Preparation method and use method of one-component polyurea anti-icing coating

Abstract

A method for preparing a one-component polyurea anti-icing coating and a method for using the same belong to the field of anti-icing coatings. The present invention aims to solve the problem that existing polyurea coatings cannot delay the freezing time and reduce the ice adhesion strength, and to solve the problem that two-component system coatings need to mix the two components before construction. Methods: 1. Synthesis of silicon-containing prepolymers; 2. Synthesis of silicon-modified latent curing agents; 3. Preparation of one-component polyurea anti-icing coatings. The present invention is used for the preparation and use of one-component polyurea anti-icing coatings.

Description

Technical Field

[0001] The invention belongs to the field of anti-icing coatings. Background Art

[0002] Icing poses a serious threat to infrastructure, transportation, and daily life. Traditional active anti-icing / de-icing technologies such as electric heating, mechanical external force, and spraying de-icing fluid require the use of additional devices, which consume a lot of energy, are expensive, and are prone to environmental pollution. In contrast, passive anti-icing / de-icing materials do not require modification or upgrading of existing structures and devices. They consume no energy and are pollution-free during use. They can delay the freezing time and reduce the adhesion between ice and the substrate surface. They are anti-icing / de-icing technologies with great development potential. However, under harsh outdoor working conditions, passive anti-icing / de-icing materials are prone to physical damage or chemical corrosion, which reduces or even completely loses their anti-icing performance. Durability is a severe challenge in promoting the application of passive anti-icing / de-icing materials in the engineering field.

[0003] Polyurea is an elastomeric material obtained by the chain extension reaction of isocyanate prepolymers and amino compounds. It has the advantages of high strength and high toughness and is widely used in waterproofing, bulletproofing and anti-corrosion fields. However, the existing polyurea coating has a high surface energy and a large friction coefficient, and does not have the characteristics of delaying the freezing time and reducing the ice adhesion strength. In addition, isocyanate and primary amine compounds react very quickly, so special high-pressure equipment is required for spraying during the construction of polyurea. Although the reaction of secondary amines with isocyanate groups can slow down the reaction rate, it is still a two-component system coating. Before construction, the two components need to be mixed before construction. The steps are cumbersome, and the mixed coating has a certain length of construction window period, which brings challenges to on-site construction. Therefore, it is necessary to research and develop a single-component polyurea anti-icing coating with excellent anti-icing performance and durability to meet the needs of all walks of life. Summary of the invention

[0004] The present invention aims to solve the problem that the existing polyurea coating cannot delay the freezing time and reduce the ice adhesion strength, and solve the problem that the two components of the two-component system coating need to be mixed before construction, and further provide a preparation method and use method of a single-component polyurea anti-icing coating.

[0005] A method for preparing a one-component polyurea anti-icing coating is carried out according to the following steps:

[0006] 1. Synthesis of silicon-containing prepolymer:

[0007] Under a nitrogen atmosphere and a temperature of 60° C. to 70° C., a diisocyanate compound is added dropwise to a hydroxyl-terminated polysiloxane, and after the addition is completed, the temperature is raised to 80° C. to 85° C., and the reaction is carried out at a temperature of 80° C. to 85° C. for 2 h to 3 h to obtain a silicon-containing prepolymer;

[0008] The mass ratio of the diisocyanate compound to the hydroxyl-terminated polysiloxane is 1:(4.2-7.7);

[0009] The general structural formula of the hydroxyl-terminated polysiloxane is HO-R-OH, wherein R is n is an integer greater than 1;

[0010] 2. Synthesis of silicon-modified latent curing agent:

[0011] Under the condition of nitrogen atmosphere and temperature of 20°C to 25°C, isobutyraldehyde and cyclohexane are magnetically stirred, and then amino-terminated polysiloxane is added dropwise, and acetic acid is added after the addition is completed, and the temperature is raised to 85°C to 90°C, and the reaction is carried out at a temperature of 85°C to 90°C for 6h to 12h, and finally the remaining isobutyraldehyde and cyclohexane are removed by rotary evaporation to obtain a silicon-modified latent curing agent;

[0012] The mass ratio of the amino-terminated polysiloxane to isobutylaldehyde is 1:(0.04-0.15); the mass ratio of the amino-terminated polysiloxane to cyclohexane is 1:(1-2);

[0013] The general structural formula of the amino-terminated polysiloxane is Where R2 is n is an integer greater than 1;

[0014] 3. Preparation of single-component polyurea anti-icing coating:

[0015] The silicon-containing prepolymer, the silicon-modified latent curing agent and the dimethyl silicone oil are stirred and mixed to obtain a single-component polyurea anti-icing coating;

[0016] The mass ratio of the silicon-containing prepolymer to the silicon-modified latent curing agent is 1:(0.8-1.2); the mass ratio of the silicon-containing prepolymer to the dimethyl silicone oil is 1:(0.5-0.8).

[0017] The beneficial effects of the present invention are:

[0018] The present invention provides a method for preparing a one-component polyurea anti-icing coating with excellent durability and a method for using the same. The coating preparation method is simple, the anti-icing performance and durability are excellent, the coating has great application value, and has the following advantages:

[0019] 1. Compared with two-component coatings that have a construction window period after mixing, single-component polyurea anti-icing coatings can be stored in a dry and cool place for at least three months. It does not need to be stirred before use and can be used at any time. The coating system is solvent-free and environmentally friendly.

[0020] 2. The surface contact angle of the single-component polyurea anti-icing coating is large (above 110°) and the rolling angle is small (below 6°), which allows water droplets to slide off the surface;

[0021] 3. Silicon-modified latent curing agent can not only reduce surface energy, but also the long silicon chain can enhance the lubrication between chain segments, further reducing ice adhesion strength;

[0022] 4. Excellent anti-icing performance, its surface ice adhesion strength (below 20kPa) is much lower than that of ordinary substrates;

[0023] 5. Compared with ordinary substrates, it can significantly delay the freezing time (below 290s);

[0024] 6. Excellent durability. After tests such as icing / de-icing cycle (below 26kPa), Taber wear (below 26kPa), acid and alkali (below 31kPa), and salt spray (below 30kPa), the ice adhesion strength is low.

[0025] The invention provides a preparation method and a use method of a single-component polyurea anti-icing coating. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 : is a reaction principle diagram of the present invention, (a) is the reaction of hydroxyl-terminated polysiloxane with diisocyanate compound in step 1 to generate silicon-containing prepolymer, (b) is the reaction of amino-terminated polysiloxane with isobutylaldehyde through Schiff base to obtain silicon-modified latent curing agent in step 2, (c) is the reaction of silicon-modified latent curing agent with water in air to obtain diamine in step 3, and (d) is the reaction of silicon-containing prepolymer with diamine to obtain single-component polyurea anti-icing coating;

[0027] Figure 2 This is a physical picture of the one-component polyurea anti-icing coating prepared in Example 1 after being stored for three months;

[0028] Figure 3 Comparison chart of the freezing delay time of the coating formed by the coatings stored for three months in Examples 1 to 2 and the substrates in Comparative Experiments 1 to 3;

[0029] Figure 4 This is a comparison chart of the ice adhesion strength of the coating formed by the coatings of Examples 1 to 2 stored for three months and the substrates of Comparative Experiments 1 to 3. DETAILED DESCRIPTION

[0030] The technical solution of the present invention is not limited to the specific implementation modes listed below, but also includes any combination of the specific implementation modes.

[0031] Specific implementation method 1: The preparation method of a one-component polyurea anti-icing coating described in this implementation method is carried out according to the following steps:

[0032] 1. Synthesis of silicon-containing prepolymer:

[0033] Under a nitrogen atmosphere and a temperature of 60° C. to 70° C., a diisocyanate compound is added dropwise to a hydroxyl-terminated polysiloxane, and after the addition is completed, the temperature is raised to 80° C. to 85° C., and the reaction is carried out at a temperature of 80° C. to 85° C. for 2 h to 3 h to obtain a silicon-containing prepolymer;

[0034] The mass ratio of the diisocyanate compound to the hydroxyl-terminated polysiloxane is 1:(4.2-7.7);

[0035] The general structural formula of the hydroxyl-terminated polysiloxane is HO-R-OH, wherein R is n is an integer greater than 1;

[0036] 2. Synthesis of silicon-modified latent curing agent:

[0037] Under the condition of nitrogen atmosphere and temperature of 20°C to 25°C, isobutyraldehyde and cyclohexane are magnetically stirred, and then amino-terminated polysiloxane is added dropwise, and acetic acid is added after the addition is completed, and the temperature is raised to 85°C to 90°C, and the reaction is carried out at a temperature of 85°C to 90°C for 6h to 12h, and finally the remaining isobutyraldehyde and cyclohexane are removed by rotary evaporation to obtain a silicon-modified latent curing agent;

[0038] The mass ratio of the amino-terminated polysiloxane to isobutylaldehyde is 1:(0.04-0.15); the mass ratio of the amino-terminated polysiloxane to cyclohexane is 1:(1-2);

[0039] The general structural formula of the amino-terminated polysiloxane is Where R2 is n is an integer greater than 1;

[0040] 3. Preparation of single-component polyurea anti-icing coating:

[0041] The silicon-containing prepolymer, the silicon-modified latent curing agent and the dimethyl silicone oil are stirred and mixed to obtain a single-component polyurea anti-icing coating;

[0042] The mass ratio of the silicon-containing prepolymer to the silicon-modified latent curing agent is 1:(0.8-1.2); the mass ratio of the silicon-containing prepolymer to the dimethyl silicone oil is 1:(0.5-0.8).

[0043] Figure 1 : is a reaction principle diagram of the present invention, (a) is the reaction of the hydroxyl-terminated polysiloxane with the diisocyanate compound in step 1 to generate a silicon-containing prepolymer, (b) is the reaction of the amino-terminated polysiloxane with isobutylaldehyde through Schiff base to obtain a silicon-modified latent curing agent in step 2, (c) is the reaction of the silicon-modified latent curing agent with water in the air in step 3 to obtain a diamine, and (d) is the reaction of the silicon-containing prepolymer with the diamine to obtain a single-component polyurea anti-icing coating; wherein R is n is an integer greater than 1; R1 is One or more of; R2 is n is an integer greater than 1; R3 is

[0044] This specific embodiment provides a method for preparing a one-component polyurea anti-icing coating and a method for using the same. The anti-icing coating is composed of an isocyanate-terminated silicon-containing prepolymer, a silicon-modified latent curing agent, and dimethyl silicone oil. Among them, the silicon-containing prepolymer is obtained by reacting a hydroxyl-terminated polysiloxane with a diisocyanate compound, and the silicon-modified latent curing agent is obtained by reacting an amino-terminated polysiloxane with an aldehyde through a Schiff base. The silicon-modified latent curing agent reacts with moisture in the air to obtain a diamine again, which then reacts with the isocyanate group in the silicon-containing prepolymer. After adding dimethyl silicone oil, a one-component polyurea anti-icing coating is obtained. The coating is stored in a dry and cool environment. The reaction principle is as follows: Figure 1 The one-component polyurea anti-icing coating can have excellent anti-icing performance after being simply coated and cured at room temperature, has strong durability, is easy to construct, and has broad application prospects.

[0045] The beneficial effects of this embodiment are:

[0046] This embodiment provides a method for preparing a one-component polyurea anti-icing coating with excellent durability and a method for using the same. The coating preparation method is simple, the anti-icing performance and durability are excellent, and the coating has great application value and has the following advantages:

[0047] 1. Compared with two-component coatings that have a construction window period after mixing, single-component polyurea anti-icing coatings can be stored in a dry and cool place for at least three months. It does not need to be stirred before use and can be used at any time. The coating system is solvent-free and environmentally friendly.

[0048] 2. The surface contact angle of the single-component polyurea anti-icing coating is large (above 110°) and the rolling angle is small (below 6°), which allows water droplets to slide off the surface;

[0049] 3. Silicon-modified latent curing agent can not only reduce surface energy, but also the long silicon chain can enhance the lubrication between chain segments, further reducing ice adhesion strength;

[0050] 4. Excellent anti-icing performance, its surface ice adhesion strength (below 20kPa) is much lower than that of ordinary substrates;

[0051] 5. Compared with ordinary substrates, it can significantly delay the freezing time (below 290s);

[0052] 6. Excellent durability. After tests such as icing / de-icing cycle (below 26kPa), Taber wear (below 26kPa), acid and alkali (below 31kPa), and salt spray (below 30kPa), the ice adhesion strength is low.

[0053] Specific embodiment 2: This embodiment is different from specific embodiment 1 in that the molecular weight of the hydroxyl-terminated polysiloxane described in step 1 is 1000 to 10000. Other aspects are the same as those of specific embodiment 1.

[0054] Specific embodiment 3: This embodiment is different from specific embodiment 1 or 2 in that the diisocyanate compound described in step 1 is one or a mixture of isophorone diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate and toluene diisocyanate. Others are the same as specific embodiment 1 or 2.

[0055] Specific embodiment 4: This embodiment differs from Specific embodiments 1 to 3 in that: in step 1, under a nitrogen atmosphere and a temperature of 60°C to 70°C, a diisocyanate compound is added dropwise to a hydroxyl-terminated polysiloxane at a dropping speed of 1 d / s to 2 d / s. The rest is the same as Specific embodiments 1 to 3.

[0056] Specific embodiment 5: This embodiment is different from specific embodiments 1 to 4 in that the molecular weight of the amino-terminated polysiloxane described in step 2 is 1000 to 3000. Other aspects are the same as specific embodiments 1 to 4.

[0057] Specific embodiment 6: This embodiment is different from specific embodiments 1 to 5 in that: in step 2, under the conditions of nitrogen atmosphere, temperature of 20°C to 25°C and stirring speed of 100rpm to 200rpm, isobutyraldehyde and cyclohexane are magnetically stirred for 10min to 30min, and then amino-terminated polysiloxane is added dropwise at a dropping speed of 1d / s to 2d / s. The rest is the same as specific embodiments 1 to 5.

[0058] Specific embodiment 7: This embodiment is different from Specific embodiments 1 to 6 in that the mass ratio of the amino-terminated polysiloxane to acetic acid in step 2 is 1:(0.001-0.002). Others are the same as Specific embodiments 1 to 6.

[0059] Specific embodiment 8: This embodiment differs from specific embodiments 1 to 7 in that: in step 3, the silicon-containing prepolymer, silicon-modified latent curing agent and dimethyl silicone oil are stirred and mixed for 5 to 10 minutes at a stirring speed of 600 to 1000 rpm. The rest is the same as specific embodiments 1 to 7.

[0060] Specific embodiment nine: This embodiment provides a method for using a one-component polyurea anti-icing coating, which is carried out according to the following steps: spray or brush the one-component polyurea anti-icing coating onto the surface of the substrate, and cure it at room temperature for 1h to 12h to obtain a one-component polyurea anti-icing coating.

[0061] Specific embodiment 10: This embodiment differs from specific embodiment 9 in that the thickness of the single-component polyurea anti-icing coating is 100 μm to 150 μm. Other aspects are the same as specific embodiment 9.

[0062] The following examples are used to verify the beneficial effects of the present invention:

[0063] Embodiment 1:

[0064] A method for preparing a one-component polyurea anti-icing coating is carried out according to the following steps:

[0065] 1. Synthesis of silicon-containing prepolymer:

[0066] Under the conditions of nitrogen atmosphere and temperature of 60° C., 5 g of diisocyanate compound was added dropwise to 21.4 g of hydroxyl-terminated polysiloxane at a dropping speed of 1 d / s. After the addition was completed, the temperature was raised to 80° C., and the reaction was carried out at a temperature of 80° C. for 2 h to obtain a silicon-containing prepolymer;

[0067] The structural formula of the hydroxyl-terminated polysiloxane is HO-R-OH, wherein R is n is an integer greater than 1;

[0068] 2. Synthesis of silicon-modified latent curing agent:

[0069] Under the conditions of nitrogen atmosphere, temperature of 25°C and stirring speed of 100 rpm, 7.2 g of isobutylaldehyde and 120 g of cyclohexane were magnetically stirred for 10 min, and then 100 g of amino-terminated polysiloxane was added dropwise at a dropping speed of 1 d / s. After the addition was completed, 0.1 g of acetic acid was added, and the temperature was raised to 85°C. Under the condition of temperature of 85°C, the reaction was carried out for 6 h, and finally the remaining isobutylaldehyde and cyclohexane were removed by rotary evaporation to obtain a silicon-modified latent curing agent;

[0070] The structural formula of the amino-terminated polysiloxane is Where R2 is n is an integer greater than 1;

[0071] 3. Preparation of single-component polyurea anti-icing coating:

[0072] Under the condition of a stirring speed of 800 rpm, 2 g of silicon-containing prepolymer, 2 g of silicon-modified latent curing agent and 1 g of dimethyl silicone oil were stirred and mixed for 10 minutes to obtain a single-component polyurea anti-icing coating.

[0073] The hydroxyl-terminated polysiloxane described in step 1 has a molecular weight of 5000 and is purchased from Gelest Company with a model number of DMS-C21.

[0074] The diisocyanate compound described in step 1 is diphenylmethane diisocyanate.

[0075] The amino-terminated polysiloxane described in step 2 has a molecular weight of 1000 and is purchased from Gelest Company with a model number of DMS-A12.

[0076] The one-component polyurea anti-icing coating prepared in Example 1 was stored in a dry and cool place for 3 months, and then the one-component polyurea anti-icing coating stored for 3 months was sprayed onto the surface of the aluminum plate and cured at room temperature for 4 hours to obtain a one-component polyurea anti-icing coating, wherein the thickness of the one-component polyurea anti-icing coating was 150 μm; and then the following performance tests were performed:

[0077] The contact angle and rolling angle of the anti-icing coating of Example 1 were tested using an OCA20 video optical contact angle meter, and the test results were 114.2° and 5.6°, respectively.

[0078] Under the condition of an ambient temperature of -10°C, the freezing time of a 5 μL water droplet on the anti-icing coating of Example 1 is 290 s.

[0079] The following test methods for ice adhesion strength are all tested according to the following process: ① Place the anti-icing coating on a semiconductor refrigeration plate, cool it to -15℃, and control the humidity to 60±5%. Then, place an open mold with a size of 10*10*10mm on the surface of the coating, and add 1mL of water to the mold. After freezing for 2 hours under the conditions of ambient temperature of -15℃ and humidity of 60%, remove the ice from the shear direction under the action of a shear force of 0.8mm / s, and record the reading F on the force sensor. The value of ice adhesion strength is the ratio of F to the ice area; ② Repeat according to ① when repeating the icing / deicing cycle.

[0080] The ice adhesion strength on the surface of the anti-icing coating of Example 1 is 19.3 kPa.

[0081] After 50 icing / deicing cycles, the ice adhesion strength of the anti-icing coating of Example 1 was 25.1 kPa.

[0082] The wear resistance of the anti-icing coating of Example 1 was tested using a Taber abrasion tester, with a load of 250 g and a grinding wheel model of CS-10. After 5000 Taber abrasions, the ice adhesion strength of the anti-icing coating of Example 1 was 25.6 kPa.

[0083] A hydrochloric acid solution with a concentration of 1 mol / L and a sodium hydroxide solution with a concentration of 1 mol / L were prepared respectively. The anti-icing coating of Example 1 was immersed in the two solutions for 72 hours and then taken out. The ice adhesion strengths were 30.1 kPa and 25.2 kPa respectively.

[0084] The salt spray resistance of the anti-icing coating of Example 1 was tested according to GB / T 10125-2012. The test conditions were neutral salt spray, the test temperature was 35° C., the test time was 240 h, and the ice adhesion strength after the test was 29.6 kPa.

[0085] Embodiment 2:

[0086] A method for preparing a one-component polyurea anti-icing coating is carried out according to the following steps:

[0087] 1. Synthesis of silicon-containing prepolymer:

[0088] Under the conditions of nitrogen atmosphere and temperature of 70°C, 4.5 g of diisocyanate compound was added dropwise to 22.2 g of hydroxyl-terminated polysiloxane at a dropping speed of 2 d / s. After the addition was completed, the temperature was raised to 85°C, and the reaction was carried out at a temperature of 85°C for 2 hours to obtain a silicon-containing prepolymer;

[0089] The structural formula of the hydroxyl-terminated polysiloxane is HO-R-OH, wherein R is n is an integer greater than 1;

[0090] 2. Synthesis of silicon-modified latent curing agent:

[0091] Under the conditions of nitrogen atmosphere, temperature of 25°C and stirring speed of 200 rpm, 7.2 g of isobutylaldehyde and 240 g of cyclohexane were magnetically stirred for 15 min, and then 150 g of amino-terminated polysiloxane was added dropwise at a dropping speed of 2 d / s, and 0.3 g of acetic acid was added after the addition was completed, and the temperature was raised to 90°C. The reaction was carried out at a temperature of 90°C for 10 h, and finally the remaining isobutylaldehyde and cyclohexane were removed by rotary evaporation to obtain a silicon-modified latent curing agent;

[0092] The structural formula of the amino-terminated polysiloxane is Where R2 is n is an integer greater than 1;

[0093] 3. Preparation of single-component polyurea anti-icing coating:

[0094] Under the condition of a stirring speed of 1000 rpm, 2 g of silicon-containing prepolymer, 2.4 g of silicon-modified latent curing agent and 1.2 g of dimethyl silicone oil were stirred and mixed for 10 minutes to obtain a single-component polyurea anti-icing coating.

[0095] The hydroxyl-terminated polysiloxane described in step 1 has a molecular weight of 1000 and is purchased from Gelest Company with a model number of DMS-C15.

[0096] The diisocyanate compound described in step 1 is isophorone diisocyanate.

[0097] The amino-terminated polysiloxane described in step 2 has a molecular weight of 3000 and is purchased from Gelest Company with a model number of DMS-A15.

[0098] The one-component polyurea anti-icing coating prepared in Example 2 was stored in a dry and cool place for 3 months, and then the one-component polyurea anti-icing coating stored for 3 months was sprayed onto the surface of the aluminum plate and cured at room temperature for 6 hours to obtain a one-component polyurea anti-icing coating, wherein the thickness of the one-component polyurea anti-icing coating was 150 μm; and then the following performance tests were performed:

[0099] The contact angle and rolling angle of the anti-icing coating of Example 2 were tested using an OCA20 video optical contact angle meter, and the test results were 112.4° and 4.6°, respectively.

[0100] Under the condition of an ambient temperature of -10°C, the freezing time of a 5 μL water droplet on the anti-icing coating of Example 2 is 286 s.

[0101] The following test methods for ice adhesion strength are all tested according to the following process: ① Place the anti-icing coating on a semiconductor refrigeration plate, cool it to -15℃, and control the humidity to 60±5%. Then, place an open mold with a size of 10*10*10mm on the surface of the coating, and add 1mL of water to the mold. Under the conditions of ambient temperature of -15℃ and humidity of 60%, freeze it for 1h, and then remove the ice from the shear direction under the action of a shear force of 0.8mm / s, and record the reading F on the force sensor. The value of ice adhesion strength is the ratio of F to the ice area; ② Repeat according to ① when repeating the icing / deicing cycle.

[0102] The ice adhesion strength on the surface of the anti-icing coating of Example 2 is 18.2 kPa.

[0103] After 50 icing / deicing cycles, the ice adhesion strength of the anti-icing coating of Example 2 was 23.2 kPa.

[0104] The wear resistance of the anti-icing coating of Example 2 was tested using a Taber abrasion tester, with a load of 250 g and a grinding wheel model of CS-10. After 5000 Taber abrasions, the ice adhesion strength of the anti-icing coating of Example 2 was 24.2 kPa.

[0105] A hydrochloric acid solution with a concentration of 1 mol / L and a sodium hydroxide solution with a concentration of 1 mol / L were prepared respectively. The anti-icing coating of Example 2 was immersed in the two solutions for 72 hours and then taken out. The ice adhesion strengths were 28.2 kPa and 27.4 kPa respectively.

[0106] The salt spray resistance of the anti-icing coating of Example 2 was tested according to GB / T 10125-2012. The test conditions were neutral salt spray, the test temperature was 35° C., the test time was 240 h, and the ice adhesion strength after the test was 26.4 kPa.

[0107] Comparative Example 1:

[0108] The aluminum sheet was used as the substrate and the surface was cleaned with ethanol before testing. Under the condition of an ambient temperature of -10°C, the freezing time of a 5 μL water droplet on the aluminum sheet of Comparative Example 1 was 8s. Under the condition of an ambient temperature of -15°C, after the aluminum sheet of Comparative Example 1 was frozen for 12h, the ice adhesion strength on the surface of the aluminum sheet was tested to be 815.5 kPa. The testing method is the same as that of Example 1.

[0109] Comparative Example 2:

[0110] Using glass as the substrate, the surface was cleaned with ethanol before testing. Under the condition of an ambient temperature of -10°C, the freezing time of a 5μL water droplet on the glass of Comparative Example 2 was 11s. Under the condition of an ambient temperature of -15°C, after the glass of Comparative Example 2 was frozen for 12h, the ice adhesion strength on the surface of the tested glass was 522.1kPa. The testing method is the same as that of Example 1.

[0111] Comparative Example 3:

[0112] Sylgard 184 was used as the substrate and the curing condition was 80°C for 4 hours. Under the condition of an ambient temperature of -10°C, the freezing time of a 5 μL water droplet on Sylgard 184 of Comparative Example 3 was 72 seconds. Under the condition of an ambient temperature of -15°C, after the Sylgard 184 of Comparative Example 3 was frozen for 12 hours, the ice adhesion strength of the surface of Sylgard 184 was tested to be 188.2 kPa. The test method is the same as that of Example 1.

[0113] Figure 2 This is a real picture of the one-component polyurea anti-icing coating prepared in Example 1 after being stored for three months; as can be seen from the figure, no obvious stratification is found.

[0114] Figure 3 Comparison chart of the freezing delay time of the coating formed by the coatings stored for three months in Examples 1 to 2 and the substrates in Comparative Experiments 1 to 3; Figure 4 The following is a comparison chart of the surface ice adhesion strength of the coating formed by the coating stored for three months in Examples 1 to 2 and the substrate of Comparative Experiments 1 to 3. It can be seen from Comparative Examples 1-3 that the substrate not coated with the anti-icing coating of Examples 1 to 2 has a shorter surface freezing delay time and a higher ice adhesion strength.

[0115] Table 1 Performance Test of Examples 1 and 2

[0116]

[0117]

Claims

1. A method for preparing a one-component polyurea anti-icing coating, characterized in that It is carried out according to the following steps:

1. Synthesis of silicon-containing prepolymer: Under the conditions of nitrogen atmosphere and temperature of 60°C to 70°C, a diisocyanate compound is added dropwise to a hydroxyl-terminated polysiloxane at a dropping speed of 1d / s to 2d / s, and after the addition is completed, the temperature is raised to 80°C to 85°C, and the reaction is carried out at a temperature of 80°C to 85°C for 2h to 3h to obtain a silicon-containing prepolymer; The mass ratio of the diisocyanate compound to the hydroxyl-terminated polysiloxane is 1:(4.2-7.7); The general structural formula of the hydroxyl-terminated polysiloxane is HO-R-OH, wherein R is n is an integer greater than 1; The molecular weight of the hydroxyl-terminated polysiloxane is 1000 to 10000; 2. Synthesis of silicon-modified latent curing agent: Under the conditions of nitrogen atmosphere, temperature of 20°C to 25°C and stirring speed of 100rpm to 200rpm, isobutyraldehyde and cyclohexane are magnetically stirred for 10min to 30min, then amino-terminated polysiloxane is added dropwise at a dropping speed of 1d / s to 2d / s, acetic acid is added after the addition is completed, and the temperature is raised to 85°C to 90°C, and the reaction is carried out at a temperature of 85°C to 90°C for 6h to 12h, and finally the remaining isobutyraldehyde and cyclohexane are removed by rotary evaporation to obtain a silicon-modified latent curing agent; The mass ratio of the amino-terminated polysiloxane to isobutylaldehyde is 1:(0.04-0.15); the mass ratio of the amino-terminated polysiloxane to cyclohexane is 1:(1-2); the mass ratio of the amino-terminated polysiloxane to acetic acid is 1:(0.001-0.002); The general structural formula of the amino-terminated polysiloxane is Where R2 is n is an integer greater than 1; The molecular weight of the amino-terminated polysiloxane is 1000 to 3000; 3. Preparation of single-component polyurea anti-icing coating: The silicon-containing prepolymer, the silicon-modified latent curing agent and the dimethyl silicone oil are stirred and mixed to obtain a single-component polyurea anti-icing coating; The mass ratio of the silicon-containing prepolymer to the silicon-modified latent curing agent is 1:(0.8-1.2); the mass ratio of the silicon-containing prepolymer to the dimethyl silicone oil is 1:(0.5-0.8).

2. The method for preparing a one-component polyurea anti-icing coating according to claim 1, characterized in that The diisocyanate compound described in step 1 is one of isophorone diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate and toluene diisocyanate, or a mixture of several of them.

3. The method for preparing a one-component polyurea anti-icing coating according to claim 1, characterized in that In step 3, the silicon-containing prepolymer, the silicon-modified latent curing agent and the dimethyl silicone oil are stirred and mixed for 5 minutes to 10 minutes at a stirring speed of 600 rpm to 1000 rpm.

4. The method for using a one-component polyurea anti-icing coating according to claim 1, characterized in that The method is carried out according to the following steps: spraying or brushing a single-component polyurea anti-icing coating onto a substrate surface, and curing the coating at room temperature for 1 hour to 12 hours to obtain the single-component polyurea anti-icing coating.

5. The method for using a one-component polyurea anti-icing coating according to claim 4, characterized in that The thickness of the single-component polyurea anti-icing coating is 100 μm to 150 μm.

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