JP3953638B2 - Aldehyde adsorbent - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an aldehyde adsorbent, and more particularly to a powdery or fibrous aldehyde adsorbent composed of an acetoacetyl group-containing vinyl alcohol resin that adsorbs formaldehyde generated from various substrates.
[0002]
[Prior art]
In recent years, formaldehyde has been used in a large amount as a raw material for low-molecular synthetic materials and polymer resins. Resins obtained from these, such as phenol-formaldehyde resins, melamine-formaldehyde resins, urea-formaldehyde resins, guanamine-formaldehyde resins, are widely used in adhesive processing, molding processing, paper processing, fiber processing, paints, decorative boards, etc. Used for applications. However, when manufacturing such resins or processing the resins, there is often a problem that formaldehyde is slightly dissipated in the atmosphere and an irritating odor drifts, and various processing obtained using such resins. Products also tend to generate formaldehyde, which is a problem.
[0003]
Further, formaldehyde is contained in wood that does not use an adhesive made of the above resin, and it is known that a trace amount of formaldehyde is diffused into the air from such wood. Formaldehyde is harmful to the human body, and if it is present in the air at 10 ppm or more, it cannot withstand the pungent odor, and it is closely related to processed products and everyday life, such as building materials, equipment, clothing, automobiles, sanitary materials, miscellaneous goods, There is a strong demand for a method for reducing formaldehyde generated from foods and the like.
[0004]
As one of such measures, a formaldehyde scavenger is used for general purposes. Conventionally known as formaldehyde scavengers are urea, thiourea, ethylene urea, dicyandiamide, glyoxal monoureine, etc., either processed in the same bath as the resin containing formaldehyde, or after processing with a resin containing formaldehyde, There is a method of attaching a formaldehyde supplement by spraying or the like.
[0005]
[Problems to be solved by the invention]
However, as a result of detailed investigations by the present inventors, it has been found that the above method is still not satisfactory in terms of deodorizing ability with respect to formaldehyde, particularly in terms of the initial deodorizing rate. Therefore, an object of the present invention is to provide an aldehyde adsorbent that efficiently reduces formaldehyde. As a measure for reducing the formaldehyde, JP-A-9-100302 proposes a method of incorporating a compound having a —NH— bond such as urea into a polyvinyl alcohol film as an aldehyde deodorant, As polyvinyl alcohol used for such a film, an acetoacetyl group-containing polyvinyl alcohol resin is not described. JP-A-6-33035 proposes that a polyalkylene glycol diester (oligomer having an acetoacetyl group at the end) is used as a formaldehyde scavenger. In such a scavenger, It is still not satisfying and uses are limited.
[0006]
[Means for Solving the Problems]
Therefore, as a result of intensive studies in view of such circumstances, the present inventors have found that a powdery or fibrous aldehyde adsorbent composed of an acetoacetyl group-containing vinyl alcohol resin is excellent in reducing aldehydes such as formaldehyde. As a result, the present invention has been completed. In the present invention, acetoacetyl group-containing polyvinyl alcohol-based resin is preferably a acetoacetyl group-containing Yupo polyvinyl alcohol resin.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be specifically described. Adsorbents of the present invention, Ri vinyl alcohol resin Tona having an acetoacetyl group, and acetoacetyl group-containing Yupo polyvinyl alcohol resin as Particularly preferable.
[0008]
An acetoacetyl group-containing polyvinyl alcohol resin includes a method of reacting a polyvinyl alcohol resin with diketene, a method of transesterifying a polyvinyl alcohol resin with acetoacetate ester, vinyl acetate, vinyl acetoacetate and allyl acetoacetate. Any method such as a copolymerization method may be used. However, the production process is simple, and a high quality acetoacetyl group-containing polyvinyl alcohol resin is obtained. From this, a polyvinyl alcohol resin and diketene are reacted. It is preferable to manufacture by. As a method of reacting the polyvinyl alcohol resin and the diketene, the polyvinyl alcohol resin and the gaseous or liquid diketene may be directly reacted, or the organic acid is preliminarily adsorbed and occluded in the polyvinyl alcohol resin. A method of spraying and reacting liquid or gaseous diketene in a gas atmosphere, or spraying and reacting a mixture of an organic acid and liquid diketene to a polyvinyl alcohol resin is used.
[0009]
Examples of the polyvinyl alcohol resin include a polyvinyl alcohol resin obtained by saponifying a lower alcohol solution of polyvinyl acetate with a saponification catalyst such as an alkali, a derivative thereof, and a monomer copolymerizable with vinyl acetate. A saponified product of a copolymer with vinyl acetate is exemplified.
[0010]
Examples of monomers include olefins such as ethylene, propylene, isobutylene, α-octene, α-dodecene, α-octadodecene, acrylic acid, methacrylic acid, crotonic acid, maleic acid, maleic anhydride, itaconic acid, and the like. Unsaturated acids or salts thereof, mono- or dialkyl esters, nitriles such as acrylonitrile and methacrylonitrile, amides such as acrylamide and methacrylamide, olefin sulfonic acids such as ethylene sulfonic acid, allyl sulfonic acid and methallyl sulfonic acid, or Its salts, alkyl vinyl ethers, N-acrylamidomethyltrimethylammonium chloride, allyltrimethylammonium chloride, dimethyldiallylammonium chloride, dimethylallyl vinyl ketone, N-vinyl pyro Don, vinyl chloride, vinylidene chloride, polyoxyethylene (meth) allyl ether, polyoxyalkylene (meth) allyl ether such as polyoxypropylene (meth) allyl ether, polyoxyethylene (meth) acrylate, polyoxypropylene (meth) Polyoxyalkylene (meth) acrylates such as acrylate, polyoxyalkylene (meth) acrylamides such as polyoxyethylene (meth) acrylamide, polyoxypropylene (meth) acrylamide, and polyoxyethylene (1- (meth) acrylamide-1,1 -Dimethylpropyl) ester, polyoxyethylene vinyl ether, polyoxypropylene vinyl ether, polyoxyethylene allylamine, polyoxypropylene allylamine, polyoxyethylene vinyl Triethanolamine, a copolymer saponified product of a polyoxypropylene vinyl amine.
[0011]
As a reaction apparatus for containing an acetoacetyl group, any apparatus capable of heating and equipped with a stirrer is sufficient. For example, a kneader, a Henschel mixer, a ribbon blender, other various blenders, and a stirring / drying apparatus can be used.
[0012]
The acetoacetyl group-containing polyvinyl alcohol resin obtained as described above has an average degree of polymerization of 100 to 4000, preferably 200 to 3000, more preferably 250 to 2800, and a degree of saponification of 65 to 100 mol%, preferably 68 to 100 mol. %, More preferably 70 to 100 mol%. The acetoacetyl group content is desirably 0.5 to 20 mol%, preferably 0.5 to 15 mol%, more preferably 2 to 10 mol%. If the acetoacetyl group content is less than 0.5 mol%, the deodorizing ability of formaldehyde is insufficient. On the other hand, if it exceeds 20 mol%, the acetoacetyl group-containing polyvinyl alcohol resin is insolubilized due to a cross-linking reaction between molecular chains. It is not preferable.
[0013]
The saponification degree is calculated by a saponification degree measuring method according to JISK6726 by chemical analysis. (The acetoacetyl group is saponified similarly to the acetyl group.)
The acetoacetyl group content was determined by ¹ H-NMR measurement (270 MHz) (solvent; d-DMSO), with an integrated intensity I _CH3 (CH _{3 of} acetoacetyl group) of 2.18 ppm, and 1.3 to 1.6 ppm. The integral intensity I _CH2 in the range (CH _{2 of} polyvinyl alcohol) is calculated from the following formula (I).
[Expression 1]
2I _CH3 × 100 / 3I _CH2 (I)
[0014]
Also, saponified ethylene-vinyl acetate copolymer (abbreviated as EVOH) can contain an acetoacetyl group in the same manner as described above, and is effective as an aldehyde adsorbent. The ethylene content of EVOH is preferably 3 to 65 mol%, particularly 5 to 50 mol%, and the saponification degree is preferably 90 to 100 mol%, particularly 97 to 100 mol%. The acetoacetyl group content is the same as described above.
[0015]
In the present invention, the acetoacetyl group-containing vinyl alcohol resin as described above is very effective as an aldehyde adsorbent for a resin or substrate containing formaldehyde, and exhibits an excellent effect in reducing formaldehyde.
[0016]
In the present invention, powdery or fibrous aldehyde adsorbent consisting of the acetoacetyl group-containing polyvinyl alcohol-based resin, a known deodorant, for example phosphorus oxide, phosphate containing silver oxide 2 wt% or more It is also possible to contain glass powder, alkylene diamine, polyalkylene diamine, ferric chloride, chromium chloride, manganese chloride, nickel chloride, copper chloride, iron chloride and the like. Among the known deodorants, when phosphoric acid glass powder, alkylenediamine, and polyalkylenediamine are used in combination, 0.1 to 20 parts by weight, preferably 0, per 100 parts by weight of the acetoacetyl group-containing polymer compound It is appropriate to add 3 to 15 parts by weight.
[0017]
In addition, when a metal ion such as ferric chloride, chromium chloride, manganese chloride, nickel chloride, copper chloride, or iron chloride is added, it is 2 with respect to the acetoacetyl group (and hydroxyl group) of the acetoacetyl group-containing polymer compound. It is appropriate to add ~ 100 mol%, preferably 5-80 mol%. The metal ion forms a chelate with an acetoacetyl group or a hydroxyl group and uniformly disperses, thereby effectively acting on malodors (ammonia, hydrogen sulfide, trimethylamine, etc.) other than aldehyde compounds.
[0018]
The aldehyde adsorbent of the present invention is obtained by, for example, mixing the above acetoacetyl group-containing vinyl alcohol resin with water or an organic solvent such as dimethyl sulfoxide, dimethylformamide, dimethylacetamide, ethylene glycol, glycerin, diglycerin, hexafluoroisopropanol or the like. dissolved in a liquid or sol Te, or by fibrous by gel spinning, it can also be in a powder state practical use.
[0019]
In addition, when the aldehyde adsorbent of the present invention is used, formaldehyde can be reduced as a powder or as a fiber (woven fabric or nonwoven fabric). In particular, the fibrous sheet of the nonwoven fabric or the like because of large surface area, it is possible to draw a higher deodorizing ability of the deodorizing agent, yet various applications since it is flexible, can be used in place.
[0020]
Specific use cases, lay nonwoven fabric comprising the adsorbent of A) the present invention under the flooring, b) used as a rug, such as drawers or closet furniture, c) are used for the packaging of textile products , d) a refrigerator, placing the molded body containing the adsorbent of the present invention in a freezer, combination and deodorant with activated carbon in e) d) f) air purifier, cooler, a filter such as a heater G ) The adsorbent of the present invention is mixed with a fragrance in a room to form a molded body and used as a fragrance or a deodorant , but is not limited thereto. .
[0021]
Thus, the aldehyde adsorbent of the present invention can be used in any form and exhibits a very excellent effect in reducing formaldehyde-containing objects or formaldehyde generated from the substrate.
[0022]
【Example】
Hereinafter, the present invention will be specifically described with reference to examples. In the examples, “parts” and “%” mean weight basis unless otherwise specified. The following (a-1) to (a- 2 ) were used as the acetoacetyl group-containing polyvinyl alcohol resin.
(A- 1 ): acetoacetyl group content 5 mol%, polymerization degree 1400, saponification degree 94 mol% acetoacetyl group-containing polyvinyl alcohol resin (a- 2 ); acetoacetyl group content 6 mol%, polymerization Acetoacetyl group-containing polyvinyl alcohol resin having a degree of saponification of 1700 and a saponification degree of 93.5 mol%
Unless otherwise specified, the amount of free formalin was measured as follows. The air to be tested is passed through a scrubber containing 10 cc of 1% sodium acid sulfite at a rate of 1-3 liters per minute. When the wash is complete, transfer the solution and wash to a 250 or 300 cc Erlenmeyer flask. When washing at a rate of 28 liters per minute, use a large washer containing 100 cc of acidic sodium sulfite and use a multiple of 10 cc of wash for analysis. The solution to be analyzed is titrated with about 0.1N iodine to the dark blue end point using starch as an indicator. Excess iodine is decomposed with 0.05N thiosulfate and then titrated with 0.01N iodine to a faint blue color. If acetone is present in the air being tested, add 2 cc of 5% sodium bicarbonate and decompose the sulfite liberated by combining with acetone by adding 0.01 N iodine.
[0024]
Dissolve 80 g of sodium carbonate in 500 g of water and add 25 cc of sodium carbonate buffer prepared by adding 20 cc of glacial acetic acid. When the addition is complete, titrate with 0.01N iodine to a faint blue endpoint. When the titrant is 1 cc or less, a blank test is performed on 10 cc of 1% acidic sulfite, and the result is subtracted from the sample titrant. Results are calculated based on 1.0 cc of 0.01N iodine equivalent to 0.15 mg of formaldehyde.
[0025]
Example 1
After pulverizing the acetoacetyl group-containing polyvinyl alcohol resin (a- 1 ) so as to be 100 μm or less, 8 g of the powdery (a- 1 ) was put into a formalin-treated cloth 300 g (free formalin amount 300 ppm). Placed in a 3 l conical Erlenmeyer flask. And after leaving still at 40 degreeC x 65% RH for 2 weeks, when the amount of free formalins remaining on cloth was analyzed, the amount of free formalins was reduced to 20 ppm. The amount of free formalin was measured according to JISL1041 (acetylacetone method (method B)).
[0026]
Comparative Example 1
In Example 1 , an acetoacetyl group-containing polyvinyl alcohol resin (a- 1 ) was changed to a polyvinyl alcohol resin (polymerization degree 1700, saponification degree 98 mol%, trade name: Gohsenol AH-17, Nippon Synthetic Chemical Industry Co., Ltd.) The procedure was the same as in Example 1 except that the amount of free formalin was 270 ppm.
[0027]
Example 2
The acetoacetyl group-containing polyvinyl alcohol resin (a- 2 ) was dissolved in DMSO (dimethyl sulfoxide) at 90 ° C. under a nitrogen atmosphere, and the spinning dope was passed through a nozzle having a pore diameter of 0.08 m and a pore number of 500, and methanol / Immersion spinning was carried out in a solidified solution of 20 ° C. consisting of DMSO = 8/2. The solidified system was wet-drawn 5.0 times, immersed in a methanol solution, DMSO was extracted and washed, a mineral oil-based oil agent was applied, and a filament of 520 dr / 500 f was obtained. This fiber was mechanically crimped, cut into 38 mm, and stapled. This was applied to a card, and a web having a basis weight of 12 g / m 2 was produced by a conventional method. The web was laid under a flooring material (4 m × 4 m), and the amount of free formalin after 7 days was measured in a room where the atmospheric concentration of free formalin was 8 ppm (indoor environment: 23 ° C. × 40% RH). It was 0.1 ppm or less .
[0028]
Example 3
500 parts of ethylene-vinyl acetate copolymer saponified powder (ethylene content 38 mol%, polymerization degree 800, particle size 100 mesh or less) containing 0.3% sodium acetate was charged into a kneader and stirred at a rotation speed of 20 rpm. After the temperature was raised to 60 ° C., a mixture of 740 parts of diketene and 80 parts of acetic acid was added by spraying over 30 minutes. When reacted at 60 ° C. for 30 minutes, a saponified acetoacetyl group-containing ethylene-vinyl acetate copolymer having an acetoacetyl group content of 6 mol% was obtained. 10 g of the acetoacetyl group-containing ethylene-vinyl acetate copolymer saponified product was placed in a 3 l confined conical flask containing 300 g of a formalin-treated cloth (free formalin amount: 300 ppm). Then, after leaving for 2 weeks at 65 ° C. at 40 ° C., the amount of free formalin remaining on the cloth was measured and found to decrease between 12 ppm. The amount of free formalin was measured according to JISL1041 (acetylacetone method (method B)).
[0029]
【The invention's effect】
Aldehyde adsorbent of the present invention, a powder, fibrous, Furthermore, since growth form, interior materials, wallpaper, can be used with equal any form, consisting of acetoacetyl group-containing Yubi alkenyl alcohol-based resin, containing formaldehyde It is very effective in reducing the formaldehyde generated from the target object or substrate.

Claims (2)

Powdered or fibrous aldehyde adsorbent consisting of an acetoacetyl group-containing polyvinyl alcohol-based resin. Acetoacetyl group-containing polyvinyl alcohol-based resin, an aldehyde adsorbent according to claim 1, characterized in that an acetoacetyl group-containing polyvinyl alcohol-based resin.