Self-adhesive organic silicon coating as well as preparation method and construction method thereof

Abstract

The invention belongs to the field of coatings, and particularly relates to a self-adhesive organic silicon coating as well as a preparation method and a construction method thereof. The self-adhesive organic silicon coating provided by the invention is prepared from the following raw materials in parts by mass: 100 parts of vinyl silicone oil, 6-35 parts of pretreated white carbon black (or 5-25 parts of white carbon black and 1-10 parts of a white carbon black treating agent), 0.5-8 parts of a tackifier, 2-7 parts of hydrogen-containing silicone oil, 0.2-1 part of a reaction inhibitor, 0-20 parts of a viscosity modifier, 0-20 parts of color paste and 0.5-2 parts of a catalyst, the chemical structure of the tackifier is shown as a formula (I), and in the formula (I), R1 is alkyl, X is alkoxysilyl alkyl, and Y is epoxypropoxy alkyl. The self-adhesive organic silicon coating provided by the invention can still realize good adhesion to a substrate under the condition that a primer is not used. # imgabs0 #

Description

Technical Field

[0001] The invention belongs to the field of coatings, and in particular relates to a self-adhesive organosilicon coating and a preparation method and a construction method thereof. Background Art

[0002] Silicone coating is a coating with silicone or modified silicone as the main film-forming substance. It has a unique molecular structure with the main chain being -Si-O-Si-. This structure gives it excellent properties such as heat and cold resistance, electrical insulation, corona resistance, radiation resistance, moisture resistance, hydrophobicity, weather resistance, stain resistance and chemical corrosion resistance.

[0003] Due to their excellent properties, silicone coatings are widely used in many fields. For example, in the electrical industry, silicone coatings are used to manufacture insulation materials and corona-resistant coatings; in the construction and automotive industries, silicone coatings are used to manufacture weather-resistant and corrosion-resistant surface coatings.

[0004] Spraying is a common application method for silicone coatings. During spray application, the silicone coating is diluted before being sprayed onto the material. Because the solvent used for dilution can affect the activity of the silicone coating's tackifier, resulting in a decrease in the coating's adhesion, a specific primer must be pre-coated on the surface to ensure good adhesion of the silicone coating. Summary of the Invention

[0005] In view of this, the object of the present invention is to provide a self-adhesive organosilicon coating and a preparation method and an application method thereof. The self-adhesive organosilicon coating provided by the present invention can still achieve good adhesion to the substrate without using a primer.

[0006] The present invention provides a self-adhesive organosilicon coating. The raw materials of the self-adhesive organosilicon coating include, by weight, 100 parts of vinyl silicone oil, 5-25 parts of white carbon black, 1-10 parts of white carbon black treating agent, 0.5-8 parts of tackifier, 2-7 parts of hydrogenated silicone oil, 0.2-1 part of reaction inhibitor, 0-20 parts of viscosity modifier, 0-20 parts of color paste and 0.5-2 parts of catalyst.

[0007] Alternatively, the raw materials of the self-adhesive silicone coating include, by weight: 100 parts of vinyl silicone oil, 6 to 35 parts of pretreated silica, 0.5 to 8 parts of tackifier, 2 to 7 parts of hydrogenated silicone oil, 0.2 to 1 part of reaction inhibitor, 0 to 20 parts of viscosity modifier, 0 to 20 parts of color paste, and 0.5 to 2 parts of catalyst, wherein the pretreated silica is prepared by mixing 5 to 25 parts of silica with 1 to 10 parts of silica treatment agent;

[0008] The chemical structure of the tackifier is shown in formula (I):

[0009]

[0010] In formula (I), R 1 is an alkyl group, X is an alkoxysilylalkyl group, and Y is a glycidoxyalkyl group.

[0011] Preferably, the R 1 C1~C 12 of alkyl.

[0012] Preferably, the alkoxysilylalkyl group is one or more of trimethoxysilylethyl, triethoxysilylethyl, triisopropoxysilylethyl, trimethoxysilylpropyl and trimethoxysilylbutyl.

[0013] Preferably, the glycidoxyalkyl group is one or more of 2-glycidoxyethyl, 3-glycidoxypropyl and 4-glycidoxybutyl.

[0014] Preferably, the viscosity of the vinyl silicone oil at 25° C. is 1000 to 200,000 mPa.s, and the vinyl content is 0.04 to 1 wt%.

[0015] Preferably, the white carbon black treating agent is one or more of silazane, vinylsilazane and hydroxy silicone oil.

[0016] Preferably, the reaction inhibitor is one or more of methylbutynol, acetylene cyclohexanol, diethyl maleate and dibutyl maleate.

[0017] The present invention provides a method for preparing the self-adhesive organosilicon coating described in the above technical solution, comprising the following steps:

[0018] a) banburying vinyl silicone oil, white carbon black and a white carbon black treating agent, or banburying vinyl silicone oil and pretreated white carbon black to obtain a masterbatch;

[0019] b) mixing the masterbatch, tackifier, hydrogenated silicone oil, reaction inhibitor, viscosity modifier, color paste and catalyst to obtain a self-adhesive organosilicon coating.

[0020] Preferably, step a) specifically includes:

[0021] First, vinyl silicone oil, white carbon black and white carbon black treatment agent are preliminarily mixed under nitrogen protection, or vinyl silicone oil and pre-treated white carbon black are preliminarily mixed under nitrogen protection; then vacuuming and heating to continue mixing;

[0022] The temperature of the preliminary banburying is 10-40°C, and the temperature of the continued banburying is 200-220°C.

[0023] The present invention provides a construction method of a self-adhesive organosilicon coating, comprising the following steps:

[0024] The self-adhesive organosilicon coating described in the above technical solution or the self-adhesive organosilicon coating prepared by the preparation method described in the above technical solution is diluted, sprayed onto a substrate, and then dried to form an organosilicon coating.

[0025] Compared with the prior art, the present invention provides a self-adhesive organosilicon coating and its preparation method and construction method. In terms of mass, the raw materials of the self-adhesive organosilicon coating provided by the present invention include: 100 parts of vinyl silicone oil, 6 to 35 parts of pretreated white carbon black (or 5 to 25 parts of white carbon black and 1 to 10 parts of white carbon black treatment agent), 0.5 to 8 parts of tackifier, 2 to 7 parts of hydrogenated silicone oil, 0.2 to 1 part of reaction inhibitor, 0 to 20 parts of viscosity modifier, 0 to 20 parts of color paste, and 0.5 to 2 parts of catalyst; the chemical structure of the tackifier is shown in formula (I), where R 1 is an alkyl group, X is an alkoxysilylalkyl group, and Y is a glycidoxyalkyl group. The present invention addresses the problem of poor or no adhesion to substrates caused by the presence of diluents by optimizing the raw material formulation of the organosilicon coating, particularly by adding a tackifier with a specific chemical structure. This allows for excellent adhesion to substrates without the use of a primer. Furthermore, in the preferred technical solution provided by the present invention, the optimized selection of vinyl silicone oil, silica, and silica treatment agent further enhances the leveling performance of the organosilicon coating while maintaining mechanical strength. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0027] Figure 1 This is an infrared characterization spectrum of the structural tackifier of formula (i) provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0028] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0029] The present invention provides a self-adhesive organosilicon coating. The raw materials of the self-adhesive organosilicon coating include, by weight, 100 parts of vinyl silicone oil, 5-25 parts of white carbon black, 1-10 parts of white carbon black treating agent, 0.5-8 parts of tackifier, 2-7 parts of hydrogenated silicone oil, 0.2-1 part of reaction inhibitor, 0-20 parts of viscosity modifier, 0-20 parts of color paste and 0.5-2 parts of catalyst.

[0030] Alternatively, the raw materials of the self-adhesive silicone coating include, by mass, 100 parts of vinyl silicone oil, 6 to 35 parts of pretreated silica, 0.5 to 8 parts of tackifier, 2 to 7 parts of hydrogenated silicone oil, 0.2 to 1 part of reaction inhibitor, 0 to 20 parts of viscosity modifier, 0 to 20 parts of color paste and 0.5 to 2 parts of catalyst, and the pretreated silica is prepared by mixing 5 to 25 parts of silica with 1 to 10 parts of silica treatment agent.

[0031] In the organosilicon coating provided by the present invention, the viscosity of the vinyl silicone oil at 25°C is preferably 1000 to 200,000 mPa.s, more preferably 5000 to 100,000 mPa.s, and specifically can be 5000 mPa.s, 10000 mPa.s, 20000 mPa.s, 30000 mPa.s, 40000 mPa.s, 50000 mPa.s, 60000 mPa.s, or 70000 mPa. s, 80000 mPa.s, 90000 mPa.s or 100000 mPa.s; the vinyl content of the vinyl silicone oil is preferably 0.04-1 wt%, more preferably 0.06-0.4 wt%, specifically 0.06 wt%, 0.08 wt%, 0.1 wt%, 0.12 wt%, 0.15 wt%, 0.2 wt%, 0.25 wt%, 0.3 wt%, 0.35 wt% or 0.4 wt%.

[0032] In the organosilicon coating provided by the present invention, the vinyl silicone oil is preferably a mixture of low-viscosity vinyl silicone oil and high-viscosity vinyl silicone oil. The low-viscosity vinyl silicone oil preferably has a viscosity of 1,000 to 10,000 mPa.s at 25°C, and the high-viscosity vinyl silicone oil preferably has a viscosity of 40,000 to 100,000 mPa.s at 25°C. The mass ratio of the low-viscosity vinyl silicone oil to the high-viscosity vinyl silicone oil is preferably 3:(1 to 10), specifically 3:1, 3:2, 3:3, 3:4, 3:5, 3:6, 3:7, 3:8, 3:9, or 3:10.

[0033] In the organosilicon coating provided by the present invention, the specific surface area of the white carbon black is preferably ≤250m 2 / g, more preferably 50 to 200 m 2 / g.

[0034] In the organosilicon coating provided by the present invention, with the content of vinyl silicone oil in the coating raw material as 100 parts by mass, the content of white carbon black in the coating raw material can specifically be 5 parts by mass, 6 parts by mass, 7 parts by mass, 8 parts by mass, 9 parts by mass, 10 parts by mass, 11 parts by mass, 12 parts by mass, 13 parts by mass, 14 parts by mass, 15 parts by mass, 16 parts by mass, 17 parts by mass, 18 parts by mass, 19 parts by mass, 20 parts by mass, 21 parts by mass, 22 parts by mass, 23 parts by mass, 24 parts by mass or 25 parts by mass.

[0035] In the organosilicon coating provided by the present invention, the white carbon black treatment agent is preferably one or more of silazane, vinylsilazane and hydroxy silicone oil; the silazane is preferably hexamethyldisilazane; the vinylsilazane is preferably tetramethyldivinyldisilazane; the hydroxyl content of the hydroxy silicone oil is preferably 5-10wt%, specifically 5wt%, 5.5wt%, 6wt%, 6.5wt%, 7wt%, 7.5wt%, 8wt%, 8.5wt%, 9wt%, 9.5wt% or 10wt%; the viscosity of the hydroxy silicone oil at 25°C is preferably 20-35CS; the mass ratio of the silazane and vinylsilazane is preferably (1-5):1, specifically 1:1, 2:1, 3:1, 4:1 or 5:1; the mass ratio of the silazane and hydroxy silicone oil is preferably (4-8):1, specifically 4:1, 5:1, 6:1, 7:1 or 8:1.

[0036] In the organosilicon coating provided by the present invention, taking the content of vinyl silicone oil in the coating raw material as 100 parts by mass, the content of the white carbon black treatment agent in the coating raw material can specifically be 1 part by mass, 2 parts by mass, 3 parts by mass, 4 parts by mass, 5 parts by mass, 6 parts by mass, 7 parts by mass, 8 parts by mass, 9 parts by mass or 10 parts by mass.

[0037] In the organosilicon coating provided by the present invention, with the content of vinyl silicone oil in the coating raw material as 100 parts by mass, the content of the pretreated silica in the coating raw material may specifically be 6 parts by mass, 7 parts by mass, 8 parts by mass, 9 parts by mass, 10 parts by mass, 11 parts by mass, 12 parts by mass, 13 parts by mass, 14 parts by mass, 15 parts by mass, 16 parts by mass, 17 parts by mass, 18 parts by mass, 19 parts by mass, 20 parts by mass, 21 parts by mass, 22 parts by mass, 23 parts by mass, 24 parts by mass, 25 parts by mass, 26 parts by mass, 27 parts by mass, 28 parts by mass, 29 parts by mass, 30 parts by mass, 31 parts by mass, 32 parts by mass, 33 parts by mass, 34 parts by mass or 35 parts by mass.

[0038] In the organosilicon coating provided by the present invention, the chemical structure of the tackifier is shown in formula (I):

[0039]

[0040] In formula (I), R 1 is an alkyl group, preferably C1 to C 12 The alkyl group may be C1 alkyl, C2 alkyl, C3 alkyl, C4 alkyl, C5 alkyl, C6 alkyl, C7 alkyl, C8 alkyl, C9 alkyl, C 10 Alkyl, C 11 Alkyl or C 12 alkyl; X is an alkoxysilylalkyl group, preferably one or more of trimethoxysilylethyl, triethoxysilylethyl, triisopropoxysilylethyl, trimethoxysilylpropyl and trimethoxysilylbutyl; Y is a glycidoxyalkyl group, preferably one or more of 2-glycidoxyethyl, 3-glycidoxypropyl and 4-glycidoxybutyl.

[0041] In the organosilicon coating provided by the present invention, the chemical structure of the tackifier may be specifically shown as formula (i):

[0042]

[0043] In the organosilicon coating provided by the present invention, taking the compound of formula (i) as an example, the specific preparation steps of the tackifier are as follows:

[0044] (1) Replace the reactor with a condenser and a thermometer with nitrogen two or three times, add n-heptane and platinum catalyst to the reactor, stir and heat to 50-90°C;

[0045] (2) Dimethyldivinylsilane and tetramethylcyclotetrasiloxane were mixed uniformly in proportion, and then added dropwise to the reaction kettle. After the addition was complete, the mixture was stirred and reacted for 2 to 5 hours;

[0046] (3) Raise the oil temperature to 100-140°C, add vinyltrimethoxysilane dropwise to the reactor, and react for 2-5 hours after the addition is complete;

[0047] (4) Maintaining the oil temperature at 100-140°C, add allyl glycidyl ether dropwise to the reactor and allow to react for 2-5 hours after the addition is complete;

[0048] (5) After the reaction is completed, the temperature is lowered to below 50°C and the catalyst is removed by adsorption on activated carbon;

[0049] (6) distilling under reduced pressure at 100-140° C. and a vacuum degree of less than -0.1 MPa to obtain the tackifier.

[0050] In the organosilicon coating provided by the present invention, with the content of vinyl silicone oil in the coating raw material as 100 parts by mass, the content of the tackifier in the coating raw material can specifically be 0.5 parts by mass, 1 part by mass, 1.5 parts by mass, 2 parts by mass, 2.5 parts by mass, 3 parts by mass, 3.5 parts by mass, 4 parts by mass, 4.5 parts by mass, 5 parts by mass, 5.5 parts by mass, 6 parts by mass, 6.5 parts by mass, 7 parts by mass, 7.5 parts by mass or 8 parts by mass.

[0051] In the organosilicon coating provided by the present invention, the hydrogen-containing silicone oil is preferably end-side hydrogen-containing silicone oil and / or side hydrogen-containing silicone oil; the hydrogen content of the hydrogen-containing silicone oil is preferably 0.5-1.5wt%, specifically 0.5wt%, 0.6wt%, 0.7wt%, 0.8wt%, 0.9wt%, 1wt%, 1.1wt%, 1.2wt%, 1.3wt%, 1.4wt% or 1.5wt%.

[0052] In the organosilicon coating provided by the present invention, with the content of vinyl silicone oil in the coating raw material as 100 parts by mass, the content of the hydrogenated silicone oil in the coating raw material can specifically be 2 parts by mass, 2.5 parts by mass, 3 parts by mass, 3.5 parts by mass, 4 parts by mass, 4.5 parts by mass, 5 parts by mass, 5.5 parts by mass, 6 parts by mass, 6.5 parts by mass or 7 parts by mass.

[0053] In the organosilicon coating provided by the present invention, the reaction inhibitor is preferably one or more of methylbutynol, acetylene cyclohexanol, diethyl maleate and dibutyl maleate.

[0054] In the organosilicon coating provided by the present invention, with the content of vinyl silicone oil in the coating raw material as 100 parts by mass, the content of the reaction inhibitor in the coating raw material can specifically be 0.2 parts by mass, 0.25 parts by mass, 0.3 parts by mass, 0.35 parts by mass, 0.4 parts by mass, 0.45 parts by mass, 0.5 parts by mass, 0.55 parts by mass, 0.6 parts by mass, 0.65 parts by mass, 0.7 parts by mass, 0.75 parts by mass, 0.8 parts by mass, 0.85 parts by mass, 0.9 parts by mass, 0.95 parts by mass or 1 part by mass.

[0055] In the organosilicon coating provided by the present invention, the viscosity modifier is an organic solvent, preferably one or more of isododecane, D65 solvent oil, ethyl acetate and butyl acetate.

[0056] In the organosilicon coating provided by the present invention, with the content of vinyl silicone oil in the coating raw material as 100 parts by mass, the content of the viscosity regulator in the coating raw material can specifically be 0 parts by mass, 1 part by mass, 2 parts by mass, 3 parts by mass, 4 parts by mass, 5 parts by mass, 6 parts by mass, 7 parts by mass, 8 parts by mass, 9 parts by mass, 10 parts by mass, 11 parts by mass, 12 parts by mass, 13 parts by mass, 14 parts by mass, 15 parts by mass, 16 parts by mass, 17 parts by mass, 18 parts by mass, 19 parts by mass or 20 parts by mass.

[0057] In the organosilicon coating provided by the present invention, the color paste is not particularly limited, and those skilled in the art can select a suitable color paste according to actual needs.

[0058] In the organosilicon coating provided by the present invention, with the content of vinyl silicone oil in the coating raw material as 100 parts by mass, the content of the color paste in the coating raw material can specifically be 0 parts by mass, 1 part by mass, 2 parts by mass, 3 parts by mass, 4 parts by mass, 5 parts by mass, 6 parts by mass, 7 parts by mass, 8 parts by mass, 9 parts by mass, 10 parts by mass, 11 parts by mass, 12 parts by mass, 13 parts by mass, 14 parts by mass, 15 parts by mass, 16 parts by mass, 17 parts by mass, 18 parts by mass, 19 parts by mass or 20 parts by mass.

[0059] In the organosilicon coating provided by the present invention, the catalyst is preferably a platinum catalyst, and the Pt content of the platinum catalyst is preferably 1000-2000 ppm, specifically 1000 ppm, 1100 ppm, 1200 ppm, 1300 ppm, 1400 ppm, 1500 ppm, 1600 ppm, 1700 ppm, 1800 ppm, 1900 ppm or 2000 ppm.

[0060] In the organosilicon coating provided by the present invention, with the content of vinyl silicone oil in the coating raw material as 100 parts by mass, the content of the catalyst in the coating raw material may specifically be 0.5 parts by mass, 0.6 parts by mass, 0.7 parts by mass, 0.8 parts by mass, 0.9 parts by mass, 1 part by mass, 1.1 parts by mass, 1.2 parts by mass, 1.3 parts by mass, 1.4 parts by mass, 1.5 parts by mass, 1.6 parts by mass, 1.7 parts by mass, 1.8 parts by mass, 1.9 parts by mass or 2 parts by mass.

[0061] The present invention also provides a method for preparing the self-adhesive organosilicon coating described in the above technical solution, comprising the following steps:

[0062] a) banburying vinyl silicone oil, white carbon black and a white carbon black treating agent, or banburying vinyl silicone oil and pretreated white carbon black to obtain a masterbatch;

[0063] b) mixing the masterbatch, tackifier, hydrogenated silicone oil, reaction inhibitor, viscosity modifier, color paste and catalyst to obtain a self-adhesive organosilicon coating.

[0064] In the method for preparing the organosilicon coating provided by the present invention, the specific process of step a) preferably includes: firstly performing preliminary banburying of the vinyl silicone oil, white carbon black and the white carbon black treating agent under nitrogen protection, or performing preliminary banburying of the vinyl silicone oil and pretreated white carbon black under nitrogen protection; then evacuating the mixture and heating to continue banburying. Wherein, the temperature of the preliminary banburying is preferably 10-40°C, specifically 10°C, 15°C, 20°C, 25°C (room temperature), 30°C, 35°C or 40°C; the time of the preliminary banburying is preferably 0.5-5h, specifically 0.5h, 1h, 1.5h, 2h, 2.5h, 3h, 3.5h, 4h, 4.5h or 5h; the temperature of the continued banburying is preferably 200-220°C, specifically 200°C, 203°C, 205°C, 207°C, 210°C, 213°C, 215°C, 217°C or 220°C; the time of the continued banburying is preferably 0.5-5h, specifically 0.5h, 1h, 1.5h, 2h, 2.5h, 3h, 3.5h, 4h, 4.5h or 5h.

[0065] In the method for preparing the organosilicon coating provided by the present invention, in step b), the masterbatch is preferably ground before mixing, wherein the number of grinding times is preferably 1 to 5 times, specifically 1 time, 2 times, 3 times, 4 times, or 5 times.

[0066] The present invention also provides a construction method of a self-adhesive organosilicon coating, comprising the following steps:

[0067] The self-adhesive organosilicon coating described in the above technical solution or the self-adhesive organosilicon coating prepared by the preparation method described in the above technical solution is diluted, sprayed onto a substrate, and then dried to form an organosilicon coating.

[0068] In the construction method provided by the present invention, the diluents used for dilution are preferably a first diluent and a second diluent, the first diluent being n-heptane and / or white spirit, and the second diluent being methyl isobutyl ketone (MIBK) or other organic solvent that dissolves silicone rubber. The amount of the second diluent is preferably 15 to 70 wt% of the amount of the first diluent, specifically 15 wt%, 20 wt%, 25 wt%, 30 wt%, 35 wt%, 40 wt%, 45 wt%, 50 wt%, 55 wt%, 60 wt%, 65 wt%, or 70 wt%. The total amount of the diluents is preferably 2 to 5 times the mass of the vinyl silicone oil in the coating, specifically 2 times, 2.5 times, 3 times, 3.5 times, 4 times, 4.5 times, or 5 times.

[0069] In the construction method provided herein, the substrate is preferably a non-silicon material, including but not limited to one or more of metal, glass, ceramic, and plastic. The metal includes pure metal and / or alloys, including but not limited to one or more of stainless steel, zinc alloy, magnesium alloy, and aluminum alloy; and the plastic includes but not limited to one or more of polycarbonate (PC), acrylonitrile-butadiene-styrene copolymer (ABS), polyethylene terephthalate (PET), and polyimide (PI).

[0070] In the construction method provided by the present invention, the dry film thickness of the spraying is preferably 50 to 300 μm, specifically 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm, 150 μm, 160 μm, 170 μm, 180 μm, 190 μm, 200 μm, 210 μm, 220 μm, 230 μm, 240 μm, 250 μm, 260 μm, 270 μm, 280 μm, 290 μm or 300 μm.

[0071] In the construction method provided by the present invention, after spraying, before drying, it is preferably left to stand for a period of time to assist in leveling and defoaming the coating. The standing time is preferably 5 to 15 minutes, specifically 5 minutes, 6 minutes, 7 minutes, 8 minutes, 9 minutes, 10 minutes, 11 minutes, 12 minutes, 13 minutes, 14 minutes, or 15 minutes.

[0072] In the construction method provided by the present invention, the drying temperature is preferably 80-180°C, specifically 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C or 180°C; the drying time is not particularly limited and can be selected according to actual conditions.

[0073] In the construction method provided by the present invention, if the surface of the substrate needs to have a smooth and refreshing effect, after forming the silicone coating, hand-feeling oil can be sprayed on the surface of the material and dried.

[0074] The technical solution provided by the present invention significantly improves the performance of organosilicon coatings by optimizing the raw material formula, preparation method, and application process of organosilicon coatings. More specifically, the technical solution of the present invention has at least the following beneficial effects:

[0075] (1) The raw material formula of silicone coatings was optimized, especially the addition of a tackifier with a specific chemical structure, which solved the problem of poor adhesion of silicone coatings to substrates in the presence of diluents.

[0076] (2) Optimizing the selection of vinyl silicone oil, white carbon black and white carbon black treatment agent can reduce the viscosity of the coating and thus improve the leveling effect of the coating.

[0077] (3) It is preferred to use low-viscosity and high-viscosity vinyl silicone oils in combination, and control the vinyl content between 0.06 and 0.4 wt%, so that the coating can achieve both leveling and strength.

[0078] (4) Optimizing the selection of reaction inhibitors can improve the problem of thick spray foaming.

[0079] (5) The mixing temperature during coating preparation is preferably increased to 200-220°C, which can promote the full reaction between silica and silicone oil and remove small molecular by-products.

[0080] (6) By controlling the amount of catalyst used and preferably allowing the coating to stand still after spraying, the problem of foaming due to thick spraying can be improved.

[0081] For the purpose of greater clarity, the present invention is described in detail with reference to the following examples and comparative examples.

[0082] In the following embodiments of the present invention, the tackifier used has the structure of formula (i), and the preparation steps are as follows:

[0083] (1) Replace the reactor equipped with a condenser and a thermometer with nitrogen two or three times, add n-heptane and platinum catalyst to the reactor, stir and heat to 70°C;

[0084] (2) Dimethyldivinylsilane and tetramethylcyclotetrasiloxane were mixed uniformly in proportion, and then added dropwise to the reaction kettle. After the addition was complete, the mixture was stirred and reacted for 3 hours;

[0085] (3) Raise the oil temperature to 120°C, add vinyltrimethoxysilane dropwise to the reactor, and allow to react for 35 hours after the addition is complete;

[0086] (4) Maintaining the oil temperature at 120°C, add allyl glycidyl ether dropwise to the reactor and allow to react for 3 hours after the addition is complete;

[0087] (5) After the reaction is completed, the temperature is lowered to below 50°C and the catalyst is removed by adsorption on activated carbon;

[0088] (6) distillation under reduced pressure (temperature 120° C., vacuum degree <-0.1 MPa) to obtain a structural tackifier of formula (i).

[0089] The above-prepared structural tackifier of formula (i) was subjected to infrared characterization, and the results were as follows: Figure 1 shown. Figure 1 The characteristic peak group information is: 2963cm -1 ,2879cm -1 →-CH3, 2942cm-1 →-CH2, 2841cm -1 ,1192cm -1 →Si-O-CH3, 2163cm -1 →Si-H, 1261cm -1 ,805cm -1 →Si-CH3, 1085cm -1 →Si-O-Si, 908cm -1 →Epoxy group.

[0090] Example 1

[0091] 100 parts by mass of vinyl silicone oil with a viscosity of 5000 mPa.s at 25°C and a vinyl content of 0.15 wt% and 7.5 parts by mass of hexamethyldisilazane were added to a kneader, and 25 parts by mass of a 200 m 2 / g of white carbon black was mixed with nitrogen at room temperature for 1.5h, then vacuumed and heated to 200℃, mixed for 3h to obtain the reinforced masterbatch.

[0092] After the masterbatch was ground three times on a three-roll mill, 3 parts by mass of side hydrogenated silicone oil with a hydrogen content of 0.7 wt%, 4 parts by mass of a structural tackifier of formula (i), 0.5 parts by mass of methylbutynol, and 15 parts by mass of isododecane were added and mixed uniformly. 5 parts by mass of a color paste and 0.5 parts by mass of a platinum catalyst with a Pt content of 1500 ppm were then added to obtain a self-adhesive silicone composition coating.

[0093] 250 parts by mass of n-heptane and 50 parts by mass of methyl isobutyl ketone were added to the above-mentioned coating, and then spraying was carried out; the spraying construction was carried out on metal, glass, and plastic substrates, respectively, and the spraying thickness (dry film thickness) was 180±20 μm; after spraying, it was allowed to stand for 10 minutes, and then dried uniformly at 80°C for 20 minutes, and then the coating sprayed on the metal and glass substrates was heated to 160°C and continued to dry for 15 minutes; after completing the above-mentioned drying operation, matte skin-feel silicone hand oil was continued to be sprayed on the surface of the substrate, and then dried, among which the plastic substrate was dried at 80°C for 60 minutes, and the metal and glass substrates were dried at 180°C for 30 minutes.

[0094] Example 2

[0095] 100 parts by mass of vinyl silicone oil with a viscosity of 60,000 mPa.s at 25°C and a vinyl content of 0.08 wt%, 2 parts by mass of hexamethyldisilazane and 1 part by mass of tetramethyldivinyldisilazane were added to a kneader, and 15 parts by mass of a specific surface area of 150 m 2 / g of white carbon black was mixed with nitrogen at room temperature for 2h, then vacuumed and heated to 210℃, and mixed for 4h to obtain the reinforced masterbatch.

[0096] After the masterbatch was ground three times on a three-roll mill, 3 parts by mass of end-side hydrogenated silicone oil with a hydrogen content of 0.8 wt%, 5 parts by mass of a structural tackifier of formula (i), 0.2 parts by mass of methylbutynol, and 15 parts by mass of D65 solvent oil were added and mixed evenly. 5 parts by mass of a color paste and 1 part by mass of a platinum catalyst with a Pt content of 1500 ppm were then added to obtain a self-adhesive silicone composition coating.

[0097] 200 parts by mass of n-heptane and 100 parts by mass of methyl isobutyl ketone were added to the above-mentioned coating, and then spraying was carried out; the spraying construction was carried out on metal, glass, and plastic substrates, respectively, and the spraying thickness (dry film thickness) was 180±20 μm; after spraying, it was allowed to stand for 10 minutes, and then dried uniformly at 80°C for 20 minutes, and then the coating sprayed on the metal and glass substrates was heated to 160°C and continued to dry for 15 minutes; after completing the above-mentioned drying operation, matte skin-feel silicone hand oil was continued to be sprayed on the surface of the substrate, and then dried, among which the plastic substrate was dried at 80°C for 60 minutes, and the metal and glass substrates were dried at 180°C for 30 minutes.

[0098] Example 3

[0099] 100 parts by mass of vinyl silicone oil with a viscosity of 100,000 mPa.s at 25°C and a vinyl content of 0.06 wt% and 3 parts by mass of hexamethyldisilazane were added to the kneader, and 15 parts by mass of a 90 m2 specific surface area silicone oil were added in batches. 2 / g of white carbon black was mixed with nitrogen at room temperature for 1.5h, then vacuumed and heated to 200℃, mixed for 3h to obtain the reinforced masterbatch.

[0100] After the masterbatch was ground three times on a three-roll mill, 5 parts by mass of end-side hydrogenated silicone oil with a hydrogen content of 0.8 wt%, 0.5 parts by mass of a structural tackifier of formula (i), 1 part by mass of methylbutynol, and 15 parts by mass of ethyl acetate were added and mixed uniformly. 5 parts by mass of a color paste and 3 parts by mass of a platinum catalyst with a Pt content of 1500 ppm were then added to obtain a self-adhesive silicone composition coating.

[0101] 230 parts by mass of n-heptane and 70 parts by mass of methyl isobutyl ketone were added to the above-mentioned coating, and then spraying was carried out; the spraying construction was carried out on metal, glass, and plastic substrates, respectively, and the spraying thickness (dry film thickness) was 180±20 μm; after spraying, it was allowed to stand for 10 minutes, and then dried uniformly at 80°C for 20 minutes, and then the coating sprayed on the metal and glass substrates was heated to 160°C and continued to dry for 15 minutes; after completing the above-mentioned drying operation, matte skin-feel silicone hand oil was continued to be sprayed on the surface of the substrate, and then dried, among which the plastic substrate was dried at 80°C for 60 minutes, and the metal and glass substrates were dried at 180°C for 30 minutes.

[0102] Example 4

[0103] 100 parts by mass of vinyl silicone oil with a viscosity of 60,000 mPa.s at 25°C and a vinyl content of 0.08 wt%, 6 parts by mass of hexamethyldisilazane and 1 part by mass of hydroxy silicone oil with a hydroxy content of 8.5 wt% and a viscosity of 20-35 CS at 25°C were added to a kneader, and 15 parts by mass of a 90 m3 specific surface area silicone oil were added in batches. 2 / g of white carbon black was mixed with nitrogen at room temperature for 4 hours, then vacuumed and heated to 220℃, and mixed for 2 hours to obtain the reinforced masterbatch.

[0104] After the masterbatch was ground three times on a three-roll mill, 2 parts by mass of side hydrogen-containing silicone oil with a hydrogen content of 0.7 wt%, 2 parts by mass of end hydrogen-containing silicone oil with a hydrogen content of 0.8 wt%, 4 parts by mass of a structural tackifier of formula (i), 0.8 parts by mass of methylbutynol, and 15 parts by mass of butyl acetate were added and mixed uniformly. 5 parts by mass of a color paste and 0.5 parts by mass of a platinum catalyst with a Pt content of 1500 ppm were then added to obtain a self-adhesive silicone composition coating.

[0105] 180 parts by mass of n-heptane and 120 parts by mass of methyl isobutyl ketone were added to the above-mentioned coating, and then spraying was carried out; the spraying construction was carried out on metal, glass, and plastic substrates, respectively, and the spraying thickness (dry film thickness) was 180±20μm; after spraying, the coating was allowed to stand for 10 minutes, and then dried uniformly at 80°C for 15 minutes. Then, the coating sprayed on the metal and glass substrates was heated to 160°C and continued to dry for 45 minutes, while the coating sprayed on the plastic substrate was maintained at 80°C and continued to dry for 60 minutes.

[0106] Example 5

[0107] 70 parts by mass of a vinyl silicone oil having a viscosity of 60,000 mPa.s at 25°C and a vinyl content of 0.08 wt% and 30 parts by mass of a vinyl silicone oil having a viscosity of 5,000 mPa.s at 25°C and a vinyl content of 0.15 wt% and 3 parts by mass of hexamethyldisilazane and 1 part by mass of tetramethyldivinyldisilazane were added to a kneader, and 18 parts by mass of a slurry having a specific surface area of 150 m 2 / g of white carbon black was mixed at room temperature with nitrogen for 4 hours, then vacuumed and heated to 200℃, and mixed for 4 hours to obtain the reinforced masterbatch.

[0108] After the masterbatch was ground three times on a three-roll mill, 2.5 parts by mass of side hydrogen-containing silicone oil with a hydrogen content of 0.7 wt%, 2 parts by mass of end hydrogen-containing silicone oil with a hydrogen content of 0.8 wt%, 8 parts by mass of a structural tackifier of formula (i), 0.6 parts by mass of methylbutynol, and 15 parts by mass of butyl acetate were added and mixed uniformly. 5 parts by mass of a color paste and 0.5 parts by mass of a platinum catalyst with a Pt content of 1500 ppm were then added to obtain a self-adhesive silicone composition coating.

[0109] 200 parts by mass of n-heptane and 100 parts by mass of methyl isobutyl ketone were added to the above-mentioned coating, and then spraying was carried out; the spraying construction was carried out on metal, glass, and plastic substrates, respectively, with a spraying thickness (dry film thickness) of 180±20μm; after spraying, the coating was allowed to stand for 10 minutes and then dried uniformly at 80°C for 15 minutes. The coating sprayed on the metal and glass substrates was then heated to 160°C and dried for 45 minutes, while the coating sprayed on the plastic substrate was maintained at 80°C and dried for 60 minutes.

[0110] Comparative Example 1

[0111] 100 parts by mass of vinyl silicone oil with a viscosity of 60,000 mPa.s at 25°C and a vinyl content of 0.08 wt% and 10 parts by mass of silazane were added to a kneader, and 30 parts by mass of a silane with a specific surface area of 400 m 2 / g of white carbon black was mixed with nitrogen at room temperature for 2h, then vacuumed and heated to 180℃, and mixed for 3h to obtain the reinforced masterbatch.

[0112] After grinding the masterbatch three times on a three-roll mill, 3 parts by mass of side hydrogenated silicone oil with a hydrogen content of 0.7 wt%, 0.5 parts by mass of methylbutynol, and 15 parts by mass of butyl acetate were added and mixed evenly. Then, 5 parts by mass of color paste and 0.5 parts by mass of platinum catalyst with a Pt content of 1500 ppm were added to obtain a silicone composition coating.

[0113] 180 parts by mass of n-heptane and 120 parts by mass of methyl isobutyl ketone were added to the above-mentioned coating, and then spraying was carried out; the spraying construction was carried out on metal, glass, and plastic substrates, respectively, and the spraying thickness (dry film thickness) was 180±20μm; after spraying, the coating was allowed to stand for 10 minutes, and then dried uniformly at 80°C for 15 minutes. Then, the coating sprayed on the metal and glass substrates was heated to 160°C and continued to dry for 45 minutes, while the coating sprayed on the plastic substrate was maintained at 80°C and continued to dry for 60 minutes.

[0114] Comparative Example 2

[0115] 50 parts by mass of a vinyl silicone oil having a viscosity of 60,000 mPa.s at 25°C and a vinyl content of 0.08 wt% and 50 parts by mass of a vinyl silicone oil having a viscosity of 10,000 mPa.s at 25°C and a vinyl content of 0.12 wt% and 6 parts by mass of silazane were added to a kneader, and 25 parts by mass of a 200 m 2 / g of white carbon black was mixed with nitrogen at room temperature for 2h, then vacuumed and heated to 200℃, and mixed for 2h to obtain the reinforced masterbatch.

[0116] After grinding the masterbatch three times on a three-roll mill, 2.5 parts by mass of side hydrogen-containing silicone oil with a hydrogen content of 0.7wt%, 2 parts by mass of side hydrogen-containing silicone oil with a hydrogen content of 0.8wt%, 8 parts by mass of a composition of vinyltrimethoxysilane oligomer, methacryloxytrimethoxysilane oligomer, and γ-(2,3-epoxypropoxy)propyltrimethoxysilane oligomer in a mass ratio of 1:2:3, 0.5 parts by mass of methylbutynol, and 15 parts by mass of D65 solvent oil were added and mixed evenly. Then, 5 parts by mass of color paste and 0.5 parts by mass of platinum catalyst with a Pt content of 1500ppm were added to obtain a silicone composition coating.

[0117] 180 parts by mass of n-heptane and 120 parts by mass of methyl isobutyl ketone were added to the above-mentioned coating, and then spraying was carried out; the spraying construction was carried out on metal, glass, and plastic substrates, respectively, and the spraying thickness (dry film thickness) was 180±20μm; after spraying, the coating was allowed to stand for 10 minutes, and then dried uniformly at 80°C for 15 minutes. Then, the coating sprayed on the metal and glass substrates was heated to 160°C and continued to dry for 45 minutes, while the coating sprayed on the plastic substrate was maintained at 80°C and continued to dry for 60 minutes.

[0118] Performance Testing

[0119] The performance tests were conducted on the self-adhesive organosilicon composition coatings prepared in Examples 1 to 5 and the comparative example. The results are shown in Table 1.

[0120] Table 1 Silicone coating performance test data

[0121]

[0122]

[0123] In Table 1, the test method for evaluating adhesion using the 100-grid coin scratch method is as follows:

[0124] Draw 5×5 2mm×2mm small grids on the surface of the test sample. Each line should reach the bottom layer of the coating. Use a brush to clean the debris in the test area. Use a 1 RMB coin and a force of 1 kg to scrape vertically:

[0125] Level 0: After 0-2 scratches, the paint film peels off over a large area and has no adhesion;

[0126] Level 1: Scratched ≤10 times, the scratched area and nearby areas are completely peeled off, and the adhesion is very poor;

[0127] Level 2: scratched ≤ 20 times, the paint film on the scratched part is completely peeled off, and the adhesion is poor;

[0128] Level 3: scratched 20 times, the paint film partially falls off at the scratched part, and the adhesion is average;

[0129] Level 4: scratched 20 times, the paint film on the scratched part has no obvious shedding, and is damaged after repeated scratching, and the adhesion is good;

[0130] Level 5: Scratched 20 times, the paint film on the scratched part does not fall off, and there is no damage after repeated scratching. Slight scratch marks are allowed, and the adhesion is very good.

[0131] In Table 1, the strength test method is: use a 1 RMB coin and scrape it vertically on the test part 40 times with a force of 1 kg to observe whether there is any damage.

[0132] In Table 1, the method for the adhesion test is as follows: boil in deionized water at 99.5±0.5°C for 2 hours, let stand at room temperature for 2 hours, and then perform the adhesion test. The test method refers to the 100-grid coin scratch method.

[0133] In Table 1, the specific operation of the dishwasher test is as follows: add 20-25g of Liangdi brand dishwashing powder into the dishwasher, place the test cup on the bottom rack of the dishwasher, and select the "Standard Wash" program; start the wash cycle, and thoroughly clean, rinse, and dry the test cup, which takes about 1.5 hours. Remove the sample and let it stand for 15 minutes. This constitutes one cycle. After every 25 cycles, perform an adhesion test using the 100-grid coin scratch method.

[0134] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A self-adhesive silicone coating, characterized in that: The raw materials of the self-adhesive silicone coating include, by mass, 100 parts of vinyl silicone oil, 5 to 25 parts of white carbon black, 1 to 10 parts of white carbon black treating agent, 0.5 to 8 parts of tackifier, 2 to 7 parts of hydrogenated silicone oil, 0.2 to 1 part of reaction inhibitor, 0 to 20 parts of viscosity modifier, 0 to 20 parts of color paste and 0.5 to 2 parts of catalyst; Alternatively, the raw materials of the self-adhesive silicone coating include, by weight: 100 parts of vinyl silicone oil, 6 to 35 parts of pretreated silica, 0.5 to 8 parts of tackifier, 2 to 7 parts of hydrogenated silicone oil, 0.2 to 1 part of reaction inhibitor, 0 to 20 parts of viscosity modifier, 0 to 20 parts of color paste, and 0.5 to 2 parts of catalyst, wherein the pretreated silica is prepared by mixing 5 to 25 parts of silica with 1 to 10 parts of silica treatment agent; The chemical structure of the tackifier is shown in formula (I): In formula (I), R 1 is an alkyl group, X is an alkoxysilylalkyl group, and Y is a glycidoxyalkyl group.

2. The self-adhesive silicone coating according to claim 1, characterized in that The R 1 C1~C 12 of alkyl.

3. The self-adhesive silicone coating according to claim 1, characterized in that: The alkoxysilylalkyl group is one or more of trimethoxysilylethyl, triethoxysilylethyl, triisopropoxysilylethyl, trimethoxysilylpropyl and trimethoxysilylbutyl.

4. The self-adhesive silicone coating according to claim 1, characterized in that The glycidoxyalkyl group is one or more of 2-glycidoxyethyl, 3-glycidoxypropyl and 4-glycidoxybutyl.

5. The self-adhesive silicone coating according to claim 1, characterized in that: The vinyl silicone oil has a viscosity of 1000 to 200000 mPa.s at 25° C. and a vinyl content of 0.04 to 1 wt %.

6. The self-adhesive silicone coating according to claim 1, characterized in that The white carbon black treating agent is one or more of silazane, vinylsilazane and hydroxy silicone oil.

7. The self-adhesive silicone coating according to claim 1, characterized in that: The reaction inhibitor is one or more of methylbutynol, acetylene cyclohexanol, diethyl maleate and dibutyl maleate.

8. A method for preparing the self-adhesive organosilicon coating according to any one of claims 1 to 7, characterized in that: The following steps are involved: a) banburying vinyl silicone oil, white carbon black and a white carbon black treating agent, or banburying vinyl silicone oil and pretreated white carbon black to obtain a masterbatch; b) mixing the masterbatch, tackifier, hydrogenated silicone oil, reaction inhibitor, viscosity modifier, color paste and catalyst to obtain a self-adhesive organosilicon coating.

9. The preparation method according to claim 8, characterized in that Step a) specifically includes: First, vinyl silicone oil, white carbon black and white carbon black treatment agent are preliminarily mixed under nitrogen protection, or vinyl silicone oil and pre-treated white carbon black are preliminarily mixed under nitrogen protection; then vacuuming and heating to continue mixing; The temperature of the preliminary banburying is 10-40°C, and the temperature of the continued banburying is 200-220°C.

10. A construction method for a self-adhesive silicone coating, characterized in that: The following steps are involved: The self-adhesive organosilicon coating according to any one of claims 1 to 7 or the self-adhesive organosilicon coating prepared by the preparation method according to any one of claims 8 to 9 is diluted, sprayed onto a substrate, and then dried to form an organosilicon coating.

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