JPH11286650A - Low temperature-sensitive thickener composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a thickener compsn. which has both a high thickening ability and a low temp. sensitiveness by using a modified hydrophilic polymer having a specified structure and physical properties. SOLUTION: A hydrophilic polymer of the formula having both molecular ends modified with hydrophobic groups and having a cloud point of an 0.5% aq. soln. in the range of 60-120 deg.C is used. In the formula, R1 and R2 are each 6-36C alkyl, cycloalkyl, alkenyl, cycloalkenyl, aryl, alkaryl, aralkyl, or the like; X1 to X4 are each ester, carbonyl, thiocarbonyl, amide, urethane, ether, or the like; A1 O and A2 O are each 2-4C oxyalkylene; Y is a group having a strongly hydrophilic group; m is 10-500; n is 1-20; and p is 10-500. A carboxyl or carboxylate group and a sulfo or sulfonate group are pref. as the strongly hydrophilic group of Y. The thickener compsn. in an amt. of 0.01-10 wt.% is added to an aq. emulsion (coating material).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a thickener. More specifically, the present invention relates to a thickener composition useful for an aqueous emulsion having a low temperature sensitivity, an aqueous emulsion paint, and the like.

[0002]

2. Description of the Related Art Hitherto, as a thickener, a compound in which both ends of a polyalkylene glycol are modified with a hydrophobic group is known. (Japanese Patent Laid-Open No. 58-213074, Japanese Patent Publication No. 1-552)
No. 92, Tokuhei 3-52766)

[0003]

However, such conventional compounds have a drawback that the thickening action greatly changes with a temperature change in a practical temperature range (0 to 50 ° C.). there were. In addition, in the case of those having little change in the thickening action due to temperature change (low temperature sensitivity), the fact was that the thickening action itself was extremely small. As described above, the conventional technology has a problem that it is impossible to achieve both viscosity increase and low temperature sensitivity, and it is an object of the present invention to create a thickener having both viscosity increase and low temperature sensitivity.

[0004]

Means for Solving the Problems The present inventors have conducted intensive studies to overcome the above-mentioned drawbacks, and as a result, have found that a compound having a specific structure and physical properties has both high viscosity and low temperature sensitivity. The invention of the present thickener composition has been reached.

That is, the present invention relates to a hydrophilic polymer modified with a hydrophobic group at both ends represented by the general formula (1) (Compound A), wherein the 0.5% aqueous solution has a cloud point of 60 to 120 ° C. It is a characteristic low-temperature-sensitive thickener composition. R1-X1-[(A1O) _m- X2-Y-X3] _n- (A2O) _p -X4-R2 (1) wherein R1 and R2 are an alkyl group having 6 to 36 carbon atoms, a cycloalkyl group, A functional group selected from the group consisting of alkenyl, cycloalkenyl, aryl, alkylaryl, arylalkyl and arylalkylaryl; X1, X2, X3 and X4 are ester groups; A carbonyl group, a thiocarbonyl group, an amide group, a urethane group, a ureylene group, an ether group, a thioether group and an imino group;
O and A2O are oxyalkylene groups having 2 to 4 carbon atoms, Y is a functional group having a strongly hydrophilic functional group, and m is 1
An integer of 0 to 500, n is an integer of 1 to 20,
p is an integer of 10 to 500. ]

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION In the general formula (1) of the present invention, R1,
R2 represents an alkyl group having 6 to 36 carbon atoms, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an aryl group,
Alkyl aryl group, aryl alkyl group and aryl
A hydrophobic functional group selected from the group consisting of alkylalkyl aryl groups.

As the alkyl group having 6 to 36 carbon atoms, hexyl group, isohexyl group, heptyl group, octyl group,
2-ethylhexyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, isotridecyl group,
Examples include a myristyl group, a palmityl group, a stearyl group, and an isostearyl group.

Examples of the cycloalkyl group having 6 to 36 carbon atoms include a cyclohexyl group, a cycloheptyl group, a methylcyclopentyl group, a methylcyclohexyl group, and a methylcycloheptyl group.

The alkenyl group having 6 to 36 carbon atoms includes
Hexenyl group, hexadienyl group, heptenyl group, octenyl group, nonenyl group, decenyl group, undecenyl group,
A dodecenyl group, a tetradecenyl group, an oleyl group and the like.

The cycloalkenyl group having 6 to 36 carbon atoms includes 2,4-cyclohexadienyl group, cyclohexenyl group, cycloheptenyl group, methylcyclopentenyl group, methylcyclohexenyl group, methylcycloheptenyl group and the like. .

Examples of the aryl group having 6 to 36 carbon atoms include a phenyl group, an α-naphthyl group and a β-naphthyl group.

Examples of the alkyl aryl group having 6 to 36 carbon atoms include toluyl, xylyl, cumenyl, mesityl, ethylphenyl, propylphenyl, butylphenyl, pentylphenyl, hexylphenyl,
Examples include a heptylphenyl group, an octylphenyl group, a nonylphenyl group, a decylphenyl group, an undecylphenyl group, a dodecylphenyl group, a tridecylphenyl group, and the like.

Examples of the arylalkyl group having 6 to 36 carbon atoms include a benzyl group and a benzhydryl group.

C6 to C36 arylalkylaryl
Examples of the phenyl group include a styrenated phenyl group.

Of these, a hydrophobic functional group having 8 to 26 carbon atoms is preferred, and a hydrophobic functional group having 12 to 26 carbon atoms is more preferred.
4 is a hydrophobic functional group. When the number of carbon atoms is less than 6, the thickening effect is small, and when the number of carbon atoms exceeds 36, the temperature sensitivity is increased. R
1 and R2 may be the same or different.

In the general formula (1) of the present invention, X1, X2, X
3, X4 is a functional group selected from the group consisting of ester groups, carbonyl groups, thiocarbonyl groups, amide groups, urethane groups, ureylene groups, ether groups, thioether groups and imino groups. Of these, an ester group, a urethane group, an ether group and a thioether group are preferred, and a urethane group and an ether group are more preferred.
X1, X2, X3 and X4 may be the same or different.

A 1 O and A 2 O in the general formula (1) of the present invention are oxyalkylene groups having 2 to 4 carbon atoms. 2 carbon atoms
Examples of the oxyalkylene group 4 include an oxyethylene group, an oxypropylene group and an oxybutylene group. Of these, an oxyethylene group is preferred. A1O and A2O may be the same kind or different kinds of combinations. (A ₁ O) _m and (A ₂ O) _p may be those obtained by connecting two or more oxyalkylene groups in a block or at random.

Y in the general formula (1) of the present invention is a functional group having a strongly hydrophilic functional group. As the strong hydrophilic functional group,
Nonionic strong hydrophilic functional groups and ionic strong hydrophilic functional groups are exemplified. Examples of the ionic strong hydrophilic functional group include an anionic strong hydrophilic functional group and a cationic strong hydrophilic functional group.

Examples of the nonionic strong hydrophilic functional group include a hydroxyl group and an amine oxide group.

The anionic strong hydrophilic functional groups include carboxylic acid (salt) group, sulfonic acid (salt) group, phosphoric acid (salt)
Groups, sulfate (salt) groups, and phosphate (salt) groups.

As the salt of the anionic strong hydrophilic functional group,
Alkali metal salts (such as lithium, sodium and potassium salts), alkaline earth metal salts (such as calcium and magnesium salts), ammonium salts, alkanolamine salts (such as monoethanolamine, diethanolamine, and triethanolamine salts). can give.

The cationic strong hydrophilic functional groups include
Hydrochloride of primary amine, formate of primary amine, acetate of primary amine, hydrochloride of secondary amine, formate of secondary amine, acetate of secondary amine, tertiary amine Hydrochloride,
Functional groups such as tertiary amine formate, tertiary amine acetate, quaternary ammonium chloride, quaternary ammonium bromide and quaternary ammonium sulfate are exemplified.

Among the strong hydrophilic functional groups, an anionic strong hydrophilic functional group is preferred. Among the anionic strong hydrophilic functional groups, a carboxylic acid (salt) group and a sulfonic acid (salt) group are more preferable.

In the general formula (1) of the present invention, m is usually from 10 to
It is an integer of 500. Preferably 20 to 400,
More preferably, it is 30 to 300. If it is less than 10 or more than 500, the viscosity increases.

In the general formula (1) of the present invention, n is usually from 1 to 2.
It is an integer of 0. Preferably it is 5-15. If it exceeds 20, the viscosity increases.

In the general formula (1) of the present invention, p is usually 10 to 10.
It is an integer of 500. Preferably 20 to 400,
More preferably, it is 30 to 300. If it is less than 10 or more than 500, the viscosity increases.

The cloud point of the compound A of the present invention is usually from 60 to 12
0 ° C., preferably 70 to 110 ° C., and more preferably 80 to 100 ° C. When the cloud point is lower than 60 ° C., the temperature sensitivity increases, and when the cloud point exceeds 120 ° C., the viscosity increases. Here, the cloud point is a value measured by the following measuring method.

A 0.5% by weight aqueous solution of Compound A was prepared as a measurement sample. The measurement sample is placed in a capillary tube, sealed, attached to a thermo-sensitive bulb portion of a thermometer, and placed in an oil bath and heated. The temperature at which the measurement sample becomes cloudy is defined as the cloud point.

As a method for synthesizing the compound A of the present invention, a method generally used (chemical reaction) can be used. For example, (1) a method in which a strong hydrophilic functional group is introduced in advance into the oxyalkylene group portion, and then For example, polyethylene glycol and 1,3-dichloro-2-carboxypropane are reacted in the presence of sodium methylate, and then the reaction product is esterified with stearic acid to convert both ends. A method of modifying a hydrophobic group, (2) a method of simultaneously introducing a strongly hydrophilic functional group into an oxyalkylene group portion and modifying a hydrophobic group at both ends, for example, octadecyl isocyanate, polyethylene glycol, A method of simultaneously reacting carboxytetramethylene diisocyanate in the presence of di-n-butyltin dilaurate;
(3) A method of introducing a strongly hydrophilic functional group after modifying both ends with a hydrophobic group in advance, for example, addition polymerization of ethylene oxide to higher alcohol in the presence of potassium hydroxide, followed by 2-carboxytetracarboxylic acid A method of reacting methylene diisocyanate with di-n-butyltin dilaurate in the presence of methylene diisocyanate.

By using an anionic and / or nonionic surfactant in combination with the thickener composition of the present invention,
Further, the temperature sensitivity can be reduced.

The amount of the thickener composition of the present invention to be added (in terms of solid content) is preferably from 0.01 to 10 with respect to the solid content of the emulsion in the aqueous emulsion and the aqueous emulsion paint.
%, Preferably 0.05 to 5%. If it is less than 0.01%, the viscosity increases, and if it exceeds 10%, the temperature sensitivity increases.

As a method for adding the thickener composition of the present invention, the thickener composition may be directly added to an aqueous emulsion or an aqueous emulsion paint, or may be diluted with water or a solvent before being added.

Aqueous emulsions in which the thickener composition of the present invention can be used include acrylic resin emulsions, vinyl acetate resin emulsions, vinyl chloride resin emulsions, acrylic styrene resin emulsions, and the like.
Silicone resin emulsion, urethane resin emulsion, epoxy resin emulsion, fluororesin emulsion, SB latex, SBR latex, ABS latex, NBR latex, CR latex and the like can be mentioned.

The water-based emulsion paint in which the thickener composition of the present invention can be used usually comprises a water-based emulsion, a pigment, water and additives. Aqueous emulsions include acrylic resin emulsions, vinyl acetate resin emulsions, vinyl chloride resin emulsions, acrylic styrene resin emulsions, silicone resin emulsions, urethane resin emulsions, epoxy resin emulsions,
A fluororesin emulsion. Examples of the pigment include inorganic pigments such as calcium carbonate, titanium oxide, satin white, barium sulfate, talc, zinc oxide, gypsum, silica, and ferrite, and organic pigments such as polystyrene plastic pigment.

The thickener composition of the present invention is preliminarily mixed with an antioxidant, an ultraviolet absorber, a water-proofing agent, a preservative / antifungal agent, a defoamer, a dispersant, a deodorant, a fragrance, a dye and the like. May be used.

Hereinafter, the present invention will be further described with reference to examples, but the present invention is not limited to these examples. Example,
Comparative examples are shown in Table 1.

[0037]

[Table 1]

[0038] X1, X2, X3, X4;: Ester group: Urethane group: Ether group A1O, A2O; oxyethylene group

The performance of Examples 1 to 7 and Comparative Examples 1 to 6 was evaluated by the following methods. The results are shown in Tables 2 and 3.

Evaluation Example 1: Thickening with an aqueous emulsion,
100 parts by weight of an acrylic emulsion [commercial product: concentration 48%], an antifoaming agent [Dehydran 162, manufactured by Henkel KGaA]
0] An aqueous emulsion having a solid content of 43% was prepared by mixing 0.1 parts by weight and 0.5 part by weight of the thickener. With the above composition, the mixture was stirred at 3000 rpm for 5 minutes with a table homogenizer, and then allowed to stand for 12 hours. Thereafter, the temperature of the mixture was adjusted to a predetermined temperature (2, 25, 40 ° C.) for 2 hours.
The viscosity at rpm (BM type viscometer manufactured by Tokyo Keiki Co., Ltd.) was measured. Thickening: At each temperature of 2, 25, and 40 ° C., the higher the viscosity, the better the viscosity as compared with the case where no thickener is added. Temperature sensitivity: The smaller the ratio of the viscosity at 2 ° C to the viscosity at 40 ° C, the lower the temperature sensitivity.

[0041]

[Table 2]

Evaluation Example 2: Evaluation of Viscosity and Temperature Sensitivity with Water-Based Emulsion Paint Titanium Dioxide [JR-600A, manufactured by Teika Co., Ltd.] 35
0 parts by weight, 100 parts by weight of calcium carbonate [manufactured by Sankyo Flour Milling Co., Ltd., Escalon # 2000], 4 parts by weight of dispersant [manufactured by San Nopco Co., Ltd., Nopco Space 44-C], defoaming agent [manufactured by Henkel KGAA, Dehydran 1620] 3 parts by weight, preservative [Nopcoside SN-, manufactured by San Nopco Co., Ltd.]
215] 2.4 parts by weight, 100 parts by weight of water, 605 parts by weight of emulsion for gloss paint (acrylic), 30 parts by weight of propylene glycol, film-forming aid [Texanol, manufactured by Eastman Chemical Company] An aqueous emulsion paint having a composition of 15 parts by weight and 15 parts by weight of a thickener was prepared. After that, the prepared paint is heated to a predetermined temperature (2, 25, 40 ° C)
After controlling the temperature for 2 hours, the viscosity (BM type viscometer manufactured by Tokyo Keiki Co., Ltd.) at 60 rpm was measured. Thickening: At each temperature of 2, 25, and 40 ° C., the higher the viscosity, the better the viscosity as compared with the case where no thickener is added. Temperature sensitivity: The smaller the ratio of the viscosity at 2 ° C to the viscosity at 40 ° C, the lower the temperature sensitivity.

[0043]

[Table 3]

[0044]

The effects of the present invention are to provide a novel thickener having both a thickening property and a low temperature sensitivity, and an aqueous emulsion and an aqueous emulsion paint containing the thickener. The water-based emulsion paint containing the thickener of the present invention has the characteristics that the temperature dependence of the paint viscosity is small, the coating workability is excellent throughout the year, and the paint is less dripping in summer.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI // C09D 7/02 C09D 7/02

Claims (6)

[Claims] 1. A hydrophilic polymer (compound A) modified with a hydrophobic group at both ends represented by the general formula (1), wherein a 0.5% aqueous solution has a cloud point of 60 to 120 ° C. Low temperature-sensitive thickener composition. R1-X1-[(A1O) _m- X2-Y-X3] _n- (A2O) _p -X4-R2 (1) wherein R1 and R2 are an alkyl group having 6 to 36 carbon atoms, a cycloalkyl group, A functional group selected from the group consisting of alkenyl, cycloalkenyl, aryl, alkylaryl, arylalkyl and arylalkylaryl; X1, X2, X3 and X4 are ester groups; A carbonyl group, a thiocarbonyl group, an amide group, a urethane group, a ureylene group, an ether group, a thioether group and an imino group;
O and A2O are oxyalkylene groups having 2 to 4 carbon atoms, Y is a functional group having a strongly hydrophilic functional group, and m is 1
An integer of 0 to 500, n is an integer of 1 to 20,
p is an integer of 10 to 500. ] 2. The thickener composition according to claim 1, wherein the strongly hydrophilic functional group of Y is an ionic functional group. 3. The thickener composition according to claim 2, wherein the ionic functional group is a carboxylic acid (salt) group. 4. The thickener composition according to claim 2, wherein the ionic functional group is a sulfonic acid (salt) group. 5. An aqueous emulsion containing 0.01 to 10% by weight of the thickener composition according to claim 1. 6. An aqueous emulsion paint containing the thickener composition according to claim 1 in an amount of 0.01 to 10% by weight.