High-temperature-resistant sealing agent and preparation method thereof

Abstract

The invention discloses a high-temperature-resistant sealing agent and a preparation method thereof, and relates to the technical field of chemical assistants, and the high-temperature-resistant sealing agent is characterized by comprising the following components in parts by weight: 25-32 parts of acidic nano silica sol, 56-65 parts of a cosolvent, 8-12 parts of a hydrolysis inhibitor, 9-12 parts of a silane coupling agent A, 5.5-6.8 parts of a silane coupling agent B and 0.01-0.015 part of a wetting agent. The high-temperature-resistant sealing agent has the effects that the high-temperature-resistant sealing agent is not yellowed, decomposed and dropped after being baked for 2 hours in an oven at the temperature of 250 DEG C, and is not corroded after being corroded by salt mist for 1000 hours.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of chemical additives, and more particularly to a high-temperature-resistant sealing agent and a preparation method thereof. BACKGROUND

[0002] In many industrial fields such as metal processing, electronic device manufacturing, aerospace, etc., sealing agents play a crucial role. It can perform sealing treatment on the surface of the material to prevent moisture, oxygen, corrosive media in the external environment from eroding the material, thereby improving the service life and performance stability of the material. However, in some high-temperature environments, the existing sealing agents often cannot meet the use requirements.

[0003] In the electroplating industry, in order to remove hydrogen brittleness, a high-temperature baking process is usually required. For zinc-plated components, generally, constant temperature of 220℃ is maintained for 4h. In this process, traditional sealing agents, such as traditional resin-type sealing agents, are not resistant to high temperature and are prone to decomposition, carbonization, etc., resulting in failure of their sealing performance, which cannot protect the metal plating layer and the passivation layer, and need to be improved. SUMMARY

[0004] In view of the deficiencies in the prior art, the first object of the present application is to provide a high-temperature-resistant sealing agent and a preparation method thereof, which have the effects of high-temperature resistance, high water solubility, high stability, and low cost.

[0005] To achieve the above object, the present application provides the following technical solutions: A high-temperature-resistant sealing agent comprises, by weight parts, 25-32 parts of acid nano-silica sol, 56-65 parts of a cosolvent, 8-12 parts of a hydrolysis inhibitor, 9-12 parts of a silane coupling agent A, 5.5-6.8 parts of a silane coupling agent B, and 0.01-0.015 parts of a wetting agent; wherein the silane coupling agent B is phenyl-modified γ-aminopropyl triethoxysilane.

[0006] Preferably, the acid nano-silica sol comprises 25% by mass of silicon dioxide, and the particle size of the silicon dioxide is less than 20nm.

[0007] Preferably, the cosolvent is isopropyl alcohol, the hydrolysis inhibitor is 1,2-propanediol, and the silane coupling agent A is 3-(2,3-epoxypropoxy) propyl trimethoxysilane.

[0008] Preferably, the cosolvent is isopropyl alcohol, the hydrolysis inhibitor is 1,2-propanediol, and the silane coupling agent A is 3-(2,3-epoxypropoxy) propyl trimethoxysilane.

[0009] Preferably: the wetting agent is C13-carbonyl alcohol ethoxylate, and the C13-carbonyl alcohol ethoxylate is a wetting agent Lutensol TO5 purchased from BASF.

[0010] A second object of the present application is to provide a preparation method of a high-temperature-resistant sealing agent, for preparing the high-temperature-resistant sealing agent as described above, mixing, stirring and standing acid nano-silica sol, cosolvent, hydrolysis inhibitor, silane coupling agent A, silane coupling agent B and wetting agent by weight parts.

[0011] Preferably: the high-temperature-resistant sealing agent does not yellow, decompose and fall off based on 2 hours of baking in an oven at 250℃.

[0012] Preferably: the high-temperature-resistant sealing agent does not corrode based on 1000 hours of salt spray corrosion.

[0013] Preferably: the preparation method of the phenyl-modified gamma-aminopropyl triethoxysilane comprises the following steps: Step 1, pretreatment: take 90-110 parts of gamma-aminopropyl triethoxysilane by weight into a three-necked flask, and stir in a constant temperature water bath at 50±2℃ under nitrogen protection for 28-32min; Step 2, grafting treatment: add 20-25 parts of 1,3-dimethylphenyl trimethoxysilane and 0.6-0.9 parts of catalyst stannous octoate by weight dropwise into the three-necked flask, control the dropwise speed to be 1 drop / s, after the dropwise addition is completed, increase the temperature to 83-87℃, and keep stirring for 4.5 hours to obtain modified material; Step 3, purification treatment: distill the modified material under vacuum for 1-1.2h, control the distillation temperature to be 73-77℃, and the distillation time to be 1.2-1.3 hours to obtain purified modified crude product; Step 4, neutralization and stabilization: add glacial acetic acid to adjust the pH of the purified modified crude product to 5-6, stir for 15min, and dilute and stir with anhydrous ethanol to obtain a stable modified silane coupling agent.

[0014] As can be seen from the above scheme, the present application provides a high-temperature-resistant sealing agent and a preparation method thereof. The high-temperature-resistant sealing agent and the preparation method thereof have the following beneficial effects: resistant to high-temperature environment, no yellowing, decomposition and other phenomena occur at high temperature, maintain good sealing performance, protect the surface of the treated material, and at the same time have good water solubility, stability and low cost, thereby meeting the needs of different industrial fields for high-temperature-resistant sealing agents. DETAILED DESCRIPTION

[0015] In order to make the technical solutions and advantages of the present application clearer, the present application will be further described in detail below. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0016] A high-temperature-resistant sealing agent and a preparation method thereof will be specifically described below.

[0017] A high-temperature-resistant sealing agent comprises 25-32 parts by weight of acidic nanosilica sol, 56-65 parts by weight of a cosolvent, 8-12 parts by weight of a hydrolysis inhibitor, 9-12 parts by weight of a silane coupling agent A, 5.5-6.8 parts by weight of a silane coupling agent B, and 0.01-0.015 parts by weight of a wetting agent. The silane coupling agent B is phenyl-modified γ-aminopropyl triethoxysilane. The acidic nanosilica sol comprises 25% by mass of silicon dioxide, the particle size of the silicon dioxide is less than 20 nm, and the pH of the acidic nanosilica sol is 3.

[0018] It should be noted that the cosolvent is isopropyl alcohol, the hydrolysis inhibitor is 1,2-propanediol, the silane coupling agent A is 3-(2,3-epoxypropoxy) propyl trimethoxysilane, and the wetting agent is C13-carbonyl alcohol ethoxylate, which is a wetting agent Lutensol TO5 purchased from BASF.

[0019] The preparation method of the phenyl-modified γ-aminopropyl triethoxysilane comprises the following steps: Step 1, pretreatment: 90-110 parts by weight of γ-aminopropyl triethoxysilane is placed in a three-necked flask, and stirred in a constant-temperature water bath at 50±2℃ under nitrogen protection for 28-32 min; Step 2, grafting treatment: 20-25 parts by weight of 1,3-xylene trimethoxysilane and 0.6-0.9 parts by weight of a catalyst stannous octoate are added dropwise into the three-necked flask, the dropwise speed is controlled to be 1 drop / s, after the dropwise addition is completed, the temperature is raised to 83-87℃, and the modified material is obtained by stirring for 4.5 hours; Step 3, purification treatment: the modified material is distilled under vacuum for 1-1.2 hours, the distillation temperature is controlled to be 73-77℃, and the distillation time is controlled to be 1.2-1.3 hours, to obtain a purified modified crude product; Step 4, neutralization and stabilization: glacial acetic acid is added to the purified modified crude product to adjust the pH to 5-6, stirring for 15 min, and then diluting and stirring with anhydrous ethanol to obtain a stable modified silane coupling agent.

[0020] A preparation method of a high-temperature-resistant sealing agent, for preparing the high-temperature-resistant sealing agent as described above, taking acid nano-silica sol, cosolvent, hydrolysis inhibitor, silane coupling agent A, silane coupling agent B, and wetting agent by weight parts, mixing, stirring and standing. Among them, the high-temperature-resistant sealing agent in the embodiment of the application is not yellow, decomposed and peeled off based on 2 hours of baking in an oven at 250°C. At the same time, the high-temperature-resistant sealing agent is not corroded based on 1000 hours of salt spray corrosion. Embodiment

[0021] A high-temperature-resistant sealing agent, including 25 parts by weight of acid nano-silica sol, 56 parts of isopropyl alcohol, 8 parts of 1,2-propanediol, 9 parts of 3-(2,3-epoxypropoxy) propyl trimethoxysilane, 5.5 parts of phenyl modified gamma-aminopropyl triethoxysilane, and 0.01 parts of wetting agent Lutensol TO5. Among them, the acid nano-silica sol includes 25% of silicon dioxide by mass percentage, and the particle size of the silicon dioxide is less than 20 nm, and the pH of the acid nano-silica sol is 3.

[0022] A preparation method of phenyl modified gamma-aminopropyl triethoxysilane includes the following steps: Step 1, pretreatment: taking 90 parts by weight of gamma-aminopropyl triethoxysilane in a three-necked flask, stirring in a 48°C constant temperature water bath under nitrogen protection for 28 minutes; Step 2, grafting treatment: adding 20 parts by weight of 1,3-xylene trimethoxysilane and 0.6 parts of catalyst stannous octoate into the three-necked flask, controlling the dropping speed to be 1 drop / s, after the dropping is completed, increasing the temperature to 83°C, and keeping stirring for 4.5 hours to obtain modified material; Step 3, purification treatment: distilling the modified material in a vacuum state for 1 hour, controlling the distillation temperature to be 73°C, and the distillation time to be 1.2 hours to obtain purified modified crude product; Step 4, neutralization and stabilization: adding glacial acetic acid to the purified modified crude product to adjust the pH to 5, stirring for 15 minutes, and diluting and stirring with anhydrous ethanol to obtain stable modified silane coupling agent.

[0023] A preparation method of a high-temperature-resistant sealing agent, for preparing the high-temperature-resistant sealing agent as described above, taking acid nano-silica sol, cosolvent, hydrolysis inhibitor, silane coupling agent A, silane coupling agent B, and wetting agent by weight parts, mixing, stirring and standing. Among them, the high-temperature-resistant sealing agent in the embodiment of the application is not yellow, decomposed and peeled off based on 2 hours of baking in an oven at 250°C. At the same time, the high-temperature-resistant sealing agent is not corroded based on 1000 hours of salt spray corrosion. Embodiment

[0024] A high-temperature-resistant sealing agent, comprising 30 parts by weight of an acidic nanosilica sol, 60 parts by weight of isopropyl alcohol, 10 parts by weight of 1,2-propanediol, 10 parts by weight of 3-(2,3-epoxypropoxy)propyl trimethoxysilane, 6 parts by weight of phenyl-modified γ-aminopropyl triethoxysilane, and 0.01 part by weight of wetting agent Lutensol TO5. The acidic nanosilica sol comprises 25% by mass of silicon dioxide with a particle size less than 20 nm, and the pH of the acidic nanosilica sol is 3.

[0025] The preparation method of the phenyl-modified γ-aminopropyl triethoxysilane comprises the following steps: Step 1, pretreatment: 100 parts by weight of γ-aminopropyl triethoxysilane is placed in a three-necked flask, and stirred in a 50°C constant-temperature water bath under nitrogen protection for 30 minutes; Step 2, grafting treatment: 22 parts by weight of 1,3-ditolyl trimethoxysilane and 0.7 parts by weight of catalyst stannous octoate are added dropwise into the three-necked flask, the dropwise speed is controlled at 1 drop / s, after the dropwise addition is completed, the temperature is raised to 85°C, and the modified material is obtained after stirring for 4.5 hours; Step 3, purification treatment: the modified material is distilled under vacuum for 1.1 hours, the distillation temperature is controlled at 75°C, and the distillation time is 1.2 hours, to obtain a purified modified crude product; Step 4, neutralization and stabilization: add glacial acetic acid to the purified modified crude product to adjust the pH to 5.5, stir for 15 minutes, and dilute and stir with anhydrous ethanol to obtain a stable modified silane coupling agent.

[0026] A preparation method of a high-temperature-resistant sealing agent, for preparing the high-temperature-resistant sealing agent as described above, the acidic nanosilica sol, the cosolvent, the hydrolysis inhibitor, the silane coupling agent A, the silane coupling agent B, and the wetting agent are mixed and stirred and then left to stand. The high-temperature-resistant sealing agent obtained in Example 2 of the present application is not yellowed, decomposed, or peeled off after being treated in an oven at 250°C for 2 hours. At the same time, the high-temperature-resistant sealing agent is not corroded after being subjected to salt spray corrosion for 1000 hours. Example

[0027] A high-temperature-resistant sealing agent, comprising 32 parts by weight of an acidic nanosilica sol, 65 parts by weight of isopropyl alcohol, 12 parts by weight of 1,2-propanediol, 12 parts by weight of 3-(2,3-epoxypropoxy)propyl trimethoxysilane, 6.8 parts by weight of phenyl-modified γ-aminopropyl triethoxysilane, and 0.015 parts by weight of wetting agent Lutensol TO5. The acidic nanosilica sol comprises 25% by mass of silicon dioxide with a particle size less than 20 nm, and the pH of the acidic nanosilica sol is 3.

[0028] The preparation method of the phenyl-modified γ-aminopropyl triethoxysilane comprises the following steps: Step 1, pretreatment: take 110 parts by weight of γ-aminopropyl triethoxysilane into a three-necked flask, and stir in a 52℃ constant temperature water bath under nitrogen protection for 32 minutes; Step 2, grafting treatment: add 25 parts by weight of 1,3-dimethylphenyl trimethoxysilane and 0.9 parts by weight of catalyst stannous octoate into the three-necked flask, control the dropping speed to be 1 drop / s, after the dropping is completed, increase the temperature to 87℃, and keep stirring for 4.5 hours to obtain the modified material; Step 3, purification treatment: distill the modified material under vacuum for 1.2 hours, control the distillation temperature to be 77℃, and the distillation time to be 1.3 hours to obtain the purified modified crude product; Step 4, neutralization and stabilization: add glacial acetic acid to the purified modified crude product to adjust the pH to 6, stir for 15 minutes, and dilute and stir with anhydrous ethanol to obtain the stable modified silane coupling agent.

[0029] A preparation method of a high-temperature-resistant sealing agent, for preparing the high-temperature-resistant sealing agent as described above, acid nano-silica sol, cosolvent, hydrolysis inhibitor, silane coupling agent A, silane coupling agent B, and wetting agent are mixed and stirred and then left to stand. In the high-temperature-resistant sealing agent in the embodiments of the present application, no yellowing, decomposition, and peeling occur after 2 hours of baking in an oven at 250℃. At the same time, the high-temperature-resistant sealing agent does not corrode after 1000 hours of salt spray corrosion.

[0030] It should be noted that the high-temperature resistance test in the embodiments of the present application is to coat the sealing agent in the corresponding example or comparative example on a galvanized test piece, put it into an oven at 250℃ for 2 hours, and then observe whether the sealing agent coating layer is yellow, decomposed, or peeled off.

[0031] The salt spray resistance test in the embodiments of the present application is to test the salt spray resistance of the galvanized test piece coated with the sealing agent in the corresponding example or comparative example according to the standard salt spray test method. The result shows whether obvious corrosion occurs on the surface of the test piece after 1000 hours of salt spray corrosion.

[0032] Comparative Example 1 The difference between Comparative Example 1 and Example 2 is that the high-temperature-resistant sealing agent in Comparative Example 1 does not contain silane coupling agent B.

[0033] In the high-temperature-resistant sealing agent in Comparative Example 1 of the present application, slight decomposition and peeling occur after 2 hours of baking in an oven at 250℃. At the same time, the high-temperature-resistant sealing agent is found to be partially corroded after 1000 hours of salt spray corrosion.

[0034] Comparative Example 2 The difference between Comparative Example Two and Example Two is that the high-temperature resistant sealant in Comparative Example Two does not add a hydrolysis inhibitor.

[0035] The high-temperature resistant sealant in Comparative Example Two of the present application is tested to produce slight yellowing based on a 2-hour treatment of baking in an oven at 250°C. At the same time, the high-temperature resistant sealant is found to have small local corrosion after 1000 hours of salt spray corrosion.

[0036] Comparative Example Three The difference between Comparative Example Three and Example Two is that the silane coupling agent B in the high-temperature resistant sealant in Comparative Example Three is γ-aminopropyl triethoxysilane.

[0037] The high-temperature resistant sealant in Comparative Example Three of the present application is tested to produce slight yellowing based on a 2-hour treatment of baking in an oven at 250°C. At the same time, the high-temperature resistant sealant does not corrode based on 1000 hours of salt spray corrosion.

[0038] In summary, the present application provides a high-temperature resistant sealant and a preparation method thereof, which has the effect of resisting high-temperature environment, does not yellow or decompose at high temperature, maintains good sealing performance, protects the surface of the treated material, and at the same time has good water solubility, stability and low cost, thereby meeting the needs of different industrial fields for high-temperature resistant sealants.

[0039] The "first", "second", "third", "fourth" and the like (if any) referred to herein are used for distinguishing between similar objects, and are not necessarily intended to refer to a particular order or sequence among the objects. It is understood that the data used herein can be interchanged, where appropriate, so that the embodiments described herein can be carried out in sequences other than those described herein. Furthermore, use of the terms "including", "containing", "comprising", "having" and variations thereof herein is intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises, has, includes or contains a list of steps or elements, but not those specifically listed or any other steps or elements not expressly included in the process, method, article, or apparatus, is still within the scope of the present application.

[0040] It should be noted that the description involving "first", "second" and the like in the present application is only for descriptive purposes, and cannot be understood as indicating or implying the relative importance of the technical features indicated, or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second" can explicitly or implicitly include at least one of the features. In addition, the technical solutions of various embodiments can be combined with each other, but must be based on the realization of ordinary skilled in the art, when the combination of technical solutions contradicts each other or cannot be realized, it should be considered that the combination of technical solutions does not exist, nor within the scope of protection claimed in the present application.

[0041] The principles and implementation manners of the present application are described by using specific examples in the present application, and the above examples are only used to help understand the method and its core idea of the present application; meanwhile, for the general technical personnel in the art, the specific implementation manners and application ranges will be changed according to the idea of the present application, and the above description should not be understood as the limitation of the present application.

Claims

1. A high-temperature resistant sealant, characterized in that, It includes 25-32 parts by weight of acidic nano-silica sol, 56-65 parts of co-solvent, 8-12 parts of hydrolysis inhibitor, 9-12 parts of silane coupling agent A, 5.5-6.8 parts of silane coupling agent B, and 0.01-0.015 parts of wetting agent; wherein the silane coupling agent B is phenyl-modified γ-aminopropyltriethoxysilane.

2. The high-temperature resistant sealant according to claim 1, characterized in that: The acidic nano-silica sol comprises 25% silica by mass, and the silica has a particle size of less than 20 nm.

3. The high-temperature resistant sealant according to claim 2, characterized in that: The pH of the acidic nano-silica sol is 3.

4. The high-temperature resistant sealant according to claim 1, characterized in that: The cosolvent is isopropanol, the hydrolysis inhibitor is 1,2-propanediol, and the silane coupling agent A is 3-(2,3-epoxypropoxy)propyltrimethoxysilane.

5. The high-temperature resistant sealant according to claim 1, characterized in that: The wetting agent is a C13-carbonyl alcohol ethoxylate, and the C13-carbonyl alcohol ethoxylate is Lutensol TO5, a wetting agent purchased from BASF.

6. A method for preparing a high-temperature resistant sealant, used to prepare the high-temperature resistant sealant as described in any one of claims 1-5, characterized in that: Take the acidic nano silica sol, cosolvent, hydrolysis inhibitor, silane coupling agent A, silane coupling agent B and wetting agent according to the weight parts, mix them, stir and let stand.

7. The method for preparing a high-temperature resistant sealant according to claim 6, characterized in that: The high-temperature resistant sealant does not yellow, decompose, or peel off after being baked in an oven at 250°C for 2 hours.

8. The method for preparing a high-temperature resistant sealant according to claim 6, characterized in that: The high-temperature resistant sealant is based on its resistance to salt spray corrosion after 1000 hours.

9. The method for preparing a high-temperature resistant sealant according to claim 1, characterized in that, The preparation method of the phenyl-modified γ-aminopropyltriethoxysilane includes the following steps: Step 1, Pretreatment: Take 90-110 parts by weight of γ-aminopropyltriethoxysilane and place it in a three-necked flask. Stir in a constant temperature water bath at 50±2℃ for 28-32 minutes under nitrogen protection. Step 2, Grafting treatment: 20-25 parts by weight of 1,3-dimethyltrimethoxysilane and 0.6-0.9 parts by weight of stannous octoate catalyst are added dropwise to a three-necked flask, with the dropping rate controlled at 1 drop / s. After the addition is completed, the temperature is raised to 83-87℃ and stirred for 4.5 hours to obtain the modified material. Step 3: Purification: Distill the modified material under vacuum for 1-1.2 hours, controlling the distillation temperature at 73-77℃ and the distillation time at 1.2-1.3 hours, to obtain the purified modified crude product. Step 4, Neutralization and Stabilization: Add glacial acetic acid to the purified and modified crude product to adjust the pH to 5-6, stir for 15 minutes, dilute with anhydrous ethanol and stir to obtain a stable modified silane coupling agent.