Anti-icing paint, coating and preparation method thereof

Abstract

The invention provides an anti-icing coating as well as a coating and a preparation method thereof, and relates to the technical field of functional materials. According to the invention, raw materials such as methylated melamine formaldehyde resin, hexamethylene diisocyanate tripolymer, isophorone diisocyanate, polydimethylsiloxane, polypropylene carbonate glycol and the like are adopted to react with one another to form a polymer, so that a low-surface-energy liquid-like smooth surface is formed. The polydimethylsiloxane is used as an auxiliary agent with low surface energy and can be enriched on the surface to form a compact molecular brush; poly (propylene carbonate) glycol and polytetrahydrofuran are used as soft segments of a polymer and provide low elastic modulus; and the molecular brush and the soft section play a role together, so that the coating has excellent anti-icing performance. The anti-icing paint and the coating thereof are simple to prepare and low in cost, and have excellent stability and very high application value.

Description

Technical Field

[0001] The present invention relates to the technical field of functional materials, and in particular to an anti-icing coating and a coating and a preparation method thereof. Background Art

[0002] Icing is a common phenomenon in nature. Icing on the surfaces of wind turbine blades, transmission lines, aircraft wings, communication equipment, etc. can cause great harm to the economy and personal safety. Therefore, reducing or avoiding icing is of great significance to production and life.

[0003] Traditional deicing methods include electrothermal deicing (this method converts electrical energy into thermal energy to increase the temperature to achieve the purpose of deicing), mechanical deicing (using manual or mechanical equipment to remove ice attached to the surface of an object), and chemical deicing (by spraying chemical reagents on the surface to lower the freezing point, thereby achieving the purpose of deicing). However, these methods generally have problems such as high energy consumption, low deicing efficiency, and environmental pollution, so it is very necessary to develop anti-icing coatings.

[0004] Wherein super hydrophobic coating (such as CN116836593A, CN114220617B, CN115637131B) is the most commonly used anti-icing coating at present, and super hydrophobic coating has higher water contact angle and lower water sliding angle, and water droplets can be removed on the surface before freezing, so as to prevent the formation of ice. Simultaneously, because super hydrophobic surface has micro-nano structure, a large amount of air pockets are captured, and these air pockets can significantly reduce the contact area between droplet and surface, and play the role of thermal insulation layer, so that freezing time is extended. In addition, these air pockets act as stress concentration points in freezing process, so that ice cube can be removed under the effect of less thrust. But as time goes by, small ice crystals may appear in the micro-nano structure of super hydrophobic coating, and these small ice crystals gradually converge into large ice crystals, and large ice crystals are combined with external ice cubes, causing mechanical interlocking to occur between ice cubes and micro-nano structure, so that the adhesion strength of ice rises.

[0005] As the research deepened, liquid-like smooth surfaces were proposed. This type of coating grafts low surface energy polymers onto the surface, giving the surface liquid-like properties. This type of coating has a higher water contact angle and a lower water sliding angle, so water droplets can be removed before freezing. Moreover, due to the presence of the low surface energy polymer layer, the coating has a lower ice adhesion strength. In addition, there will be no mechanical interlocking between ice cubes and the coating in liquid-like anti-icing coatings; at the same time, since the low surface energy polymer layer is grafted onto the surface through covalent bonds, the coating has excellent mechanical stability. However, there are relatively few reports on related liquid-like smooth anti-icing coatings. Therefore, the development of a liquid-like smooth anti-icing coating has high application value. Summary of the invention

[0006] In view of the defects in the prior art, the object of the present invention is to provide an anti-icing coating and a coating and a preparation method thereof.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] In a first aspect, the present invention provides an anti-icing coating, wherein the raw materials include, by weight: 1 to 50 parts of polydimethylsiloxane, 100 to 500 parts of polypropylene carbonate diol, 500 to 1500 parts of solvent, 5 to 30 parts of p-toluenesulfonic acid, 100 to 600 parts of methyl etherified melamine formaldehyde resin, 100 to 500 parts of hexamethylene diisocyanate trimer, 100 to 300 parts of isophorone diisocyanate, and 100 to 500 parts of polytetrahydrofuran.

[0009] Furthermore, the solvent is a mixture of propylene glycol methyl ether acetate and N,N-dimethylformamide.

[0010] Furthermore, the relative molecular mass of the polydimethylsiloxane is preferably 2000-10000.

[0011] Furthermore, the relative molecular mass of the polypropylene carbonate diol is preferably 1000-5000.

[0012] Furthermore, the relative molecular mass of the polytetrahydrofuran is preferably 1000-5000.

[0013] In a second aspect, the present invention provides a method for preparing an anti-icing coating, comprising the following steps:

[0014] Step 100, reacting hexamethylene diisocyanate trimer, isophorone diisocyanate and polydimethylsiloxane at 80-100° C. for 1-5 hours;

[0015] Step 101, dissolving the substance obtained in step 100 in a solvent, and stirring to obtain a solution;

[0016] Step 102, adding polypropylene carbonate diol and polytetrahydrofuran to the solution obtained in step 101, and reacting at 80-100° C. for 1-5 hours;

[0017] Step 103, adding methyl etherified melamine formaldehyde resin and p-toluenesulfonic acid to the solution obtained in step 102, stirring evenly, to obtain the anti-icing coating.

[0018] In a third aspect, the present invention provides an anti-icing coating formed by the anti-icing paint, which has a liquid-like smooth surface.

[0019] In a fourth aspect, the present invention provides a method for preparing an anti-icing coating, comprising the following steps:

[0020] Step 200, applying an anti-icing coating on the surface of the substrate by brushing or spraying;

[0021] Step 201, curing to obtain the anti-icing coating.

[0022] Furthermore, the substrate is glass, ceramic, metal, plastic or wood.

[0023] Furthermore, in step 201, the curing conditions are: the curing temperature is 100-150°C, and the curing time is 0.5-3h.

[0024] The technical solution of the present invention has the following advantages:

[0025] The present invention adopts raw materials such as methyl etherified melamine formaldehyde resin, hexamethylene diisocyanate trimer, isophorone diisocyanate, polydimethylsiloxane, polypropylene carbonate diol, etc., and forms a polymer through mutual reaction, which is coated on the surface of the substrate to form a low surface energy liquid-like smooth surface coating. Among them, the methyl etherified melamine formaldehyde resin provides many binding sites to form a highly cross-linked polymer; polydimethylsiloxane is a low surface energy auxiliary agent, which is enriched on the surface during the cross-linking and curing process to form a dense molecular brush; polypropylene carbonate diol and polytetrahydrofuran are the soft segments of the polymer, providing a lower elastic modulus; the molecular brush and the soft segment work together to make the coating have both excellent anti-icing performance and excellent liquid repellency.

[0026] The anti-icing paint and coating of the present invention have stable performance, simple preparation method and low cost, and can be coated on the surface of substrates such as glass, stainless steel, and polymer materials by brushing, spraying, etc., so that it has relatively excellent anti-icing performance and has high application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 It is a schematic diagram comparing the freezing time of an anti-icing coating formed by applying the anti-icing coating provided by an embodiment of the present invention on a glass sheet and a blank sample without coating. DETAILED DESCRIPTION

[0029] The following examples are provided for a better understanding of the present invention, but are not intended to limit the best mode of implementation, nor to limit the content and protection scope of the present invention. Any product identical or similar to the present invention obtained by anyone under the inspiration of the present invention or by combining the features of the present invention with other prior arts shall fall within the protection scope of the present invention.

[0030] If no specific experimental steps or conditions are specified in the examples, the conventional experimental steps or conditions described in the literature in the art can be used. The raw materials or instruments used are all conventional products that can be obtained commercially, including but not limited to the raw materials or instruments used in the examples of this application.

[0031] An anti-icing coating, a coating layer and a preparation method thereof provided in an embodiment of the present invention will be described in detail below in conjunction with the accompanying drawings.

[0032] Example 1

[0033] The present embodiment provides an anti-icing coating, and the raw materials include, by weight: 2 parts of polydimethylsiloxane, 150 parts of polypropylene carbonate diol, 600 parts of a mixed solvent of propylene glycol methyl ether acetate and N,N-dimethylformamide, 8 parts of p-toluenesulfonic acid, 350 parts of methyl etherified melamine formaldehyde resin, 150 parts of hexamethylene diisocyanate trimer, 200 parts of isophorone diisocyanate, and 100 parts of polytetrahydrofuran.

[0034] In this embodiment, the method for preparing the anti-icing coating comprises the following steps:

[0035] Step 100, reacting hexamethylene diisocyanate trimer, isophorone diisocyanate and polydimethylsiloxane at 80° C. for 1 hour;

[0036] Step 101, dissolving the substance obtained in step 100 in a solvent, and stirring to obtain a solution;

[0037] Step 102: adding polypropylene carbonate diol and polytetrahydrofuran to the solution obtained in step 101, and reacting at 80° C. for 1 hour.

[0038] Step 103, adding methyl etherified melamine formaldehyde resin and p-toluenesulfonic acid to the solution obtained in step 102, stirring evenly, to obtain the anti-icing coating.

[0039] Example 2

[0040] The present embodiment provides an anti-icing coating, and the raw materials include, by weight: 2 parts of polydimethylsiloxane, 250 parts of polypropylene carbonate diol, 600 parts of a mixed liquid solvent of propylene glycol methyl ether acetate and N,N-dimethylformamide, 15 parts of p-toluenesulfonic acid, 350 parts of methyl etherified melamine formaldehyde resin, 200 parts of hexamethylene diisocyanate trimer, 150 parts of isophorone diisocyanate, and 125 parts of polytetrahydrofuran.

[0041] In this embodiment, the preparation method of the anti-icing coating can refer to Example 1, except that in step 100 and step 102, the reaction temperature is 90° C. and the reaction time is 1 hour respectively.

[0042] Example 3

[0043] The present embodiment provides an anti-icing coating, and the raw materials include, by weight: 50 parts of polydimethylsiloxane, 250 parts of polypropylene carbonate glycol, 1000 parts of a mixed solvent of propylene glycol methyl ether acetate and N,N-dimethylformamide, 20 parts of p-toluenesulfonic acid, 600 parts of methyl etherified melamine formaldehyde resin, 500 parts of hexamethylene diisocyanate trimer, 150 parts of isophorone diisocyanate, and 150 parts of polytetrahydrofuran.

[0044] In this embodiment, the preparation method of the anti-icing coating can refer to Example 1, except that in step 100 and step 102, the reaction temperature is 90° C. and the reaction time is 2 hours.

[0045] Example 4

[0046] The present embodiment provides an anti-icing coating, and the raw materials include, by weight: 7 parts of polydimethylsiloxane, 400 parts of polypropylene carbonate glycol, 700 parts of a mixed solvent of propylene glycol methyl ether acetate and N,N-dimethylformamide, 16 parts of p-toluenesulfonic acid, 300 parts of methyl etherified melamine formaldehyde resin, 300 parts of hexamethylene diisocyanate trimer, 175 parts of isophorone diisocyanate, and 250 parts of polytetrahydrofuran.

[0047] In this embodiment, the preparation method of the anti-icing coating can refer to Example 1, except that in step 100, the reaction temperature is 85°C and the reaction time is 2 hours, and in step 102, the reaction temperature is 90°C and the reaction time is 2 hours.

[0048] Example 5

[0049] The present embodiment provides an anti-icing coating, and the raw materials include, by weight: 9 parts of polydimethylsiloxane, 250 parts of polypropylene carbonate glycol, 900 parts of a mixed liquid solvent of propylene glycol methyl ether acetate and N,N-dimethylformamide, 10 parts of p-toluenesulfonic acid, 350 parts of methyl etherified melamine formaldehyde resin, 130 parts of hexamethylene diisocyanate trimer, 125 parts of isophorone diisocyanate, and 300 parts of polytetrahydrofuran.

[0050] In this embodiment, the preparation method of the anti-icing coating can refer to Example 1, except that in step 100, the reaction temperature is 85°C and the reaction time is 2 hours, and in step 102, the reaction temperature is 95°C and the reaction time is 2 hours.

[0051] Anti-icing test example 1

[0052] The ice adhesion performance test was performed on the anti-icing coatings prepared in Examples 1 to 5 of the present invention.

[0053] Preparation before the test:

[0054] (1) The anti-icing coatings prepared in Examples 1 to 5 were respectively applied on glass sheets and cured at 100° C. for 1 h.

[0055] (2) No treatment is performed on the blank glass.

[0056] Ice adhesion strength test:

[0057] Using the anti-icing equipment built in the laboratory, a polyvinyl chloride tube with a diameter of 10 mm was placed on the test sample. After precooling at -10℃ for 5 minutes, a 1 cm high water column was injected into the polyvinyl chloride tube and kept at -10℃ for 1 hour. The polyvinyl chloride tube was pushed at a speed of 10 mm / min with a push-pull dynamometer until obvious displacement occurred between the polyvinyl chloride tube and the test sample. The required maximum force was obtained, and the ice adhesion strength was calculated according to τ=F / S.

[0058] The test results are shown in Table 1.

[0059] Table 1 Test results of ice adhesion strength performance of test samples coated with the anti-icing coatings prepared in Examples 1 to 5 and uncoated control samples

[0060]

[0061] Anti-icing test example 2

[0062] The anti-icing coatings prepared in Examples 1 to 5 of the present invention were tested for their performance in extending the freezing time.

[0063] Preparation before the test:

[0064] (1) The anti-icing coatings prepared in Examples 1 to 5 were respectively applied on glass sheets and cured at 100° C. for 1 h.

[0065] (2) No treatment is performed on the blank glass.

[0066] Extended freezing time test:

[0067] The test sample was placed at -10°C, and then 100 μL of deionized water was added dropwise to the uncoated blank sample and the test sample coated with the anti-icing coating prepared in Examples 1 to 5, respectively, and the time required for the water drop to completely freeze was measured.

[0068] The test results are shown in Table 2.

[0069] Table 2 Test results of water drop freezing time of the test samples coated with the anti-icing coatings prepared in Examples 1 to 5 and the control samples without coating

[0070]

[0071]

[0072] like Figure 1 As shown, 100 μL of deionized water was added to the test sample coated with the anti-icing coating prepared in Example 1 and the uncoated blank sample. After maintaining the temperature at -10°C for 60 seconds, the water droplets on the uncoated blank sample were completely frozen, while the deionized water droplets on the coated test sample were not completely frozen until 200 seconds. This shows that the anti-icing coating and its coating of the present invention have excellent ability to delay freezing.

[0073] In summary, the present invention uses methyl etherified melamine formaldehyde resin, hexamethylene diisocyanate trimer, isophorone diisocyanate, polydimethylsiloxane, polypropylene carbonate diol and other raw materials to form a polymer through mutual reaction, which is coated on the surface of the substrate to form a low surface energy liquid-like smooth surface coating. Among them, the methyl etherified melamine formaldehyde resin provides many binding sites to form a highly cross-linked polymer; polydimethylsiloxane is a low surface energy auxiliary agent, which is enriched on the surface during the cross-linking and curing process to form a dense molecular brush; polypropylene carbonate diol and polytetrahydrofuran are the soft segments of the polymer, providing a lower elastic modulus; the molecular brush and the soft segment work together to make the coating have both excellent anti-icing performance and excellent liquid repellency.

[0074] The present invention also conducted a water drop freezing time test and a water drop freezing time test, using a glass sheet coated with the anti-icing coating provided by the embodiment of the present invention as a test sample and a blank glass without coating as a control sample. The raw material ratio of the anti-icing coating provided by the embodiment of the present invention and the test results of the coating and the uncoated control are shown in Table 3.

[0075] Combination Figure 1 As shown, at a temperature of -10°C, the water droplets on the uncoated blank sample completely freeze after 60 seconds, while the water droplets on the coated test sample are not completely frozen until 200 seconds. It can be seen that the anti-icing coating of the present invention can be applied to the surface of glass, stainless steel, polymer materials and other substrates by brushing, spraying and other methods to form a low surface energy liquid-like smooth surface coating, so that it has relatively excellent anti-icing performance and has high application value.

[0076] Table 3 Raw material ratios of the anti-icing coatings provided in Examples 1 to 5 and test results of ice adhesion strength and water drop freezing time of the coatings and the uncoated controls

[0077]

[0078] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. An anti-icing coating, characterized in that: The raw materials include, by weight: 1-50 parts of polydimethylsiloxane, 100-500 parts of polypropylene carbonate diol, 500-1500 parts of solvent, 5-30 parts of p-toluenesulfonic acid, 100-600 parts of methyl etherified melamine formaldehyde resin, 100-500 parts of hexamethylene diisocyanate trimer, 100-300 parts of isophorone diisocyanate and 100-500 parts of polytetrahydrofuran.

2. The anti-icing coating according to claim 1, characterized in that: The solvent is a mixed solution of propylene glycol methyl ether acetate and N,N-dimethylformamide.

3. The anti-icing coating according to claim 1, characterized in that: The relative molecular mass of the polydimethylsiloxane is 2000-10000, the relative molecular mass of the polypropylene carbonate diol is 1000-5000, and the relative molecular mass of the polytetrahydrofuran is 1000-5000.

4. The method for preparing the anti-icing coating according to any one of claims 1 to 3, characterized in that: The following steps are involved: Step 100, reacting hexamethylene diisocyanate trimer, isophorone diisocyanate and polydimethylsiloxane at 80-100° C. for 1-5 hours; Step 101, dissolving the substance obtained in step 100 in a solvent, and stirring to obtain a solution; Step 102, adding polypropylene carbonate diol and polytetrahydrofuran to the solution obtained in step 101, and reacting at 80-100° C. for 1-5 hours; Step 103, adding methyl etherified melamine formaldehyde resin and p-toluenesulfonic acid to the solution obtained in step 102, stirring evenly, to obtain the anti-icing coating.

5. An anti-icing coating, characterized in that: The anti-icing coating is formed by any one of claims 1 to 4, wherein the coating has a liquid-like smooth surface.

6. The method for preparing the anti-icing coating according to claim 5, characterized in that: The following steps are involved: Step 200, applying the anti-icing coating according to any one of claims 1 to 4 on the surface of the substrate by brushing or spraying; Step 201, curing to obtain the anti-icing coating.

7. The method for preparing the anti-icing coating according to claim 6, characterized in that: The substrate is glass, ceramic, metal, plastic or wood.

8. The method for preparing the anti-icing coating according to claim 6, characterized in that: In step 201, the curing conditions are: curing temperature is 100-150°C, and curing time is 0.5-3h.

Images