Phenylsilane modified amino siloxane oligomer, hydrophobic anticorrosive polyurea coating and preparation methods of phenylsilane modified amino siloxane oligomer and hydrophobic anticorrosive polyurea coating

Abstract

The invention relates to the field of polyurea materials, and provides a phenylsilane modified amino siloxane oligomer, a hydrophobic anti-corrosion polyurea coating and a preparation method of the phenylsilane modified amino siloxane oligomer and the hydrophobic anti-corrosion polyurea coating in order to solve the problem that an existing polyurea material is poor in water resistance and corrosion resistance. The preparation method comprises the following steps: adding 1, 3-bis (3-aminopropyl) tetramethyldisiloxane into a reaction kettle, carrying out an end-capping reaction, and carrying out a vacuum removal process to prepare the oligomer; the structural general formula of the component A is as shown in formula (1): in the formula (1), R1-R8 are selected from phenyl or alkyl, and at least one of R1-R8 is phenyl; the component A comprises one or more compounds conforming to the structure of a formula (1). The modified siloxane oligomer provided by the invention has an amino-terminated group and a phenyl side chain, and can generate a prepolymer with isocyanate, and further generate polyurea with a polyurea component B. Due to hydrophobicity and stability of a phenyl side chain and a siloxane chain segment, water resistance and corrosion resistance of polyurea are greatly improved.

Description

Technical Field

[0001] This invention relates to the field of polyurea materials, and more specifically, to a phenylsilane-modified aminosiloxane oligomer, a hydrophobic and anti-corrosion polyurea coating, and methods for preparing the two. Background Technology

[0002] Polyurea is a polymer material formed by a stepwise addition reaction of isocyanate and amino compound components. Due to its excellent physical properties, chemical resistance, and abrasion resistance, this material has wide applications in various fields. However, while traditional polyurea possesses advantages such as high mechanical strength and rapid curing, the polar urea bonds (-NH-CO-NH-) in the molecular chain easily form hydrogen bonds with water molecules, leading to increased water absorption, decreased corrosion resistance, and performance degradation under long-term exposure to humid environments.

[0003] Currently, common modification methods to improve the water resistance and corrosion resistance of polyurea materials include:

[0004] Adding small molecule silicone oil to polyurea materials can improve their water resistance and corrosion resistance, as silicone oil has advantages such as low surface energy and good hydrophobicity. However, small molecule silicone oil is prone to migration and precipitation.

[0005] Polyurea materials are physically blended with hydrophobic fillers to enhance their water resistance and corrosion resistance. However, during physical blending, the compatibility between materials can severely affect their performance, especially after long-term exposure to the external environment. As the materials age, their compatibility further deteriorates, leading to a significant reduction in performance. Summary of the Invention

[0006] The purpose of this invention is to provide a phenylsilane-modified aminosiloxane oligomer, a hydrophobic and anti-corrosion polyurea coating, and a method for preparing both, thereby solving the problems of poor water resistance and corrosion resistance of existing polyurea materials.

[0007] The embodiments of the present invention are achieved through the following technical solutions:

[0008] A method for preparing a phenylsilane-modified aminosiloxane oligomer includes: adding tetramethylammonium hydroxide to component A, performing a ring-opening reaction, adding 1,3-bis(3-aminopropyl)tetramethyldisiloxane, performing an end-capping reaction, and then obtaining the phenylsilane-modified aminosiloxane oligomer through a vacuum removal process.

[0009] The general structural formula of component A is as shown in formula ( As shown in the image:

[0010]

[0011] Mode( )

[0012] Wherein, R1~R8 are selected from phenyl or alkyl, and at least one is phenyl. Component A includes: conforming to formula ( One or more compounds with the structure )

[0013] The mass ratio of component A to tetramethylammonium hydroxide is 1:(0.01~0.03).

[0014] The ring-opening reaction is carried out at a temperature of 60-85°C for 1-3 hours.

[0015] The solvent for the system can be dimethyl sulfoxide, DMF or toluene.

[0016] Preferably, component A comprises one or more of tetramethyltetraphenylcyclotetrasiloxane and octaphenylcyclotetrasiloxane.

[0017] Preferably, the mass ratio of component A to 1,3-bis(3-aminopropyl)tetramethyldisiloxane is 1:(0.2~0.5).

[0018] Preferably, the end-capping reaction is carried out at 60-85°C for 1-3 hours, and then cooled to 40-50°C for another 1-3 hours.

[0019] Preferably, the temperature of the vacuum removal process is 100~120℃ and the pressure is -0.09~-0.1 MPa.

[0020] A phenylsilane-modified aminosiloxane oligomer prepared by the aforementioned method.

[0021] A method for preparing a hydrophobic and anti-corrosion polyurea coating, comprising:

[0022] After the polyether reacts with the diisocyanate, the phenylsilane-modified aminosiloxane oligomer of claim 8 is added dropwise. After the reaction is complete, an active diluent is added to obtain the sprayable polyurea component A.

[0023] After mixing and dehydrating polyetheramine, polyether, chain extender, color paste, filler, additives and catalyst, the sprayable polyurea component B is obtained;

[0024] The hydrophobic and anti-corrosion polyurea coating comprises: sprayed polyurea component A and sprayed polyurea component B.

[0025] The polyether can be polytetrahydrofuran ether diol, hydroxyl-terminated polybutadiene, or polyoxypropylene ether polyol.

[0026] The diisocyanate may be selected from diphenylmethane-4,4-diisocyanate, diphenylmethane-2,4-diisocyanate, cyclohexanedimethylene diisocyanate, hexamethylene diisocyanate, or isophorone diisocyanate or mixtures thereof.

[0027] The reactive diluent can be propylene carbonate or ethylene carbonate.

[0028] Liquid chain extenders such as UNILINK4200, E100, and E300 can be selected.

[0029] The catalyst can be an organobismuth or organotin compound, with organobismuth being preferred.

[0030] Preferably, the polyether is vacuum dehydrated at -0.09 to -0.1 MPa and 100 to 120°C for 1 to 3 hours. After cooling to below 40°C, diisocyanate is added, the temperature is raised to 75 to 85°C, and the reaction is carried out for 2 to 4 hours. Then the temperature is lowered to 40 to 50°C, and phenylsilane-modified aminosiloxane oligomer is added dropwise over 2 to 4 hours. The reaction is then carried out for another 0.5 to 1 hour, and then an active diluent is added to obtain the sprayable polyurea component A.

[0031] For temperatures below 45℃, 35℃ is preferred.

[0032] Preferably, after mixing polyetheramine, polyether, chain extender, color paste, filler, additives and catalyst, the system is heated to 100~120℃, and moisture is removed at -0.09~-0.1 MPa. After 1~3 hours, the system is cooled to obtain the sprayable polyurea B component.

[0033] A hydrophobic and anti-corrosion polyurea coating prepared by the aforementioned method.

[0034] The present invention has at least the following beneficial effects:

[0035] The phenylsilane-modified aminosiloxane oligomer provided by this invention is a chemically synthesized siloxane oligomer with terminal amino groups and phenyl side chains, and an average molecular weight of 800-2000. After reacting with isocyanate to form a prepolymer, and further reacting with the B component of a sprayed polyurea to form a polyurea, the hydrophobic effect of the phenyl side chains and siloxane segments, low surface energy, and the rigid structure of the benzene ring improve the coating's density, water resistance, and corrosion resistance. The polyurea material has a water contact angle >115°, a 24-hour water absorption rate <1%, and retains >85% of its mechanical properties after 1000 hours of UV aging. In a 2000-hour salt spray test, it does not rust, bubble, or peel off. The polyurea material provided by this invention is suitable for waterproofing and corrosion protection projects in harsh environments, possessing superior physical properties, water resistance, corrosion resistance, and aging resistance. Detailed Implementation

[0036] To make the objectives, methods, and advantages of the embodiments of the present invention clearer, the methods in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments.

[0037] Example 1: A method for preparing a phenylsilane-modified aminosiloxane oligomer, comprising: mixing component A with dimethyl sulfoxide at a mass ratio of 1:1, dissolving the mixture at 60°C and 200 r / min under stirring, uniformly mixing, adding tetramethylammonium hydroxide to carry out a ring-opening reaction, adding 1,3-bis(3-aminopropyl)tetramethyldisiloxane to carry out an end-capping reaction, and then removing solvent, water and small molecule organic matter by a vacuum removal process, and obtaining the phenylsilane-modified aminosiloxane oligomer after 1 hour;

[0038] Component A includes: tetramethyltetraphenylcyclotetrasiloxane;

[0039] The mass ratio of component A to tetramethylammonium hydroxide is 1:0.01;

[0040] The mass ratio of component A to 1,3-bis(3-aminopropyl)tetramethyldisiloxane is 1:0.2;

[0041] Conditions for the end-capping reaction: react at 60°C for 1 hour, then cool to 40°C and continue the reaction for 1 hour;

[0042] The vacuum removal process is carried out at a temperature of 100℃ and a pressure of -0.09MPa.

[0043] Example 2: A method for preparing a phenylsilane-modified aminosiloxane oligomer, comprising: mixing component A with dimethyl sulfoxide at a mass ratio of 1:1, dissolving the mixture at 85°C and 600 r / min under stirring, uniformly mixing, adding tetramethylammonium hydroxide for ring-opening reaction, adding 1,3-bis(3-aminopropyl)tetramethyldisiloxane for end-capping reaction, and then removing solvent, water and small molecule organic matter by vacuum removal process, obtaining the phenylsilane-modified aminosiloxane oligomer after 3 hours;

[0044] Component A includes: octaphenylcyclotetrasiloxane;

[0045] The mass ratio of component A to tetramethylammonium hydroxide is 1:0.03;

[0046] The mass ratio of component A to 1,3-bis(3-aminopropyl)tetramethyldisiloxane is 1:0.5;

[0047] Conditions for the end-capping reaction: react at 85℃ for 3 hours, then cool to 50℃ and continue the reaction for 3 hours;

[0048] The vacuum removal process is carried out at a temperature of 120℃ and a pressure of -0.1 MPa.

[0049] Example 3: A method for preparing a phenylsilane-modified aminosiloxane oligomer, comprising: mixing component A with dimethyl sulfoxide at a mass ratio of 1:1, dissolving the mixture at 70°C and 400 r / min under stirring, uniformly mixing, adding tetramethylammonium hydroxide, reacting the ring-opening reaction for 2 h, adding 1,3-bis(3-aminopropyl)tetramethyldisiloxane, reacting the end-capping reaction, and then removing the solvent, water and small molecule organic matter by a vacuum removal process. After 2 h, the phenylsilane-modified aminosiloxane oligomer is obtained.

[0050] Component A comprises: tetramethyltetraphenylcyclotetrasiloxane and octaphenylcyclotetrasiloxane in a mass ratio of 1:1;

[0051] The mass ratio of component A to tetramethylammonium hydroxide is 1:0.02;

[0052] The mass ratio of component A to 1,3-bis(3-aminopropyl)tetramethyldisiloxane is 1:0.3;

[0053] Conditions for the end-capping reaction: react at 70°C for 2 hours, then cool to 46°C and continue the reaction for 2 hours;

[0054] The vacuum removal process is carried out at a temperature of 110℃ and a pressure of -0.096 MPa.

[0055] Example 4: A method for preparing a hydrophobic and anti-corrosion polyurea coating, comprising:

[0056] By weight, 45 parts of polytetrahydrofuran ether diol were dehydrated under vacuum at -0.09 MPa and 100°C for 1 hour. After cooling to below 40°C, 55 parts of cyclohexanedimethyl diisocyanate were added, the temperature was raised to 75°C, and the reaction was carried out for 2 hours. Then the temperature was lowered to 40°C, and 8 parts of phenylsilane-modified aminosiloxane oligomer were added dropwise over 2 hours. The reaction was carried out for another 0.5 hours, and then 10 parts of propylene carbonate were added to obtain the sprayable polyurea component A.

[0057] By weight, 80 parts of polyetheramine D2000, 5 parts of polyetheramine D400, 60 parts of polytetrahydrofuran ether diol, 50 parts of liquid chain extender UNILINK4200 and 1 part of organic bismuth catalyst DY-20 were mixed, the system was heated to 100℃, and the moisture was removed at -0.09 MPa. After 1 hour, the system was cooled to obtain the sprayed polyurea component B.

[0058] The hydrophobic and anti-corrosion polyurea coating comprises: sprayed polyurea component A and sprayed polyurea component B.

[0059] Example 5: A method for preparing a hydrophobic and anti-corrosion polyurea coating, comprising:

[0060] By weight, 45 parts of polytetrahydrofuran ether diol were dehydrated under vacuum at -0.1 MPa and 120°C for 3 hours. After cooling to below 40°C, 55 parts of cyclohexanedimethyl diisocyanate were added, the temperature was raised to 80°C, and the reaction was carried out for 4 hours. Then the temperature was lowered to 50°C, and 8 parts of phenylsilane-modified aminosiloxane oligomer were added dropwise over 4 hours. The reaction was carried out for another hour, and then 5 parts of propylene carbonate were added to obtain the sprayable polyurea component A.

[0061] By weight, 80 parts of polyetheramine D2000, 5 parts of polyetheramine D400, 60 parts of polytetrahydrofuran ether diol, 50 parts of liquid chain extender UNILINK4200 and 1 part of organic bismuth catalyst DY-20 were mixed, the system was heated to 120°C, and the moisture was removed at -0.1 MPa. After 3 hours, the system was cooled to obtain the sprayed polyurea component B.

[0062] The hydrophobic and anti-corrosion polyurea coating comprises: sprayed polyurea component A and sprayed polyurea component B.

[0063] Example 6: A method for preparing a hydrophobic and anti-corrosion polyurea coating, comprising:

[0064] By weight, 45 parts of polytetrahydrofuran ether diol were dehydrated under vacuum at -0.096 MPa and 110°C for 2 hours. After cooling to below 40°C, 55 parts of cyclohexanedimethyl diisocyanate were added, the temperature was raised to 80°C, and the reaction was carried out for 3 hours. Then the temperature was lowered to 45°C, and 8 parts of phenylsilane-modified aminosiloxane oligomer were added dropwise over 3 hours. The reaction was carried out for another 0.8 hours, and then 10 parts of propylene carbonate were added to obtain the sprayable polyurea component A.

[0065] By weight, 80 parts of polyetheramine D2000, 5 parts of polyetheramine D400, 60 parts of polytetrahydrofuran ether diol, 50 parts of liquid chain extender UNILINK4200 and 1 part of organic bismuth catalyst DY-20 were mixed, the system was heated to 110℃, and the moisture was removed at -0.096 MPa. After 2 hours, the system was cooled to obtain the sprayed polyurea component B.

[0066] The hydrophobic and anti-corrosion polyurea coating comprises: sprayed polyurea component A and sprayed polyurea component B.

[0067] Comparative Example 1: A method for preparing a phenylsilane-modified aminosiloxane oligomer, comprising: mixing component A with dimethyl sulfoxide at a mass ratio of 1:1, dissolving the mixture at 70°C and 400 r / min under stirring, uniformly mixing, adding tetramethylammonium hydroxide, reacting the ring-opening reaction for 2 h, adding 1,3-bis(3-aminopropyl)tetramethyldisiloxane, reacting the end-capping reaction, and then removing the solvent, water and small molecule organic matter by a vacuum removal process. After 2 h, the phenylsilane-modified aminosiloxane oligomer is obtained.

[0068] Component A includes: octamethylcyclotetrasiloxane;

[0069] The mass ratio of component A to tetramethylammonium hydroxide is 1:0.02;

[0070] The mass ratio of component A to 1,3-bis(3-aminopropyl)tetramethyldisiloxane is 1:0.3;

[0071] Conditions for the end-capping reaction: react at 70°C for 2 hours, then cool to 46°C and continue the reaction for 2 hours;

[0072] The vacuum removal process is carried out at a temperature of 110℃ and a pressure of -0.096 MPa.

[0073] Comparative Example 2: A method for preparing a phenylsilane-modified aminosiloxane oligomer, comprising: mixing component A with dimethyl sulfoxide at a mass ratio of 1:1, dissolving the mixture at 70°C and 400 r / min under stirring, uniformly mixing, adding tetramethylammonium hydroxide, reacting the ring-opening reaction for 2 h, adding 1,3-bis(3-aminopropyl)tetramethyldisiloxane, reacting the end-capping reaction, and then removing the solvent, water and small molecule organic matter by a vacuum removal process. After 2 h, the phenylsilane-modified aminosiloxane oligomer is obtained.

[0074] Component A comprises: tetramethyltetraphenylcyclotetrasiloxane and octaphenylcyclotetrasiloxane in a mass ratio of 1.2:1;

[0075] The mass ratio of component A to tetramethylammonium hydroxide is 1:0.02;

[0076] The mass ratio of component A to 1,3-bis(3-aminopropyl)tetramethyldisiloxane is 1:0.3;

[0077] Conditions for the end-capping reaction: react at 70°C for 2 hours, then cool to 46°C and continue the reaction for 2 hours;

[0078] The vacuum removal process is carried out at a temperature of 110℃ and a pressure of -0.096 MPa.

[0079] Comparative Example 3: A method for preparing a phenylsilane-modified aminosiloxane oligomer, comprising: mixing component A with dimethyl sulfoxide at a mass ratio of 1:1, dissolving the mixture at 70°C and 400 r / min under stirring, uniformly mixing, adding tetramethylammonium hydroxide, reacting the ring-opening reaction for 2 h, adding 1,3-bis(3-aminopropyl)tetramethyldisiloxane, reacting the end-capping reaction, and then removing the solvent, water and small molecule organic matter by a vacuum removal process. After 2 h, the phenylsilane-modified aminosiloxane oligomer is obtained.

[0080] Component A comprises: tetramethyltetraphenylcyclotetrasiloxane and octaphenylcyclotetrasiloxane in a mass ratio of 1:1.2;

[0081] The mass ratio of component A to tetramethylammonium hydroxide is 1:0.02;

[0082] The mass ratio of component A to 1,3-bis(3-aminopropyl)tetramethyldisiloxane is 1:0.3;

[0083] Conditions for the end-capping reaction: react at 70°C for 2 hours, then cool to 46°C and continue the reaction for 2 hours;

[0084] The vacuum removal process is carried out at a temperature of 110℃ and a pressure of -0.096 MPa.

[0085] Comparative Example 4: A method for preparing a hydrophobic and anti-corrosion polyurea coating, comprising:

[0086] By weight, 45 parts of polytetrahydrofuran ether diol were dehydrated under vacuum at -0.096 MPa and 110°C for 2 hours. After cooling to below 40°C, 55 parts of cyclohexanedimethyl diisocyanate were added, the temperature was raised to 80°C, and the reaction was carried out for 3 hours. Then the temperature was lowered to 45°C, and 8 parts of phenylsilane-modified aminosiloxane oligomer were added dropwise over 3 hours. The reaction was carried out for another 0.8 hours, and then 10 parts of ethylene carbonate were added to obtain the sprayable polyurea component A.

[0087] By weight, 80 parts of polyetheramine D2000, 5 parts of polyetheramine D400, 60 parts of polytetrahydrofuran ether glycol, 50 parts of liquid chain extender UNILINK4200 and 1 part of organic bismuth catalyst DY-20 were mixed, the system was heated to 110℃, and the water was removed at -0.096 MPa. After 2 hours, the temperature was lowered to 45℃, 8 parts of phenylsilane modified aminosiloxane oligomer were added, and the mixture was stirred for another 0.8 hours to obtain the sprayable polyurea component B.

[0088] The hydrophobic and anti-corrosion polyurea coating comprises: sprayed polyurea component A and sprayed polyurea component B.

[0089] Blank Example: A method for preparing a hydrophobic and anti-corrosion polyurea coating, comprising:

[0090] By weight, 45 parts of polytetrahydrofuran ether diol were dehydrated under vacuum at -0.096 MPa and 110°C for 2 hours. After cooling to below 40°C, 55 parts of cyclohexanedimethyl diisocyanate were added, the temperature was raised to 80°C, and the reaction was carried out for 3 hours. Then, the temperature was lowered to 45°C, and 10 parts of propylene carbonate were added to obtain the sprayable polyurea component A.

[0091] By weight, 80 parts of polyetheramine D2000, 5 parts of polyetheramine D400, 60 parts of polytetrahydrofuran ether diol, 50 parts of liquid chain extender UNILINK4200 and 1 part of organic bismuth catalyst DY-20 were mixed, the system was heated to 110℃, and the moisture was removed at -0.096 MPa. After 2 hours, the system was cooled to obtain the sprayed polyurea component B.

[0092] The hydrophobic and anti-corrosion polyurea coating comprises: sprayed polyurea component A and sprayed polyurea component B.

[0093] Experiment: Phenylsilane-modified aminosiloxane oligomers were prepared according to the preparation methods provided in Examples 1-3 and Comparative Examples 1-4, and hydrophobic and anti-corrosion polyurea coatings were prepared according to the preparation methods provided in Examples 4-6, Comparative Example 5 and blank examples.

[0094] Application method: Mix the spray polyurea component A and spray polyurea component B at a volume ratio of 1:1 using a special equipment, and then spray at 65℃ and 20MPa. The average coating thickness is 1.5mm.

[0095] Experiment 1: Physical performance tests were conducted on hydrophobic and anti-corrosion polyurea coatings according to GB / T23446-2009. The test results are shown in Tables 1, 2 and 3.

[0096] Table 1: Physical Properties of the Coating in its Initial State

[0097]

[0098] The hydrophobic and anti-corrosion polyurea coating prepared by the method provided in the blank example has the following physical property test results: tensile strength: 6.45 MPa, elongation at break: 304%.

[0099] As can be seen from the comparison of the test results in Table 1 with the blank example, the phenylsilane-modified aminosiloxane oligomers prepared according to the preparation methods of Examples 1-3 can significantly improve the physical properties of polyurea coatings.

[0100] The experimental results of Comparative Example 1 show that the phenyl group in component A can significantly improve the physical properties of the final coating.

[0101] As can be seen from the experimental results of Examples 3 and 1-2, component A using tetramethyltetraphenylcyclotetrasiloxane and octaphenylcyclotetrasiloxane in a mass ratio of 1:1 is more effective.

[0102] The experimental results of Comparative Examples 2-3 show that the ratio of tetramethyltetraphenylcyclotetrasiloxane to octaphenylcyclotetrasiloxane affects the performance of the final coating.

[0103] As can be seen from the experimental results of Comparative Example 4, the physical properties of the coating actually decreased after adding phenylsilane-modified aminosiloxane oligomer to the sprayed polyurea B component.

[0104] Table 2: Physical properties of the coating after immersion in hot water at 60℃ for 30 days

[0105]

[0106] The test results for the blank example are: tensile strength: 5.68 MPa, elongation at break: 226%.

[0107] As can be seen from the comparison of the test results in Table 1 with the blank example, the phenylsilane-modified aminosiloxane oligomers prepared according to the preparation methods of Examples 1-3 can significantly improve the water resistance of polyurea coatings.

[0108] The test results of Comparative Example 1 show that the phenyl group in component A can significantly improve the water resistance of the final coating.

[0109] As can be seen from the test results of Examples 3 and 1-2, when component A is composed of tetramethyltetraphenylcyclotetrasiloxane and octaphenylcyclotetrasiloxane in a mass ratio of 1:1, the coating has better water resistance.

[0110] The test results of Comparative Examples 2-3 show that the ratio of tetramethyltetraphenylcyclotetrasiloxane to octaphenylcyclotetrasiloxane affects the water resistance of the final coating.

[0111] As can be seen from the test results of Comparative Example 4, the water resistance of the coating actually decreased after adding phenylsilane-modified aminosiloxane oligomer to the sprayed polyurea B component.

[0112] Table 3: Physical properties of the coating after 2000 hours of artificial climate aging treatment

[0113]

[0114] The irradiance of the artificial climate aging treatment is 60 W / m. 2 .

[0115] The test results for the blank example are: tensile strength: 5.59 MPa, elongation at break: 241%.

[0116] As can be seen from the comparison of the test results in Table 1 with the blank example, the phenylsilane-modified aminosiloxane oligomers prepared according to the preparation methods of Examples 1-3 can significantly improve the aging resistance of polyurea coatings.

[0117] As can be seen from the test results of Comparative Example 1, the phenyl group in component A can significantly improve the aging resistance of the final coating.

[0118] As can be seen from the test results of Examples 3 and 1-2, when component A is composed of tetramethyltetraphenylcyclotetrasiloxane and octaphenylcyclotetrasiloxane in a mass ratio of 1:1, the coating exhibits better aging resistance.

[0119] The test results of Comparative Examples 2-3 show that the ratio of tetramethyltetraphenylcyclotetrasiloxane to octaphenylcyclotetrasiloxane affects the aging resistance of the final coating.

[0120] As can be seen from the test results of Comparative Example 4, the aging resistance of the coating actually decreased after adding phenylsilane-modified aminosiloxane oligomer to the sprayed polyurea B component.

[0121] Experiment 2: Coating Contact Angle Experiment

[0122] Droplets were placed on the coating surface. After the droplets stabilized, the contact angle between the droplets and the solid surface was observed and recorded using a contact angle meter. The test results are shown in Table 4.

[0123] Table 4

[0124]

[0125] The test results for the blank example were: contact angle 70.7°.

[0126] As can be seen from the comparison of the test results in Table 1 with the blank example, the phenylsilane-modified aminosiloxane oligomers prepared according to the preparation methods of Examples 1-3 can significantly improve the hydrophobicity of polyurea coatings.

[0127] As can be seen from the experimental results of Comparative Example 1, the phenyl group in component A can significantly improve the hydrophobic properties of the final coating.

[0128] As can be seen from the test results of Examples 3 and 1-2, when component A is composed of tetramethyltetraphenylcyclotetrasiloxane and octaphenylcyclotetrasiloxane in a mass ratio of 1:1, the hydrophobic properties of the coating are better.

[0129] The experimental results of Comparative Examples 2-3 show that the ratio of tetramethyltetraphenylcyclotetrasiloxane to octaphenylcyclotetrasiloxane affects the hydrophobic properties of the final coating.

[0130] As can be seen from the experimental results of Comparative Example 4, the hydrophobic properties of the coating actually decreased after adding phenylsilane-modified aminosiloxane oligomer to the sprayed polyurea B component.

[0131] Experiment 3: 2000-hour salt spray experiment

[0132] The hydrophobic and anti-corrosion polyurea coatings were tested according to GB / T1771-2007 "Determination of resistance to neutral salt spray in paints and varnishes". The test results are shown in Table 5.

[0133] Table 5

[0134]

[0135] This indicates severe blistering, cracking, and peeling. This indicates the presence of minor blistering, cracking, and peeling. This indicates the presence of bubbles and cracks.

[0136] As can be seen from the test results of Examples 1-6, the hydrophobic and anti-corrosion polyurea coating provided by the present invention has good anti-corrosion performance.

[0137] The test results of Comparative Example 1 show that the phenyl group in component A can significantly improve the corrosion resistance of the final coating.

[0138] The test results of Comparative Examples 2-3 show that the ratio of tetramethyltetraphenylcyclotetrasiloxane to octaphenylcyclotetrasiloxane affects the corrosion resistance of the final coating.

[0139] As can be seen from the experimental results of Comparative Example 4, although the anti-corrosion performance of the coating is also excellent after adding phenylsilane-modified aminosiloxane oligomer to the sprayed polyurea component B, the physical properties are reduced to a certain extent. Therefore, in the preparation method provided by the present invention, phenylsilane-modified aminosiloxane oligomer is added only to component A.

[0140] The above are merely preferred embodiments of the present invention and are not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing a phenylsilane-modified aminosiloxane oligomer, characterized in that, include: Tetramethylammonium hydroxide was added to component A for ring-opening reaction, followed by the addition of 1,3-bis(3-aminopropyl)tetramethyldisiloxane for end-capping reaction, and then the phenylsilane-modified aminosiloxane oligomer was obtained by vacuum removal process. The general structural formula of component A is as shown in formula ( As shown in the image: Mode( ) Wherein, R1~R8 are selected from phenyl or alkyl, and at least one is phenyl. Component A includes: conforming to formula ( One or more compounds with the structure ) The mass ratio of component A to tetramethylammonium hydroxide is 1: (0.01~0.03). The ring-opening reaction is carried out at a temperature of 60-85°C for 1-3 hours.

2. The preparation method according to claim 1, wherein component A comprises: One or more of tetramethyltetraphenylcyclotetrasiloxane and octaphenylcyclotetrasiloxane.

3. The preparation method according to claim 1, characterized in that, The mass ratio of component A to 1,3-bis(3-aminopropyl)tetramethyldisiloxane is 1:(0.2~0.5).

4. The preparation method according to any one of claims 1 to 3, characterized in that, The conditions for the end-capping reaction are: react at 60~85℃ for 1~3h, then cool down to 40~50℃ and continue the reaction for 1~3h.

5. The preparation method according to claim 4, characterized in that, The vacuum removal process is carried out at a temperature of 100~120℃ and a vacuum degree of -0.09~-0.1 MPa.

6. A phenylsilane-modified aminosiloxane oligomer prepared by the preparation method according to any one of claims 1 to 5.

7. A method for preparing a hydrophobic and anti-corrosion polyurea coating, characterized in that, include: After the polyether reacts with the diisocyanate, the phenylsilane-modified aminosiloxane oligomer of claim 6 is added dropwise. After the reaction is complete, an active diluent is added to obtain the sprayable polyurea component A. After mixing polyetheramine, polyether, chain extender and catalyst, the sprayable polyurea component B is obtained; The hydrophobic and anti-corrosion polyurea coating comprises: sprayed polyurea component A and sprayed polyurea component B.

8. The preparation method according to claim 7, characterized in that, The polyether is vacuum dehydrated at -0.09 to -0.1 MPa and 100 to 120°C for 1 to 3 hours. After cooling to below 40°C, diisocyanate is added, and the temperature is raised to 75 to 85°C. The reaction is carried out for 2 to 4 hours, and then the temperature is lowered to 40 to 50°C. Phenylsilane-modified aminosiloxane oligomer is added dropwise over 2 to 4 hours. The reaction is then carried out for another 0.5 to 1 hour, and finally an active diluent is added to obtain the sprayable polyurea component A.

9. The preparation method according to claim 7, characterized in that, After mixing polyetheramine, polyether, chain extender and catalyst, the system is heated to 100~120℃, and moisture is removed at -0.09~-0.1 MPa. After 1~3 hours, the temperature is lowered to obtain the sprayable polyurea B component.

10. A hydrophobic and anti-corrosion polyurea coating prepared by the preparation method according to any one of claims 7 to 9.

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