A release agent for micro-spraying, its preparation method and application

Abstract

The application provides a release agent for micro-spraying and a preparation method and application thereof, and the release agent comprises modified silicone oil 10-15 parts by weight, zinc dialkyldithiocarbamate 0.1-0.8 parts by weight, a compatibilizer 0.1-0.3 parts by weight and mineral oil 80-90 parts by weight. The release agent provided by the application has the advantages of high release performance, high release rate, small release agent dosage, small adhesion of a mold frame, small oil mist generation, high stability, good high-temperature resistance and the like when used in a micro-spraying process.

Description

Technical Field

[0001] This invention belongs to the field of casting processing, specifically relating to a release agent for micro-spraying, its preparation method and application, and particularly to a release agent for micro-spraying with high release rate, its preparation method and application. Background Technology

[0002] With the popularization of new energy vehicles, the aluminum alloy die-casting industry for vehicle bodies has developed rapidly. As an indispensable lubricating medium in the die-casting process, the amount of release agent used has increased accordingly, resulting in a large amount of waste liquid disposal problems. Some large die-casting companies have developed a micro-volume spraying production process. This process uses electrostatic spraying to apply release agent in extremely small quantities, thus significantly reducing waste liquid generation. In traditional processes, each 1L of release agent dilution produces approximately 0.3-0.5L of waste liquid, while the micro-volume spraying process produces less than 0.3L of waste liquid, demonstrating a significant advantage.

[0003] Micro-volume spraying offers advantages such as low release agent consumption and low wastewater production, making it a green and environmentally friendly production process with sustainable development significance. However, the development of release agents has not kept pace with the application needs of this process. Traditional release agents used in micro-volume spraying suffer from problems such as low adhesion, uneven distribution, and poor atomization, failing to truly realize the advantages of this process.

[0004] CN202111605606.4 discloses a casting hot core box release agent and its preparation method, comprising the following components by weight: 10-30 parts silicone oil, 5-12 parts emulsifier, 2-6 parts stabilizer, 0.5-3.5 parts defoamer, 0.1-1.0 parts corrosion inhibitor, and 50-90 parts water. The stabilizer is a mixture of heptadecafluorodecyltriethoxysilane and poloxamer. This technical solution solves the problems of existing release agents containing flammable solvents, poor stability, and limited release cycles. However, it does not solve the problems existing in micro-spraying processes.

[0005] CN201810341492.9 discloses a high-strength release agent and its preparation method, which is prepared from the following raw materials in parts by weight: 30-50 parts of fluorocarbon-modified silicone oil, 15-30 parts of polytetrafluoroethylene emulsion, 2-6 parts of N-lauroyl alanine, 3-5 parts of tall oil fatty acid, 1-4 parts of sodium nonylphenol polyoxyethylene ether (10) sulfate, 1-5 parts of dodecyl diphenyl ether disulfonic acid, 2-5 parts of glyceryl monostearate, 7-14 parts of composite inorganic filler, 5-10 parts of composite lubricant, 3-7 parts of dialkyl dithiophosphate antimony, 2-5 parts of dialkyl dithiocarbamate molybdenum, 1.5-3 parts of 3,5-di-tert-butyl-4-hydroxyphenylpropionate isooctyl ester, 2-7 parts of oil-based hydroxyethyl imidazoline, 1-3 parts of dioctyl sulfonated succinate, 3-8 parts of antioxidant, and 10-20 parts of solvent. This release agent exhibits good stability, abrasion resistance, and shear stability, and its preparation process is simple, making it suitable for widespread industrial applications. However, it also does not address the micro-spraying process and does not resolve the corresponding issues.

[0006] Since existing release agents have not solved a series of problems when used in micro-spraying processes, it has become an urgent problem to solve how to provide a release agent with high adhesion, uniform distribution and high release rate for micro-spraying processes. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the present invention aims to provide a release agent for micro-volume spraying, its preparation method, and its application, particularly a release agent with high release rate for micro-volume spraying, its preparation method, and its application. The release agent provided by the present invention, when used in micro-volume spraying processes, has the advantages of high release performance, high release rate, low release agent dosage, minimal mold frame adhesion, low oil mist generation, high stability, and good high-temperature resistance.

[0008] To achieve this objective, the present invention employs the following technical solution:

[0009] In a first aspect, the present invention provides a release agent for micro-spraying, the release agent comprising, by weight, 10-15 parts modified silicone oil, 0.1-0.8 parts zinc dialkyl dithiocarbamate, 0.1-0.3 parts compatibilizer, and 80-90 parts mineral oil.

[0010] The modified silicone oil can be in the following proportions: 10, 11, 12, 13, 14, or 15 parts; the zinc dialkyl dithiocarbamate can be in the following proportions: 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, or 0.8 parts; the compatibilizer can be in the following proportions: 0.1, 0.15, 0.2, 0.25, or 0.3 parts; and the mineral oil can be in the following proportions: 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, or 90 parts. However, these proportions are not limited to those listed above, and other unlisted proportions within the above range are also applicable.

[0011] The aforementioned release agent, through the synergistic effect of a specific modified silicone oil and zinc dialkyl dithiocarbamate, can effectively improve the high-temperature resistance and thermal stability of the product. At the same time, the selection of zinc dialkyl dithiocarbamate as a phosphorus-free extreme pressure agent makes it more environmentally friendly than other extreme pressure agents, and further improves the product's release properties and high-temperature resistance.

[0012] Preferably, the modified silicone oil has the following structure:

[0013]

[0014] Where R 1 It is a C1-C14 alkyl group, R 2 The aryl group is C6-C12 alkyl-substituted or unsubstituted, M is selected from sodium ion, potassium ion or ammonium ion; w is selected from integers of 15-25, x is selected from integers of 3-10, y is selected from integers of 0-16, z is selected from integers of 1-3, and n is selected from integers of 2-5.

[0015] Where w can be 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 or 25, x can be 3, 4, 5, 6, 7, 8, 9 or 10, y can be 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 or 16, z can be 1, 2 or 3, and n can be 2, 3, 4 or 5.

[0016] The C1-C14 alkyl groups can be, for example, methyl, ethyl, propyl, isopropyl, etc., and the C6-C12 alkyl groups, whether substituted or unsubstituted, can be, for example, phenyl, naphthyl, biphenyl, tolyl, ethylphenyl, etc.

[0017] The modified silicone oil with the above-mentioned specific structure improves the charge-carrying properties of the lubricant itself during the micro-spraying process by modifying the structure of alkylaryl silicone oil, so that it can be uniformly and directionally adsorbed on the mold surface, thereby increasing the amount of release agent attached, thus improving the release performance, reducing the amount of release agent used, reducing the spraying time, improving production efficiency, reducing mold frame adhesion, and reducing oil mist generation.

[0018] Preferably, the compatibilizer includes any one or a combination of at least two of hexanediol, octyl glycol, diethylene glycol dibutyl ether, diethylene glycol monobutyl ether, propylene glycol, glycerol, or sebacyl glycol, such as a combination of hexanediol and octyl glycol, a combination of octyl glycol and diethylene glycol dibutyl ether, or a combination of diethylene glycol dibutyl ether and propylene glycol, but is not limited to the combinations listed above. Other combinations not listed above are also applicable.

[0019] Preferably, the compatibilizer is a combination of hexanediol and octyl diester.

[0020] Preferably, the mass ratio of hexanediol to octyl diester is 1:1 to 1:1.4, such as 1:1, 1:1.1, 1:1.2, 1:1.3 or 1:1.4, but is not limited to the values ​​listed above. Other unlisted values ​​within the above range are also applicable.

[0021] Compared with other compatibilizers, the above-mentioned specific compatibilizers can further improve the dispersion and dissolution ability of silicone oil, enhance the stability and workability of the product, and further improve the compatibilization effect by controlling the component ratio.

[0022] Preferably, the mineral oil comprises paraffinic mineral oil and / or naphthenic mineral oil.

[0023] Preferably, the mineral oil has a kinematic viscosity of 2-10 mm at 40°C. 2 / s.

[0024] Preferably, the release agent further includes 0-0.05 parts by weight of fluorescent agent, but not 0 parts.

[0025] Among them, the kinematic viscosity of mineral oil at 40°C can be 2 mm. 2 / s, 3mm 2 / s, 4mm 2 / s, 5mm 2 / s, 6mm 2 / s, 7mm 2 / s, 8mm 2 / s, 9mm 2 / s or 10mm 2 / s, etc., the number of fluorescent agents can be 0.01 parts, 0.02 parts, 0.03 parts, 0.04 parts or 0.05 parts, etc., but not limited to the values ​​listed above. Other unlisted values ​​within the above range are also applicable.

[0026] Preferably, the fluorescent agent includes KSN and / or KCB.

[0027] Secondly, the present invention provides a method for preparing the release agent as described above, the method comprising the following steps:

[0028] Mineral oil and compatibilizer are mixed and stirred, then mixed with modified silicone oil and stirred until transparent. Next, it is mixed with zinc dialkyl dithiocarbamate and stirred until transparent to obtain the release agent.

[0029] Preferably, the process further includes mixing the fluorescent agent with the mineral oil before mixing and stirring the mineral oil and the compatibilizer.

[0030] Thirdly, the present invention also provides the application of the release agent as described above in the micro-spraying process of castings.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] This invention provides a release agent for micro-volume spraying, which has the advantages of high release performance, high release rate, low release agent dosage, low mold frame adhesion, low oil mist generation, high stability, and good high temperature resistance. Through the synergistic effect of a specific modified silicone oil and zinc dialkyl dithiocarbamate, the high temperature resistance and thermal stability of the product can be effectively improved. The use of a specifically structured modified silicone oil, by modifying the structure of the alkylaryl silicone oil, enhances the charge-carrying properties of the lubricant itself during micro-volume spraying, enabling it to be uniformly and directionally adsorbed onto the mold surface, thereby increasing the amount of release agent adhered, thus improving release performance, reducing release agent dosage, reducing spraying time, increasing production efficiency, reducing mold frame adhesion, and reducing oil mist generation. Furthermore, the selection of a specific compatibilizer, compared to other compatibilizers, can further effectively improve the dispersion and dissolution ability of the silicone oil, improving the stability and workability of the product. The compatibilization effect is further improved by controlling the component ratio. Detailed Implementation

[0033] To further illustrate the technical means and effects of the present invention, the following describes the technical solution of the present invention in conjunction with preferred embodiments of the present invention. However, the present invention is not limited to the scope of the embodiments.

[0034] Example 1

[0035] This embodiment provides a release agent for micro-spraying, the specific composition (by weight percentage) of which is as follows:

[0036] 12% modified silicone oil, 0.2% zinc dimethyl dithiocarbamate, 0.2% hexanediol and octyl diester (mass ratio 1:1.2), 0.02% KCB benzoxazole fluorescent agent, kinematic viscosity at 40℃ 5 mm. 2 / s of naphthenic mineral oil balance.

[0037] The modified silicone oil structure is as follows:

[0038]

[0039] Where R1 It is tetradecyl, R 2 The modified silicone oil is 2-phenylpropyl, w is 16, x is 8, y is 10, z is 2, n is 2, and M is sodium ion. The modified silicone oil was purchased from Qingdao Siliken New Materials Co., Ltd., and its model number is 9182Q.

[0040] The preparation method is as follows:

[0041] The fluorescent agent and mineral oil are mixed at 60°C to completely dissolve the fluorescent agent. A compatibilizer is added and stirred evenly. Modified silicone oil is added and stirred until uniform and transparent. Zinc dialkyl dithiocarbamate is added and stirred until uniform and transparent to obtain the release agent.

[0042] Example 2

[0043] This embodiment provides a release agent for micro-spraying, the specific composition (by weight percentage) of which is as follows:

[0044] 15% modified silicone oil, 0.1% zinc dimethyl dithiocarbamate, 0.3% hexanediol and octyl diester (mass ratio 1:1.2), 0.01% KCB benzoxazole fluorescent agent, kinematic viscosity at 40℃ 5 mm. 2 / s of naphthenic mineral oil balance.

[0045] The modified silicone oil structure is as follows:

[0046]

[0047] Where R 1 It is tetradecyl, R 2 The modified silicone oil is 2-phenylpropyl, w is 16, x is 8, y is 10, z is 2, n is 2, and M is sodium ion. The modified silicone oil was purchased from Qingdao Siliken New Materials Co., Ltd., and its model number is 9182Q.

[0048] The preparation method is the same as in Example 1.

[0049] Example 3

[0050] This embodiment provides a release agent for micro-spraying, the specific composition (by weight percentage) of which is as follows:

[0051] 15% modified silicone oil, 0.1% zinc dimethyl dithiocarbamate, 0.3% hexanediol and octyl diester (mass ratio 1:1.2), 0.01% KCB benzoxazole fluorescent agent, kinematic viscosity at 40℃ 5 mm. 2 / s of naphthenic mineral oil balance.

[0052] The modified silicone oil structure is as follows:

[0053]

[0054] Where R 1 It is n-dodecyl, R 2 The modified silicone oil is phenylethyl, w = 20, x = 6, y = 10, z = 2, n = 2, and M = sodium ion. It was purchased from Qingdao Siliken New Materials Co., Ltd. and its model number is 9181Q.

[0055] The preparation method is the same as in Example 1.

[0056] Example 4

[0057] This embodiment provides a release agent for micro-spraying. The specific composition is the same as in Example 1, except that the mass ratio of hexanediol to octyl glycol is 1:0.9.

[0058] The preparation method is the same as in Example 1.

[0059] Example 5

[0060] This embodiment provides a release agent for micro-spraying. The specific composition is the same as in Example 1, except that the mass ratio of hexanediol to octyl glycol is 1:1.5.

[0061] The preparation method is the same as in Example 1.

[0062] Example 6

[0063] This embodiment provides a release agent for micro-spraying, which is identical to that of Example 1 except that hexanediol is replaced with an equal amount of glycerol.

[0064] The preparation method is the same as in Example 1.

[0065] Example 7

[0066] This embodiment provides a release agent for micro-spraying, which is identical to that of Example 1 except that octyl diester is replaced with an equal amount of sebacyl diester.

[0067] The preparation method is the same as in Example 1.

[0068] Comparative Example 1

[0069] This embodiment provides a release agent for micro-spraying. The specific composition is the same as in Example 1, except that the modified silicone oil is replaced with an equal amount of ordinary alkylaryl silicone oil.

[0070] The structure of common alkylaryl silicone oil is as follows:

[0071]

[0072] The preparation method is the same as in Example 1.

[0073] Comparative Example 2

[0074] This embodiment provides a release agent for micro-spraying. The specific composition is the same as in Example 1, except that zinc dimethyl dithiocarbamate is not added and a portion is reduced in the modified silicone oil.

[0075] The preparation method is the same as in Example 1.

[0076] Comparative Example 3

[0077] This embodiment provides a release agent for micro-spraying. The specific composition is the same as in Example 1, except that zinc dimethyl dithiocarbamate is replaced with an equal amount of molybdenum dimethyl dithiocarbamate.

[0078] The preparation method is the same as in Example 1.

[0079] Comparative Example 4

[0080] A commercially available micro-spray release agent.

[0081] Performance testing:

[0082] The products provided in Examples 1-7 and Comparative Examples 1-4 were tested. The demolding rate, molding defect rate, carbon buildup on parts, carbon buildup on mold frames, nozzle blockage, smoke volume, hourly production volume, and waste liquid volume were obtained through actual production observation. The residue at 650°C was obtained by TGA thermogravimetric analysis, with the experimental temperature ranging from 30°C to 700°C. The results of placing the sample at 45°C for 2 months were obtained by visually inspecting the appearance after placing 200g of sample in a 45°C oven for 2 months.

[0083] The results are as follows:

[0084]

[0085]

[0086] The results above show that the product provided by this invention has excellent demolding performance and high-temperature resistance, while requiring less demolding agent, resulting in less mold frame adhesion and less oil mist. Comparing Example 1 and Examples 4-7, it can be seen that this invention, by selecting specific compatibilizers and controlling the relevant ratios, can effectively improve the compatibilization performance, thereby improving the demolding rate and yield of the product, increasing production volume and stability. Comparing Example 1 and Comparative Examples 1-2, it can be seen that this invention, by using a specific structurally modified silicone oil and zinc dialkyl dithiocarbamate in combination, achieves a synergistic effect, effectively improving the demolding rate and yield of the product, significantly reducing carbon buildup, generating less waste liquid, and significantly reducing oil mist generation, thus increasing production. Comparing Example 1 and Comparative Examples 3-4, it can be seen that this invention, by using specific zinc dialkyl dithiocarbamate compared to other phosphorus-free extreme pressure agents such as molybdenum dialkyl dithiocarbamate, and compared to existing technologies, significantly improves the performance of the product.

[0087] The applicant declares that this invention illustrates the release agent for micro-spraying, its preparation method, and its application through the above embodiments. However, this invention is not limited to the above embodiments, meaning that this invention does not necessarily rely on the above embodiments for implementation. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of the raw materials in the product, addition of auxiliary components, and selection of specific methods all fall within the protection and disclosure scope of this invention.

[0088] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0089] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

Claims

1. A release agent for micro-spraying, characterized in that, The release agent comprises, by weight, 10-15 parts modified silicone oil, 0.1-0.8 parts zinc dialkyl dithiocarbamate, 0.1-0.3 parts compatibilizer, and 80-90 parts mineral oil; The structure of the modified silicone oil is shown below: Where R 1 It is a C1-C14 alkyl group, R 2 The aryl group is C6-C12 alkyl-substituted or unsubstituted, M is selected from sodium ion, potassium ion or ammonium ion; w is selected from integers of 15-25, x is selected from integers of 3-10, y is selected from integers of 0-16, z is selected from integers of 1-3, and n is selected from integers of 2-5. The compatibilizer is a combination of hexanediol and octyl diester; The mass ratio of hexanediol to octyl diester is 1:1 to 1:1.

4.

2. The release agent according to claim 1, characterized in that, The mineral oil includes paraffinic mineral oil and / or naphthenic mineral oil.

3. The release agent according to claim 1, characterized in that, The mineral oil has a kinematic viscosity of 2-10 mm at 40°C. 2 / s.

4. The release agent according to claim 1, characterized in that, The release agent also includes 0-0.05 parts of fluorescent agent by weight, but does not include 0 parts.

5. The release agent according to claim 4, characterized in that, The fluorescent agents include KSN and / or KCB.

6. A method for preparing a release agent according to any one of claims 1-5, characterized in that, The preparation method includes the following steps: Mineral oil and compatibilizer are mixed and stirred, then mixed with modified silicone oil and stirred until transparent. Next, it is mixed with zinc dialkyl dithiocarbamate and stirred until transparent to obtain the release agent.

7. The preparation method according to claim 6, characterized in that, The process of mixing the mineral oil and compatibilizer before stirring also includes mixing the fluorescent agent with the mineral oil.

8. The application of a release agent according to any one of claims 1-5 in a micro-spraying process for castings.

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