Barium-free environmentally friendly electrostatic spray rust-preventive oil

Abstract

The barium-free environmentally friendly electrostatic spray rust-preventive oil of this invention is composed of the following raw material components by mass percentage: 10%-20% composite barium-free rust inhibitor, 1%-3% oiliness agent, 0.5%-1.0% alcohol ether carboxylic acid surfactant, 0.2%-0.5% antioxidant, 0.03%-0.1% copper corrosion inhibitor, and the balance being biodegradable base oil. This barium-free environmentally friendly electrostatic spray rust-preventive oil does not contain the heavy metal barium, and the base oil is a biodegradable synthetic ester base oil with a biodegradability rate greater than 60%, possessing substantial environmental protection characteristics. It has good rust prevention and lubrication properties, high breakdown voltage, good low-temperature fluidity, suitable viscosity, easy atomization, and easy cleaning. It will not form dirt on the metal surface or cause metal discoloration, and is suitable for electrostatic spray rust prevention treatment of metal sheet and strip materials.

Description

Technical Field

[0001] This invention belongs to the field of rust-preventive oil technology, and relates to a barium-free environmentally friendly electrostatic spraying rust-preventive oil. Background Technology

[0002] Traditional rust prevention treatment for metal sheets typically involves applying rust-preventive oil using a roller coater, which suffers from problems such as missed areas, uneven coating, and increased production costs. Electrostatic coating technology has since been developed, offering advantages such as high-quality coating, uniform application, significant oil savings, and improved working conditions. However, ordinary rust-preventive oils cannot be used in electrostatic spraying machines; electrostatic spraying rust-preventive oil must be used instead.

[0003] Currently available electrostatic spray rust-preventive oils are mainly barium-containing products. Although some barium-free products exist, their rust-preventive period is short or their rust-preventive data is lacking, insufficient to support their performance characteristics. The base oils used are still non-degradable mineral-based base oils, which do not actually possess strict environmental protection characteristics. Since rust-preventive oils are open-ended consumable lubricants that cannot be recycled and ultimately enter the environment, their environmental characteristics are particularly important. The surfactants used are mostly alkylphenol polyoxyethylene ethers or fatty alcohol polyoxyethylene ethers, with generally poor atomization effects and poor degreasing properties, which can easily cause discoloration of the rust-preventive oil film and even lead to dirt or discoloration on the surface of metal materials. Summary of the Invention

[0004] The purpose of this invention is to provide a barium-free, environmentally friendly electrostatic spray rust-preventive oil with good atomization performance and washability.

[0005] The technical solution adopted in this invention is a barium-free environmentally friendly electrostatic spray rust-preventive oil, which is composed of the following components by mass percentage: 10%-20% composite barium-free rust inhibitor, 1%-3% oiliness agent, 0.5%-1.0% alcohol ether carboxylic acid surfactant, 0.2%-0.5% antioxidant, 0.03%-0.1% copper corrosion inhibitor, and the balance being biodegradable base oil.

[0006] The present invention is further characterized in that: the composite barium-free rust inhibitor is composed of the following components by mass percentage: 20%-30% calcium petroleum sulfonate, 30%-45% dinonylnaphthalene sulfonate calcium, 10%-25% dodecenyl succinic acid, 5%-15% oxidized wax ester, and 5%-10% imidazoline amide type corrosion inhibitor, the sum of the mass percentages of the above components being 100%;

[0007] The general structural formula of imidazoline amide type corrosion inhibitors is:

[0008]

[0009] Where R is a straight-chain or branched hydrocarbon group of C10 to C21, and n is an integer from 0 to 2;

[0010] The general structural formula of alcohol ether carboxylic acid surfactants is:

[0011]

[0012] Where R' is a straight-chain or branched hydrocarbon group of C8 to C22, and m is an integer of 5 to 12;

[0013] The oiling agent is any one or a combination of several of the following: polylactone castor oil, polylactone 12-hydroxystearate, dimer ester, trimer ester, and pentaerythritol ester of lanolin fatty acid.

[0014] The antioxidant is any one or a combination of several of the following: 2,6-di-tert-butyl-p-cresol, 2,6-di-tert-butyl-p-(dimethylaminomethyl)phenol, 4,4'-methylene-bis-2,6-di-tert-butylphenol, and pentaerythritol tetrakis(β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid);

[0015] The copper corrosion inhibitor is any one or a combination of several of benzotriazole, methylbenzotriazole, benzotriazole Mannich condensate, methylbenzotriazole Mannich condensate, and thiadiazole derivatives;

[0016] Biodegradable base oil has a kinematic viscosity of 10 mmHg at 40°C. 2 / s-32mm 2 Synthetic ester base oils with a biodegradability rate greater than 60% per second.

[0017] The beneficial effects of this invention are:

[0018] (1) The barium-free environmentally friendly electrostatic spraying rust-preventive oil of the present invention does not contain heavy metal barium (barium content is less than 10ppm), and the base oil is selected from biodegradable synthetic ester base oil with a biodegradation rate of more than 60%, which has substantial environmental protection characteristics.

[0019] (2) The barium-free environmentally friendly electrostatic spraying rust-preventive oil of the present invention has good rust prevention and lubrication performance, high breakdown voltage, good low temperature fluidity, suitable viscosity, easy atomization, easy cleaning, and will not form dirt on the metal surface or cause metal discoloration. It is suitable for electrostatic spraying rust prevention treatment of metal plate and strip materials. Detailed Implementation

[0020] The present invention will now be described in detail with reference to specific embodiments.

[0021] The barium-free, environmentally friendly electrostatic spraying rust-preventive oil of the present invention is composed of the following raw material components by weight percentage:

[0022] The compound barium-free rust inhibitor consists of 10%-20%, oiliness agent 1%-3%, alcohol ether carboxylic acid surfactant 0.5%-1.0%, antioxidant 0.2%-0.5%, copper corrosion inhibitor 0.03%-0.1%, and the balance is biodegradable base oil.

[0023] Furthermore, the barium-free environmentally friendly electrostatic spraying rust-preventive oil of the present invention comprises a composite barium-free rust inhibitor including calcium petroleum sulfonate, calcium dinonylnaphthalene sulfonate, dodecenyl succinic acid, oxidized wax ester, and an imidazoline amide type corrosion inhibitor as shown in formula (1):

[0024]

[0025] In the general structural formula (1), R is a straight-chain or branched hydrocarbon group of C10 to C21, and n is an integer from 0 to 2. This type of imidazoline amide corrosion inhibitor contains a unique imidazoline five-membered ring, in which the nitrogen atom can form a coordinate bond with the empty d orbitals on the metal surface, thereby forming a strong monomolecular adsorption film on the metal surface; its unique imidazoline five-membered ring can also change the charge distribution and the redox potential of hydrogen ions on the metal surface; and the nonpolar alkyl chain R forms a hydrophobic layer, preventing the corrosive medium from entering the metal surface. Therefore, the imidazoline amide corrosion inhibitor shown in formula (1) has excellent corrosion inhibition effect on ferrous metals.

[0026] The total mass of the composite barium-free rust inhibitor is 100%. The composite barium-free rust inhibitor contains 20%-30% calcium petroleum sulfonate, 30%-45% dinonylnaphthalene sulfonate, 10%-25% dodecenyl succinic acid, 5%-15% oxidized wax ester, and 5-10% imidazoline amide type corrosion inhibitor.

[0027] The oiling agent is preferably any one or a combination of several of the following: castor oil polylactone, 12-hydroxystearic acid polylactone, dimer ester, trimer ester, and pentaerythritol ester of lanolin fatty acid.

[0028] Alcohol ether acid type surfactants are preferably structured as shown in formula (2):

[0029]

[0030] Where R' is a straight-chain or branched hydrocarbon group of C8 to C22, and m is an integer of 5 to 12.

[0031] The antioxidant is preferably any one or a combination of several of the following: 2,6-di-tert-butyl-p-cresol, 2,6-di-tert-butyl-p-(dimethylaminomethyl)phenol, 4,4'-methylene-bis-2,6-di-tert-butylphenol, and pentaerythritol tetrakis(β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid).

[0032] The preferred copper corrosion inhibitor is any one or a combination of several of the following: benzotriazole, methylbenzotriazole, benzotriazole Mannich condensate, methylbenzotriazole Mannich condensate, and thiadiazole derivatives.

[0033] The biodegradable base oil is preferably a synthetic ester base oil with a kinematic viscosity of 10 to 32 mm² / s at 40°C, and more preferably any one or a combination of diesters, neopentyl glycol esters and polyol esters with a kinematic viscosity of 10 to 32 mm² / s at 40°C.

[0034] The preparation method of the barium-free environmentally friendly electrostatic spraying rust-preventive oil of the present invention is as follows: 10%-20% of a composite barium-free rust inhibitor, 1%-3% of an oiliness agent, 0.5%-1.0% of an alcohol ether carboxylic acid surfactant, 0.2%-0.5% of an antioxidant, and 0.03%-0.1% of a copper corrosion inhibitor are added to a mixing tank in one step according to the proportions. The remainder is added to a biodegradable base oil, and the mixture is stirred thoroughly at room temperature until the composition is uniformly mixed to obtain the barium-free environmentally friendly electrostatic spraying rust-preventive oil.

[0035] The present invention will be further illustrated below through examples and experimental verification.

[0036] Example 1:

[0037] The components and contents of the barium-free environmentally friendly electrostatic spraying rust inhibitor provided in this embodiment are shown in Table 1. The composite barium-free rust inhibitor, based on its total weight of 100%, consists of 25% calcium petroleum sulfonate, 45% dinonylnaphthalene sulfonate, 10% dodecenyl succinic acid, 10% oxidized wax ester, and 10% imidazoline amide corrosion inhibitor.

[0038] The biodegradable base oil is a biodegradable pentaerythritol ester base oil with a kinematic viscosity of 28.44 mm at 40°C. 2 / s, pour point -60℃, biodegradability rate 85.9%.

[0039] Table 1 Example 1 Barium-free environmentally friendly electrostatic spraying rust-preventive oil

[0040]

[0041]

[0042] Add the above components and their amounts to the mixing vessel at once, and stir thoroughly at room temperature until the composition is uniformly mixed to obtain barium-free environmentally friendly electrostatic spray rust-preventive oil.

[0043] Example 2:

[0044] The components and contents of the barium-free environmentally friendly electrostatic spraying rust inhibitor provided in this embodiment are shown in Table 2. The composite barium-free rust inhibitor, based on its total weight of 100%, consists of 25% calcium petroleum sulfonate, 40% dinonylnaphthalene sulfonate, 15% dodecenyl succinic acid, 12% oxidized wax ester, and 8% imidazoline amide corrosion inhibitor.

[0045] Among them, the biodegradable synthetic ester base oil is a biodegradable trimethylolpropane ester base oil with a kinematic viscosity of 19.41 mm at 40°C. 2 / s, pour point -48℃, biodegradability 89.3%.

[0046] Table 2. Composition of Barium-Free Environmentally Friendly Electrostatic Spraying Rust-Preventive Oil (Example 2)

[0047] composition content Composite barium-free rust inhibitor 15.00％ 12-Hydroxystearic acid polylactone 2.00％ Oleyl alcohol polyoxyethylene ether carboxylic acid (10EO) 0.75％ 2,6-Di-tert-butyl-p-(dimethylaminomethyl)phenol 0.30％ Methylbenzotriazole 0.04％ Biodegradable synthetic ester base oils 81.91％

[0048] Add the above components and their amounts to the mixing vessel at once, and stir thoroughly at room temperature until the composition is uniformly mixed to obtain barium-free environmentally friendly electrostatic spray rust-preventive oil.

[0049] Example 3:

[0050] The components and contents of the barium-free environmentally friendly electrostatic spraying rust inhibitor provided in this embodiment are shown in Table 3. The composite barium-free rust inhibitor, based on its total weight of 100%, consists of 30% calcium petroleum sulfonate, 30% dinonylnaphthalene sulfonate, 20% dodecenyl succinic acid, 15% oxidized wax ester, and 5% imidazoline amide corrosion inhibitor.

[0051] Among them, the biodegradable synthetic ester base oil is a biodegradable neopentyl glycol ester base oil with a kinematic viscosity of 22.18 mmHg at 40°C. 2 / s, pour point -60℃, biodegradability 83.3%.

[0052] Table 3. Composition of Barium-Free Environmentally Friendly Electrostatic Spraying Rust-Preventive Oil (Example 3)

[0053] composition content Composite barium-free rust inhibitor 18.00％ Lanolin fatty acid pentaerythritol ester 1.50％ Oleyl alcohol polyoxyethylene ether carboxylic acid (5EO) 0.90％ 4,4'-Methylene-bis-2,6-di-tert-butylphenol 0.40％ benzotriazole Mannich condensate 0.05％ Biodegradable synthetic ester base oils 79.15％

[0054] Add the above components and their amounts to the mixing vessel at once, and stir thoroughly at room temperature until the composition is uniformly mixed to obtain barium-free environmentally friendly electrostatic spray rust-preventive oil.

[0055] Example 4:

[0056] The components and contents of the barium-free environmentally friendly electrostatic spraying rust inhibitor provided in this embodiment are shown in Table 4. The composite barium-free rust inhibitor, with its total weight as 100%, consists of 20% calcium petroleum sulfonate, 40% dinonylnaphthalene sulfonate, 25% dodecenyl succinic acid, 5% oxidized wax ester, and 10% imidazoline amide corrosion inhibitor.

[0057] Among them, the biodegradable synthetic ester base oil is a biodegradable diester base oil with a kinematic viscosity of 12.11 mm at 40°C. 2 / s, pour point -57℃, biodegradability 87.5% (OECD 301B).

[0058] Table 4. Composition of Barium-Free Environmentally Friendly Electrostatic Spraying Rust-Preventive Oil in Example 4

[0059]

[0060]

[0061] Add the above components and their amounts to the mixing vessel at once, and stir thoroughly at room temperature until the composition is uniformly mixed to obtain barium-free environmentally friendly electrostatic spray rust-preventive oil.

[0062] Comparative Example 1:

[0063] The difference between Comparative Example 1 and Example 4 lies in the substitution of barium petroleum sulfonate for calcium petroleum sulfonate in the composite barium-free rust inhibitor, the substitution of dinonylnaphthalene sulfonate for calcium dinonylnaphthalene sulfonate in the composite barium-free rust inhibitor, and the substitution of imidazoline amide corrosion inhibitor and oxidized wax ester for mineral base oil in the composite barium-free rust inhibitor. This demonstrates the effectiveness of imidazoline amide corrosion inhibitor and oxidized wax ester. Alkylphenol polyoxyethylene ether is substituted for alcohol ether carboxylic acid surfactant to demonstrate the effect of alcohol ether carboxylic acid surfactant on atomization and cleaning effects. Simultaneously, mineral base oil is substituted for biodegradable synthetic ester base oil to demonstrate the impact of biodegradable synthetic ester base oil on the environmental characteristics of the final rust-preventive oil product. The components and their contents are shown in Table 5.

[0064] The composite rust inhibitor, by weight 100%, consists of 20% barium petroleum sulfonate, 40% barium dinonylnaphthalene sulfonate, 25% dodecenyl succinic acid, and 15% No. 10 white oil.

[0065] The mineral base oil is No. 10 industrial white oil, with a kinematic viscosity of 10.62 mmHg at 40°C. 2 / s, pour point -18℃, biodegradability <60%.

[0066] Table 5. Composition of the rust-preventive oil composition in Comparative Example 1

[0067]

[0068]

[0069] Add the above components and amounts to the mixing vessel at once, and stir thoroughly at room temperature until the composition is evenly mixed to obtain the rust-preventive oil.

[0070] The physicochemical analysis and rust prevention performance evaluation results of Examples 1-4 and Comparative Example 1 are shown in Table 6:

[0071] Table 6

[0072]

[0073]

[0074]

[0075] As shown in Table 6, the physicochemical analysis results of Examples 1-4 and Comparative Example 1, including appearance, density, flash point, pour point, mechanical impurities, moisture, water-soluble acids and alkalis, separation stability, sprayability, cleanability, breakdown voltage, barium content, etc., as well as the evaluation results of four-ball wear test, corrosion test, damp heat test, salt spray test, and biodegradability test, are presented.

[0076] According to the experimental data of the flash point example, the composition of this application has a high flash point temperature, which is higher than the lowest temperature of immediate combustion in the comparative example, that is, the composition of this application has good storage stability.

[0077] According to the experimental data of the pour point example of the experimental project, it can be seen that the lowest temperature at which the cooled sample can flow is higher than that of the comparative example, that is, the low-temperature fluidity of this application is better.

[0078] The experimental data from the cleaning performance examples of the experimental project show that the composition of this application is easy to clean;

[0079] The experimental data from the breakdown voltage example of the experimental project show that the breakdown voltage is higher, which means that the application has a better anti-breakdown effect.

[0080] According to the experimental data of the barium content example, the barium content of this application is less than 10 ppm, which meets the environmental protection requirements of foreign environmental regulations that the anti-rust materials used in exported metal products must not contain barium, that is, it does not contain the heavy metal barium (barium content is less than 10 ppm).

[0081] According to Examples 1-4 in the table, the corrosion test was conducted at 55±1℃ for 168 hours according to SH / T 0081 standard. All 45# steel sheets were rated 0 and H62 copper sheets were rated 1, indicating that the rust-preventive oil of this application has very low corrosiveness.

[0082] According to the SH / T 0081-2000 standard, the 45# steel sheet and H62 copper sheet showed no rust after more than 144 hours of salt spray testing, indicating good salt spray resistance.

[0083] According to GB / T2361-1992 standard, the 45# steel sheet and H62 copper sheet showed no rust after 120 days of damp heat test, indicating good resistance to damp heat.

[0084] The present invention provides a barium-free, environmentally friendly electrostatic spray rust-preventive oil based on a composite barium-free rust inhibitor system containing biodegradable synthetic esters as base oil, alcohol ether carboxylic acids as surfactants, imidazoline amide corrosion inhibitors, and oxidized wax esters. This oil exhibits high breakdown voltage, good low-temperature fluidity, easy atomization, easy cleaning, and good storage stability. With a barium content below 10 ppm, it provides excellent rust prevention and lubrication, preventing the formation of contaminants or localized discoloration on metal surfaces. It also demonstrates good four-ball anti-wear performance and a biodegradability rate exceeding 70%. In contrast, the comparative examples using mineral oil as base oil, nonylphenol polyoxyethylene ether as surfactant, and composite barium salt as rust inhibitor exhibit inferior resistance to damp heat, salt spray, and four-ball extreme pressure anti-wear performance, as well as inferior cleanability compared to Examples 1-4.

Claims

1. A barium-free, environmentally friendly electrostatic spray rust-preventive oil, characterized in that, The composition by weight percentage is as follows: 10%-20% composite barium-free rust inhibitor, 1%-3% oiliness agent, 0.5%-1.0% alcohol ether carboxylic acid surfactant, 0.2%-0.5% antioxidant, 0.03%-0.1% copper corrosion inhibitor, and the balance being biodegradable base oil; The composite barium-free rust inhibitor is composed of the following components by mass percentage: 20%-30% calcium petroleum sulfonate, 30%-45% dinonylnaphthalene sulfonate, 10%-25% dodecenyl succinic acid, 5%-15% oxidized wax ester, and 5%-10% imidazoline amide type corrosion inhibitor, the sum of the above components by mass percentage is 100%; The general structural formula of the imidazoline amide type corrosion inhibitor is: （1） Where R is a straight-chain or branched hydrocarbon group of C10 to C21, and n is an integer from 0 to 2, and n is not 0.

2. The barium-free environmentally friendly electrostatic spraying rust-preventive oil according to claim 1, characterized in that, The general structural formula of the alcohol ether carboxylic acid type surfactant is: （2） Where R' is a straight-chain or branched hydrocarbon group of C8 to C22, and m is an integer of 5 to 12.

3. The barium-free environmentally friendly electrostatic spraying rust-preventive oil according to claim 1, characterized in that, The oiling agent is any one or a combination of several of the following: castor oil polylactone, 12-hydroxystearic acid polylactone, dimer ester, trimer ester, and pentaerythritol ester of lanolin fatty acids.

4. The barium-free environmentally friendly electrostatic spraying rust-preventive oil according to claim 1, characterized in that, The antioxidant is any one or a combination of several of the following: 2,6-di-tert-butyl-p-cresol, 2,6-di-tert-butyl-p-(dimethylaminomethyl)phenol, 4,4'-methylene-bis-2,6-di-tert-butylphenol, and pentaerythritol tetrakis(β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid).

5. The barium-free environmentally friendly electrostatic spraying rust-preventive oil according to claim 1, characterized in that, The copper corrosion inhibitor is any one or a combination of several of benzotriazole, methylbenzotriazole, benzotriazole Mannich condensate, methylbenzotriazole Mannich condensate, and thiadiazole derivatives.

6. The barium-free environmentally friendly electrostatic spraying rust-preventive oil according to claim 1, characterized in that, The biodegradable base oil has a kinematic viscosity of 10 mmHg at 40°C. 2 / s-32mm 2 Synthetic ester base oils with a biodegradability rate greater than 60% per second.

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