KR102515085B1 - Polymer layer and a manufacturing method of the polymer layer - Google Patents

Abstract

The present application prevents oxidation of the phase change material, has excellent environmental resistance, prevents a decrease in transmittance to visible light and a decrease in thermal discoloration efficiency in the infrared region, minimizes production cost, and can occur in a phase change material It is possible to provide a polymer layer that prevents toxicity from leaking out and a method for manufacturing the polymer layer.

Description

Polymer layer and a manufacturing method of the polymer layer}

This application relates to a polymer layer and a method for manufacturing the polymer layer.

Recently, various products have been released to save energy. Among them, smart windows that control infrared transmittance of sunlight entering the outside are attracting attention.

Vanadium dioxide (VO ₂ ) nanoparticles are representative compounds applied to smart windows. Vanadium dioxide (VO ₂ ) nanoparticles having monoclinic insulator properties undergo phase transition to a metal phase above the phase transition temperature based on a phase transition temperature (in other words, a critical temperature). This is called MIT (Metal-Insulator transition) characteristic and is a reversible reaction.

Vanadium dioxide (VO ₂ ) nanoparticles have almost no change in transmittance with temperature in the visible light region (wavelength range of about 400 to 700 nm), but phase transition in the infrared region (wavelength range of about 700 to 2,500 nm) according to MIT characteristics At a temperature below the temperature, it has a high infrared transmittance, and at a temperature higher than the phase transition temperature, it has a low infrared transmittance.

Smart windows with vanadium dioxide (VO ₂ ) nanoparticles set the phase transition temperature so that it is higher than the temperature in summer and lower than the temperature in winter, blocking infrared rays that increase the indoor temperature in summer and transmitting infrared rays in winter, enabling efficient energy use. are making it

A conventional smart window to which vanadium dioxide (VO ₂ ) nanoparticles are applied uses a film coated with vanadium dioxide (VO ₂ ) nanoparticles, and in order to apply a roll-to-roll process, low-concentration vanadium dioxide ( The VO ₂ ) nanoparticle solution was applied to a thin thickness of several hundred nanometers on the entire surface of the substrate. For example, in Patent Document 1, a graphene layer having at least one or more layers; Disclosed is a graphene-based VO ₂ laminate for smart windows including a vanadium dioxide layer formed on an upper surface of the graphene layer and one or more functional layers formed on at least one surface of the vanadium dioxide layer.

In order to manufacture a smart window to which vanadium dioxide (VO ₂ ) nanoparticles are applied, there is a method of directly applying a vanadium dioxide (VO ₂ ) nanoparticle solution on a glass substrate. However, the method of directly applying the vanadium dioxide (VO ₂ ) nanoparticle solution on the glass substrate has a problem in that it is difficult to achieve a large area.

As a way to increase the area, a method of manufacturing a film using a vanadium dioxide (VO ₂ ) nanoparticle solution and attaching the film to at least one surface of a glass substrate has been proposed.

However, the method of attaching the film to at least one surface of the glass substrate is oxidized to vanadium pentoxide (V ₂ O ₅ ) and trivanadium octoxide (V ₃ O ₈ ), etc., which do not have thermochromic properties due to oxygen in the air, or vanadium dioxide ( VO ₂ ) had problems such as leakage of its toxicity to the outside.

Here, in order to solve the above problem, a method of forming an encapsulation layer relatively thicker than a film prepared using a vanadium dioxide (VO ₂ ) nanoparticle solution on the film has been proposed.

However, when the protective layer is formed on the film, oxidation of vanadium dioxide (VO ₂ ) can be prevented and toxicity can be suppressed from leaking to the outside, but there is a problem that the production cost increases and the transmittance to visible light decreases. .

Republic of Korea Patent No. 10-1319263

The present application can provide a polymer layer capable of preventing oxidation of a phase change material and a method for manufacturing the polymer layer, while enabling large-area manufacturing.

In addition, the present application can provide a polymer layer having excellent environmental resistance, preventing a decrease in transmittance to visible light and a decrease in thermal discoloration efficiency in an infrared region, and minimizing a production cost and a method for manufacturing the polymer layer. there is.

In addition, the present application may provide a polymer layer that suppresses leakage of toxicity that may occur in a phase change material to the outside and a method for manufacturing the polymer layer.

The polymer layer according to an embodiment of the present application includes a polymer component and a phase change material, is in the form of a film or sheet, and has 9 points on the surface of the film or sheet form at equal intervals such that one point exists per 100 cm ² . The standard deviation of the transmittance for the wavelength at 550 nm at 25 ° C measured at each point measured at each point is 1 or less, and the T value according to Equation 1 below is 50% or more:

[Equation 1]

T = T _{550. AVG} +ΔT _{2000. AVG}

In Equation 1, T _550.AVG is the average transmittance for a wavelength of 550 nm at 25° C. at each of the nine points, and ΔT _2000.AVG is the average transmittance for a wavelength of 2000 nm at 25° C. at each of the nine points. It is the average of the difference (T _2000.25 -T _2000.90 ) between transmittance (T _2000.25 ) and transmittance (T _2000.90 ) for a wavelength of 2000 nm at 90°C.

A method for manufacturing a polymer layer according to an embodiment of the present application includes a first step of mixing a phase change material with a first monomer represented by Chemical Formula 1 or 2 below; a second step of mixing the mixture of the first step with a second monomer different from the first monomer; and a third step of curing the mixture of the second step:

[Formula 1]

In Formula 1, Q is hydrogen or an alkyl group, U is an alkylene group, Z is hydrogen or an alkyl group, and m is any number:

[Formula 2]

In Formula 2, Q is hydrogen or an alkyl group, A and U are each independently an alkylene group, X is a hydroxyl group or a cyano group, and n is an arbitrary number.

The polymer layer and the manufacturing method of the polymer layer according to an embodiment of the present application can prevent oxidation of the phase change material while enabling large-area manufacturing.

In addition, the polymer layer and the manufacturing method of the polymer layer according to an embodiment of the present application have excellent environmental resistance, prevent a decrease in transmittance to visible light and a decrease in thermochromic efficiency in the infrared region, and can minimize production cost. there is.

In addition, the polymer layer and the manufacturing method of the polymer layer according to an embodiment of the present application can suppress the leakage of toxicity that may occur in the phase change material to the outside.

Figure 1 shows i) transmittance for a wavelength of 550 nm at 25 ° C (T ₅₅₀ ) or ii) transmittance for a wavelength of 2,000 nm at 25 ° C (T _2000.25 ) and transmittance for a wavelength of 2,000 nm at 90 ° C in the present application. It shows nine points (black dots) for measuring the difference in transmittance (T _2000.90 ).
2 shows a graph of the transmittance according to the temperature of Example 1 measured at one point.

The term ultraviolet light used in this application refers to light having a wavelength ranging from about 10 nm to about 400 nm (including 10 nm but not including 400 nm).

Visible light, as a term used in this application, refers to light having a wavelength ranging from about 400 nm to about 700 nm (including 400 nm and excluding 700 nm).

Infrared, as a term used in this application, refers to light having a wavelength ranging from about 700 nm to about 2,500 nm (including 700 nm and excluding 2,500 nm).

The term thermochromic used in this application means that properties change according to temperature, and in particular, it may mean that light transmittance changes according to temperature. Specifically, the phase change material of the present application may have thermochromic color.

The term room temperature used in this application is a natural temperature that is not artificially increased or decreased, and may mean any temperature within the range of 10 ° C to 30 ° C, about 23 ° C or about 25 ° C depending on the season. . In addition, in describing certain physical properties in this application, unless otherwise specified in the case where the measurement temperature affects the corresponding physical properties, the corresponding physical properties are measured at room temperature.

Atmospheric condition, a term used in this application, is natural air pressure that is not artificially increased or decreased, and may mean a pressure of about 0.8 to 1.2 atm depending on altitude and atmospheric conditions.

Relative humidity, a term used in this application, is expressed as a percentage (%) of the ratio of the amount of water vapor currently contained in air in a unit volume to the maximum saturated vapor pressure that air in a unit volume can contain, It can be expressed as RH%.

Substitution, a term used in this application, means that a hydrogen atom bonded to a carbon atom of a compound is replaced with another substituent, and the position to be substituted is not particularly limited as long as the hydrogen atom is substituted, that is, the position where the substituent is substituted, and two In the case of more than one substitution, the substituents may be the same as or different from each other.

As used herein, the term substituent refers to an atom or group of atoms replacing one or more hydrogen atoms on the parent chain of a hydrocarbon. In addition, substituents are described below, but are not limited thereto, and the substituents may be further substituted with substituents described below or may not be substituted with any substituents unless otherwise specified in the present application.

An alkyl group or an alkylene group, which is a term used in this application, is a straight chain or branched chain having 1 to 20 carbon atoms, or 1 to 16 carbon atoms, or 1 to 12 carbon atoms, or 1 to 8 carbon atoms, or 1 to 6 carbon atoms, unless otherwise specified. It may be a chain alkyl group or an alkylene group, or a cyclic alkyl group or alkylene group having 3 to 20 carbon atoms, or 3 to 16 carbon atoms, or 3 to 12 carbon atoms, or 3 to 8 carbon atoms, or 3 to 6 carbon atoms. Here, the cyclic alkyl group or alkylene group includes an alkyl group or alkylene group having only a cyclic structure and an alkyl group or alkylene group having a cyclic structure. For example, both a cyclohexyl group and a methyl cyclohexyl group correspond to a cyclic alkyl group.

An alkenyl group or alkenylene group, which is a term used in this application, unless otherwise specified, is a straight chain or branched chain having 2 to 20 carbon atoms, or 2 to 16 carbon atoms, or 2 to 12 carbon atoms, or 2 to 8 carbon atoms, or 2 to 6 carbon atoms. chain acyclic alkenyl or alkenylene groups; It may be a cyclic alkenyl group or alkenylene group having 3 to 20 carbon atoms, or 3 to 16 carbon atoms, or 3 to 12 carbon atoms, or 3 to 8 carbon atoms, or 3 to 6 carbon atoms. Here, if a cyclic alkenyl group or alkenylene group is included, it corresponds to a cyclic alkenyl group or alkenylene group.

An alkynyl group or alkynylene group, which is a term used in this application, is a straight-chain or branched group having 2 to 20 carbon atoms, or 2 to 16 carbon atoms, or 2 to 12 carbon atoms, or 2 to 8 carbon atoms, or 2 to 6 carbon atoms, unless otherwise specified. Chain acyclic alkynyl group or alkynylene group, or a cyclic alkynyl group or alkynylene group having 3 to 20 carbon atoms, or 3 to 16 carbon atoms, or 3 to 12 carbon atoms, or 3 to 8 carbon atoms, or 3 to 6 carbon atoms it can be Here, if a cyclic alkynyl group or alkynylene group is included, it corresponds to a cyclic alkynyl group or alkynylene group.

The alkyl group, alkylene group, alkenyl group, alkenylene group, and alkynyl group may optionally be substituted with one or more substituents. In this case, the substituent is a group consisting of halogen (chlorine (Cl), iodine (I), bromine (Br), fluorine (F)), aryl group, heteroaryl group, ether group, carbonyl group, carboxyl group and hydroxyl group It may be one or more selected from, but is not limited thereto.

As used herein, the term aromatic or aromatic group includes an aryl group and a heteroaryl group.

As used herein, an aryl group refers to an aromatic ring in which one hydrogen is removed from an aromatic hydrocarbon ring, and the aromatic hydrocarbon ring may include a monocyclic or polycyclic ring. The aryl group is not particularly limited in carbon atoms, but unless otherwise specified, aryl having 6 to 30 carbon atoms, or 6 to 26 carbon atoms, or 6 to 22 carbon atoms, or 6 to 20 carbon atoms, or 6 to 18 carbon atoms, or 2 to 15 carbon atoms may be In addition, the term arylene group used in this application means that the aryl group has two bonding sites, that is, a divalent group. The description of the aryl group described above may be applied except that each is a divalent group.

A heteroaryl group, a term used in this application, is an aromatic ring containing one or more heteroatoms other than carbon, and specifically, the heteroatoms include nitrogen (N), oxygen (O), sulfur (S), selenium (Se) and tele One or more atoms selected from the group consisting of nium (Te) may be included. At this time, atoms constituting the ring structure of the heteroaryl group can be referred to as a reducing group. In addition, heteroaryl groups may include monocyclic or polycyclic rings. The heteroaryl group is not particularly limited in carbon atoms, but has 2 to 30 carbon atoms, or 2 to 26 carbon atoms, or 2 to 22 carbon atoms, or 2 to 20 carbon atoms, or 2 to 18 carbon atoms, or 2 to 15 carbon atoms, unless otherwise specified. It may be a heteroaryl group. In another example, the number of reducing atoms of the heteroaryl group is not particularly limited, but may be a heteroaryl group having 5 to 30, 5 to 25, 5 to 20, 5 to 15, 5 to 10, or 5 to 8 reducing atoms.

In addition, the term heteroarylene group used in this application means a heteroaryl group having two bonding sites, that is, a divalent group. The above description of the heteroaryl group may be applied except that each is a divalent group.

The aryl group or heteroaryl group may be optionally substituted with one or more substituents. In this case, the substituent is an alkyl group, an alkenylene group, an alkynylene group, a halogen (chlorine (Cl), iodine (I), bromine (Br), fluorine (F)), an aryl group, a heteroaryl group, ether group, it may be at least one selected from the group consisting of a carbonyl group, a carboxyl group and a hydroxyl group, but is not limited thereto.

As used in this application, the term (meth)acrylate refers to acrylic acid, methacrylic acid, a derivative of acrylic acid or a derivative of methacrylic acid.

A polymer layer according to an embodiment of the present application may include a polymer component and a phase change material.

The polymer component according to an embodiment of the present application may include a polymerization unit of a (meth)acrylate monomer.

The polymer component according to an embodiment of the present application may have a solubility parameter of a single polymer of 10 (cal/cm ³ ) ^1/2 or more, and in another example, 10 (cal/cm ³ ) ^1/2 to 15 (cal/cm ³ ) ^1/2 or 10 (cal/cm ³ ) ^1/2 to 13 (cal/cm ³ ) ^1/2 .

The solubility parameter means a solubility parameter of a homopolymer prepared by polymerizing a corresponding monomer, and through this, the degree of hydrophilicity and hydrophobicity of the corresponding monomer can be grasped. A method for obtaining the solubility parameter is not particularly limited and may follow a method known in the art. For example, the parameter may be calculated or obtained according to a method known in the art as a so-called Hansen solubility parameter (HSP).

When the solubility parameter of the polymer component according to an embodiment of the present application satisfies the above range, excellent dispersibility with the phase change material may be secured.

A polymer component according to an embodiment of the present application may include a polymerization unit of a monomer represented by Chemical Formula 1 or 2 below.

[Formula 1]

In Formula 1, Q is hydrogen or an alkyl group, U is an alkylene group, Z is hydrogen or an alkyl group, and m is an arbitrary number.

[Formula 2]

In Formula 2, Q is hydrogen or an alkyl group, A and U are each independently an alkylene group, X is a hydroxyl group or a cyano group, and n is an arbitrary number.

Examples of the alkylene group in Chemical Formulas 1 and 2 include an alkylene group having 1 to 20 carbon atoms, 1 to 16 carbon atoms, 1 to 12 carbon atoms, 1 to 8 carbon atoms, or 1 to 4 carbon atoms. The alkylene group may be linear, branched or cyclic. The alkyl group may be optionally substituted with one or more substituents.

Examples of the alkyl group present in Q and Z in Formulas 1 and 2 include an alkyl group having 1 to 20 carbon atoms, 1 to 16 carbon atoms, 1 to 12 carbon atoms, 1 to 8 carbon atoms, or 1 to 4 carbon atoms. The alkyl group may be straight chain, branched chain or cyclic. In addition, the alkyl group may be optionally substituted with one or more substituents.

In Formulas 1 and 2, m and n are arbitrary numbers, for example, each independently 1 to 100, 1 to 90, 1 to 80, 1 to 70, 1 to 60, 1 to 50, 1 to 40, 1 to 30, 1 to 20, 1 to 16, or 1 to 12.

In one example, in Formula 1, Q is hydrogen or an alkyl group having 1 to 4 carbon atoms, U is an alkylene group having 1 to 4 carbon atoms, Z is hydrogen or an alkyl group having 1 to 4 carbon atoms, and m is about 1 to 30 A phosphorus compound may be used, but is not limited thereto. Specifically, the monomer of Formula 1 is 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, etc. can

In the polymer layer according to an embodiment of the present application, the ratio of the polymerized unit of the monomer of Formula 1 or 2 in the polymer component is 40% by weight or more, 42.5% by weight or more, 45% by weight or more, 47.5% by weight or more, or 50% by weight. or more, 52.5% by weight or more, or 55% by weight or more, and in other examples, the ratio of polymerized units of the monomers represented by Formula 1 or 2 in the polymer component is 70% by weight or less, 67.5% by weight or less, 65% by weight or less, 62.5% by weight or less. It may be less than or equal to 60% by weight. The ratio of polymerized units of the monomers represented by formula (1) or (2) in the polymer component may be within a range formed by specifying the upper and lower limits listed above.

The polymer component according to an embodiment of the present application may further include a polymerization unit of a second monomer that is an alkyl (meth)acrylate or an aromatic (meth)acrylate. When the term second monomer is used in this application, the monomer of Chemical Formula 1 or 2 may be referred to as the first monomer.

The second monomer according to an embodiment of the present application is 2-ethylhexyl (meth)acrylate, isobutyl (meth)acrylate, methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate And lauryl (meth) acrylate and the like may be exemplified, but are not particularly limited thereto.

The polymerized unit of the second monomer according to an embodiment of the present application is 50 parts by weight or more, 55 parts by weight or more, or 60 parts by weight or more based on 100 parts by weight of the polymerized unit of the monomer of Formula 1 or 2 (ie, the first monomer). , 65 parts by weight or more or 70 parts by weight or more, and in another example, the polymerized unit of the second monomer is 100 parts by weight or less, 95 parts by weight or less relative to 100 parts by weight of the polymerized unit of the monomer of Formula 1 or 2 , 90 parts by weight or less, 85 parts by weight or less, or 80 parts by weight or less may be included. The polymerized unit content of the second monomer may be within a range formed by specifying the upper and lower limits listed above.

When the amount of polymerized units of the second monomer satisfies the above range, oxidation of the phase change material included in the polymer layer may be prevented and excellent environmental resistance may be secured.

The polymer layer according to an embodiment of the present application may further include a second polymer component that is a nonionic polymer having no physical and chemical interaction with the phase change material. When the term second polymer component is used in this application, the aforementioned polymer component may be referred to as the first polymer component.

The second polymer component according to an embodiment of the present application is polymethyl methacrylate (PMMA), polystyrene (PS), polycaprolactone (PCL), polyacrylonitrile (PAN), polyvinylidene fluoride (PVDF) , It may include at least one selected from the group consisting of polyvinylpyrrolidone (PVP) and polyvinyl alcohol (PVA), but is not particularly limited.

The polymer layer according to an embodiment of the present application may improve the dispersibility of the phase change material included in the polymer layer by including the second polymer component. When the dispersibility of the phase change material is improved, the difference in optical properties depending on the position can be minimized when the polymer layer is prepared in the form of a sheet or film.

The phase change material according to an embodiment of the present application may include vanadium dioxide (VO ₂ ) particles. As described above, vanadium dioxide (VO ₂ ) particles have almost no change in transmittance with temperature in the visible light region (wavelength range of about 400 to 700 nm), but according to the MIT characteristics, the infrared region (wavelength of about 700 to 2,500 nm) band) has a high infrared transmittance at a temperature below the phase transition temperature, and a low infrared transmittance at a temperature higher than the phase transition temperature.

Therefore, the polymer layer according to an embodiment of the present application sets the phase transition temperature to be higher than the temperature in summer and lower than the temperature in winter using vanadium dioxide (VO ₂ ) particles, thereby blocking infrared rays that increase the indoor temperature in summer and in winter It can transmit infrared rays.

Vanadium dioxide (VO ₂ ) particles included in the phase change material according to an embodiment of the present application may be obtained by pulverizing a vanadium dioxide (VO ₂ ) precursor. Here, the vanadium dioxide (VO ₂ ) precursor may mean a larger average particle size than the vanadium dioxide (VO ₂ ) particles used in the present application, and may be obtained commercially.

A method of pulverizing the vanadium dioxide (VO ₂ ) precursor is not particularly limited, but milling equipment may be used, for example. In addition, more specifically, after preparing a precursor slurry using a vanadium dioxide (VO ₂ ) precursor, metal beads are filled in the precursor slurry, sufficiently pulverized with the milling equipment, and then the metal beads The vanadium dioxide (VO ₂ ) precursor may be pulverized in a way to remove it.

The precursor slurry may include a vanadium dioxide (VO ₂ ) precursor and a polar solvent, and the polar solvent may be selected from the group consisting of water and an alcohol compound. Examples of the alcohol compound include methanol, ethanol, propanol, 2-butoxyethanol, and isopropyl alcohol, but are not limited thereto.

The metal beads are not particularly limited as long as they are generally used in the art, and examples thereof include zirconia beads. In addition, as long as the vanadium dioxide (VO ₂ ) precursor in the precursor slurry can be properly pulverized through milling, the content and size of the metal beads are not particularly limited.

Vanadium dioxide (VO ₂ ) particles included in the phase change material according to an embodiment of the present application may be synthesized by hydrothermal synthesis using a hydrothermal synthesis precursor and a reducing agent. Examples of the hydrothermal synthesis precursor include ammonium metavanadate (NH ₄ VO ₃ ), vanadium pentoxide (V ₂ O ₅ ) and vanadium sulfate (V ₂ SO ₄ ), but are not particularly limited, and the reducing agent is hydrazine. Hydrate (hydrazine monodydrate), hydrazine monohydrochloride (hydrazine monohydrochloride) and oxalic acid (oxalic acid) and the like can be exemplified, but are not particularly limited.

The average particle size of the vanadium dioxide (VO ₂ ) particles included in the phase change material may be 40 nm or more, 42 nm or more, 44 nm or more, 46 nm or more or 48 nm or more, in another example, 70 nm or less, 68 nm or less, 66 nm or less, 64 nm or less, or 62 nm or less.

At this time, the average particle size of the vanadium dioxide (VO ₂ ) particles is a so-called D50 particle size (median particle size), and may mean a particle size at 50% cumulative volume basis of the particle size distribution. That is, the particle size distribution is obtained on a volume basis, and the particle diameter at the point where the cumulative value is 50% in the cumulative curve with the total volume as 100% can be seen as the average particle diameter. The D50 particle diameter as described above can be measured by a laser diffraction method.

When the average particle size of the vanadium dioxide (VO ₂ ) particles satisfies the above range, excellent thermochromic properties may be secured.

The phase change material according to an embodiment of the present application is 0.01 wt% or more, 0.05 wt% or more, 0.1 wt% or more, 0.2 wt% or more, 0.3 wt% or more, 0.4 wt% or more, or 0.5 wt% or more based on the total weight of the polymer layer. In another example, the phase change material may be included in 2% by weight or less, 1.75% by weight or less, 1.5% by weight or less, 1.25% by weight or less, 1% by weight or less, or 0.75% by weight or less based on the total weight of the polymer layer. there is. The phase change material may be included within the range formed by specifying the upper and lower limits listed above relative to the total weight of the polymer layer.

In another example, the phase change material of the present application is included in an amount of 1 part by weight or more, 3 parts by weight or more, 5 parts by weight or more, 7 parts by weight or more, or 9 parts by weight or more based on 100 parts by weight of the polymerized unit of the monomer of Formula 1 or 2. In another example, the phase change material may be included in an amount of 20 parts by weight or less, 17.5 parts by weight or less, 15 parts by weight or less, or 12.5 parts by weight or less based on 100 parts by weight of the polymer unit of the first or second monomer. The phase change material may be included within the range formed by specifying the upper and lower limits listed above based on 100 parts by weight of the polymerized unit of the monomer of Formula 1 or 2.

In addition, when the content of the phase change material according to an embodiment of the present application satisfies the above range, dispersibility with the polymer component is ensured to reduce the difference in optical properties depending on the position when the polymer layer is manufactured in the form of a sheet or film. It can be minimized, and excellent thermochromic properties can be secured.

The polymer layer according to an embodiment of the present application may be in the form of a film or sheet, and the polymer layer may be a pressure-sensitive adhesive layer or an adhesive layer, but is not limited thereto and may be various other layers.

As described above, the polymer layer according to an embodiment of the present application may be in the form of a film or sheet.

In the polymer layer according to an embodiment of the present application, nine points on the surface of the film or sheet form are designated at equal intervals so that one point per 100 cm ² exists, and 550 nm at 25 ° C. measured at each point. The standard deviation of the transmittance with respect to the wavelength may be 1 or less, 0.9 or less, 0.8 or less, 0.7 or less, or 0.6 or less.

In addition, in the polymer layer according to an embodiment of the present application, 9 points on the surface of the film or sheet form are designated at equal intervals so that one point per 100 cm ² exists, and at 25 ° C. measured at each point. The standard deviation of the difference (T _2000.25 -T _2000.90 ) between the transmittance for a wavelength of 2,000 nm (T _2000.25 ) and the transmittance for a wavelength of 2,000 nm (T _2000.90 ) at 90 ° C is 0.9 or less, 0.8 or less, 0.7 or less, 0.6 or less, or It may be less than 0.5.

A method of designating 9 points at equal intervals so that one point exists per 100 cm ² may be to designate the same interval with the nearest points when any one of the 9 points is selected. .

Specifically, referring to FIG. 1, the polymer layer according to one embodiment of the present application is cut to a width of 30 cm and a length of 30 cm, so that each horizontal length is the same and each vertical length is the same, respectively. 3 virtual lines are drawn to divide the vertical and horizontal lines into quarters, and the points where the horizontally drawn virtual line and the vertical virtual line meet can be selected as nine points.

That is, the transmittance for a wavelength of 550 nm at 25°C is measured at nine points, and the standard deviation of the measured transmittance for a wavelength of 550 nm at 25°C is 1 or less, 0.9 or less, or 0.8 or less. , 0.7 or less, 0.6 or less, or 0.5 or less.

In addition, transmittance (T _2000.25 ) and transmittance (T 2000.90 ) for a wavelength of 2,000 nm at 25°C and 2,000 nm wavelength (T _2000.90 ) at 25°C were measured at 9 points, and then the difference between them (T _2000.25 -T _2000.90 ) Calculate , and the standard deviation of the difference (T _2000.25 - T _2000.90 ) may be 0.9 or less, 0.8 or less, 0.7 or less, 0.6 or less, or 0.5 or less.

Since the polymer layer according to an embodiment of the present application has little variation in transmittance or difference in transmittance according to points, it is possible to expand the polymer layer to a large area.

The polymer layer according to an embodiment of the present application may have a T value of 50% or more, 52.5% or more, 55% or more, or 57.5% or more according to Equation 1 below. T defined in Equation 1 of this application may be referred to as thermochromic performance in this application. In addition, excellent thermochromic performance in the present application may mean a case in which the T value defined in Equation 1 below is 50% or more, 52.5% or more, 55% or more, or 57.5% or more.

[Equation 1]

T = T _{550. AVG} +ΔT _{2000. AVG}

In Equation 1, T _550.AVG is the average transmittance for a wavelength of 550 nm at 25° C. at each of the nine points, and ΔT _2000.AVG is the average transmittance for a wavelength of 2,000 nm at 25° C. at each of the nine points. It is the average of the difference (T _2000.25 -T _2000.90 ) between transmittance (T _2000.25 ) and transmittance (T _2000.90 ) for a wavelength of 2,000 nm at 90°C.

In other words, T _550.AVG in Equation 1 measures the transmittance for a wavelength of 550 nm at 25 ° C. at each of the nine points described above, and transmittance for a wavelength of 550 nm at each of the measured 25 ° C. It can mean an arithmetic mean. In Equation 1, ΔT _2000.AVG measures the transmittance (T _2000.25 ) for a wavelength of 2,000 nm at 25 ° C and the transmittance (T _2000.90 ) for a wavelength of 2,000 nm at 90 ° C at the nine points described above, respectively. After calculating the difference between them (T _2000.25 -T _2000.90 ), it may mean the arithmetic mean of the difference (T _2000.25 -T _2000.90 ).

In the polymer layer according to an embodiment of the present application, nine points on the surface of the film or sheet form are designated at equal intervals so that one point per 100 cm ² exists, and 550 nm at 25 ° C. measured at each point. The average transmittance with respect to the wavelength may be 20% or more, 22.5% or more, 25% or more, 27.5% or more, or 30% or more. In this case, the average may be an arithmetic average.

In the polymer layer according to an embodiment of the present application, transmittance with respect to a wavelength of 2,000 nm measured at each of nine points on the surface of the film or sheet form at equal intervals so that one point per 100 cm ² exists. If the average of the difference (T _2000.25 -T _2000.90 ) between (T _2000.25 ) and transmittance (T _2000.90 ) for a wavelength of 2,000 nm at 90 ° C is 5% or more, 7.5% or more, 10% or more, 12.5% or more, or 15% or more can In this case, the average may be an arithmetic average.

The polymer layer according to an embodiment of the present application may have an absolute value of change rate of T _550.AVG according to Equation 2 below of 5% or less, 3% or less, 1% or less, 0.75% or less, or 0.5% or less.

[Equation 2]

T _550.AVG rate of change = 100×(T _550.AVG.aft - T _550.AVG.bef )/T _550.AVG.bef

In Equation 2, T _550.AVG.aft is T _550.AVG measured after maintaining the polymer layer at 20 ° C and 50 RH% for 30 days, and T _550.AVG.bef is the polymer before the 30-day maintenance T _550.AVG of the layer, where T _550.AVG is the average transmittance for a wavelength of 550 nm at 25° C. at each of nine points.

In the polymer layer according to an embodiment of the present application, the absolute value of the change rate of ΔT _2000.AVG according to Equation 3 below may be 15% or less, 12.5% or less, 10% or less, 9% or less, or 8% or less.

[Equation 3]

ΔT _2000.AVG rate of change = 100×(ΔT _2000.AVG.aft - ΔT _2000.AVG.bef )/ΔT _2000.AVG.bef

In Equation 3, ΔT _2000.AVG.aft is ΔT _2000.AVG measured after maintaining the polymer layer at 20° C. and 50 RH% for 30 days, and ΔT _2000.AVG.bef is maintained for 30 days. ΔT _2000.AVG of the polymer layer before, and ΔT _2000.AVG is the transmittance (T _2000.25 ) for a wavelength of 2000 nm at 25 ° C. at each of the nine points and for a wavelength of 2,000 nm at 90 ° C. It is the average of the difference (T _2000.25 - T _2000.90 ) of transmittance (T _2000.90 ).

In the polymer layer according to an embodiment of the present application, the absolute value of the T value change rate according to Equation 4 below may be 7% or less, 6% or less, 5% or less, 3% or less, or 1% or less. At this time, T is equal to the T value defined in Equation 1 above.

[Equation 4]

T value change rate = 100 × (T _aft -T _bef ) / T _bef

In Equation 4, T _aft is T measured after maintaining the polymer layer at 20 ° C. and 50 RH% for 30 days, T _bef is T of the polymer layer before maintaining for 30 days, and T is in Formula 1 It is equal to the defined T value.

The polymer layer according to an embodiment of the present application may have a gel fraction of 75% or more, 77.5% or more, 80% or more, or 82.5% or more according to the following gel fraction measurement formula. The gel fraction may be a value measured in the same way as the gel fraction measurement method of the physical property measurement method below.

[Gel fraction measurement formula]

Gel fraction (%) = 100 × W ₁ /W ₂

In the gel fraction measurement formula, W ₁ represents the dry weight of the insoluble content of the polymer layer after 72 hours of immersion in ethyl acetate at room temperature, and W ₂ represents the weight of the polymer layer.

The polymer layer according to one embodiment of the present application may have an appropriate thickness of 1 μm or more depending on the use. The thickness of the polymer layer is not particularly limited, but may be 10 μm or more, 20 μm or more, 30 μm or more, 40 μm or more, or 50 μm or more depending on the application, and in other examples, 100 μm or less, 90 μm or less, or 80 μm may be below.

A polymer layer according to an embodiment of the present application may be manufactured according to a method for manufacturing a polymer layer described below. In particular, in the case of going through a series of steps according to the manufacturing method of the polymer layer described below, a polymer layer having desired characteristics of the present application can be prepared.

A method for manufacturing a polymer layer according to an embodiment of the present application includes a first step of mixing a phase change material with a first monomer represented by Chemical Formula 1 or 2 below; a second step of mixing the mixture of the first step with a second monomer different from the first monomer; and a third step of curing the mixture of the second step.

[Formula 1]

In Formula 1, Q is hydrogen or an alkyl group, U is an alkylene group, Z is hydrogen or an alkyl group, and m is any number:

[Formula 2]

In Formula 2, Q is hydrogen or an alkyl group, A and U are each independently an alkylene group, X is a hydroxyl group or a cyano group, and n is an arbitrary number.

Since the phase change material and the first monomer (the monomer of Formula 1 or Formula 2) are the same as those mentioned in the polymer layer, a detailed description thereof will be omitted.

The method for manufacturing a polymer layer according to an embodiment of the present application may include mixing a phase change material and a nonionic polymer before the first step, and mixing the mixture of the phase change material and the nonionic polymer with a first monomer. .

In addition, the method for manufacturing a polymer layer according to an embodiment of the present application may perform a step of mixing a phase change material, a nonionic polymer, and a solvent before the first step, and mixing the mixture with the first monomer.

Here, the nonionic polymer is as described in the above-mentioned polymer layer, polymethyl methacrylate (PMMA), polystyrene (PS), polycaprolactone (PCL), polyacrylonitrile (PAN), polyvinylidene fluoro It may include at least one selected from the group consisting of fluoride (PVDF), polyvinylpyrrolidone (PVP) and polyvinyl alcohol (PVA), but is not particularly limited.

In addition, the solvent may be a polar or amphoteric solvent, for example, may be selected from the group consisting of water and alcohol compounds. Examples of the alcohol compound include methanol, ethanol, propanol, 2-butoxyethanol, and isopropyl alcohol, but are not limited thereto.

The term "first mixed solution" as used in this application means a mixture of a phase change material and a nonionic polymer, a mixture of a phase change material and a solvent, and a phase change before the first step in the method for manufacturing a polymer layer according to an embodiment of the present application. It may refer to a mixture of materials, nonionic polymers, and solvents.

In the primary mixed solution, the phase change material may be included in an amount of 5 wt% or more, 6 wt% or more, 7 wt% or more, 8 wt% or more, or 9 wt% or more, and in other examples, 15 wt% or less, 14 wt% or less, 13 12 wt% or less, or 11 wt% or less. The content of the phase change material in the first mixture may be included within the range formed by specifying the upper and lower limits listed above.

In the primary mixed solution, the nonionic polymer may be included in an amount of 5 parts by weight or more, 7 parts by weight or more, 9 parts by weight or more, 11 parts by weight or more, or 13 parts by weight or more based on 100 parts by weight of the phase change material, and in another example, 20 parts by weight Or less, 19 parts by weight or less, 18 parts by weight or less, 17 parts by weight or less, or 16 parts by weight or less may be included. The content of the nonionic polymer in the primary mixture may be included within the range formed by specifying the upper and lower limits listed above.

In the primary mixed solution, the solvent may be included in an amount of 800 parts by weight or more, 825 parts by weight or more, or 850 parts by weight or more based on 100 parts by weight of the phase change material, and in another example, 1,000 parts by weight or less, 950 parts by weight or less, or 900 parts by weight or less. can The content of the solvent in the primary mixture may be included within the range formed by specifying the upper and lower limits listed above.

When the phase change material, the nonionic polymer, and the solvent in the primary mixed solution satisfy the above content range, the dispersibility of the phase change material can be secured, and excellent visible light transmittance and excellent thermochromic properties can be secured. In particular, when the nonionic polymer is out of the above content range, the dispersibility of the phase change material in the second and tertiary mixtures described later as well as in the first mixture is lowered, and a polymer layer having low visible light transmittance can be formed. .

The term “secondary mixed solution” used in this application may refer to a mixture prepared in the first step in the method for manufacturing a polymer layer according to an embodiment of the present application. That is, the secondary mixed solution means a mixture in which the first mixed solution is mixed with the first monomer.

In the secondary mixture, the first monomer may be included in an amount of 700 parts by weight or more, 750 parts by weight or more, 800 parts by weight or more, or 850 parts by weight or more based on 100 parts by weight of the first mixture. It may be included in 1,300 parts by weight or less, 1,200 parts by weight or less, 1,100 parts by weight or less, 1,000 parts by weight or less, or 950 parts by weight or less based on 100 parts by weight of the tea mixture. The content of the first monomer in the secondary mixture may be included within the range formed by specifying the upper and lower limits listed above.

When the content of the first monomer in the secondary mixed solution satisfies the above range, dispersibility of the phase change material and excellent thermochromic properties may be secured.

The term tertiary mixed solution used in this application may refer to a mixture prepared in the second step in the method for manufacturing a polymer layer according to an embodiment of the present application. That is, the tertiary mixed solution means a mixture in which the second mixed solution is mixed with the second monomer.

In the tertiary mixture, the second monomer may be included in an amount of 50 parts by weight or more, 75 parts by weight or more, 100 parts by weight or more, 125 parts by weight or more, or 150 parts by weight or more based on 100 parts by weight of the secondary mixture. The second monomer may be included in an amount of 400 parts by weight or less, 350 parts by weight or less, 300 parts by weight or less, 250 parts by weight or less, 200 parts by weight or less, or 175 parts by weight or less based on 100 parts by weight of the secondary mixture. The content of the second monomer in the tertiary mixture may be included within the range formed by specifying the upper and lower limits listed above.

When the content of the second monomer in the tertiary mixed solution satisfies the above range, efficient curing is possible in the third step while securing excellent thermochromic properties.

In the method for manufacturing a polymer layer according to an embodiment of the present application, the second monomer may be an alkyl (meth)acrylate or an aromatic (meth)acrylate.

Since the second monomer is the same as mentioned in the aforementioned polymer layer, a detailed description thereof will be omitted.

In the method for manufacturing a polymer layer according to an embodiment of the present application, a polymer layer may be prepared by curing the tertiary mixed solution. In addition, the method for manufacturing a polymer layer according to an embodiment of the present application may manufacture a polymer layer while polymerizing and curing the tertiary mixed solution.

In the method for manufacturing a polymer layer according to an embodiment of the present application, the third step may be cured by active energy ray curing, moisture curing, thermal curing, or room temperature curing, but is not particularly limited. Here, active energy ray curing is performed by irradiation of active energy rays such as ultraviolet rays, moisture curing is performed by maintaining under appropriate moisture, and thermal curing is performed by applying appropriate heat, or room temperature curing. may be performed by maintaining at room temperature.

In the method for manufacturing a polymer layer according to an embodiment of the present application, an appropriate amount of photoinitiator is added to the tertiary mixed solution before the third step, and then the polymer layer is cured with active energy rays (eg, ultraviolet rays). can be manufactured

As the photoinitiator, commercially available Irgacure 1173 and Irgacure 184 known in the art may be used.

In the case of manufacturing the polymer layer by curing with active energy rays, it may be divided into pre-curing and main curing. The pre-curing may be performed until the viscosity of the tertiary mixed solution into which the photoinitiator is added is in the range of 5,000 to 20,000 cPs measured at room temperature. The main curing may be performed until the pre-cured material is completely cured.

In the method for manufacturing a polymer layer according to an embodiment of the present application, the above-described polymer layer may be prepared through a mixture having excellent dispersibility. Since the polymer layer is formed of a mixture having excellent dispersibility, it may have a gel fraction as described above and ultimately prevent a decrease in transmittance of visible light and a decrease in thermochromic efficiency in an infrared region.

The polymer layer according to an embodiment of the present application is attached to a glass substrate or a polymer substrate such as polyethylene terephthalate (PET), polyethylene (PE), and polyimide (PI), and then attached to a glass outer wall or window of a building to make smart It can be used as a window.

Here, the smart window can block infrared rays that increase the indoor temperature in summer and transmit infrared rays in winter. As such, efficient energy use may be possible with the smart window to which the polymer layer according to an embodiment of the present application is applied.

Hereinafter, the present application will be described through examples and comparative examples, but the scope of the present application is not limited due to the contents presented below.

Example 1

(1) Preparation of hydrothermal synthesis phase change material powder

Ammonium metavanadate (NH ₄ VO ₃ , Ammonium metavanadate), hydrazine monohydrate (N ₂ H ₄ H ₂ O, Hydrazine monohydrate) and distilled water (DI water) were mixed at 3.5:2:94.5 (NH ₄ VO ₃ : N ₂ H ₄ H ₂ O:DI water) was mixed so as to be sufficiently dispersed in a weight ratio to form a vanadium dioxide (VO ₂ ) hydrothermal synthesis precursor. For the vanadium dioxide (VO ₂ ) hydrothermal synthesis precursor, powdery vanadium dioxide (VO ₂ ) particles having a particle size of about 50 nm were obtained through hydrothermal synthesis equipment (supplier: Hanul Engineering Co., model name: HR-8300).

(2) Preparation of the primary mixed solution

The obtained vanadium dioxide (VO ₂ ) particles, polyvinylpyrrolidone (supplier: Sigma-aldrich, polyvinylpyrrolidone, PVP) and isopropyl alcohol (IPA) were mixed at 10:1.5:88.5 (VO ₂ particles: PVP) :IPA) was mixed in a weight ratio to prepare a first mixed solution. The primary mixed solution was further improved in dispersibility of vanadium dioxide (VO ₂ ) particles by using a sonicator.

(3) Preparation of the secondary mixture

A second mixed solution was prepared by mixing 4-hydroxybutyl acrylate (4-HBA) with the prepared first mixed solution in a weight ratio of 1:9 (first mixed solution: 4-HBA). The secondary mixed solution was mixed using a vortex mixer.

(4) Preparation of the tertiary mixed solution

A third mixed solution was prepared by mixing 2-ethylhexyl acrylate (2-EHA) with the prepared second mixed solution in a weight ratio of 6:4 (second mixed solution: 2-EHA), About 5 parts by weight of a photoinitiator (irgacure 184D, supplier: CIBA GEIGY) was additionally mixed with 100 parts by weight of the tertiary mixed solution. The third mixed solution was mixed using a vortex mixer.

(5) Pre-hardening of the tertiary mixture

The prepared tertiary mixture was pre-cured by irradiating light in the ultraviolet region with a mercury lamp. Pre-curing was performed until the viscosity of the tertiary mixture at room temperature ranged from 5,000 to 20,000 cPs.

(6) Main curing and preparation of polymer layer

An ultraviolet light curing device that applies the pre-cured tertiary mixture to a thickness of about 50 μm by blade coating or slot-die coating on one surface of a glass substrate and emits a light amount of 4 kW to 30 kW in the coated area Light having a wavelength of about 250 nm to 350 nm was irradiated for about 10 minutes to prepare a polymer layer.

Example 2

A polymer layer was prepared in the same manner as in Example 1, except that the pre-cured tertiary mixed solution was applied to one side of the glass substrate to a thickness of about 10 μm.

Example 3

A polymer layer was prepared in the same manner as in Example 1, except that the pre-cured tertiary mixed solution was applied to one side of the glass substrate to have a thickness of about 30 μm.

Example 4

A polymer layer was prepared in the same manner as in Example 1, except that the pre-cured tertiary mixed solution was applied to one side of the glass substrate to a thickness of about 70 μm.

Comparative Example 1

Mixture A was prepared by mixing 2-ethylhexyl acrylate (2-EHA) with the first mixture prepared in Example 1 at a weight ratio of 13.04:86.96 (first mixture: 2-EHA). did The quaternary mixed solution was mixed using a vortex mixer.

Mixture B was prepared by mixing 4-hydroxybutyl acrylate (4-HBA) with the prepared mixture A in a weight ratio of 46:54 (mixture A: 4-HBA), and the mixture B About 5 parts by weight of a photoinitiator (irgacure 184D, supplier: CIBA GEIGY) was additionally mixed with 100 parts by weight. Mixture B was mixed using a vortex mixer.

Thereafter, a polymer layer was prepared through pre-curing and main curing in the same manner as in Example 1.

Comparative Example 2

The primary mixture prepared in Example 1, 4-hydroxybutyl acrylate (4-HBA) and 2-ethylhexyl acrylate (2-EHA) were mixed at 9:54: Mixture C was prepared by mixing at a weight ratio of 40 (primary mixture: 4-HBA: 2-EHA), and about 5 parts by weight of photoinitiator (irgacure 184D, supplier: CIBA GEIGY) based on 100 parts by weight of the mixture C was further mixed. The mixed solution C was mixed using a vortex mixer.

Thereafter, a polymer layer was prepared through pre-curing and main curing in the same manner as in Example 1.

Comparative Example 3

About 5 parts by weight of the first mixture prepared in Example 1 compared to 100 parts by weight of the first mixture A photoinitiator (irgacure 184D, supplier: CIBA GEIGY) was further mixed, and the mixture was blade coated or slot-die coated on one side of the glass substrate so that the transmittance for a wavelength of 550 nm at 25 ° C was the same as in Example 1 was applied to a suitable thickness.

Thereafter, a polymer layer was prepared through pre-curing and main curing in the same manner as in Example 1.

<How to measure physical properties>

1. Transmittance measurement method in the visible ray region and transmittance difference measurement method by thermochromic color in the infrared region

The transmittance measurement method in the visible ray region and the transmittance difference measurement by thermochromic in the infrared region were performed only for the polymer layer on one side of the glass substrate in Examples 1 to 4 and Comparative Examples 1 to 3.

(1) Method for measuring transmittance in the visible ray region

Place the polymer layer immediately after production in an environment without external light and transmit light with a wavelength of 550 nm to the polymer layer using UV-VIS-NIR spectrometer equipment (supplier: Jasco, model name: V-670) at 25 ° C. Transmittance according to the light extinction method was measured by measuring the amount of light reduced by transmission.

Here, the polymer layer was cut to a width of 30 cm and a length of 30 cm, and as shown in FIG. 1, 9 points of the polymer layer were designated to measure transmittance in the visible ray region as described above.

Specifically, in order to designate the 9 points, three imaginary lines are drawn on each of the horizontal and vertical sides so that the polymer layer cut to 30 cm in width and 30 cm in length has the same horizontal length and the same vertical length. Vertical and horizontal were divided into 4 equal parts. Here, the nine points are selected as points where a horizontally drawn virtual line and a vertical virtual line meet (see FIG. 1). That is, 9 points are selected (one point per 100 cm ² ) on the entire 900 cm ² surface, and when any one of the 9 points is selected, the distance between the nearest points is the same. Then, the transmittance in the visible ray region was measured at each point.

T _550.AVG was calculated by taking the arithmetic mean of the transmittance of each visible ray region measured at the nine points. In addition, the standard deviation of the transmittance of each visible ray region measured at the nine points was also calculated.

In addition, after the polymer layer was left at about 20° C. and 50 RH% for 30 days from the production date, the transmittance in the visible ray region was measured in the same manner as above, and the T _550.AVG change rate was calculated according to Equation 2 below.

[Equation 2]

T _550.AVG rate of change = 100×(T _550.AVG.aft - T _550.AVG.bef )/T _550.AVG.bef

In Equation 2, T _550.AVG.aft is T _550.AVG measured after maintaining the polymer layer at 20 ° C and 50 RH% for 30 days, and T _550.AVG.bef is the polymer before the 30-day maintenance T _550.AVG of the layer, where T _550.AVG is the average transmittance for a wavelength of 550 nm at 25° C. at each of nine points.

(2) Method for measuring the difference in transmittance by thermochromic in the infrared region

Place the polymer layer immediately after production in an environment without external light and transmit light with a wavelength of 2,000 nm through the polymer layer using UV-VIS-NIR spectrometer equipment (Supplier: Jasco, Model: V-670) to reduce The transmittance according to the light extinction method was measured by measuring the amount of light emitted. Here, the absolute value of the difference between (a) transmittance (T _2000.25 ) measured at 25 ° C and (b) transmittance (T _2000.90 ) measured at 90 ° C was calculated.

Here, the polymer layer was cut to a width of 30 cm and a length of 30 cm, and as shown in FIG. 1, 9 points of the polymer layer were designated to measure the difference in transmittance due to thermochromic color in the infrared region as described above.

The 9 points were the same as the measurement positions in the method for measuring the transmittance in the visible ray region, and ΔT _2000.AVG is the difference in transmittance due to thermochromic color in the infrared region measured at each point among the 9 points. The arithmetic mean was calculated. In addition, the standard deviation of the difference in transmittance due to thermochromic color in the infrared region measured at each of the nine points was also calculated.

In addition, after the polymer layer was left at 20 ℃ and 50 RH% for 30 days from the production date, the difference in transmittance due to thermochromic discoloration in the infrared region was measured in the same way as above, and △T _2000.AVG according to the following formula 3 The rate of change was calculated.

[Equation 3]

ΔT _2000.AVG rate of change = 100×(ΔT _2000.AVG.aft - ΔT _2000.AVG.bef )/ΔT _2000.AVG.bef

In Equation 3, ΔT _2000.AVG.aft is ΔT _2000.AVG measured after maintaining the polymer layer at 20° C. and 50 RH% for 30 days, and ΔT _2000.AVG.bef is maintained for 30 days. ΔT _2000.AVG of the polymer layer before, and ΔT _2000.AVG is the transmittance (T _2000.25 ) for a wavelength of 2,000 nm at 25 ° C and the wavelength of 2,000 nm at 90 ° C at each of the nine points. It is the average of the difference (T _2000.25 - T _2000.90 ) of transmittance (T _2000.90 ).

2. Gel fraction measurement method

The polymer layer (glass substrate is not attached) prepared in Example 1 and Comparative Examples 1 and 3 A measurement sample was prepared by cutting to a width of 20 cm, a length of 20 cm, and a thickness of 50 μm. At this time, the mass of the polymer layer was measured.

In addition, the polymer layer was completely immersed in ethyl acetate and stored for 72 hours in a dark room at room temperature. Thereafter, a portion (insoluble content) not dissolved in ethyl acetate was obtained, and dried at 100° C. for 12 hours, and the mass (dry mass of insoluble content) was measured.

Subsequently, the gel fraction (unit: %) was measured by substituting the measurement result into the following formula.

[Gel fraction measurement formula]

Gel fraction (%) = 100 × W ₁ /W ₂

In the gel fraction measurement formula, W ₁ represents the dry weight of the insoluble content of the polymer layer after 72 hours of immersion in ethyl acetate at room temperature, and W ₂ represents the weight of the polymer layer.

<measurement result>

The difference in transmittance due to thermal discoloration in the visible light region and infrared region of the polymer layer according to the Examples and Comparative Examples is summarized in Tables 1 and 2 below.

division T _{-550. AVG} of T ₅₅₀
Standard Deviation △T _{2000. AVG} △T of ₂₀₀₀
Standard Deviation Example 1 30.4% 0.35 35.3% 0.34 Comparative Example 1 29.8% 1.26 35.2% 1.05 Comparative Example 2 30.3% 1.92 35.4% 1.48

Referring to Table 1, nine points of Example 1 are designated at equal intervals so that there is one point per 100 cm ² , and transmittance (T ₅₅₀ ) for a wavelength of 550 nm at 25° C. measured at each point The standard deviation of was 0.35, and the standard deviations of transmittance (T ₅₅₀ ) for a wavelength of 550 nm at 25° C. of Comparative Examples 1 and 2 were 1.26 and 1.92, respectively.

In addition, referring to Table 1, the difference between the transmittance (T _2000.25 ) for a wavelength of 2,000 nm at 25 ° C and the transmittance (T _2000.90 ) for a wavelength of 2,000 nm at 90 ° C (T _2000.25 -T _2000.90 at each of the nine points) The standard deviation of ) was 0.34, and the standard deviations of the differences in transmittance (T _2000.25 -T _2000.90 ) for the 2,000 nm wavelength of Comparative Examples 1 and 2 were 1.05 and 1.48, respectively.

It can be seen that the transmittance for the wavelength of 550 nm at 25 ° C. (T ₅₅₀ ) or the difference in transmittance for the 2,000 nm wavelength (T _2000.25 - T _2000.90 ) of Example 1 is concentrated near the average, and the comparison It can be seen that Examples 1 and 2, unlike Example 1, spread out from around the average.

Referring to Table 1, it can be seen that the polymer layer and the manufacturing method of the polymer layer according to an embodiment of the present application have a small transmittance or transmittance difference variation according to points, so that a large area can be achieved.

division T _{-550. AVG} of T _{550. AVG}
rate of change △T _{2000. AVG} Change rate of △T _2000.AVG T _{550. AVG} +ΔT _{2000. AVG} Rate of change of T _550.AVG +ΔT _2000.AVG Example 1 30.4% +0.329% 35.3% -0.567% 65.7% -0.152% Example 2 51.3% 0% 7.2% -6.944% 58.5% -0.855% Example 3 40.7% -0.246% 19.3% -2.591% 60.0% -One% Example 4 21.5% -0.465% 32.1% -0.312% 53.6% -0.373% Comparative Example 3 30.4% -3.947% 37.4% -10.16% 67.8% -7.375%

Referring to Table 2, the change rates of T _550.AVG of Examples 1 to 4 were 0.329%, 0%, -0.246% and -0.465%, respectively, and the rates of change of ΔT _2000.AVG were -0.567% and -6.944, respectively. %, -2.591% and -0.312%. In addition, the change rates of T _550.AVG +ΔT _2000.AVG were -0.152%, -0.855%, 1%, and -0.373%, respectively. Figure 2 shows a graph of transmittance according to temperature of Example 1 measured at one point, and referring to Figure 2, it can be seen that the polymer layer according to Example 1 has a difference in transmittance according to temperature, especially in the infrared region. there is.

In addition, referring to Table 2, the rate of change of T _550.AVG of Comparative Example 3 is -3.947%, the rate of change of ΔT _2000.AVG is -10.16%, and the rate of change of T _550.AVG +ΔT _2000.AVG is -7.375%.

Referring to Table 2, the polymer layer and the manufacturing method of the polymer layer according to an embodiment of the present application prevent oxidation of the phase change material by including the phase change material in the polymer component, have excellent environmental resistance, and have visible light It can be seen that the decrease in transmittance and the decrease in thermal discoloration efficiency in the infrared region are prevented.

The gel fractions of the polymer layers according to the Examples and Comparative Examples are summarized in Table 3 below.

division Example 1 Comparative Example 1 Comparative Example 3 gel fraction 83.3% 71.2% 3.3%

Referring to Table 3, the gel fraction of Example 1 was 83.3%, and Comparative Examples 1 and 3 were 71.2% and 3.3%, respectively. That is, it can be seen that Example 1 is formed as a mixture with higher dispersibility than Comparative Examples 1 and 3, and when a series of manufacturing processes according to Example 1 are followed, ultimately the transmittance to visible light is lowered and in the infrared region It can be seen that a polymer layer capable of preventing a decrease in thermal discoloration efficiency can be prepared.

Claims (16)

Including a first polymer component, a second polymer component and a phase change material,
The first polymer component includes a polymerized unit of a (meth)acrylate monomer,
The second polymer component is a nonionic polymer,
in the form of a film or sheet,
Nine points on the surface of the film or sheet are designated at equal intervals so that there is one point per 100 cm ² , and the standard deviation of the transmittance for the wavelength at 550 nm at 25° C. measured at each point is 1 or less. ego,
A polymer layer having a T value of 50% or more according to Equation 1 below:
[Equation 1]
T = T _{550. AVG} +ΔT _{2000. AVG}
In Equation 1, T _550.AVG is the average transmittance for a wavelength of 550 nm at 25° C. at each of the nine points, and ΔT _2000.AVG is the average transmittance for a wavelength of 2,000 nm at 25° C. at each of the nine points. It is the average of the difference (T _2000.25 -T _2000.90 ) between transmittance (T _2000.25 ) and transmittance (T _2000.90 ) for a wavelength of 2,000 nm at 90°C. The method of claim 1, wherein the difference (T 2000.25 _{-T 2000.90} ) between the transmittance (T _2000.25 ) for a wavelength of 2,000 nm at 25 ° C and the transmittance (T _2000.90 ) for a wavelength of 2,000 nm at 90 ° C at each of the nine points A polymer layer with a standard deviation of 0.9 or less. 3. The polymer layer according to claim 2, wherein the average transmittance for a wavelength of 550 nm at 25°C at each of the nine points is 20% or more. The polymer layer according to claim 1, wherein the absolute value of the change rate of T _550.AVG according to Equation 2 below is 5% or less:
[Equation 2]
T _550.AVG rate of change = 100×(T _550.AVG.aft - T _550.AVG.bef )/T _550.AVG.bef
In Equation 2, T _550.AVG.aft is T _550.AVG measured after maintaining the polymer layer at 20 ° C. and 50 RH% for 30 days, and T _550.AVG.bef is the polymer before the 30-day maintenance. T _550.AVG of the layer, where T _550.AVG is the average transmittance for a wavelength of 550 nm at 25° C. at each of nine points. The polymer layer according to claim 1, wherein the absolute value of the change rate of ΔT _2000.AVG according to Equation 3 below is 15% or less:
[Equation 3]
ΔT _2000.AVG rate of change = 100×(ΔT _2000.AVG.aft - ΔT _2000.AVG.bef )/ΔT _2000.AVG.bef
In Equation 3, ΔT _2000.AVG.aft is ΔT _2000.AVG measured after maintaining the polymer layer at 20° C. and 50 RH% for 30 days, and ΔT _2000.AVG.bef is maintained for 30 days ΔT _2000.AVG of the polymer layer before, and ΔT _2000.AVG is the transmittance (T _2000.25 ) for a wavelength of 2,000 nm at 25 ° C and the wavelength of 2,000 nm at 90 ° C at each of the nine points. It is the average of the difference (T _2000.25 - T _2000.90 ) of transmittance (T _2000.90 ). The polymer layer according to claim 1, wherein the first polymer component comprises polymerized units of monomers represented by Formula 1 or 2 below:
[Formula 1]

In Formula 1, Q is hydrogen or an alkyl group, U is an alkylene group, Z is hydrogen or an alkyl group, and m is any number:
[Formula 2]

In Formula 2, Q is hydrogen or an alkyl group, A and U are each independently an alkylene group, X is a hydroxyl group or a cyano group, and n is an arbitrary number. 7. The polymer layer according to claim 6, wherein the ratio of polymerized units of the monomers represented by Formula 1 or 2 in the first polymer component is in the range of 40 to 70% by weight. The polymer layer according to claim 6, wherein the first polymer component further comprises a polymerized unit of a second monomer that is an alkyl (meth)acrylate or an aromatic (meth)acrylate. [Claim 9] The polymer layer of claim 8, wherein the polymerized unit of the second monomer is included within the range of 50 to 100 parts by weight based on 100 parts by weight of the polymerized unit of the monomer of Chemical Formula 1 or 2. delete The polymer layer of claim 1, wherein the phase change material includes vanadium dioxide (VO ₂ ) particles. According to claim 1, The phase change material is included in the range of 0.01 to 2% by weight based on the total weight of the polymer layer. The polymer layer according to claim 1, which is a pressure-sensitive adhesive layer or an adhesive layer. A first step of mixing the phase change material and the nonionic polymer and mixing the mixture of the phase change material and the nonionic polymer with a first monomer represented by Chemical Formula 1 or 2 below;
a second step of mixing the mixture of the first step with a second monomer different from the first monomer; and
Method for producing a polymer layer comprising a third step of curing the mixture of the second step:
[Formula 1]

In Formula 1, Q is hydrogen or an alkyl group, U is an alkylene group, Z is hydrogen or an alkyl group, and m is any number:
[Formula 2]

In Formula 2, Q is hydrogen or an alkyl group, A and U are each independently an alkylene group, X is a hydroxyl group or a cyano group, and n is an arbitrary number. delete 15. The method of claim 14, wherein the second monomer is an alkyl (meth)acrylate or an aromatic (meth)acrylate.

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