Aluminum powder dispersant special for aluminum foil rolling oil and slurry leakage coating verification method and application

Abstract

The application belongs to the technical field of materials, and discloses a special aluminum powder dispersing agent for aluminum foil rolling oil, which is composed of the following components and in the following proportions: base oil: 10-20 parts; surfactant: oleic acid diethanol amide: 40-60 parts; fatty amine polyoxyethylene ether: 10-30 parts; lubricating cleaner: dimer acid: 5-15 parts; and guerbet alcohol: 10-20 parts. The aluminum powder dispersing agent adopts oleic acid diethanol amide and T13 surfactant which have sufficient dispersion effect on aluminum powder, so as to reduce the pollution caused by aluminum powder accumulation after rolling of the aluminum foil; through introduction of the dimer acid and the guerbet alcohol, the lubricating performance of the rolling oil is improved, the oil amount on the surface of the aluminum foil after rolling is reduced, the surface cleanliness of the aluminum foil is improved, and thus the surface leakage coating condition of the aluminum foil is improved.

Description

Technical Field

[0001] This invention belongs to the field of materials technology, and in particular to a special aluminum powder dispersant for aluminum foil rolling oil and a method and application for verifying slurry leakage. Background Technology

[0002] With the promotion of new energy technologies, the requirements for aluminum foil in positive electrode current collectors are becoming increasingly stringent. Generally, during the rolling process, aluminum powder is continuously rolled out and gradually accumulates on the surface of the aluminum foil, causing surface contamination. At the same time, in order to increase the lubricity of the rolling oil, many long-chain fatty alcohols and synthetic esters are introduced into the additives. These additive components remain on the surface of the aluminum foil after rolling, increasing the oil content and causing a decrease in dyne value. During slurry coating, incomplete coating often occurs. Depending on the amount and location of the oil on the surface, common incomplete coating phenomena include dot-like, spindle-shaped, and cloud-like incomplete coating. In addition, during the aluminum foil rolling process, the continuous rolling of the aluminum foil by the two rollers inevitably produces a large amount of aluminum powder. When the aluminum powder is incorporated into the rolling oil system, it is likely to adhere to the surface of the aluminum foil as rolling continues, causing patchy aluminum powder coverage. This is also an important factor leading to incomplete coating during slurry coating. Incomplete aluminum foil slurry coating will greatly reduce the production efficiency of the positive electrode current collector, causing headaches for major battery manufacturers.

[0003] To improve the situation of slurry coating leakage, it is urgent to develop an aluminum foil rolling oil dispersant that can improve the dispersibility of aluminum powder in rolling oil and the cleanliness of aluminum foil surface, improve lubrication, reduce oil carryover, and use effective oil carryover verification methods to determine the improvement of coating leakage, thereby improving the production efficiency of positive electrode current collector.

[0004] The search revealed the following patent publications related to this invention's patent application:

[0005] 1. Patent publication CN126078819A describes a method for improving the dyne value of a battery foil surface, which mentions using a base oil, alcohol, ester, and dyne solution to improve the dyne value and surface wetting tension of the battery foil surface.

[0006] 2. Patent publication CN113444559A discloses a battery foil rolling additive, its preparation method, and its application. It mentions using a combination of fatty acid esters, fatty alcohols, adamantane compounds, and extreme pressure additives to improve the surface dyne value of the battery foil and reduce the cost of the corona treatment process. Simultaneously, the use of the battery foil rolling additive is beneficial for improving the dispersion performance and filtration efficiency of aluminum powder, and improving the cleaning performance of the rolling mill.

[0007] 3. Patent publication CN113385536A discloses a method for producing battery aluminum foil with improved surface dyne value. It mentions the use of rolling oil in the roughing, intermediate, and finishing rolling steps. The rolling oil is obtained by adding additives and auxiliaries to white oil and mixing them thoroughly. The battery aluminum foil obtained by this invention has a high surface dyne value, and the surface dyne value maintains good stability.

[0008] 4. Patent publication CN116024030A: An additive for rolling power battery foil, its preparation method and application. By selecting isoparaffinic tackifiers as base oil, the concentration of composite additives is only 20%-30%, which greatly reduces the probability of missing coating of the rolled battery foil.

[0009] These patent publications only improve the dyne value of aluminum foil surface by optimizing the formula or verifying the coating effect of the slurry by roller coating. This invention introduces an aluminum powder dispersant into the widely used aluminum foil rolling oil formula that has been published and implemented. Relying on the synergistic effect of each raw material, it improves the aluminum powder dispersion performance during the rolling process, reduces the amount of oil on the aluminum foil surface, and thus improves the cleanliness of the aluminum foil surface. This is of great help in improving or even solving the problem of missing coating of aluminum foil slurry. Furthermore, the missing coating situation is verified by testing the amount of oil on the aluminum foil, which is fundamentally different from the aforementioned patent publications. Summary of the Invention

[0010] The purpose of this invention is to overcome the shortcomings of the prior art and provide a special aluminum powder dispersant for aluminum foil rolling oil and a method and application for verifying slurry leakage.

[0011] The technical solution adopted by this invention to solve its technical problem is:

[0012] An aluminum powder dispersant for aluminum foil rolling oil, the composition and weight parts of which are as follows:

[0013] Base oil: 10-20 parts;

[0014] Surfactants: oleic acid diethanolamide: 40-60 parts; fatty amine polyoxyethylene ether: 10-30 parts;

[0015] Lubricating and cleaning agents: dimer acid: 5-15 parts; Gerbert alcohol: 10-20 parts.

[0016] Furthermore, the base oil is a commonly used D80 type rolling oil (mixed dodecane);

[0017] The fatty amine polyoxyethylene ether is T13.

[0018] Furthermore, the Gerbert alcohol is Gerbert alcohol. C16, It is a saturated primary alcohol with a specific C2-branched structure, namely Guerbert alcohol, produced by Sasol in Germany. Its structural formula is as follows:

[0019]

[0020] The preparation method of the aluminum powder dispersant for aluminum foil rolling oil as described above includes the following steps:

[0021] (1) Weigh the base oil, surfactant, and lubricating cleaner according to the mass ratio;

[0022] (2) Heat the mixing tank to 40-60℃, add base oil and surfactant in sequence, start stirring, speed 100-200r / min, time 45-60min; then add lubricating cleaner, continue stirring for 30-60min to obtain aluminum powder dispersant for aluminum foil rolling oil.

[0023] The method of using the aluminum powder dispersant for aluminum foil rolling oil as described above includes the following steps:

[0024] It is added directly to the aluminum foil rolling oil, and the final mass concentration of the special aluminum powder dispersant is 1-3%.

[0025] The application of aluminum powder dispersants as described above in the preparation of aluminum foil rolling oil.

[0026] Aluminum foil rolling oil containing the aluminum powder dispersant specifically for aluminum foil rolling oil as described above.

[0027] The method for verifying the aluminum powder dispersibility of aluminum foil rolling oil as described above includes the following steps:

[0028] (1) Rinse the dried stoppered measuring cylinder with the rolling oil to be tested at room temperature;

[0029] (2) Add 25ml±1ml of the test rolling oil at room temperature to a stoppered graduated cylinder;

[0030] (3) Use a spatula to slowly crush the aluminum powder and weigh 1g ± 0.01g of aluminum powder with a particle size of less than 1um into a stoppered graduated cylinder;

[0031] (4) After inserting the stopper, after 5 minutes, shake it up and down 30cm 20 times, and then rotate it 360 degrees in a plane 5 times.

[0032] (5) Place the prepared aluminum sheet in the container, keeping the aluminum sheet vertical;

[0033] (6) Place the stoppered graduated cylinder on the test bench and immediately record the observed phenomena, namely, the settling speed, cohesion, and wall adhesion of aluminum powder.

[0034] (7) Observe and record the phenomenon once every 2 hours. After the aluminum powder has completely settled, record the adhesion of the aluminum powder on the aluminum plate.

[0035] The method for testing the amount of oil on the surface of aluminum foil after rolling using the aluminum foil rolling oil described above includes the following steps:

[0036] The amount of oil on the surface of aluminum foil is measured by the weight loss method, which reflects the extent of slurry leakage. The details are as follows:

[0037] (1) Cut the aluminum foil into pieces of the same size and record the area S in meters. 2 Weigh the sample and record the weight as m1, in mg.

[0038] (2) Place it in an oven, set the temperature to 150℃, and the time to 30 minutes;

[0039] (3) After removing the aluminum foil, place it in a desiccator to cool to room temperature and weigh it. Record the weight in m2 (mg).

[0040] (4) Formula for oil carrying capacity: (m2-m1) / S, unit: mg / m 2 .

[0041] The advantages and positive effects of this invention are as follows:

[0042] 1. The aluminum powder dispersant of this invention uses oleic acid diethanolamide and T13 surfactant, which have a sufficient dispersing effect on aluminum powder, to reduce the contamination caused by aluminum powder accumulation after aluminum foil rolling; by introducing dimer acid and Guerbert alcohol, the lubricating performance of the rolling oil is increased, the amount of oil on the surface of the aluminum foil after rolling is reduced, the surface cleanliness of the aluminum foil is improved, and thus the problem of missing coating on the aluminum foil surface is improved.

[0043] 2. By adding the aluminum powder dispersant of this invention to the aluminum foil rolling oil, the aluminum powder is fully dispersed in the rolling oil during the rolling process, ensuring that there is no excessive aluminum powder residue on the aluminum foil surface. At the same time, it effectively reduces the amount of oil on the surface, keeping the aluminum foil clean, thereby achieving effective coating of the slurry on the aluminum foil surface. Furthermore, by using effective verification methods, it is possible to determine the situation of slurry leakage.

[0044] 3. In the past, rolling lubricant additives only improved lubricity and the dyne value of aluminum foil surface by adjusting the basic formula, but did not fundamentally solve the problems of aluminum foil surface contamination and excessive oil content caused by aluminum powder accumulation during the rolling process. This invention adds an aluminum powder dispersant to the rolling oil, so that the aluminum powder is fully dispersed in the rolling oil during the rolling process, and reduces the amount of oil on the aluminum foil surface, improves the cleanliness of the aluminum foil surface, and effectively improves the slurry coating leakage.

[0045] 4. Dyne values ​​alone cannot accurately determine the extent of aluminum foil slurry coating defects. This invention uses the weight loss method to test the amount of oil in the aluminum foil slurry before coating, and infers the extent of coating defects based on the amount of oil. This comprehensive evaluation more accurately verifies whether aluminum foil will have coating defects after rolling and leaving the factory, reduces the yield of defective products, and improves slurry coating efficiency. Attached Figure Description

[0046] Figure 1 This is a photograph taken after 24 hours of aluminum powder dispersibility testing on the aluminum powder dispersant for aluminum foil rolling oil in this invention. Detailed Implementation

[0047] The present invention will be further described below with reference to the embodiments. The following embodiments are descriptive and not limiting, and should not be used to limit the scope of protection of the present invention.

[0048] The various experimental operations involved in the specific embodiments are all conventional techniques in the field. For parts not specifically annotated in this document, those skilled in the art can refer to various commonly used reference books, scientific and technological documents or related instructions and manuals prior to the filing date of this invention to carry out the operations.

[0049] An aluminum powder dispersant for aluminum foil rolling oil, the composition and weight parts of which are as follows:

[0050] Base oil: 10-20 parts;

[0051] Surfactants: oleic acid diethanolamide: 40-60 parts; fatty amine polyoxyethylene ether: 10-30 parts;

[0052] Lubricating and cleaning agents: dimer acid: 5-15 parts; Gerbert alcohol: 10-20 parts.

[0053] Preferably, the base oil is a commonly used D80 type rolling oil (mixed dodecane);

[0054] The fatty amine polyoxyethylene ether is T13.

[0055] Preferably, the Gerbert alcohol is Gerbert alcohol. C16, It is a saturated primary alcohol with a specific C2-branched structure, namely Guerbert alcohol, produced by Sasol in Germany. Its structural formula is as follows:

[0056]

[0057] The preparation method of the aluminum powder dispersant for aluminum foil rolling oil as described above includes the following steps:

[0058] (1) Weigh the base oil, surfactant, and lubricating cleaner according to the mass ratio;

[0059] (2) Heat the mixing tank to 40-60℃, add base oil and surfactant in sequence, start stirring, speed 100-200r / min, time 45-60min; then add lubricating cleaner, continue stirring for 30-60min to obtain aluminum powder dispersant for aluminum foil rolling oil.

[0060] The method of using the aluminum powder dispersant for aluminum foil rolling oil as described above includes the following steps:

[0061] It is added directly to the aluminum foil rolling oil, and the final mass concentration of the special aluminum powder dispersant is 1-3%.

[0062] The application of aluminum powder dispersants as described above in the preparation of aluminum foil rolling oil.

[0063] Aluminum foil rolling oil containing the aluminum powder dispersant specifically for aluminum foil rolling oil as described above.

[0064] The method for verifying the aluminum powder dispersibility of aluminum foil rolling oil as described above includes the following steps:

[0065] (1) Rinse the dried stoppered measuring cylinder with the rolling oil to be tested at room temperature;

[0066] (2) Add 25ml±1ml of the test rolling oil at room temperature to a stoppered graduated cylinder;

[0067] (3) Use a spatula to slowly crush the aluminum powder and weigh 1g ± 0.01g of aluminum powder with a particle size of less than 1um into a stoppered graduated cylinder;

[0068] (4) After inserting the stopper, after 5 minutes, shake it up and down 30cm 20 times, and then rotate it 360 degrees in a plane 5 times.

[0069] (5) Place the prepared aluminum sheet in the container, keeping the aluminum sheet vertical;

[0070] (6) Place the stoppered graduated cylinder on the test bench and immediately record the observed phenomena, namely, the settling speed, cohesion, and wall adhesion of aluminum powder.

[0071] (7) Observe and record the phenomenon every 2 hours until the aluminum powder has completely settled, and then record the adhesion of the aluminum powder to the aluminum plate. The test method for the amount of oil on the surface of aluminum foil after rolling using the aluminum foil rolling oil as described above includes the following steps: measuring the amount of oil on the surface of the aluminum foil by the weight loss method, thereby reflecting the situation of slurry leakage, as follows:

[0072] (1) Cut the aluminum foil into pieces of the same size and record the area S in meters. 2 Weigh the sample and record the weight as m1, in mg.

[0073] (2) Place it in an oven, set the temperature to 150℃, and the time to 30 minutes;

[0074] (3) After removing the aluminum foil, place it in a desiccator to cool to room temperature and weigh it. Record the weight in m2 (mg).

[0075] (4) Formula for oil carrying capacity: (m2-m1) / S, unit: mg / m 2 .

[0076] Specifically, the relevant preparation and testing methods are as follows:

[0077] Example 1

[0078] An aluminum powder dispersant for aluminum foil rolling oil, the composition and weight parts of which are as follows:

[0079] (1) Base oil D80: 10 parts;

[0080] (2) Oleic acid diethanolamide: 60 parts;

[0081] (3) T13: 10 portions;

[0082] (4) Dimeric acid: 10 parts;

[0083] (5) C16: 10 copies.

[0084] Example 2

[0085] An aluminum powder dispersant for aluminum foil rolling oil, the composition and weight parts of which are as follows:

[0086] (1) Base oil D80: 10 parts;

[0087] (2) Oleic acid diethanolamide: 40 parts;

[0088] (3) T13: 30 portions;

[0089] (4) Dimeric acid: 10 parts;

[0090] (5) C16: 10 copies.

[0091] Example 3

[0092] An aluminum powder dispersant for aluminum foil rolling oil, the composition and weight parts of which are as follows:

[0093] (1) Base oil D80: 10 parts;

[0094] (2) Oleic acid diethanolamide: 50 parts;

[0095] (3) T13: 20 portions;

[0096] (4) Dimeric acid: 10 parts;

[0097] (5) C16: 10 copies.

[0098] Comparative Example 1

[0099] An aluminum powder dispersant for aluminum foil rolling oil, the composition and weight parts of which are as follows:

[0100] (1) Base oil D80: 10 parts;

[0101] (2) AEO3: 70 copies;

[0102] (3) Dimeric acid: 10 parts;

[0103] (4) C16: 10 copies.

[0104] Comparative Example 2

[0105] An aluminum powder dispersant for aluminum foil rolling oil, the composition and weight parts of which are as follows:

[0106] (1) Base oil D80: 10 parts;

[0107] (2) Oleic acid diethanolamide: 60 parts;

[0108] (3) T13: 10 portions;

[0109] (4) Lauric acid: 20 parts.

[0110] The preparation methods for the above three examples and two comparative examples are as follows:

[0111] (1) Weigh the base oil, surfactant, and lubricating cleaner according to the mass ratio;

[0112] (2) Heat the stirring vessel to 50°C, add base oil and surfactant in sequence, start stirring, speed 100r / min, time 60min, then add lubricating cleaner, continue stirring for 30min, and you can get aluminum foil rolling oil aluminum powder dispersant.

[0113] The relevant tests are as follows:

[0114] I. Testing of Key Technical Indicators for Various Rolling Oils

[0115] The above three examples and two comparative examples were added to a certain aluminum foil rolling oil at a ratio of 2% (additive (i.e., the aluminum powder dispersant for aluminum foil rolling oil of this invention) ratio: 2% by mass concentration; rolling oil ratio: 98% by mass concentration). To compare the experimental results, rolling oil without the aluminum powder dispersant was set as a blank sample. Technical indicators of all examples and comparative examples were tested. These three rolling oils were applied to a small rolling mill in an aluminum plant to prepare 1070A aluminum foil. Afterwards, the oil content was tested according to the method for verifying coating leakage of this invention. The main technical indicators of each rolling oil are shown in Table 2. Figure 1 As shown:

[0116] Table 2 Main Technical Indicators of Each Rolling Oil

[0117]

[0118] The following conclusions can be drawn from comparing the experimental results in Table 2:

[0119] Compared with rolling oil A / B / C / F, the addition of aluminum powder dispersant has a significant effect on the dyne value of aluminum foil surface and the dispersibility of aluminum powder in rolling oil. At the same time, by introducing raw materials with lubricating and aluminum foil surface cleaning effects into the dispersant, the coefficient of friction and surface oil content are significantly reduced, which greatly helps to improve the surface cleanliness of aluminum foil.

[0120] Comparing A and D, both involve the addition of surfactants. However, choosing an AEO3 type surfactant fails to achieve uniform dispersion of aluminum powder. Furthermore, comparing the surface dyne value and oil content reveals that the addition of the surfactant specified in this invention results in both the dyne value and oil content being superior to that of rolling oil containing AEO3 surfactant. Therefore, it is concluded that the surfactant of this invention is the best choice for dispersing aluminum powder and improving the oil content on the surface of aluminum foil.

[0121] Comparing A and E, both use the same surfactant but different materials for the lubricant and cleaner. It was found that after adding the lubricant and cleaner specified in this invention, the extreme pressure Pb value and friction coefficient of rolling oil A were better than those of rolling oil E, which used only lauric acid as the lubricant and cleaner. It was concluded that the lubricant and cleaner of this invention has an excellent extreme pressure lubrication effect during the rolling process.

[0122] Meanwhile, by comparing Example 1, Comparative Example 1, and Comparative Example 2, it can be seen that the surfactant and lubricating cleaner in this invention have a synergistic effect, which can synergistically improve the relevant properties of the aluminum powder dispersant for aluminum foil rolling oil, especially 60 parts by weight of oleic acid diethanolamide, 10 parts by weight of T13, 10 parts by weight of dimer acid, and 10 parts by weight of [unclear text - possibly a specific ingredient or component]. They exhibit a significant synergistic effect, which can synergistically improve the relevant properties of the prepared aluminum powder dispersant for aluminum foil rolling oil.

[0123] II. Inspection of Coating Defects in Aluminum Coils After Rolling with Various Rolling Oils

[0124] The aluminum coils rolled with the above six types of rolling oil were coated using a small slurry coating machine in a battery factory. The missing coating rate was calculated based on the missing coating area, and the conclusions are shown in Table 3.

[0125] The amount of oil on the surface of aluminum foil is measured by the weight loss method, which reflects the extent of slurry leakage. The details are as follows:

[0126] (1) Cut the aluminum foil into pieces of the same size and record the area S in meters. 2 Weigh the sample and record the weight as m1, in mg.

[0127] (2) Place it in an oven, set the temperature to 150℃, and the time to 30 minutes;

[0128] (3) After removing the aluminum foil, place it in a desiccator to cool to room temperature and weigh it. Record the weight in m2 (mg).

[0129] (4) Formula for oil carrying capacity: (m2-m1) / S, unit: mg / m 2 .

[0130] Table 3. Coating defects of aluminum coils after rolling with various rolling oils.

[0131]

[0132] The conclusions in Table 3 also demonstrate that it is reasonable and effective to verify the coating leakage based on the amount of oil used in this invention.

[0133] In summary, Example 1 is the most effective in improving rolling lubrication and aluminum foil surface cleanliness, as well as reducing the rate of missed coating.

[0134] Although embodiments of the invention have been disclosed for illustrative purposes, those skilled in the art will understand that various substitutions, variations, and modifications are possible without departing from the spirit and scope of the invention and the appended claims. Therefore, the scope of the invention is not limited to the contents disclosed in the embodiments.

Claims

1. A special aluminum powder dispersant for aluminum foil rolling oil, characterized in that: Its composition and weight percentages are as follows: Base oil: 10-20 parts; Surfactants: oleic acid diethanolamide: 40-60 parts; fatty amine polyoxyethylene ether: 10-30 parts; Lubricating and cleaning agents: Dimer acid: 5-15 parts; Gelbert alcohol: 10-20 parts; The base oil is a mixture of dodecane; The fatty amine polyoxyethylene ether is T13; The Gerbert alcohol is Gerbert alcohol ISOFOL® C16, and its structural formula is as follows: 。 2. The preparation method of the aluminum powder dispersant for aluminum foil rolling oil as described in claim 1, characterized in that: Includes the following steps: (1) Weigh the base oil, surfactant, and lubricant / cleaner according to the mass ratio; (2) Heat the mixing vessel to 40-60℃, add base oil and surfactant in sequence, start stirring, speed 100-200r / min, time 45-60min; then add lubricating cleaner, continue stirring for 30-60min to obtain aluminum powder dispersant for aluminum foil rolling oil.

3. The method of using the aluminum powder dispersant for aluminum foil rolling oil as described in claim 1 in aluminum foil rolling oil, characterized in that: Includes the following steps: It is added directly to the aluminum foil rolling oil, and the final mass concentration of the special aluminum powder dispersant is 1-3%.

4. The application of the aluminum powder dispersant as described in claim 1 in the preparation of aluminum foil rolling oil.

5. An aluminum foil rolling oil containing the aluminum powder dispersant as described in claim 1.

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