JPH09176947A - Binder for nonwoven cloth - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provided a binder for nonwoven cloth having suitable flexibility and extremely slight deterioration of tensile strength at high temperature by mixing an aqueous emulsion with a heatcurable amino resin and an acrylamide- based polymer. SOLUTION: This binder for nonwoven cloth is obtained by mixing the below- mentioned component A, a heat-curable resin such as melamine resin and an aqueous solution of a component C as shown below. The copolymer aqueous emulsion A having 50-90 deg.C glass transition temperature is formed by emulsion polymerizing 1-30wt.% of an amide group-containing ethylenic unsaturated monomer such as acrylamide with 99-70wt.% of another ethylenic unsaturated monomer copolymerizable with the amide group-containing monomer such as methyl acrylate. The acrylamide-based polymer C having 50×10<4> -1,000×10<4> weight-average molecular weight and <=500poise Brookfield viscosity of an aqueous solution at a polymer concentration of 22-60wt.% is obtained by copolymerizing acrylamide with one or more than two kind of vinyl compound selected from among a vinyl compound expressed by the formula (R is H or a lower alkyl, (n) is an integer of 1-8), such as methacryl sulfonic acid soda and/or its salt.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-woven fabric binder, and more particularly to a non-woven fabric binder for imparting excellent hot tensile strength to a non-woven fabric for asphalt impregnation used for building waterproofing.

[0002]

2. Description of the Related Art Asphalt-impregnated non-woven fabrics, which are currently mainly used for waterproofing buildings, are obtained by impregnating a sheet-like web of various fibers with a binder and then heat-treating it.
It is produced by imparting normal tensile strength, normal tear resistance, normal flexibility, and hot tensile strength to a nonwoven fabric, and further impregnating this nonwoven fabric with asphalt melted at high temperature. As described above, since the non-woven fabric is impregnated with the asphalt melted at a high temperature, one of the most important performances required for the non-woven fabric before the asphalt impregnation is hot tensile strength. Therefore, a thermosetting resin has been used as a binder, in particular, as a means for imparting a tensile strength when heated.

[0003]

However, since it has tensile strength at the time of heating but lacks flexibility in the normal state and at the time of heating, it is attempted to impart flexibility by using an aqueous emulsion together. Instead, the adverse effect that the tensile strength at the time of heating is lowered occurs. In view of such circumstances, the present inventors have previously used, in Japanese Patent Application No. 05-013264, a specific aqueous emulsion and a thermosetting amino resin in combination as a binder for a non-woven fabric whose tensile strength at the time of heating does not decrease. I'm making a proposal. Although it was able to extremely suppress the decrease in tensile strength under heat, the normal tensile strength and the normal tear resistance were not always satisfactory, and overall it was still insufficient. Therefore, in the industry, it is desired to develop a comprehensively excellent binder as a non-woven fabric binder.

[0004]

Means for Solving the Problems The inventors of the present invention have made earnest studies in view of the above-mentioned circumstances, and as a result, a conventional thermosetting amino resin and an aqueous emulsion were used in combination with a specific acrylamide polymer aqueous solution. By mixing
A comprehensively balanced binder composition for a non-woven fabric was found, and the present invention was completed.

That is, the present invention is a non-woven fabric binder comprising an aqueous emulsion (A), a thermosetting amino resin (B) and an aqueous acrylamide polymer solution (C), wherein the acrylamide polymer aqueous solution (C) has a polymer concentration. 22-60% by weight, Brookfield viscosity 500
ps or less and weight average molecular weight of 500,000 to 1,000
In addition, the present invention relates to a nonwoven fabric binder containing, as a copolymerization component, one or more vinyl compounds selected from the vinyl compound represented by the following general formula (1) and / or salts thereof.

The general formula (1) (In the formula, R is a hydrogen atom or a lower alkyl group, and n is 1 to 8
Integer)

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below. The aqueous emulsion (A) used in the present invention contains 1 to 30% by weight of an amide group-containing ethylenically unsaturated monomer.
And an aqueous emulsion obtained by emulsion-polymerizing 99 to 70% by weight of another ethylenically unsaturated monomer copolymerizable therewith, and having a glass transition temperature (Tg) of 50 to 90 ° C. It can be obtained by the known emulsion polymerization method shown.

That is, a mixture of an ethylenically unsaturated monomer containing an amide group described below and another ethylenically unsaturated monomer is added dropwise to an appropriate amount of water containing a small amount of an emulsifier and a polymerization initiator. Then, the unsaturated monomer is emulsion polymerized.

Examples of the amide group-containing ethylenically unsaturated monomer used in the present invention include acrylamide, methacrylamide, N-methylol acrylamide, N-methylol methacrylamide, and N-methylol crotonamide. One kind or two or more kinds of is used. Of these, methacrylamide is preferably used.

Other ethylenically unsaturated monomers copolymerizable with the amide group-containing ethylenically unsaturated monomer used in the present invention include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate and propyl. Acrylic alkyl esters and methacrylic acid alkyl esters exemplified by acrylate, propyl methacrylate, butyl acrylate, butyl methacrylate, pentyl acrylate, pentyl methacrylate and the like; ethylenic exemplified by styrene, α-methylstyrene, vinyltoluene, chlorostyrene, etc. Unsaturated aromatic monomers; vinyl esters such as vinyl acetate and vinyl propionate; ethylenically unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, maleic acid and their anhydrides; Ethylenically unsaturated dicarboxylic acids such as acid and itaconic acid; Hydroxyalkyl esters of ethylenically unsaturated carboxylic acids such as 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate and 2-hydroxyethyl methacrylate; glycidyl acrylate and glycidyl methacrylate Examples thereof include glycidyl ester of ethylenically unsaturated carboxylic acid; nitriles such as acrylonitrile and methacrylonitrile, and one or more of these are used.

The ratio of the total amount of the above-mentioned amide group-containing ethylenically unsaturated monomers to the total amount of the other ethylenically unsaturated monomers copolymerizable therewith (on a weight basis) is , 1 to 30% by weight: 99 to 70% by weight.
The composition ratio in the other ethylenically unsaturated monomer copolymerizable with the amide group-containing ethylenically unsaturated monomer is such that the Tg of the emulsion is set within the range of 50 to 90 ° C. Is optional.

The reason is that the Tg of the emulsion is 5
If the temperature is set lower than 0 ° C., the tensile strength of the nonwoven fabric subjected to the binder treatment at the time of heating is lowered, which is not preferable. Further, when the Tg of the emulsion exceeds 90 ° C., the polymerization stability is insufficient, a gelled product is formed, and a stable aqueous emulsion cannot be produced. Therefore, the Tg of the emulsion is 50 to 90.
It is necessary to set the temperature to ℃, and within that range, 65 to 8
It is preferably set to 0 ° C.

The glass transition temperature (Tg) of the emulsion referred to herein is the value obtained from the formula 1 by the usual weight fraction method.

[0014]

[Formula 1] 1 / Tg = (W _A / Tg _A ) + (W _B / Tg _B ) W _A : Weight fraction of A component W _B : Weight fraction of B component Tg _A : Glass transition point of A component Temperature (K) Tg _B : Glass transition temperature (K) of B component

The emulsifier and polymerization initiator used in the present invention are not particularly limited. For example, as the emulsifier, an anionic or nonionic emulsifier can be used or used in combination. As the polymerization initiator, persulfates such as potassium persulfate and ammonium persulfate, peroxides such as hydrogen peroxide, benzoyl peroxide, t-butyl hydroperoxide and cumene hydroperoxide are generally used. Water-soluble initiators are preferred. Further, it is no problem to use a chain transfer agent, n-dodecyl mercaptan, t-dodecyl mercaptan or the like, which is usually used in emulsion polymerization in the present invention, if necessary.

Thermosetting amino resin (B) used in the present invention
The amino resin (hereinafter simply referred to as “amino resin”) is not particularly limited, and a commercially available amino resin can be used. The amino resin includes urea resin and melamine resin. For example, Urea resin manufactured by Mitsui Toatsu Chemical Co., Ltd. has U-320,
TMF for melamine resin, U-3 for urea melamine resin
50 and others. In the case of urea resin, which is a kind of amino resin, a general production method is that the molar ratio of formaldehyde (F) and urea (U) is 1.0 as F / U.
Condensate at a ratio of ~ 3.0. Further, in the case of a melamine resin, condensation is performed at a molar ratio of formaldehyde (F) and melamine (M) of F / M of 1.5 to 6.0.
Further, these urea resins and melamine resins may be used alone or in any mixture.

The acrylamide polymer aqueous solution (C) used in the present invention has a polymer concentration of 22 to 60% and a Brookfield viscosity at 25 ° C. of 50.
0 ps (poises) or less, a weight average molecular weight of 500,000 to 10,000,000, and one or more selected from vinyl compounds represented by the following general formula (1) and / or salts thereof. This is an acrylamide polymer aqueous solution containing the vinyl compound (1) as a copolymerization component. General formula (1) (In the formula, R is a hydrogen atom or a lower alkyl group, and n is 1 to 8
Integer)

The acrylamide polymer in the present invention is a polymer formed from acrylamide and / or methacrylamide, or contains acrylamide and / or methacrylamide as a maximum component with respect to all monomer components constituting the acrylamide polymer. A copolymer, particularly acrylamide and /
Alternatively, it is preferable that the content of methacrylamide is 50 mol% or more.

The weight average molecular weight in the present invention can be determined by the static light scattering method. Specifically, the value can be obtained by using a multi-angle light scattering detector and creating a Jim plot. Alternatively, it can be obtained by creating a Debye plot by the GPC-MALLS method in which a multi-angle light scattering detector is connected to the GPC.

Generally, for measuring the molecular weight by the light scattering method,
The following basic formula of light scattering Kc / R (θ) = 1 / MwP (θ) + 2A ₂ c + ... R (θ) = scattered light at angle (θ) (Rayleigh coefficient)
Reduction intensity c = sample concentration Mw = weight average molecular weight A ₂ = second virial coefficient K = optical parameter P (θ) = angle scattering function. The weight average molecular weight in the present invention is G
GPC-LALL with low angle light scattering detector connected to PC
Similar to the S method, it means a value that ignores the second and subsequent terms that are the second virial coefficient. The value of the weight average molecular weight of the polymer measured by the light scattering method is N / 10 including N / 10 sodium nitrate.
/ 15 phosphate buffer (pH 7) can be measured as a solvent (eluent).

The acrylamide polymer aqueous solution in the present invention has a polymer concentration in the range of 22 to 60% by weight and a Brookfield viscosity at 25 ° C. of 500.
ps (poise) or less and a weight average molecular weight of 500,000 to
Although it is 10 million, from the viewpoint of the uniformity of the branched and crosslinked structure, for example, the concentration and the molecular weight thereof in the range that does not hinder the use of the binder for the non-woven fabric is about 500,000 at 25% concentration.
It is preferable that the concentration is 8,000,000, 500,000 to 6,000,000 at 30% concentration, 500,000 to 4,000,000 at 40% concentration, and 500,000 to 3,000,000 at 50% concentration.

The polymer concentration can be obtained by measuring the absolutely dry polymer concentration of the aqueous polymer solution. Examples of the measuring method include a hot air drying method and a ket method.

Examples of the acrylamide polymer of the present invention are typically obtained by copolymerizing acrylamide or methacrylamide with one or more compounds represented by the general formula (1) or salts thereof. Examples thereof include acrylamide polymers. In the sulfonic acid compound represented by the general formula (1), R is a hydrogen atom or a lower alkyl group, an alkyl group having 1 to 8 carbon atoms, and further preferably 1 to 3. Specifically, a methyl group,
An ethyl group, an n-propyl group, and an i-propyl group. The salt is, for example, an alkali metal salt such as sodium or potassium, an ammonium salt or the like.

Specific examples of the sulfonic acid compound represented by the general formula (1) include allyl sulfonic acid, sodium allyl sulfonate, methallyl sulfonic acid, sodium methallyl sulfonate and ammonium methallyl sulfonate. It can be illustrated. The addition amount of these compounds is 0.005 to 30 mol% based on the total amount of all the monomers constituting the acrylamide polymer, but is preferably 0 from the viewpoint of the uniformity of the branched and crosslinked structure of the polymer. .0
It is 1 to 20 mol%, and more preferably 0.05 to 10 mol%. These compounds can be used alone or in combination of two or more.

Furthermore, by using a crosslinkable vinyl monomer in addition to the compound represented by the general formula (1), the acrylamide polymer aqueous solution of the present invention can be easily obtained. When the crosslinkable vinyl monomer is specifically listed, methylenebis (meth) acrylamide, ethylenebis (meth) acrylamide, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, divinyl. Examples thereof include bifunctional crosslinkable monomers such as benzene, and polyfunctional crosslinkable monomers such as 1,3,5-triacryloylhexahydro-S-triazine, triallyl isocyanurate, and pentaerythritol triacrylate. . The amount of these crosslinkable monomers is 0.01 to 5 mol% based on the total amount of all the monomers constituting the acrylamide polymer, but from the viewpoint of the uniformity of the branched crosslinked structure of the polymer, it is 0. It is preferably from 01 to 2 mol%. These compounds may be used alone or in combination of two or more.

The acrylamide polymer aqueous solution in the present invention can be copolymerized with various vinyl monomers in addition to acrylamide and / or methacrylamide. They include ionic monomers, hydrophilic monomers, hydrophobic monomers and the like, and one or more kinds of these monomers can be applied.

Among the ionic monomers, examples of the anionic monomer include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid and salts thereof, vinyl sulfonic acid, styrene sulfonic acid, acrylamidomethyl. Propane sulfonic acid and salts thereof include, as the cationic monomer, N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylate, N, N-diethylaminopropyl (meth) acrylate, N, N-
Dimethylaminoethyl (meth) acrylamide, N, N
-Diethylaminoethyl (meth) acrylamide, N,
N-dimethylaminopropyl (meth) acrylamide,
Examples thereof include amines such as N, N-diethylaminopropyl (meth) acrylamide and salts thereof (including quaternary compounds).

Examples of the hydrophilic monomer include acetone acrylamide, N, N-dimethyl (meth) acrylamide, N-ethyl (meth) acrylamide, N, N-
Diethyl (meth) acrylamide, N-propylacrylamide, N-acryloylpyrrolidine, N-acryloylpiperidine, N-acryloylmorpholine, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, various methoxypolyethylene glycol (meth) acrylates, Examples thereof include N-vinyl-2-pyrrolidone.

Examples of the hydrophobic monomer include N, N-
Di-n-propyl (meth) acrylamide, Nn-butyl (meth) acrylamide, Nn-hexyl (meth) acrylamide, Nn-octyl (meth) acrylamide, N-tert-octyl (meth) acrylamide, N-alkyl (meth) acrylamide derivatives such as N-dodecylacrylamide, Nn-dodecylmethacrylamide, N, N-diglycidyl (meth) acrylamide, N- (4-glycidoxybutyl) (meth) acrylamide, N- N- (ω-glycidoxyalkyl) (meth) acrylamide derivatives such as (5-glycidoxypentyl) acrylamide, N- (6-glycidoxyhexyl) acrylamide, methyl (meth) acrylate, ethyl (meth) acrylate , Butyl (meth) acrylate, lauryl (meth (Meth) acrylate derivatives such as acrylate, 2-ethylhexyl (meth) acrylate and glycidyl (meth) acrylate, acrylonitrile, methacrylonitrile, vinyl acetate, vinyl chloride, vinylidene chloride, olefins such as ethylene, propylene and butene, styrene, Examples thereof include α-methylstyrene, butadiene, isoprene and the like.

The amount of the vinyl monomer used for the copolymerization varies depending on the type of the vinyl monomer and the combination thereof and cannot be generally stated, but it is preferably 0 to 50 mol%, more preferably 0 to 20. Suitable is mol%, more preferably 0.5 to 10 mol%.

Radical polymerization is preferred as the method for polymerizing the aqueous solution of the acrylamide polymer in the present invention.
Although water is used as the polymerization solvent, it is possible to use an organic solvent such as alcohol in combination within a range that does not impair the dispersibility due to precipitation and precipitation of the polymer in an aqueous solution having the above concentration.

The method for polymerizing the aqueous solution of the acrylamide polymer in the present invention may be batch polymerization in which all the monomers are charged in a reaction vessel at a time and polymerized, but a part or all of the monomers is dropped into the reaction vessel. The semi-batch (semi-batch) polymerization method of polymerizing is more preferable. By performing the semi-batch (semi-batch) polymerization method,
Not only the heat of polymerization in the high-concentration monomer solution can be easily removed, but also the branched and cross-linked structure of the polymer can be easily homogenized to control the molecular structure.

The polymerization concentration (monomer + polymer concentration during polymerization) is not particularly limited, but in the case of batch (batch) polymerization,
It is approximately 22 to 40% by weight. Polymerization may be carried out at a concentration lower than 22% by weight and a concentration of 22% by weight or more may be used as the polymer aqueous solution by the concentration operation, but it is disadvantageous from the economical point of view. In the case of semi-batch (semi-batch) polymerization, the polymerization concentration in the reactor during the dropping can be arbitrarily selected by adjusting the initial monomer concentration in the reactor and the dropping rate of the monomer. However, the polymerization concentration at the end of dropping is approximately 22 to 60% by weight. in this case,
Similar to batch (batch) polymerization, it is possible to carry out polymerization at a concentration lower than 22% by weight, and to carry out a concentration operation to obtain an aqueous polymer solution having a concentration of 22% by weight or more, but there are disadvantages as described above.

The polymerization initiator is not particularly limited, but a water-soluble one is preferable. It may be added to the aqueous monomer solution all at once or may be added dropwise. As specific polymerization initiators, examples of persulfate-based and peroxide-based initiators include ammonium persulfate, potassium persulfate, sodium persulfate, hydrogen peroxide, benzoyl peroxide, and tert-butyl peroxide. In this case, it is preferably used alone, but it can also be used as a redox polymerization initiator in combination with a reducing agent. Examples of the reducing agent include sulfite, bisulfite, low-order ionized salts such as iron, copper and cobalt, organic amines such as N, N, N ′, N′-tetramethylethylenediamine, aldose and ketose. And reducing sugars.

Azo compounds are also the most preferred initiators in the present invention, and are 2,2'-azobis-2-methylpropionamidine hydrochloride, 2,2'-azobis-2,
4-dimethylvaleronitrile, 2,2'-azobis-
N, N'-dimethyleneisobutylamidine hydrochloride, 2,
2'-azobis-2-methyl-N- (2-hydroxyethyl) -propionamide, 2,2'-azobis-2-
(2-Imidazolin-2-yl) -propane and its salt, 4,4'-azobis-4-cyanovaleric acid and its salt, etc. can be used. Furthermore, it is also possible to use two or more of the above-mentioned polymerization initiators in combination. The amount of the polymerization initiator is generally 0.001 to 5% by weight based on the monomer.

The polymerization temperature is about 30 to 90 ° C. in the case of a single polymerization initiator, and the starting temperature in the case of a redox type polymerization initiator is lower, about 5 to 50 ° C. Further, it is not necessary to maintain the same temperature during the polymerization and may be appropriately changed as the polymerization proceeds, but since the temperature is generally raised by the heat of polymerization generated with the progress of the polymerization, it is necessary to add cooling if necessary. In some cases. The atmosphere in the polymerization container at that time is not particularly limited, but it is preferable to substitute an inert gas such as nitrogen gas for rapid polymerization. The polymerization time is not particularly limited, but is generally 1 to 20 hours including the dropping time in the semi-batch (semi-batch) polymerization. The polymerization pH is not particularly limited, but the pH may be adjusted to carry out the polymerization if necessary. In this case, usable pH adjusters include alkalizing agents such as sodium hydroxide, potassium hydroxide and ammonia, mineral acids such as phosphoric acid, sulfuric acid and hydrochloric acid, and organic acids such as formic acid and acetic acid.

The non-woven fabric binder of the present invention can be obtained by mixing the thus obtained aqueous emulsion (A), amino resin (B) and aqueous acrylamide polymer solution (C). The mixing ratio is 1 total solids.
As 00 parts by weight, (A) :( B) :( C) = 3 to 9
6:96 to 3: 1 to 10 parts by weight, more preferably 10 to 78:78 to 10: 2 to 8 parts by weight, and most preferably 20 to 40:77 to 53: 3 to 7 parts by weight. Use to be.

When the amount of the aqueous emulsion (A) is less than 3 parts by weight based on the total amount of the binder, the treated non-woven fabric has a low elongation in the normal state, and when it exceeds 96 parts by weight, the treated non-woven fabric is in the normal state and under heat. The tension is low, which is not preferable.

Further, the non-woven fabric treated with the thermosetting amino resin (B) in an amount of less than 3 parts by weight based on all binders is
When the tensile strength in the normal state is low, and when it exceeds 96 parts by weight, the treated nonwoven fabric has low elongation in the normal state and heat, which is not preferable.

Further, when the amount of the acrylamide polymer aqueous solution (C) is less than 1 part by weight with respect to the total amount of the binder, the treated nonwoven fabric has insufficient anti-tensile strength when heated, and when it exceeds 10 parts by weight, the binder liquid becomes Not only does the viscosity increase, the workability deteriorates, but the treated non-woven fabric has a higher tensile strength in the normal state and a higher tensile strength at the time of heating, but the elongation in the normal state becomes lower, which causes a new decrease in tear strength and water resistance. It is not preferred.

The non-woven fabric binder thus obtained is
Not only for a non-woven fabric for asphalt impregnation, but various additives such as a curing agent for an amino resin, a formalin catcher agent, and the like are added depending on the application, and it can be used as various non-woven fabric binders.

[0042]

[Reference Example 1]

Production of Aqueous Emulsion Used in Examples and Comparative Examples Pure water 159 g, sodium dodecylbenzenesulfonate (hereinafter abbreviated as DBS) 1 g, in a mixing tank equipped with a stirrer,
Styrene 40 g, methyl methacrylate 244 g, butyl acrylate 80 g, 2 hydroxyethyl methacrylate 8 g, methacrylic acid 8 g, methacrylamide 20 g
Was charged and stirred at room temperature for 30 minutes to obtain an emulsion a. Then, in a 1-liter glass reactor equipped with a stirrer, a reflux condenser, a dropping device and a thermometer, 437 g of pure water,
DBS 1g was charged, and the temperature was 75 in a nitrogen atmosphere with stirring.
2 g of potassium persulfate was added at 0 ° C. to obtain solution b. Next, the previously prepared emulsion a is added to this solution b over 3 hours,
The reaction was allowed to proceed, and the reaction was terminated over a further 3 hours. After the reaction solution was cooled to room temperature, aqueous ammonia was added as a neutralizing agent to adjust the pH to 8 to obtain an aqueous emulsion A1 having a target Tg of 60 ° C. Further, an aqueous emulsion of A2 to A5 was obtained by the same method except that the monomer composition was changed. The monomer composition and Tg of the product are shown in Table 1 together.

Reference Example 2 Thermosetting Amino Resin Used in Examples and Comparative Examples Selected from commercially available thermosetting amino resins of Mitsui Toatsu Chemicals, Inc., shown in Table 2.

Reference Example 3 Production of Aqueous Solution of Acrylamide Polymer Used in Examples and Reference Examples The weight average molecular weight was measured by using Sh manufactured by Showa Denko KK
odex ^(R) GPCSYSTEM-11 Sho-d
An exOHpak SB80M was connected, and a differential refractometer and a multi-angle light scattering detector manufactured by WYATT TECHNOLOGY Co. were used together as detectors.

[Reference Example 3-1] Pure water (306 g) was charged into a five-necked flask (hereinafter referred to as a reaction vessel) equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen gas inlet tube, and a dropping port. The internal temperature was adjusted to 80 ° C. while blowing. On the other hand, a solution in which 283 g of 50% acrylamide aqueous solution, 0.31 g of methylenebisacrylamide and 1.58 g of sodium methallylsulfonate were mixed and dissolved, and a pure content of 84%
60 g of an aqueous solution in which 0.24 g of 4,4′-azobis-4-cyanovaleric acid was dissolved was prepared, and each solution was uniformly added dropwise into the reaction container over 150 minutes. During this period, the temperature inside the reaction vessel was kept constant at 80 ° C. After the completion of the dropping, the polymerization was continued at 80 ° C. for 3 hours, and the reaction was terminated by cooling to give a Brookfield viscosity of 120 ps at 25 ° C.
An acrylamide polymer aqueous solution was obtained. This polymer is designated as C1. 1 g of C1 was precisely weighed in an aluminum cup of known weight, diluted with about 1 g of pure water, and dried in a hot air drier at 105 ° C. for 3 hours to obtain an absolutely dry polymer concentration of 23.8%. It was The weight average molecular weight of C1 was 1.76 million as measured by the above method.

[Reference Example 3-2] A five-necked flask (hereinafter referred to as a reaction vessel) equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen gas inlet tube, and a dropping port was charged with 288 g of pure water, and nitrogen gas was added. The internal temperature was adjusted to 80 ° C. while blowing. On the other hand, 283 g of 50% acrylamide aqueous solution, 0.31 g of methylenebisacrylamide, 1.58 g of sodium methallylsulfonate, and 0.24 g of 84% pure 4,4′-azobis-4-cyanovaleric acid were mixed and dissolved, A monomer and initiator mixed solution was prepared. Then this monomer,
The initiator mixture was evenly dropped into the reaction vessel over 150 minutes. During this period, the temperature inside the reaction vessel was kept constant at 80 ° C. The temperature of the mixed solution of the monomer and the initiator is 15 to 2
The temperature was kept at 5 ° C., and care was taken not to cause polymerization before dropping and to prevent the monomer from precipitating. Presence or absence of polymerization of the mixed solution of the monomer and the initiator before dropping was confirmed by allowing the mixed solution under the same conditions to stand for 2 hours and adding it to methanol. After the dropping was completed, the polymerization was continued at 80 ° C. for 3 hours, and the reaction was terminated by cooling to obtain an aqueous acrylamide polymer solution having a Brookfield viscosity of 33.4 ps at 25 ° C. This polymer is designated as C2. Various physical properties of C2 were measured in the same manner as in Reference Example 3-1.

Reference Example 3-3 A 5-necked flask (hereinafter referred to as a reaction vessel) equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen gas inlet tube, and a dropping port was charged with 293 g of pure water. The internal temperature was adjusted to 80 ° C. while blowing. On the other hand, 2823 g of 50% acrylamide aqueous solution, 0.31 g of methylenebisacrylamide, 3.18 g of sodium methallylsulfonate, and 0.25 g of 2,2′-azobis-2-methyl-N- (2-hydroxyethyl) -propionamide. An aqueous solution prepared by mixing and dissolving was prepared and uniformly dropped into the reaction vessel over 150 minutes. During this period, the temperature inside the reaction vessel was kept constant at 80 ° C., and the temperature of the monomer / initiator mixed solution was kept at 15 to 25 ° C. during the dropping. After the completion of the dropping, the polymerization was continued at 80 ° C. for 3 hours, and the reaction was terminated by cooling to obtain an aqueous acrylamide polymer solution having a Brookfield viscosity at 25 ° C. of 37.7 ps. This polymer is designated as C3. Various physical properties of C3 were measured in the same manner as in Reference Example 3-1.

[Reference Example 3-4] A five-necked flask (hereinafter referred to as a reaction vessel) equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen gas inlet tube, and a dropping port was charged with 296 g of pure water, and nitrogen gas was added. The internal temperature was adjusted to 80 ° C. while blowing. On the other hand, an aqueous solution obtained by mixing and dissolving 421 g of 50% acrylamide aqueous solution, 0.46 g of methylenebisacrylamide, 6.22 g of sodium methallylsulfonate, and 0.36 g of 84% pure 4,4′-azobis-4-cyanovaleric acid. Was adjusted and uniformly dropped into the reaction vessel over 150 minutes. During this period, the temperature inside the reaction vessel was kept constant at 80 ° C, and during the dropping, the temperature of the mixed solution of the monomer and the initiator was 15 to 25 ° C.
Kept. After the dropping was completed, the polymerization was continued at 80 ° C. for 3 hours, and the reaction was terminated by cooling to obtain an aqueous acrylamide polymer solution having a Brookfield viscosity of 200 ps at 25 ° C. This polymer is designated as C4. Various physical properties of C4 were measured in the same manner as in Reference Example 3-1.

[Reference Example 3-5] A five-necked flask (hereinafter referred to as a reaction vessel) equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen gas inlet tube, and a dropping port was charged with 325 g of pure water. The internal temperature was adjusted to 80 ° C. while blowing. On the other hand, 550 g of 50% acrylamide aqueous solution, 14.4 g of methylenebisacrylamide, 111 g of sodium methallylsulfonate, and 0.93 g of 4,4′-azobis-4-cyanovaleric acid having a purity of 84% were mixed and dissolved to obtain a monomer, The initiator mixture was prepared. Then this monomer,
The initiator mixed solution was evenly dropped into the reaction vessel over 150 minutes. During this period, the temperature in the reaction vessel was kept constant at 80 ° C,
The temperature of the mixed solution of the monomer and the initiator was kept at 15 to 25 ° C. After the dropping was completed, the polymerization was continued at 80 ° C. for 3 hours, and the reaction was terminated by cooling to obtain an aqueous acrylamide polymer solution having a Brookfield viscosity of 10.7 ps at 25 ° C. This polymer is designated as C5. Various physical properties of C5 were measured in the same manner as in Reference Example 3-1.

[Reference Example 3-6] 203 g of pure water was charged into a five-necked flask (hereinafter referred to as a reaction vessel) equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen gas inlet tube, and a dropping port, and nitrogen gas was charged. The internal temperature was adjusted to 80 ° C. while blowing. On the other hand, 747 g of 60% acrylamide aqueous solution, 1.02 g of methylenebisacrylamide, 52.8 g of sodium methallylsulfonate, and 0.66 g of 4,4′-azobis-4-cyanovaleric acid having a purity of 84% were mixed and dissolved, A monomer and initiator mixed solution was prepared. Then this monomer,
The initiator mixed solution was evenly dropped into the reaction vessel over 150 minutes. During this period, the temperature in the reaction vessel was kept constant at 80 ° C,
The temperature of the mixed solution of the monomer and the initiator was kept at 15 to 25 ° C. After the dropping was completed, the polymerization was continued at 80 ° C. for 3 hours, and the reaction was terminated by cooling to obtain an aqueous acrylamide polymer solution having a Brookfield viscosity of 47.6 ps at 25 ° C. This polymer is designated as C6. Various physical properties of C6 were measured in the same manner as in Reference Example 3-1.

[Reference Example 3-7] A five-necked flask (hereinafter referred to as a reaction vessel) equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen gas inlet tube, and a dropping port was charged with 363 g of pure water. The internal temperature was adjusted to 80 ° C. while blowing. On the other hand, 284 g of 50% acrylamide aqueous solution, 0.31 g of methylenebisacrylamide, and 84% pure 4
An aqueous solution in which 0.24 g of 4′-azobis-4-cyanovaleric acid was mixed and dissolved was uniformly dropped into the reaction vessel over 150 minutes. During this period, the temperature in the reaction vessel was kept constant at 80 ° C., and the mixed solution was kept at 15 to 25 ° C. or lower during dropping.
However, the reaction solution became highly viscous during the dropping, lost its fluidity, and finally gelled. This gelled product is designated as C7. Even if C7 was further diluted with water, it did not disperse and dissolve, and various physical properties could not be obtained.

[Reference Example 3-8] A five-necked flask (hereinafter referred to as a reaction vessel) equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen gas inlet tube, and a dropping port was charged with 228 g of pure water, and nitrogen gas was added. The internal temperature was adjusted to 80 ° C. while blowing. On the other hand, a solution prepared by mixing 283 g of a 50% acrylamide aqueous solution, 0.31 g of methylenebisacrylamide and 30 g of isopropyl alcohol, and 60 g of an aqueous solution in which 0.24 g of 84% pure 4,4′-azobis-4-cyanovaleric acid was dissolved. Was uniformly added dropwise into the reaction container over 150 minutes. During this period, the temperature inside the reaction vessel was kept constant at 80 ° C. After the dropping was completed, the polymerization was continued at 80 ° C. for 3 hours, and the reaction was terminated by cooling to obtain an aqueous acrylamide polymer solution having a Brookfield viscosity of 13.3 ps at 25 ° C. This polymer is designated as C8. C8
Was measured in the same manner as in Reference Example 3-1.

[Reference Example 3-9] Pure water 639 g and 50% acrylamide aqueous solution 360 g were placed in a five-necked flask equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen gas inlet tube, and a dropping port.
Was charged, and the internal temperature was adjusted to 30 ° C. while blowing nitrogen gas. Next, 0.67 g of ammonium persulfate and 0.33 g of sodium bisulfite were added and reacted to obtain an aqueous acrylamide polymer solution. After cooling, the Brookfield viscosity at 25 ° C. was measured and found to be 50 ps.
This polymer is designated as C9. Reference example 3 based on various physical properties of C9
It measured like -1.

[Reference Example 3-10] Stirrer, reflux condenser,
In a five-necked flask equipped with a thermometer, a nitrogen gas introduction tube, and a dropping port, 800 g of pure water and 200% acrylamide aqueous solution 200
g was charged and the internal temperature was adjusted to 30 ° C. while blowing nitrogen gas. Next, 0.30 g of ammonium persulfate and 0.15 g of sodium bisulfite were added and reacted to obtain an acrylamide polymer aqueous solution. After cooling, the Brookfield viscosity at 25 ° C. was measured and found to be 125 ps. This polymer is designated as C10. Various physical properties of C10 were measured in the same manner as in Reference Example 3-1. Reference Example 3-
Various physical properties of the polymers obtained in 1 to 10 are summarized in Table 3.

[0055]

[Table 1]

[0056]

[Table 2] U-350: urea-melamine resin TMF: melamine resin U-320: urea resin

[0057]

[Table 3] 1) AM: Acrylamide 2) MBA: Methylenebisacrylamide 3) SMS: Sodium methallylsulfonate 4) Initiator A: 4,4′-azobis-4-cyanovaleric acid B: 2,2′-Azobis-2- Methyl-N- (2-hydroxyethyl) -propionamide C: Ammonium persulfate and sodium bisulfite are used in a ratio of 2: 1 5) Initiator amount: Grams per monomer mole 6) DPC: Absolute dry Polymer concentration 7) Mw: Weight average molecular weight

Example 1 93 g of the aqueous emulsion A1 and the aqueous emulsion A1 shown in Table 1 so that the solid content ratio of the thermosetting amino resin and the aqueous solution of the acrylamide polymer was 15: 80: 5.
And the thermosetting amino resin B1 shown in Table 2; 363 g
And an acrylamide polymer aqueous solution shown in Table 3; 2
1 g is weighed in a container equipped with a stirrer, and further 3 g of a thermosetting curing agent for amino resin (Catalyst P ... manufactured by Mitsui Toatsu Kagaku Co., Ltd.) and pure water so that the whole solution has a concentration of 25%; 490 g
Was added and stirred and mixed for 3 minutes, and then the mixed solution was 30 cm in length.
Transfer to a pallet measuring 30 cm wide × 3 cm deep and have a basis weight of 1
200g of mangle after dipping 30g30cm of spunbond web made of polyester fiber of 00g / m ²
/ M ² and squeeze it for 5 minutes in a dryer set at 110 ° C, and then place it in a dryer set at 180 ° C for 3 minutes.
It was left for a minute to obtain the target nonwoven fabric. The basis weight of the nonwoven fabric after drying was 125 g / m ² .

Next, the nonwoven fabric was evaluated by the following method, and the results are shown in Table 4. [Evaluation of non-woven fabric] 1) Preparation of test piece The processed non-woven fabric was cut to prepare a test piece measuring 15 cm in length and 5 cm in width. 2) Tensile test Using a self-recording tensile tester (manufactured by Shimadzu Corporation), a tensile test was performed in an atmosphere of 20 ° C and 160 ° C.
The test condition is that the distance between chucks is 10 cm and the pulling speed is 2
The evaluation was made at 00 mm / min.

Examples 2 to 6 Nonwoven fabrics were prepared and evaluated in exactly the same manner as in Example 1 except that the composition ratio of the binder was adjusted to the composition shown in Table 4 (shown in parts). The results are shown in Table 4.

Comparative Examples 1 to 6 Nonwoven fabric binders were prepared and evaluated in exactly the same manner as in Example 1 except that the binder ratio was adjusted to the composition shown in Table 4 (shown in parts). . The results are shown in Table 4.

[0062]

[Table 4]

[0063]

As is apparent from Table 4, the non-woven fabric binder of the present invention has a higher tensile strength and a higher tensile strength than the conventional product while maintaining appropriate flexibility in the normal state. It can be seen that it is a binder with very little deterioration. INDUSTRIAL APPLICABILITY The present invention enables the production of a nonwoven fabric excellent in both tensile strength under heat and flexibility, has an industrial significance, and is particularly useful as a binder for an asphalt-impregnated nonwoven fabric used for waterproofing a building. .

Claims (3)

[Claims] 1. A non-woven fabric binder comprising an aqueous emulsion (A), a thermosetting amino resin (B), and an aqueous acrylamide polymer solution (C), wherein the aqueous acrylamide polymer solution (C) has a polymer concentration of 22-.
The vinyl compound represented by the following general formula (1) has a Brookfield viscosity of 500 ps or less, a weight average molecular weight of 500,000 to 10,000,000, and a ratio of 60% by weight.
Alternatively, a nonwoven fabric binder containing, as a copolymerization component, one or more vinyl compounds selected from salts thereof. General formula (1) (In the formula, R is a hydrogen atom or a lower alkyl group, and n is 1 to 8
Integer) 2. The total solid content of the aqueous emulsion (A), the thermosetting amino resin (B) and the aqueous solution of the acrylamide polymer (C) is 100 parts by weight, and each is 3 parts.
The binder for non-woven fabric according to claim 1, wherein the binder is a mixture of 96:96 to 3: 1 to 10 parts by weight. 3. The aqueous emulsion (A) contains 1 to 30% by weight of an amide group-containing ethylenically unsaturated monomer, and another ethylenically unsaturated monomer 9 copolymerizable therewith.
The non-woven fabric binder according to claim 1, which is obtained by emulsion polymerization of 9 to 70% by weight and has a glass transition temperature (Tg) of 50 to 90 ° C.