A water-based metal cleaning agent

Abstract

The present invention provides a water-based metal cleaning agent, belonging to the field of metal cleaning agents. The water-based metal cleaning agent comprises the following components, in parts by weight: 10-25 parts of a highly branched fatty alcohol-capped polyether, 2-5 parts of an alkyl diphenyl ether sulfonate, 5-10 parts of a builder, and 0.5-1 part of a chelating agent, with water making up the total weight to 100 parts. The present invention prepares a highly branched fatty alcohol-capped polyether with cleaning, high alkali resistance, and rust prevention functions. Using this polyether as the main component, a water-based metal cleaning agent is prepared, exhibiting low foaming, high alkali resistance, and rust prevention properties.

Description

Technical Field

[0001] The invention belongs to the field of metal cleaning agents, and in particular relates to a water-based metal cleaning agent. Background Art

[0002] When painting, electroplating, assembling metal surfaces, and during production, it is necessary to clean the surfaces of the processing components and the machines used in production. Failure to do so effectively will damage the quality of the product and affect the quality and service life of the product and processing machinery.

[0003] Currently, commonly used metal cleaners are divided into solvent-based, semi-solvent-based, and water-based types. Among solvent-based metal cleaners, petroleum solvents are flammable, explosive, and wasteful of resources. Chlorofluorocarbons are the most commonly used solvent-based metal cleaners, but they have been banned due to their damage to the atmospheric ozone layer. As a result, solvent-based metal cleaners are gradually being replaced by semi-solvent-based and water-based metal cleaners. Compared with semi-solvent-based metal cleaners, water-based metal cleaners have more prominent application advantages. However, water-based metal cleaners also generally have the following shortcomings in industrial high-pressure cleaning: 1) Excessive foaming, which is not conducive to cleaning; 2) The compatibility and stability of the various components under strong alkaline conditions are poor, resulting in limited cleaning ability. The existing technology lacks low-foaming, high-alkalinity-resistant, and rust-proof water-based metal cleaners. Summary of the Invention

[0004] The purpose of the present invention is to provide a water-based metal cleaning agent with low foaming, high alkali resistance and excellent rust prevention performance.

[0005] The purpose of the present invention is achieved by adopting the following technical solutions:

[0006] A water-based metal cleaning agent, comprising the following components in parts by weight:

[0007]

[0008] In the present invention, the highly branched fatty alcohol-terminated polyether has the following structural formula:

[0009]

[0010] Wherein, 0≤m≤20, 0≤n≤20 and m and n are integers, R1 is a linear or branched alkyl group having 6 to 22 carbon atoms, and R2 is a methyl group or a butyl group.

[0011] In the present invention, the preparation method of the highly branched fatty alcohol-terminated polyether comprises the following steps:

[0012] (1) Fatty alcohol and epoxide react in the presence of a catalyst at a temperature of 90 to 120° C. for 3 to 8 hours and a reaction pressure of 0.2 to 0.4 MPa to obtain a fatty alcohol polyether having the following general formula:

[0013]

[0014] Wherein: 0≤m≤20, 0≤n≤20 and m and n are integers, R1 is a linear or branched alkyl group of 6 to 22 carbon atoms;

[0015] (2) Fatty alcohol polyether is first reacted with a base at 30-80°C for 1-4 hours, a phase transfer catalyst is added, and then 1,3-dichloropropanol is added and reacted at 50-100°C for 4-10 hours. After the reaction is completed, vacuum is applied at 100-120°C for 0.5-2 hours to remove 1,3-dichloropropanol to obtain a double-terminal fatty alcohol polyether with the following structural formula:

[0016]

[0017] Wherein: 0≤m≤20, 0≤n≤20 and m and n are integers, R1 is a linear or branched alkyl group of 6 to 22 carbon atoms;

[0018] (3) The double-terminated fatty alcohol polyether is reacted with a base at 50-100°C for 1-4 hours, and then an alkyl end-capping agent is added and reacted at 50-120°C for 4-10 hours to obtain a highly branched fatty alcohol end-capped polyether having the following structural formula:

[0019]

[0020] Wherein, 0≤m≤20, 0≤n≤20 and m and n are integers, R1 is a linear or branched alkyl group having 6 to 22 carbon atoms, and R2 is a methyl group or a butyl group.

[0021] In the present invention, the builder is prepared by mixing sodium lauryl sulfate, triethanolamine and borax in a mass ratio of 2:1:1.

[0022] In the present invention, the chelating agent is one of sodium pyrophosphate, sodium tripolyphosphate or sodium hexapolyphosphate or a combination thereof; the alkyl diphenyl ether sulfonate is one of sodium dodecyl diphenyl ether disulfonate and sodium hexadecyl diphenyl ether disulfonate or a combination thereof.

[0023] In the present invention, R1 in the highly branched fatty alcohol-terminated polyether is one or two of n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, n-nonadecyl, n-eicosyl, n-heneicosyl, n-docosyl, isohexyl, isoheptyl, isooctyl, isononyl, isodecyl, isoundecyl, isododecyl, isotridecyl, isotetradecyl, isopentadecyl, isohexadecyl, isoheptadecyl, isooctadecyl, isononadecyl, isoeicosyl, isohexadecyl, isodocosyl, 2-ethylhexyl, 2-propylheptyl, or a mixture of two or more thereof.

[0024] In the present invention, after the reaction in step (3) of the method for preparing highly branched fatty alcohol-capped polyether is completed, phosphoric acid is added for neutralization, a refining agent is added for adsorption, and the mixture is filtered after vacuum distillation to obtain highly branched fatty alcohol-capped polyether.

[0025] In the present invention, the epoxide in step (1) is ethylene oxide or propylene oxide, and the molar ratio of epoxide to fatty alcohol is 1-20:1; the catalyst is potassium hydroxide or potassium methoxide, and the amount used is 0.05-0.5% of the total mass of the fatty alcohol and the epoxide.

[0026] In the present invention, the base in step (2) is sodium hydroxide, potassium hydroxide or sodium methoxide, the molar ratio of the base to the fatty alcohol polyether is 1 to 4:1, and the molar ratio of 1,3-dichloropropanol to the fatty alcohol polyether is 0.5 to 1:1; the phase transfer catalyst is one or a mixture of benzyltriethylammonium chloride (TEBA), tetrabutylammonium bromide, tetrabutylammonium chloride, and tetrabutylammonium hydrogen sulfate (TBAB), and the amount used is 0.1 to 0.3% of the mass of the fatty alcohol polyether.

[0027] In the present invention, the base in step (3) is sodium hydroxide, potassium hydroxide or sodium methoxide, and the molar ratio of the base to the double-ended fatty alcohol polyether is 1 to 4:1; the alkyl end-capping agent is methyl chloride, butyl chloride or butyl bromide, and the molar ratio of the end-capping agent to the double-ended fatty alcohol polyether is 1 to 4:1; the refining agent is magnesium silicate, and the amount of the refining agent is 0.3% to 1% of the mass of the highly branched fatty alcohol end-capped polyether.

[0028] Beneficial Effects: The present invention prepares a highly branched fatty alcohol-terminated polyether with cleaning, high alkali resistance, and rust prevention functions. A water-based metal cleaning agent prepared using the polyether as the main component exhibits low foaming, high alkali resistance, and rust prevention properties. Because the highly branched fatty alcohol-terminated polyether in the present invention has excellent low foaming, emulsifying, and penetrating abilities, it synergistically acts with a chelating agent to easily adhere to metal surfaces, isolating moisture and preventing secondary rust. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is the hydrogen nuclear magnetic resonance spectrum of the highly branched fatty alcohol-terminated polyether prepared in Example 1. The abscissa is the chemical shift, and the unit is ppm. DETAILED DESCRIPTION

[0030] The present invention is further described in detail below through examples, but the scope of protection claimed in the present invention is not limited to the scope shown in the examples.

[0031] Example 1

[0032] 1. Preparation of fatty alcohol polyether

[0033] Preparation of fatty alcohol polyether, comprising the following steps:

[0034] (1) 288g of isononanol (2mol) and 1.1g of potassium methoxide were added to a reactor, replaced with nitrogen three times, and then 440g of ethylene oxide (10mol) was introduced. During the introduction of ethylene oxide, the temperature in the reactor was maintained at 100°C and the pressure was 0.3MPa. The feeding time of ethylene oxide was 5h. After the feeding was completed, the reactor was aged for 3h at 110°C and a pressure of 0.3MPa. After the aging reaction was completed, vacuum was applied to remove unreacted ethylene oxide to obtain 723g of fatty alcohol polyether, whose structural formula is The hydroxyl value of the fatty alcohol polyether was determined by the phthalic anhydride-pyridine method (GB / T 12008.3-2009) to be 155.21 mg KOH / g, the number average molecular weight was 361, and the yield was 99.31%.

[0035] (2) Add 120g NaOH (3mol) to 723g fatty alcohol polyether (2mol) obtained in step (1), and react at a vacuum degree of 0.95MPa and 60°C for 3h; then add 1.45g tetrabutylammonium bromide, raise the temperature to 80°C, and slowly introduce 155g 1,3-dichloropropanol (1.2mol) at 80°C and 0.3MPa for 2h. After the introduction is completed, continue to react at 80°C and 0.3MPa (supplement with nitrogen when the pressure is insufficient) for 8h. After the reaction is completed, vacuum is applied at 110°C for 1h to remove unreacted 1,3-dichloropropanol, to obtain 765g double-end fatty alcohol polyether, whose structural formula is

[0036]

[0037] The hydroxyl value of the double-terminated fatty alcohol polyether was determined to be 73.83 mgKOH / g by a phthalic anhydride-pyridine method (GB / T 12008.3-2009), and the end-capping rate was 97.92%.

[0038] (3) Add 48 g of NaOH (1.2 mol) to 765 g of double-ended fatty alcohol polyether (0.98 mol), and react at a vacuum degree of 0.95 MPa and 90°C for 3 h; cool to 50°C, and slowly introduce 80 g of chloromethane (1.6 mol) at 50°C and 0.3 MPa over 2 h. After the introduction is completed, heat to 100°C and continue to react at 100°C and 0.3 MPa (nitrogen is used to supplement the pressure when insufficient) for 8 h. After the reaction, unreacted chloromethane was removed by vacuum at 110° C. to obtain 775 g of crude highly branched fatty alcohol-terminated polyether, and then 40 g of distilled water and 8 g of phosphoric acid were added to 775 g of crude highly branched fatty alcohol-terminated polyether to neutralize it to neutrality. 3 g of magnesium silicate was added and stirred for 1 h. The water was removed by reduced pressure distillation at 100° C. and a vacuum degree of 0.098 MPa for 3 h. The residue was filtered to obtain a highly branched fatty alcohol-terminated polyether, which was subjected to hydrogen nuclear magnetic resonance spectroscopy analysis (such as Figure 1 shown), 1 H NMR data: (CDCl3 as solvent, TMS as internal standard): 3.76-3.37 (m, 40H, -OCH2-), 1.58-1.42 (s, 8H, -CH2-), 1.40-1.37 (s, 3H, -CH-), 1.24-1.20 (d, 4H, -CH2-O), 1.07-1.03 (t, 3H, -OCH3), 0.91-0.924 (t, 24H, -CH3). The structural formula of the highly branched fatty alcohol-terminated polyether was determined to be

[0039] The hydroxyl value of the highly branched fatty alcohol-capped polyether was determined by a phthalic anhydride-pyridine method (GB / T 12008.3-2009) to be 0.76 mg KOH / g, and the capping rate was 98.97%.

[0040] 2. Preparation of water-based metal cleaning agent

[0041] Water-based metal cleaning agent B-1 is composed of the following components, by weight: 20 parts of highly branched fatty alcohol-terminated polyether, 3 parts of sodium lauryl diphenyl ether disulfonic acid salt, 8 parts of a builder, and 0.8 parts of sodium tripolyphosphate. The mixture is made up to 100 parts with water, mixed, and stirred evenly to obtain water-based metal cleaning agent B-1. The builder is a mixture of sodium lauryl sulfate, triethanolamine, and borax in a mass ratio of 2:1:1.

[0042] Comparative Example 1

[0043] 1. Preparation of fatty alcohol methyl terminated polyether

[0044] Preparation of fatty alcohol methyl terminated polyether comprises the following steps:

[0045] (1) Preparation formula The specific method is the same as step (1) in title 1 of Example 1;

[0046] (2) Add 120 g of NaOH (3 mol) to 723 g of fatty alcohol polyether (2 mol) obtained in step (1), and react at a vacuum degree of 0.95 MPa and 60° C. for 3 h; cool to 50° C., and slowly introduce 120 g of methyl chloride (2.4 mol) at 50° C. and 0.3 MPa for 2 h. After the introduction is complete, heat to 80° C., and continue to react at 80° C. and 0.3 MPa (nitrogen is added when the pressure is insufficient) for 8 h. After the reaction is completed, vacuum remove unreacted methyl chloride at 110° C. to obtain 768 g of crude fatty alcohol methyl-terminated polyether. Then, add 20 g of distilled water and 4 g of phosphoric acid to the crude fatty alcohol methyl-terminated polyether to neutralize it to neutrality, add 2 g of magnesium silicate, stir for 1 h, and then remove moisture by reduced pressure distillation at 100° C. (vacuum degree of 0.098 MPa) for 3 h, and filter to remove the filter residue to obtain fatty alcohol methyl-terminated polyether. Its structural formula is The hydroxyl value of the fatty alcohol methyl terminated polyether was determined by a phthalic anhydride-pyridine method (GB / T 12008.3-2009) to be 1.03 mg KOH / g, and the termination rate was 99.33%.

[0047] 2. Method of water-based metal cleaning agent B-2

[0048] Water-based metal cleaner B-2 is composed of the following components, by weight: 20 parts fatty alcohol methyl-terminated polyether, 3 parts sodium dodecyl diphenyl ether disulfonic acid salt, 8 parts builder, and 0.8 parts sodium tripolyphosphate. The mixture is made up to 100 parts with water, mixed, and stirred evenly to obtain water-based metal cleaner B-2. The builder is a mixture of sodium lauryl sulfate, triethanolamine, and borax in a mass ratio of 2:1:1.

[0049] Comparative Example 3

[0050] 1. Preparation of fatty alcohol polyoxyethylene ether

[0051] 200g of C12-14 alcohol (mass ratio of C12 alcohol to C14 alcohol = 7 / 3, 1 mol, purchased from Corning) and 1.1g of potassium methoxide were added to a reactor, nitrogen was replaced three times, and then 440g of ethylene oxide (9 mol) was introduced. During the introduction of ethylene oxide, the temperature in the reactor was maintained at 100°C and the pressure was 0.3MPa. The feeding time of ethylene oxide was 5h. After the feeding was completed, the reactor was aged for 3h at 110°C and a pressure of 0.3MPa. After the aging reaction was completed, vacuum was applied to remove unreacted ethylene oxide to obtain 657g of fatty alcohol polyoxyethylene ether (AEO-9), whose structural formula is R is C12-14. The hydroxyl value of AEO-9 was determined to be 85.93 mg KOH / g by the phthalic anhydride-pyridine method (GB / T12008.3-2009), the average molecular weight was 653, and the yield was 99.54%.

[0052] 2. Method of water-based metal cleaning agent B-3

[0053] Water-based metal cleaner B-3 is composed of the following components, by weight: 20 parts AEO-9, 3 parts sodium dodecyl diphenyl ether disulfonate, 8 parts builder, and 0.8 parts sodium tripolyphosphate. The mixture is made up to 100 parts with water and stirred thoroughly to obtain water-based metal cleaner B-3. The builder is a mixture of sodium lauryl sulfate, triethanolamine, and borax in a mass ratio of 2:1:1.

[0054] Example 2 Performance Test of Water-Based Metal Cleaner

[0055] The following performance tests were conducted on water-based metal cleaning agents B-1, B-2, and B-3.

[0056] 1. Foam performance test: Take 30 ml of water-based metal cleaning agent and add it to a 100 ml stoppered graduated cylinder. Place it in a 30°C oven for 30 minutes, then take it out and shake it up and down for 10 minutes. The shaking distance is about 0.33 m and the shaking frequency is 100 times / min. After shaking, open the stopper of the graduated cylinder and place it in a 30°C oven. Let it stand for 10 minutes and record the residual foam height.

[0057] 2. Cleaning ability test

[0058] Oiling the test piece: Weigh the mass of the test piece, recorded as m1. Heat crude oil to 80°C and immerse the test piece (45# steel, 50mm x 50mm x 5mm) in it. After 5 minutes, remove the test piece vertically and hang it on a test piece rack for 20 minutes. Scrape off any oil droplets accumulated on the bottom of the test piece, then place it outdoors in a natural environment. After two days, obtain the oiled test piece. Weigh the mass of the oiled test piece, recorded as m2. The amount of oil on the test piece is m2 - m1.

[0059] Cleaning Ability Test: Dilute each of the water-based cleaning agents B-1, B-2, and B-3 10-fold with water. Take 500ml of each diluted solution, place it in a stoppered container, and place it in a 30°C oven for 1 hour. Then pour it into an oscillating washing tank. Take three oiled test pieces and fix them on an oscillating washing tank, keeping the surface perpendicular to the oscillation direction. Immerse the three oiled test pieces in the oscillating washing tanks containing B-1, B-2, and B-3 for 3 minutes. Then, remove the test pieces and oscillate them in 500ml of 30°C distilled water for 3 minutes. Remove the test pieces and place them in a 70°C oven to dry and weigh them. The weight is recorded as m3, where m2 - m3 is the amount of oil removed. The degreasing ability of the cleaning agent is represented by p, which is (m2 - m3) / (m2 - m1) * 100%. Each sample is tested three times, and the average value is taken.

[0060] 3. Anti-rust and corrosion performance test: The anti-rust and corrosion performance test was carried out in accordance with "JB / T4323.1-1999 Water-based Metal Cleaner", and the test sample was 45# steel.

[0061] 4. Alkali resistance test: 3 parts by volume of a water-based metal cleaner was mixed with 97 parts by volume of NaOH aqueous solutions of different concentrations. The highest NaOH aqueous solution concentration at which the solution became clear was taken as the alkali resistance.

[0062] Table 1 Performance test results

[0063] project B-1 B-2 B-3 Foam height / mm 2 5 8 Cleaning capacity / % 99 96 95 Anti-rust performance test qualified Slight rust spots Rust spots Corrosion performance test No corrosion, no discoloration Weight loss: 1.8 mg Weight loss: 2.6 mg Alkali resistance g / L 140 60 40

[0064] As can be seen from Table 1, the water-based metal cleaner B-1 has low foaming properties and excellent cleaning ability, and can effectively inhibit corrosion and rust on metal surfaces. At the same time, its alkali resistance is greatly improved compared to the conventional fatty alcohol polyoxyethylene ether (AEO-9) formula.

Claims

1. A water-based metal cleaning agent, comprising the following components in parts by weight: 10-25 parts of highly branched fatty alcohol-terminated polyether 2-5 parts of alkyl diphenyl ether sulfonate 5-10 parts detergent 0.5-1 part of chelating agent Make up to 100 parts with water; The highly branched fatty alcohol-terminated polyether has the following structural formula: , Wherein, 0≤m≤20, 0≤n≤20 and m and n are integers, R1 is a linear or branched alkyl group with 6 to 22 carbon atoms, and R2 is a methyl group or a butyl group; the builder is a mixture of sodium lauryl sulfate, triethanolamine and borax in a mass ratio of 2:1:1; the chelating agent is one of sodium pyrophosphate, sodium tripolyphosphate or sodium hexapolyphosphate, or a combination thereof.

2. The water-based metal cleaning agent according to claim 1, characterized in that The preparation method of the highly branched fatty alcohol-terminated polyether comprises the following steps: (1) Fatty alcohol and epoxide react in the presence of a catalyst at a temperature of 90-120°C for 3-8 hours and a reaction pressure of 0.2-0.4 MPa to obtain fatty alcohol polyether having the following general formula: , Wherein: 0≤m≤20, 0≤n≤20 and m and n are integers, R1 is a linear or branched alkyl group of 6 to 22 carbon atoms; (2) Fatty alcohol polyether is first reacted with alkali at 30-80°C for 1-4 hours, a phase transfer catalyst is added, and then 1,3-dichloropropanol is added and reacted at 50-100°C for 4-10 hours. After the reaction is completed, vacuum is applied at 100-120°C for 0.5-2 hours to remove 1,3-dichloropropanol to obtain a double-terminal fatty alcohol polyether with the following structural formula: , Wherein: 0≤m≤20, 0≤n≤20 and m and n are integers, R1 is a linear or branched alkyl group of 6 to 22 carbon atoms; (3) The double-terminated fatty alcohol polyether is reacted with a base at 50-100°C for 1-4 hours, and then an alkyl end-capping agent is added and reacted at 50-120°C for 4-10 hours to obtain a highly branched fatty alcohol end-capped polyether with the following structural formula: ， Wherein, 0≤m≤20, 0≤n≤20 and m and n are integers, R1 is a linear or branched alkyl group having 6 to 22 carbon atoms, and R2 is a methyl group or a butyl group.

3. The water-based metal cleaning agent according to claim 2, characterized in that The alkyl diphenyl ether sulfonate is one of dodecyl diphenyl ether disulfonic acid sodium salt, hexadecyl diphenyl ether disulfonic acid sodium salt or a combination thereof.

4. The water-based metal cleaning agent according to claim 3, characterized in that In the highly branched fatty alcohol-terminated polyether, R1 is one or two of n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, n-nonadecyl, n-eicosyl, n-heneicosyl, n-docosyl, isohexyl, isoheptyl, isooctyl, isononyl, isodecyl, isoundecyl, isododecyl, isotridecyl, isotetradecyl, isopentadecyl, isohexadecyl, isoheptadecyl, isooctadecyl, isononadecyl, isoeicosyl, isohexadecyl, isodocosyl, 2-ethylhexyl, and 2-propylheptyl, and a mixture of two or more thereof.

5. The water-based metal cleaning agent according to claim 4, characterized in that After the reaction of step (3) of the method for preparing highly branched fatty alcohol-capped polyether is completed, phosphoric acid is added for neutralization, a refining agent is added for adsorption, and the mixture is filtered after vacuum distillation to obtain the highly branched fatty alcohol-capped polyether.

6. The water-based metal cleaning agent according to claim 5, characterized in that In step (1), the epoxide is ethylene oxide or propylene oxide, and the molar ratio of epoxide to fatty alcohol is 1 to 20:1; the catalyst is potassium hydroxide or potassium methoxide, and the amount used is 0.05 to 0.5% of the total mass of the fatty alcohol and the epoxide.

7. The water-based metal cleaning agent according to claim 6, characterized in that The alkali in step (2) is sodium hydroxide, potassium hydroxide or sodium methoxide, the molar ratio of the alkali to the fatty alcohol polyether is 1 to 4:1, and the molar ratio of 1,3-dichloropropanol to the fatty alcohol polyether is 0.5 to 1:1; the phase transfer catalyst is one or a mixture of benzyltriethylammonium chloride (TEBA), tetrabutylammonium bromide, tetrabutylammonium chloride, and tetrabutylammonium hydrogen sulfate (TBAB), and the amount used is 0.1 to 0.3% of the mass of the fatty alcohol polyether.

8. The water-based metal cleaning agent according to claim 7, characterized in that In step (3), the base is sodium hydroxide, potassium hydroxide or sodium methoxide, and the molar ratio of the base to the double-ended fatty alcohol polyether is 1 to 4:1; the alkyl end-capping agent is methyl chloride, butyl chloride or butyl bromide, and the molar ratio of the end-capping agent to the double-ended fatty alcohol polyether is 1 to 4:1; the refining agent is magnesium silicate, and the amount of the refining agent is 0.3% to 1% of the mass of the highly branched fatty alcohol end-capped polyether.

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