Water-based organic silicon coating as well as preparation method and application thereof

Abstract

The invention discloses a water-based organic silicon coating as well as a preparation method and application thereof. The water-based organic silicon coating is prepared from 100 parts of water-based vinyl silicone resin, 3 to 20 parts of water-based hydrogen-containing silicone resin, 3 to 20 parts of water-based catalyst, 5 to 20 parts of filler, 3 to 10 parts of wax emulsion and 50 to 200 parts of water-based solvent. A coating layer formed by the water-based organic silicon coating has smoothness, wear resistance, toughness, excellent touch feeling and high environmental protection property, and can be applied to the surfaces of flexible substrates in the fields of 3C digital products, automotive interiors and intelligent wearing; the raw materials are easy to obtain, the preparation process is simple, the requirement on production equipment is low, and the method is suitable for large-scale industrial production.

Description

Technical Field

[0001] The present invention relates to the technical field of organosilicon coatings, and in particular to a water-based organosilicon coating having a soft and tough coating, a silky and delicate touch, and skin-friendly feel, as well as a preparation method and application thereof. Background Art

[0002] Silicone coatings are a type of coating with low surface energy and low polarity, and have excellent chemical stability. Traditional silicone coatings are widely used in the fields of corrosion protection and building protection, but are less used in 3C digital products, automotive interiors, and smart wearables.

[0003] At present, the patents related to silicone coatings reported at home and abroad often have many problems such as uneven coating, poor touch, and substandard environmental performance. For example, CN115260903A discloses a silicone coating for flexible substrates such as silicone and TPU, but a large amount of organic solvents need to be added during use, and the high VOC is likely to have a certain impact on the environment; Patent CN117881755A discloses an aminosiloxane additive for water-based coatings. Although it can improve the flatness of the coating, the introduction of amino polarity will reduce the anti-fouling performance of the coating and cannot provide a soft and silky touch. Summary of the invention

[0004] The present invention provides a water-based organosilicon coating and a preparation method and application thereof, which are used to solve the technical problems of the existing organosilicon coating mentioned in the background technology.

[0005] In order to solve the above technical problems, the technical solution proposed by the present invention is: A water-based silicone coating comprising the following components in parts by weight: 100 parts of water-based vinyl silicone resin, 3-20 parts of water-based hydrogenated silicone resin, 3-20 parts of water-based catalyst, 5-20 parts of filler, 3-10 parts of wax emulsion and 50-200 parts of water-based solvent; The water-based vinyl silicone resin comprises silicone resin A and an emulsifier, wherein the main chain structure of silicone resin A is , a and b are the number of chain segments; the molecular weight of the silicone resin A is 50000-1000000 g / mol; the water-based hydrogenated silicone resin includes silicone resin B and silicone resin C, and the main chain structure of the silicone resin B is , m and n are the number of chain segments; silicone resin C is a hydrogen-containing MQ silicone resin with a structural formula of [(CH3)2HSiO 1 / 2 ] x [(CH3)3SiO 1 / 2 ] y [SiO 4 / 2 ] z .

[0006] The design idea of ​​the above technical solution is that the coating system adopts a water-based system, has no VOC emissions, is environmentally friendly, has no harmful substances added, and is harmless to the human body, so it can be used as a coating that contacts the skin. The water-based vinyl silicone resin and the water-based hydrogenated silicone resin in the system can undergo a cross-linking reaction under the catalysis of an aqueous catalyst. The cross-linking curing mechanism is a hydrosilylation reaction, which has a fast reaction speed and a thorough reaction, thereby forming a completely cross-linked flexible coating on the surface of the silicone material, and has good compatibility with the silicone substrate, and can be attached to the silicone substrate through intermolecular forces; the present invention adopts a high molecular weight water-based vinyl silicone resin, which can make the silicone coating have good flexibility and provide a self-lubricating property, so that the coating can have a very low friction coefficient, and at the same time, combined with the water-based hydrogenated MQ silicone resin, it can form a high cross-linking density enhanced coating and provide a smooth feel. In addition to the silicone resin system, the wax emulsion contains high-density polyethylene particles with an average particle size of less than 1 micron, which have good self-lubricating and wear-resistant properties. During the cross-linking and curing process of the coating, the polyethylene particles can float on the surface of the coating, thereby further improving the touch of the coating.

[0007] As a further preferred embodiment of the above technical solution, the mass of the vinyl group in the silicone resin A is 0.01% to 5% of the total mass of the silicone resin A.

[0008] As a further preferred embodiment of the above technical solution, the hydrogen mass content of the silicone resin B is 0.1% to 0.6%; the hydrogen mass content of the silicone resin B is 0.1% to 0.8%. By adding hydrogen-containing MQ silicone resin to silicone resin B, the coating can be further reinforced to improve the wear resistance of the coating.

[0009] As a further preferred embodiment of the above technical solution, the mass ratio of the silicone resin B to the silicone resin C is 1:(0.1-1.5).

[0010] As a further preferred embodiment of the above technical solution, the catalyst is a platinum catalyst with a platinum content of 50-10000 ppm.

[0011] As a further preferred embodiment of the above technical solution, the filler is a silica filler, and the particle size of the filler is 1-10 μm.

[0012] As a further preferred embodiment of the above technical solution, the particle size of the wax emulsion is 0.3-20 μm.

[0013] As a further preferred embodiment of the above technical solution, the emulsifier includes at least one of fatty alcohol polyoxyethylene ether, fatty acid polyoxyethylene ester, sorbitan fatty acid ester, alkylphenol polyoxyethylene ether, polyether silicone oil emulsifier and polyether emulsifier.

[0014] Based on the same technical concept, the present invention also provides a method for preparing the above-mentioned water-based silicone coating, comprising the following steps: S1, mixing the water-based vinyl silicone resin, the water-based hydrogenated silicone resin and the water-based catalyst to obtain a mixture A; S2, adding the filler into mixture A, and mixing to obtain mixture B; S3, adding the wax emulsion to mixture B, and mixing to obtain mixture C; S4, adding an aqueous solvent to the mixture C, and mixing them evenly to obtain the water-based silicone coating.

[0015] As a further preferred embodiment of the above technical solution, in S1, the mixing speed is 400-600 rpm, and the mixing time is 5-10 min; in S2, the mixing speed is 600-800 rpm, and the mixing time is 20-30 min; in S3, the mixing speed is 400-600 rpm, and the mixing time is 5-10 min; in S4, the mixing speed is 400-600 rpm, and the mixing time is 10-20 min.

[0016] Based on the same technical concept, the present invention also provides an application of the above-mentioned water-based silicone coating, which is used to form a coating on the surface of a flexible substrate.

[0017] As a further preferred embodiment of the above technical solution, the flexible substrate is a silicone substrate, a TPU substrate or a TPE substrate.

[0018] As a further preferred embodiment of the above technical solution, the curing time of the water-based silicone coating is 60 min to 90 min; and the curing temperature is 90° C. to 105° C.

[0019] As a further preferred embodiment of the above technical solution, the coating thickness of the water-based silicone coating on the surface of the flexible substrate is 11 to 23 μm.

[0020] As a further preferred embodiment of the above technical solution, the viscosity of the water-based silicone coating during construction is 20-30s (Zahn Cup 3#); the solid content of the water-based silicone coating during construction is 20%-30%.

[0021] The present invention has the following beneficial effects: (1) The water-based silicone coating of the present invention has a coating that is smooth, wear-resistant, tough, has a good touch and is highly environmentally friendly, and can be applied to the surface of flexible substrates in the fields of 3C digital products, automotive interiors, and smart wearables; (2) The water-based silicone coating of the present invention has readily available raw materials, a simple preparation process, and low requirements on production equipment, and is suitable for large-scale industrial production. DETAILED DESCRIPTION

[0022] The present invention is described in detail below in conjunction with the embodiments thereof, but the present invention can be implemented in many different ways as defined and covered by the claims.

[0023] The vinyl silicone resin A used in each embodiment of the present invention is a product of grade MY 273 produced by Anhui Mingyi Silicon Industry Co., Ltd., with a molecular weight of 72000 g / mol and a vinyl content of 0.09%; The hydrogen-containing silicone resin B used in each embodiment of the present invention is a product of grade MY 203 produced by Anhui Mingyi Silicon Industry Co., Ltd., and its hydrogen content is 0.75%; The silicone resin C used in each embodiment of the present invention is a product of brand DY-HMQ103 produced by Shandong Dayi Chemical Co., Ltd., and its hydrogen content is 0.4%; The catalyst D used in each embodiment of the present invention is a product of grade PC11 produced by Shanghai Neutron Star Chemical Technology Co., Ltd., and its platinum content is 2000ppm; The silica filler used in each embodiment of the present invention is a product of brand E-1011 produced by Tosoh SILICA Co., Ltd. of Japan, and its average particle size is 1.5 μm; The wax emulsion used in each embodiment of the present invention is an aqueous wax emulsion produced by Keim-Additec of Germany, with the brand name CT1088.

[0024] Embodiment 1: The water-based silicone coating of this embodiment includes the components in parts by weight shown in Table 1.

[0025] The water-based silicone coating of this embodiment is prepared by the following method: S1. Raw material preparation: 100 parts of vinyl silicone resin A and 8 parts of emulsifier fatty alcohol polyoxyethylene ether are mixed evenly in a stirrer, 100 parts of water are slowly added, and the mixture is fully mixed while being added. After the addition of water is completed, a homogenizer is used to perform homogenization treatment at 8000 rpm for 20 minutes to obtain a water-based vinyl silicone resin; 70 parts of hydrogenated silicone resin B and 30 parts of silicone resin C were mixed and fully dissolved, and then 8 parts of emulsifier fatty alcohol polyoxyethylene ether were added in a mixer and mixed evenly, and 100 parts of water were slowly added while being fully mixed. After the addition of water was completed, a homogenizer was used to homogenize for 20 minutes to obtain a water-based hydrogenated silicone resin.

[0026] 100 parts of catalyst D and 8 parts of emulsifier fatty alcohol polyoxyethylene ether were mixed evenly in a mixer, and 100 parts of water were slowly added while being fully mixed. After the addition of water was completed, a homogenizer was used to perform homogenization for 20 minutes to obtain a water-based catalyst.

[0027] S2, water-based vinyl silicone resin, water-based hydrogenated silicone resin, and water-based catalyst were added to a stirring tank and mixed at 500 rpm for 10 min to obtain a mixture A; S3, adding the silica filler to the mixture A under stirring at 500 rpm, increasing the speed to 700 rpm and stirring for 20 min to obtain a mixture B; S4, adding the wax emulsion to the mixture B, dispersing at 500 rpm for 10 min to obtain a mixture C; S5. Add deionized water to mixture D and disperse at 400 rpm for 20 min to obtain a water-based silicone coating.

[0028] The water-based silicone coating of this embodiment can form a coating on the surface of a flexible substrate, which specifically includes the following operations: spraying the prepared water-based silicone coating on the silicone material with a film thickness of 17 μm±2 μm, and baking at 100° C. for 90 minutes. Embodiment 2: The water-based silicone coating of this embodiment includes the components in parts by weight shown in Table 1.

[0029] The water-based silicone coating of this embodiment is prepared by the following method: S1. Raw material preparation: 100 parts of vinyl silicone resin A and 8 parts of emulsifier fatty alcohol polyoxyethylene ether are mixed evenly in a stirrer, 100 parts of water are slowly added, and the mixture is fully mixed while being added. After the addition of water is completed, a homogenizer is used to perform homogenization treatment at 8000 rpm for 20 minutes to obtain a water-based vinyl silicone resin; 70 parts of hydrogenated silicone resin B and 30 parts of silicone resin C were mixed and fully dissolved, and then 8 parts of emulsifier fatty alcohol polyoxyethylene ether were added in a mixer and mixed evenly, and 100 parts of water were slowly added while being fully mixed. After the addition of water was completed, a homogenizer was used to homogenize for 20 minutes to obtain a water-based hydrogenated silicone resin.

[0030] 100 parts of catalyst D and 8 parts of emulsifier fatty alcohol polyoxyethylene ether were mixed evenly in a mixer, and 100 parts of water were slowly added while being fully mixed. After the addition of water was completed, a homogenizer was used to perform homogenization for 20 minutes to obtain a water-based catalyst.

[0031] S2, water-based vinyl silicone resin, water-based hydrogenated silicone resin, and water-based catalyst were added to a stirring tank and mixed at 400 rpm for 8 min to obtain a mixture A; S3, adding the silica filler to the mixture A under stirring at 600 rpm, increasing the speed to 800 rpm and stirring for 20 min to obtain a mixture B; S4, adding the wax emulsion to the mixture B, dispersing at 400 rpm for 10 min to obtain a mixture C; S5. Add deionized water to mixture D and disperse at 600 rpm for 10 min to obtain a water-based silicone coating.

[0032] The water-based silicone coating of this embodiment can form a coating on the surface of a flexible substrate, which specifically includes the following operations: spraying the prepared water-based silicone coating on the silicone material with a film thickness of 17 μm±2 μm, and baking at 100° C. for 90 minutes. Embodiment 3: The water-based silicone coating of this embodiment includes the components in parts by weight shown in Table 1.

[0033] The water-based silicone coating of this embodiment is prepared by the following method: S1. Raw material preparation: 100 parts of vinyl silicone resin A and 8 parts of emulsifier fatty alcohol polyoxyethylene ether are mixed evenly in a stirrer, 100 parts of water are slowly added, and the mixture is fully mixed while being added. After the addition of water is completed, a homogenizer is used to perform homogenization treatment at 8000 rpm for 20 minutes to obtain a water-based vinyl silicone resin; 70 parts of hydrogenated silicone resin B and 30 parts of silicone resin C were mixed and fully dissolved, and then 8 parts of emulsifier fatty alcohol polyoxyethylene ether were added in a mixer and mixed evenly, and 100 parts of water were slowly added while being fully mixed. After the addition of water was completed, a homogenizer was used to homogenize for 20 minutes to obtain a water-based hydrogenated silicone resin.

[0034] 100 parts of catalyst D and 8 parts of emulsifier fatty alcohol polyoxyethylene ether were mixed evenly in a mixer, and 100 parts of water were slowly added while being fully mixed. After the addition of water was completed, a homogenizer was used to perform homogenization for 20 minutes to obtain a water-based catalyst.

[0035] S2, water-based vinyl silicone resin, water-based hydrogenated silicone resin, and water-based catalyst were added to a stirring tank and mixed at 600 rpm for 5 min to obtain a mixture A; S3, adding the silica filler to the mixture A under stirring at 400 rpm, increasing the speed to 600 rpm and stirring for 30 min to obtain a mixture B; S4, adding the wax emulsion to the mixture B, dispersing at 500 rpm for 10 min to obtain a mixture C; S5. Add deionized water to mixture D to obtain a water-based silicone coating.

[0036] The water-based silicone coating of this embodiment can form a coating on the surface of a flexible substrate, which specifically includes the following operations: spraying the prepared water-based silicone coating on the silicone material with a film thickness of 17 μm±2 μm, and baking at 100° C. for 90 minutes. Embodiment 4: The water-based silicone coating of this embodiment includes the components in parts by weight shown in Table 1.

[0037] The water-based silicone coating of this embodiment is prepared by the following method: S1. Raw material preparation: 100 parts of vinyl silicone resin A and 8 parts of emulsifier fatty alcohol polyoxyethylene ether are mixed evenly in a stirrer, 100 parts of water are slowly added, and the mixture is fully mixed while being added. After the addition of water is completed, a homogenizer is used to perform homogenization treatment at 8000 rpm for 20 minutes to obtain a water-based vinyl silicone resin; 70 parts of hydrogenated silicone resin B and 30 parts of silicone resin C were mixed and fully dissolved, and then 8 parts of emulsifier fatty alcohol polyoxyethylene ether were added in a mixer and mixed evenly, and 100 parts of water were slowly added while being fully mixed. After the addition of water was completed, a homogenizer was used to homogenize for 20 minutes to obtain a water-based hydrogenated silicone resin.

[0038] 100 parts of catalyst D and 8 parts of emulsifier fatty alcohol polyoxyethylene ether were mixed evenly in a mixer, and 100 parts of water were slowly added while being fully mixed. After the addition of water was completed, a homogenizer was used to perform homogenization for 20 minutes to obtain a water-based catalyst.

[0039] S2, water-based vinyl silicone resin, water-based hydrogenated silicone resin, and water-based catalyst were added to a stirring tank and mixed at 500 rpm for 10 min to obtain a mixture A; S3, adding the silica filler to the mixture A under stirring at 500 rpm, increasing the speed to 700 rpm and stirring for 20 min to obtain a mixture B; S4, adding the wax emulsion to the mixture B, dispersing at 500 rpm for 10 min to obtain a mixture C; S5. Add deionized water to mixture D to obtain a water-based silicone coating.

[0040] The water-based silicone coating of this embodiment can form a coating on the surface of a flexible substrate, which specifically includes the following operations: spraying the prepared water-based silicone coating on the silicone material with a film thickness of 17 μm±2 μm, and baking at 100° C. for 90 minutes. Embodiment 5: The water-based silicone coating of this embodiment includes the components in parts by weight shown in Table 1.

[0041] The water-based silicone coating of this embodiment is prepared by the following method: S1. Raw material preparation: 100 parts of vinyl silicone resin A and 8 parts of emulsifier fatty alcohol polyoxyethylene ether are mixed evenly in a stirrer, 100 parts of water are slowly added, and the mixture is fully mixed while being added. After the addition of water is completed, a homogenizer is used to perform homogenization treatment at 8000 rpm for 20 minutes to obtain a water-based vinyl silicone resin; 70 parts of hydrogenated silicone resin B and 30 parts of silicone resin C were mixed and fully dissolved, and then 8 parts of emulsifier fatty alcohol polyoxyethylene ether were added in a mixer and mixed evenly, and 100 parts of water were slowly added while being fully mixed. After the addition of water was completed, a homogenizer was used to homogenize for 20 minutes to obtain a water-based hydrogenated silicone resin.

[0042] 100 parts of catalyst D and 8 parts of emulsifier fatty alcohol polyoxyethylene ether were mixed evenly in a mixer, and 100 parts of water were slowly added while being fully mixed. After the addition of water was completed, a homogenizer was used to perform homogenization for 20 minutes to obtain a water-based catalyst.

[0043] S2, water-based vinyl silicone resin, water-based hydrogenated silicone resin, and water-based catalyst were added to a stirring tank and mixed at 500 rpm for 10 min to obtain a mixture A; S3, adding the silica filler to the mixture A under stirring at 500 rpm, increasing the speed to 700 rpm and stirring for 20 min to obtain a mixture B; S4, adding the wax emulsion to the mixture B, dispersing at 500 rpm for 10 min to obtain a mixture C; S5. Add deionized water to mixture D to obtain a water-based silicone coating.

[0044] The water-based silicone coating of this embodiment can form a coating on the surface of a flexible substrate, which specifically includes the following operations: spraying the prepared water-based silicone coating on the silicone material with a film thickness of 17 μm±2 μm, and baking at 100° C. for 90 minutes. Embodiment 6: The water-based silicone coating of this embodiment includes the components in parts by weight shown in Table 1.

[0045] The water-based silicone coating of this embodiment is prepared by the following method: S1. Raw material preparation: 100 parts of vinyl silicone resin A and 8 parts of emulsifier fatty alcohol polyoxyethylene ether are mixed evenly in a stirrer, 100 parts of water are slowly added, and the mixture is fully mixed while being added. After the addition of water is completed, a homogenizer is used to perform homogenization treatment at 8000 rpm for 20 minutes to obtain a water-based vinyl silicone resin; 70 parts of hydrogenated silicone resin B and 30 parts of silicone resin C were mixed and fully dissolved, and then 8 parts of emulsifier fatty alcohol polyoxyethylene ether were added in a mixer and mixed evenly, and 100 parts of water were slowly added while being fully mixed. After the addition of water was completed, a homogenizer was used to homogenize for 20 minutes to obtain a water-based hydrogenated silicone resin.

[0046] 100 parts of catalyst D and 8 parts of emulsifier fatty alcohol polyoxyethylene ether were mixed evenly in a mixer, and 100 parts of water were slowly added while being fully mixed. After the addition of water was completed, a homogenizer was used to perform homogenization for 20 minutes to obtain a water-based catalyst.

[0047] S2, water-based vinyl silicone resin, water-based hydrogenated silicone resin, and water-based catalyst were added to a stirring tank and mixed at 500 rpm for 10 min to obtain a mixture A; S3, adding the silica filler to the mixture A under stirring at 500 rpm, increasing the speed to 700 rpm and stirring for 20 min to obtain a mixture B; S4, adding the wax emulsion to the mixture B, dispersing at 500 rpm for 10 min to obtain a mixture C; S5. Add deionized water to mixture D to obtain a water-based silicone coating.

[0048] The water-based silicone coating of this embodiment can form a coating on the surface of a flexible substrate, which specifically includes the following operations: spraying the prepared water-based silicone coating on the silicone material with a film thickness of 17 μm±2 μm, and baking at 100° C. for 90 minutes. Embodiment 7: The water-based silicone coating of this embodiment includes the components in parts by weight shown in Table 1.

[0049] The water-based silicone coating of this embodiment is prepared by the following method: S1. Raw material preparation: 100 parts of vinyl silicone resin A and 8 parts of emulsifier fatty alcohol polyoxyethylene ether are mixed evenly in a stirrer, 100 parts of water are slowly added, and the mixture is fully mixed while being added. After the addition of water is completed, a homogenizer is used to perform homogenization treatment at 8000 rpm for 20 minutes to obtain a water-based vinyl silicone resin; 50 parts of hydrogenated silicone resin B and 50 parts of silicone resin C were mixed and fully dissolved, and then 8 parts of emulsifier fatty alcohol polyoxyethylene ether were added in a mixer and mixed evenly, and 100 parts of water were slowly added while being fully mixed. After the addition of water was completed, a homogenizer was used to homogenize for 20 minutes to obtain a water-based hydrogenated silicone resin.

[0050] 100 parts of catalyst D and 8 parts of emulsifier fatty alcohol polyoxyethylene ether were mixed evenly in a mixer, and 100 parts of water were slowly added while being fully mixed. After the addition of water was completed, a homogenizer was used to perform homogenization for 20 minutes to obtain a water-based catalyst.

[0051] S2, water-based vinyl silicone resin, water-based hydrogenated silicone resin, and water-based catalyst were added to a stirring tank and mixed at 500 rpm for 10 min to obtain a mixture A; S3, adding the silica filler to the mixture A under stirring at 500 rpm, increasing the speed to 700 rpm and stirring for 20 min to obtain a mixture B; S4, adding the wax emulsion to the mixture B, dispersing at 500 rpm for 10 min to obtain a mixture C; S5. Add deionized water to mixture D to obtain a water-based silicone coating.

[0052] The water-based silicone coating of this embodiment can form a coating on the surface of a flexible substrate, which specifically includes the following operations: spraying the prepared water-based silicone coating on the silicone material with a film thickness of 17 μm±2 μm, and baking at 100° C. for 90 minutes. Comparative Example 1: The difference between the organosilicon coating of this comparative example and Example 1 is that the molecular weight of the vinyl resin A of this comparative example is 11700 g / mol and the vinyl content is 0.05%. The composition ratio is shown in Table 1.

[0053] Comparative Example 2: The organosilicon coating of this comparative example is different from that of Example 1 only in that the platinum content of the catalyst D of this comparative example is 5000 ppm.

[0054] Table 1. Component ratio of waterborne silicone coatings in various examples

[0055] The performance test of the coating formed by the organic silicon coating of each embodiment and comparative example on the surface of the silica gel substrate is carried out, and the test method is as follows: The adhesion test is carried out according to GB9286-2021 standard.

[0056] Boiling test: Soak in boiling water (about 100℃) for 120 minutes, observe the coating surface condition and test the coating adhesion.

[0057] Abrasion test: Use Taber linear abrasion tester, rubber model CS-10, load 500 grams, 40 cycles / min for friction test.

[0058] Xenon lamp aging test: Select 420nm ultraviolet light with a light intensity of 0.80W / m2. If there is no obvious change on the coating surface after irradiation for a certain period of time, it is OK.

[0059] Bending test: Spray the organic silicone coating on the silicone material with a film thickness of 17μm~19μm, bend it 180°, and observe whether the product has cracks.

[0060] The friction coefficient is measured according to GB / T 10006-2021, with a load of 300 g and a traction speed of 100 mm / min.

[0061] The test results are shown in Table 2.

[0062] Table 2. Performance test results of the coatings formed in various embodiments and comparative examples

[0063] Combining Examples 1-7 and Comparative Examples 1 and 2 and Tables 1 and 2, it can be seen that the water-based silicone coating prepared by the present application has very good adhesion on the silicone material. This is because the cross-linking and curing mechanism of the water-based silicone coating used is a silane-hydrogen addition reaction, which has a fast reaction speed and a thorough reaction, thereby forming a completely cross-linked flexible coating on the surface of the silicone material, and has good compatibility with the silicone substrate, and can be attached to the silicone substrate through intermolecular forces. At the same time, the main chain of the water-based silicone resin contains a large number of methyl groups, which can greatly reduce the surface tension of the coating, making the coating have good hydrophobicity, and still has good adhesion after the high-temperature boiling test. Since the water-based silicone resin contains a large number of Si-O-Si bonds, and the molecular chain of the water-based vinyl silicone resin is relatively long, it can make the silicone coating have good flexibility and provide a self-lubricating property, so that the coating can have a very low friction coefficient, thereby providing a smooth feel. The polarity of the water-based silicone coating is very low and the bond energy of the Si-O-Si bond is high, so the coating has good anti-aging properties, and no yellowing occurs after 300 hours of xenon lamp aging test.

[0064] It can be seen from Examples 1-3 and Tables 1 and 2 that as the proportion of the water-based hydrogenated silicone resin in the formula increases, the friction coefficient of the coating decreases and the wear resistance is improved. This is because the water-based hydrogenated silicone resin contains a large number of silicon hydrogen groups that can react with the vinyl in the water-based vinyl silicone resin. As the number of silicon hydrogen groups increases, the reaction sites in the coating increase, thereby increasing the crosslinking density and strength of the coating, so that the coating has better wear resistance.

[0065] It can be seen from Examples 1, 4, and 5 and from Tables 1 and 2 that as the proportion of the water-based catalyst in the formula increases, the wear resistance of the coating is further improved. This is because the water-based catalyst contains platinum, which can efficiently catalyze the silane groups in the water-based hydrogenated silicone resin to undergo a silylation reaction with the vinyl groups in the water-based vinyl silicone resin. As the proportion of the catalyst increases, the rate of the silylation reaction is further improved, thereby deepening the degree of crosslinking of the coating and enhancing the wear resistance.

[0066] Combining Examples 1, 4, and 5 with Tables 1 and 2, it can be seen that the friction coefficient is further reduced after increasing the proportion of wax emulsion in the water-based organic coating. This is mainly because the wax emulsion used contains high-density polyethylene particles with an average particle size of less than 1 micron, which has good self-lubricating and wear-resistant properties. During the cross-linking and curing process of the coating, the polyethylene particles can float on the surface of the coating, thereby further improving the smoothness of the coating.

[0067] Combining Examples 1 and 7 with Tables 1 and 2, it can be seen that after increasing the proportion of silicone resin C in the water-based hydrogenated silicone resin, the friction coefficient of the coating is further reduced and the wear resistance is improved. This is because silicone resin C has a three-dimensional spherical structure, has good compatibility with other silicone resins, and contains silicon hydrogen groups that can be cross-linked with vinyl silicone resins, so silicone resin C can play a reinforcing role in the water-based organic silicone coating.

[0068] It can be seen from Example 1, Comparative Example 1 and Tables 1 and 2 that as the molecular weight of the vinyl silicone resin A in the water-based silicone coating formula increases, the wear resistance and toughness of the coating are further enhanced. This is because after the molecular weight increases, the free rotation and entanglement ability of the coating during the curing process is enhanced, making the molecular bonds closer.

[0069] It can be seen from Example 1, Comparative Example 2 and Tables 1 and 2 that as the platinum content of catalyst D in the water-based silicone coating increases, the wear resistance of the coating can be enhanced. This is because the cross-linking reaction rate of the coating is accelerated as the catalyst concentration increases, and it is ensured that all the resins in the water-based silicone coating are converted into cross-linked products.

[0070] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. For those skilled in the art, improvements and changes obtained without departing from the technical concept of the present invention should also be regarded as the protection scope of the present invention.

[0071] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A water-based silicone coating, characterized in that: The composition comprises the following components in parts by weight: 100 parts of water-based vinyl silicone resin, 3-20 parts of water-based hydrogenated silicone resin, 3-20 parts of water-based catalyst, 5-20 parts of filler, 3-10 parts of wax emulsion and 50-200 parts of water-based solvent; The water-based vinyl silicone resin comprises silicone resin A and an emulsifier, wherein the main chain structure of silicone resin A is , a and b are the number of chain segments; the molecular weight of the silicone resin A is 50000-1000000 g / mol; the water-based hydrogenated silicone resin includes silicone resin B and silicone resin C, and the main chain structure of the silicone resin B is , m and n are the number of chain segments; silicone resin C is a hydrogen-containing MQ silicone resin with a structural formula of [(CH3)2HSiO 1 / 2 ] x [(CH3)3SiO 1 / 2 ] y [SiO 4 / 2 ] z .

2. The water-based silicone coating according to claim 1, characterized in that: The mass of the vinyl group in the silicone resin A is 0.01% to 5% of the total mass of the silicone resin A.

3. The water-based silicone coating according to claim 1, characterized in that: The hydrogen mass content of the silicone resin B is 0.1% to 0.6%; the hydrogen mass content of the silicone resin B is 0.1% to 0.8%.

4. The water-based silicone coating according to claim 3, characterized in that: The mass ratio of the silicone resin B to the silicone resin C is 1:(0.1-1.5).

5. The water-based silicone coating according to any one of claims 1 to 4, characterized in that: The catalyst is a platinum catalyst, and the platinum content is 50-10000ppm.

6. The water-based silicone coating according to any one of claims 1 to 4, characterized in that: The filler is a silicon dioxide filler, and the particle size of the filler is 1-10 μm.

7. The water-based silicone coating according to any one of claims 1 to 4, characterized in that: The particle size of the wax emulsion is 0.3-20 μm.

8. A method for preparing the waterborne organosilicon coating according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1, mixing the water-based vinyl silicone resin, the water-based hydrogenated silicone resin and the water-based catalyst to obtain a mixture A; S2, adding the filler into mixture A, and mixing to obtain mixture B; S3, adding the wax emulsion to mixture B, and mixing to obtain mixture C; S4, adding an aqueous solvent to the mixture C, and mixing them evenly to obtain the water-based silicone coating.

9. The method for preparing a water-based organosilicon coating according to claim 8, characterized in that: In S1, the mixing speed is 400~600rpm, and the mixing time is 5~10min; in S2, the mixing speed is 600~800rpm, and the mixing time is 20~30min; in S3, the mixing speed is 400~600rpm, and the mixing time is 5~10min; in S4, the mixing speed is 400~600rpm, and the mixing time is 10~20min.

10. An application of the waterborne organosilicon coating according to any one of claims 1 to 7, characterized in that: The water-based organic silicon coating is used to form a coating on the surface of a flexible substrate.

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