CN106243798B - A kind of dual cure F-Si hydrophobic coating material and preparation method thereof - Google Patents

Abstract

The invention provides a dual-curing fluoro-silicon hydrophobic coating material and a preparation method thereof. The dual-curing fluoro-silicon hydrophobic coating material is prepared according to the following steps: 1) Vinyl triethoxysilane, silicon dioxide, silane Mix the coupling agent and acrylic acid evenly, then add fluorocarbon resin and solvent and mix evenly to obtain the mixture; wherein, the mass percentage of silicon dioxide in the mixture is 5.2%~7.6%, and vinyltriethoxysilane, The mass ratio of silicon dioxide and acrylic acid is 3.5~4.5:1:5.5~6.5; 2) Add defoamer, dispersant and wetting agent to the above mixture and mix evenly, grind, and add The isocyanate curing agent and the photoinitiator are uniformly mixed to obtain a spray coating; the spray coating is sprayed, exposed, and dried to obtain a hydrophobic coating material. The hydrophobic coating material of the invention has both good adhesion and hydrophobic properties, and the preparation method is simple, the process conditions are mild, no expensive and complicated equipment is needed, and it is suitable for industrial production.

Description

A kind of dual curing fluoro-silicon hydrophobic coating material and preparation method thereof

technical field

The invention relates to a hydrophobic coating material and a preparation method thereof, in particular to a dual-cured fluorosilicon hydrophobic coating material and a preparation method thereof.

Background technique

Hydrophobic coatings generally refer to coatings with a static contact angle of water on the surface of the coating greater than 90°. When the static contact angle of water on the surface of the hydrophobic coating is greater than 150°, the coating is called a superhydrophobic coating. At present, the existing hydrophobic coatings have multiple functions, such as self-cleaning, anti-icing, anti-pollution, anti-corrosion, waterproof, etc., which can meet different market needs. Sensors and other fields have very broad application prospects.

At present, the preparation methods of hydrophobic materials mainly include: electrochemical method, phase separation method, template method, sol-gel method, electrospinning technology, vapor deposition method, layer-by-layer self-assembly method, etc. However, the above method is not only complicated in process, but also requires expensive equipment and harsh process conditions, making it difficult to carry out large-scale industrial production and cannot be really applied. It is a relatively common method to spray the prepared hydrophobic spray liquid evenly on the substrate to form a hydrophobic coating by the spray coating method, but the coating obtained by this method has poor adhesion and is prone to peeling off. Reduced hydrophobicity. Therefore, it is of great significance to develop a preparation method with simple process and good coating adhesion.

Contents of the invention

The purpose of the present invention is to provide a dual-cured fluoro-silicon hydrophobic coating material and its preparation method to solve the problem of complex preparation process of existing hydrophobic coating materials, harsh process conditions, expensive instruments and equipment and poor coating adhesion. The problem.

The purpose of the present invention is achieved like this:

A dual curing fluorosilicon hydrophobic coating material is prepared according to the following steps:

1) Mix vinyltriethoxysilane, silicon dioxide, silane coupling agent and acrylic acid evenly, then add fluorocarbon resin and solvent and mix evenly to obtain a mixture; wherein, silicon dioxide accounts for the mass percentage of the mixture 5.2% to 7.6%, and the mass ratio of vinyltriethoxysilane, silicon dioxide and acrylic acid is 3.5 to 4.5:1:5.5 to 6.5;

2) Add defoamer, dispersant and wetting agent to the above mixture and mix evenly, grind, add isocyanate curing agent and photoinitiator to the material after grinding, and mix evenly to get spray paint; spray the obtained The coating is sprayed, exposed, and dried to obtain a dual-cured fluorosilicon hydrophobic coating material.

In the dual-cure fluorosilicon hydrophobic coating material of the present invention, the isocyanate curing agent is an IPDI trimer, and the amount of the IPDI trimer is calculated according to formula (I),

In the formula, OHV is the hydroxyl value of fluorocarbon resin, mgKOH/g; 42 is the relative molecular weight of NCO; NCO is the isocyanate value of IPDI trimer; the value of NCO/OH is 1.1.

In the dual-cure fluorosilicon hydrophobic coating material of the present invention, the silane coupling agent is KH-570.

In the dual-cure fluorosilicon hydrophobic coating material of the present invention, the amount of the photoinitiator is 2% to 2.5% of the sum of the mass of vinyltriethoxysilane, acrylic acid and silane coupling agent. The initiator includes a photoinitiator TPO and a photoinitiator 184, and the mass ratio of the photoinitiator TPO to the photoinitiator 184 is 1˜1.5:1.

In the dual-cure fluorosilicon hydrophobic coating material of the present invention, the mass percentage of the silicon dioxide in the mixture is preferably 7.0% to 7.6%, and the mass ratio of vinyltriethoxysilane, silicon dioxide and acrylic acid is Preferably 4:1:6, the particle size of the silica is 10-50mm.

In the dual-cured fluorosilicon hydrophobic coating material of the present invention, the exposure time is 25s, and the drying temperature is 140°C.

In the dual-cure fluorosilicon hydrophobic coating material of the present invention, the solvent is at least one of xylene or butyl acetate.

In the dual-curing fluorosilicon hydrophobic coating material of the present invention, the defoamer is a silicone oil defoamer, the dispersant is a modified polyurethane, and the wetting agent is an ionic wetting agent.

The hydrophobic coating material of the present invention has both good adhesion and hydrophobic properties, and its contact angle to water can reach more than 150°, and can be widely used in the fields of power transmission wires, insulators, power towers, aerospace and the like.

The present invention also provides a method for preparing a dual-cured fluorosilicon hydrophobic coating material, comprising the following steps:

a. Mix vinyltriethoxysilane, silicon dioxide, silane coupling agent and acrylic acid, and stir until uniform, then add fluorocarbon resin and solvent, and continue stirring to obtain a mixture; among them, silicon dioxide accounts for The mass percentage of the material is 5.2% to 7.6%, preferably 7.0% to 7.6%, and the mass ratio of vinyltriethoxysilane, silicon dioxide and acrylic acid is 4:1:6;

b. Add defoamer, wetting agent and dispersant to the above mixture, grind the material after stirring for 4-6 hours, add isocyanate curing agent and photoinitiator to the ground material, mix evenly, and spray the coating;

c. Spraying, exposing and drying the above-mentioned spray paint to obtain a dual-cured fluorosilicon hydrophobic coating material.

In step a of the method of the present invention, the mass percentage of the silicon dioxide in the mixture is 7.0% to 7.6%, and the mass ratio of vinyltriethoxysilane, silicon dioxide and acrylic acid is 4:1:6.

In step a of the method of the present invention, the particle size of the silicon dioxide is 10-50 mm, the silane coupling agent is KH-570, and the solvent is at least one of xylene or butyl acetate.

In step b of the method of the present invention, the isocyanate curing agent is an IPDI trimer, and the amount of the IPDI trimer is calculated according to formula (I), and the photoinitiator includes photoinitiator TPO and photoinitiator 184, the amount of the photoinitiator is 2% to 2.5% of the sum of the mass of vinyltriethoxysilane, acrylic acid and silane coupling agent, and the mass ratio of the photoinitiator TPO to photoinitiator 184 1～1.5:1,

In the formula, OHV is the hydroxyl value of fluorocarbon resin, mgKOH/g; 42 is the relative molecular weight of NCO; NCO is the isocyanate value of IPDI trimer; the value of NCO/OH is 1.1.

In step b of the method of the present invention, the defoamer is a silicone oil defoamer, the dispersant is a modified polyurethane, and the wetting agent is an ionic wetting agent.

In step c of the method of the present invention, the exposure time is 25s, and the drying temperature is 140°C.

The present invention obtains a hydrophobic material with both high hydrophobicity and high adhesion through a dual curing method of photocuring and chemical curing. The method of the invention has simple operation, mild process conditions, no expensive and complex equipment, low cost, high practicability, and is suitable for large-scale industrial production.

Description of drawings

Fig. 1 is the water contact angle test result graph of the coating material prepared in Example 1.

Fig. 2 is a diagram showing the test results of the water contact angle of the coating material prepared in Example 2.

FIG. 3 is a graph showing the test results of the water contact angle of the coating material prepared in Example 3. FIG.

Fig. 4 is a graph showing the test results of the water contact angle of the coating material prepared in Example 4.

Fig. 5 is the sample surface comparison diagram of the coating materials produced in Example 4 and Comparative Example 1, wherein a is the sample plate made in Example 4, and b is the sample plate made in Comparative Example 1.

Detailed ways

Example 1

Add 13.144g of vinyltriethoxysilane, 3.286g of SiO ₂ , 0.6g of silane coupling agent KH-570 and 19.716g of acrylic acid into a four-necked flask for high-speed mechanical stirring for 20min, then add 26g of fluorocarbon resin and 1g of butyl acetate , continue to stir for 10min, then add 0.1g defoamer, 0.066g dispersant and 0.06g wetting agent to it, keep stirring at high speed for 4h to obtain the mixture, put the obtained mixture into a conical mill for grinding; Add 3.3g isophorone diisocyanate (IPDI) trimer and 0.432gTPO and 0.288g184 in the mixture, mix uniformly, get spray paint, spray paint on the tinplate that has been cleaned by spraying mode, make The sample was exposed for 25s and dried at 140°C to obtain a dual-cured fluorosilicon hydrophobic coating material.

The hydrophobic angle of the obtained coating material was tested, and the test results are shown in Figure 1, and the contact angle was 108.4°.

Example 2

Add 13.04g of vinyltriethoxysilane, 3.3g of SiO ₂ , 0.45g of silane coupling agent KH-570 and 19.572g of acrylic acid into a four-neck flask for high-speed mechanical stirring for 20min, then add 9.3g of fluorocarbon resin and 1g of butyl acetate Esters, continue to stir for 10min, then add 0.068g defoamer, 0.065g dispersant and 0.05g wetting agent, keep stirring at high speed for 4h to obtain the mixture, put the obtained mixture into a conical mill for grinding; Add 1.19g isophorone diisocyanate (IPDI) trimer and 0.432gTPO and 0.288g184 in the final mixture, mix uniformly, get spray paint, spray paint is coated on the tinplate that has been cleaned with the mode of spray coating, make Obtain a model, expose for 25s, and dry at 140°C to obtain a dual-cured fluorine-silicon hydrophobic coating material.

The hydrophobic angle of the obtained coating material was tested, and the test results are shown in Figure 2, and the contact angle was 150.3°.

Example 3

Add 13.109g of vinyltriethoxysilane, 3.278g of SiO ₂ , 0.4g of silane coupling agent KH-570 and 19.7g of acrylic acid into a four-neck flask for high-speed mechanical stirring for 20min, then add 6g of fluorocarbon resin and 2g of butyl acetate , continue to stir for 10min, then add 0.06g defoamer, 0.065g dispersant and 0.04g wetting agent to it, keep stirring at high speed for 4h to obtain the mixture, put the obtained mixture into a conical mill for grinding; Add 0.076g isophorone diisocyanate (IPDI) trimer and 0.399gTPO and 0.265g184 in the mixture, mix uniformly, get spray coating, spray coating to be coated on the tinplate that has been cleaned by spray coating, make The sample was exposed for 25s and dried at 140°C to obtain a dual-cured fluorosilicon hydrophobic coating material.

The hydrophobic angle of the obtained coating material was tested, and the test results are shown in Figure 3, and the contact angle was 152.6°.

Example 4

Add 13.108g of vinyltriethoxysilane, 3.277g of SiO ₂ , 0.3g of silane coupling agent KH-570 and 19.663g of acrylic acid into a four-neck flask for high-speed mechanical stirring for 20min, then add 5g of fluorocarbon resin and 2g of butyl acetate , continue to stir for 10min, then add 0.06g defoamer, 0.066g dispersant and 0.04g wetting agent to it, keep stirring at high speed for 4h to obtain the mixture, put the obtained mixture into the conical mill for grinding; Add 0.633g isophorone diisocyanate (IPDI) trimer and 0.397gTPO and 0.264g184 in the mixture, mix uniformly, get spray coating, spray coating to be coated on the tinplate that has been cleaned by spray coating, make The sample was exposed for 25s and dried at 140°C to obtain a dual-cured fluorosilicon hydrophobic coating material. The surface of the obtained coating material was smooth without peeling off, as shown in a in Figure 5.

The hydrophobic angle of the obtained coating material was tested, and the test results are shown in Figure 4, and the contact angle was 153°.

Example 5

Add 11.55g of vinyltriethoxysilane, 3.3g of SiO ₂ , 0.45g of silane coupling agent KH-570 and 21.45g of acrylic acid into a four-necked flask for high-speed mechanical stirring for 20min, then add 9.3g of fluorocarbon resin and 1g of butyl acetate Esters, continue to stir for 10min, then add 0.068g defoamer, 0.065g dispersant and 0.05g wetting agent, keep stirring at high speed for 4h to obtain the mixture, put the obtained mixture into a conical mill for grinding; Add 1.19g isophorone diisocyanate (IPDI) trimer and 0.418gTPO and 0.418g184 in the mixture after, mix uniformly, get spray coating, spray coating is coated on the cleaned tinplate with the mode of spray coating, make Obtain a model, expose for 25s, and dry at 140°C to obtain a dual-cured fluorine-silicon hydrophobic coating material.

The hydrophobic angle of the obtained coating material was tested, and the contact angle was 143.5°.

Example 6

Add 14.747g of vinyltriethoxysilane, 3.277g of SiO ₂ , 0.3g of silane coupling agent KH-570 and 21.301g of acrylic acid into a four-necked flask for high-speed mechanical stirring for 20min, then add 5g of fluorocarbon resin and 2g of butyl acetate , continue to stir for 10min, then add 0.06g defoamer, 0.066g dispersant and 0.04g wetting agent to it, keep stirring at high speed for 4h to obtain the mixture, put the obtained mixture into the conical mill for grinding; Add 0.633g isophorone diisocyanate (IPDI) trimer and 0.436gTPO and 0.291g184 to the mixture, mix uniformly, get spray coating, spray coating to be coated on the tinplate that has been cleaned by spray coating, make The sample was exposed for 25s and dried at 140°C to obtain a dual-cured fluorosilicon hydrophobic coating material.

The hydrophobic angle test was carried out on the obtained coating material, and its contact angle was 150°.

Comparative example 1

Add 1.5g of SiO ₂ , 0.24g of silane coupling agent KH-570 and 16g of butyl acetate into a four-necked flask for high-speed mechanical stirring for 20 minutes, then add 6g of fluorocarbon resin, continue stirring for 10 minutes, and then add 0.04g of defoamer , 0.09g dispersant and 0.02g wetting agent, keep stirring at a high speed for 4h to obtain the mixture, put the obtained mixture into a conical mill and grind; then add 0.98g isophorone diisocyanate (IPDI ) trimer, mixed evenly to obtain a spray coating, which was sprayed onto the cleaned tinplate to prepare a sample, and dried at 140°C to obtain a fluorosilicon hydrophobic coating material. There is a large amount of silica powder on the surface of the obtained coating material, and there is a large area of peeling off, which cannot be attached to the tinplate substrate, as shown in b in Figure 5.

Claims (10)

1. A dual curing fluorosilicon hydrophobic coating material is characterized in that it is prepared according to the following steps: 1) Mix vinyltriethoxysilane, silicon dioxide, silane coupling agent and acrylic acid evenly, then add fluorocarbon resin and solvent and mix evenly to obtain a mixture; among them, silicon dioxide accounts for the mass percentage of the mixture 5.2%~7.6%, and the mass ratio of vinyltriethoxysilane, silicon dioxide and acrylic acid is 3.5~4.5:1:5.5~6.5; 2) Add defoamer, dispersant and wetting agent to the above mixture and mix evenly, grind, add isocyanate curing agent and photoinitiator to the ground material, and mix evenly to get spray paint; spray the obtained The coating is sprayed, exposed, and dried to obtain a dual-cured fluorosilicon hydrophobic coating material. 2. The dual-curing fluorosilicon hydrophobic coating material according to claim 1, wherein the isocyanate curing agent is IPDI trimer, and the silane coupling agent is KH-570. 3. dual curing fluorosilicon hydrophobic coating material according to claim 1, is characterized in that, the consumption of described photoinitiator is vinyltriethoxysilane, acrylic acid and silane coupling agent three quality summation 2%~2.5%. 4. according to claim 1 and 3 described dual curing fluorosilicon hydrophobic coating materials, it is characterized in that, described photoinitiator comprises photoinitiator TPO and photoinitiator 184, the composition of described photoinitiator TPO and photoinitiator 184 The mass ratio is 1~1.5:1. 5. The dual-cured fluorosilicon hydrophobic coating material according to claim 1, wherein the silicon dioxide accounts for 7.0% to 7.6% by mass of the mixture, and vinyltriethoxysilane, two The mass ratio of silicon oxide and acrylic acid is 4:1:6. 6. The dual-curing fluorosilicon hydrophobic coating material according to claim 1, characterized in that the exposure time is 25s, and the drying temperature is 140°C. 7. A method for preparing a dual-cure fluorosilicon hydrophobic coating material, comprising the following steps: a. Mix vinyltriethoxysilane, silicon dioxide, silane coupling agent and acrylic acid, and stir until uniform, then add fluorocarbon resin and solvent, and continue stirring to obtain a mixture; among them, silicon dioxide accounts for The mass percentage of the material is 5.2%~7.6%, and the mass ratio of vinyltriethoxysilane, silicon dioxide and acrylic acid is 3.5~4.5:1:5.5~6.5; b. Add defoamer, wetting agent and dispersant to the above mixture, grind the material after stirring for 4~6 hours, add isocyanate curing agent and photoinitiator to the ground material, mix evenly, and spray coating; c. Spraying, exposing and drying the above-mentioned spray paint to obtain a dual-cured fluorosilicon hydrophobic coating material. 8. The preparation method of dual curing fluorosilicon hydrophobic coating material according to claim 7, characterized in that, in step a, the silicon dioxide accounts for 7.0%~7.6% by mass of the mixture, and the vinyl The mass ratio of triethoxysilane, silicon dioxide and acrylic acid is 4:1:6. 9. the preparation method of dual curing fluorosilicon hydrophobic coating material according to claim 7, is characterized in that, in step b, described isocyanate curing agent is IPDI trimer, and described photoinitiator is photoinitiator TPO and photoinitiator 184, the consumption of described photoinitiator is 2%～2.5% of the sum of three mass of vinyltriethoxysilane, acrylic acid and silane coupling agent, and described photoinitiator TPO and photoinitiator The mass ratio of 184 is 1~1.5:1. 10. The preparation method of dual-curing fluorosilicon hydrophobic coating material according to claim 7, characterized in that, in step c, the exposure time is 25s, and the drying temperature is 140°C.