KR101981697B1 - Moisture absorptive and desorptive polymer and material containing such polymer - Google Patents

Abstract

When the moisture absorptive and desorptive fine particles are added to impart a moisture absorptive and desorptive property to a coating film or a resin molded article, there arise problems such as appearance of white light, change of shape or the like when wetted with water. As a result of intensive studies, the inventors of the present invention have found that a coating film or a resin molded article containing such a vinyl-based polymer having a salt-type carboxyl group, a hydroxyl group and a crosslinking structure can achieve both high moisture absorptive and desorptive properties and excellent water resistance. . An object of the present invention is to provide a polymer capable of imparting a high moisture absorptive and desorptive property and a high moisture permeability to water, a polymer capable of imparting excellent water resistance, and a material containing such a polymer.
Wherein the polymer is a vinyl-based polymer containing 1-7 mmol / g of a salt-type carboxyl group and further containing 0.01 to 10 mmol / g of a hydroxyl group and having a crosslinking structure.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a moisture absorptive and desorptive polymer,

The present invention relates to a moisture absorptive and desorptive polymer capable of imparting a coating film or a resin molded article excellent in moisture absorptive and desorptive performance, moisture permeability and water resistance by being added to a coating film or a resin molded article, and a molded article containing the polymer.

Conventionally, inorganic hygroscopic agents such as lithium chloride, calcium chloride, magnesium chloride and phosphorus pentoxide have been used as means for removing moisture in air. These inorganic hygroscopic agents have a high moisture absorption rate and a high moisture absorption rate, It is liable to be liquefied to contaminate the other, to be difficult to mold, and to be difficult to regenerate. In addition, the moisture absorbers such as silica gel, zeolite, sodium sulfate, activated alumina, activated carbon and the like have a drawback that they have a low moisture absorption amount and a low moisture absorption rate, requiring a high temperature for regeneration. In addition, when the composition is blended with a paint or a resin to impart hygroscopicity, the resultant coating film or molded article is damaged with insufficient appearance such as lack of transparency and uniformity.

In addition, although Patent Document 1 discloses a high-moisture-resisting moisture-proofing fiber of an organic type, the fibrous form has good processability in itself, but is not suitable as an additive because it is difficult to uniformly mix it in a coating material or a resin . Further, in the case of obtaining fibers industrially, a certain fiber diameter is required, and therefore the surface area can not be made so large that there is a problem that the moisture absorptive and desorptive rate also becomes slow. In addition, when the reaction is carried out in a fibrous form, there is a problem that the reaction tends to be uneven and the production cost is increased.

On the other hand, in Patent Document 2, moisture absorptive and desorptive fine particles are described, and it is more preferable in terms of uniformity in addition to a paint, resin, and the like. However, due to its high hydrophilicity, coating films and resin molded articles obtained by adding these fine particles have problems in durability against water, that is, water resistance, such as appearance of white light or changes in shape when wetted with water.

Japanese Unexamined Patent Publication No. 5-132858 Japanese Patent Application Laid-Open No. 8-225610

As a result of intensive studies, the present inventors have found that a vinyl-based polymer containing a salt-type carboxyl group and containing a hydroxyl group and having a crosslinking structure has a high moisture absorptive and desorptive property, and a coating film or a resin- And the present invention has been completed. An object of the present invention is to provide a polymer capable of imparting a high moisture absorptive and desorptive property and a high moisture permeability by mixing with a material, a polymer capable of imparting excellent water resistance, and a material containing such a polymer.

That is, the above object of the present invention can be achieved by the following means.

(1) A moisture absorptive and desorptive polymer characterized by being a vinyl-based polymer containing 1-7 mmol / g of a salt-type carboxyl group and 0.01 to 10 mmol / g of a hydroxyl group and having a crosslinking structure.

(2) polymerizing a monomer mixture containing a vinyl monomer having a structure capable of forming a salt-type carboxyl group by hydrolysis, a vinyl monomer having a structure capable of generating a hydroxyl group by hydrolysis, and a crosslinkable vinyl monomer (1), characterized in that it is obtained by hydrolyzing a copolymer obtained by subjecting a water-insoluble polymer to hydrolysis.

(3) The moisture absorptive and desorptive polymer according to (1) or (2), wherein the form is particulate.

(4) A material containing the moisture absorptive and desorptive polymer according to any one of (1) to (3).

(5) A material obtained by molding a resin to which a moisture absorptive and desorptive polymer according to any one of (1) to (3) is added.

(6) A material to which the moisture absorptive and desorptive polymer according to any one of (1) to (3) is applied together with a binder resin.

(7) The material according to (5) or (6), wherein the resin has an electrophilic functional group.

(8) The material according to (5) or (6), wherein the resin is a urethane resin.

The moisture absorptive and desorptive polymer of the present invention has a high hygroscopic property and can be added to a material or the like to obtain a material having excellent hygroscopicity and moisture permeability. Further, since the moisture absorptive and desorptive polymer of the present invention contains a hydroxyl group, it can react with an electrophilic functional group such as an isocyanate group to form a bond. By using this property, a material chemically bonded to the moisture absorptive and desorptive polymer can be obtained. The material of the present invention has excellent moisture absorption performance and moisture permeability, and also has excellent water resistance.

1 is an infrared absorption spectrum of the hygroscopic fine particle 1. (Reference Example 1)
2 is an infrared absorption spectrum of the fine particles 9. (Reference Example 1)
3 is an infrared absorption spectrum of the hygroscopic fine particle 2. (Reference Example 2)
4 is an infrared absorption spectrum of the fine particle 10. (Reference Example 2)

The moisture absorptive and desorptive polymer of the present invention contains 1 to 7 mmol / g, preferably 3 to 7 mmol / g of a salt-type carboxyl group. The carboxyl group of the salt form is a polar group having high hydrophilicity for exhibiting hygroscopicity, and when it is desired to obtain a high hygroscopicity, it is preferable that the carboxyl group contains as many groups as possible. However, it is necessary to properly balance the ratio of the hydroxyl group and the crosslinking structure to be described later. In particular, when the polar group amount exceeds 7 mmol / g, the ratio of the crosslinkable structure that can be introduced becomes too small, Resulting in stickiness and a problem that the volume change due to water swelling becomes severe.

On the other hand, the lower the polar group amount, the lower the hygroscopic performance. Particularly when the polar group content is less than 1 mmol / g, a sufficient hygroscopic performance is often not obtained. Therefore, it is preferable that the polar group content is 1 mmol / g or more, and more preferably 3 mmol / g or more in view of moisture absorption performance.

Examples of the salt type of this salt type carboxyl group, that is, countercation include alkaline metals such as Li, Na, K, Rb and Cs, alkaline earth metals such as Be, Mg, Ca, Sr and Ba, , Other metals such as Mn, Ag, Fe, Co, and Ni, NH4, and amine. In addition, the fact that a carboxyl group in which H is a counter cation is coexisted with these salt type carboxyl groups does not deviate from the present invention at all. In this case, the ratio of the total carboxyl group to the salt-type carboxyl group is not particularly limited, but from the viewpoint of the moisture absorptive and desorptive rate, the proportion of the salt-type carboxyl group is better.

The moisture absorptive and desorptive polymer of the present invention contains 0.01 to 10 mmol / g, more preferably 0.01 to 9 mmol / g, and still more preferably 0.05 to 1 mmol / g of hydroxyl groups. The key that represents the greatest point of the present invention and exhibits excellent water resistance is that the moisture absorptive and desorptive polymer has a hydroxyl group. Although a polymer having a moisture-absorbing and moisture-absorbing group having a salt-type carboxyl group has been shown in the prior art, there is no report of having a hydroxyl group, and a polymer having moisture-absorbing and desorbing ability capable of forming a covalent bond by reaction with an electrophilic functional group such as an isocyanate group, The polymer was not known. It has not yet been known that the molded article or the like obtained by adding a moisture absorptive and desorptive polymer introduced with a hydroxyl group to a urethane resin or the like remarkably improves the water resistance.

The present inventors have found that a resin molded article having excellent water resistance can be obtained by introducing a hydroxyl group into a moisture absorptive and desorptive polymer and adding such a polymer to a resin such as a urethane resin or an isocyanate group-containing constituent component having an electrophilic functional group I found out. It is believed that this contributes to formation of covalent bonds by reaction with an electrophilic functional group such as an isocyanate group contained in the constituent components of the resin, formation of hydrogen bonds or ionic bonds by the hydroxyl groups themselves. It is considered that the mechanism of expression of the water resistance is not clear, but the affinity of the interface between the polymer of the present invention and the resin improves by the combination thereof. That is, it is considered that the interface is not decomposed and the whitening and deformation are suppressed even if there is a change in volume due to absorption and drying by increasing the affinity of the interface. Further, according to this mechanism, when the moisture absorptive and desorptive polymer of the present invention is incorporated into a resin, a binder, a matrix or the like, its strength, abrasion resistance and the like can be expected to be improved.

As described above, since the hydroxyl group is a functional group that exhibits water resistance, when it is desired to obtain a high water resistance, it is preferable that the hydroxyl group contains as many groups as possible. However, as described above, it is necessary to take an appropriate balance in proportion to the salt type carboxyl group and the cross-linking structure for exhibiting the hygroscopicity. Specifically, when the amount of the hydroxyl group exceeds 10 mmol / g, The ratio of the carboxyl group and the cross-linking structure is excessively reduced, the hygroscopic performance deteriorates, and water swelling becomes severe. On the other hand, when the hydroxyl group content is less than 0.01 mmol / g, the water resistance can not be sufficiently obtained. Further, in practical use, even if the amount of hydroxyl groups is 1 mmol / g or less, the effect of water resistance is obtained in many cases. In this case, the selection range of the amount of the salt type carboxyl group is widened.

The moisture absorptive and desorptive polymer of the present invention has a crosslinked structure. As the moisture absorptive and desorptive polymer of the present invention, a polymer containing a large amount of a salt type carboxyl group or a hydroxyl group having a high affinity with water may be tacky upon contact with water, swell vigorously in water, If such a polymer is blended into a resin or the like, there is a case that the properties are adversely affected. In the moisture absorptive and desorptive polymer of the present invention, such a problem is prevented from occurring by introducing a crosslinked structure.

The crosslinked structure employed in the present invention is not particularly limited as long as it is not physically and chemically modified as a result of moisture absorption and moisture absorption, and any structure such as crosslinking by covalent bonding, ionic crosslinking, intermolecular interaction of polymers, . Among them, a crosslinked structure by covalent bonding is most preferable from the viewpoint of being strong and stable.

The moisture absorptive and desorptive polymer of the present invention is composed of a vinyl-based polymer. Since the main chain of the vinyl-based polymer is composed of a carbon-carbon bond, the vinyl-based polymer is less likely to be chemically influenced by a polyamide-based polymer having a carbon-nitrogen bond or a carbon- It has an advantage that it is easy to carry out hydrolysis treatment, neutralization treatment and the like in introducing a carboxyl group and a hydroxyl group.

The form of the moisture absorptive and desorptive polymer per se in the present invention is not limited, but it can be used as an additive for various materials in various applications in the case of particulates such as emulsions and powders. In the case of such particulate phase, the size of the particles can be suitably selected according to the application and is not particularly limited. However, when the average particle diameter is preferably 1000 占 퐉 or less, more preferably 100 占 퐉 or less, Practical value becomes large. In addition, the lower limit is not particularly limited. If it is an emulsion phase, it is preferably 0.03 占 퐉 or more, and more preferably 0.05 占 퐉 or more from the viewpoint of ease of manufacture. In the case of the suspension polymerization, the average particle diameter is about 1 to 5 mu m.

With respect to the moisture absorptive and desorptive performance of the moisture absorptive and desorptive polymer of the present invention, it is preferable that the saturated moisture absorptivity of the moisture absorptive and desorptive polymer in an atmosphere at 20 캜 and a relative humidity of 65% is 10% by weight or more, more preferably 20% by weight or more. When the saturated moisture absorption rate is less than 10% by weight, practical value is reduced because it is inferior to ordinary moisture absorbing materials such as rayon and wool. On the other hand, although the upper limit is not particularly limited, the saturated moisture absorption rate at 20 캜 and 65% relative humidity is preferably 70% by weight or less, Or less, more preferably 65 wt% or less.

Next, a method for producing the moisture absorptive and desorptive polymer of the present invention described above will be described. The moisture absorptive and desorptive polymer of the present invention is a vinyl polymer having a salt type carboxyl group, a hydroxyl group and a crosslinked structure as an essential structure. Methods for introducing these essential structures are roughly divided into a method of introduction during polymerization and a method of introduction after polymerization . The introduction method will be described in detail below for each structure. These introduction methods may be carried out so as to sequentially introduce the respective structures, but in practice, it is more preferable to carry out the production so that the respective structures are introduced in combination in a suitable combination of introduction methods for each of these structures.

First, a method of introducing a salt-type carboxyl group into the vinyl-based polymer is not particularly limited. Examples thereof include a method of obtaining a polymer using a monomer having a salt-type carboxyl group as a copolymerization component, a method of using a monomer having a carboxyl group as a copolymerization component A method in which a polymer is obtained and then converted into a salt form, a method in which a carboxyl group is introduced by a chemical modification into a polymer obtained by using a monomer having a structure convertible to a carboxyl group by chemical modification as a copolymerization component, And the above-mentioned three methods are carried out by graft polymerization.

Examples of the method for obtaining a polymer using a monomer having a salt-type carboxyl group as a copolymerization component include a method in which a vinyl and / or vinylidene salt type monomer containing a carboxyl group such as acrylic acid, methacrylic acid, maleic acid, itaconic acid, Is used as a copolymerization component.

As a method for obtaining a polymer by using a monomer having a carboxyl group as a copolymerization component and converting it into a salt form, there can be mentioned, for example, a copolymer obtained by using a vinyl and / or vinylidene monomer containing a carboxyl group as described above as a copolymerization component To a salt form. There are no particular restrictions on the method for converting the carboxyl group into a salt form. The method for producing the carboxyl group is not particularly limited and examples thereof include alkali metal ions such as Li, Na, K, Rb and Cs, alkaline earth metal ions such as Be, Mg, Ca, Sr and Ba, , A method in which a solution containing a large amount of other metal ions such as Al, Mn, Ag, Fe, Co, and Ni, and organic cations such as NH4 and amine is acted to perform ion exchange.

As a method of introducing a carboxyl group by chemical modification, for example, a hydrolysis treatment is performed to a polymer obtained by using a monomer having a structure capable of obtaining a carboxyl group as a copolymerization component to introduce a carboxyl group, And if not, a method of making a salt by the above-mentioned method can be mentioned. Examples of the monomer having a structure capable of obtaining a carboxyl group by hydrolysis include monomers having a cyano group such as acrylonitrile and methacrylonitrile; (Meth) acrylate, ethyl (meth) acrylate, normal propyl (meth) acrylate, isopropyl (meth) acrylate and isobutyl (meth) acrylate, and derivatives thereof such as acrylic acid, methacrylic acid, maleic acid, itaconic acid and vinyl propionic acid. Propyl (meth) acrylate, n-butyl (meth) acrylate, n-octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, hydroxylethyl (meth) acrylate, Amides such as acrylamide, monoethyl (meth) acrylamide and normal-t-butyl (meth) acrylamide can be exemplified. Other methods of introducing a carboxyl group by chemical modification include oxidation of alkenes, alkyl halides, alcohols, aldehydes, and the like.

There are no particular restrictions on the method for introducing a hydroxyl group into the vinyl-based polymer, and examples thereof include a method of obtaining a polymer by using a monomer having a hydroxyl group as a copolymerization component, a method of obtaining a monomer having a structure convertible to a hydroxyl group , A method of introducing a hydroxyl group by chemical modification or a method of carrying out the above two methods by graft polymerization.

Examples of the method for obtaining a polymer by using a monomer having a hydroxyl group as a copolymerization component include vinyls containing hydroxyl groups such as 4-hydroxyl butyl acrylate, hydroxyl ethyl (meth) acrylate and hydroxypropyl methacrylate, And / or a method of using a vinylidene monomer as a copolymerization component.

As a method of introducing a hydroxyl group by chemical modification, a copolymer obtained by using, for example, vinyl acetate, vinyl propionate, vinyl t-butanoate, vinyloxytrimethylsilane, or the like as a copolymerization component is hydrolyzed to obtain a hydroxyl group And a method of introducing a vinyl ether such as ethyl vinyl ether, methyl vinyl ether, isobutyl vinyl ether, propyl vinyl ether, t-pentyl vinyl ether, 2-chloroethyl vinyl ether, Trifluoroethyl vinyl ether or the like as a copolymerization component is subjected to a treatment with hydrogen halide or Lewis acid to introduce a hydroxyl group.

The method of introducing the crosslinking structure into the vinyl polymer is not particularly limited and includes a method of polymerizing a crosslinkable vinyl monomer as a copolymerization component in the polymerization step or a method of post-crosslinking with a reactive compound after polymerization And the introduction of a crosslinked structure by physical energy. Particularly, it is possible to introduce strong bridging by covalent bonding in the method of using the crosslinkable monomer in the polymerization step and the method of crosslinking after using the reactive compound after obtaining the polymer, and it is possible to introduce strong bridging by covalent bonding.

As the monomer used in the method using the crosslinkable vinyl monomer, a monomer having a plurality of vinyl groups can be used. (Meth) acrylate, triethylene glycol di (meth) acrylate, triethyleneglycol di (meth) acrylate, triethyleneglycol dimethacrylate, triethyleneglycol dimethacrylate, N-methylol acrylamide, hydroxyethyl methacrylate, Methylol propacrylate (meth) acrylate, methylene bisacrylamide, and divinylbenzene.

In selecting the crosslinkable vinyl-based monomer, it is preferable to select the crosslinkable vinyl-based monomer from the viewpoint of the salt-type carboxyl group and the introduction method of the hydroxyl group described above. For example, in the case of using a vinyl-based monomer containing a carboxyl group, it is preferable to select one that can withstand an acidic atmosphere by such a monomer, and when a hydroxyl group or a carboxyl group is introduced by a hydrolysis reaction, It is preferable to select not to use it. In view of being able to withstand such an acidic atmosphere or hydrolysis, among the above-mentioned examples, a crosslinked structure of divinylbenzene is suitable.

There is also no particular limitation on the method of introducing the crosslinking structure by crosslinking after using the reactive compound. For example, a hydrazine compound or a formaldehyde may be added to the nitrile group contained in the nitrile-based polymer obtained from the vinyl monomer having nitrile group Followed by reacting and introducing a crosslinked structure. Among them, the method of using a hydrazine compound is preferable in view of being stable to an acid and an alkali, and further, since the resulting crosslinked structure itself is hydrophilic, it can contribute to improvement of hygroscopicity. Further, the crosslinked structure obtained by the reaction of the nitrile group and the hydrazine compound is not known in detail, but is presumed to be based on a triazole ring or a tetrazole ring structure.

The method for introducing the salt-type carboxyl group, the hydroxyl group and the cross-linking structure in the production of the moisture absorptive and desorptive polymer of the present invention is as described above, but needless to say, the vinyl type monomer not involved in the introduction of these essential structures in the polymerization is appropriately selected It may be used as a copolymerization component.

The vinyl-based monomer that can be selected as such a copolymerizable component is not particularly limited, and examples thereof include halogenated vinyl compounds such as vinyl chloride, vinyl bromide, and vinyl fluoride; Vinylidene monomers such as vinylidene chloride, vinylidene bromide, and vinylidene fluoride; Unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid and itaconic acid, and salts thereof; Acrylic acid esters such as methyl acrylate, ethyl acrylate, butyl acrylate, octyl acrylate, methoxyethyl acrylate, phenyl acrylate, and cyclohexyl acrylate; Methacrylic acid esters such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, octyl methacrylate, phenyl methacrylate and cyclohexyl methacrylate; Unsaturated ketones such as methyl vinyl ketone, ethyl vinyl ketone, phenyl vinyl ketone, methyl isobutenyl ketone, and methyl isopropenyl ketone; There may be used vinyl monomers such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl monochloroacetate, vinyl dichloroacetate, vinyl trichloroacetate, vinyl monofluoroacetate, vinyl difluoroacetate and vinyl trifluoroacetate Vinyl esters; Vinyl ethers such as methyl vinyl ether and ethyl vinyl ether; Acrylamide and its alkyl substituents; Vinyl group-containing acid compounds such as vinyl sulfonic acid, allylsulfonic acid, methallylsulfonic acid, styrenesulfonic acid, 2-acrylamide-2-methylpropanesulfonic acid, sulfopropyl methacrylate, vinyl stearic acid, Or a salt thereof, an anhydride thereof, a derivative thereof and the like; Styrene, such as styrene, methylstyrene and chlorostyrene, and alkyl or halogen substituents thereof; Allyl alcohol and its esters or ethers; Vinyl imides such as N-vinylphthalimide and N-vinylsuccinimide; Basic vinyl compounds such as vinylpyridine, vinylimidazole, dimethylaminoethyl methacrylate, N-vinylpyrrolidone, N-vinylcarbazole and vinylpyridines; And unsaturated aldehydes such as acrolein and methacrylolane.

Preferable examples of the moisture absorptive and desorptive polymer employed in the present invention include a crosslinked structure of divinylbenzene and vinyl polymer particles having a salt-type carboxyl group and a hydroxyl group. In this case, the amount of divinylbenzene to be used is not particularly limited and may be set so as to achieve a desired function, but it is preferable that the amount of divinylbenzene is 3 to 40% by weight based on the total monomers usually used. When the content is less than 3% by weight, the obtained particles may swell in water significantly, resulting in remarkable tackiness. On the other hand, when the amount is more than 40% by weight, the amount of the salt-type carboxyl group is decreased, so that sufficient moisture absorption performance may not be obtained.

As a method for producing such vinyl-based polymer particles, the above-described method may be employed. For example, a method of graft-polymerizing a vinyl-based polymer with a vinyl-based monomer having a divinylbenzene group and a carboxyl group and a hydroxyl group, , A method of copolymerizing a vinyl-based monomer having a carboxyl group and a vinyl-based monomer having a hydroxyl group, and the like. However, from the viewpoint that it is easy to produce, and the cross-linking density, the amount of the salt-type carboxyl group and the amount of the hydroxyl group can be easily controlled, , A vinyl monomer having a structure capable of forming a salt-type carboxyl group by hydrolysis, a vinyl monomer having a structure capable of forming a hydroxyl group by hydrolysis, and optionally, a copolymer obtained by copolymerizing other vinyl monomer It is easy to use a method of hydrolyzing the cohesion.

The moisture absorptive and desorptive polymer of the present invention described above is useful as an additive for enhancing moisture absorptive and desorptive performance and moisture permeability of various materials. Here, the material to which the moisture absorptive and desorptive polymer of the present invention can be applied is not particularly limited, and examples thereof include fibers, paper, nonwoven fabric, yarn, fabric, knitted fabric, leather, coating film, film, sheet, can do. Among them, when applied to materials such as paper, nonwoven fabric, yarn, fabric, knitted fabric, foam and the like, it has a large contact area with the gas and excellent form retention property.

The method of containing the moisture absorptive and desorptive polymer of the present invention is not particularly limited as long as the moisture absorptive and desorptive polymer of the present invention is used in these materials. The moisture absorptive and desorptive polymer may be directly incorporated into a material, And the like. When the moisture absorptive and desorptive polymer of the present invention has a fibrous form, a method of obtaining a paper or nonwoven fabric by using a fibrous moisture absorptive and desorptive polymer as the constituent fiber may be employed.

The method of kneading into a material is mainly applicable to a resin molded article such as a fiber, a coating film, a film, a sheet, a foam, and a rubber. Specific methods include injection molding, extrusion molding, melt spinning, solution spinning and coating using a resin mixed with the moisture absorptive and desorptive polymer of the present invention.

The type of the resin constituting the resin molding to which this method can be applied is not particularly limited and examples thereof include phenol resin, epoxy resin, melamine resin, urea resin, unsaturated polyester resin, alkyd resin, urethane resin, Thermoplastic resins such as polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyvinyl acetate, polytetrafluoroethylene, ABS resin, AS resin and acrylic resin, thermoplastic resins such as polyamide, , Engineering plastics such as polycarbonate, modified polyphenylene ether, polystyrene terephthalate, polyethylene terephthalate, and cyclic polyolefin, and natural resins.

As the resin constituting the resin molded article, it is preferable that the permeability of water vapor is high. In the resin molded article, since the contact between the moisture absorptive and desorptive polymer of the present invention and water vapor is limited, the moisture absorptive and desorptive ability inherent to the moisture absorptive and desorptive polymer of the present invention may not be sufficiently exhibited. However, by employing a resin having a high permeability to water vapor, the moisture absorptive and desorptive polymer of the present invention is likely to be in contact with water vapor, and moisture absorptive and desorptive performance can be more easily exerted. Further, in this case, the moisture absorptive and desorptive property of the moisture absorptive and desorptive polymer of the present invention is added to the water vapor permeability inherent in the resin, whereby a resin molded article having a better moisture permeability can be obtained.

In addition, when the constituent component of the resin has a functional group or a structure capable of forming a covalent bond with the hydroxyl group or forming a hydrogen bond or an ionic bond with the hydroxyl group, as described above, the moisture absorptive and desorptive polymer The deterioration of the water resistance caused by the addition can be suppressed. Specific examples of the functional group or structure capable of obtaining such an effect include an isocyanate group, an ester group, an amide group, a halogen group, an epoxy group, a carboxyl group, a hydroxyl group, an amino group and a thiol group. Among them, a functional group having an electrophilic property such as an isocyanate group, an ester group, an amide group, a halogen group or an epoxy group reacts with a hydroxyl group to form a covalent bond and is firmly bonded to the resin molding, The effect of suppressing the deterioration of the water resistance is also increased.

From the viewpoint of suppressing lowering of the water vapor permeability and water resistance described above, a suitable resin is a urethane resin containing a constituent component having a large number of hydrophilic structures such as a urethane bond or the like and having an isocyanate group.

Next, with respect to the method of directly fixing to the material, from the viewpoint of suppressing the drop of the moisture absorptive and desorptive polymer from the material, the surface of the material is reacted with a hydroxyl group to form a functional group capable of forming a covalent bond, Can be suitably applied to a material having a functional group capable of forming a functional group. Among them, a material having an electrophilic group capable of forming a covalent bond such as an isocyanate group, an ester group, an amide group, a halogen group or an epoxy group is suitable, and a material having an isocyanate group is particularly suitable.

Specific examples of the method include a method of impregnating or applying a slurry or emulsion of a particulate moisture absorptive and desorptive polymer to a paper, a nonwoven fabric, a yarn, a fabric, a knitted fabric, a sheet or a foam. In the case of paper, a method of mixing granular or fibrous moisture absorptive and desorptive polymers in the production process, or in the case of nonwoven fabrics, is added in the manufacturing process, and the fibers are fixed to thermally adhesive fibers constituting the nonwoven fabric can do.

The method of fixing the moisture absorptive and desorptive polymer of the present invention to a material by a binder resin can be applied to various materials including the above-mentioned materials. Here, the binder resin to be used may be suitably selected in accordance with the material, and examples of the thermosetting resin and the thermoplastic resin may be mentioned. Also, as in the case of the above-described resin molded article, it is preferable that the resin used as the binder resin has a high water vapor permeability. From the viewpoint of suppressing the deterioration of the water resistance and from the viewpoint of further suppressing the detachment, it is preferable to have a functional group capable of forming a hydrogen bond or an ionic bond with a functional group or a hydroxyl group capable of forming a covalent bond by reacting with a hydroxyl group Among them, a binder resin having an electrophilic group capable of forming a covalent bond such as an isocyanate group, an ester group, an amide group, a halogen group or an epoxy group is preferable. And a urethane resin can be suitably used as a binder resin that satisfies all of these preferred embodiments.

Specific examples of the method include a method of applying or spraying a binder resin solution containing the moisture absorptive and desorptive polymer of the present invention onto a material such as a fiber, a paper, a nonwoven fabric, a thread, a fabric, a knitted fabric, a skin, a film, a sheet, a foam, And a method of immersing these materials in such a binder resin solution.

The amount of the moisture absorptive and desorptive polymer to be added to the material of the present invention may be suitably set in accordance with the required moisture absorptive and desorptive performance, but in general, it is appropriate to set the amount in the range of 1 to 80% by weight of the material. When the amount exceeds 80% by weight, the moisture absorptive and desorptive polymer tends to drop off, or the deformation due to water swelling increases. In particular, it is difficult to form the moisture absorptive and desorptive polymer when it is mixed with the resin molding. In addition, when the content is less than 1% by weight, the effect of improving the moisture absorptive and desorptive performance is often not revealed.

Further, since the moisture absorptive and desorptive polymer of the present invention forms a large number of chemical bonds with the material, and consequently, the material components are crosslinked with each other, the effect of improving the mechanical strength of the material can be expected.

(Example)

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples. The parts and percentages in the examples are expressed by weight unless otherwise specified. First, an evaluation method of each characteristic will be described.

<Saturated moisture absorption rate>

About 1.0 g of the sample particles were dried in a hot-air drier at 105 ° C for 16 hours to measure the weight (Wds [g]), and then the sample particles were left in a thermostatic hygrostat with a temperature of 20 ° C and a relative humidity of 65% RH for 24 hours , And the weight of the moisture-absorbed sample particles was measured (Wws [g]). Based on the above results, it was calculated by the following equation.

Saturated moisture absorption rate [%] = {(Wws-Wds) / Wds} 100

<Average Particle Diameter>

The average particle diameter of the particles was measured by using a laser diffraction particle size distribution analyzer &quot; SALD2000 &quot; manufactured by Shimadzu Seisakusho Co., Ltd., using water as a dispersion medium, and the result was expressed as volume basis, and the median diameter was taken as the average particle diameter.

<Fisheries capacity>

The amount of hydroxyl groups other than that in Example 6 was first analyzed by elemental analysis of the sample before hydrolysis after polymerization and the oxygen atom weight ratio and nitrogen content were measured to find that the vinyl acetate unit content (A [mmol / g]) and acrylonitrile unit content (B [mmol / g]). Thereafter, it was confirmed that the vinyl acetate unit and the acrylonitrile unit were completely hydrolyzed by the infrared spectroscopic measurement of the sample after the hydrolysis, and it was confirmed that the vinyl acetate unit and the acrylonitrile unit were completely hydrolyzed by the hydroxyl group (vinyl alcohol unit) and the salt carboxyl group (sodium acrylate unit) And the change in weight is obtained from these values.

Change in Weight of Acetic Acid Vinyl Unit Per 1 g of Raw Material Polymer [g]

= 0.044A-0.086A = -0.042A

Weight change of acrylonitrile unit per gram of raw polymer [g]

= 0.094B-0.053B = 0.041B}

Hydroxyl value [mmol / g] = A / (1-0.042A + 0.041B)

&Lt; Amount of salt type carboxyl group &

The amount of the salt-type carboxyl group was obtained by subtracting the amount of the H-type carboxyl group from the total amount of the carboxyl group. First, 1 g of a sample sufficiently dried (X [g]) was added with 200 ml of water, and a 1N hydrochloric acid aqueous solution was added thereto while being heated to 50 ° C to adjust the pH to 2 to convert all of the carboxyl groups contained in the sample into H Carboxyl group, and then a titration curve was determined with a 0.1 N aqueous sodium hydroxide solution according to the conventional method. From this titration curve, the consumption amount (Y [ml]) of aqueous sodium hydroxide consumed in the H-type carboxyl group was determined, and the total amount of carboxyl groups contained in the sample was calculated by the following formula.

Amount of total carboxyl groups [mmol / g] = 0.1 Y / X

Separately, a titration curve was similarly obtained without adjustment to pH 2 by the addition of a 1N hydrochloric acid aqueous solution during the above-described measurement of the total amount of carboxyl groups, and the amount of the H-type carboxyl group contained in the sample was obtained. From these results, the amount of salt-type carboxyl groups was calculated by the following formula.

Amount of salt-type carboxyl group [mmol / g] = (amount of total carboxyl group) - (amount of amount of H form carboxyl group)

<Water resistance>

6.5 g of a polyisocyanate (Bernok DN-980K, manufactured by DIC), 5 g of a sample particle and 23.5 g of a polyol (Acridic A-801-P, manufactured by DIC) And dried at 130 DEG C for 30 minutes. The water resistance evaluation was performed by immersing the sample in water for 10 minutes, then wiping off the moisture on the surface, and visually judging whether or not whitening was visible in the coating portion.

&Lt; Hygroscopicity &lt;

The hygroscopic occurrence rate is calculated from the saturated moisture absorption rate A [%], the content of the sample particles B (g / m ² ) and the moisture absorption amount C (g / m ² ) in the above water resistance evaluation sample, (D [g / m &lt; ² &gt;]) of the blank sample obtained by applying the evaluation sample and sample particles in the same manner as described above except that no sample particles and sample particles were added. The moisture absorptions C and D were measured by the same method as the above-described saturated moisture absorptive rate.

Hygroscopic Expression Rate (%) = [(C-D) / B x 100] / A x 100

<Breathability>

40 parts of the sample particles and 100 parts of Yuretene resin (Superflex (registered trademark) E-4800, Daiichi Kyoei Co., Ltd.) were mixed and coated on a nylon mesh (200 mesh) And dried at room temperature. The moisture permeability of the obtained coated cloth is measured based on JIS L 1099 (method A-1).

[Example 1]

74 parts of acrylonitrile, 1 part of vinyl acetate and 25 parts of divinylbenzene was added to 300 parts of an aqueous solution containing 0.5 parts of ammonium persulfate, and then 0.6 part of sodium pyruvate was added to the polymerization vessel equipped with a stirrer At 65 캜 for 2 hours. The obtained polymer is filtered and washed with water. Subsequently, 100 parts of this polymer was added to 567 parts of a 10% aqueous sodium hydroxide solution, and hydrolysis was carried out at 95 DEG C for 48 hours. Then, the resulting polymer was filtered and washed with water to obtain a hygroscopic fine particle 1. The evaluation results of these particles are shown in Table 1, and the water resistance was good. In addition, the hygroscopicity expression ratio of the sample used in the water resistance evaluation was 90.7% or more.

The hygroscopic fine particles 1 were pulverized to give an average particle diameter of 5 탆. The moisture permeability of the sample was measured by the above-mentioned method and found to be 91.0 g / m ² h. This is higher than the measured moisture permeability of 45.8 g / m ² · h except that the hygroscopic fine particles 1 are not added, and shows the effect of improving moisture permeability of the moisture absorptive and desorptive polymer of the present invention.

[Comparative Example 1]

Hygroscopic fine particles 2 were obtained in the same manner as in Example 1, except that 75 parts of acrylonitrile and 25 parts of divinylbenzene were used as the monomer mixture liquids. The evaluation results of these particles are shown in Table 1, and they were whitened by immersion in water.

[Example 2]

Hygroscopic fine particles 3 were obtained in the same manner as in Example 1 except that the monomer mixture liquid of 64 parts of acrylonitrile, 1 part of vinyl acetate and 35 parts of divinylbenzene was used. The evaluation results of these particles are shown in Table 1, and the water resistance was good.

[Comparative Example 2]

Hygroscopic fine particles 4 were obtained in the same manner as in Example 1 except that the monomer mixture liquid of 65 parts of acrylonitrile and 35 parts of divinylbenzene was used. The evaluation results of these particles are shown in Table 1, and they were whitened by immersion in water.

[Example 3]

Hygroscopic fine particles 5 were obtained in the same manner as in Example 1, except that 56.7 parts of acrylonitrile, 8.3 parts of vinyl acetate and 35 parts of divinylbenzene were used as the monomer mixture solution in Example 1. The evaluation results of these particles are shown in Table 1, and the water resistance was good.

[Example 4]

Hygroscopic fine particles 6 were obtained in the same manner as in Example 1, except that the monomer mixture liquid of 5 parts of acrylonitrile, 60 parts of vinyl acetate and 35 parts of divinylbenzene was used. The evaluation results of these particles are shown in Table 1, and the water resistance was good.

[Example 5]

Hygroscopic fine particles 7 were obtained in the same manner as in Example 1, except that the monomer mixture liquid of 10 parts of acrylonitrile, 65 parts of vinyl acetate and 25 parts of divinylbenzene was used. The evaluation results of these particles are shown in Table 1, and the water resistance was good.

[Example 6]

A monomer mixture consisting of 10 parts of methacrylic acid, 3 parts of 4-hydroxyl butyl acrylate, 62 parts of acrylonitrile and 25 parts of divinylbenzene was added to 300 parts of an aqueous solution containing 0.5 parts of ammonium persulfate, And 0.6 part of sodium sulfate, and the mixture is polymerized at 65 DEG C for 2 hours in a polymerization vessel equipped with a stirrer. The obtained polymer is filtered and washed with water. The cleaning liquid was analyzed by gas chromatography to determine the amount of methacrylic acid and 4-hydroxylbutylacrylate introduced into the polymer. Subsequently, 100 parts of the polymer was added to 567 parts of an aqueous 2% sodium carbonate solution, and the neutralization reaction of the carboxyl groups was carried out at 30 DEG C for 4 hours. Then, the obtained polymer was filtered and washed with water to obtain a hygroscopic fine particle 8. The evaluation results of these particles are shown in Table 1, and the water resistance was good. With respect to the amount of hydroxyl groups at this time, the weight change by a theoretical neutralization reaction of the methacrylic acid unit (A [mmol / g]) obtained by the gas chromatography analysis and the weight change by the 4-hydro (B [mmol / g]) of the butyl acrylate unit.

Change in weight of methacrylic acid unit per gram of raw polymer [g]

= 0.108A-0.086A = 0.022A

Hydroxyl value [mmol / g] = B / (1 + 0.022A)

[Example 7]

5 g of hygroscopic fine particles 1, 27.8 g of bisphenol A diglycidyl ether, 2.2 g of dicyandiamide, and 0.8 g of dimethyl urea were coated on a PET film with a bar coater and then dried at 120 캜 for 30 minutes, A sample added to the hygroscopic fine particles 1 in an epoxy resin is prepared. Using these measurement samples, the water resistance and the hygroscopicity expression ratio were evaluated in the same manner as described above. This sample was not whitened even after immersion in water, and exhibited good water resistance. The hygroscopicity-inducing rate was also good at 85.1%.

[Referential Example 1]

1 part of p-cyanoisocyanate (Wako Pure Chemical Industries, Ltd.) was dissolved in 50 parts of methyl ethyl ketone. Two parts of the hygroscopic fine particles 1 were added and stirred at 80 ° C for 12 hours. The particles were then filtered and washed three times with acetone , And dried at 50 DEG C for 12 hours to obtain fine particles 9. [ The infrared absorption spectrum of the particles is shown in Fig. 2, and the infrared absorption spectrum of the hygroscopic fine particle 1 is shown in Fig. 2 shows absorption at 2241 cm ^-1 derived from the cyano group not shown in FIG. 1 and at 1739 cm ^-1 representing urethane bond. That is, in the fine particles 9 obtained by reacting the hygroscopic fine particles 1 with phenyl p-cyanoisocyanate, urethane bonds and cyano groups are introduced. In this point, the hydroxyl groups of the hygroscopic fine particles 1 react with the isocyanate groups to form covalent bonds Are formed.

[Reference Example 2]

In the same manner as in Reference Example 1 except that the hygroscopic fine particles 2 were used instead of the hygroscopic fine particles 1, operations were carried out in the same manner to obtain fine particles 10. The infrared absorption spectrum of this particle is shown in Fig. 4, and the infrared absorption spectrum of the hygroscopic fine particle 2 is shown in Fig. It is understood that the hygroscopic fine particles 2 having no hydroxyl group do not react with the isocyanate groups.

The moisture absorptive and desorptive polymer and the material of the present invention are excellent in moisture absorptive and desorptive performance and moisture permeability in various fields such as fiber, textile processed product, medical product, sheet, paper, nonwoven fabric, film, binder, paint, adhesive, sensor, resin, Can be widely used as a material capable of imparting heat resistance.

Claims (8)

Wherein the polymer is a vinyl-based polymer containing 1-7 mmol / g of a salt-type carboxyl group and 0.01 to 1 mmol / g of a hydroxyl group and having a crosslinking structure. The positive resist composition as claimed in claim 1, which comprises a vinyl monomer having a structure capable of forming a salt-type carboxyl group by hydrolysis, a vinyl monomer having a structure capable of forming a hydroxyl group by hydrolysis and a monomer containing a crosslinkable vinyl monomer Wherein the copolymer is obtained by hydrolyzing a copolymer obtained by polymerizing the mixture. The moisture absorptive and desorptive polymer according to claim 1, wherein the form is particulate. A material containing the moisture absorptive and desorptive polymer according to any one of claims 1 to 3. A material obtained by molding a resin to which the moisture absorptive and desorptive polymer according to claim 1 is added. A material to which the moisture absorptive and desorptive polymer according to claim 1 is added together with a binder resin. The material according to claim 5 or 6, wherein the resin has an electrophilic functional group. The material according to claim 5 or 6, wherein the resin is a urethane resin.

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