JPH04261420A - Epoxy modified aqueous polyurethane resin composition - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention is characterized by solvent resistance, hot water resistance,
The present invention relates to a water-based polyurethane resin composition that has excellent impact resistance and corrosion resistance and is useful as a paint, adhesive, paper processing agent, and surface coating agent.

0002

[Prior Art] Water-based polyurethane resins can be used in paints, adhesives, water-based inks, leather, paper, metals, plastics, wood, etc.
Although it is used as a sealer or top coat for rubber, inorganic materials, etc., it is not necessarily sufficient in terms of resistance to organic solvents, chemicals, water, and salt water. Polyfunctional aziridine or aqueous epoxy may be used as a curing agent to improve performance, but there are problems with pot life and hydrolysis, and both have the disadvantage of being two-component types in terms of stability.

0003

[Problems to be Solved by the Invention] As a result of intensive research to solve the above-mentioned problems, the present invention has been made based on an aqueous polyurethane resin and a polyurethane resin containing two or more epoxy groups per molecule, based on 100 parts by weight of the aqueous polyurethane resin. epoxy compound with 1
An aqueous polyurethane resin composition characterized by containing a product obtained by the reaction in a proportion of ~20 parts by weight (in terms of solid content) has excellent solvent resistance, hot water resistance, impact resistance, and corrosion resistance. This discovery led to the completion of the present invention.

0004

[Means for Solving the Problems] The present invention provides an aqueous polyurethane resin having a carboxyl group, in which 2 epoxy groups are added per molecule to 100 parts by weight of the aqueous polyurethane resin.
The present invention relates to an aqueous polyurethane resin composition characterized by containing a product obtained by reacting an epoxy compound having 1 to 20 parts by weight (in terms of solid content).

[0005] The aqueous polyurethane resin used in the present invention is produced, for example, as follows. A carboxyl group-containing urethane prepolymer having two or more isocyanate groups at the end obtained by reacting the following aliphatic, aromatic, and alicyclic isocyanate compounds with the following carboxyl group-containing polyols and polyols. Use.

[0006] In the above reaction, the ratio of isocyanates to polyols having carboxyl groups and polyols is such that the isocyanate group content of the prepolymer (in terms of solid content) is 0.5% to 10%, preferably 1% to 10%. 4%
Adjust so that Isocyanate group content is 0.
If it is less than 5%, it is difficult to increase the molecular weight sufficiently in the chain extension reaction, and if it is more than 10%, the amount of carbon dioxide gas generated in the chain extension reaction is too large, making it difficult to produce. Further, in the above reaction, the amount of polyols having a carboxyl group is set so that the acid value (in terms of solid content) is 10 or more, preferably 20 or more. If the acid value is less than 10, it will be difficult to self-emulsify, the particle size will become large, and stability will tend to be poor. The above-mentioned carboxyl group-containing urethane prepolymer can be produced by a known method that is exactly the same as that for so-called urethane prepolymers that are commonly used for producing polyurethane resins.

Examples of the above-mentioned isocyanate compounds include 1,4-tetramethylene diisocyanate, 1,
Aliphatic isocyanates such as 6-hexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, 2,8-diisocyanate methyl caproate, 3-isocyanate methyl-3,5,5-trimethylcyclohexyl isocyanate, dicyclohexylmethane Alicyclic diisocyanates such as -4,4'-diisocyanate and methylcyclohexyl-2,4-diisocyanate, toluylene diisocyanate, diphenylmethane diisocyanate, 1,5-naphthene diisocyanate, diphenylmethylmethane diisocyanate,
Tetraalkyldiphenylmethane diisocyanate, 4
, 4'-dibenzyl diisocyanate, aromatic diisocyanates such as 1,3-phenylene diisocyanate,
One type or a mixture of two or more types selected from the group of chlorinated diisocyanates, brominated diisocyanates, and polyisocyanate compounds which are adducts with water are used.

[0008] As for the carboxyl group-containing polyols to be used, any polyol that imparts branched carboxyl groups to the linear prepolymer molecule can be used, but if the carboxyl group content in the prepolymer is increased to do so,
A low molecular weight one having 3 to 10 carbon atoms and having at least one branched carboxyl group is preferable, for example, 2,2
-Dimethylolpropionic acid and the like are preferred. Further, the polyols used in the present invention include known polyols normally used in the production of urethane resins, such as diethylene glycol, butanediol, hexanediol,
Neopentyl glycol, bisphenol A, cyclohexanedimethanol, trimethylolpropane, glycerin, pentaerythritol, polyethylene glycol, polypropylene glycol, polyester polyol, polycaprolactone, polytetramethylene ether glycol, polythioether polyol, polyacetal polyol, polybutadiene polyol, flange methanol Examples include one type or a mixture of two or more types selected from the group such as . These polyols can be appropriately selected depending on the purpose and use, and the necessary physical properties such as hardness and softness can be easily designed.

[0009] Furthermore, as the epoxy compound used in the present invention, the following commercially available epoxy compounds can be used. Examples of epoxy compounds having two epoxy groups in one molecule include Epicote 828 and Epicote 10.
01, Epicote 1002, Epicote 1004, Epicote 1007, Epicote 1009 (Shell Chemical Co., Ltd.), Epolite 400E, Epolite 200E, Epolite 40E, Epolite 80MF (Kyoeisha Yushi Kagaku Kogyo Co., Ltd.), Denacol EX810, 811, 851, 830
, 832, 841, 861, 911, 941, 920,
921, 931, 211, 212, 221, 721, 3
13 (manufactured by Nagase Chemical Industries, Ltd.). In addition, as an epoxy compound having three epoxy groups in one molecule, Denacol E
They are easily available as X314, 321, 421, 512, 521 (Nagase Kasei Kogyo Co., Ltd.), Epicoat 152, 154 (Shell Chemical Co., Ltd.), and the like. Epoxy compounds having four epoxy groups in one molecule are easily available as Denacol EX611, 612, 614, 614B, 622, and the like. Aqueous polyurethane resin containing carboxyl groups in the molecule obtained by the above method 100
The blending ratio of the epoxy compound having two or more epoxy groups in one molecule is preferably 1 to 20 parts by weight (based on solid content) based on the weight part.

The aqueous polyurethane resin used in the present invention is produced by dissolving or suspending a mixture of the carboxyl group-containing urethane prepolymer and the epoxy compound in the following solvent and/or water, and adding a basic organic compound to the mixture. (reacts with carboxyl groups to increase hydrophilicity) and the following extender is added dropwise, or a basic organic compound and extender are dissolved in a solvent and/or water, and a solution of urethane prepolymer is added dropwise. By this method, the carboxyl group-containing urethane prepolymer was made hydrophilic and at the same time reacted with an extender, then diluted with an appropriate amount of water, and under reduced pressure.
A water-based polyurethane resin is obtained by dehydrating and removing solvent until the concentration of non-volatile components reaches 30 to 40%, and further reacting at 70 to 80°C for about 6 hours.

[0011] As the extender used in the present invention, for example, water or diamines are suitable, and as polyamines, for example, ethylenediamine, diethylenetriamine, triethylenetetramine, propylene diamine, butylene diamine, hexamethylene diamine, Cyclohexylene diamine, piperazine, 2-methylpiperazine,
Phenylenediamine, tolylenediamine, xylenediamine, α,α'-methylenebis(2-chloroaniline)
3,3'-dichloro-α,α'-biphenyldiamine,
2,6-diaminopyridine, α,α'-diaminodiphenylmethane, m-xylene diamine, isophorone diamine, N-methyl-3,3'-diaminopropylamine, and adducts of diethylenetriamine and acrylate or their hydrolysis products, etc. can be mentioned. Further, as the basic organic compound for imparting hydrophilicity by reacting with the carboxyl group, any known basic organic compound can be used, but particularly preferred examples include dimethylethanolamine, diethylethanolamine, triethylamine, etc. .

[0012] Also, as a solvent used for resin production,
For example, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, toluene, xylene, isobutyl acetate,
Butyl acetate, acetone, dimethylformamide, N-
Methyl-2-pyrrolidone, diethylene glycol dimethyl ether and the like are suitable. The aqueous polyurethane resin used in the present invention may contain organic solvents, pigments, dyes,
Even if it contains other conventional ingredients such as emulsifiers, surfactants, thickeners, heat stabilizers, leveling agents, antifoaming agents, fillers, antisettling agents, UV absorbers, antioxidants, thinners, etc. good. Furthermore, the aqueous polyurethane resin composition obtained in the present invention can be used to create acrylic emulsions, rubber emulsions,
Alternatively, it can also be blended with other water-based resins. Further, urethane copolymerized with the aqueous urethane resin composition obtained in the present invention and at least one vinyl monomer such as acrylic acid, acrylic ester, methacrylic acid, methacrylic ester, vinyl chloride, styrene, acrylonitrile, vinyl acetate, etc. It goes without saying that it is possible to hybridize the aqueous polyurethane resin composition with the copolymerized copolymer resin and the vinyl monomer described above, and to improve the performance.

[0013]

[Example] Hereinafter, in order to explain the present invention more specifically,
Although the present invention will be described with reference to Examples and Comparative Examples, the present invention is not limited to these Examples. Production of epoxy-modified water-based polyurethane resin

Example 1 In a 2000 ml four-necked flask equipped with a thermometer, a stirrer, and a nitrogen inlet tube, 154% of Q4646B (polyester polyol manufactured by Mitsui Toatsu Chemical Co., Ltd., molecular weight 500) was added.
4g of trimethylolpropane, 1.6g of dimethylolpropionic acid, 34.3g of N-methyl-2-pyrrolidone, 71.7g of ethyl acetate, and 126.1g of isophorone diisocyanate, and heated to 80°C. After reacting for 8 hours, 100 g of ethyl acetate was added for dilution. The NCO group content of the obtained prepolymer was 1
．． It was 8%. To 506.0 g of the above prepolymer,
Epikote 1001 (manufactured by Shell Kagaku Co., Ltd.) at 52.
9g of triethylamine was charged and mixed with 13.3g of triethylamine.
After neutralization with g, the mixture was poured into deionized water to obtain an aqueous resin solution. This aqueous resin solution was subjected to ethyl acetate removal under reduced pressure at 50°C, and then the reaction was carried out for 6 hours while keeping the internal temperature at 70 to 80°C. Final non-volatile content 40.0%, pH 8.6, viscosity 38
A water-based polyurethane resin having a temperature of 0 cp/25°C was obtained.

Example 2 83.7 g of polytetramethylene ether glycol having a molecular weight of 2000, 51.6 g of neopentyl glycol, and 4.2 g of trimethylolpropane were placed in a 2000 ml four-necked flask equipped with a thermometer, a stirrer, and a nitrogen inlet tube. , 21.5 g of dimethylolpropionic acid and 34.3 g of N-methyl-2-pyrrolidone were charged, and 9
The temperature was raised to 0°C to dissolve the contents. Next, it was cooled to 40°C, 86g of acetone was added, and when the internal temperature reached 30°C, 139.0g of tolylene diisocyanate was added dropwise over 1 hour. After the reaction was carried out for 8 hours while keeping the internal temperature at 30 to 40°C, it was diluted with 86 g of acetone. The NCO group content of this prepolymer was 0.90%. 52.9 g of Epicoat 1001 (manufactured by Shell Chemical Co., Ltd.) was added to 506.4 g of the above prepolymer and mixed. 481.5 g of deionized water containing 12.1 g of dimethylethanolamine was kept at 40°C and the above prepolymer 5
A mixture of 06.4 g of 06.4 g and 52.9 g of Epicoat 1001 (manufactured by Shell Chemical Co., Ltd.) was added dropwise, and after deacetonization was performed under reduced pressure at 40°C, the internal temperature was maintained at 70 to 80°C and the reaction was carried out for 6 hours. Nonvolatile content: 40.0%, pH: 8.5,
An aqueous polyurethane resin having a viscosity of 550 cp/25°C was obtained.

Example 3 83.7 g of polycaprolactone with a molecular weight of 2000, 51.6 g of neopentyl glycol, 4.2 g of trimethylolpropane, and dimethylol were placed in a 2000 ml four-necked flask equipped with a thermometer, a stirrer, and a nitrogen inlet tube. 21.5 g of propionic acid, 34.3 g of N-methyl-2-pyrrolidone
g was charged, and the temperature was raised to 90° C. while introducing nitrogen to dissolve the contents. Next, it was cooled to 40°C, 86.0g of acetone was added, and when the internal temperature reached 30°C, 139.0g of tolylene diisocyanate was added dropwise over 1 hour. After keeping the internal temperature at 30 to 40°C and carrying out the reaction for 8 hours,
Diluted with 6.0 g of acetone. This prepolymer N
The CO group content was 0.90%. 52.9 g of Epicoat 1001 (manufactured by Shell Chemical Co., Ltd.) was added to 506.4 g of the above prepolymer and mixed. 481. deionized water containing 12.1 g dimethylethanolamine.
5g was kept at 40°C, and 506.4g of the above prepolymer was added.
and Epicote 1001 (manufactured by Shell Chemical Co., Ltd.) 52.
A water-based polyurethane resin was obtained by dropping a mixture of 9 g and reacting. This water-based polyurethane resin
After further deacetonization under reduced pressure at 40℃, the internal temperature was lowered to 70℃.
The reaction was carried out at ~80°C for 6 hours, and the non-volatile content was finally reduced to 3.
An aqueous polyurethane resin having a pH of 9.5%, a pH of 8.5, and a viscosity of 650 cp/25° C. was obtained.

Example 4 Into a 2,000 ml four-necked flask equipped with a thermometer, stirrer, and nitrogen inlet tube, 83.7 g of polytetramethylene ether glycol having a molecular weight of 2,000, 51.6 g of neopentyl glycol, and 4.0 g of trimethylolpropane were added. 2g, dimethylolpropionic acid 21.5g, N-methyl-2-
34.4 g of pyrrolidone was charged, and the temperature was raised to 90° C. while introducing nitrogen to dissolve the contents. Next, it was cooled to 40°C, 86g of acetone was added, and when the internal temperature reached 30°C, 139.0g of tolylene diisocyanate was added dropwise over 1 hour. After the reaction was carried out for 8 hours while keeping the internal temperature at 30 to 40°C, it was diluted with 86 g of acetone. The NCO group content of the obtained prepolymer was 0.90%. Epicoat 100 was added to 506.4 g of the above prepolymer.
4 (manufactured by Shell Chemical Co., Ltd.) was added dropwise and reacted to obtain an aqueous polyurethane resin. This aqueous polyurethane resin was further deacetonized under reduced pressure, and then reacted for 6 hours while keeping the internal temperature at 70 to 80°C, resulting in a final nonvolatile content of 38.0%, pH of 8.8, and viscosity of 68.
A water-based polyurethane resin having a temperature of 0 cp/25°C was obtained.

Comparative Example 1 83.7 g of polytetramethylene ether glycol with a molecular weight of 2000, 51.6 g of neopentyl glycol, and 4.2 g of trimethylolpropane were placed in a 2000 ml four-necked flask equipped with a thermometer, stirrer, and nitrogen inlet tube. , 21.5 g of dimethylolpropionic acid, and 34.4 g of N-methyl-2-pyrrolidone were charged, and the mixture was heated at 90° C. while introducing nitrogen.
The temperature was raised to ℃ to dissolve the contents. Next, it was cooled to 40°C, 86.0g of acetone was added, and when the internal temperature reached 30°C, 139.0g of tolylene diisocyanate was added dropwise over 1 hour. After reaction was carried out for 8 hours while keeping the internal temperature at 30 to 40°C, it was diluted with 86.0 g of acetone. The NCO group content of this prepolymer was 0.90%. 481.5 g of deionized water containing 12.1 g of dimethylethanolamine was kept at 40° C., and 506.4 g of the above prepolymer was added dropwise to react to obtain an aqueous polyurethane resin. Add this water-based polyurethane resin to 4 more times.
Deacetonization was performed under reduced pressure at 0°C, and the nonvolatile content was finally reduced to 38.
An aqueous polyurethane resin having a pH of 7.6 and a viscosity of 400 cp/25° C. was obtained.

Comparative Example 2 In a 2,000 ml four-necked flask equipped with a thermometer, stirrer, and nitrogen inlet tube, 154 mL of Q4646B (polyester polyol manufactured by Mitsui Toatsu Chemical Co., Ltd., molecular weight 500) was added.
4g of trimethylolpropane, 1.6g of dimethylolpropionic acid, 34.3g of N-methyl-2-pyrrolidone, 71.7g of ethyl acetate, and 126.1g of isophorone diisocyanate were charged at 80°C. After reacting for 8 hours, 100 g of ethyl acetate was added for dilution. The NCO group content of the obtained prepolymer was 1
．． It was 8%. To 506.0 g of the above prepolymer,
After neutralization with 13.3 g of triethylamine, the mixture was poured into deionized water at 50° C. to obtain an aqueous resin solution. This aqueous resin solution was decompressed with ethyl acetate at 50°C, and the nonvolatile content was 37.5%.
%, pH 7.8, and viscosity 50 cp/25°C. Water was added to the aqueous polyurethane resin compositions containing the epoxy compounds of Examples 1 to 4 and the aqueous polyurethane resin compositions of Comparative Examples 1 and 2 to reduce the nonvolatile content by 3.
5%, glass plate and polished mild steel plate (JIS, G.3
141) was coated with a bar coater to a thickness of 10 microns after drying. The coating film was dried for 7 days in a constant temperature and humidity chamber at a temperature of 20° C. and a humidity of 60%, and then subjected to a performance test. The test method is JI
It was carried out according to SK5400.

[0020]

[Table 1] Test method and evaluation criteria DuPont impact: Center of impact 1/2 inch, load 1000g, backing Solvent resistance: Soak gauze in solvent and coat the coating surface with
Rub 0 times and observe the surface condition ×; Paint film dissolves after 50 times or less, △; Loss of gloss, ◎; Retains almost the state before the test Hot water resistance: Immerse in boiling water for 4 hours and observe the whitening condition × ×: Whitening (no transparency at all), ◎: No whitening

0
021]

[Table 2] Test method and evaluation criteria Salt spray test: According to JIS K5400 ××; Rust, blisters, paint film whitening on the entire surface ×; Rust entering from the cut part, whitening ○; Partial whitening ◎; No change

[0022]

Effects of the Invention It is clear from Tables 1 and 2 that the aqueous polyurethane resin composition obtained in the present invention has excellent solvent resistance, hot water resistance, salt spray resistance, and moisture resistance.

Claims (5)

[Claims] Claim 1: An aqueous polyurethane resin having a carboxyl group in the molecule, and 1 to 20 parts by weight (in terms of solid content) of an epoxy compound having two or more epoxy groups in one molecule, per 100 parts by weight of the aqueous polyurethane resin. ) A water-based polyurethane resin composition characterized by containing a product obtained by reacting at a ratio of: 2. A water-based polyurethane resin is first reacted with an isocyanate compound, a polyol, and a polyol having a carboxyl group to form a terminal resin having an isocyanate group content (in terms of solid content) of 0.5% to 10%. An epoxy compound having two or more epoxy groups in one molecule is mixed with a carboxyl group-containing urethane prepolymer having two or more isocyanate groups, and then deionized water is mixed with a basic organic compound and an extender. By charging the prepolymer into the urethane prepolymer, the carboxyl group-containing urethane prepolymer is made hydrophilic, and at the same time, by reacting with the extender, the concentration of nonvolatile matter obtained is 30 to 4.
The aqueous polyurethane resin composition according to claim 1, wherein the aqueous polyurethane resin composition contains 0%. 3. The aqueous polyurethane resin composition according to claim 2, wherein the carboxyl group-containing polyol has at least one branched carboxyl group and has a low molecular weight of 3 to 10 carbon atoms. 4. The aqueous polyurethane resin composition according to claim 2, wherein the basic organic compound is dimethylethanolamine, diethylethanolamine, or triethylamine. 5. The aqueous polyurethane resin composition according to claim 2, wherein the extender is water or polyamines.