High-temperature-resistant and high-humidity-resistant antifouling coating and manufacturing method thereof

Abstract

The invention discloses a high-temperature-resistant and high-humidity-resistant antifouling coating and a manufacturing method thereof, and relates to the related technical field of high polymer materials. Ester compounds are grafted to a hydrogen-containing silicone oil side chain mainly through the coordination addition reaction of silicon-hydrogen bonds and double bonds, and crystalline polysiloxane-based polyhydric alcohol is synthesized; the anti-fouling agent is used for polyurethane synthesis, and a coating with excellent anti-fouling capacity is prepared. The prepared anti-fouling coating has the following advantages that in the using process, a chain segment is driven to selectively migrate towards a surface layer and a bottom layer in a balanced mode through surface energy, a compact cross-linked network can be formed on the surface of the coating, crystals can be formed on the basis of polyester chain segments, the anti-fouling property and the base material adhesion of the anti-fouling coating are higher than those of a common anti-fouling coating, and the service life of the anti-fouling coating is prolonged. The antifouling property can be maintained for a long time in a high-temperature and high-humidity environment.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer materials, and specifically relates to an anti-fouling coating resistant to high temperature and high humidity and a manufacturing method thereof. Background Art

[0002] The adhesion phenomenon of liquids on various surfaces is a common physical process in human activities. However, in fields such as anti-fouling, self-cleaning, and drag reduction, liquid adhesion can cause adverse effects. In practical scenarios such as the drag reduction transportation of crude oil, metal anti-corrosion, oil-water separation, self-cleaning of equipment, and drag reduction of waterborne vehicles, the most economical and effective method at present is to coat an anti-fouling coating. The commonly used methods for preparing anti-fouling coatings can be divided into three categories. The first category is superhydrophobic / superamphiphobic surfaces, which consist of low surface energy chemical elements and composite micro-nano rough structures and have superliquidophobic capabilities. However, due to their complex micro-nano fractal structures being very fragile, they are easily deformed and damaged under external forces, thus losing their superliquidophobic properties. The second category is liquid-infused smooth porous surfaces, which prevent liquid attachment through a smooth surface and lubricants and have excellent anti-liquid adhesion capabilities. However, the lubricants are prone to loss during use, resulting in a significant decline in the anti-liquid adhesion capabilities. The third category is monolayer anti-fouling coatings, which form a (polymer) monolayer on the substrate surface by grafting low surface energy segments to achieve the anti-fouling effect. The preparation of the monolayer generally requires pretreatment of the substrate surface. In addition, its wear resistance is insufficient and it is easily lose its anti-fouling performance in a friction environment. The above anti-fouling coatings have problems such as complex construction processes, difficulty in engineering magnification, and easy destruction of the structure during application, resulting in a decline or even failure of the anti-fouling performance.

[0003] Polyurethane coatings have good flexibility, corrosion resistance, and good mechanical properties, and play an increasingly important role in fields such as ships, textiles, and buildings. Polyurethane anti-fouling coatings can be applied to fields such as the self-cleaning of windows, anti-graffiti of public facilities, and drag reduction of crude oil transportation pipelines. However, due to the inherent low surface energy characteristics of such coatings, it is difficult to balance the surface anti-fouling ability and the substrate bonding ability. In addition, during the use or transportation of the anti-fouling coating, it will inevitably face the harsh conditions of high temperature and high humidity. When serving in a humid environment for a long time, moisture gradually penetrates into the coating / substrate interface and the interior of the coating, which will cause coating plasticization and chemical degradation of the bonding interface, ultimately affecting the coating performance. In particular, under the coupled temperature-humidity conditions, moisture significantly accelerates the degradation of the coating bonding performance, triggering peeling or even falling off of the coating, thus losing the anti-fouling performance of the material surface. On the other hand, a high humidity environment will affect the elemental composition of the polymer surface, leading to surface chemical element reconstruction and destroying its surface anti-fouling performance. Therefore, how to simultaneously achieve high substrate bonding ability and long-term surface anti-fouling ability of polymer-based anti-fouling coatings in a high humidity environment is still an urgent problem to be solved.

[0004] Chinese Patent Publication No. CN115926604B discloses a polyurethane slow-release antifouling coating and its preparation method. Under anhydrous conditions, a highly absorbent silicone oil resin adsorbs a sufficient amount of silicone oil with an antifouling agent and then is mixed with a polyurethane resin. Subsequently, the modified polyurethane resin system is coated on a substrate and dried to obtain a polyurethane slow-release antifouling coating, which can extend the service life of the polyurethane slow-release antifouling coating. However, this method uses the silicone oil of the antifouling agent as the main antifouling component, and the antifouling agent is only attached to the surface and inside of the coating through physical action, which may lead to unstable waterproof, oil-proof, and antifouling effects under high-temperature and high-humidity conditions.

[0005] For the above reasons, it is urgent to study a polyurethane antifouling coating with long-term antifouling ability under high-temperature and high-humidity conditions. Summary of the Invention

[0006] Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide a high-temperature and high-humidity resistant antifouling coating and its manufacturing method. To solve the above technical problems, the present invention mainly utilizes the coordination addition reaction of silicon-hydrogen bonds and double bonds to graft ester compounds onto the side chain of hydrogen-containing silicone oil, synthesizes a crystalline polysiloxane-based polyol, and uses it in polyurethane synthesis to prepare a coating with excellent antifouling ability.

[0007] To achieve the above purpose, the present invention is realized through the following technical solutions:

[0008] A manufacturing method of a high-temperature and high-humidity resistant antifouling coating includes the following steps:

[0009] (1) Preparation of crystalline polysiloxane: Add a hydrogen-containing polysiloxane and an epoxy ester compound into a reaction kettle, control the molar ratio of -C=C / Si-H in the system at 0.3 - 0.6, heat up to 85°C, add a chloroplatinic acid catalyst under stirring, and react at 100 - 120°C for 1 - 2 h to obtain a crystalline polysiloxane containing both silicon-hydrogen bonds and epoxy side chains, and seal it for standby;

[0010] (2) Preparation of crystalline polysiloxane-based polyol: Subsequently, the crystalline polysiloxane prepared in step (1), methanol, and tetrabutylammonium bromide are refluxed at 75°C for 12 h, then methanol is removed by rotary evaporation, and the obtained crystalline polysiloxane-based polyol is obtained through centrifugal filtration and sealed for standby;

[0011] (3) Preparation of sewage-proof polyurethane emulsion: The crystalline polysiloxane obtained in step (2) is dehydrated, and the dehydrated crystalline polysiloxane-based polyol and polyester or polyether diol are added into a reaction flask. Then, diisocyanate and organotin catalyst are added in sequence. The temperature is raised to 65 - 95 °C, and after reacting for 2 h, a small molecule chain extender is added. After continuing to react at 50 - 80 °C for 1 - 2 h, a post-chain extender and a neutralizer are added. After reacting at 45 - 60 °C for 2 hours, deionized water is added under high-speed stirring for emulsification, and stirring is continued for 1 - 2 hours to obtain the sewage-proof polyurethane emulsion, which is sealed and reserved for use;

[0012] (4) Preparation of high-temperature and high-humidity resistant anti-fouling coating: The sewage-proof polyurethane emulsion, cross-linking agent, color powder, leveling agent and filler prepared in step (3) are mixed evenly at room temperature and reacted in an oven at 120 - 130 °C for 40 - 60 min to obtain the high-temperature and high-humidity resistant anti-fouling coating.

[0013] Preferably, in the preparation of the crystalline polysiloxane in step (1), the weight parts of the materials used are: 6 - 20 parts of the hydrogen-containing polysiloxane, 1 - 15 parts of the epoxy ester compound, and 1 - 2 parts of the chloroplatinic acid catalyst;

[0014] In the preparation of the crystalline polysiloxane in step (2), the weight parts of the materials used are: 8 - 30 parts of the crystalline polysiloxane, 16 - 60 parts of methanol, and 1 - 2 parts of tetrabutylammonium bromide.

[0015] Preferably, in the preparation of the sewage-proof polyurethane emulsion in step (3), the weight parts of the materials used are: 5 - 10 parts of the crystalline polysiloxane-based polyol, 10 - 20 parts of the polyester or polyether diol, 4 - 15 parts of the diisocyanate, 0.01 - 0.1 part of the organotin catalyst, 1 - 3 parts of the small molecule chain extender, 3 - 5 parts of the post-chain extender and neutralizer, and 90 - 120 parts of deionized water.

[0016] Preferably, in the preparation of the high-temperature and high-humidity resistant anti-fouling coating in step (4), the weight parts of the materials used are: 100 parts of the sewage-proof polyurethane emulsion, 8 - 15 parts of the cross-linking agent, 1 - 4 parts of the color powder, 0.3 - 1.0 part of the leveling agent, and 5 - 10 parts of the filler.

[0017] Preferably, in step (1), the hydrogen-containing polysiloxane is hydrogen-containing silicone oil with a hydrogen content of 0.8 - 1.6%, and its hydrogen atoms are located on the side chains of the polysiloxane;

[0018] Preferably, in step (1), the epoxy ester compound is one or a combination of more than one of 4-(oxiran-2-ylmethoxy)butyl acrylate, glycidyl methacrylate, 7-oxabicyclo[4.1.0]hept-3-yl methacrylate, 2-(oxiran-2-ylmethoxy)ethyl methacrylate, and 2-(2-(2-(acryloyloxy)ethoxy)ethoxy)ethyl 4-(oxiran-2-yl)butyrate.

[0019] Preferably, in step (3), the small molecule chain extender is one or a combination of more than one of N-(2-((4,6-diamino-1,3,5-triazin-2-yl)amino)ethyl)-3,4,5-trihydroxybenzamide, gallic acid, and m-phenylenediamine.

[0020] Preferably, in step (3), the diisocyanate is one or a combination of more than one of hexamethylene diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 2,4-toluene diisocyanate, and diphenylmethane diisocyanate MDI-50.

[0021] Preferably, in step (2), the crystalline polysiloxane polyol is one or a combination of more than one of polyethylene glycol with a number average molecular weight of 600 - 1000, polypropylene glycol with a number average molecular weight of 1000 - 4000, and poly(1,3-butylene adipate) diol with a number average molecular weight of 1000 - 2000.

[0022] A high-temperature and high-humidity resistant anti-fouling coating, a high-temperature and high-humidity resistant anti-fouling coating prepared by the preparation method according to any one of the above.

[0023] The high-temperature and high-humidity resistant anti-fouling coating of the present invention and its manufacturing method have the following beneficial effects:

[0024] 1. The high-temperature and high-humidity resistant anti-fouling coating of the present invention, by designing a polysiloxane with crystallization ability and introducing it into the polyurethane system, further controls the molecular movement ability of the polysiloxane chain segment (anti-fouling component), realizes the enhancement of the anti-surface reconstruction performance of the coating material under high-temperature and high-humidity conditions, and finally realizes the improvement of the long-term anti-fouling ability of the coating;

[0025] 2. The high-temperature and high-humidity resistant anti-fouling coating of the present invention, based on the bionic principle of mussels, introduces a small molecule chain extender with polyphenol structure into the polyurethane system, further enhances the interaction force between the coating and the substrate, enables the coating and the contact interface to maintain a strong adhesion force in a high-humidity environment, and thus improves the durability of the anti-fouling coating;

[0026] 3. The anti-fouling coating of the present invention with high temperature and high humidity resistance, during use, utilizes the surface energy balance to drive the selective orientation migration of the chain segments to the surface layer and the bottom layer. Not only a dense cross-linked network will be formed on the coating surface, but also crystallization will be formed based on the polyester chain segments. Its anti-fouling property and adhesion to the substrate are higher than those of general anti-fouling coatings, and its anti-fouling performance can be maintained persistently in high temperature and high humidity environments.

[0027] Explanation of the Drawings in the Specification

[0028] Figure 1 Schematic diagram of the change in the water contact angle of the anti-fouling coatings prepared in Examples 1-3 of the present invention;

[0029] Figure 2 Schematic diagram of the change in the diiodomethane contact angle of the anti-fouling coatings prepared in Examples 1-3 of the present invention;

[0030] Figure 3 Comparison diagram of the wiping results after marking with a marker pen between the anti-fouling coatings prepared in Examples 1-3 of the present invention and the blank sample;

[0031] Figure 4 Schematic diagram comparison under an atomic force microscope between the anti-fouling coatings prepared in Examples 1-3 of the invention and the blank sample. Detailed Embodiments

[0032] In order to enable those skilled in the art of the present technology to better understand the technical solution of the present invention, the products of the present invention will be further described in detail below in conjunction with the embodiments and the drawings.

[0033] It should be noted that all the technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0034] A manufacturing method of an anti-fouling coating with high temperature and high humidity resistance, comprising the following steps, and the parts of the materials used are all parts by weight:

[0035] (1) Preparation of crystalline polysiloxane: Add 6-20 parts of hydrogen-containing polysiloxane and 1-15 parts of epoxy ester compound into a reaction kettle, control the molar ratio of -C=C / Si-H in the system at 0.3-0.6, heat up to 85°C, add 1-2 parts of chloroplatinic acid catalyst under stirring, and react at 100-120°C for 1-2 h to obtain a crystalline polysiloxane containing both silicon-hydrogen bonds and epoxy side chains, and seal it for standby;

[0036] (2) Preparation of crystalline polysiloxane - based polyol: 8 - 30 parts of the crystalline polysiloxane prepared in step (1), 16 - 60 parts of methanol, and 1 - 2 parts of tetrabutylammonium bromide are refluxed at 75 °C for 12 h. Then, methanol is removed by rotary evaporation, and the obtained crystalline polysiloxane - based polyol is obtained by centrifugal filtration and stored in a sealed manner for later use;

[0037] (3) Preparation of sewage - resistant polyurethane emulsion: The crystalline polysiloxane - based polyol prepared in step (2) is dehydrated. Then, 5 - 10 parts of the dehydrated crystalline polysiloxane - based polyol and 10 - 20 parts of polyester or polyether diol are added into a reaction flask. Subsequently, 4 - 15 parts of diisocyanate and 0.01 - 0.1 part of organotin catalyst are added in sequence. The temperature is raised to 65 - 95 °C and reacted for 2 h. Then, 1 - 3 parts of small - molecule chain extender are added, and the reaction continues at 50 - 80 °C for 1 - 2 h. After that, 3 - 5 parts of post - chain extender and neutralizer are added, and the reaction is carried out at 45 - 60 °C for 2 h. Then, 90 - 120 parts of deionized water are added under high - speed stirring for emulsification, and continuous stirring is carried out for 1 - 2 h to obtain the sewage - resistant polyurethane emulsion, which is stored in a sealed manner for later use;

[0038] (4) Preparation of high - temperature and high - humidity resistant anti - fouling coating: 100 parts of the sewage - resistant polyurethane emulsion prepared in step (3), 8 - 15 parts of cross - linker, 1 - 4 parts of color powder, 0.3 - 1.0 part of leveling agent, and 5 - 10 parts of filler are mixed evenly at room temperature and reacted in an oven at 120 - 130 °C for 40 - 60 min to obtain the high - temperature and high - humidity resistant anti - fouling coating.

[0039] In step (1), the hydrogen - containing polysiloxane is hydrogen - containing silicone oil with a hydrogen content of 0.8 - 1.6%, and its hydrogen atoms are located on the side chains of the polysiloxane; the epoxy ester compound is one or a combination of 4 - (oxiran - 2 - ylmethoxy)butyl acrylate, glycidyl methacrylate, 7 - oxabicyclo[4.1.0]hept - 3 - ylmethyl methacrylate, 2 - (oxiran - 2 - ylmethoxy)ethyl methacrylate, 2 - (2 - (2 - (acryloyloxy)ethoxy)ethoxy)ethyl 4 - (oxiran - 2 - yl)butanoate.

[0040] In step (3), the small - molecule chain extender is one or a combination of N - (2 - ((4,6 - diamino - 1,3,5 - triazin - 2 - yl)amino)ethyl) - 3,4,5 - trihydroxybenzamide, gallic acid, and m - phenylenediamine.

[0041] In step (3), the diisocyanate is one or a combination of hexamethylene diisocyanate, isophorone diisocyanate, 4,4 - dicyclohexylmethane diisocyanate, 2,4 - toluene diisocyanate, and diphenylmethane diisocyanate MDI - 50.

[0042] In step (2), the crystalline polysiloxane-based polyol is one or a combination of more than one of polyethylene glycol with a number average molecular weight of 600 to 1000, polypropylene glycol with a number average molecular weight of 1000 to 4000, and poly(1,3-butylene adipate) glycol with a number average molecular weight of 1000 to 2000.

[0043] Example 1

[0044] A method for manufacturing a stain-resistant coating with high temperature and high humidity resistance, comprising the following steps, and the parts of the materials used are all parts by weight:

[0045] (1) Preparation of crystalline polysiloxane: Add 10 parts of hydrogen-containing polysiloxane with a hydrogen content of 0.18 and 1 part of glycidyl methacrylate to a reaction kettle, control the molar ratio of -C=C / Si-H in the system at 0.4, heat up to 85°C, add 1 part of chloroplatinic acid catalyst under stirring, and react at 100°C for 1 h to obtain a crystalline polysiloxane containing both silicon-hydrogen bonds and epoxy side chains, and seal it for standby;

[0046] (2) Preparation of crystalline polysiloxane-based polyol: Add 8 parts of the crystalline polysiloxane prepared in step (1), 30 parts of methanol, and 2 parts of tetrabutylammonium bromide, reflux and react at 75°C for 12 h, then rotary evaporate to remove methanol, and obtain the crystalline polysiloxane-based polyol through centrifugal filtration, and seal it for standby;

[0047] (3) Preparation of stain-resistant waterborne polyurethane emulsion: Dehydrate the crystalline polysiloxane-based polyol obtained in step (2), add 10 parts of the dehydrated crystalline polysiloxane-based polyol and 10 parts of polypropylene glycol with a number average molecular weight of 2000 to a reaction flask, then sequentially add 5 parts of 2,4-toluene diisocyanate and 0.05 part of organotin catalyst, heat up to 65 - 95°C, react for 2 h, then add 3 parts of m-phenylenediamine small molecule chain extender, continue to react at 50°C for 2 h, then add 3 parts of post-chain extender and neutralizer, react at 45°C for 2 h, add 120 parts of deionized water for emulsification under high-speed stirring, and continuously stir for 2 h to obtain a stain-resistant waterborne polyurethane emulsion, and seal it for standby;

[0048] (4) Preparation of stain-resistant coating with high temperature and high humidity resistance: Mix 100 parts of the stain-resistant waterborne polyurethane emulsion prepared in step (3), 8 parts of cross-linking agent, 2 parts of color powder, 0.5 part of leveling agent, and 10 parts of filler evenly at room temperature, and react in an oven at 130°C for 60 min to obtain a stain-resistant coating with high temperature and high humidity resistance.

[0049] As Figure 1 and Figure 2As shown in FIG. 1 , compared with the common waterborne polyurethane coating, the high temperature and high humidity resistant antifouling coating manufactured by the manufacturing method of Example 1 has excellent hydrophobicity and oleophobicity, the water contact angle is increased from 60° to 105°, the diiodomethane contact angle is increased from 39° to 80°, and the Figure 3 It can be seen that the coating obtained in Example 1 is compared with the ordinary water-based polyurethane coating (blank sample). The marker lines on the ordinary water-based polyurethane coating (blank sample) are also painted and then wiped off with a wet cotton cloth. The marker lines on the ordinary water-based polyurethane coating (blank sample) are still clearly visible, while the marker lines on the coating obtained in Example 1 can be wiped clean. It can be seen that the coating obtained in Example 1 also has good anti-graffiti performance. The handwriting written by the oil pen on the coating can be wiped off with a wet cotton cloth, and its performance can still be maintained after being placed at 40°C and 80% humidity for 12 hours; Figure 4 It can be seen from the data comparison chart of the atomic force microscope that when the coating obtained in Example 1 is compared with the ordinary water-based polyurethane coating (blank sample), the surface roughness of the ordinary water-based polyurethane coating (blank sample) is significantly greater than the surface roughness of the coating obtained in Example 1, that is, the surface flatness of the coating obtained in Example 1 is better, which is more conducive to obtaining better anti-fouling performance.

[0050] Example 2

[0051] A method for manufacturing a high temperature and high humidity resistant antifouling coating comprises the following steps, wherein the parts of the materials used are parts by weight:

[0052] (1) Preparation of crystalline polysiloxane: 15 parts of hydrogen-containing polysiloxane with a hydrogen content of 0.2 and 3 parts of 4-(oxirane-2-ylmethoxy)butyl acrylate are added to a reaction kettle, the molar ratio of the system -C=C / Si-H is controlled to be 0.5, the temperature is raised to 85° C., 1 part of chloroplatinic acid catalyst is added under stirring, and the reaction is carried out at 100° C. for 1 hour to obtain a crystalline polysiloxane containing both silicon-hydrogen bonds and epoxy side chains, which is then sealed for later use;

[0053] (2) Preparation of crystalline polysiloxane-based polyol: 10 parts of the crystalline polysiloxane prepared in step (1), 45 parts of methanol, and 2 parts of tetrabutylammonium bromide were refluxed at 75° C. for 12 h, and then the methanol was removed by rotary evaporation. The crystalline polysiloxane-based polyol obtained after centrifugal filtration was sealed and set aside;

[0054] (3) Preparation of anti-sewage polyurethane emulsion: The crystalline polysiloxane-based polyol obtained in step (2) was dehydrated, and 10 parts of the dehydrated crystalline polysiloxane-based polyol and 10 parts of poly(1,3-butylene adipate) diol with a number-average molecular weight of 2000 were added to a reaction flask. Then, 4 parts of isophorone diisocyanate and 0.05 part of organotin catalyst were added successively. The temperature was raised to 85 °C, and after reacting for 2 h, 3 parts of N-(2-((4,6-diamino-1,3,5-triazin-2-yl)amino)ethyl)-3,4,5-trihydroxybenzamide small molecule chain extender were added. After continuing to react at 50 °C for 2 h, 3 parts of post-chain extender and neutralizer were added. After reacting at 45 °C for 2 h, 120 parts of deionized water were added under high-speed stirring for emulsification, and stirring was continued for 2 h to obtain an anti-sewage polyurethane emulsion, which was sealed and reserved for use;

[0055] (4) Preparation of anti-fouling coating with high temperature and high humidity resistance: 100 parts of the anti-sewage polyurethane emulsion prepared in step (3), 10 parts of cross-linking agent, 2 parts of color powder, 0.5 part of leveling agent, and 8 parts of filler were mixed evenly at room temperature and reacted in an oven at 130 °C for 40 min to obtain an anti-fouling coating with high temperature and high humidity resistance.

[0056] As Figure 1 and Figure 2 shown, compared with the ordinary waterborne polyurethane coating, the anti-fouling coating with high temperature and high humidity resistance manufactured by the manufacturing method of Example 2 has excellent hydrophobic and oleophobic properties. The water contact angle is increased from 60° to 110°, and the diiodomethane contact angle is increased from 39° to 83°. It can be seen from Figure 3 that when comparing the coating obtained in Example 2 with the ordinary waterborne polyurethane coating (blank sample), the same marking pen was used to draw a line, and then wiped with a wet cotton cloth to remove. The marking pen line on the ordinary waterborne polyurethane coating (blank sample) was still clearly visible, while the marking pen line on the coating obtained in Example 2 could be wiped clean. Thus, it can be seen that the coating obtained in Example 2 has good anti-graffiti performance at the same time. The handwriting written with an oil-based pen on the coating can be scrubbed off with a wet cotton cloth. And, after being placed at 45 °C and 90% humidity for 12 h, its performance can still be maintained; It can be seen from Figure 4 the data comparison graph of the atomic force microscope that when comparing the coating obtained in Example 2 with the ordinary waterborne polyurethane coating (blank sample), the surface roughness of the ordinary waterborne polyurethane coating (blank sample) is significantly greater than that of the coating obtained in Example 2. That is to say, the surface flatness of the coating obtained in Example 2 is better, which is more conducive to obtaining better anti-fouling performance.

[0057] Example 3

[0058] A manufacturing method of an anti-fouling coating with high temperature and high humidity resistance, comprising the following steps, and the parts of the materials used are all parts by weight:

[0059] (1) Preparation of crystalline polysiloxane: 8 parts of hydrogen-containing polysiloxane with a hydrogen content of 1.6 and 7 parts of 7-oxabicyclo[4.1.0]hept-3-yl methacrylate were added to a reaction kettle. The molar ratio of -C=C / Si-H in the system was controlled at 0.3, and the temperature was raised to 85°C. 1 part of chloroplatinic acid catalyst was added under stirring, and the reaction was carried out at 100°C for 1 h to obtain a crystalline polysiloxane containing both silicon-hydrogen bonds and epoxy side chains, which was sealed for standby;

[0060] (2) Preparation of crystalline polysiloxane-based polyol: 15 parts of the crystalline polysiloxane prepared in step (1), 45 parts of methanol, and 2 parts of tetrabutylammonium bromide were refluxed at 75°C for 12 h, and then methanol was removed by rotary evaporation. The crystalline polysiloxane-based polyol obtained by centrifugal filtration was sealed for standby;

[0061] (3) Preparation of sewage-proof polyurethane emulsion: The crystalline polysiloxane-based polyol obtained in step (2) was dehydrated. 10 parts of the dehydrated crystalline polysiloxane-based polyol, 10 parts of poly(1,3-butylene adipate) diol with a number-average molecular weight of 2000, 10 parts of polyethylene glycol with a number-average molecular weight of 1000, and 5 parts of 4,4'-dicyclohexylmethane diisocyanate were added to a reaction flask. Then, 8 parts of isophorone diisocyanate and 0.05 part of organotin catalyst were added in sequence. The temperature was raised to 85°C, and after reacting for 2 h, 3 parts of m-phenylenediamine small molecule chain extender were added. After continuing to react at 50°C for 2 h, 3 parts of post-chain extender and neutralizer were added. After reacting at 45°C for 2 h, 120 parts of deionized water were added for emulsification under high-speed stirring, and stirring was continued for 2 h to obtain a sewage-proof polyurethane emulsion, which was sealed for standby;

[0062] (4) Preparation of anti-fouling coating with high temperature and high humidity resistance: 100 parts of the sewage-proof polyurethane emulsion prepared in step (3), 15 parts of cross-linking agent, 2 parts of color powder, 0.5 part of leveling agent, and 5 parts of filler were mixed evenly at room temperature and reacted in an oven at 120°C for 60 min to obtain an anti-fouling coating with high temperature and high humidity resistance.

[0063] As Figure 1 and Figure 2 shown, compared with ordinary waterborne polyurethane coatings, the anti-fouling coating with high temperature and high humidity resistance prepared by the manufacturing method of Example 3 has excellent hydrophobic and oleophobic properties. The water contact angle is increased from 60° to 120°, and the diiodomethane contact angle is increased from 39° to 81°; by Figure 3It can be seen that when compared with the ordinary waterborne polyurethane coating (blank sample), for the coatings obtained in Example 3, after scribing with a marker pen and then wiping with a water-dampened cotton cloth to remove, the marker pen scribing on the ordinary waterborne polyurethane coating (blank sample) is still clearly visible, while the marker pen scribing on the coatings obtained in Example 3 can be wiped clean. Thus, it can be seen that the coatings obtained in Example 3 have good anti-graffiti performance, and the handwriting written with an oil-based pen on the coatings can be scrubbed off with a water-dampened cotton cloth. Moreover, after being placed for 12 h under the conditions of 40 °C and 90% humidity, its performance can still be maintained. From Figure 4 From the data comparison diagram of the atomic force microscope, it can be seen that when compared with the ordinary waterborne polyurethane coating (blank sample), the surface roughness of the ordinary waterborne polyurethane coating (blank sample) is significantly greater than that of the coatings obtained in Example 3. That is to say, the surface flatness of the coatings obtained in Example 3 is better, which is more conducive to obtaining better anti-fouling performance.

[0064] The above is only a preferred embodiment of the present invention, and does not impose any form of limitation on the present invention. Any person skilled in the art can smoothly implement the present invention according to the description in the accompanying drawings and the above description. However, any minor changes, modifications, and equivalent variations made by those skilled in the art within the scope of the technical solution of the present invention by using the technical content disclosed above are equivalent embodiments of the present invention. At the same time, any equivalent changes, modifications, and variations made to the above embodiments based on the essence of the present invention still belong to the scope of the present invention.

Claims

1. A manufacturing method of a pollution-proof coating resistant to high temperature and high humidity, characterized in that, It includes the following steps: (1) Preparation of crystalline polysiloxane: Add hydrogen-containing polysiloxane and epoxy ester compound into a reaction kettle, control the molar ratio of -C=C / Si-H in the system to be 0.3 - 0.6, heat up to 85°C, add chloroplatinic acid catalyst under stirring, react at 100 - 120°C for 1 - 2 h to obtain a crystalline polysiloxane containing both silicon-hydrogen bond and epoxy side chain, and seal it for standby; (2) Preparation of crystalline polysiloxane-based polyol: Subsequently, add the crystalline polysiloxane prepared in step (1), methanol and tetrabutylammonium bromide, reflux and react at 75°C for 12 h, then rotary evaporate to remove methanol, and obtain a crystalline polysiloxane-based polyol through centrifugal filtration, and seal it for standby; (3) Preparation of sewage-proof polyurethane emulsion: Dehydrate the crystalline polysiloxane obtained in step (2), add the dehydrated crystalline polysiloxane-based polyol and polyester or polyether diol into a reaction flask, then successively add diisocyanate and organotin catalyst, heat up to 65 - 95°C, react for 2 h, add a small molecule chain extender, continue to react at 50 - 80°C for 1 - 2 h, then add a post-chain extender and a neutralizer, react at 45 - 60°C for 2 h, add deionized water for emulsification under high-speed stirring state, and continuously stir for 1 - 2 h to obtain a sewage-proof polyurethane emulsion, and seal it for standby; (4) Preparation of high-temperature and high-humidity resistant anti-fouling coating: Mix the sewage-proof polyurethane emulsion, crosslinking agent, color powder, leveling agent and filler prepared in step (3) evenly at room temperature, and react in an oven at 120 - 130°C for 40 - 60 min to obtain a high-temperature and high-humidity resistant anti-fouling coating.

2. The manufacturing method of the anti-fouling coating resistant to high temperature and high humidity according to claim 1, characterized in that, In the preparation of crystalline polysiloxane in step (1), the weight parts of the used materials are: 6 - 20 parts of the hydrogen-containing polysiloxane, 1 - 15 parts of the epoxy ester compound, and 1 - 2 parts of the chloroplatinic acid catalyst; In the preparation of crystalline polysiloxane in step (2), the weight parts of the used materials are: 8 - 30 parts of the crystalline polysiloxane, 16 - 60 parts of the methanol, and 1 - 2 parts of the tetrabutylammonium bromide.

3. The manufacturing method of the anti-fouling coating resistant to high temperature and high humidity according to claim 1, characterized in that, In the preparation of sewage-proof polyurethane emulsion in step (3), the weight parts of the used materials are: 5 - 10 parts of the crystalline polysiloxane-based polyol, 10 - 20 parts of the polyester or polyether diol, 4 - 15 parts of the diisocyanate, 0.01 - 0.1 part of the organotin catalyst, 1 - 3 parts of the small molecule chain extender, 3 - 5 parts of the post-chain extender and neutralizer, and 90 - 120 parts of the deionized water.

4. The manufacturing method of the anti-fouling coating resistant to high temperature and high humidity according to claim 1, characterized in that In the preparation of high-temperature and high-humidity resistant anti-fouling coating in step (4), the weight parts of the used materials are: 100 parts of the sewage-proof polyurethane emulsion, 8 - 15 parts of the crosslinking agent, 1 - 4 parts of the color powder, 0.3 - 1.0 part of the leveling agent, and 5 - 10 parts of the filler.

5. The manufacturing method of the anti-fouling coating resistant to high temperature and high humidity according to claim 1, characterized in that, In step (1), the hydrogen-containing polysiloxane is a hydrogen-containing silicone oil with a hydrogen content of 0.8 - 1.6%, and its hydrogen atoms are located on the side chain of the polysiloxane.

6. The manufacturing method of the anti-fouling coating resistant to high temperature and high humidity according to claim 1, characterized in that, In step (1), the epoxy ester compound is one or a combination of more than one of 4-(oxiran-2-ylmethoxy)butyl acrylate, glycidyl methacrylate, 7-oxabicyclo[4.1.0]hept-3-yl methacrylate, 2-(oxiran-2-ylmethoxy)ethyl methacrylate, and 2-(2-(2-(acryloyloxy)ethoxy)ethoxy)ethyl 4-(oxiran-2-yl)butyrate.

7. The manufacturing method of the anti-fouling coating resistant to high temperature and high humidity according to claim 1, characterized in that In step (3), the small molecule chain extender is one or a combination of more than one of N-(2-((4,6-diamino-1,3,5-triazin-2-yl)amino)ethyl)-3,4,5-trihydroxybenzamide, gallic acid, and m-phenylenediamine.

8. The manufacturing method of the anti-fouling coating resistant to high temperature and high humidity according to claim 1, characterized in that, In step (3), the diisocyanate is one or a combination of more than one of hexamethylene diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 2,4-toluene diisocyanate, and diphenylmethane diisocyanate MDI-50.

9. The manufacturing method of the anti-fouling coating resistant to high temperature and high humidity according to claim 1, characterized in that, In step (2), the crystalline polysiloxane polyol is one or a combination of more than one of polyethylene glycol with a number average molecular weight of 600 to 1000, polypropylene glycol with a number average molecular weight of 1000 to 4000, and poly(1,3-butylene adipate) diol with a number average molecular weight of 1000 to 2000.

10. An anti-fouling coating resistant to high temperature and high humidity, characterized in that, An anti-fouling coating resistant to high temperature and high humidity prepared by the preparation method according to any one of claims 1-9.

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