CN108441085A - A kind of aqueous super-amphiphobic long lasting anticorrosion coating and preparation method thereof - Google Patents

Abstract

The invention discloses a preparation method of a water-based super-amphiphobic long-lasting anti-corrosion coating, which is obtained by sequentially spraying a water-based epoxy bottom layer and a water-based super-amphiphobic surface layer on the surface of a metal base; wherein the water-based epoxy bottom layer is made of water-based epoxy resin , water-based epoxy curing agent, nano filler and anti-rust pigment; the water-based super amphiphobic surface layer is composed of fluorine-containing silicone polymer, fluorine-containing silane modified nanoparticles and fluorocarbon surfactant. The coating exhibits excellent anti-corrosion, super-amphiphobic and stability through the synergistic effect of the water-based epoxy bottom layer and the water-based super-amphiphobic surface layer. , Oil-water separation and other fields gradually show good development prospects.

Description

A kind of water-based super-amphiphobic long-acting anti-corrosion coating and preparation method thereof

technical field

The invention relates to the preparation of an anti-corrosion coating, in particular to a water-based super-amphiphobic long-acting anti-corrosion coating and a preparation method thereof.

Background technique

Corrosion is a phenomenon in which metal materials undergo chemical or electrochemical interactions with surrounding media to cause damage or deterioration, resulting in huge economic losses and waste of resources. In order to minimize the loss caused by metal corrosion, coating protection methods are mainly used at present. There are many methods of metal surface coating protection, such as anti-corrosion coatings, coatings, phosphating, passivation, etc. Due to the strong requirements of environmental protection regulations, traditional metal coating protection and surface treatment methods are facing severe challenges.

In recent years, inspired by the "lotus leaf effect" in nature, superhydrophobic surfaces have attracted widespread attention from the scientific and industrial circles due to their unique structural features and self-cleaning properties. It gradually shows good development prospects in the fields of anti-corrosion, surface self-cleaning, anti-fog, anti-frost, fluid drag reduction, and oil-water separation. In particular, superhydrophobic surfaces have great application prospects in the fields of corrosion and protection. This is due to the micro-nano rough structure and low surface energy substances of the super-hydrophobic surface, which can lock a thin layer of air between the solid-liquid interface, thereby reducing the contact area and residence time of the corrosive liquid on the coating surface, It makes it difficult for corrosive liquids to penetrate into the coating to achieve the purpose of anticorrosion. However, superhydrophobic surfaces are easily polluted by corrosive liquids with low surface energy, which in turn causes the adhesion of corrosive liquids on the surface, resulting in the loss of superhydrophobic properties and poor anticorrosion effect.

A superamphiphobic surface refers to a solid surface with both water and oil contact angles greater than 150°. This superhydrophobic and superoleophobic surface has very attractive application prospects in terms of corrosion resistance, self-cleaning, oil resistance, and drag reduction. It can make up for the deficiency that superhydrophobic surfaces are easily wetted by low surface energy liquids. aroused great interest. In recent years, there are only a few reports on the application of superamphiphobic coatings in anticorrosion. CN105238207 discloses a super-amphiphobic conductive multifunctional anti-corrosion coating, CN201410641342.1 discloses a super-amphiphobic coating with durable anti-corrosion and wear resistance and its preparation method, and CN201710152672.8 discloses a fluorine-silicon modified Super amphiphobic anti-corrosion coating of permanent epoxy resin. These patented technologies involve the preparation and application of super-amphiphobic anti-corrosion coatings, but a large amount of organic solvents are used in the preparation process, complex process routes are adopted, and there are problems such as environmental pollution and high cost. In addition, there are also problems such as general anticorrosion effect and poor stability.

Contents of the invention

The purpose of the present invention is to provide a water-based super-amphiphobic long-lasting anti-corrosion coating and a preparation method thereof for the problems existing in the existing super-amphiphobic anti-corrosion coating.

1. Preparation of water-based super-amphiphobic long-term anti-corrosion coating

The preparation method of the water-based super-amphiphobic long-acting anti-corrosion coating of the present invention is obtained by successively spraying a water-based epoxy bottom layer and a water-based super-amphiphobic surface layer on the surface of a metal substrate; wherein the water-based epoxy bottom layer is composed of water-based epoxy resin, water-based epoxy It is composed of curing agent, nano filler and antirust pigment; the water-based super amphiphobic surface layer is composed of fluorine-containing silicone polymer, fluorine-containing silane modified nanoparticles and fluorocarbon surfactant. Its specific preparation process is as follows

(1) Preparation of water-based epoxy primer

Raw material components (by mass percentage): 40-65% water-based epoxy resin, 5-15% water-based epoxy curing agent, 0.5-5% nano filler, 5-15% anti-rust pigment, and the balance is water.

Wherein the nano filler is at least one of silicon dioxide, titanium dioxide, talcum powder, bentonite or hectorite; the antirust pigment is at least one of zinc phosphate, aluminum tripolyphosphate and zinc aluminum phosphate.

Preparation process: Add water, nano fillers, and anti-rust pigments in sequence to water-based epoxy resin, stir at high speed to disperse evenly, grind until the fineness is less than 10um, then add water-based epoxy curing agent and stir evenly to obtain water-based epoxy primer; then put The water-based epoxy primer is sprayed onto the surface of the metal substrate by spraying, and cured at room temperature for 12-48 hours to obtain a water-based epoxy primer.

The metal base is stainless steel or aluminum alloy, and the spraying thickness of the water-based epoxy primer on the surface of the metal base is 20-30 μm.

(2) Preparation of the water-based super amphiphobic surface layer

Raw material components (by mass percentage): 1-5% of fluorine-containing silicone polymer, 0.5-5% of fluorine-containing silane-modified nanoparticles, 0.1-1% of fluorocarbon surfactant, and the rest is water.

The fluorine-containing silicone polymers are perfluorooctyltrimethoxysilane, perfluorooctyltriethoxysilane, perfluorodecyltrimethoxysilane, perfluorodecyltriethoxysilane, perfluorooctyl Dimethylmethoxysilane, perfluorodecyldimethylmethoxysilane; the organosilane is ethoxy, methoxy, vinyl, amino, epoxy, methacryloxy, mercapto or at least one of ureidosilanes.

The preparation method of fluorine-containing silane modified nanoparticles is: ultrasonically disperse the nanoparticles and fluorine-containing silane in water at a mass ratio of 1:1~1:10, and add acid as a catalyst (the amount of acid added is 0.1%~2% Volume fraction), obtained by stirring and reacting at room temperature for 24~48h. The nanoparticles are at least one of silicon dioxide, titanium dioxide, zinc oxide, montmorillonite, and attapulgite; the fluorine-containing silanes are perfluorooctyltrimethoxysilane, perfluorooctyltriethoxysilane, Fluorodecanyltrimethoxysilane, perfluorodecyltriethoxysilane, perfluorooctyldimethylmethoxysilane, perfluorodecyldimethylmethoxysilane; acid catalysts are hydrochloric acid, acetic acid, oxalic acid at least one of the

Preparation process: Disperse fluorine-containing silicone polymer, fluorine-containing silane-modified nanoparticles and surfactants into water to obtain a stable water-based superamphiphobic coating suspension, and then spray it on the above-mentioned water-based epoxy bottom layer and cure at room temperature 12~48h, the water-based super-amphiphobic long-lasting anti-corrosion coating was prepared. The spraying thickness of the water-based super-amphiphobic surface layer is 10-30 μm.

2. Performance test of super amphiphobic long-term anti-corrosion coating

1. Super amphiphobic properties

Test method: use the German Dataphysics contact angle measuring instrument OCA20 to measure the contact angle and rolling angle of different surface energy liquids (5µL) on the coating surface.

Test results: The super-amphiphobic effect of the water-based super-amphiphobic anti-corrosion coating is shown in Figure 1. It shows that the anticorrosion coating prepared by the present invention has a good superamphiphobic property with a contact angle of more than 150° to water, diiodomethane, hexadecane, dodecane, and decane, and a rolling angle of less than 10°.

2. Corrosion resistance

Test method: According to GB/T 1771-2007, the concentration of sodium chloride in the test box is 5%, the temperature is 35°C, and the pH of the solution is 6.5~7.2.

Test results: The corrosion resistance effect of the water-based super amphiphobic anti-corrosion coating is shown in Figure 2. It shows that after 1500h neutral salt spray test, the surface of the water-based super amphiphobic anti-corrosion coating has no change, and the surface still maintains good super-amphiphobic properties, indicating that the coating has excellent long-term anti-corrosion performance.

Description of drawings

Fig. 1 is the superamphiphobic effect diagram of the waterborne superamphiphobic long-lasting anticorrosion coating prepared by the present invention.

Fig. 2 is the effect diagram of the corrosion resistance of the water-based superamphiphobic long-lasting anticorrosion coating prepared in the present invention.

Detailed ways

The preparation and performance of the water-based super-amphiphobic long-lasting anti-corrosion coating of the present invention will be further described through specific examples below.

Example 1

(1) Preparation of water-based epoxy layer

Raw material ratio (by mass percentage): 50% water-based epoxy resin, 10% water-based epoxy curing agent, 2% bentonite, 10% zinc phosphate, and the rest is water.

Preparation process: first disperse the water-based epoxy resin solution into water, then add bentonite and zinc phosphate in sequence, stir at high speed for 30 minutes to fully disperse it, grind it to less than 2.5um, then add water-based epoxy curing agent, stir evenly at high speed, and then spray onto 100×150cm steel plate (coating thickness is 20~25μm), cured at room temperature for 24h to prepare water-based epoxy primer.

(2) Preparation of water-based superamphiphobic surface layer

Raw material ratio (by mass percentage): perfluorooctyltrimethoxysilane 5%, perfluorodecyltriethoxysilane modified silica nanoparticles 1%, fluorocarbon surfactant 1%, the rest for water.

Preparation process: Disperse perfluorooctyltrimethoxysilane, fluorine-containing silane-modified nanoparticles, and fluorocarbon surfactants into water to obtain a water-based super-amphiphobic coating suspension; then the water-based super-amphiphobic coating suspension Spray on the water-based epoxy primer (coating thickness is 10-20μm), and cure at room temperature for 24 hours to obtain a water-based super amphiphobic long-lasting anti-corrosion coating.

(3) Performance test of water-based superamphiphobic surface layer

The contact angle of the coating to hexadecane is 156°, and the rolling angle is 5°; after 1000 hours of neutral salt spray resistance test, there is no rust and bubbling phenomenon on the surface, and it still maintains a good super amphiphobic property.

Example 2

(1) Preparation of water-based epoxy primer

Raw material ratio (by mass percentage): 40% water-based epoxy resin, 15% water-based epoxy curing agent, 3% talcum powder, 5% aluminum tripolyphosphate, and the rest is water.

Preparation process: Disperse the water-based epoxy resin solution into water, then add talcum powder and aluminum tripolyphosphate in turn, stir at high speed for 30 minutes to fully disperse it, then grind until the fineness is less than 1um, then add water-based epoxy curing agent, and stir evenly at high speed After that, it is sprayed onto a steel plate of 100×150cm (the thickness of the coating is 20-25μm), and cured at room temperature for 32 hours to obtain a water-based epoxy layer.

(2) Preparation of water-based superamphiphobic surface layer

Raw material ratio (by mass percentage): 3% perfluorodecyltrimethoxysilane, 2% attapulgite nanoparticles modified by perfluorodecyltrimethoxysilane, 0.5% fluorocarbon surfactant, and the rest is water.

Preparation process: disperse perfluorodecyltrimethoxysilane, attapulgite nanoparticles modified by perfluorodecyltrimethoxysilane, fluorine-containing silane modified nanoparticles, and fluorocarbon surfactants into aqueous solution to obtain aqueous Super-amphiphobic coating suspension; then spray the water-based super-amphiphobic coating suspension on the water-based epoxy bottom layer (coating thickness is 20~30μm), and cure at room temperature for 24 hours to obtain a water-based super-amphiphobic long-lasting anti-corrosion coating .

(3) Performance test of water-based superamphiphobic surface layer

The contact angle of the coating to hexadecane is 153°, and the rolling angle is 6°; after 1200 hours of neutral salt spray resistance test, there is no rust and bubbling phenomenon on the surface, and it still maintains a good super amphiphobic property.

Example 3

(1) Preparation of water-based epoxy primer

Raw material ratio (by mass percentage): 50% water-based epoxy resin, 15% water-soluble epoxy curing agent, 2% hectorite, 10% zinc phosphate, and the rest is water.

Preparation process: first disperse the water-based epoxy resin solution into water, then add hectorite and zinc phosphate in turn, stir at high speed for 30 minutes to make it fully dispersed, and the grinding fineness is less than 5um, then add water-based epoxy curing agent, and stir evenly at high speed Afterwards, it is sprayed onto a 100×150cm steel plate (the thickness of the coating is 20-30μm), and cured at room temperature for 24 hours to obtain a water-based epoxy layer.

(2) Preparation of water-based superamphiphobic surface layer

Raw material ratio (by mass percentage): 2% perfluorodecyldimethylmethoxysilane, 3% titanium dioxide nanoparticles modified by perfluorooctyltriethoxysilane, 1% fluorocarbon surfactant, The rest is water.

Preparation process: Disperse perfluorodecyldimethylmethoxysilane, perfluorooctyltriethoxysilane modified titanium dioxide nanoparticles, and fluorocarbon surfactants into aqueous solution to obtain a water-based superamphiphobic coating suspension liquid. Finally, the water-based super-amphiphobic coating suspension was sprayed on the water-based epoxy bottom layer (the thickness of the coating was 15-25 μm), and cured at room temperature for 24 hours to obtain a water-based super-amphiphobic long-lasting anti-corrosion coating.

(3) Performance test of water-based superamphiphobic surface layer

The contact angle of the coating to hexadecane is 156°, and the rolling angle is 4°; after 1600 hours of neutral salt spray resistance test, there is no rust bubbling phenomenon on the surface, and it still maintains a good super amphiphobic property.

Example 4

(1) Preparation of water-based epoxy layer

Raw material ratio (by mass percentage): 60% water-based epoxy resin, 10% water-soluble epoxy curing agent, 3% silicon dioxide, 10% aluminum tripolyphosphate, and the rest is water.

Preparation process: first disperse the water-based epoxy resin solution into water, then add silicon dioxide and aluminum tripolyphosphate in turn, stir at high speed for 30 minutes to fully disperse it, grind it to a fineness of less than 1um, then add water-based epoxy curing agent, high-speed After stirring evenly, spray it on a 100×150cm steel plate (the thickness of the coating is 20~25μm), and cure at room temperature for 32 hours; a water-based epoxy layer is obtained.

(2) Preparation of water-based superamphiphobic surface layer

Raw material ratio (by mass percentage): 3% perfluorooctyldimethylmethoxysilane, 2% zinc oxide nanoparticles modified by perfluorooctyltrimethoxysilane, 0.6% fluorocarbon surfactant, The rest is water.

Preparation process: Disperse perfluorooctyldimethylmethoxysilane, zinc oxide nanoparticles modified by perfluorooctyltrimethoxysilane, and fluorocarbon surfactants in water to obtain an aqueous superamphiphobic coating suspension ; Then spray the water-based super-amphiphobic coating suspension on the water-based epoxy bottom layer (the coating thickness is 10-20 μm), and cure at room temperature for 48 hours to obtain a water-based super-amphiphobic long-lasting anti-corrosion coating.

(3) Performance test of water-based superamphiphobic surface layer

The contact angle of the coating to hexadecane is 155°, and the rolling angle is 5°; after 1800 hours of neutral salt spray resistance test, there is no rust and bubbling phenomenon on the surface, and it still maintains a good super amphiphobic property.

In each of the above examples, the preparation method of fluorine-containing silane modified nanoparticles is as follows: ultrasonically disperse the corresponding nanoparticles and fluorine-containing silane in water at a mass ratio of 1:1 to 1:10, and add acid as a catalyst (acid The addition amount is 0.1%~2% volume fraction), and it is obtained by stirring and reacting at room temperature for 24~48h. Wherein the acid catalyst is hydrochloric acid, acetic acid or oxalic acid.

Claims (10)

1. a kind of preparation method of aqueous super-amphiphobic long lasting anticorrosion coating, is to spray water-base epoxy bottom successively in metal substrate surface Layer, aqueous super-amphiphobic face layer and obtain；Wherein water-base epoxy bottom is by aqueous epoxy resins, aqueous epoxy curing agent, Nano filling It is formed with rust resisting pigment；Aqueous super-amphiphobic face layer is by fluoro organosilicon polymer, fluorine containing silane modified Nano particle and fluorine carbon table Face activating agent composition.

2. the preparation method of aqueous super-amphiphobic long lasting anticorrosion coating as described in claim 1, it is characterised in that：The water-base epoxy Bottom is completed by the raw material components and technique of following mass percent：

Raw material components：Aqueous epoxy resins 40 ~ 65%, aqueous epoxy curing agent 5 ~ 15%, Nano filling 0.5 ~ 5%, rust resisting pigment 5 ~ 15%, surplus is water；

Preparation process：Water, Nano filling, rust resisting pigment are sequentially added in aqueous epoxy resins, after high-speed stirred is uniformly dispersed It is milled to fineness and is less than 10um, add aqueous epoxy curing agent and stir evenly to obtain water-base epoxy bottom material；Then by water-base epoxy bottom Material sprays to metal substrate surface by spraying method, and water-base epoxy bottom is made in 12 ~ 48h of room temperature curing.

3. the preparation method of aqueous super-amphiphobic long lasting anticorrosion coating as claimed in claim 1 or 2, it is characterised in that：The nanometer Filler is at least one of silica, titanium dioxide, talcum powder, bentonite or hectorite.

4. the preparation method of aqueous super-amphiphobic long lasting anticorrosion coating as claimed in claim 1 or 2, it is characterised in that：The antirust Pigment is at least one of trbasic zinc phosphate, aluminium triphosphate, zinc aluminophosphate.

5. the preparation method of aqueous super-amphiphobic long lasting anticorrosion coating as claimed in claim 1 or 2, it is characterised in that：Water-base epoxy The coating thickness of bottom is 20 ~ 30 μm.

6. the preparation method of aqueous super-amphiphobic long lasting anticorrosion coating as described in claim 1, it is characterised in that：It is described aqueous super double The face of dredging layer is completed by the raw material components and technique of following mass percent：

Raw material components：Fluoro organosilicon polymer 1 ~ 5%, fluorine containing silane modified Nano particle 0.5 ~ 5%, fluorocarbon surfactant 0.1 ~ 1%, remaining is water；

Preparation process：By in fluoro organosilicon polymer, fluorine containing silane modified Nano particle and surfactant-dispersed to water, obtain It to stable aqueous super-amphiphobic wash coat suspension, is then sprayed on above-mentioned water-base epoxy bottom, 12 ~ 48h of normal temperature cure, is made Aqueous super-amphiphobic long lasting anticorrosion coating.

7. the preparation method of aqueous super-amphiphobic long lasting anticorrosion coating as claimed in claim 1 or 6, it is characterised in that：It is described fluorine-containing Organosilicon polymer be perfluoro capryl trimethoxy silane, perfluoro capryl triethoxysilane, perfluoro decyl trimethoxy silane, Perfluoro decyl triethoxysilane, perfluoro capryl dimethyl methoxy silane, perfluoro decyl dimethyl methoxy silane；It is described to have Machine silane be ethyoxyl, methoxyl group, vinyl, amino, epoxy group, methacryloxy, sulfydryl or ureido silane in extremely Few one kind.

8. the preparation method of aqueous super-amphiphobic long lasting anticorrosion coating as claimed in claim 1 or 6, it is characterised in that：It is described fluorine-containing The preparation of silane-modified nano-particle is by corresponding nano-particle and fluorine containing silane by 1:1~1:10 quality compares ultrasonic disperse Yu Shuizhong is added acid and is used as catalyst, reaction 24 ~ 48h times are stirred at room temperature and obtain；Wherein nano-particle is titanium dioxide At least one of silicon, titanium dioxide, zinc oxide, montmorillonite, attapulgite；Fluorine containing silane is perfluoro capryl trimethoxy silicon Alkane, perfluoro capryl triethoxysilane, perfluoro decyl trimethoxy silane, perfluoro decyl triethoxysilane, perfluoro capryl two Methylmethoxysilane, perfluoro decyl dimethyl methoxy silane；Acid catalyst is at least one of hydrochloric acid, acetic acid, oxalic acid； The addition of acid catalyst is 0.1 ~ 2%.

9. the preparation method of aqueous super-amphiphobic long lasting anticorrosion coating as claimed in claim 1 or 6, it is characterised in that：It is described aqueous The coating thickness of super-amphiphobic face layer is 10 ~ 30 μm.

10. the preparation method of aqueous super-amphiphobic long lasting anticorrosion coating as described in claim 1, it is characterised in that：The Metal Substrate Bottom is stainless steel or aluminium alloy.