Aqueous high temperature resistant silicone resin coating and method for its preparation

Abstract

This invention provides a water-based high-temperature resistant silicone resin coating and its preparation method, comprising the following components in parts by weight: 35-60 parts of hydrophilic modified silicone resin, 5-15 parts of epoxy-modified silica sol, 1-3 parts of emulsifier, 1-6 parts of amino-terminated hyperbranched polyamide, 3-6 parts of additives, and 40-60 parts of water; wherein the hydrophilic modified silicone resin is obtained by reacting amino silicone oil, trifunctional epoxy resin, octaaminoPOSS, and epoxy polyether. The trifunctional epoxy resin is triglycidyl-p-aminophenol. This invention not only improves the hydrophilicity of organosilicon resin but also optimizes the compatibility between various components, effectively improving the stability, high-temperature resistance, and strength of the coating, solving the problems existing in the prior art, and has good application prospects.

Description

Technical Field

[0001] This invention relates to the field of coating technology, specifically to a water-based high-temperature resistant silicone resin coating and its preparation method. Background Technology

[0002] Organosilicon resins have been widely used in coatings, becoming a key component of high-performance coatings due to their excellent weather resistance, heat resistance, and chemical stability. Their Si-O bond structure endows coatings with outstanding thermal stability, with a heat resistance temperature up to 250℃, and also provides good UV resistance, making them suitable for harsh environments such as aerospace, automotive, and building exteriors. Blending organosilicon resins with acrylic resins, epoxy resins, etc., can further enhance the flexibility, abrasion resistance, and stain resistance of coatings, further expanding the applications of organosilicon resins. Environmentally friendly water-based organosilicon resins, with their high performance and sustainability advantages, are more in line with the modern trend of green coating development and represent the future direction of this field.

[0003] However, existing silicone resin-based coatings still have some shortcomings. For example, when the temperature reaches 300-400℃ or higher, the silicone resin decomposes, compromising the protective effect of the coating. To improve the high-temperature resistance of the coating, heat-resistant fillers, such as silica sol and metal oxides, are usually added. However, inorganic fillers have poor compatibility with organic resins, making it difficult for composite coatings to achieve ideal high-temperature resistance. Furthermore, uneven distribution can lead to a decrease in adhesion, toughness, and weather resistance. Additionally, conventional epoxy resins compounded with silicone resins have poor heat resistance, making it difficult to guarantee the reliability of the coating under high-temperature conditions. Therefore, further optimization of the overall performance of waterborne silicone resin coatings is a current research focus in this field.

[0004] In conclusion, there is an urgent need to develop a new technical solution to address the shortcomings of existing technologies. Summary of the Invention

[0005] The water-based high-temperature resistant silicone resin coating provided by this invention is formulated with hydrophilic modified silicone resin, epoxy-based silica sol and other substances. It not only improves the hydrophilicity of the silicone resin, but also optimizes the compatibility between the components, effectively improving the stability, high-temperature resistance and strength of the coating, solving the problems existing in the prior art, and has good application prospects.

[0006] One object of the present invention is to provide a water-based high-temperature resistant silicone resin coating, wherein the water-based high-temperature resistant silicone resin coating comprises the following components in parts by weight:

[0007]

[0008]

[0009] in,

[0010] The hydrophilic modified silicone resin is obtained by reacting amino silicone oil, trifunctional epoxy resin, octaaminoPOSS (cage-type polysilsesquioxane), and epoxy polyether.

[0011] Furthermore, the trifunctional epoxy resin is triglycidyl-p-aminophenol.

[0012] Furthermore, the epoxy polyether is polyethylene glycol diglycidyl ether.

[0013] Furthermore, the epoxy-based silica sol is an epoxy-based silane coupling agent oligomer or tetraethyl orthosilicate modified silica sol.

[0014] Furthermore, the average particle size of the silica sol is ≤0.2μm.

[0015] Furthermore, the terminal amino hyperbranched polyamide is selected from one or more of HyPer N101, HyPer N102, and HyPer N103.

[0016] Furthermore, the preparation method of the water-based high-temperature resistant silicone resin coating includes the following steps:

[0017] S1. Mix amino silicone oil and trifunctional epoxy resin, heat and react to obtain intermediate product;

[0018] S2. The intermediate product and octaaminoPOSS are mixed, heated and reacted, and then epoxy polyether is added and the reaction is continued to obtain hydrophilic modified silicone resin.

[0019] S3. Mix water, hydrophilic modified silicone resin, and epoxy-based silica sol, then add emulsifier, stir, add terminal amino hyperbranched polyamide and additives, and discharge to obtain the water-based high-temperature resistant silicone resin coating.

[0020] Furthermore, in step S1, the temperature of the heating reaction is 140-150°C.

[0021] Furthermore, in step S2, the temperature of the heating reaction is 40-90°C.

[0022] The present invention has the following beneficial effects:

[0023] (1) The waterborne high-temperature resistant silicone resin coating of the present invention contains a hydrophilic modified silicone resin. This component first reacts with amino silicone oil and trifunctional epoxy resin to introduce a large number of epoxy groups, then reacts the epoxy groups with octaamino POSS, and finally reacts with amino groups and epoxy polyethers to obtain the product. The hydrophilic modified silicone resin contains hydrophilic polyethylene glycol segments, which effectively improves the hydrophilicity of the resin and improves the stability of the coating emulsion. More importantly, the introduction of POSS particles into the modified silicone resin can significantly improve the heat resistance, high temperature resistance, and mechanical strength of the resin. In addition, the present invention uses trifunctional epoxy resin to react with silicone oil. This resin has the characteristics of high temperature resistance and high strength, and can crosslink silicone oil to form a network structure. After the introduced epoxy groups further react with substances such as octaamino POSS, the final product has a stable and dense three-dimensional crosslinked structure, which improves the thermal stability and also enhances the mechanical properties such as toughness and strength. The large number of active functional groups in the modified resin also greatly promote the adhesion of the coating.

[0024] (2) The present invention also modifies the surface of silica sol by using epoxy silane coupling agent oligomer and tetraethyl orthosilicate. On the one hand, it improves the compatibility between silica sol particles and organic resin, and can be more stable and uniformly dispersed in emulsion. On the other hand, the functional group density of silane coupling agent oligomer is greater, so that the surface of modified silica sol particles has more epoxy groups, and thus can be more fully crosslinked with components such as organosilicon resin and amino-terminated polyamide, so that silica sol particles are embedded in polymer network. Through the synergistic effect of organic and inorganic components, the comprehensive performance of coating is enhanced. Detailed Implementation

[0025] To more clearly illustrate the technical solution of the present invention, the following embodiments are provided. Unless otherwise stated, the raw materials, reactions, and post-processing methods appearing in the embodiments are all commercially available raw materials and technical methods well known to those skilled in the art.

[0026] The terms "preferred," "more preferably," and "more suitable" used in this invention refer to embodiments of the invention that provide certain beneficial effects under certain circumstances. However, other embodiments may also be preferred under the same or other circumstances. Furthermore, the description of one or more preferred embodiments does not imply that other embodiments are unavailable, nor is it intended to exclude other embodiments from the scope of this invention.

[0027] It should be understood that, except in any operational instance or otherwise indicated, the amounts or all figures representing ingredients used, for example, in the specification and claims, should be understood to be modified by the term "about" in all cases. Therefore, unless otherwise stated, the numerical parameters set forth in the following specification and appended claims are approximate values ​​varying according to the desired performance to be obtained according to the invention.

[0028] In the embodiments of the present invention, the emulsifier is WL-92 emulsifier (purchased from Xinyi Synthetic Technology Co., Ltd.) and OP-10 (purchased from Aladdin) in a mass ratio of 4:1; the additives are defoamer BYK-A530, cosolvent tripropylene glycol butyl ether, dispersant BYK-190 and accelerator N-(2-hydroxy-4-nitrobenzene)-N',N'-dimethylurea in a mass ratio of 0.5:2.5:1:1.

[0029] The amino-terminated hyperbranched polyamide used in this embodiment of the invention was purchased from Wuhan Hyperbranched Resin Technology Co., Ltd., N102.

[0030] The preparation method of the epoxy-based silica sol in this embodiment of the invention includes the following steps:

[0031] A mixture of silica sol (purchased from Shandong Baite New Materials, LS100), tetraethyl orthosilicate, and epoxy silane coupling agent oligomer (purchased from Guangzhou Longkai Chemical, LK-560) in a mass ratio of 5:1:1 was stirred at 70°C for 5 hours, filtered, and dried to obtain epoxy-oxidized silica sol.

[0032] The octaaminoPOSS used in this embodiment of the invention was purchased from Xi'an Qiyue Biotechnology Co., Ltd., CAS No. 150380-11-3.

[0033] The amino silicone oil used in this embodiment of the invention is Dow Corning OFX-8040A.

[0034] The polyethylene glycol diglycidyl ether used in this embodiment of the invention was purchased from Aladdin, with Mn≈1000.

[0035] In the embodiments of this invention, "parts" refers to parts by mass.

[0036] Example 1

[0037] A water-based high-temperature resistant silicone resin coating, wherein the water-based high-temperature resistant silicone resin coating comprises the following components in parts by weight:

[0038]

[0039]

[0040] The preparation method of the water-based high-temperature resistant silicone resin coating includes the following steps:

[0041] S1. Using acetone as a solvent, amino silicone oil and triglycidyl-p-aminophenol in a mass ratio of 2:1 were mixed and reacted at 140°C for 3 hours to obtain an intermediate product.

[0042] S2. Add octaaminoPOSS to the intermediate product and react at 75°C for 3 hours. Then add polyethylene glycol diglycidyl ether and react at 50°C for 6 hours under a nitrogen atmosphere. After removing the solvent and drying, the hydrophilic modified silicone resin is obtained.

[0043] The mass ratio of triglycidyl-p-aminophenol, octaaminoPOSS, and polyethylene glycol diglycidyl ether is 1:1.1:0.3.

[0044] S3. Mix water, hydrophilic modified silicone resin, and epoxy-based silica sol according to the above-mentioned mass proportions, then add emulsifier, stir, add terminal amino hyperbranched polyamide and additives, and discharge to obtain the water-based high-temperature resistant silicone resin coating.

[0045] Example 2

[0046] A water-based high-temperature resistant silicone resin coating, wherein the water-based high-temperature resistant silicone resin coating comprises the following components in parts by weight:

[0047]

[0048] The preparation method of the water-based high-temperature resistant silicone resin coating includes the following steps:

[0049] S1. Using acetone as a solvent, amino silicone oil and triglycidyl-p-aminophenol in a mass ratio of 2:1 were mixed and reacted at 140°C for 3 hours to obtain an intermediate product.

[0050] S2. Add octaaminoPOSS to the intermediate product and react at 75°C for 3 hours. Then add polyethylene glycol diglycidyl ether and react at 50°C for 6 hours under a nitrogen atmosphere. After removing the solvent and drying, the hydrophilic modified silicone resin is obtained.

[0051] The mass ratio of triglycidyl-p-aminophenol, octaaminoPOSS, and polyethylene glycol diglycidyl ether is 1:1.1:0.3.

[0052] S3. Mix water, hydrophilic modified silicone resin, and epoxy-based silica sol according to the above-mentioned mass proportions, then add emulsifier, stir, add terminal amino hyperbranched polyamide and additives, and discharge to obtain the water-based high-temperature resistant silicone resin coating.

[0053] Example 3

[0054] A water-based high-temperature resistant silicone resin coating, wherein the water-based high-temperature resistant silicone resin coating comprises the following components in parts by weight:

[0055]

[0056] The preparation method of the water-based high-temperature resistant silicone resin coating includes the following steps:

[0057] S1. Using acetone as a solvent, amino silicone oil and triglycidyl-p-aminophenol in a mass ratio of 2:1 were mixed and reacted at 140°C for 3 hours to obtain an intermediate product.

[0058] S2. Add octaaminoPOSS to the intermediate product and react at 75°C for 3 hours. Then add polyethylene glycol diglycidyl ether and react at 50°C for 6 hours under a nitrogen atmosphere. After removing the solvent and drying, the hydrophilic modified silicone resin is obtained.

[0059] The mass ratio of triglycidyl-p-aminophenol, octaaminoPOSS, and polyethylene glycol diglycidyl ether is 1:1.1:0.3.

[0060] S3. Mix water, hydrophilic modified silicone resin, and epoxy-based silica sol according to the above-mentioned mass proportions, then add emulsifier, stir, add terminal amino hyperbranched polyamide and additives, and discharge to obtain the water-based high-temperature resistant silicone resin coating.

[0061] Comparative Example 1

[0062] A silicone resin coating, the difference between this comparative example and Example 1 is that steps S1 and S2 are modified as follows: amino silicone oil and polyethylene glycol diglycidyl ether are mixed in a mass ratio of 2:0.5 and reacted at 50°C for 6 hours under a nitrogen atmosphere to obtain a hydrophilic modified silicone resin; other components and preparation methods are the same as in Example 1.

[0063] Comparative Example 2

[0064] A silicone resin coating, the difference between this comparative example and Example 1 is that steps S1 and S2 are deleted, the hydrophilic modified silicone resin is replaced with a mixture of amino silicone oil, E12 epoxy resin and octaaminoPOSS in a mass ratio of 2:1:1; and in the preparation method of epoxy-oxidized silica sol, the epoxy-oxidized silane coupling agent oligomer and tetraethyl orthosilicate are replaced with epoxy-oxidized silane coupling agent KH-560; other components and preparation methods are the same as in Example 1.

[0065] Test case

[0066] Test method:

[0067] Stability: The samples prepared in Examples 1-3 and Comparative Examples 1-2 were sealed in transparent containers and placed at a constant temperature of 40°C for 60 days. After being taken out and allowed to return to room temperature, the morphology of the samples was observed: no obvious precipitation or layering was considered qualified, and obvious precipitation or layering was considered unqualified.

[0068] Adhesion, impact strength, impermeability, and heat resistance (300℃, 6h): tested according to GB / T 9286-1998, GB / T1732-1993, GB / T 16777-2008, and GB / T 1735-1979 standards.

[0069] The test results are shown in Table 1.

[0070] Table 1. Performance test results of samples from Examples 1-3 and Comparative Examples 1-2

[0071]

[0072] Based on the above experimental data, it can be concluded that the waterborne high-temperature resistant silicone resin coating prepared in the embodiments of the present invention exhibits good long-term storage stability, strong adhesion, high impact strength, and strong high-temperature resistance, demonstrating excellent comprehensive performance. In contrast, Comparative Examples 1-2, due to the replacement of the hydrophilic modified silicone resin and epoxy-modified silica sol, resulted in the resin failing to form a stable network cross-linked structure and lacking thermally stable and high-temperature resistant groups. Consequently, their mechanical properties and high-temperature resistance were significantly reduced. Furthermore, the reduced number of active groups also led to a significant decrease in the adhesion of Comparative Examples 1 and 2. In summary, the waterborne high-temperature resistant silicone resin coating of the present invention solves the problems and defects existing in the prior art and is of great significance to the development and progress of organosilicon resin coating products.

[0073] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0074] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A water-based high-temperature resistant silicone resin coating, characterized in that, The water-based high-temperature resistant silicone resin coating comprises the following components in parts by weight: 35-60 parts of hydrophilic modified silicone resin 5-15 parts of epoxy-based silica sol 1-3 parts emulsifier 1-6 parts of amino-terminated hyperbranched polyamide 3-6 parts of auxiliary agent 40-60 parts water; in, The hydrophilic modified silicone resin is obtained by reacting amino silicone oil, trifunctional epoxy resin, octaaminoPOSS and epoxy polyether. The trifunctional epoxy resin is triglycidyl-p-aminophenol; The epoxy polyether is polyethylene glycol diglycidyl ether; The preparation method of the hydrophilic modified silicone resin includes the following steps: S1. Mix amino silicone oil and trifunctional epoxy resin, heat and react to obtain intermediate product; S2. The intermediate product and octaaminoPOSS are mixed, heated and reacted, and then epoxy polyether is added and the reaction is continued to obtain hydrophilic modified silicone resin.

2. The water-based high-temperature resistant silicone resin coating according to claim 1, characterized in that, The epoxy-based silica sol is an epoxy-based silane coupling agent oligomer or tetraethyl orthosilicate modified silica sol.

3. The water-based high-temperature resistant silicone resin coating according to claim 1, characterized in that, The terminal amino hyperbranched polyamide is selected from one or more of HyPer N101, HyPer N102, and HyPer N103.

4. The water-based high-temperature resistant silicone resin coating according to claim 1, characterized in that, The preparation method of the water-based high-temperature resistant silicone resin coating includes the following steps: S1. Mix amino silicone oil and trifunctional epoxy resin, heat and react to obtain intermediate product; S2. The intermediate product and octaaminoPOSS are mixed, heated and reacted, and then epoxy polyether is added and the reaction is continued to obtain hydrophilic modified silicone resin. S3. Mix water, hydrophilic modified silicone resin, and epoxy-modified silica sol, then add emulsifier, stir, add terminal amino hyperbranched polyamide and additives, and discharge to obtain the water-based high-temperature resistant silicone resin coating.

5. The water-based high-temperature resistant silicone resin coating according to claim 4, characterized in that, In step S1, the temperature of the heating reaction is 140-150℃.

6. The water-based high-temperature resistant silicone resin coating according to claim 4, characterized in that, In step S2, the temperature of the heating reaction is 40-90℃.

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