CN115197630A

CN115197630A - High-solid low-viscosity ship hull paint and preparation method thereof

Info

Publication number: CN115197630A
Application number: CN202210942298.2A
Authority: CN
Inventors: 梁又绿; 梁新方
Original assignee: Baishikunyu Energy Technology Chengdu Co ltd
Current assignee: Guangdong Paint Color New Material Co ltd
Priority date: 2022-08-08
Filing date: 2022-08-08
Publication date: 2022-10-18
Anticipated expiration: 2042-08-08
Also published as: CN115197630B

Abstract

The invention discloses high-solid low-viscosity ship hull paint and a preparation method thereof, and relates to the technical field of coating compositions. The invention is prepared by taking coal tar pitch, mica powder, talcum powder, solvent and epoxy resin as main raw materials and adding a dispersant, a flatting agent and a modified anti-settling agent. The high-solid low-viscosity ship hull paint prepared by the invention has lower viscosity and good construction performance; the ship hull paint has good thixotropic property by adding the modified anti-settling agent. During the stirring process of the high-solid low-viscosity ship hull paint before construction, the shearing stress can easily destroy the entanglement between short fluorocarbon chains and the hydrogen bond interaction of amino and hydroxyl, so that the fluidity of the ship primer is strong during mixing, and the dispersion of each component is facilitated; after spraying, under a static condition, a continuous and compact hydrogen bond network and fluorocarbon chain entanglement are formed in the ship primer, all fillers in the coating matrix are stabilized, free low molecules or free fillers in the coating are reduced, and the cured paint film has good stability and excellent corrosion resistance.

Description

High-solid low-viscosity ship hull paint and preparation method thereof

Technical Field

The invention relates to the technical field of coating compositions, and particularly relates to high-solid low-viscosity ship hull paint and a preparation method thereof.

Background

The high-solid ship primer has high solid content ratio, so the produced paint has high viscosity and poor fluidity, is difficult to extend on the surface of a substrate, generates more pore defects due to poor rheological property of the coating, and is difficult to prepare a continuous high-barrier film. The wetting dispersant is added into the paint vehicle, so that the dispersion efficiency of paint components can be improved, and the aim of reducing the viscosity of a high-solid system is fulfilled. However, the anti-sagging performance of the paint is reduced when the viscosity of the system is reduced, and the paint with lower viscosity is partially gathered due to the influence of gravity and the like after being sprayed due to the shape specificity of the hull, so that the thickness of the paint film is uneven, and defects are easily generated in the curing process.

Chinese patent CN 102876229A discloses a water-resistant ship primer which is prepared from the following raw materials: 2-3 parts of mesolite, 10-12 parts of titanium dioxide, 40-50 parts of ester glue varnish, 1-2 parts of zinc oxide, 10-14 parts of china clay, 8-10 parts of No. 200 solvent gasoline and 10-12 parts of lime rosin, and has excellent water resistance and strong adhesive force. Chinese patent CN 106118299A provides a preparation method of graphene capsaicin synthetic ship primer, and the wear resistance of the ship primer is improved by adding graphene; the ship primer contains capsaicin, so that the functions of resisting bacteria and expelling marine attached organisms are achieved. The ship primer does not optimize the defect of paint sagging in the construction process, and the protection effect of the ship primer is reduced due to the fact that the thickness of a paint film is uneven in practical application.

Disclosure of Invention

In view of the above-mentioned drawbacks of the prior art, the problem to be solved by the present invention is to provide a high-solid low-viscosity ship hull paint with good construction operability and biosorption resistance, and a preparation method thereof.

A preparation method of a high-solid low-viscosity ship hull paint comprises the following steps of:

s1, mixing 15-45 parts of coal tar pitch, 6-12 parts of mica powder, 10-17.5 parts of talcum powder and 10-20 parts of composite solvent under a heating condition to obtain an asphalt mixture for later use;

s2, continuously adding 25-50 parts of epoxy resin, 3-6 parts of dispersing agent, 0.8-1.6 parts of flatting agent and 1.5-2.5 parts of modified anti-settling agent into the asphalt mixture, and mixing until all components are uniformly dispersed to obtain the high-solid low-viscosity ship hull paint.

Preferably, the coal tar pitch in step S1 is low-temperature coal tar pitch, and has a softening point of 40 to 75 ℃.

Preferably, the mica powder in step S1 has a size of 200 to 400 mesh.

Preferably, the size of the talcum powder in step S1 is 200-400 meshes.

Preferably, the composite solvent in step S1 is xylene and cyclohexanone in a mass ratio of 1-3: 1, and (b) a mixture.

Preferably, the temperature of the mixing in step S1 is 105 to 130 ℃.

Preferably, the dispersant in step S2 is any one of BYK dispersant W966, BYK dispersant 108, BYK dispersant 164, BYK dispersant 170, BYK dispersant 2150, and BYK dispersant 9076.

Preferably, the leveling agent in step S2 is any one of a basf leveling agent 3522, a basf leveling agent 3580, a basf leveling agent 3650, a basf leveling agent 3886, and a basf leveling agent 7411.

In order to solve the problems of the high-solid low-viscosity ship hull paint and improve the comprehensive performance of a paint film, the invention prepares the modified anti-settling agent. The modified anti-settling agent takes graphene oxide as a raw material, and amino and fluorocarbon chains are introduced through modification. The graphene oxide sheet layer is combined with the ship hull paint, so that the permeation resistance and the scratch resistance of the ship hull paint can be enhanced, and the adverse effect caused by pore defects in a high-solid system can be reduced.

The invention uses aminopropyltriethoxysilane for hydrolysis, and then reacts and connects with abundant hydroxyl on the surface of graphene oxide, thereby solving the technical problems that graphene oxide sheets are easy to gather in a polymer matrix and have poor compatibility with a polymer material due to strong interlayer interaction between layered nano sheets, and improving the dispersion of the graphene oxide sheets in a ship hull paint matrix. According to the invention, bromine is introduced into graphene oxide through an esterification reaction with 2-bromo-2-methylpropanoyl bromide, the bromine is then substituted by a condensation product of sodium perfluorovalerate and aminocaproic acid, and an extra amino and fluorocarbon chain is introduced into the graphene oxide, so that the modified anti-settling agent with self-thixotropy performance is obtained. The modified anti-settling agent mainly forms a hydrogen bond network through the attraction of amino and hydroxyl, and the well-dispersed modified anti-settling agent improves the integrity of a coating through blocking air holes and defects, prolongs the diffusion path of corrosive substances to a substrate, and prolongs the protection time of a ship primer to the substrate. Due to the fact that the long alkyl chain is introduced into the graphene oxide, the interfacial bonding capacity between the graphene oxide and the ship primer is improved.

Preferably, the preparation method of the modified anti-settling agent is as follows:

m1, carrying out ultrasonic dispersion on graphene oxide, absolute ethyl alcohol and water to obtain a graphene oxide suspension; adding aminopropyltriethoxysilane into the graphene oxide suspension, heating and carrying out hydrolysis reaction; after the hydrolysis reaction is finished, centrifugally separating the suspension to obtain a solid crude product, and washing, washing and drying the crude product with water and alcohol to obtain a black solid product for later use;

m2, taking the black solid product to disperse in N, N-dimethylformamide to obtain a reaction suspension; adding 4-dimethylaminopyridine, triethylamine and 2-bromo-2-methylpropanoyl bromide into the reaction suspension, and carrying out esterification reaction under an anaerobic condition; after the esterification reaction is finished, centrifugally separating the suspension to obtain a solid crude product, and washing, washing and drying the crude product with water and alcohol to obtain modified graphene oxide for later use;

m3, mixing sodium perfluorovalerate, aminocaproic acid and tetrahydrofuran to obtain a reaction mixed solution; adding a condensing agent into the reaction mixed solution and carrying out condensation reaction under an anaerobic condition; after the condensation reaction is finished, removing the solvent tetrahydrofuran to obtain a reaction crude product, and re-dissolving, recrystallizing and drying the crude product to obtain a condensation product for later use;

m4, mixing the modified graphene oxide, the condensation product and N, N-dimethylformamide under an anaerobic condition, and then adding pentamethyldiethylenetriamine and copper bromide to react; and after the reaction is finished, centrifuging to collect a solid product, washing the product with alcohol, and drying to obtain the modified anti-settling agent.

Specifically, the preparation method of the modified anti-settling agent comprises the following steps of:

m1, performing ultrasonic dispersion on 0.1-0.2 part of graphene oxide, 60-75 parts of absolute ethyl alcohol and 20-25 parts of water to obtain a graphene oxide suspension; adding 0.75-1 part of aminopropyltriethoxysilane into the graphene oxide suspension, heating and carrying out hydrolysis reaction; after the hydrolysis reaction is finished, centrifugally separating the suspension to obtain a solid crude product, washing the crude product with water, washing with alcohol, and drying to obtain a black solid product for later use;

m2, dispersing 0.1-0.2 part of the black solid product in 2-5 parts of N, N-dimethylformamide to obtain a reaction suspension; adding 0.1-0.15 part of 4-dimethylamino pyridine, 0.05-0.1 part of triethylamine and 1.5-3 parts of 2-bromo-2-methylpropionyl bromide into the reaction suspension, and carrying out esterification reaction under an anaerobic condition; after the esterification reaction is finished, centrifugally separating the suspension to obtain a solid crude product, and washing, washing and drying the crude product with water and alcohol to obtain modified graphene oxide for later use;

m3, mixing 2-3 parts of sodium perfluorovalerate, 1-1.5 parts of aminocaproic acid and 10-15 parts of tetrahydrofuran to obtain a reaction mixed solution; adding 0.05-0.2 part of condensing agent into the reaction mixed solution and carrying out condensation reaction under an anaerobic condition; after the condensation reaction is finished, removing solvent tetrahydrofuran to obtain a reaction crude product, and redissolving, recrystallizing and drying the crude product to obtain a condensation product for later use;

m4, mixing 0.5-1 part of the modified graphene oxide, 3.5-8 parts of the condensation product and 75-100 parts of N, N-dimethylformamide under an anaerobic condition, and then adding 0.0001-0.0002 part of pentamethyl diethylenetriamine and 0.1-0.225 part of copper bromide for reaction; and after the reaction is finished, centrifugally collecting a solid product, washing the product with alcohol, and drying to obtain the modified anti-settling agent.

Preferably, the temperature of the ultrasonic dispersion in the step M1 is 0-4 ℃, the frequency is 28-40 kHz, the power is 550-800W, and the treatment time is 15-30 min. .

Preferably, the temperature of the hydrolysis reaction in the step M1 is 75-90 ℃, and the reaction time is 6-12 h.

Preferably, the reaction temperature of the esterification reaction in the step M2 is 65-80 ℃, and the reaction time is 6-18 h.

Preferably, in the step M3, the condensing agent is any one of dicyclohexylcarbodiimide, diisopropylcarbodiimide, 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide, and 2- (7-azabenzotriazole) -N, N' -tetramethylurea hexafluorophosphate.

Preferably, the condensation reaction in the step M3 is carried out at a temperature of 0-25 ℃ for 0.5-2 h.

Preferably, the reaction temperature in the step M4 is 75-85 ℃, and the reaction time is 12-24 h.

The curing method of the high-solid low-viscosity ship hull paint comprises the following steps:

selecting a corresponding commercial curing agent according to the type of the commercial epoxy resin selected by the high-solid low-viscosity hull paint, mixing the high-solid low-viscosity hull paint and the curing agent according to the proportion of the product specification, spraying the mixture on the surface of a matrix, and curing for 0.5-12 h at normal temperature.

The sprayed ship primer forms a continuous and compact hydrogen bond network inside under a static condition, stabilizes each filler in a coating substrate, reduces free low molecules or free fillers in the coating, and ensures that the uniformity and the corrosion resistance of a cured paint film are better. After the fluorocarbon chain is introduced, the surface free energy of the ship primer is reduced, and the pollutant adhesion of the ship in the running process can be reduced; in the fluorocarbon chain, as the Van der Waals radius of the fluorine atoms is smaller than that of the hydrogen atoms, the fluorocarbon chain forms a slightly twisted spiral conformation, the entanglement density is higher, and the stability after the ship primer is sprayed can be further improved by combining with a hydrogen bond network. In the stirring process, the fluorocarbon chains introduced by the sodium perfluorovalerate are short, and the shearing stress can easily destroy the entanglement and hydrogen bond interaction between molecular chains, so that the fluidity of the ship primer is strong during the mixing operation in the preparation process, and the dispersion of each component is facilitated.

On the basis of the common general knowledge in the field, the above preferred conditions can be combined randomly to obtain the preferred embodiments of the invention.

The introduction and the function of part of raw materials in the formula of the invention are as follows:

coal tar pitch: the residue obtained after the distillation processing of the coal tar to remove the liquid fraction belongs to one of artificial asphalts, is generally viscous liquid, semisolid or solid, is black and glossy, generally contains 92 to 94 percent of carbon and 4 to 5 percent of hydrogen. The coating is suitable for being used as waterproof coating and protective layer of steel structure, concrete and masonry outdoors and can be coated and painted outdoors at normal temperature.

Mica powder: non-metallic minerals containing a plurality of components, mainly SiO ₂ The content is about 49% in general, and Al ₂ O ₃ The content is about 30 percent. The mica powder has good elasticity and toughness. The additive has the characteristics of insulativity, high temperature resistance, acid and alkali resistance, corrosion resistance, strong adhesive force and the like, and is an excellent additive. It is widely used in the industries of electric appliances, welding electrodes, rubber, plastics, paper making, paint, coating, pigment, ceramics, cosmetics, novel building materials and the like, and has extremely wide application.

Talc powder: the magnesium silicate mineral talc family talc is prepared by pulverizing hydrous magnesium silicate as main ingredient, treating with hydrochloric acid, washing with water, and drying. Is commonly used as filler of plastic and paper products, rubber filler and anti-sticking agent of rubber products, high-grade paint coating and the like. Has excellent physical and chemical properties such as lubricity, fire resistance, acid resistance, insulativity, high melting point, chemical inactiveness, good covering power, softness, good luster, strong adsorption power and the like.

And (3) graphene oxide: the graphene oxide is brown yellow, and the common products in the market are in powder, flake and solution forms. After oxidation, the oxygen-containing functional groups on the graphene are increased, so that the graphene is more active than graphene in property, and the properties of the graphene can be improved through various reactions with the oxygen-containing functional groups.

The invention has the beneficial effects that:

compared with the prior art, the modified anti-settling agent is added into the high-solid low-viscosity ship hull paint, and the anti-settling agent takes graphene oxide as a raw material and introduces amino and fluorocarbon chains through modification; the graphene oxide sheet layer is combined with the ship hull paint, so that the permeation resistance and the scratch resistance of the ship hull paint can be enhanced, and the adverse effect caused by pore defects in a high-solid system can be reduced.

Compared with the prior art, the modified anti-settling agent prepared by the invention solves the technical problems that graphene oxide sheets are easy to gather in a polymer matrix and have poor compatibility with a polymer material due to strong interlayer interaction among the layered nano sheets, and improves the dispersion of the graphene oxide sheets in a ship hull paint matrix.

Compared with the prior art, in the stirring process of the ship primer, the fluorocarbon chains of the modified anti-settling agent are shorter, and the shearing stress can easily destroy the entanglement and hydrogen bond interaction between molecular chains, so that the ship primer has strong fluidity during mixing operation and is beneficial to the dispersion of all components; after spraying, under a static condition, a continuous and compact hydrogen bond network is formed inside the ship primer, each filler in the coating substrate is stabilized, and free low molecules or free fillers in the coating are reduced, so that the uniformity and the corrosion resistance of the cured paint film are better.

Detailed Description

The invention is further illustrated by the following examples, which are not intended to limit the invention thereto. Experimental procedures without specifying specific conditions in the following examples were selected in accordance with conventional procedures and conditions, or in accordance with commercial instructions.

Some raw material parameters in the comparative examples and examples of the invention are as follows:

low-temperature coal tar pitch with a softening point of 50 ℃ provided by Hebei Fengtai energy science and technology limited;

epoxy 6101, available from Tokyo Stationery environmental protection technology Co., ltd;

epoxy curing agent MH-112, available from Changsha Xingda chemical industry Co., ltd;

the graphene oxide layer is 0.5-1.2 nm in thickness and 4-7 mu m in diameter and is provided by Hangzhou Zhi titanium purification technology Co., ltd;

hamming moded Bentonite Bengel-828, supplied by Sichuan Kaiban chemical materials Co.

Example 1

A preparation method of high-solid low-viscosity ship hull paint comprises the following steps:

s1, mixing 35kg of low-temperature coal tar pitch with 9kg of mica powder, 12.5kg of talcum powder and 15kg of composite solvent at 120 ℃ to obtain an asphalt mixture for later use;

s2, continuously adding 45kg of epoxy resin 6101,4kg of BYK dispersant W966 and 1.5kg of basf leveling agent 3522 into the asphalt mixture, and mixing until the components are uniformly dispersed to obtain the high-solid low-viscosity ship hull paint.

The specification of the mica powder in the step S1 is 400 meshes; the specification of the talcum powder in the step S1 is 400 meshes.

In the step S1, the composite solvent is xylene and cyclohexanone in a mass ratio of 3:1, and (b) a mixture.

Example 2

A preparation method of a high-solid low-viscosity ship hull paint comprises the following steps:

s2, adding 45kg of epoxy resin 6101,4kg of BYK dispersant W966, 1.5kg of Pasteur leveling agent 3522 and 2kg of Hamming modest bentonite BENGEL-828 into the asphalt mixture, and mixing until the components are uniformly dispersed to obtain the high-solid low-viscosity ship hull paint.

In the step S1, the composite solvent is xylene and cyclohexanone in a mass ratio of 3:1 of the mixture formed.

Example 3

and S2, continuously adding 45kg of epoxy resin 6101,4kg of BYK dispersing agent W966, 1.5kg of basf leveling agent 3522 and 2kg of modified anti-settling agent into the asphalt mixture, and mixing until all components are uniformly dispersed to obtain the high-solid low-viscosity ship hull paint.

The preparation method of the modified anti-settling agent comprises the following steps:

m1, carrying out ultrasonic dispersion on 0.1kg of graphene oxide, 60kg of absolute ethyl alcohol and 20kg of deionized water to obtain graphene oxide suspension; adding 0.75kg of aminopropyltriethoxysilane into the graphene oxide suspension, heating and carrying out hydrolysis reaction; after the hydrolysis reaction is finished, centrifugally separating the suspension to obtain a solid crude product, washing the crude product for 3 times by using deionized water, washing the crude product for 3 times by using absolute ethyl alcohol, and drying to obtain a black solid product for later use;

m2, taking 0.1kg of the black solid product and dispersing in 3kg of N, N-dimethylformamide to obtain a reaction suspension; adding 0.1kg of 4-dimethylaminopyridine, 0.05kg of triethylamine and 1.5kg of 2-bromo-2-methylpropanoyl bromide into the reaction suspension, and carrying out esterification reaction under the protection of nitrogen; and after the esterification reaction is finished, centrifugally separating the suspension to obtain a solid crude product, washing the crude product for 3 times by using deionized water, washing the crude product for 3 times by using absolute ethyl alcohol, and drying to obtain the modified anti-settling agent.

The temperature of the ultrasonic dispersion in the step M1 is 0 ℃, the frequency is 40kHz, the power is 550W, and the processing time is 15min.

The temperature of the hydrolysis reaction in the step M1 is 85 ℃, and the reaction time is 9h.

The reaction temperature of the esterification reaction in the step M2 is 75 ℃, and the reaction time is 12h.

Example 4

s2, continuously adding 45kg of epoxy resin 6101,4kg of BYK dispersant W966, 1.5kg of basf leveling agent 3522 and 2kg of modified anti-settling agent into the asphalt mixture, and mixing until the components are uniformly dispersed to obtain the high-solid low-viscosity ship hull paint.

m2, taking 0.1kg of the black solid product and dispersing in 3kg of N, N-dimethylformamide to obtain a reaction suspension; adding 0.1kg of 4-dimethylamino pyridine, 0.05kg of triethylamine and 1.5kg of 2-bromo-2-methylpropanoyl bromide into the reaction suspension, and carrying out esterification reaction under the protection of nitrogen; after the esterification reaction is finished, centrifugally separating the suspension to obtain a solid crude product, washing the crude product for 3 times by using deionized water, washing the crude product for 3 times by using absolute ethyl alcohol, and drying to obtain modified graphene oxide for later use;

m3, mixing 2kg of sodium perfluorovalerate, 1kg of aminocaproic acid and 10kg of tetrahydrofuran to obtain a reaction mixed solution; adding 0.05kg of dicyclohexylcarbodiimide into the reaction mixed solution and carrying out condensation reaction under the protection of nitrogen; after the condensation reaction is finished, removing solvent tetrahydrofuran to obtain a reaction crude product, and redissolving, recrystallizing and drying the crude product to obtain a condensation product for later use;

m4, under the protection of nitrogen, mixing 0.5kg of the modified graphene oxide, 3.5kg of the condensation product and 75kg of N, N-dimethylformamide, and then adding 0.0001kg of pentamethyldiethylenetriamine and 0.1kg of copper bromide for reaction; and after the reaction is finished, centrifugally collecting a solid product, washing the product for 3 times by using absolute ethyl alcohol, and drying to obtain the modified anti-settling agent.

The condensation reaction in step M3 was carried out at 5 ℃ for 1.5h.

The reaction temperature in the step M4 is 80 ℃, and the reaction time is 18h.

Before the painting operation, the high-solid low-viscosity ship hull paint prepared in examples 1 to 4 was stirred at a speed of 120rpm for 15min, then sprayed on the surface of a substrate, the thickness of the primer was 80 μm, and cured for 6h in an environment with a temperature of 25 ℃ and a relative humidity of 50% to obtain corresponding paint film samples.

Test example 1

The viscosity of the high-solid low-viscosity hull paint under static conditions and under shear stress stirring conditions is respectively tested. The stirring process is carried out at a speed of 120rpm for 15min. The viscosity is measured in accordance with the specific procedures of the national standard GB/T1723-1993 "paint viscometry". The test adopts a coating-4 viscometer, the test temperature is 25 ℃, and the test scheme adopts a method B according to the standard. Each group of test is repeated twice, the difference of the two measured values is not more than 3 percent of the average value, and the average value of the two measured values is taken as the test result. The results of the viscosity test of the high solids low viscosity hull are shown in table 1.

TABLE 1

The viscosity of the high-solid low-viscosity paint in a static state (coating-4 cup/25 ℃) is between 80 and 100 s; as can be seen from the test results in Table 1, the viscosities of examples 1 to 4 in the static state meet the above requirements. Under the action of shear stress, thixotropy shown by each example has certain difference, the viscosity of the example added with the commercial anti-settling agent and the modified anti-settling agent is reduced after stirring, the viscosity change of the example 4 is the largest, and the viscosity of the high-solid low-viscosity ship hull paint of the example 4 is reduced in the stirring process, so that the dispersion of each component is facilitated; the viscosity of the paint is higher under a static condition, and the paint is favorable for maintaining the stability of a paint film after being sprayed on the surface of a matrix, and local aggregation caused by the action of environmental factors is avoided. The reason for this phenomenon may be that, during the stirring process, the fluorocarbon chains of the modified anti-settling agent are shorter, and the shear stress can easily destroy the entanglement and hydrogen bond interaction between the molecular chains, so that the fluidity of the ship primer is strong during the mixing operation during the preparation process, which is beneficial to the dispersion of each component; under the static condition after spraying, continuous and compact hydrogen bond networks are formed by amino and hydroxyl in the ship primer, and all fillers in the coating matrix are stabilized.

Test example 2

The algae resistance test of the high-solid low-viscosity ship hull paint is carried out according to the specific requirements in the national standard GB/T21353-2008 'paint film algae resistance test method'. The test medium was Allen medium, as required in the above standard; the test strain is Chlorella vulgaris (Chlorella vulgaris) ATCC 11468; in the preparation of a paint film, a steel sheet panel with the thickness of 1mm is selected as a carrier, small blocks with the size of 2.8cm multiplied by 2.8cm are cut, the surface of the small blocks is roughened by abrasive paper, the surface of the carrier is subjected to oil stain cleaning treatment by alcohol, and 3 samples are prepared for each group. Placing the inoculated sample into a constant-temperature constant-humidity illumination incubator, wherein the temperature is 25 ℃, the relative humidity is 85 percent, the illumination intensity is 3000lx, and the illumination is carried out for 14 hours every day; keeping the surface of the sample wet, and recording the growth conditions of the sample and the algae in the culture dish; the culture was continued for 21 days, and the test results were checked and recorded. After the test is finished, the growth condition of algae on the surface of the paint film is observed by naked eyes, the degree of the algae growing on the surface of the sample is evaluated according to the grade in the table 2, and the culture method, the test algae species, the illumination time and the test period adopted by the test are reported. The results of the algae resistance test of the high solids low viscosity hull paint are shown in table 3.

TABLE 2

TABLE 3

Name (R)	Grade of
		Example 1	4
Example 2	3
		Example 3	2
Example 4	0

As can be seen from the definitions in table 2, the lower the algae resistance rating, the better the algae resistance of the boat primer. As can be seen from the results in table 3, example 4 has the best anti-algal properties. The reason for this may be that the modified anti-settling agent introduces additional amino and fluorocarbon chains into the graphene oxide, and these well-dispersed modified anti-settling agents improve the integrity of the coating by blocking pores and defects, prolonging the diffusion path of corrosive substances to the substrate, while the surface free energy of the ship primer decreases after the fluorocarbon chains are introduced, which may reduce the adhesion of algae.

Test example 3

The salt water resistance of the high-solid low-viscosity ship hull paint is tested by referring to the specific steps in the national standard GB/T10834-2008 'method for determining salt water resistance of ship paint and soaking in hot salt water'. Adopting a saline solution constant temperature test tank, wherein all parts in contact with test saline are made of plastics; the size of the test tank is 700mm multiplied by 400mm, and the test tank is provided with a cover and a constant temperature heating system; the size of the test plate is 300mm multiplied by 100mm multiplied by 2mm, and four test plates are prepared for each group; the distance between the sample in the soaking tank and the inner wall of the tank is 40mm.

Hot saline water soaking is selected for testing, the temperature of the saline water is 37 ℃, soaking is carried out for 7d for one period, and a hot saline water soaking test with the temperature of 82 ℃ is carried out in the last 2h of each period; the test was performed for 12 cycles. And (3) detecting the phenomena of light loss, color change, rusting, bubbling, falling, cracks and the like of a coating system by referring to a national standard GB/T1766-2008 'rating method for color paint and varnish coating aging'. The results of the salt water resistance test of the high-solid low-viscosity hull paint are shown in table 4.

TABLE 4

Name (R)	Grade of degree of change	Grade of number of damage	Destruction size rating
				Example 1	4	4	S3
Example 2	3	3	S3
				Example 3	2	2	S2
Example 4	0	0	S1

According to the judgment definition in the national standard GB/T1766-2008 'rating method for paint and varnish coating aging', the lower the grade is, the more excellent the salt water resistance is. As can be seen from the test results of table 4, example 4 has the best brine resistance, which may occur because the graphene oxide sheets of the modified anti-settling agent are combined with the ship hull paint, which is advantageous in reducing the adverse effects of void defects in the high solids system, and can enhance the permeation resistance of the ship hull paint. After the high-solid low-viscosity ship hull paint containing the modified anti-settling agent is sprayed, a hydrogen bond network is formed through the attraction of amino and hydroxyl, the structure of the fluorocarbon chain is stable and has good chemical resistance, meanwhile, the fluorocarbon chain forms a slightly-twisted spiral conformation, the entanglement density is high, air holes and defects are blocked by combining with the hydrogen bond network, the integrity of the coating is improved, and the diffusion path of corrosive substances to a substrate is prolonged.

Claims

1. A preparation method of a high-solid low-viscosity ship hull paint comprises the following steps of:

s2, continuously adding 25-50 parts of epoxy resin, 3-6 parts of dispersing agent, 0.8-1.6 parts of flatting agent and 1.5-2.5 parts of modified anti-settling agent into the asphalt mixture, and uniformly mixing to obtain the high-solid low-viscosity ship hull paint.

2. The method for preparing a high-solid low-viscosity ship hull paint as claimed in claim 1, wherein: the coal tar pitch in the step S1 is low-temperature coal tar pitch, and the softening point is 40-75 ℃; in the step S1, the composite solvent is xylene and cyclohexanone in a mass ratio of 1-3: 1 of the mixture formed.

3. The method for preparing a high-solid low-viscosity ship hull paint as claimed in claim 1, wherein: in the step S2, the dispersant is any one of a BYK dispersant W966, a BYK dispersant 108, a BYK dispersant 164, a BYK dispersant 170, a BYK dispersant 2150 and a BYK dispersant 9076.

4. The method for preparing a high-solid low-viscosity ship hull paint according to claim 1, wherein the method comprises the following steps: in step S2, the leveling agent is any one of a basf leveling agent 3522, a basf leveling agent 3580, a basf leveling agent 3650, a basf leveling agent 3886, and a basf leveling agent 7411.

5. The method for preparing the high-solid low-viscosity ship hull paint according to claim 1, wherein the modified anti-settling agent is prepared by the following steps in parts by weight:

m1, carrying out ultrasonic dispersion on 0.1-0.2 part of graphene oxide, 60-75 parts of absolute ethyl alcohol and 20-25 parts of water to obtain a graphene oxide suspension; adding 0.75-1 part of aminopropyltriethoxysilane into the graphene oxide suspension, heating and carrying out hydrolysis reaction; after the hydrolysis reaction is finished, centrifugally separating the suspension to obtain a solid crude product, and washing, washing and drying the crude product with water and alcohol to obtain a black solid product for later use;

m2, taking 0.1-0.2 part of the black solid product to disperse in 2-5 parts of N, N-dimethylformamide to obtain a reaction suspension; adding 0.1-0.15 part of 4-dimethylamino pyridine, 0.05-0.1 part of triethylamine and 1.5-3 parts of 2-bromo-2-methylpropanoyl bromide into the reaction suspension, and carrying out esterification reaction under an anaerobic condition; after the esterification reaction is finished, centrifugally separating the suspension to obtain a solid crude product, and washing, washing and drying the crude product with water and alcohol to obtain modified graphene oxide for later use;

m4, mixing 0.5-1 part of the modified graphene oxide, 3.5-8 parts of the condensation product and 75-100 parts of N, N-dimethylformamide under an anaerobic condition, and then adding 0.0001-0.0002 part of pentamethyl diethylenetriamine and 0.1-0.225 part of copper bromide for reaction; and after the reaction is finished, centrifuging to collect a solid product, washing the product with alcohol, and drying to obtain the modified anti-settling agent.

6. The method for preparing a high-solid low-viscosity ship hull paint according to claim 5, wherein the method comprises the following steps: the temperature of the hydrolysis reaction in the step M1 is 75-90 ℃, and the reaction time is 6-12 h.

7. The method for preparing a high-solid low-viscosity ship hull paint according to claim 5, wherein the method comprises the following steps: the reaction temperature of the esterification reaction in the step M2 is 65-80 ℃, and the reaction time is 6-18 h.

8. The method for preparing a high-solid low-viscosity ship hull paint as claimed in claim 5, wherein: the condensation reaction in the step M3 is carried out at the temperature of 0-25 ℃ for 0.5-2 h.

9. The method for preparing a high-solid low-viscosity ship hull paint as claimed in claim 5, wherein: the reaction temperature in the step M4 is 75-85 ℃, and the reaction time is 12-24 h.

10. A high-solid low-viscosity ship hull paint is characterized in that: prepared using the method of any one of claims 1 to 9.