (USB 4000, Ocean Optics). ), And the results are shown in FIGS. 15 to 17, respectively.

15 to 17, it can be seen that the specular reflectivity increases as the total number of stacked layers of the refractive index layer increases. This means that as the number of alternating high refractive index layers and low refractive index layers is increased, constructive interference between partial reflection wavelengths of the layer boundary portion is strengthened, thereby increasing the intensity of the reflection wavelength.

Experimental Example  8: Measurement of Specular Reflectance on Silicon Wafer Substrates

In order to confirm the tendency of specular reflectivity according to the change of the substrate of the photonic crystal structure, the reflectance (USB 4000, Ocean Optics) is used to change the specular reflectivity when the photonic crystal structure of Example 9 is exposed to benzene vapor using a silicon wafer substrate. Was measured, and the results are shown in FIG.

As shown in FIG. 18, it can be seen that even though the thickness of the refractive index layer is thin due to the characteristics of the silicon wafer substrate, the specular reflectance is very high compared to the case of using the glass substrate. Therefore, it was confirmed that various types of photonic crystal structures could be manufactured according to the use by changing the type of substrate.

Experimental Example  9: reproducibility test

After dipping the photonic crystal structure prepared in Example 1 into benzene, toluene and xylene, respectively, the specular reflectance of the photonic crystal structure when there is no color change is measured using a reflectometer (USB 4000, Ocean Optics), and then The reproducibility was tested by repeating the cycle of measuring the specular reflectance of the photonic crystal structure when returning to the color of the photonic crystal structure before immersion 10 times. The results are shown in Figs. 19A, 19B and 19C, respectively.

As shown in FIGS. 19A to 19C, it can be seen that the photonic crystal structure prepared in Example 1 exhibits the reflection wavelength in the same range as the first cycle even after repeated several cycles for all solvents. This means that the color conversion photonic crystal structure is excellent in reproducibility.

Experimental Example  10: Response time test

In order to confirm the response speed of the photonic crystal structure, the photonic crystal structure prepared in Example 1 was immersed in benzene, toluene, xylene, ethanol and methanol, respectively, and the reflection wavelength over time was reflected on a reflectometer (USB 4000, Ocean Optics). Was measured using, and the results are shown in FIG.

As shown in FIG. 20, it can be seen that the photonic crystal structure prepared in Example 1 exhibits a response time within about 2 minutes due to a rapid shift in reflection wavelength with respect to most solvents.

Therefore, through Experimental Examples 9 and 10, it can be seen that when using the photonic crystal structure according to an embodiment of the present invention, a sensor having excellent reproducibility and showing a fast response speed can be manufactured.

Experimental Example  11.According to compounds that may be included as pseudo petroleum Color conversion  observe

In order to confirm the degree of color conversion according to various compounds, the photonic crystal structure prepared in Example 5 was no longer used in genuine gasoline (Gasoline, SK Energy Co., Ltd.), thinner (manufactured by Namyang Chemical Co., Ltd.), methanol, and toluene, respectively. After soaking until no color change, the changed color was observed, and the photograph is shown in FIG. 21A. In this case, "pristine" means the color of the photonic crystal structure before immersion in the compound. In addition, the specular reflectance of the photonic crystal structure prepared in Example 5 according to the genuine gasoline, methanol and toluene was measured using a reflectometer (USB 4000, Ocean Optics), and the results are shown in FIG. 21B.

In addition, after dipping the photonic crystal structure prepared in Example 5 until there is no more color change in benzene, toluene, xylene, ethanol and methanol, the changed color was observed, the photo is shown in Figure 22a. In addition, the specular reflectance of the photonic crystal structure prepared in Example 5 according to the compound type was measured using a reflectometer (USB 4000, Ocean Optics), and the results are shown in FIG. 22B.

As shown in FIG. 21 and FIG. 22, it can be seen that the reflection wavelength of the photonic crystal structure of the example is changed according to the kind of the compound to be contacted, so that the displayed color is different. In particular, when the photonic crystal structure is in contact with genuine gasoline, the change in reflection wavelength does not occur compared with before contact, and thus there is almost no color change, but an aromatic organic solvent such as benzene, toluene and xylene or an alcoholic organic such as ethanol and methanol In the case of contact with the solvent, it can be seen that the shift of the reflection wavelength is large, resulting in a clear color change. Moreover, the reflection wavelength and the shifted reflection wavelength of the photonic crystal structure correspond to the visible light region, so that the color conversion of the photonic crystal structure can be visually observed. Thus, it can be seen that the photonic crystal structure according to an embodiment of the present invention does not cause color conversion to genuine gasoline, but is suitable for detecting pseudo gasoline by causing color conversion only for pseudo gasoline.

The degree of reflection wavelength shift of the photonic crystal structure is larger in order of ethanol, methanol, xylene, toluene and benzene. This means that as described above, the values of the solubility parameters in the order of xylene, toluene and benzene increased, so that the degree of swelling of the polymer in the photonic crystal structure prepared in the above example increased in this order. Therefore, the type of aromatic organic solvent, such as benzene, toluene and xylene, included in the pseudo petroleum can be identified using the optical sensor including the photonic crystal structure.

Experimental Example  5: according to similar petroleum type Color conversion  observe

In order to check whether the similar gasoline in the form of toluene mixed with genuine gasoline can be detected, pseudo gasoline mixed with toluene in various ratios with genuine gasoline is manufactured, and the optical sensor manufactured in Example 5 is no longer used for the gasoline. After soaking until no color change, the changed color was observed, and the photograph is shown in FIG. 23A.

In addition, the specular reflectance of the optical sensor manufactured in Example 5 according to pseudo gasoline mixed with toluene at various ratios in the genuine gasoline was measured using a reflectometer (USB 4000, Ocean Optics), and the results are shown in Table 6 and It is shown in Figure 23b.

In addition, in order to check whether the pseudo gasoline in the form of methanol mixed with genuine gasoline can be detected, a pseudo gasoline in which methanol is mixed in various ratios with the genuine gasoline is prepared, and the optical sensor prepared in Example 5 is used for the pseudo gasoline. After soaking until no color change, the changed color was observed, and the photograph is shown in FIG. 24A. In addition, the specular reflectance of the optical sensor prepared in Example 5 according to pseudo gasoline mixed with methanol at various ratios in the genuine gasoline was measured using a reflectometer (USB 4000, Ocean Optics), and the result is shown in FIG. 24B. Indicated.

In addition, in order to determine whether it is possible to detect similar gasoline in the form of a mixture of thinner, toluene and methanol without using genuine gasoline, an analogous gasoline in which the thinner, toluene and methanol are mixed in various ratios is prepared, and thus the light prepared in Example 5 After soaking the sensor until there is no color change in the pseudo gasoline, the changed color was observed and the photograph is shown in FIG. 25A. In addition, the specular reflectance of the optical sensor prepared in Example 5 according to pseudo gasoline in which thinner, toluene and methanol were mixed at various ratios was measured by using a reflectometer (USB 4000, Ocean Optics), and the result is illustrated in FIG. 25B. Indicated.

As shown in FIGS. 23 to 25, the optical sensor of Example 4 is different from the genuine gasoline shown in FIG. 21 when contacted with various similar gasoline, and the reflection wavelength shift is clear according to the shape of the pseudo gasoline. Accordingly, it can be seen that it is possible to detect several types of similar gasoline in the market using the optical sensor according to an embodiment of the present invention.

[Description of the code]

10: color conversion photonic crystal structure 11: substrate

13: first refractive index layer 15: second refractive index layer

Claims (14)

1. A first refractive index layer comprising a first polymer exhibiting a first refractive index, alternately stacked; And a second refractive index layer comprising a second polymer exhibiting a second refractive index,

   The first refractive index and the second refractive index are different,

   One of the first polymer and the second polymer is a copolymer represented by Formula 1, color conversion photonic crystal structure:

   [Formula 1]

   

   (Wherein R ₁ and R ₂ are each independently hydrogen or C _1-3 alkyl,

   X ₁ is C1-10 fluoroalkyl,

   L ₁ is O or NH,

   Y ₁ is benzoylphenyl,

   The benzoylphenyl is unsubstituted or substituted with 1 to 4 substituents each independently selected from the group consisting of hydroxy, halogen, nitro, C _1-5 alkyl and C _1-5 alkoxy,

   n and m are each independently an integer of 1 or more,

   n + m is from 100 to 1,000).
2. The method according to claim 1, R ₁ and R ₂ are each independently hydrogen or methyl,

   X ₁ is fluoromethyl, difluoromethyl, trifluoromethyl, 1-fluoroethyl, 2-fluoroethyl, 1,1-difluoroethyl, 1,2-difluoroethyl, 2,2 -Difluoroethyl, 1,1,2-trifluoroethyl, 1,2,2-trifluoroethyl, 2,2,2-trifluoroethyl, 1-fluoropropyl, 2-fluoropropyl , 1,1-difluoropropyl, 1,2-difluoropropyl, 2,2-difluoropropyl, 1,1,2-trifluoropropyl, 1,2,2-trifluoropropyl, 2,2,2-trifluoropropyl, 1-fluorobutyl, 2-fluorobutyl, 1,1-difluorobutyl, 1,2-difluorobutyl, 2,2-difluorobutyl, Color converting photonic crystal structure, which is 1,1,2-trifluorobutyl, 1,2,2-trifluorobutyl or 2,2,2-trifluorobutyl.
3. The color conversion photonic crystal structure of claim 1, wherein the copolymer represented by Chemical Formula 1 has a molar ratio of n: m of 100: 1 to 100: 10 and a number average molecular weight of 10,000 to 100,000 g / mol.
4. The color converting photonic crystal structure of claim 1, wherein the other of the first polymer and the second polymer is a copolymer represented by the following Chemical Formula 2:

   [Formula 2]

   

   (In the meal,

   R ₃ and R ₄ are each independently hydrogen or C _1-3 alkyl,

   R ₁₁ is hydroxy, cyano, nitro, and _{amino, SO 3 H, SO 3 (} C 1- 5 alkyl), C _1-10 alkyl or C _1-10 alkoxy,

   a1 is an integer of 0 to 5,

   L ₂ is O or NH,

   Y ₂ is benzoylphenyl,

   The benzoylphenyl is unsubstituted or substituted with 1 to 4 substituents each independently selected from the group consisting of hydroxy, halogen, nitro, C _1-5 alkyl and C _1-5 alkoxy,

   n 'and m' are each independently an integer of 1 or more,

   n '+ m' is between 100 and 1,000).
5. The compound of claim 4, wherein R ₃ and R ₄ are each independently hydrogen or methyl, R 11 is methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, or tert-butyl, a1 is 0, 1 Or 2, a color conversion photonic crystal structure.
6. The color conversion photonic crystal structure according to claim 4, wherein the copolymer represented by Chemical Formula 2 has a molar ratio of n ': m' of 100: 1 to 100: 20 and a number average molecular weight of 10,000 to 300,000 g / mol.
7. The color conversion photonic crystal structure of claim 1, wherein the total number of stacked layers of the first refractive index layer and the second refractive index layer is 5 to 30 layers.
8. The color conversion photonic crystal structure according to claim 1, wherein the first refractive index layer is a low refractive index layer having a thickness of 30 to 100 nm, and the second refractive index layer is a high refractive index layer having a thickness of 20 to 70 nm.
9. The method according to claim 1,

   The reflection wavelength of the photonic crystal structure is shifted by an external stimulus,

   The external stimulus is due to a change in the concentration of the organic solvent, color conversion photonic crystal structure.
10. A color conversion photonic crystal sensor comprising the color conversion photonic crystal structure of claim 1.
11. Claims 1 to 9 pseudo-petroleum detection optical sensor comprising the color conversion photonic crystal structure of any one of claims.
12. The optical sensor of claim 11, wherein the reflection wavelength of the photonic crystal structure is shifted by swelling of the first polymer or the second polymer upon contact with pseudo petroleum.
13. The method according to claim 11,

    The pseudo-petroleum includes a thinner, an aromatic organic solvent, or an alcohol-based organic solvent, optical sensor for detecting similar petroleum.
14. Contacting the optical sensor of claim 11 with a sample; And

    Checking whether or not the color conversion of the photonic crystal structure of the optical sensor; pseudo oil detection method comprising a.

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