KR20230080764A - Nonionic reactive surfactant, aqueous adhesive composition comprising the same, and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a surfactant composition for a pressure-sensitive adhesive, a pressure-sensitive adhesive composition containing the same, and a method for preparing the same. Since the surfactant prepared in the present invention was included in the pressure-sensitive adhesive and showed excellent adhesion performance and emulsion stability, it is widely used in the production of pressure-sensitive adhesive. can be applied

Description

Nonionic reactive surfactant, aqueous adhesive composition containing the same, and method for preparing the same

The present invention relates to a surfactant composition for a pressure-sensitive adhesive, a method for preparing the same, and a pressure-sensitive adhesive including the same, and relates to a water-based pressure-sensitive adhesive composition including a nonionic reactive surfactant and an anionic reactive surfactant having excellent heat resistance and peel strength.

Conventionally, most commonly used pressure-sensitive adhesives are solvent-type pressure-sensitive adhesives prepared by using a volatile organic solvent as a solvent. However, as the industry advances, environmental regulations are gradually being strengthened, whereas many environmental problems are caused when volatile organic solvents are used. Therefore, in the field of adhesives, there is an increasing demand for adhesives containing less environmentally harmful components.

In accordance with these demands, water-based or non-solvent-type pressure-sensitive adhesives using water as a solvent that can replace solvent-type pressure-sensitive adhesives have recently been developed.

Water-based adhesives are used for labels, electrical/electronic tapes, construction/interior tapes, automotive tapes, other tapes, and medical applications. proportion is increasing.

Aqueous adhesives are prepared by emulsion polymerization using monomer mixtures, initiators, surfactants, emulsifiers, and additives (tackifier, antifoaming agent, wetting agent, leveling agent, etc.) It is a method of polymerizing a monomer insoluble in water or a monomer with low solubility in water by using a dispersion function.

These water-based adhesives have a problem in that adhesive physical properties such as initial adhesive strength, peel strength, and holding power are significantly lower than solvent-based adhesives in terms of performance, and additives such as surfactants used during emulsion polymerization are pointed out as the main cause.

In this regard, Korean Patent Registration No. 10-2295720 relates to an adhesive composition containing an acrylic copolymer, water, and a surfactant, and suggests various sulfate-type anionic surfactants as the surfactant.

Efforts to improve initial adhesion, cohesion and water resistance by using special surfactants (reactive emulsifiers, polymeric emulsifiers, etc.) Although some multinational companies are trying, the need to develop suitable emulsifiers is increasing because they still have problems such as aggregation, unreacted emulsifiers and foaming depending on the type of reactive emulsifier.

Korean Registered Patent No. 10-2295720 (registered on 21.08.25)

The nonionic reactive surfactant of the present invention has been devised to solve the above problems, and provides a nonionic reactive surfactant formed by the reaction of polyoxyethylene alkylphenyl ether and an unsaturated carboxylic acid having 4 to 6 carbon atoms. for that purpose

In addition, another object of the present invention is to provide an aqueous pressure-sensitive adhesive composition comprising the nonionic reactive surfactant, anionic reactive surfactant, acrylate monomer, aqueous solvent, and initiator of the present invention.

In addition, the present invention comprises the steps of (a) reacting polyoxyethylene alkylphenyl ether by adding benzene and an unsaturated carboxylic acid having 4 to 6 carbon atoms; (b) adding a catalyst to the product of step a; (c) obtaining an oily layer after layer separation of the product of step b; Another object is to provide a method for producing a non-ionic reactive surfactant comprising; and (d) removing the solvent from the oily layer.

In addition, the present invention (A) mixing an aqueous solvent, an anionic reactive surfactant, a nonionic reactive surfactant formed by the reaction of polyoxyethylene alkylphenyl ether with an unsaturated carboxylic acid having 4 to 6 carbon atoms, and acrylic acid, ( B) mixing an acrylate monomer with the mixture of step (A) to form a pre-emulsion, (C) mixing an initiator and sodium metabisulfite with a portion of the pre-emulsion, (D) the step (C) ) Another object is to provide a method for producing a water-based pressure-sensitive adhesive comprising the step of dropping the remaining pre-emulsion into a mixture of, and (E) neutralizing.

The present invention may also have as its object to achieve other objects that can be easily derived by a person of ordinary skill in the art from these objects and the overall description of this specification in addition to the above clear objects.

In order to achieve the above object, the nonionic reactive surfactant of the present invention is characterized in that it is formed by the reaction of polyoxyethylene alkylphenyl ether with an unsaturated carboxylic acid having 4 to 6 carbon atoms.

And, the non-ionic reactive surfactant may be a surfactant for water-based pressure-sensitive adhesive.

And, in the alkylphenyl, alkyl may have 8 to 16, 10 to 14, or 12 to 14 carbon atoms.

Also, in the above alkylphenyl, alkyl may be linear or branched.

And, the polyoxyethylene alkylphenyl ether may have 7 to 40, 20 to 30, or 24 to 30 oxyethylene repeating units.

And, the nonionic reactive surfactant may have a vinyl group at the end.

And, the alpha carbon of the unsaturated carboxylic acid may have sp ³ hybridization.

And, the unsaturated carboxylic acid is 3-butenoic acid, 3-pentenoic acid, 4-pentenoic acid, 2-methyl-3-butenoic acid, 3-hexenoic acid, 4-hexenoic acid, 5-hexenoic acid, 4-methyl- 3-pentenoic acid, 4-methyl-4-pentenoic acid, 3-methyl-3-pentenoic acid, 3-methyl-4-pentenoic acid, 3-ethyl-3-butenoic acid, 2-methyl-3-pentenoic acid, 2-methyl-4-pentenoic acid, 2,2-diethyl-3-butenoic acid, 2,3-diethyl-3-butenoic acid, or 2-ethyl-3-butenoic acid.

In addition, the nonionic reactive surfactant may be represented by Formula 1 below.

[Formula 1]

In Formula 1, n is 7 to 40, 20 to 30, or 24 to 30.

On the other hand, the aqueous pressure-sensitive adhesive composition of the present invention is characterized by including the nonionic reactive surfactant, anionic reactive surfactant, acrylate monomer, aqueous solvent, and initiator of the present invention.

And, with respect to 100 parts by weight of the acrylate monomer,

0.01 to 5 parts by weight of the nonionic reactive surfactant, 0.05 to 1 part by weight, 0.1 to 0.5 parts by weight, and

0.01 to 5 parts by weight, 0.05 to 1 part by weight, or 0.1 to 0.5 parts by weight of the anionic reactive surfactant may be included.

And, the water-based pressure-sensitive adhesive composition,

Based on 100 parts by weight of the acrylate monomer,

0.01 to 5 parts by weight, 0.05 to 1 part by weight, 0.1 to 0.5 parts by weight of the initiator and

It may include 30 to 200 parts by weight of the aqueous solvent, 40 to 100 parts by weight, or 50 to 80 parts by weight.

In addition, the anionic reactive surfactant may be a polyoxyethylene-based anionic surfactant having a vinyl group at the terminal.

And, the anionic reactive surfactant may have a sulfonic acid or sulfonate functional group.

In addition, the anionic reactive surfactant may be represented by Formula 2 below.

[Formula 2]

In Formula 2, R is alkyl, m is 5 to 45, 10 to 40, or 24 to 30, and X is SO ₃ NH ₄ or SO ₃ Na.

In addition, the acrylate monomer may be selected from the group consisting of acrylic acid, n-butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, and mixtures thereof.

And, the acrylate monomer is acrylic acid 1 part by weight, 2-ethylhexyl acrylate 20 to 45 parts by weight, 22 to 40 parts by weight, or 24 to 38 parts by weight, n-butyl acrylate 25 to 70 parts by weight, 30 to 30 parts by weight 65 parts by weight, or 36 to 62 parts by weight, methyl methacrylate may include 8 to 38 parts by weight, 10 to 30 parts by weight, or 12 to 28 parts by weight.

In addition, the initiator may be ammonium persulfate, sodium metabisulfite, or a mixture thereof.

In addition, the aqueous pressure-sensitive adhesive composition may include one or more additives selected from the group consisting of a tackifier, an emulsifier, an antifoaming agent, a stabilizer, a pH adjuster, a leveling agent, a wetting agent, a biocide, and mixtures thereof. .

In addition, the water-based adhesive may be used for labels, electric/electronic tapes, construction/interior tapes, automotive tapes, or medical adhesives.

On the other hand, the method for producing a nonionic reactive surfactant of the present invention,

(a) reacting by adding benzene and an unsaturated carboxylic acid having 4 to 6 carbon atoms to polyoxyethylene alkylphenyl ether;

(b) adding a catalyst to the product of step a;

(c) obtaining an oily layer after layer separation of the product of step b; and

(d) removing the solvent from the oil phase; characterized in that it comprises a.

In addition, the nonionic reactive surfactant may be represented by the following Chemical Formula 1, and the polyoxyethylene alkylphenyl ether may be represented by the following Chemical Formula 3.

[Formula 1]

[Formula 3]

In Formula 1 and Formula 3, n is 7 to 40, 20 to 30, or 24 to 30.

Also, the catalyst may be para-toluenesulfonic acid.

And, the step (a) may be reacted for 120 to 240 minutes at 40 to 80 ℃.

And, the step (b) may be reacted for 18 to 36 hours at 60 to 100 ℃.

On the other hand, the manufacturing method of the water-based pressure-sensitive adhesive of the present invention,

(A) mixing an aqueous solvent, an anionic reactive surfactant, a nonionic reactive surfactant formed by the reaction of polyoxyethylene alkylphenyl ether with an unsaturated carboxylic acid having 4 to 6 carbon atoms, and acrylic acid;

(B) forming a pre-emulsion by mixing an acrylate monomer with the mixture of step (A);

(C) mixing an initiator and sodium metabisulfite with a portion of the pre-emulsion;

(D) dropping the remaining pre-emulsion into the mixture of step (C), and

(E) characterized in that it comprises the step of neutralizing.

In the step (B), dodecylmercaptan may be added.

In the step (D), an initiator may be additionally added after dropping.

And, the acrylate monomer may be selected from the group consisting of acrylic acid, n-butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, and mixtures thereof.

And, the initiator may be ammonium persulfate.

In addition, the neutralizing step may be neutralizing with weak acidity by introducing a mixture of an aqueous solvent and ammonia water.

And, after the neutralization, a step of filtering may be included.

The surfactant according to the present invention is a nonionic surfactant, and when used in an adhesive, it has an appropriate viscosity and average particle size, and thus can exhibit excellent coating properties and adhesive properties.

In addition, according to the present invention, it is possible to provide a water-based adhesive composition excellent in both peel strength and heat resistance holding power.

In addition, according to the present invention, layer separation does not occur during the preparation of the pre-emulsion, and air bubbles or agglomerates do not occur during the preparation of the pressure-sensitive adhesive emulsion, so that a pressure-sensitive adhesive composition of excellent quality can be manufactured.

1 shows H-NMR results of a surfactant prepared by a manufacturing method according to an embodiment of the present invention.
Figure 2 shows the ¹³ C-NMR results of the surfactant prepared by the manufacturing method according to an embodiment of the present invention.
3 shows H-NMR results of a surfactant prepared by a manufacturing method according to an embodiment of the present invention.
Figure 4 shows the ¹³ C-NMR results of the surfactant prepared by the manufacturing method according to an embodiment of the present invention.
5 shows H-NMR results of a surfactant prepared by a manufacturing method according to an embodiment of the present invention.
6 shows ¹³ C-NMR results of a surfactant prepared by a manufacturing method according to an embodiment of the present invention.
7 schematically shows a method for manufacturing a pressure-sensitive adhesive composition according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail.

However, the following is only a detailed description by exemplifying specific embodiments, and since the present invention may be variously changed and may have various forms, the present invention is not limited to the specific embodiments illustrated. It should be understood that the present invention includes all modifications, equivalents and substitutes included in the spirit and scope of the present invention.

In addition, in the following description, many specific details such as specific components are described, which are provided to help a more general understanding of the present invention, and it is common in the art that the present invention can be practiced without these specific details. It will be self-evident to those who have the knowledge of And, in describing the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted.

And, the terms used in this application are only used to describe specific embodiments, and are not intended to limit the present invention. Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and unless explicitly defined in the present application, they should not be interpreted in an ideal or excessively formal meaning. don't

In this application, expressions in the singular number include plural expressions unless the context clearly dictates otherwise.

In this application, terms such as 'comprise', 'include' or 'having' are intended to indicate that the features, components (or components), etc. described in the specification exist, but one or more other features or It does not mean that components or the like do not exist or cannot be added.

The present invention has the advantage of being environmentally friendly, but in order to overcome the limitations of conventional water-based pressure-sensitive adhesives having low water resistance and poor adhesive properties, as a result of intensive research to prepare a surfactant for use in water-based pressure-sensitive adhesives, the present invention was completed.

The nonionic reactive surfactant of the present invention is characterized by being formed by the reaction of polyoxyethylene alkylphenyl ether with an unsaturated carboxylic acid having 4 to 6 carbon atoms. The hydrophile-lipophile balance (HLB) of the nonionic reactive surfactant of the present invention shows a value of 11 to 16, considering that it has excellent efficacy as an emulsifier for aqueous adhesives when it has an HLB value within the above range, the surfactant of the present invention It can be expected that the composition will exhibit excellent physical properties when included in the pressure-sensitive adhesive. Therefore, it can be used as a surfactant for various pressure-sensitive adhesives in addition to the surfactant for water-based pressure-sensitive adhesives, and has the advantage of being able to change HLB relatively freely, and it has been confirmed that its applicability is relatively higher than that of ionic surfactants.

As an example, a nonionic reactive surfactant may be formed by a reaction as shown in Scheme 1 below.

[Scheme 1]

The alkyl of the polyoxyethylene alkylphenyl ether is a carbon chain having 8 to 16, 10 to 14, or 12 to 14 carbon atoms as a carbon backbone and no unsaturated bonds. The alkyl of the polyoxyethylene alkylphenyl ether may be straight chain or branched chain. When the alkyl group is less than or greater than the above range, a problem in that adhesiveness decreases occurs. In particular, it was confirmed that when the length of the alkyl group is shortened, the heat resistance retention ability is remarkably lowered.

In addition, the polyoxyethylene alkylphenyl ether may have 7 to 40, 20 to 30, or 24 to 30 oxyethylene (CH ₂ CH ₂ O; EO) repeating units. When the oxyethylene repeating unit is less than the above range, heat resistance retention may be reduced, and when it exceeds the above range, poor adhesive base emulsion is caused due to poor emulsification.

The nonionic reactive surfactant of the present invention may have a vinyl group at the end. As shown in Reaction Scheme 1, the vinyl group may be derived from an unsaturated carboxylic acid, which is a reactant forming a non-ionic reactive surfactant.

The unsaturated carboxylic acid may be a carboxylic acid compound having 4 to 6 carbon atoms and one or more unsaturated bonds, preferably one. The unsaturated bond may be present at the terminal. Also, the unsaturated carboxylic acid may be other than acrylic acid or a derivative thereof. The unsaturated carboxylic acid may be characterized in that the alpha carbon has sp ³ hybridization, which may mean that the C=C double bond and the C=O double bond are not conjugated.

For example, the unsaturated carboxylic acid is 3-butenoic acid, 3-pentenoic acid, 4-pentenoic acid, 2-methyl-3-butenoic acid, 3-hexenoic acid, 4-hexenoic acid, 5-hexenoic acid, 4-methyl- 3-pentenoic acid, 4-methyl-4-pentenoic acid, 3-methyl-3-pentenoic acid, 3-methyl-4-pentenoic acid, 3-ethyl-3-butenoic acid, 2-methyl-3-pentenoic acid, 2-methyl-4-pentenoic acid, 2,2-diethyl-3-butenoic acid, 2,3-diethyl-3-butenoic acid, or 2-ethyl-3-butenoic acid.

As an embodiment of the present invention, the nonionic reactive surfactant may be represented by Formula 1 below.

[Formula 1]

In Formula 1, n may be 7 to 40, 10 to 30, 20 to 30, or 24 to 30. When the oxyethylene repeating unit is less than the above range, heat resistance retention may be reduced, and when it exceeds the above range, poor adhesive base emulsion is caused due to poor emulsification.

On the other hand, the aqueous pressure-sensitive adhesive composition of the present invention is characterized by including the nonionic reactive surfactant, anionic reactive surfactant, acrylate monomer, aqueous solvent, and initiator of the present invention.

In addition, the water-based pressure-sensitive adhesive composition includes 0.01 to 5 parts by weight, 0.05 to 1 part by weight, 0.1 to 0.5 parts by weight of the nonionic reactive surfactant and 0.01 to 5 parts by weight of the anionic reactive surfactant, based on 100 parts by weight of the acrylate monomer. part, 0.05 to 1 part by weight, or 0.1 to 0.5 part by weight. When the content of the nonionic reactive surfactant is less than the above range, heat resistance may be deteriorated, whereas when the content exceeds the above range, emulsification failure may occur. In addition, when the content of the anionic reactive surfactant is less than the above range, emulsion stability may be deteriorated, whereas when the content exceeds the above range, water resistance may be deteriorated.

And, the water-based pressure-sensitive adhesive composition, based on 100 parts by weight of the acrylate monomer, 0.01 to 5 parts by weight, 0.05 to 1 part by weight, 0.1 to 0.5 parts by weight of the initiator and 30 to 200 parts by weight, 40 to 100 parts by weight of the aqueous solvent , or 50 to 80 parts by weight.

The water-based pressure-sensitive adhesive composition according to the present invention has significantly improved adhesiveness through a combination of a nonionic reactive surfactant and an anionic reactive surfactant, and the weight ratio of the nonionic reactive surfactant to the anionic reactive surfactant is 3:7 to 7:3, It is preferably 4:6 to 6:4, or 4.5:5.5 to 5.5:4.5.

In particular, the anionic reactive surfactant, which is one component of the aqueous pressure-sensitive adhesive composition of the present invention, may be a polyoxyethylene-based anionic surfactant having a vinyl group at the end. In particular, the anionic reactive surfactant may have a sulfonic acid or sulfonate functional group. As an example, the anionic reactive surfactant may be represented by Formula 2 below.

[Formula 2]

In Formula 2, R is alkyl, m is 5 to 45, 10 to 40, or 24 to 30, and X is SO ₃ NH ₄ or SO ₃ Na. R may have 1 to 50, 5 to 45, or 10 to 40 carbon atoms.

In addition, the acrylate monomer is selected from the group consisting of acrylic acid (AA), n-butyl acrylate (BAM), 2-ethylhexyl acrylate (2-EHAM), methyl methacrylate (MMA), and mixtures thereof It can be.

More specifically, the acrylate monomer is 1 part by weight of acrylic acid, 20 to 45 parts by weight of 2-ethylhexyl acrylate, 22 to 40 parts by weight, or 24 to 38 parts by weight, n-butyl acrylate 25 to 70 parts by weight , 30 to 65 parts by weight, or 36 to 62 parts by weight, methyl methacrylate may include 8 to 38 parts by weight, 10 to 30 parts by weight, or 12 to 28 parts by weight.

More preferably, the acrylate monomer may include 1 part by weight of acrylic acid, 20 to 30 parts by weight of 2-ethylhexyl acrylate, 55 to 65 parts by weight of n-butyl acrylate, and 9 to 19 parts by weight of methyl methacrylate there is. It was confirmed that the adhesive peel strength can be improved by lowering the content of methyl methacrylate, a hard monomer, and the glass transition temperature of the pressure-sensitive adhesive increases and the adhesive strength increases as the content of n-butyl acrylate increases.

The acrylate monomer is also an acrylic acid alkyl ester or methacrylic acid having 3 or less carbon atoms in an alkyl group such as methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, isopropyl acrylate, and isopropyl methacrylate. alkyl ester; (meth)acrylic acid cyclic alkyl esters such as cyclohexyl (meth)acrylate; Aromatic (meth)acrylic acid esters, such as phenoxymethyl (meth)acrylate and benzyl (meth)acrylate; Aliphatic such as hydroxyalkyl acrylate, hydroxyalkyl methacrylate, polyoxyethylene (meth) acrylate, methoxyethyl acrylate, ethoxymethyl acrylate, glycidyl acrylate, glycidyl methacrylate ( meth)acrylic acid ester; (meth)acrylic acid amides such as acrylamide, methacrylamide, N-methylol acrylamide, N-methoxymethyl acrylamide, and N-methoxybutyl acrylamide; Vinyl methyl ketone, vinyl ethyl ketone, vinyl-n-propyl ketone, vinyl-i-propyl ketone, vinyl-n-butyl ketone, vinyl-i-butyl ketone, vinyl-t-butyl ketone, vinyl phenyl ketone, vinyl benzyl ketone , radically polymerizable monomers containing an aldo group and/or a keto group, such as divinyl ketone and diacetone acrylamide; nitrile group-containing unsaturated compounds such as (meth)acrylonitrile, crotonnitrile, 2-cyanoethyl (meth)acrylate, 2-cyanopropyl (meth)acrylate, and 3-cyanopropyl (meth)acrylate; monovinyl aromatic compounds such as styrene, o-vinyltoluene, m-vinyltoluene, p-vinyltoluene, p-ethylvinylstyrene, α-methylstyrene, and α-fluorostyrene; vinyl halides such as vinyl chloride and vinylidene chloride; Monomers such as vinyl esters such as vinyl propionate may be included, but are not limited thereto.

In addition, the initiator may be ammonium persulfate, sodium metabisulfite, or a mixture thereof, but is not limited thereto. The initiator for the adhesive may be used without limitation, such as a thermal decomposition type initiator or a redox type initiator, and potassium persulfate or sodium hydrogen sulfite may be used.

In addition, the aqueous pressure-sensitive adhesive composition may further include one or more additives selected from the group consisting of a tackifier, an emulsifier, an antifoaming agent, a stabilizer, a pH adjusting agent, a leveling agent, a wetting agent, and a biocide. In addition to the additives and components described above, other additives or components may be further included as appropriate depending on the use of the pressure-sensitive adhesive. The additive may be included in an amount of 0.001 to 30% by weight based on the total composition.

The water-based adhesive composition of the present invention is an adhesive composition having excellent peel strength (adhesive strength) and heat resistance retention, and the peel strength is measured using a 1 kg grip, and the distance (mm) pushed for 1 h with a 1 kg weight at 80 ° C. When the heat resistance retention is measured through, the peel strength may be 1.4 to 2.5, 1.6 to 2.4, or 1.8 to 2.2, and the heat resistance retention may be 1 mm or less, 0.7 mm or less, or 0.4 mm or less.

In addition, the water-based pressure-sensitive adhesive composition of the present invention may have an average particle size of 300 to 620 nm, 400 to 600 nm, or 440 to 580 nm, and a viscosity of 150 to 400 cP, 190 to 350 cP, 200 to 330 cP can be

The particle size of the pressure-sensitive adhesive is influenced by the type and concentration of the surfactant, and shows monomolecularity. If the particle size is less than the above range, particle stability may be deteriorated, whereas if the particle size exceeds the above range, coating properties and adhesive properties may be deteriorated.

In addition, the water-based adhesive may be used for labels, electric/electronic tapes, construction/interior tapes, automotive tapes, or medical adhesives.

On the other hand, the method for producing a nonionic reactive surfactant of the present invention, (a) reacting by adding benzene and an unsaturated carboxylic acid having 4 to 6 carbon atoms to polyoxyethylene alkylphenyl ether; (b) adding a catalyst to the product of step a; (c) obtaining an oily layer after layer separation of the product of step b; and (d) removing the solvent from the oil phase.

The step (a) may be a reaction for 2 to 4 hours at 50 to 70 ℃. The step (b) may be to react at 70 to 90 ℃ for 18 to 30 hours. The catalyst of step (b) may be p-TsOH (para-toluenesulfonic acid). The step (c) may be fractionation by dissolving in dichloromethane (DCM) after removing the solvent and mixing with distilled water (DW) (0.1 to 1 M Na ₂ CO ₃ ). After step (c), the aqueous layer is washed with DCM, and the DCM layer is obtained. Sodium sulfate (Na ₂ SO ₄ ) is added to remove residual water, and sodium sulfate can be removed by filtration under reduced pressure. In the step (d), the solvent may be removed through a rotary evaporator at 40 to 60 °C. A step of drying at 40 to 60 ° C. may be further included after the step (d).

In the above steps (a) to (d), when prepared out of the above range, properties as a surfactant may not be expressed due to overreaction or insufficient reaction.

As an example, the nonionic reactive surfactant may be represented by Formula 1 below, and the polyoxyethylene alkylphenyl ether may be represented by Formula 3 below.

[Formula 1]

[Formula 3]

In Formula 1 and Formula 3, n may be 7 to 40, 10 to 30, 20 to 30, or 24 to 30.

According to the preparation method of the nonionic reactive surfactant of the present invention, a yield of 90% or more can be achieved, and the residues of polyoxyethylene alkylphenyl ether and unsaturated carboxylic acid having 4 to 6 carbon atoms, which are catalysts and reactants, are minimized. can do.

On the other hand, the manufacturing method of the water-based pressure-sensitive adhesive of the present invention, (A) an aqueous solvent, an anionic reactive surfactant, a nonionic reactive surfactant formed by the reaction of polyoxyethylene alkylphenyl ether with an unsaturated carboxylic acid having 4 to 6 carbon atoms, and Mixing acrylic acid, (B) mixing an acrylate monomer with the mixture of step (A) to form a pre-emulsion, (C) mixing an initiator and sodium metabisulfite with a portion of the pre-emulsion, (D) dropping the remaining pre-emulsion into the mixture of step (C), and (E) neutralizing. Referring to FIG. 7 , each step will be described in detail below.

First, step (A) is a step of mixing an aqueous solvent such as water, an anionic reactive surfactant, a nonionic reactive surfactant formed by the reaction of polyoxyethylene alkylphenyl ether with an unsaturated carboxylic acid having 4 to 6 carbon atoms, and acrylic acid.

More specifically, step (A) includes 10 to 40 parts by weight, 20 to 34 parts by weight, or 22 to 30 parts by weight of an aqueous solvent, 0.01 to 5 parts by weight of the nonionic reactive surfactant, 0.05 parts by weight, based on 1 part by weight of acrylic acid. to 1 part by weight, 0.1 to 0.5 parts by weight, and 0.01 to 5 parts by weight, 0.05 to 1 part by weight, or 0.1 to 0.5 parts by weight of the anionic reactive surfactant may be mixed and stirred.

Next, step (B) is a step of forming a pre-emulsion by mixing and stirring the acrylate monomer in the mixture of step (A). Through this, a pre-emulsion may be formed. When a milky emulsion is formed, it can be stirred for 20 to 40 minutes.

In step (B), dodecylmercaptan may be added in an amount of 0.01 to 0.1 parts by weight, 0.02 to 0.08 parts by weight, or 0.03 to 0.07 parts by weight based on 100 parts by weight of the acrylate monomer. Acrylate monomer is 0.01 to 5 parts by weight, 0.05 to 1 part by weight, 0.1 to 0.5 parts by weight of the nonionic reactive surfactant and 0.01 to 5 parts by weight, 0.05 to 0.05 parts by weight of the anionic reactive surfactant, based on 100 parts by weight of the acrylate monomer. It is added to include 1 part by weight and 0.1 to 0.5 parts by weight.

The acrylate monomer may be selected from the group consisting of acrylic acid, n-butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, and mixtures thereof.

Next, step (C) is a step of mixing an initiator and sodium metabisulfite with a portion of the pre-emulsion. The initiator may be ammonium persulfate (APS). This may be for a preliminary reaction.

More specifically, step (C) includes (C-1) introducing a mixture of an aqueous solvent and an initiator into a portion of the pre-emulsion and stirring it, and (C-2) the product of step (C-1), the aqueous solvent and an initiator, and sodium metabisulfite (SMBS) sequentially added to a reaction vessel heated to 70 to 90 ° C., followed by stirring.

Next, step (D) is a step of adding the remaining pre-emulsion dropwise to the mixture of step (C). The dropping may be carried out for 1 to 3 hours or 1.5 to 2.5 hours, and after dropping, an initiator or a mixture of an initiator and an aqueous solvent may be additionally added. Thereafter, the temperature may be maintained at 32 to 35 °C.

Next, step (E) is a step of neutralization, and a basic solution such as a mixture of an aqueous solvent and ammonia water may be introduced into the product of step (D) to neutralize to a weak acid (pH 5 to 6). After neutralization, it can be filtered to obtain an aqueous pressure-sensitive adhesive composition.

Hereinafter, embodiments of the present invention will be described.

[Example]

Preparation Example 1: Preparation of nonionic reactive surfactant (1) - KR-DDP-10

100 g (0.141 mol) of emulsifier polyoxyethylene (10) dodecylphenyl ether (DDP_10), 200 ml of Benzene, and 24.28 g (0.282 mol) of 3-Butenoic acid were added and mixed in a 1000 mL cylindrical three-necked flask at 60 ° C. Reacted for 3 h. After that, 1.453 g (0.00846 mol) of catalyst p -TsOH was added and reacted at 80 °C for 24 h. Next, the solvent was removed at 50 °C using a rotary evaporator, dissolved in 500 ml of DCM, and then put into a 1000 ml separatory funnel. 500 ml of 0.5 M Na ₂ CO ₃ solution was put into a 1000 ml separatory funnel and physically shaken to mix the two layers. After 12 h, the DCM layer was first obtained, and 500 ml of DCM was added to obtain the product remaining in the DW layer, followed by second fractionation (3 h). To obtain a DCM layer and remove residual water, 5 g of Na ₂ SO ₄ was added and stirred at room temperature for 1 h. After that, the remaining Na ₂ SO ₄ was removed using a G3 filter, the solvent was removed at 50 ° C using a Rotary Evaporator, and the solvent was secondarily removed at 50 ° C using a Vacuum Oven, and the following chemical formula (n = 10) of the nonionic reactive surfactant was prepared.

Preparation Example 2: Preparation of nonionic reactive surfactant (2) - KR-DDP-20

100 g (0.0875 mol) of emulsifier polyoxyethylene (20) dodecylphenyl ether (DDP_20), 200 ml of Benzene, and 15.06 g (0.175 mol) of 3-Butenoic acid were added and mixed in a 1000 mL cylindrical three-necked flask at 60 ° C. Reacted for 3 h. After that, 0.859 g (0.005 mol) of catalyst p -TsOH was added and reacted at 80 °C for 24 h. Next, the solvent was removed at 50 °C using a rotary evaporator, dissolved in 500 ml of DCM, and then put into a 1000 ml separatory funnel. 500 ml of 0.5 M Na ₂ CO ₃ solution was put into a 1000 ml separatory funnel and physically shaken to mix the two layers. After 12 h, the DCM layer was first obtained, and 500 ml of DCM was added to obtain the product remaining in the DW layer, followed by second fractionation (3 h). To obtain a DCM layer and remove residual water, 5 g of Na ₂ SO ₄ was added and stirred at room temperature for 1 h. After that, the remaining Na ₂ SO ₄ was removed using a G3 filter, the solvent was removed at 50 ° C using a Rotary Evaporator, and the solvent was secondarily removed at 50 ° C using a Vacuum Oven, and the following chemical formula (n = 20) of the nonionic reactive surfactant was prepared.

Preparation Example 3: Preparation of nonionic reactive surfactant (3) - KR-DDP-30

100 g (0.064 mol) of emulsifier polyoxyethylene (30) dodecylphenyl ether (DDP_30), 200 ml of Benzene, and 11.02 g (0.128 mol) of 3-Butenoic acid were added and mixed in a 1000 mL cylindrical three-necked flask at 60 ° C. Reacted for 3 h. After that, 0.653 g (0.0038 mol) of catalyst p -TsOH was added and reacted at 80 °C for 24 h. Next, the solvent was removed at 50 °C using a rotary evaporator, dissolved in 500 ml of DCM, and then put into a 1000 ml separatory funnel. 500 ml of 0.5 M Na ₂ CO ₃ solution was put into a 1000 ml separatory funnel and physically shaken to mix the two layers. After 12 h, the DCM layer was first obtained, and 500 ml of DCM was added to obtain the product remaining in the DW layer, followed by second fractionation (3 h). To obtain a DCM layer and remove residual water, 5 g of Na ₂ SO ₄ was added and stirred at room temperature for 1 h. After that, the remaining Na ₂ SO ₄ was removed using a G3 filter, the solvent was removed at 50 ° C using a Rotary Evaporator, and the solvent was secondarily removed at 50 ° C using a Vacuum Oven, and the following chemical formula (n = 30) of the nonionic reactive surfactant was prepared.

Test Example 1: Confirmation of Composite

1H-NMR and 13C-NMR analyzes were performed on the surfactants prepared in Preparation Examples 1 to 3.

1, 3, and 5 are ¹ H-NMR analysis results for the surfactants prepared in Preparation Examples 1 to 3, respectively, and the synthesis was confirmed by the generation and increase of f peak ( x / 2.00 ), and fraction neutralization After that, it was confirmed that the p -TsOH peak disappeared. In addition, FIGS. 2, 4, and 6 show the results of ¹³ C-NMR analysis of the surfactants prepared in Preparation Examples 1 to 3, respectively, confirming that the peaks of the remaining 3-butenoic acid and catalyst p -TsOH disappear. did Through this, it can be seen that the desired surfactant was synthesized.

Example 1: Preparation of water-based adhesive-EMU-KR-DDP-10-I

After putting 34.83 phr of D.W in a 4-necked round bottom flask, it was heated to 80° C. (to create a polymerization atmosphere). After adding 26.29 phr of D.W, 0.35 phr of anionic reactive surfactant (SR-3025, ADEKA Co.), 0.35 phr of nonionic reactive surfactant prepared in Preparation Example 1, and 1.00 phr of acrylic acid (AA) to a beaker, use a mechanical stirrer and stirred. 2-ethylhexyl acrylate (2-EHAM) 37.50 phr, n-butyl acrylate (BAM) 37.50 phr, methyl methacrylate (MMA) 24.00 phr, dodecylmer After adding 0.044 phr of dodecyl mercaptan to the beaker, the mixture was stirred. A milky pre-emulsion was formed and stirred for 30 minutes. After mixing 2.78 phr of D.W and 0.28 phr of ammonium persulfate (APS) in a beaker, it was added to the pre-emulsion and stirred for 5 minutes.

1.39 phr of the resulting pre-emulsion, a mixture of 0.44 phr of D.W and 0.017 phr of APS, and 0.009 phr of sodium metabisulfite (SMBS) were sequentially added to a four-necked round bottom flask and stirred for 5 minutes. Thereafter, the remaining pre-emulsion was added to the cylindrical dropping panel and then dropped for 2 h. After the dropping was completed, 0.17 phr of D.W and 0.053 phr of APS were additionally added, and tap water was replaced in the water-bath to maintain at 32-35 ° C. A mixture of 0.26 phr of D.W. and 0.26 phr of 25% ammonia water was added thereto to neutralize with weak acidity, and after 10 minutes, the mixture was filtered through a filter cloth.

Example 2: Preparation of water-based adhesive-EMU-KR-DDP-10-II

After putting 34.83 phr of D.W in a 4-necked round bottom flask, it was heated to 80° C. (to create a polymerization atmosphere). After adding 26.29 phr of D.W, 0.35 phr of anionic reactive surfactant (SR-3025, ADEKA Co.), 0.35 phr of nonionic reactive surfactant prepared in Preparation Example 1, and 1.00 phr of acrylic acid (AA) to a beaker, use a mechanical stirrer and stirred. 2-ethylhexyl acrylate (2-EHAM) 25.50 phr, n-butyl acrylate (BAM) 59.50 phr, methyl methacrylate (MMA) 14.00 phr, dodecylmer After adding 0.044 phr of dodecyl mercaptan to the beaker, the mixture was stirred. A milky pre-emulsion was formed and stirred for 30 minutes. After mixing 2.78 phr of D.W and 0.28 phr of ammonium persulfate (APS) in a beaker, it was added to the pre-emulsion and stirred for 5 minutes.

1.39 phr of the resulting pre-emulsion, a mixture of 0.44 phr of D.W and 0.017 phr of APS, and 0.009 phr of sodium metabisulfite (SMBS) were sequentially added to a four-necked round bottom flask and stirred for 5 minutes. Thereafter, the remaining pre-emulsion was added to the cylindrical dropping panel and then dropped for 2 h. After the dropping was completed, 0.17 phr of D.W and 0.053 phr of APS were additionally added, and tap water was replaced in the water-bath to maintain at 32-35 ° C. A mixture of 0.26 phr of D.W. and 0.26 phr of 25% ammonia water was added thereto to neutralize with weak acidity, and after 10 minutes, the mixture was filtered through a filter cloth.

Example 3: Preparation of water-based adhesive-EMU-KR-DDP-20-I

It was prepared in the same manner as in Example 1, but the nonionic reactive surfactant prepared in Preparation Example 2 was used instead of the nonionic reactive surfactant prepared in Preparation Example 1.

Example 4: Preparation of water-based adhesive-EMU-KR-DDP-20-II

It was prepared in the same manner as in Example 2, but the nonionic reactive surfactant prepared in Preparation Example 2 was used instead of the nonionic reactive surfactant prepared in Preparation Example 1.

Example 5: Preparation of water-based adhesive--EMU-KR-DDP-30-I

It was prepared in the same manner as in Example 1, but the nonionic reactive surfactant prepared in Preparation Example 3 was used instead of the nonionic reactive surfactant prepared in Preparation Example 1.

Example 6: Preparation of water-based adhesive-EMU-KR-DDP-30-II

It was prepared in the same manner as in Example 2, but the nonionic reactive surfactant prepared in Preparation Example 3 was used instead of the nonionic reactive surfactant prepared in Preparation Example 1.

Comparative Example 1: Comparative preparation of water-based pressure sensitive adhesive (1)

It was prepared in the same manner as in Example 1, but an anionic surfactant (SLS, Sodium lauryl sulfate) was used instead of the anionic reactive surfactant (SR-3025, ADEKA Co.) and the nonionic reactive surfactant prepared in Preparation Example 1.

Comparative Example 2: Comparative preparation of water-based adhesive (2)

It was prepared in the same manner as in Example 1, but a nonionic reactive surfactant (ER-10, ADEKA Co.) was used instead of the anionic reactive surfactant (SR-3025, ADEKA Co.) and the nonionic reactive surfactant prepared in Preparation Example 1 used

Comparative Example 3: Comparative preparation of water-based pressure sensitive adhesive (3)

Prepared in the same manner as in Example 1, but using the nonionic reactive surfactant prepared in Preparation Example 1 alone instead of the anionic reactive surfactant (SR-3025, ADEKA Co.) and the nonionic reactive surfactant prepared in Preparation Example 1 used

Comparative Example 4: Comparative preparation of water-based pressure sensitive adhesive (4)

Prepared in the same manner as in Example 1, but using the anionic reactive surfactant (SR-3025, ADEKA Co.) instead of the anionic reactive surfactant (SR-3025, ADEKA Co.) and the nonionic reactive surfactant prepared in Preparation Example 1 used alone.

Test Example 2: Analysis of physical properties of water-based pressure-sensitive adhesive

For the water-based pressure-sensitive adhesives prepared according to Examples 1 to 6 and Comparative Examples 1 to 4, NV and conversion rates defined as follows were calculated after drying the remaining distilled water and monomers in an oven at 120 ° C.

NV = (W _d / W _s ) X 100 (%)

Conversion rate = (W _d / W _s T _s ) X 100 (%)

W _d = sample weight of after drying

W _s = sample weight of before drying

T _s = Ideal solid content (%)

In addition, referring to the measurement method of Table 3 below, peel strength was measured using a 1 kg grip, and heat resistance retention was measured through a distance (mm) pushed for 1 h with a 1 kg weight attached at 80 ° C. In addition, pH was measured using a pH meter, and particle size was measured using a zetasizer. In addition, it was observed whether layer separation occurred due to lack of surfactant during pre-emulsion preparation, and the results are shown in Tables 1 and 2 below.

Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 solid content 59.92 59.9 58.11 59.31 59.3 59.92 peel strength
(kg _f /inch) 1.851 1.837 1.856 1.817 1.774 2.041 heat resistance
(mm) 0.2 0.4 0.7 0.2 0.2 x pH 5.73 5.64 5.90 5.7 5.71 5.69 viscosity
(cP, Torque) 247.33, 6.12 303.03, 7.66 332.12, 7.85 238.59, 6.02 203.09, 5.30 217.23, 5.63 particle size
(nm) 486.4 ± 28.91 491.3 ± 17.50 447.3 ± 20.96 474.3 ± 29.49 496.8 ± 19.83 564.0 ± 42.92 NV(%) 59.92 59.31 59.9 59.3 58.11 59.92 HLB 11.43 11.43 14.54 14.54 16 16 Conversion rate (%) 97.81 96.81 97.77 96.792 94.85 97.804 Layer separation during pre_emulsion X X O X X X

solid content
(%) conversion rate
(%) peel strength
(kgf/inch) heat resistance
(mm) viscosity
(cP) particle size
(nm) Comparative Example 1 60.81 99.81 2.974 15 minutes later
Separation of test piece 84.24 Comparative Example 2 A small amount of layer separation occurs during the pre-emulsion process,
An adhesive emulsion was prepared, but was waxed due to poor emulsion stability. Comparative Example 3 Layer separation occurs during the pre-emulsion process Comparative Example 4 60.1 97.52 1.38 1.0 181.8 625

main
performance indicator sample definition Measurement method (standards, environment, result calculation, etc.) solid content % The KS M 6638 standard, which is a general test method for adhesives specified in the Korean Industrial Standards, was carried out. After weighing 0.5 g of the sample on an aluminum plate to four decimal places, drying in an oven at 150 ° C for 30 minutes and drying again Calculated as a percentage (%) by dividing the dried weight, which is the value minus the weight of each aluminum dish by measuring the weight of the ordered aluminum dish, by the weight before drying peel strength kg/25mm Prepare a 50mm wide and 150mm long painted steel plate or SUS-304 cleaned with ethanol or isopropyl alcohol as an adherend, attach it to the adherend with a width of 25mm, and press it with a roller with a specified load (2kg). Adhesion was measured at room temperature at a peel angle of 180° and a peel speed of 300 mm/min. Heat resistance cohesion (1kg×1hr) ℃ - After attaching the test piece to ASTM D-3654 stainless steel (SUS304) with an adhesive area of 25mm×25mm according to the standard, leave it for 60 minutes at a temperature of 23±2℃ and a relative humidity of 50±5% RH.
- Apply a 1kg load and measure the distance the tape is pushed under the condition of temperature 80℃ and time 1hr viscosity cps/25℃ The viscosity of the aqueous acrylic pressure-sensitive adhesive base emulsion was measured using a viscometer (DV-EViscometer/LV, Brookfield Ametek). Viscosity is evaluated for stability by measuring the initial viscosity and the viscosity 4 weeks after manufacture. particle size nm A particle size distribution analyzer (Zetasizer Nano ZS90, Malvern) was used to determine the average particle size of the aqueous acrylic adhesive base emulsion. For analysis sample preparation, after diluting 0.1g of the adhesive base emulsion in 50mL distilled water, the particle size was measured as an average value, and for the accuracy of the measured value, each measurement was performed more than 5 times and expressed as an average value.

2-EHAM: BAM: MMA: AA = 25.5: 59.5: 14: In the case of Example 6 in which the number of moles of EO was 30, peel strength and heat resistance (not pushed at all) were found to be very good. The physical properties of the adhesive were greatly affected by the monomer composition, and the adhesive peel strength tended to decrease slightly as the content of MMA, a hard monomer, increased. In addition, it was confirmed that the higher the BAM content, the higher the glass transition temperature of the pressure-sensitive adhesive and the higher the adhesive strength.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various modifications without departing from the gist of the present invention. Of course it is possible. Therefore, the scope of the present invention should not be construed as being limited to the above embodiments, and should be defined by not only the claims to be described later, but also those equivalent to these claims.

Claims (9)

A nonionic reactive surfactant formed by the reaction of polyoxyethylene alkylphenyl ether with an unsaturated carboxylic acid having 4 to 6 carbon atoms. An aqueous pressure-sensitive adhesive composition comprising the nonionic reactive surfactant of claim 1, an anionic reactive surfactant, an acrylate monomer, an aqueous solvent, and an initiator. The method of claim 2,
The anionic reactive surfactant is a polyoxyethylene-based anionic surfactant having a vinyl group at the terminal, characterized in that, the water-based pressure-sensitive adhesive composition. The method of claim 2,
The acrylate monomer is characterized in that selected from the group consisting of acrylic acid, n-butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, and mixtures thereof, the aqueous pressure-sensitive adhesive composition. The method of claim 2,
The initiator is an aqueous pressure-sensitive adhesive composition, characterized in that ammonium persulfate, sodium metabisulfite, or a mixture thereof. The method of claim 2,
The water-based pressure-sensitive adhesive composition comprises at least one additive selected from the group consisting of a tackifier, an emulsifier, an antifoaming agent, a stabilizer, a pH adjusting agent, a leveling agent, a wetting agent, a biocide, and mixtures thereof. , water-based pressure-sensitive adhesive composition. (a) reacting by adding benzene and an unsaturated carboxylic acid having 4 to 6 carbon atoms to polyoxyethylene alkylphenyl ether;
(b) adding a catalyst to the product of step a;
(c) obtaining an oily layer after layer separation of the product of step b; and
(d) removing the solvent from the oil phase; method for producing a non-ionic reactive surfactant, including. The method of claim 7,
The catalyst is para-toluenesulfonic acid, a method for producing a non-ionic reactive surfactant. (A) mixing an aqueous solvent, an anionic reactive surfactant, a nonionic reactive surfactant formed by the reaction of polyoxyethylene alkylphenyl ether with an unsaturated carboxylic acid having 4 to 6 carbon atoms, and acrylic acid;
(B) forming a pre-emulsion by mixing an acrylate monomer with the mixture of step (A);
(C) mixing an initiator and sodium metabisulfite with a portion of the pre-emulsion;
(D) dropping the remaining pre-emulsion into the mixture of step (C), and
(E) a method for producing a water-based pressure-sensitive adhesive comprising the step of neutralizing.

Images