KR100550805B1 - Humidity sensor comprising polymeric membrane - Google Patents

Abstract

The present invention is a vinyl monomer comprising a tertiary amine group, a vinyl monomer comprising a first copolymer and an alkyl halide group copolymerized with a first vinyl comonomer and a second vinyl comonomer, a first vinyl comonomer and a second vinyl comonomer A polymer membrane humidity sensor comprising a moisture absorbent formed by crosslinking a second copolymer copolymerized with each other through a quaternization reaction, comprising: a moisture absorbing membrane, an electrode maintaining electrical contact with the moisture absorbing membrane, and fixing the electrode A polymer membrane humidity sensor comprising an electrode snap and a terminal connecting the electrode to the outside, wherein the moisture sensitive membrane is a first air copolymerized with a vinyl monomer comprising a tertiary amine group, a first vinyl comonomer, and a second vinyl comonomer Quaternization of a vinyl monomer comprising a copolymer and an alkyl halide group with a second copolymer obtained by copolymerizing a first vinyl comonomer and a second vinyl comonomer Characterized by crosslinking through the reaction.

Therefore, there is an effect of providing a humidity sensor including a moisture absorption film excellent in moisture absorption characteristics.

Humidity sensor, Humidity membrane, Tertiary amine group, Alkyl halide group, Vinyl comonomer

Description

Humidity sensor comprising polymeric membrane

1 is a configuration diagram schematically showing an electrode of a polymer film humidity sensor according to the present invention.

Figure 2 is a graph showing the moisture sensitivity of the moisture-sensitive film used in the polymer film humidity sensor prepared according to the present invention.

3 is a temperature dependency graph of the polymer film humidity sensor manufactured according to the present invention.

4 is a frequency dependency graph of the polymer film humidity sensor manufactured according to the present invention.

5 is a graph showing the response time of the polymer film humidity sensor manufactured according to the present invention.

6 is a graph showing the water resistance of the polymer film humidity sensor manufactured according to the present invention.

The present invention relates to a polymer film humidity sensor. More specifically, the present invention provides a vinyl monomer comprising a tertiary amine group, a vinyl monomer comprising a first copolymer and an alkyl halide group copolymerized with a first vinyl comonomer and a second vinyl comonomer, and a first vinyl comonomer The present invention relates to a polymer film humidity sensor comprising a damping agent formed by crosslinking a second copolymer obtained by copolymerizing a divinyl comonomer with each other through a quaternization reaction.

Polymeric moisture-sensitive membranes for humidity detection usually use electrolyte polymers obtained by polymerization of vinyl monomers containing salts. However, most electrolyte polymers have a disadvantage in that they are dissolved in a condensation state or a humid state for a long time because they have high water solubility.

For this purpose, a method of introducing an electrolyte by copolymerizing with various hydrophobic monomers or by graft copolymerization to a hydrophobic polymer is used. Crosslinking using two or more polyfunctional monomers or a method of directly bonding an electrolyte gel to an electrode substrate such as alumina or glass has also been attempted. In addition, a method of introducing a functional group such as amine or phosphine, which may undergo quaternary chloride, into a polymer, mixing with a dihalide curing agent, and applying it to an electrode, and then applying a high crosslinking by thermal crosslinking is also applied.

In recent years, various methods such as improving water resistance have been applied by forming an interpenetrating polymer network (IPN) of an electrolyte polymer and a hydrophobic polymer. However, a humidity sensor including a moisture-sensitive film provided with water resistance is a situation in which only a limited portion of the above methods are used in consideration of the manufacturing process.

An object of the present invention is a vinyl monomer comprising a tertiary amine group, a vinyl monomer comprising a first copolymer and an alkyl halide group copolymerized with a first vinyl comonomer and a second vinyl comonomer, and a first vinyl comonomer and a second vinyl. The present invention provides a polymer film humidity sensor including a new moisture film formed by cross-linking a second copolymer copolymerized with a comonomer through a quaternization reaction.

In the polymer film humidity sensor according to the present invention, in the polymer film humidity sensor comprising a moisture sensitive film, an electrode for maintaining electrical contact with the moisture sensitive film, an electrode snap for fixing the electrode, and a terminal for connecting the electrode to the outside, Copolymerizes a vinyl monomer comprising a tertiary amine group with a first copolymer and an alkyl halide group copolymerized with a first vinyl comonomer and a second vinyl comonomer and a first vinyl comonomer with a second vinyl comonomer The second copolymer is crosslinked with each other through a quaternization reaction.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the polymer film humidity sensor according to the present invention, in the polymer film humidity sensor comprising a moisture sensitive film, an electrode for maintaining electrical contact with the moisture sensitive film, an electrode snap for fixing the electrode, and a terminal for connecting the electrode to the outside, Copolymerizes a vinyl monomer comprising a tertiary amine group with a first copolymer and an alkyl halide group copolymerized with a first vinyl comonomer and a second vinyl comonomer and a first vinyl comonomer with a second vinyl comonomer The second copolymer is cross-linked through a quaternization reaction with each other.

The polymer membrane humidity sensor is a vinyl monomer including tertiary amine groups, a vinyl monomer including tertiary amine groups, a first copolymer copolymerized with a second vinyl comonomer, and a vinyl monomer including an alkyl halide group. A humidity sensor electrode composed of a gold electrode and an electrode containing silver-palladium was deposited on two kinds of copolymer solutions capable of reacting with each other, the second copolymer copolymerized with the first vinyl comonomer and the second vinyl comonomer, It crosslinks by heating and forms a moisture sensitive film.

In the polymer film humidity sensor according to the present invention, in the polymer film humidity sensor comprising a moisture sensitive film, an electrode for maintaining electrical contact with the moisture sensitive film, an electrode snap for fixing the electrode, and a terminal for connecting the electrode to the outside, Copolymerizes the first copolymer obtained by copolymerizing a vinyl monomer including tertiary amine groups and one or more vinyl comonomers, and the vinyl monomer including all alkyl halide groups and quaternary ammonium salts in one molecule or one or two vinyl comonomers. The second copolymer is cross-linked through a quaternization reaction with each other.

Polymer membrane humidity sensor is a humidity sensitive agent whose impedance changes according to humidity. It contains all of the first copolymer, alkyl halide group and quaternary ammonium salt copolymerized with vinyl monomer including tertiary amine group and one or more vinyl comonomers. A humidity sensor electrode made of a gold electrode and an electrode containing silver-palladium was deposited on two kinds of copolymer solutions capable of reacting with each other, a second copolymer obtained by copolymerizing a vinyl monomer and one or two or more vinyl comonomers. It crosslinks by heating and forms a moisture sensitive film.

The vinyl monomer including the tertiary amine group constituting the first copolymer may be introduced into the first copolymer in an amount of 10 to 80% by weight. When the vinyl monomer including the tertiary amine group is included in less than 10% by weight, there may be a problem in that the solubility in water is increased because the degree of crosslinking of the moisture sensitive film is lowered. There may be changes in physical properties, such as deterioration, and it may affect the moisture absorption characteristics.

In addition, the vinyl comonomer may be included in the balance of the first copolymer excluding the vinyl monomer including the tertiary amine group. The use of a low glass transition temperature vinyl comonomer which increases the moisture-sensitizing properties and film flexibility of the moisture-sensitive film obtained by controlling the content of the vinyl comonomer improves the flexibility of the moisture-sensitive film obtained and the adhesion with the electrode.

The vinyl monomer including both the alkyl halide and the quaternary ammonium ion constituting the second copolymer may be introduced into the second copolymer in an amount of 10 to 80% by weight. When the vinyl monomer containing both the alkyl halide and the quaternary ammonium salt is included in less than 10% by weight, there may be a problem that the solubility in water is increased due to the low degree of crosslinking of the moisture-sensitive film. There may be a change in physical properties, such as a decrease in the flexibility of the moisture-sensitive film, and also affects the moisture-sensitive properties.

The vinyl monomer including the tertiary amine group constituting the first copolymer is 2- (N, N-dimethylaminoethyl) acrylate, 2- (N, N-dimethylaminoethyl) methacrylate, 2- (N, N-diethylaminoethyl) acrylate, 2- (N, N-diethylaminoethyl) methacrylate, 4-vinylpyridine, 2-vinylpyridine, allylamine, diallylamine, triallylamine or any of these It may be selected from the group consisting of two or more mixtures.

The vinyl monomer including both the alkyl halide group forming the second copolymer and the quaternary ammonium salt in one molecule may be used together with the tertiary amine used to form the first copolymer, and may be prepared by reaction with a dihalide compound. Can be. Monomers containing both halides and quaternary ammonium salts of the second copolymer are tertiary amines, such as 2- (N, N-dimethylaminoethyl) acrylate and 2- (N, N-dimethylaminoethyl) methacrylate. 2- (N, N-diethylaminoethyl) acrylate, 2- (N, N-diethylaminoethyl) methacrylate, 4-vinylpyridine, 2-vinylpyridine, allylamine, diallylamine, Selected from the group consisting of triallylamine or a mixture of two or more thereof, a compound containing two halogens (chlorine, bromine and iodine) as an alkyl group having 1 to 18 carbon atoms as a dihalide, and a cyclo compound having 5 to 6 carbon atoms Halogen-containing compounds, α, α'-dichloro-ortho-xylene, α, α'-dichloro-meth-xylene, α, α'-dichloro-para-xylene, α, α'-dibro Mother-ortho-xylene, α, α'-dibromo-meth-xylene, α, α'-dibromo-para-xylene or horns of two or more thereof It can be prepared by reacting a selected one from the group consisting of a compound.

As shown in Table 1 below, a vinyl monomer comprising a tertiary amine group, a first monomer prepared by copolymerizing a first vinyl comonomer and a second vinyl comonomer, and a vinyl monomer and a first vinyl copolymer including an alkyl halide group A second copolymer prepared by copolymerizing a monomer and a second vinyl comonomer was prepared. In the preparation of the copolymer, 80 g of 4-vinylpyridine, 10 g of n-butyl acrylate and 10 g of 2-hydroxyethyl methacrylate are first mixed as monomers, and the initiators α, α'-azobisisobutyronitrile are added thereto. 0.100 g was dissolved in 300 g of benzene, degassed, and then subjected to radical polymerization at 60 ° C. for 24 hours to synthesize one copolymer. After the polymerization was completed, methylene chloride was added and the solution was reprecipitated in n-hexane to give a copolymer. The reprecipitation process was repeated once more, followed by vacuum drying to obtain a white powdery copolymer (first copolymer). The other copolymer was mixed with 80 g of vinylbenzyl chloride, 10 g of n-butylacrylate and 10 g of 2-hydroxyethyl methacrylate, and 0.100 g of the initiator α and α'-azobisisobutyronitrile were dissolved in 300 g of benzene. Then, the mixture was put in a polymerization ampule and subjected to radical polymerization at 60 ° C. under nitrogen atmosphere for 12 hours to synthesize one copolymer. After the polymerization was completed, methylene chloride was added and reprecipitated in petroleum ether to obtain a copolymer. After repeating the reprecipitation process once more, vacuum drying in a vacuum oven at 50 ℃ to obtain a white powdery copolymer (second copolymer).

Hereinafter, preferred embodiments and comparative examples of the present invention will be described.

The following examples are intended to illustrate the invention and should not be understood as limiting the scope of the invention.

Experimental Example

Preparation of dimethyl 2-methacryloxyethyl 3-bromopropyl ammonium bromide as a vinyl monomer containing both the alkyl halide group and the quaternary ammonium salt forming the second copolymer in one molecule

1,3-dibromopropane (10 g) in a solution of 2- (N, N-dimethylaminoethyl) methacrylate (5,0 g, 30 mmol) and hydroquinone (0.1 g) in anhydrous acetonitrile (100 mL) , 39 mmol) was added dropwise for 30 minutes, and then reacted at room temperature for 5 hours. After the reaction was completed, the precipitated powder was filtered using a glass filter, and the solvent was distilled under reduced pressure not to exceed 40 ° C. After distillation, the obtained solid crystals were washed several times with ethyl ether and hexane, dried and recrystallized from acetonitrile / ethyl ether (1/1). The obtained product was analyzed by Fourier transform-infrared spectroscopy and nuclear magnetic resonance spectroscopy, and the results are as follows.

FT-IR (KBr, cm ^-1 ): 2820-3030 (alkyl CH), 1720 (C = 0), 1615 (C = C), 1400-1440 (-CN ⁺ ), 1210-1110 (C-0)

¹ H-NMR (D ₂ O, ppm): 5.9, 6.0 (d, 2H, H ₂ C = C), 4.2 (t, 2H, -OC H ₂ -CH ₂ -N), 3.6 (t, 2H, -C H ₂ Br), 3.4 (m, 4H, -C H ₂ -N ⁺ -C H _2- ), 3.1 (s, 6H, 2 -C H ₃ ), 1.9 (s, 3H, -H ₂ C = C (C H ₃ )-), 1.7 (m, 2H, -CH ₂ -C H ₂ -CH ₂ -Br)

Other examples of vinyl monomers containing both the alkyl halide group and the quaternary ammonium salt used in the present invention in one molecule can be prepared by a method similar to the above experimental example.

Examples 1-5

As shown in Table 1 below, a vinyl monomer including a terpolymer containing a tertiary amine group and a first copolymer copolymerized with one or two or more vinyl comonomers and an alkyl halide group and a quaternary ammonium salt in one molecule; A second copolymer prepared by copolymerizing one or two or more vinyl comonomers was prepared. In the preparation of the copolymer, 80 g of 4-vinylpyridine, 10 g of 2-ethylhexyl acrylate and 10 g of 2-hydroxyethyl methacrylate are first mixed as monomers, and the initiators α, α'-azobisisobutyro are added thereto. 0.100 g of nitrile was dissolved in 300 g of benzene and degassed, followed by radical polymerization at 60 ° C. for 24 hours to synthesize one copolymer. After the polymerization was completed, methylene chloride was added and the solution was reprecipitated in n-hexane to give a copolymer. The reprecipitation process was repeated once more, followed by vacuum drying to obtain a white powdery copolymer (first copolymer). The other copolymer is mixed with 80 g of dimethyl-2-methacryloxyethyl-3-bromopropyl ammonium bromide, 10 g of 2-ethylhexyl acrylate and 10 g of 2-hydroxyethyl methacrylate, where the initiators α, α ' 0.100 g of azobisisobutyronitrile was dissolved in 300 g of benzene, placed in a polymerization amplifier, and subjected to radical polymerization at 60 ° C. for 12 hours under a nitrogen atmosphere to synthesize one copolymer. After the polymerization was completed, methylene chloride was added and reprecipitated in petroleum ether to obtain a copolymer. After repeating the reprecipitation process once more, it was vacuum dried in a vacuum oven at 50 ℃ to obtain a white powdery copolymer (second copolymer).

20 g of the first copolymer was homogeneously dissolved in 400 g of dimethyl sulfoxide, prepared as a solution, and placed in a vial, and 20 g of the second copolymer was homogeneously dissolved in 400 g of dimethyl sulfoxide in a separate vial. Ready. Rapid mixing of the first copolymer solution and the second copolymer solution at a constant condition of 5 ° C. and 60% RH (relative humidity) is carried out in a small container, and the 20 humidity sensor electrodes are perpendicular to the jig. The electrode was coated with the electrode and deposited on the electrode to apply the moisture-sensitive film according to the present invention. The electrode to which the moisture-sensitive film was applied was left to stand at room temperature immediately while being horizontally dried for 10 minutes, and then gradually heated up at 60 ° C. for 1 hour to further carry out crosslinking reaction. After crosslinking progressed, it was vacuum-dried to form the electrode to which the crosslinked copolymer damping film was apply | coated. Benzyl chloride or triethylamine was added to a flask capable of reacting with vacuum to prevent changes over time due to the presence of an excess of pyridyl or benzyl groups. After standing still, it was immersed in boiling ethanol for 30 minutes to remove residual unreacted material, and then vacuum dried again to complete the manufacture of the humidity sensor.

On the other hand, the obtained humidity sensor was subjected to an environmental test under the conditions shown in Table 2, and the results are shown in Table 3 and Figures 3 and 4, respectively.

In addition, the electrical properties of the obtained humidity sensor were investigated. The humidity characteristics of the obtained humidity sensor were controlled by adjusting the humidity at 1㎑ and 1V of the LCR meter (Tabai model Espec PL-2G) when the temperature and temperature of the constant temperature and humidity chamber were equilibrated to 25 ° C and 30% RH relative humidity. The value was measured. Hysteresis was measured in the order of 20% RH → 95% RH, followed by 95% RH → 20% RH. The other temperature dependence coefficient was measured by changing the temperature of the constant temperature and humidity chamber to 15 ℃, 25 ℃, 35 ℃ according to the above procedure, the dependence of the resistance according to the frequency change is measured by changing the output to 100Hz, 1㎑ and 10㎑ It was. The response rate between low humidity and high humidity was measured at the relative humidity of 33% RH and 94% RH of saturated solution of MgCl ₂ · 6H ₂ O and saturated solution of K ₂ SO ₄ at 20 ℃.

The manufactured humidity sensors are shown in Fig. 2 at 20 to 95% RH, and the temperature dependence test results in Fig. 3, the frequency dependency test results in Fig. 4, the response speed in Fig. 5, and the water resistance in Fig. 6 are shown. The test results are shown.

As a result of synthesizing the above embodiments, it was confirmed that the humidity sensor according to the present invention has excellent moisture absorption characteristics as shown in the tables and drawings. In particular, it was confirmed that the first copolymer and the second copolymer having a large molecular weight can manufacture a humidity sensor having excellent water resistance through high crosslinking.

Since alkyl halides and tertiary amines can easily react with each other to form quaternary ammonium salts, copolymers containing alkyl halides and tertiary amines exhibit reactivity with each other, and these copolymers react with each other. The crosslinked product had a semi-IPN form, and it was confirmed that quaternary ammoniumation proceeded while forming highly crosslinked to prepare a moisture-sensitive film having excellent moisture absorption properties.

Therefore, according to the present invention, there is an effect of providing a humidity sensor having excellent moisture absorbing properties as well as providing a humidity sensor including the same. In recent years, an automation and control system, a humidifier for the purpose of a control system, moisture, dehumidification, air conditioning, drying It can be used as parts of the system, and provides humidity sensor that can be used for condensation prevention of automobile, video tape recorder (VTR), camcorder, facsimile sensor, high humidity sensor, low temperature humidity sensor, etc. It works.

Although the present invention has been described in detail only with respect to the described embodiments, it will be apparent to those skilled in the art that various modifications and variations are possible within the technical scope of the present invention, and such modifications and modifications are within the scope of the appended claims.

Claims (5)

delete A polymer film humidity sensor comprising a moisture sensitive film, an electrode for maintaining electrical contact with the moisture sensitive film, an electrode snap for fixing the electrode, and a terminal for connecting the electrode to the outside, wherein the moisture sensitive film has a vinyl monomer comprising a tertiary amine group And the first copolymer copolymerized with one vinyl comonomer and the second copolymer copolymerized with one vinyl comonomer and a vinyl monomer including both an alkyl halide group and a quaternary ammonium salt in one molecule, through a quaternization reaction. A vinyl monomer formed by crosslinking and comprising a tertiary amine group constituting the first copolymer is included in the first copolymer in an amount of 10 to 80% by weight, and an alkyl halide constituting the second copolymer. The vinyl monomer comprising a quaternary ammonium ion and at the same time is included in the second copolymer in an amount of 10 to 80% by weight Subtitles humidity sensor. The method of claim 2, The vinyl monomer containing the tertiary amine group is 2- (N, N-dimethylaminoethyl) acrylate, 2- (N, N-dimethylaminoethyl) methacrylate, 2- (N, N-diethylaminoethyl ) Acrylate, 2- (N, N-diethylaminoethyl) methacrylate, 4-vinylpyridine, 2-vinylpyridine, allylamine, diallylamine, triallylamine or mixtures of two or more thereof The polymer membrane humidity sensor, characterized in that selected. The method of claim 2, Vinyl monomers containing both the alkyl halide group and the quaternary ammonium salt in one molecule include 2- (N, N-dimethylaminoethyl) acrylate and 2- (N, N-dimethylaminoethyl) methacrylate as tertiary amines. 2- (N, N-diethylaminoethyl) acrylate, 2- (N, N-diethylaminoethyl) methacrylate, 4-vinylpyridine, 2-vinylpyridine, allylamine, diallylamine, Selected from the group consisting of triallylamine or a mixture of two or more thereof, a compound containing two halogens (chlorine, bromine and iodine) as an alkyl group having 1 to 18 carbon atoms as a dihalide, and a cyclo compound having 5 to 6 carbon atoms. Halogen-containing compounds, α, α'-dichloro-ortho-xylene, α, α'-dichloro-meth-xylene, α, α'-dichloro-para-xylene, α, α'-dibro Mother-ortho-xylene, α, α'-dibromo-meth-xylene, α, α'-dibromo-para-xylene or two of them The polymer film humidity sensors mixture by reacting the selected from the group consisting of, characterized in that selected from the group consisting of a compound to be produced. The method of claim 2, The vinyl comonomer includes carboxyl group-containing vinyl monomers such as acrylic acid, methacrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid and crotonic acid; Acid anhydride vinyl monomers such as maleic anhydride and itaconic anhydride; Hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, hydroxybutyl acrylate, hydroxybutyl methacrylate, hydroxyhexyl acrylate, hydroxyhexyl methacrylate Siloxane group-containing vinyl monomers; N-substituted amide vinyl monomers such as N, N-dimethyl acrylamide and N, N-dimethyl methacrylamide; Alkoxy acrylate vinyl monomers, such as methoxy ethyl acrylate, methoxy ethyl methacrylate, ethoxy ethyl acrylate, and ethoxy ethyl methacrylate; Vinyl acetate, vinyl propionate, N-vinylpyrrolidone, methylvinylpyrrolidone, vinylpyridine, vinylpiperidone, vinylpyrimidine, vinylpiperazine, vinylpyrazine, vinylpyrrole, vinylimidazole, vinyloxazole, vinyl Vinyl monomers such as morpholyl, N-vinyl carboxylic acid amide, styrene, α-methylstyrene, and N-vinyl caprolactam; Cyanoacrylate vinyl monomers such as acrylonitrile and methacrylonitrile; Epoxy group-containing acrylic monomers such as glycidyl acrylate and glycidyl methacrylate; Polyethylene glycol acrylate, polyethylene glycol methacrylate, polypropylene glycol acrylate, polypropylene glycol methacrylate, methoxy ethylene glycol methacrylate, methoxy polyethylene glycol methacrylate, methoxy polypropylene glycol acrylate, methoxy polypropylene methacrylate Glycol-based acrylic ester monomers such as glycol; Acrylic ester monomers such as tetrahydroperpril acrylate, tetrahydroperpril methacrylate and 2-methoxyethyl acrylate; Monomers such as isoprene, butadiene, isobutylene and vinyl ether; Or the polymer membrane humidity sensor, characterized in that selected from the group consisting of two or more of them.

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