Silicon-modified polyurea resistance-reducing superhydrophobic coating material for water ice and shellfish adhesion and its preparation method

Abstract

This invention provides a silicon-modified polyurea superhydrophobic coating material for reducing water resistance and promoting adhesion to ice and shellfish, and its preparation method. The coating material comprises, by weight, 35-50 parts of a fully urea-bonded prepolymer, 30-45 parts of a PDMS-modified monofunctional urea-based polymer brush, 8-15 parts of a latent curing agent, 5-10 parts of a superhydrophobic nanofiller, 5-10 parts of a colorant, and 2-6 parts of a plasticizer; wherein the latent curing agent is a commercially available latent curing agent; and the superhydrophobic nanofiller is one or a mixture of two of fumed silica and nano-titanium dioxide. The coating material provided by this invention has the characteristics of a large contact angle, low roll-off angle, low surface energy, high strength, high elongation, low water absorption, and environmental friendliness.

Description

Technical Field

[0001] This invention belongs to the field of water conservancy and hydropower engineering, and relates to a silicon-modified polyurea impedance-reducing superhydrophobic coating material for water ice and shellfish adhesion, and its preparation method. Background Technology

[0002] Concrete, due to its excellent plasticity, economy, and strength properties, is widely used in infrastructure construction such as water conservancy projects. However, in practical applications, factors such as freezing, ice shearing, ultraviolet radiation, acid, alkali, and salt corrosion, alternating wet and dry conditions, erosion, and microbial adhesion significantly degrade the mechanical properties of concrete. This not only affects the healthy service performance of engineering structures but also increases the flow roughness, impacting the structural efficiency. The specific degradation mechanisms and conditions are briefly described below:

[0003] (1) Defects and deterioration factors in cold regions:

[0004] In cold regions, concrete structures are susceptible to damage during winter use due to sudden drops in temperature, ice pull, and seepage. On one hand, concrete dams, especially during the post-construction consolidation and hardening process, are prone to tensile stress internally or on the surface due to sudden drops in ambient temperature, which can lead to cracks in the concrete in severe cases. On the other hand, ice pull damage occurs when ice layers solidify on the water surface in areas of fluctuating water levels, causing upward or downward damage to the dam structure; the faster the water level changes, the more severe the ice pull damage. Furthermore, seepage damage occurs because concrete contains numerous micropores, allowing water to seep in. When the water freezes, its volume expands, and the expansion pressure acts on the pores, damaging the internal pores of the concrete and causing freeze-thaw damage.

[0005] (2) High-speed water flow erosion:

[0006] Scouring and cavitation are common engineering problems in the operation of hydraulic spillway structures. Over 70% of the spillway facilities in large-scale water conservancy projects in China suffer from scouring and cavitation damage. In recent years, with the continuous expansion of project scale, the flow velocity downstream of high dams has reached ultra-high velocities of 50 m / s, making the scouring and cavitation problems of spillway structures even more prominent. Under the action of high-speed water flow, the entire force of the flow acts on the concrete structure, causing severe erosion damage. Repairing this not only affects the normal operation of the water conservancy project but also incurs enormous costs.

[0007] (3) Microbial attachment:

[0008] Freshwater shellfish can grow in water conveyance structures with high flow rates and low dissolved oxygen levels, adapting to various environments. They are typical invasive benthic animals and easily cause biofouling. Similar in shape to seashells, they are triangular, with a yellow or dark outer wall and a purple inner wall. Their shell length ranges from 20 to 60 mm. They typically grow in clusters, reaching a thickness of 3 to 5 cm and a density of up to 87,000 per square meter. Freshwater shellfish feed on plankton and organic matter in the water and attach to channel walls using strong byssal threads. Their attachment to hydraulic concrete surfaces reduces the flow area and can block water conveyance channels, severely impacting the normal operation of water conveyance projects. The presence of freshwater shellfish in channels increases roughness and affects the channel's flow capacity. Furthermore, their growth corrodes the channel walls, damaging the engineering structure. Simultaneously, their respiration reduces dissolved oxygen in the channel water, and their excrement pollutes the water.

[0009] (4) Alternating between dry and wet conditions:

[0010] Hydraulic concrete structures undergo repeated cycles between dry and wet environments, causing expansion and contraction within the concrete, which leads to surface cracking and spalling. Furthermore, the alternation of dry and wet conditions accelerates the aging process of concrete, reducing its strength and toughness.

[0011] (5) Acid, alkali, and salt corrosion:

[0012] Hydraulic concrete structures deteriorate significantly in acidic and alkaline environments. Acids, alkalis, and salts corrode concrete structures, reducing their strength and durability. Salts also cause expansion and contraction within the concrete, leading to surface cracking and loosening. Salts and alkalis absorb moisture from the concrete, causing it to dry out too quickly and become brittle. Chlorides can penetrate the concrete and react with the reinforcing steel, causing corrosion and cracks. In acidic environments, acids corrode the cementitious materials in the concrete, leading to its destruction.

[0013] Applying a low surface energy hydrophobic coating to the concrete surface is a direct and effective way to comprehensively solve this problem. The hydrophobic properties can thicken the turbulent boundary layer on the coating surface, reducing fluid resistance. Combined with specially designed textured structures, it can produce coatings with important characteristics such as waterproofing, anti-fogging, snowproofing, anti-pollution, anti-adhesion, anti-oxidation, and anti-corrosion. Therefore, it has broad application prospects in the field of durability protection for hydraulic engineering structures. Low surface energy hydrophobic coatings are generally divided into two categories: one is a low surface energy coating with a smooth surface, where the static water contact angle is greater than 90°. Research on this coating technology started earlier and it has been widely used in the field of antifouling for exterior building walls. The other category is a hydrophobic coating material similar to the "lotus effect," such as organosilicon, which only has certain hydrophobic properties, and the contact angle is below 120°. Furthermore, if this type of product is directly used in hydraulic concrete structures, the alkaline nature of the concrete precipitates will affect the adhesion between the coating and the concrete. Under long-term immersion, its durability can only be maintained for 1-2 years. In addition, the addition of fluorine products further reduces its durability in aquatic environments.

[0014] Therefore, there is an urgent need for a coating material that can prevent algae growth, reduce roughness, and resist ice pull to solve the above problems. Summary of the Invention

[0015] To address the aforementioned problems, the present invention aims to provide a silicon-modified polyurea superhydrophobic coating material that reduces the resistance of water ice and promotes shellfish adhesion. This superhydrophobic coating material has the characteristics of reducing the resistance of water ice and promoting shellfish adhesion.

[0016] Another objective of this invention is to provide a method for preparing a silicon-modified polyurea resistive water ice and shellfish superhydrophobic coating material.

[0017] To achieve the above objectives, the present invention provides a silicon-modified polyurea resistance-reducing superhydrophobic coating material for water ice and shellfish adhesion, comprising, by weight, 35-50 parts of a fully urea-bonded prepolymer, 30-45 parts of a PDMS (polydimethylsiloxane) modified monofunctional urea-based polymer brush, 8-15 parts of a latent curing agent, 5-10 parts of a superhydrophobic nanofiller, 5-10 parts of a color paste, and 2-6 parts of a plasticizer;

[0018] The latent curing agent is an aldehyde-imide latent curing agent or an oxazolidine latent curing agent; the superhydrophobic nanofiller is one or a mixture of two of fumed silica and nano titanium dioxide.

[0019] As described above, the perureoyl prepolymer comprises, by weight, 7-15 parts of difunctional isocyanate, 5-10 parts of amino-terminated polybutadiene, and 20-30 parts of polyetheramine.

[0020] The NCO mass fraction of the perureoyl bond prepolymer is 6%–8%.

[0021] The difunctional isocyanate is one or a mixture of two of hexamethylene diisocyanate and isophorone diisocyanate.

[0022] The polyetheramine is one or a mixture of two of D2000 and T5000;

[0023] The plasticizer is coumarone resin.

[0024] As described above, the PDMS-modified monofunctional urea-based polymer brush comprises, by weight, 35-50 parts of CDI-modified urea-diamine, 20-25 parts of branched monoamino polysiloxane, and 20-25 parts of difunctional aliphatic isocyanate; the difunctional aliphatic isocyanate is one or a mixture of hexamethylene diisocyanate and isophorone diisocyanate; the NCO mass fraction of the PDMS-modified monofunctional urea-based polymer is 3%-6%.

[0025] The CDI-modified ureidodiamine is composed of 10-15 parts by weight of ureidopyrimidinone, 6-10 parts by weight of carbazide diimidazole, and 15-30 parts by weight of polyetheramine; the polyetheramine is one or a mixture of several of D230, D400, D600, and D2000.

[0026] The branched monoamino polysiloxane is composed of 2-5 parts silane coupling agent, 2-5 parts water, and 15-25 parts alcohol compound. The silane coupling agent is one or a mixture of two of KH550 and KH560; the alcohol compound is one of methanol and ethanol.

[0027] This invention also provides a method for preparing a silicon-modified polyurea resistive water ice and shellfish adhesion superhydrophobic coating material, comprising the following steps:

[0028] S1, Preparation of perurea bond prepolymer:

[0029] 1) Take the following ingredients by weight according to the specified proportions: difunctional isocyanate, amino-terminated polybutadiene, and polyetheramine;

[0030] 2) Place the isocyanate in the reaction vessel, turn on the stirring device, and rotate at 300-400 rpm;

[0031] 3) After mixing the amino-terminated polybutadiene and polyetheramine evenly, add them dropwise to the reaction vessel at a temperature of 15℃~40℃, and complete the addition within 1 hour;

[0032] 4) Maintain the temperature of the reactor between 15℃ and 40℃ and react for 4 to 6 hours to obtain the perurea bond prepolymer;

[0033] S2, Preparation of PDMS-modified monofunctional urea-based polymer brush:

[0034] (1) Raw material preparation:

[0035] 1) Preparation of CDI-modified ureadiamine:

[0036] a. Take ureidylpyrimidinone and carbazide according to the specified weight ratio;

[0037] b. Dissolve ureidylpyrimidinone and carbazide in dimethyl sulfoxide at 80°C and stir for at least 2 hours. After complete dissolution and homogeneity, cool to room temperature (25°C), filter, and wash with acetone at least 3 times to remove unreacted monomers to obtain amino-containing ureidylpyrimidinone;

[0038] c. Take ureidopyrimidinone and polyetheramine according to the specified weight ratio;

[0039] Urea-pyrimidinone and polyetheramine were placed in a reaction vessel and reacted for 12 to 18 hours under nitrogen protection, maintaining the temperature of the reaction vessel between 15°C and 40°C, to obtain CDI-modified urea-diamine.

[0040] 2) Preparation of branched monoamino polysiloxanes:

[0041] a. Take the silane coupling agent, water, and alcohol compound according to the specified weight ratio;

[0042] b. Place the silane coupling agent, water, and alcohol compound into a reaction vessel, and under nitrogen protection, maintain the temperature of the reaction vessel between 55℃ and 65℃ for 4 to 6 hours.

[0043] c. Distillation removes unreacted residual small molecules to obtain branched monoamino polysiloxane, which is a colorless and transparent liquid.

[0044] (2) Preparation of PDMS-modified monofunctional urea polymer brush:

[0045] a. Take CDI-modified urea-diamine, branched monoamino polysiloxane, and difunctional aliphatic isocyanate according to the specified weight ratio.

[0046] b. Bifunctional aliphatic isocyanates: Place the isocyanate in a reaction vessel, turn on the stirring device, and rotate at 300-400 rpm.

[0047] c. After mixing CDI-modified urea-diamine and branched monoamino polysiloxane evenly, add the mixture dropwise into the reaction vessel, ensuring that the addition is completed within 1 hour;

[0048] d. Maintain the temperature of the reactor between 15℃ and 40℃ and react for 4 to 6 hours to obtain PDMS-modified monofunctional urea polymer brush;

[0049] S3, Preparation of silicon-modified polyurea resistance-reducing superhydrophobic coating materials for water ice and shellfish adhesion:

[0050] a. According to the formula, take the total urea bond prepolymer, PDMS modified monofunctional urea polymer brush, latent curing agent, superhydrophobic nanofiller, color paste, and plasticizer;

[0051] b. Place the perurea prepolymer, PDMS-modified monofunctional urea polymer brush, latent curing agent, superhydrophobic nanofiller, pigments and fillers, and solvent into a high-speed stirrer;

[0052] c. Under the protection of nitrogen encapsulation, the rotation speed is maintained at 800 rpm, and the mixture is stirred evenly to obtain a silicon-modified polyurea impedance-reducing water ice and shellfish-attached superhydrophobic coating material.

[0053] The beneficial effects of this invention are as follows:

[0054] This invention provides a silicon-modified polyurea superhydrophobic coating material for reducing drag, preventing water ice and shellfish adhesion, and its preparation method. After application, this superhydrophobic coating material forms a green and environmentally friendly coating on the surface of hydraulic structures, exhibiting ultra-low surface energy (less than 40 mN / m), low water absorption (less than 1%), large contact angle (greater than 130°), low roll-off angle (less than 5°), and high mechanical properties (tensile strength greater than 3 MPa and elongation greater than 150%). This achieves drag reduction, roughness reduction, and resistance to shellfish (freshwater shellfish, barnacles, etc.) and water ice adhesion, increasing the flow rate of water conveyance structures, reducing water conveyance energy consumption and engineering operating costs, and ensuring the structural durability of hydraulic structures in cold regions against freeze-thaw cycles and ice pull. Detailed Implementation

[0055] The embodiments of the present invention will now be described in detail and comprehensively so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby providing a clearer and more explicit definition of the scope of protection of the present invention.

[0056] Based on research on the adhesion characteristics and ice pull mechanism of freshwater shellfish, this invention combines the hydrophobic properties of organosilicon materials with the high mechanical properties of polyurea to prevent the adhesion of freshwater shellfish, improve the flow capacity of concrete surfaces, reduce the roughness coefficient, meet the requirements for ice pull resistance in cold regions, and simultaneously provide seepage prevention and water-stopping functions under water pressure and deformation. First, polyetheramine, amino-terminated polybutadiene, and difunctional isocyanate are mixed to prepare a hydrophobic, fully urea-bonded prepolymer. Then, a branched monoamino polysiloxane is prepared by polymerizing a silane coupling agent with alcohol compounds and removing water. Finally, ureidopyrimidinone and carbon... Modified urea-based diamines were prepared by polymerizing amide-imidazolium. Then, branched monoamino polysiloxanes, branched monoamino polysiloxanes, and difunctional aliphatic isocyanates were mixed to prepare PDMS-modified monofunctional urea-based polymer brushes. Finally, a silicon-modified polyurea prepolymer, PDMS-modified monofunctional urea-based polymer brushes, latent curing agents, superhydrophobic nanofillers, color pastes, and plasticizers were mixed to prepare raw materials for silicon-modified polyurea resistance-reducing water ice and shellfish adhesion superhydrophobic coatings. After air curing, a silicon-modified polyurea resistance-reducing water ice and shellfish adhesion superhydrophobic coating with biomimetic lotus leaf surface characteristics was obtained. The PDMS-modified monofunctional urea-based polymer brushes possess a protruding spine-like structure reminiscent of a lotus leaf surface. This spine structure can form a larger contact angle and a lower roll-off angle, reducing surface energy and improving the hydrophobicity of the material.

[0057] Since urethane bonds are more easily hydrolyzed than urea bonds, the coating material provided by this invention has a structure that does not contain urethane bonds but has all-urea bonds, so as to improve the stability of the coating material.

[0058] The use of color paste is to ensure that the coating material is consistent with the application scenario. If the coating material is used in general engineering, gray color paste close to the color of concrete is often selected. When it is used around the bottom of a swimming pool, blue color paste is often selected. All color pastes are commercial products.

[0059] This invention provides a silicon-modified polyurea resistance-reducing superhydrophobic coating material for water ice and shellfish adhesion, comprising 35-50 parts by weight of a fully urea prepolymer, 30-45 parts by weight of a PDMS-modified monofunctional urea polymer brush, 8-15 parts by weight of a latent curing agent, 5-10 parts by weight of a superhydrophobic nanofiller, 5-10 parts by weight of a colorant, and 2-6 parts by weight of a plasticizer.

[0060] The latent curing agent is a commercially available latent curing agent; the superhydrophobic nanofiller is one or a mixture of two of fumed silica and nano titanium dioxide.

[0061] As described above, the perureoyl prepolymer comprises, by weight, 7-15 parts of difunctional isocyanate, 5-10 parts of amino-terminated polybutadiene, and 20-30 parts of polyetheramine.

[0062] The NCO mass fraction of the perureoyl bond prepolymer is 6%–8%.

[0063] The difunctional isocyanate is one or a mixture of two of hexamethylene diisocyanate and isophorone diisocyanate.

[0064] The polyetheramine is one or a mixture of two of D2000 and T5000;

[0065] The plasticizer is coumarone resin.

[0066] As described above, the PDMS-modified monofunctional urea-based polymer brush comprises, by weight, 35-50 parts of CDI-modified urea-diamine, 20-25 parts of branched monoamino polysiloxane, and 20-25 parts of difunctional aliphatic isocyanate; the difunctional aliphatic isocyanate is one or a mixture of hexamethylene diisocyanate and isophorone diisocyanate; the NCO mass fraction of the PDMS-modified monofunctional urea-based polymer is 3%-6%.

[0067] The CDI-modified ureidodiamine is composed of 10-15 parts by weight of ureidopyrimidinone, 6-10 parts by weight of carbazide diimidazole, and 15-30 parts by weight of polyetheramine; the polyetheramine is one or a mixture of several of D230, D400, D600, and D2000.

[0068] The branched monoamino polysiloxane is composed of 2-5 parts silane coupling agent, 2-5 parts water, and 15-25 parts alcohol compound. The silane coupling agent is one or more of KH550 and KH560; the alcohol compound is one of methanol and ethanol.

[0069] In this invention, all parts not specifically specified are parts by weight.

[0070] Unless otherwise specified, the raw material models used in the following embodiments are all conventional product models in the field, but this does not mean that only this model of product can be used. Products with the same effect can be substituted.

[0071] Example 1:

[0072] 1. The raw materials are synthesized according to the proportions shown in Table 1 below:

[0073] Table 1 Raw Material Ratio

[0074] raw materials Number of weights perurea bond prepolymer 44 PDMS modified monofunctional urea polymer brush 35 Superhydrophobic nanofillers 5 plasticizer 3 Pigment 5 Latent curing agent 8.62

[0075] The prepolymer of perurea bonds consists of 8 parts by weight of isophorone diisocyanate (IPDI), 5 parts by weight of amino-terminated polybutadiene, and 22 parts by weight of D2000. The NCO% of the prepolymer of perurea bonds prepared is 6.4%.

[0076] The PDMS-modified monofunctional urea-based polymer brush was prepared by using 50 parts by weight of CDI-modified urea-diamine, 20 parts by weight of branched monoamino polysiloxane, and 25 parts by weight of IPDI; the NCO% of the prepared PDMS-modified monofunctional urea-based polymer brush was 4.2%.

[0077] The CDI-modified ureidodiamine consists of 10 parts by weight of ureidopyrimidinone, 6.75 parts by weight of carbazide, and 16.64 parts by weight of D400.

[0078] The branched monoamino polysiloxane is composed of 2.21 parts by weight of KH550, 2.1 parts by weight of water, and 16 parts by weight of ethanol.

[0079] The latent curing agent is oxazolidine latent curing agent TP-830.

[0080] The superhydrophobic nanofiller is fumed silica.

[0081] The plasticizer is coumarone resin.

[0082] 2. The preparation steps are as follows:

[0083] S1, Preparation of perurea bond prepolymer:

[0084] 1) Take IPDI, amino-terminated polybutadiene, and polyetheramine D2000 according to the specified weight ratio;

[0085] 2) Place the difunctional isocyanate in the reactor, turn on the stirrer, and rotate at 300 rpm;

[0086] 3) After thoroughly mixing the amino-terminated polybutadiene and polyetheramine D2000, add them dropwise into the reaction vessel, ensuring the addition is completed within 1 hour;

[0087] Because the reaction between the amino-terminated material and isocyanate is fast and vigorous, it is necessary to control the reaction at low temperature and high speed throughout the process. At the same time, in order to prevent instantaneous agglomeration and thus prevent malignant cross-linking, the material needs to be added slowly dropwise to control the reaction.

[0088] 4) Maintain the temperature of the reactor at 30℃ and react for 4 hours to obtain the perurea bond prepolymer;

[0089] S2, Preparation of PDMS-modified monofunctional urea-based polymer brush:

[0090] (1) Raw material preparation:

[0091] 1) Preparation of CDI-modified ureadiamine:

[0092] a. Take ureidylpyrimidinone and carbazide according to the specified weight ratio;

[0093] b. Dissolve ureidylpyrimidinone and carbazide in dimethyl sulfoxide at 80°C and stir for more than 2 hours; after complete dissolution and uniform mixing, cool to room temperature (25°C), filter, and wash with acetone more than 3 times to remove unreacted monomers to obtain amino-containing ureidylpyrimidinone.

[0094] c. Take ureidopyrimidinone and polyetheramine according to the specified weight ratio;

[0095] Urea-pyrimidinone and polyetheramine were placed in a reaction vessel and reacted for 12 to 18 hours under nitrogen protection, maintaining the temperature of the reaction vessel between 15°C and 40°C, to obtain CDI-modified urea-diamine.

[0096] 2) Preparation of branched monoamino polysiloxanes:

[0097] a. Take the silane coupling agent KH550, water, and ethanol according to the specified weight ratio;

[0098] b. Place KH550, water, and ethanol into the reactor and react for 4 hours at 60°C under nitrogen protection.

[0099] c. Distillation removes unreacted residual small molecules to obtain branched monoamino polysiloxane, which is a colorless and transparent liquid.

[0100] (2) Preparation of PDMS-modified monofunctional urea polymer brush:

[0101] a. Take CDI-modified urea-diamine, branched monoamino polysiloxane, and IPDI according to the specified weight ratio.

[0102] b. Place the IPDI in the reactor and turn on the stirring device at a speed of 300-400 rpm.

[0103] c. After mixing CDI-modified urea-diamine and branched monoamino polysiloxane evenly, add the mixture dropwise into the reaction vessel, ensuring that the addition is completed within 1 hour;

[0104] d. Maintain the temperature of the reactor at 25℃ and react for 5 hours to obtain PDMS-modified monofunctional urea-based polymer brush;

[0105] S3, Preparation of silicon-modified polyurea resistance-reducing superhydrophobic coating materials for water ice and shellfish adhesion:

[0106] a. According to the formula, take the total urea bond prepolymer, PDMS modified monofunctional urea polymer brush, oxazolidine latent curing agent INCOZOL 4, superhydrophobic nanofiller, color paste, and coumarone resin.

[0107] b. Place the perurea prepolymer, PDMS-modified monofunctional urea polymer brush, latent curing agent, superhydrophobic nanofiller, color paste, and plasticizer into a high-speed mixer;

[0108] c. Under the protection of nitrogen encapsulation, the rotation speed is maintained at 800 rpm, and the mixture is stirred evenly to obtain a silicon-modified polyurea impedance-reducing water ice and shellfish-attached superhydrophobic coating material.

[0109] 3. Test the properties of the coating materials

[0110] After the coating material was applied and air-dried using conventional methods, the contact angle of the coating material was tested using the method provided in GB / T 30693-2014 "Measurement of Contact Angle between Plastic Film and Water"; the roll-off angle of the coating material was tested using the method provided in GB / T42694-2023 "Detection and Evaluation of Wetting Resistance of Textile Surfaces - Contact Angle and Roll-Off Angle Methods", and the surface energy of the coating material was tested using the contact angle method therein; the tensile strength and elongation at break of the coating material were tested using the method provided in GB / T 528-2009 "Determination of Tensile Stress-Strain Properties of Vulcanized Rubber or Thermoplastic Rubber"; the water absorption rate of the coating material was tested using the method provided in GB / T 23446-2009 "Sprayed Polyurea Waterproof Coating"; and the shear strength of the coating material against ice was tested using the method provided in GB / T 7124-2008 "Determination of Tensile Shear Strength of Adhesives (Rigid Material to Rigid Material)". The results are shown in Table 2.

[0111] Table 2 Performance of Synthetic Products:

[0112] project performance Contact angle 140° roll angle 4.8° Surface energy 35mN / m tensile strength 5MPa Elongation at break 180％ Water absorption rate 0.8％ Shear strength with ice 18 kPa

[0113] As shown in Table 2, the prepared coating material has a contact angle greater than 130°, a roll-off angle less than 5°, and a surface energy less than 40 mN / m. These low surface energy, large contact angle, and low roll-off angle indicate that the prepared coating material possesses excellent hydrophobic properties. Furthermore, the low surface energy prevents algae, freshwater shellfish, ice, and other organisms from adhering to hydraulic structures, reducing flow roughness, improving water conveyance efficiency, and achieving drag reduction and roughness reduction. Water absorption rate is an indicator of hydrophobicity; the prepared coating material's water absorption rate of less than 1% indicates good hydrophobic properties and also demonstrates good durability in aquatic environments. Existing materials with similar functions generally have a tensile strength of around 1 MPa and an elongation at break of only around 50%, which cannot meet application requirements. However, the tensile strength and elongation at break of the prepared coating material are significantly greater than those of existing materials with similar functions, indicating that the prepared coating material has excellent physical performance indicators. The shear strength between ice and ice represents the mechanical property of not being adhered to by ice. The lower the shear strength between ice and the anti-ice pull-out coating, the better the anti-ice pull-out effect. For example, 15 kPa can achieve the effect of ice being blown off a 10° slope by a force 4 wind. The shear strength between ice and coating materials in the prior art is generally over 100 kPa, while the shear strength between ice and coating materials in this embodiment is only 18 kPa, which is far lower than the shear strength between ice and coating materials in the prior art. This indicates that the coating material prepared in this embodiment has excellent anti-ice pull-out effect.

[0114] Example 2:

[0115] 1. The raw materials are synthesized according to the proportions shown in Table 3 below:

[0116] Table 3 Raw Material Ratio

[0117]

[0118]

[0119] The prepolymer of the perurea bond consists of 8 parts by weight of hexamethylene diisocyanate (HDI), 10 parts by weight of amino-terminated polybutadiene, and 20 parts by weight of T5000. The NCO% of the prepolymer of the perurea bond is 7.2%.

[0120] The PDMS-modified monofunctional urea-based polymer brush was prepared by using 40 parts by weight of CDI-modified urea-diamine, 22 parts by weight of branched monoamino polysiloxane, and 25 parts by weight of IPDI; the NCO% of the prepared PDMS-modified monofunctional urea-based polymer brush was 5.8%.

[0121] The CDI-modified ureidodiamine consists of 10 parts by weight of ureidopyrimidinone, 6.75 parts by weight of carbazide, and 16.64 parts by weight of D400.

[0122] The branched monoamino polysiloxane is composed of 2.21 parts by weight of KH550, 3 parts by weight of water, and 20 parts by weight of ethanol.

[0123] The latent curing agent is oxazolidine latent curing agent TP-830.

[0124] The superhydrophobic nanofiller is nano-titanium dioxide.

[0125] The plasticizer is coumarone resin.

[0126] 2. The preparation steps are as follows:

[0127] S1, Preparation of perurea bond prepolymer:

[0128] 1) Take HDI, amino-terminated polybutadiene, and polyetheramine D2000 according to the specified weight ratio;

[0129] 2) Place HDI in the reactor and turn on the stirring device at 350 rpm;

[0130] 3) After thoroughly mixing the amino-terminated polybutadiene and polyetheramine D2000, add them dropwise into the reaction vessel, ensuring the addition is completed within 1 hour;

[0131] 4) Maintain the temperature of the reactor at 30℃ and react for 4 hours to obtain the perurea bond prepolymer;

[0132] S2, Preparation of PDMS-modified monofunctional urea-based polymer brush:

[0133] (1) Raw material preparation:

[0134] 1) Preparation of CDI-modified ureadiamine:

[0135] a. Take ureidylpyrimidinone and carbazide according to the specified weight ratio;

[0136] b. Dissolve ureidylpyrimidinone and carbazide in dimethyl sulfoxide at 80°C and stir for more than 2 hours; after complete dissolution and uniform mixing, cool to room temperature (25°C), filter, and wash with acetone more than 3 times to remove unreacted monomers to obtain amino-containing ureidylpyrimidinone.

[0137] c. Take ureidopyrimidinone and polyetheramine according to the specified weight ratio;

[0138] Urea-pyrimidinone and polyetheramine were placed in a reaction vessel and reacted for 12 to 18 hours under nitrogen protection, maintaining the temperature of the reaction vessel between 15°C and 40°C, to obtain CDI-modified urea-diamine.

[0139] 2) Preparation of branched monoamino polysiloxanes:

[0140] a. Take the silane coupling agent KH550, water, and ethanol according to the specified weight ratio;

[0141] b. Place KH550, water, and ethanol into the reactor and react for 4 hours at 60°C under nitrogen protection.

[0142] c. Distillation removes unreacted residual small molecules to obtain branched monoamino polysiloxane, which is a colorless and transparent liquid.

[0143] (2) Preparation of PDMS-modified monofunctional urea polymer brush:

[0144] a. Take CDI-modified urea-diamine, branched monoamino polysiloxane, and IPDI according to the specified weight ratio.

[0145] b. Place the IPDI in the reactor and turn on the stirring device at a speed of 300-400 rpm.

[0146] c. After mixing CDI-modified urea-diamine and branched monoamino polysiloxane evenly, add the mixture dropwise into the reaction vessel, ensuring that the addition is completed within 1 hour;

[0147] d. Maintain the temperature of the reactor at 30°C and react for 5 hours to obtain PDMS-modified monofunctional urea-based polymer brush;

[0148] S3, Preparation of silicon-modified polyurea resistance-reducing superhydrophobic coating materials for water ice and shellfish adhesion:

[0149] a. According to the formula, take the total urea bond prepolymer, PDMS modified monofunctional urea polymer brush, latent curing agent TP-830, superhydrophobic nanofiller, color paste, and coumarone resin.

[0150] b. Place the perurea prepolymer, PDMS-modified monofunctional urea polymer brush, latent curing agent TP-830, superhydrophobic nanofiller, color paste, and coumarone resin into a high-speed mixer.

[0151] c. Under the protection of nitrogen encapsulation, the rotation speed is maintained at 800 rpm, and the mixture is stirred evenly to obtain a silicon-modified polyurea impedance-reducing water ice and shellfish-attached superhydrophobic coating material.

[0152] 3. Test the properties of the coating materials

[0153] After the coating material was applied and air-dried using conventional methods, the contact angle of the coating material was tested using the method provided in GB / T 30693-2014 "Measurement of Contact Angle between Plastic Film and Water"; the roll-off angle of the coating material was tested using the method provided in GB / T42694-2023 "Detection and Evaluation of Wetting Resistance of Textile Surfaces - Contact Angle and Roll-Off Angle Methods", and the surface energy of the coating material was tested using the contact angle method therein; the tensile strength and elongation at break of the coating material were tested using the method provided in GB / T 528-2009 "Determination of Tensile Stress-Strain Properties of Vulcanized Rubber or Thermoplastic Rubber"; the water absorption rate of the coating material was tested using the method provided in GB / T 23446-2009 "Sprayed Polyurea Waterproof Coating"; and the shear strength of the coating material against ice was tested using the method provided in GB / T 7124-2008 "Determination of Tensile Shear Strength of Adhesives (Rigid Material to Rigid Material)". The results are shown in Table 4.

[0154] Table 4 Performance of Synthetic Products:

[0155] project performance Contact angle 148° roll angle 4.1° Surface energy 30mN / m tensile strength 7MPa Elongation at break 151％ Water absorption rate 0.5％ Shear strength with ice 15 kPa

[0156] As shown in Table 4, the prepared coating material has a contact angle greater than 130°, a roll-off angle less than 5°, and a surface energy less than 40 mN / m. These low surface energy, large contact angle, and low roll-off angle indicate that the prepared coating material possesses excellent hydrophobic properties. Simultaneously, the low surface energy prevents algae, freshwater shellfish, ice, and other organisms from adhering to hydraulic structures, reducing flow roughness, improving water conveyance efficiency, and achieving drag reduction and roughness reduction effects. Water absorption rate is an indicator of hydrophobicity; the prepared coating material's water absorption rate of less than 1% indicates good hydrophobic properties and also demonstrates good durability in aquatic environments. Existing materials with similar functions generally have a tensile strength of around 1 MPa and an elongation at break of only around 50%, which cannot meet application requirements. However, the tensile strength and elongation at break of the prepared coating material are significantly higher than those of existing materials with similar functions, indicating that the prepared coating material has excellent physical performance indicators. In this embodiment, the shear strength of the coating material against ice is only 15 kPa, far lower than the shear strength of coating materials against ice in existing technologies, indicating that the coating material prepared in this embodiment has excellent ice pull-out resistance.

[0157] Example 3:

[0158] 1. The raw materials are synthesized according to the proportions shown in Table 5 below:

[0159] Table 5 Raw Material Ratio

[0160] raw materials Number of weights perurea bond prepolymer 42 PDMS modified monofunctional urea polymer brush 35 Superhydrophobic nanofillers 5 plasticizer 3 Pigment 5 Latent curing agent 9.40

[0161] The prepolymer of the perurea bond consists of 10 parts by weight of IPDI, 8 parts by weight of amino-terminated polybutadiene, 10 parts by weight of D2000, and 20 parts by weight of T5000. The NCO% of the prepolymer of the perurea bond is 6.5%.

[0162] The PDMS-modified monofunctional urea-based polymer brush was prepared by using 38 parts by weight of CDI-modified urea-diamine, 20 parts by weight of branched monoamino polysiloxane, and 25 parts by weight of HDI. The NCO% of the prepared PDMS-modified monofunctional urea-based polymer brush was 5.6%.

[0163] The CDI-modified ureidodiamine consists of 10 parts by weight of ureidopyrimidinone, 6.75 parts by weight of carbazide, and 30 parts by weight of D600.

[0164] The branched monoamino polysiloxane is composed of 3 parts by weight of KH550, 5 parts by weight of water, and 23 parts by weight of ethanol.

[0165] The latent curing agent is oxazolidine latent curing agent TP-830.

[0166] The superhydrophobic nanofiller is fumed silica.

[0167] The plasticizer is coumarone resin.

[0168] 2. The preparation steps are as follows:

[0169] S1, Preparation of perurea bond prepolymer:

[0170] 1) Take IPDI, amino-terminated polybutadiene, and polyetheramine D2000 according to the specified weight ratio;

[0171] 2) Place the IPDI in the reactor, turn on the stirrer, and set the speed to no less than 300-400 rpm;

[0172] 3) After thoroughly mixing the amino-terminated polybutadiene and polyetheramine D2000, add them dropwise into the reaction vessel, ensuring the addition is completed within 1 hour;

[0173] 4) Maintain the temperature of the reactor at 25°C and react for 5 hours to obtain the perurea bond prepolymer;

[0174] S2, Preparation of PDMS-modified monofunctional urea-based polymer brush:

[0175] (1) Raw material preparation:

[0176] 1) Preparation of CDI-modified ureadiamine:

[0177] a. Take ureidylpyrimidinone and carbazide according to the specified weight ratio;

[0178] b. Dissolve ureidylpyrimidinone and carbazide in dimethyl sulfoxide at 80°C and stir for more than 2 hours; after complete dissolution and uniform mixing, cool to room temperature (25°C), filter, and wash with acetone more than 3 times to remove unreacted monomers to obtain amino-containing ureidylpyrimidinone.

[0179] c. Take ureidopyrimidinone and polyetheramine according to the specified weight ratio;

[0180] Urea-pyrimidinone and polyetheramine were placed in a reaction vessel and reacted for 12 to 18 hours under nitrogen protection, maintaining the temperature of the reaction vessel between 15°C and 40°C, to obtain CDI-modified urea-diamine.

[0181] 2) Preparation of branched monoamino polysiloxanes:

[0182] a. Take the silane coupling agent KH550, water, and ethanol according to the specified weight ratio;

[0183] b. Place KH550, water, and ethanol into a reaction vessel, and under nitrogen protection, maintain the temperature of the reaction vessel at 60°C for 5 hours.

[0184] c. Distillation removes unreacted residual small molecules to obtain branched monoamino polysiloxane, which is a colorless and transparent liquid.

[0185] (2) Preparation of PDMS-modified monofunctional urea polymer brush:

[0186] a. Take CDI-modified urea-diamine, branched monoamino polysiloxane, and HDI according to the specified weight ratio;

[0187] b. Place HDI in the reactor, turn on the stirring device, and set the speed to no less than 300 rpm;

[0188] c. After mixing CDI-modified urea-diamine and branched monoamino polysiloxane evenly, add the mixture dropwise into the reaction vessel, ensuring that the addition is completed within 1 hour;

[0189] d. Maintain the temperature of the reactor at 30°C and react for 4 hours to obtain PDMS-modified monofunctional urea polymer brush;

[0190] S3, Preparation of silicon-modified polyurea resistance-reducing superhydrophobic coating materials for water ice and shellfish adhesion:

[0191] a. According to the formula, take the total urea bond prepolymer, PDMS modified monofunctional urea polymer brush, latent curing agent, superhydrophobic nanofiller, color paste, plasticizer coumarone resin;

[0192] b. Place the perurea prepolymer, PDMS-modified monofunctional urea polymer brush, latent curing agent, superhydrophobic nanofiller, color paste, and coumarone resin into a high-speed mixer;

[0193] c. Under the protection of nitrogen encapsulation, the rotation speed is maintained at 800 rpm, and the mixture is stirred evenly to obtain a silicon-modified polyurea impedance-reducing water ice and shellfish-attached superhydrophobic coating material.

[0194] 3. Test the properties of the coating materials

[0195] After the coating material was applied and air-dried using conventional methods, the contact angle of the coating material was tested using the method provided in GB / T 30693-2014 "Measurement of Contact Angle between Plastic Film and Water"; the roll-off angle of the coating material was tested using the method provided in GB / T42694-2023 "Detection and Evaluation of Wetting Resistance of Textile Surfaces - Contact Angle and Roll-Off Angle Methods", and the surface energy of the coating material was tested using the contact angle method therein; the tensile strength and elongation at break of the coating material were tested using the method provided in GB / T 528-2009 "Determination of Tensile Stress-Strain Properties of Vulcanized Rubber or Thermoplastic Rubber"; the water absorption rate of the coating material was tested using the method provided in GB / T 23446-2009 "Sprayed Polyurea Waterproof Coating"; and the shear strength of the coating material against ice was tested using the method provided in GB / T 7124-2008 "Determination of Tensile Shear Strength of Adhesives (Rigid Material to Rigid Material)". The results are shown in Table 6.

[0196] Table 6. Performance of Synthetic Products:

[0197]

[0198]

[0199] As shown in Table 6, the prepared coating material has a contact angle greater than 130°, a roll-off angle less than 5°, and a surface energy less than 40 mN / m. These low surface energy, large contact angle, and low roll-off angle indicate that the prepared coating material possesses excellent hydrophobic properties. Simultaneously, the low surface energy prevents algae, freshwater shellfish, ice, and other organisms from adhering to hydraulic structures, reducing flow roughness, improving water conveyance efficiency, and achieving drag reduction and roughness reduction effects. Water absorption rate is an indicator of hydrophobicity; the prepared coating material's water absorption rate of less than 1% indicates good hydrophobic properties and also demonstrates good durability in aquatic environments. Existing materials with similar functions generally have a tensile strength of around 1 MPa and an elongation at break of only around 50%, which cannot meet application requirements. However, the tensile strength and elongation at break of the prepared coating material are significantly higher than those of existing materials with similar functions, indicating that the prepared coating material has excellent physical performance indicators. In this embodiment, the shear strength of the coating material against ice is only 20 kPa, far lower than the shear strength of coating materials against ice in existing technologies, indicating that the coating material prepared in this embodiment has excellent anti-ice pull-out effect.

[0200] As can be seen from the above embodiments, the superhydrophobic coating material prepared by the present invention has the characteristics of large contact angle (contact angle greater than 130°), low roll-off angle (roll-off angle less than 5°), low surface energy (surface energy less than 40mN / m), high strength (tensile strength greater than 3MPa), high elongation (elongation greater than 150%), low water absorption (water absorption less than 1%), and green environmental protection.

[0201] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A silicon-modified polyurea drag-reducing anti-icing and marine biofouling superhydrophobic coating material, characterized in that, The full urea bond prepolymer 35-50 parts by weight, PDMS modified monofunctional urea-based polymer brush 30-45 parts, latent curing agent 8-15 parts, super-hydrophobic nano filler 5-10 parts, color paste 5-10 parts, plasticizer 2-6 parts; Wherein, the latent curing agent is aldehyde imine latent curing agent or oxazolidine latent curing agent; the super-hydrophobic nano filler is one or a mixture of both of gas phase silicon dioxide and nano titanium dioxide; The full urea bond prepolymer includes 7-15 parts by weight of difunctional isocyanate, 5-10 parts of terminal amino polybutadiene, and 20-30 parts of polyether amine; Wherein, the NCO mass fraction of the full urea bond prepolymer is 6%-8%; The difunctional isocyanate is one or a mixture of both of hexamethylene diisocyanate and isophorone diisocyanate; The polyether amine is one or a mixture of both of D2000 and T5000; The plasticizer is coumarone resin; The PDMS modified monofunctional urea-based polymer brush includes 35-50 parts by weight of CDI modified urea-based diamine, 20-25 parts of branched monoamino polysiloxane, and 20-25 parts of difunctional aliphatic isocyanate; the difunctional aliphatic isocyanate is one or a mixture of more than one of hexamethylene diisocyanate and isophorone diisocyanate; the NCO mass fraction of the PDMS modified monofunctional urea-based polymer is 3%-6%; Wherein, the CDI modified urea-based diamine is composed of 10-15 parts of urea-based pyrimidinone, 6-10 parts of carbonyl diimidazole, and 15-30 parts of polyether amine by weight; The branched monoamino polysiloxane is composed of 2-5 parts of silane coupling agent, 2-5 parts of water, and 15-25 parts of alcohol compound; wherein, the silane coupling agent is KH550; the alcohol compound is methanol or ethanol.

2. The method for preparing the silicon-modified polyurea drag-reducing water- resistant ice and shellfish-attachment-resistant super-hydrophobic coating material according to claim 1, characterized in that, The method comprises the following steps: S1, preparing a full urea bond prepolymer: 1) According to the weight ratio, take difunctional isocyanate, terminal amino polybutadiene, and polyether amine; 2) Put the difunctional isocyanate into the reaction kettle, start the stirring device, and rotate at a speed of 300-400 revolutions per minute; 3) Mix the terminal amino polybutadiene and polyether amine uniformly, then drop them into the reaction kettle at a temperature of 15-40℃, and require that the dropping be completed within 1 hour; 4) Keep the temperature of the reaction kettle between 15-40℃, and react for 4-6 hours to obtain the full urea bond prepolymer; S2, preparing PDMS-modified monofunctional urea-based polymer brushes ： (1) Raw material preparation: 1) Preparing CDI modified urea-based diamine: a. According to the weight ratio, take urea-based pyrimidinone and carbonyl diimidazole; b. Dissolve the urea-based pyrimidinone and carbonyl diimidazole in dimethyl sulfoxide solvent at 80℃ and stir for more than 2 hours; after complete dissolution and uniform mixing, cool to room temperature, filter, and wash with acetone for more than 3 times to remove unreacted monomers to obtain urea-based pyrimidinone containing amino groups; c. According to the weight ratio, take urea-based pyrimidinone containing amino groups and polyether amine; The amino-containing urea-based pyrimidone and polyether amine are placed in a reaction kettle, and the temperature of the reaction kettle is kept between 15℃ and 40℃ under nitrogen protection for 12-18 hours to obtain CDI modified urea-based diamine; 2) Preparation of branched monoamino polysiloxane: a. According to the proportioning weight, take the silane coupling agent, water, and alcohol compound; b. The silane coupling agent, water, and alcohol compound are placed in a reaction kettle, and the temperature of the reaction kettle is kept between 55℃ and 65℃ under nitrogen protection for 4-6 hours; c. Distill the unreacted residual small molecules to obtain branched monoamino polysiloxane in the form of colorless transparent liquid; (2) Preparation of PDMS modified mono-functionality urea-based polymer brush: a. According to the proportioning weight, take the CDI modified urea-based diamine, branched monoamino polysiloxane, and bifunctional aliphatic isocyanate; b. The bifunctional aliphatic isocyanate is placed in a reaction kettle, and the stirring device is turned on at a speed of 300-400 revolutions per minute; c. The CDI modified urea-based diamine and branched monoamino polysiloxane are mixed uniformly and then added dropwise into the reaction kettle, which requires 1 hour for complete addition; d. The temperature of the reaction kettle is kept between 15℃ and 40℃, and the reaction is carried out for 4-6 hours to obtain PDMS modified mono-functionality urea-based polymer brush; S3, preparation of silicon modified polyurea drag reduction and ice-resistant and shellfish attachment super-hydrophobic coating material: a. According to the proportioning, take the full urea bond prepolymer, PDMS modified mono-functionality urea-based polymer brush, latent curing agent, super-hydrophobic nano filler, color paste, and plasticizer; b. The full urea bond prepolymer, PDMS modified mono-functionality urea-based polymer brush, latent curing agent, super-hydrophobic nano filler, color paste, and plasticizer are placed in a high-speed stirrer; c. Under the action of nitrogen sealing protection, the stirring speed is kept at 800 revolutions per minute to obtain silicon modified polyurea drag reduction and ice-resistant and shellfish attachment super-hydrophobic coating material.

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