CN118085692A - Two-component main chain degradation, side chain hydrolysis type marine antifouling coating and preparation method thereof - Google Patents

Abstract

The invention relates to a double-component main chain degradation side chain hydrolysis type marine antifouling paint and a preparation method thereof, and relates to the technical field of marine antifouling paint, wherein the double-component main chain degradation side chain hydrolysis type marine antifouling paint comprises a component A and a component B, and the component A comprises the following components in parts by weight: 30-60 parts of main chain degradation and side chain hydrolysis type marine antifouling resin, 0-2 parts of silane coupling agent, 0-30 parts of cuprous oxide, 0-20 parts of organic antifouling agent, 2-40 parts of pigment and filler, 0-1 part of thixotropic agent, 0-3 parts of anti-sagging agent and 0-5 parts of solvent; the component B is a curing agent containing isocyanate groups. The antifouling resin prepared by the invention has excellent main chain degradation and side chain hydrolysis performance, and can continuously release acid substances averted by marine microorganisms in the use process, and even in a static state, the surface of the coating can be gradually updated through main chain degradation, so that the antifouling effect is well exerted.

Description

Two-component main chain degradation, side chain hydrolysis type marine antifouling coating and preparation method thereof

Technical Field

The invention relates to the technical field of marine antifouling materials, in particular to a two-component main chain degradation and side chain hydrolysis type marine antifouling coating and a preparation method thereof.

Background technique

Marine biofouling, also known as marine biofouling, refers to the phenomenon that marine animals, plants and microorganisms attach to equipment running in the ocean, which brings great harm to the modern marine economy. Once marine organisms attach or grow on the surface of a ship, it will increase the friction resistance of the ship, reduce the speed, increase fuel consumption, and damage the coating, accelerate steel corrosion, seriously affect the service life of the ship, increase the frequency and cost of ship maintenance, affect normal operations, and cause huge economic losses.

According to foreign statistics and analysis, marine biofouling can increase ship fuel consumption by more than 40%, with a global total of more than 7 million tons of fuel consumed each year, causing direct economic losses of nearly 10 billion US dollars. Therefore, if the problem of marine fouling of ships is not effectively solved, it will seriously affect the implementation of national strategies and restrict the development of the marine economy. At present, China uses a large amount of marine antifouling coatings every year, most of which are monopolized by giants such as Jotun, Kansai, Hempel, China Coatings International, Akzo Nobel, and Nippon Paint Japan; especially in the field of high-tech, high-value-added high-end antifouling coatings, which are even more unmatched.

Silicone-based fouling-release coatings and polyacrylate self-polishing coatings are currently the best and most widely used marine antifouling coatings. However, their fouling-release performance depends on high water flow scouring, and the static antifouling effect is not ideal.

Patent CN112961594A discloses a hydrolysis controllable marine antifouling coating and its preparation method, the coating comprises component A and component B. Component A comprises 10-30% hydrolysis controllable resin, 0-30% other resins, 0-40% cuprous oxide, 0-10% copper pyrithione, 2-40% pigment and filler, 0.1-2% leveling agent, 0-3% thickener, 0-10% chain extender, and 10-40% solvent. Component B is a curing agent. In this scheme, the hydrolysis controllable resin is polyglycolic acid copolymer polyol. In this patent, the hydrolysis controllable resin is polyglycolic acid copolymer polyol, and its hydrolysis controllability is poor.

Patent CN114716654A discloses a self-polishing antifouling resin with main chain degradation performance and its preparation method. The raw materials for preparing the resin include the following components, calculated by mass: 1 to 60 parts of citric acid monomer; 1 to 80 parts of polyglycolic acid polyol; 1 to 80 parts of polyester or polyether polyol; 20 to 80 parts of solvent; 1 to 30 parts of zinc-containing monomer; 1 to 10 parts of monobasic acid. The antifouling resin prepared by this application scheme has excellent main chain degradation and side chain hydrolysis performance. During use, it can also continuously release citric acid substances that are disliked by marine microorganisms to form a dynamic surface with fouling resistance. Even in a static state, the coating surface can be gradually renewed through main chain degradation, thereby playing a good antifouling role. In this patent, polyglycolic acid polyol, polyester or polyether polyol is used as the main monomer, and its degradation performance also needs to be further improved.

Summary of the invention

In view of the current situation that the degradation performance of marine antifouling coatings in the prior art is poor, the present invention provides a two-component main chain degradation and side chain hydrolysis type marine antifouling coating and a preparation method thereof.

The antifouling coating of the present invention has excellent main chain degradation and side chain hydrolysis performance, and can show good antifouling effect under both dynamic and static conditions; at the same time, the operation method of the present invention is simple, the cost is low, it is suitable for industrial production, and has broad application prospects.

The purpose of the present invention can be achieved by the following technical solutions:

The present invention provides a two-component main chain degradation and side chain hydrolysis type marine antifouling coating, comprising component A and component B.

Component A contains the following components:

Wherein component B is a curing agent containing an isocyanate group;

The main chain degradation and side chain hydrolysis type marine antifouling resin has a solid content of 45% to 50% and is prepared from the following materials:

In one embodiment of the present invention, the structural formula of the citric acid monomer is as follows:

In one embodiment of the present invention, the aliphatic polyester polyol can be prepared by the following steps:

a) Under nitrogen protection, polyacid, polyol, caprolactone and catalyst are subjected to esterification and polycondensation reaction at 140-230°C, the top temperature of the fractionation tower is controlled between 100-105°C, and most of the by-product water generated is distilled off at normal pressure;

b) evacuating the chamber and gradually increasing the vacuum degree to remove trace amounts of water and excess polyol compounds under reduced pressure until the acid value of the synthesized product is lower than 5 mgKOH/g to obtain aliphatic polyester polyols; the reaction time is 4 to 12 hours.

Preferably, the aliphatic polyester polyol reaction equation is as follows:

Wherein _R1 and _R2 represent an alkyl group having 2 or more carbon atoms, and m and n are integers.

In fact, a large number of seawater degradation experiments have been conducted for common biodegradable materials. Taking common PLA as an example, under industrial composting conditions (temperature 58±2℃, humidity 98% and certain microorganisms), PLA strips lose 70% weight in about 50 days and can be completely degraded within 3 to 6 months. However, no matter whether the PLA strips are placed in fresh water or in the ocean, after one year of immersion, no obvious weight loss is observed in the PLA strips, and the GPC test shows that there is no significant change in molecular weight. Although other biodegradable materials such as PBAT and PBS degrade faster than PLA in seawater, their weight loss rate is only about 2% after one year of immersion, and the degradation is very slow. However, by copolymerization, the molecular weight and crystallinity of aliphatic polyesters can be reduced, which can greatly improve the degradation performance of aliphatic polyesters in the ocean.

Furthermore, compared with compost biodegradable materials such as PLA, PBAT and PBS that are almost not degradable in the ocean, the polycaprolactone structure can be slowly degraded in seawater; at the same time, the polycaprolactone structure has good flexibility. The present invention can be used to adjust the flexibility of the antifouling resin by adding an appropriate amount of polycaprolactone structure, so that the prepared marine antifouling coating has good adhesion.

In one embodiment of the present invention, the aliphatic polyester polyol structure is

For ease of expression, the following may be referred to as

HO——R——OH

In one embodiment of the present invention, in the method for preparing aliphatic polyester polyols, the polyacid compound is one or more of oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid and sebacic acid.

In one embodiment of the present invention, in the preparation method of aliphatic polyester polyol, the polyol compound is one or more of ethylene glycol, propylene glycol, butylene glycol, pentylene glycol, neopentyl glycol, hexylene glycol, isohexylene glycol, polyethylene glycol, polypropylene glycol, trimethylolpropane and pentaerythritol.

In one embodiment of the present invention, in the method for preparing aliphatic polyester polyol, the molar ratio of the polyol to the polyacid is (0.5-60):1, and the molecular weight of the aliphatic polyester polyol is 300-3000;

More preferably, in the method for preparing aliphatic polyester polyol, the molar ratio of the polyol to the polyacid is (1-30):1, and the molecular weight of the aliphatic polyester polyol is 500-2000.

In one embodiment of the present invention, in the preparation method of aliphatic polyester polyol, the catalyst includes one or more of stannous octoate, stannous chloride, tetrabutyl titanate, zinc acetate, antimony acetate, antimony trioxide and ethylene glycol antimony, etc.; the amount used is 0.01 to 2 wt% of the mass of all monomers.

Preferably, in the raw materials for preparing the main chain degradable and side chain hydrolyzable marine antifouling resin, the solvent is one or more of methyl acetate, ethyl acetate, butyl acetate, isopropanol, n-butanol, toluene, xylene, methyl ethyl ketone, cyclohexanone and methyl isobutyl ketone.

In one embodiment of the present invention, the zinc-containing monomer is one or more of zinc oxide, zinc hydroxide, zinc carbonate, zinc acetate and zinc chloride.

In one embodiment of the present invention, the monoacid includes one or more of formic acid, acetic acid, propionic acid, acrylic acid, methacrylic acid, glycolic acid, lactic acid and lauric acid.

Preferably, the main chain degradable and side chain hydrolyzable marine antifouling resin can be prepared by the following steps:

a) Under nitrogen protection, citric acid, aliphatic polyester polyol and a catalyst are subjected to esterification and polycondensation reaction at a certain ratio between 140 and 230° C., the top temperature of the fractionation tower is controlled between 100 and 105° C., and most of the by-product water generated is distilled off at normal pressure;

b) evacuating the mixture and gradually increasing the vacuum degree, and continuing the reaction for 80 to 150 minutes at a pressure of less than 100 Pa, and adding a solvent after cooling to obtain a main chain degradation and side chain hydrolysis type marine antifouling resin prepolymer solution;

c) Adding an appropriate amount of zinc-containing monomer to a main chain degradable and side chain hydrolyzable marine antifouling resin prepolymer solution, reacting at 30-100° C. for 0.5-2 hours, finally adding a monobasic acid, continuing the reaction for 0.5-2 hours to obtain a transparent resin solution, then passing nitrogen to continue the reaction and evaporate excess water; obtaining a main chain degradable and side chain hydrolyzable marine antifouling resin.

The structure of the main chain degradation and side chain hydrolysis type marine antifouling resin is as follows:

Here, R' represents an alkyl group, an alkoxy group, a vinyl group, etc. having a carbon number of 1 or more, and a, b, and c are integers.

The main chain of the main chain degradation and side chain hydrolysis type marine antifouling resin is based on the degradation performance of the aliphatic polyester polyol structure in seawater, thereby effectively coordinating the degradability of the coating; the antifouling coating prepared by the invention has excellent main chain degradation and side chain hydrolysis performance, and during use, it can also continuously release acid substances that are disliked by marine microorganisms to form a dynamic surface; under dynamic and static conditions, the coating surface can be gradually renewed through main chain degradation, showing a good antifouling effect.

In one embodiment of the present invention, in the preparation process of the main chain degradation and side chain hydrolysis type marine antifouling resin, the catalyst in step a) includes one or more of stannous octoate, stannous chloride, tetrabutyl titanate, zinc acetate, antimony acetate, antimony trioxide and ethylene glycol antimony, etc.; the amount used is 0.01 to 2 wt% of the mass of all monomers.

In one embodiment of the present invention, in the preparation process of the main chain degradation and side chain hydrolysis type marine antifouling resin, the molar ratio of the aliphatic polyester polyol to citric acid is 0.8 to 1.5:1; the molar ratio of the zinc-containing monomer to citric acid is 0.5 to 1.5:1; the molar ratio of the zinc-containing monomer to the monobasic acid is 1 to 10:1;

More preferably, in the preparation process of the main chain degradable and side chain hydrolyzable marine antifouling resin, the molar ratio of the aliphatic polyester polyol to citric acid is 0.9-1.1:1; the molar ratio of the zinc-containing monomer to citric acid is 0.8-1:1; and the molar ratio of the zinc-containing monomer to the monobasic acid is 1-1.5:1.

In fact, citric acid is a tricarboxylic acid compound, but due to the steric effect, the two terminal carboxyl groups will preferentially participate in the reaction. Controlling the molar ratio of aliphatic polyester polyols to citric acid can ensure that the main chain of the antifouling resin with controllable degradation rate is a linear structure, reducing body cross-linking;

Furthermore, the monoacid can consume the unreacted zinc monomer to form a zinc carboxylate structure, which can undergo ion exchange with sodium ions in seawater, thereby making the coating have side chain hydrolysis properties.

In one embodiment of the present invention, the silane coupling agent is an aminosilane coupling agent, specifically including one or more of γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane and N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane.

In one embodiment of the present invention, the organic antifouling agent includes one or more of copper pyrithione, zinc pyrithione, mancozeb, (4,5-dichloro-N-octyl-4-isothiazolin-3-one) isothiazolinone derivative (DCOIT) and bromopyrrolecarbonitrile.

In one embodiment of the present invention, the pigment filler includes one or more of zinc oxide, talc, barium sulfate, diatomaceous earth, mica powder, titanium dioxide, and red iron oxide.

Pigments and fillers are important auxiliary materials for the preparation of marine antifouling coatings. They can give the coatings different colors and glossiness, and can effectively improve the physical properties of antifouling coatings and reduce the cost of antifouling coatings.

In one embodiment of the present invention, the thixotropic agent includes one or more of organic bentonite, fumed silica, and the like.

Adding thixotropic agent can increase the viscosity of marine antifouling coatings, reduce the stratification phenomenon during the storage of coatings, and improve the storage stability of coatings.

In one embodiment of the present invention, the anti-sagging agent includes one or more of polyamide wax, vegetable oil acid, and polyurea.

In one embodiment of the present invention, the curing agent is one or more of an adduct of toluene diisocyanate and trimethylolpropane (TDI-TMP), hexamethylene diisocyanate trimer (HDI trimer), isophorone diisocyanate (IPDI), toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), hexamethylene diisocyanate (HDI) and toluene diisocyanate dimer (TDI dimer); the mass ratio of component A to component B is 1 to 100:1.

More preferably, a two-component main chain degradation, side chain hydrolysis type marine antifouling coating, the curing agent is one or more of an adduct of toluene diisocyanate and trimethylolpropane (TDI-TMP), toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), and toluene diisocyanate dimer (TDI dimer); the mass ratio of component A to component B is 10 to 50:1.

Adding an appropriate amount of curing agent can further cross-link with the hydroxyl groups in the main chain degradation and side chain hydrolysis type antifouling resin and the amino groups in the aminosilane coupling agent, thereby increasing the adhesion and hardness of the coating and improving the physical properties of the coating.

The present invention also provides a method for preparing a two-component main chain degradation and side chain hydrolysis type marine antifouling coating, comprising the following steps:

(1) According to the ratio, firstly, the main chain degradation and side chain hydrolysis type antifouling resin solution is placed in a disperser, and at a speed of 500 to 1000 r/min, a silane coupling agent and a thixotropic agent are added, and stirring is continued for 10 to 30 minutes;

(2) Add pigments, fillers and antifouling agents in the order from liquid to powder and from small to large specific gravity, and continue to disperse at a speed of 500 to 3000 r/min for 30 to 60 minutes until the fineness of the coating is less than 80 μm;

(3) replenishing the solvent according to the viscosity, adding the anti-sagging agent, continuing to stir at a speed of 500 to 3000 r/min for 20 min, filtering and packaging, and obtaining the main chain degradation and side chain hydrolysis type antifouling coating component A;

(4) Mix component A and component B directly before use.

Compared with the current acrylic ester Wuxi self-polishing resin, which generally only contains hydrolyzable side groups, its surface renewal depends on the scouring of strong water flow, and the static antifouling effect is not ideal; the antifouling resin prepared by the present invention has excellent main chain degradation and side chain hydrolysis performance, and during use, it can also continuously release acid substances that marine microorganisms hate. Even in a static state, the coating surface can be gradually renewed by main chain degradation, thereby playing a good antifouling role. The present invention has a simple operation method, low cost, can be applied to a variety of sea areas, and has a wide range of application prospects.

Compared with the prior art, the present invention has the following beneficial effects:

(1) Main chain degradation and controllable side chain hydrolysis: The present invention uses aliphatic polyester polyols with adjustable degradation rate in seawater as the main monomer, and is prepared by adjusting the crystallinity and caprolactone content of the aliphatic polyester polyols, and combining citric acid monomers and zinc-containing monomers; according to different situations, we can prepare a series of self-polishing antifouling resins with different molecular weights and molecular structures to adapt to different usage occasions; these resins have both main chain degradation and side chain hydrolysis effects, and show good antifouling effects under both dynamic and static conditions.

(2) The main chain degradable and side chain hydrolyzable antifouling coating developed by us will continuously release acidic substances with antibacterial effects during the degradation process, so that the seawater on the coating surface forms a certain pH difference with normal seawater, making it difficult for marine fouling organisms to attach to its surface.

(3) The main chain degradation and side chain hydrolysis antifouling coating developed has introduced citric acid monomer, aminosilane coupling agent and isocyanate curing agent, which makes the coating have high strength and adhesion and excellent physical properties.

(4) The main chain degradable and side chain hydrolyzable antifouling resins developed can be biodegraded in the ocean, reducing the generation of marine microplastics. They are environmentally friendly antifouling resins.

(5) The main chain degradable and side chain hydrolyzable antifouling coatings developed have abundant raw material sources, simple production processes, and affordable prices, making them suitable for industrial production.

In summary, the main chain degradation and side chain hydrolysis type marine antifouling coating provided by the present invention has both main chain degradation and side chain hydrolysis effects, and exhibits good antifouling effects under dynamic and static conditions. More importantly, the operation method of the present invention is simple, low-cost, and suitable for industrial production.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a shallow sea immersion test result, wherein numbers 1, 2, 3, 4, 5, 6, 7, and 8 are coatings of Example 1, Example 2, Example 3, Example 4, Example 5, Example 6, Comparative Example 1, and Comparative Example 2, respectively.

Detailed ways

In order to enable technicians in this technical field to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the embodiments of the present invention. However, the present invention can be implemented in different forms and is not limited to the embodiments described in the text. All other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

In the following embodiments:

As a preferred embodiment, the main chain degradable and side chain hydrolyzable antifouling resin is used as the film-forming resin, and the main chain degradable and side chain hydrolyzable marine antifouling coating component A can be prepared by the following method:

(1) According to the ratio, the main chain degradation and side chain hydrolysis type antifouling resin solution is first placed in a disperser, and auxiliary agents such as silane coupling agent and thixotropic agent are added at a speed of 500 to 1000 r/min, and stirring is continued for 10 to 30 minutes.

(2) Add pigments, fillers and antifouling agents in the order from liquid to powder and from small to large specific gravity, and continue to disperse at a speed of 500-3000 r/min for 30-60 minutes until the paint fineness is below 80 μm.

(3) according to the viscosity, the solvent is supplemented and the anti-sagging agent is added, and the stirring is continued at a speed of 500-3000 r/min for 20 min, and the mixture is filtered and packaged to obtain the main chain degradation and side chain hydrolysis type antifouling coating component A.

Component B is a commercially available product and can be used directly by mixing during coating.

The acid value determination method is as follows: weigh 1-3g of polymer polyol, place it in a three-necked flask, add 20-30mL of a toluene-ethanol (2:1) mixed solution, shake the conical flask to completely dissolve the sample, heat it when necessary, drop 1% phenolphthalein indicator, titrate with 0.1mol/L standard KOH solution until it turns slightly red, and the end point is that it does not fade within 30s, and at the same time, a blank test is performed according to the same method.

Where:

_Vtest ——the volume of standard solution of KOH consumed in the test, mL;

_Vblank ——the volume of the standard solution of KOH consumed in the blank, mL;

C——molar concentration of KOH standard solution, mol/L;

W——sample mass, g;

56.10 – The molar mass of potassium hydroxide, g/mol.

The present invention has no special restrictions on the raw materials used above, and they can be commonly available on the market.

To further illustrate the present invention, the present invention will be further described below in conjunction with specific embodiments.

Embodiment 1:

Aliphatic polyester polyol preparation:

Under nitrogen protection, 59 g (0.5 mol) of succinic acid, 63.6 g (0.6 mol) of diethylene glycol, 34.2 g (0.3 mol) of caprolactone and 0.3 g of zinc acetate were added to the reactor, the oil bath was heated to 175°C, the temperature at the top of the distillation tower was maintained at 100-105°C, and the reaction was carried out for 4 hours; then, the vacuum was evacuated and the vacuum degree was gradually increased, and trace water and excess diethylene glycol were removed under reduced pressure to obtain 130 g of transparent viscous aliphatic polyester polyol.

Preparation of antifouling resin with main chain degradation and side chain hydrolysis performance

Under nitrogen protection, 27.3 g (0.13 mol) of citric acid monohydrate, 130 g of the above-mentioned aliphatic polyester polyol and 0.3 g of zinc acetate were added to the reactor, the oil bath was heated to 190° C., the temperature of the top of the fractionation tower was maintained at 100-105° C., and the reaction was carried out for 2 hours; then, the vacuum was evacuated, and the vacuum degree was gradually increased, and trace water and excess alcohol were removed under reduced pressure to obtain 124 g of product, and then 90 g of butyl acetate and 60 g of methyl isobutyl ketone solvent were added for dissolution to obtain a main chain degradation and side chain hydrolysis performance antifouling resin prepolymer solution;

8.1 g (0.1 mol) of zinc oxide was added to the above solution, and the reaction was carried out at 80°C for 30 min. Finally, 5.8 g (0.08 mol) of acrylic acid was added and the reaction was continued for 30 min to obtain a light yellow transparent resin solution. Subsequently, nitrogen was passed through to continue the reaction and excess water was evaporated to obtain a main chain degradation and side chain hydrolysis type antifouling resin solution with a solid content of 46%.

Prepare the marine antifouling coating component A (containing cuprous oxide) according to the following weight ratio:

The invention comprises: 42g of the above-mentioned main chain degradation and side chain hydrolysis antifouling resin solution, 1g of silane coupling agent γ-aminopropyltriethoxysilane, 20g of cuprous oxide, 3g of organic antifouling agent copper pyrithione, 29g of color fillers (including 5g of zinc oxide, 10g of talc, 10g of barium sulfate and 4g of red iron oxide), 1g of organic bentonite, 1g of polyamide wax anti-sagging agent and 3g of xylene solvent.

The curing agent of component B is an addition product of toluene diisocyanate and trimethylolpropane (TDI-TMP), and the amount used is 6% of component A.

Embodiment 2:

The main chain degradation and side chain hydrolysis type antifouling resin solution is the same as that in Example 1;

Prepare the marine antifouling coating component A (excluding cuprous oxide) according to the following weight ratio:

The invention comprises: 42g of the above-mentioned main chain degradation and side chain hydrolysis antifouling resin solution, 1g of silane coupling agent γ-aminopropyltriethoxysilane, 10g of organic antifouling agent (including 3g of bromopyrrolecarbonitrile, 3-pyridinethione copper and 4g of DCOIT), 40g of color filler (including 5g of zinc oxide, 15g of talc, 15g of barium sulfate and 5g of red iron oxide), 1g of organic bentonite, 1g of polyamide wax anti-sagging agent and 5g of xylene solvent.

The curing agent of component B is toluene diisocyanate (TDI), and the amount used is 2% of component A.

Embodiment 3:

Aliphatic polyester polyol preparation:

Under nitrogen protection, 41.6 g (0.4 mol) of malonic acid, 23.6 g (0.2 mol) of succinic acid, 72.8 g (0.7 mol) of neopentyl glycol, 45.6 g (0.4 mol) of caprolactone and 0.2 g of stannous octoate were added to the reactor, the oil bath was heated to 185°C, the top temperature of the distillation tower was maintained at 100-105°C, and the reaction was carried out for 3 hours; then, the vacuum was evacuated and the vacuum degree was gradually increased, and trace water and excess neopentyl glycol were removed under reduced pressure to obtain 145 g of viscous aliphatic polyester polyol.

Preparation of antifouling resin with main chain degradation and side chain hydrolysis performance

Under nitrogen protection, 31.5 g (0.15 mol) of citric acid monohydrate, 145 g of the above-mentioned aliphatic polyester polyol and 0.3 g of stannous octoate were added to the reactor, the oil bath was heated to 195° C., the temperature of the top of the fractionation tower was maintained at 100-105° C., and the reaction was carried out for 2 hours; then, the vacuum was evacuated, and the vacuum degree was gradually increased, and trace water and excess alcohol were removed under reduced pressure to obtain 155 g of the product, and then 180 g of butyl acetate solvent was added for dissolution to obtain a main chain degradation and side chain hydrolysis performance antifouling resin prepolymer solution;

12 g (0.12 mol) of zinc hydroxide was added to the above solution, and the reaction was carried out at 80° C. for 30 min. Finally, 6 g (0.1 mol) of glacial acetic acid was added and the reaction was continued for 30 min to obtain a light yellow transparent resin solution. Subsequently, nitrogen was passed through to continue the reaction and excess water was evaporated to obtain a main chain degradation and side chain hydrolysis type antifouling resin solution with a solid content of 48%.

Prepare the marine antifouling coating component A (containing cuprous oxide) according to the following weight ratio:

The invention comprises: 42g of the above-mentioned main chain degradation and side chain hydrolysis antifouling resin solution, 1g of silane coupling agent γ-aminopropyltriethoxysilane, 20g of cuprous oxide, 3g of organic antifouling agent copper pyrithione, 29g of color fillers (including 5g of zinc oxide, 10g of talc, 10g of barium sulfate and 4g of red iron oxide), 1g of organic bentonite, 1g of polyamide wax anti-sagging agent and 3g of xylene solvent.

The curing agent of component B is an addition product of toluene diisocyanate and trimethylolpropane (TDI-TMP), and the amount used is 8% of component A.

Embodiment 4:

The main chain degradation and side chain hydrolysis type antifouling resin solution is the same as that in Example 3;

Prepare the marine antifouling coating component A (excluding cuprous oxide) according to the following weight ratio:

The invention comprises: 42g of the above-mentioned main chain degradation and side chain hydrolysis antifouling resin solution, 1g of silane coupling agent γ-aminopropyltriethoxysilane, 10g of organic antifouling agent (including 3g of bromopyrrolecarbonitrile, 3-pyridinethione copper and 4g of DCOIT), 40g of color filler (including 5g of zinc oxide, 15g of talc, 15g of barium sulfate and 5g of red iron oxide), 1g of organic bentonite, 1g of polyamide wax anti-sagging agent and 5g of xylene solvent.

The curing agent of component B is toluene diisocyanate (TDI), and the amount used is 3% of component A.

Embodiment 5:

Aliphatic polyester polyol preparation:

Under nitrogen protection, 47.2g (0.4mol) of succinic acid, 58.4g (0.4mol) of adipic acid, 67g (0.88mol) of 1,2-propylene glycol and 22.8g (0.2mol) of caprolactone were added to the reactor, the oil bath was heated to 140°C, and after removing the water, 0.2g of tetrabutyl titanate catalyst was added. Subsequently, the oil bath was heated to 200°C, and the top temperature of the distillation tower was maintained at 100-105°C, and the reaction was carried out for 5h; finally, the vacuum was evacuated and the vacuum degree was gradually increased, and trace water and excess 1,2-propylene glycol were removed under reduced pressure to obtain 155g of viscous aliphatic polyester polyol.

Preparation of antifouling resin with main chain degradation and side chain hydrolysis performance

Under nitrogen protection, 25.2g (0.12mol) of citric acid monohydrate, 155g of the above-mentioned aliphatic polyester polyol and 0.3g of tetrabutyl titanate were added to the reactor, the oil bath was heated to 200°C, the temperature of the top of the fractionation tower was maintained at 100-105°C, and the reaction was carried out for 2h; then, the vacuum was evacuated, and the vacuum degree was gradually increased, and trace water and excess alcohol were removed under reduced pressure to obtain 164g of product, and then 100g of butyl acetate and 80g of ethyl acetate solvent were added for dissolution to obtain a main chain degradation and side chain hydrolysis performance antifouling resin prepolymer solution;

7.3 g (0.09 mol) of zinc oxide was added to the above solution, and the reaction was carried out at 80°C for 30 min. Finally, 12 g (0.06 mol) of lauric acid was added and the reaction was continued for 30 min to obtain a light yellow transparent resin solution. Subsequently, nitrogen was passed through to continue the reaction and excess water was evaporated to obtain a main chain degradation and side chain hydrolysis type antifouling resin solution with a solid content of 48%.

Prepare the marine antifouling coating component A (containing cuprous oxide) according to the following weight ratio:

The invention comprises: 42g of the above-mentioned main chain degradation and side chain hydrolysis antifouling resin solution, 1g of silane coupling agent γ-aminopropyltriethoxysilane, 20g of cuprous oxide, 3g of organic antifouling agent copper pyrithione, 29g of color fillers (including 5g of zinc oxide, 10g of talc, 10g of barium sulfate and 4g of red iron oxide), 1g of organic bentonite, 1g of polyamide wax anti-sagging agent and 3g of xylene solvent.

The curing agent of component B is an addition product of toluene diisocyanate and trimethylolpropane (TDI-TMP), and the amount used is 8% of component A.

Embodiment 6:

The main chain degradation and side chain hydrolysis type antifouling resin solution is the same as that in Example 5;

Prepare the marine antifouling coating component A (excluding cuprous oxide) according to the following weight ratio:

The invention comprises: 42g of the above-mentioned main chain degradation and side chain hydrolysis antifouling resin solution, 1g of silane coupling agent γ-aminopropyltriethoxysilane, 10g of organic antifouling agent (including 3g of bromopyrrolecarbonitrile, 3-pyridinethione copper and 4g of DCOIT), 40g of color filler (including 5g of zinc oxide, 15g of talc, 15g of barium sulfate and 5g of red iron oxide), 1g of organic bentonite, 1g of polyamide wax anti-sagging agent and 5g of xylene solvent.

The curing agent of component B is toluene diisocyanate (TDI), and the amount used is 3% of component A.

Comparative Example 1:

Preparation of polylactic acid polyol:

Under nitrogen protection, 102g (1mol) of lactic acid with a mass concentration of 88%, 6g (0.08mol) of 1,3-propylene glycol and 0.2g of stannous octoate were added to the reactor, the oil bath was heated to 185°C, and the temperature at the top of the distillation tower was maintained at 100-105°C for 5h; then, the vacuum was evacuated and the vacuum degree was gradually increased, and trace water and excess 1,3-propylene glycol were removed under reduced pressure to obtain 66g of waxy polylactic acid polyol.

Preparation of antifouling resin with main chain degradation and side chain hydrolysis performance

Under nitrogen protection, 25.2g (0.12mol) of citric acid monohydrate, 66g of the above-mentioned polylactic acid polyol and 0.3g of stannous octoate were added to the reactor, the oil bath was heated to 200°C, the temperature of the top of the fractionation tower was maintained at 100-105°C, and the reaction was carried out for 3h; then, the vacuum was evacuated, and the vacuum degree was gradually increased, and trace water and excess alcohol were removed under reduced pressure to obtain 73g of product, and then 70g of butyl acetate and 15g of ethyl acetate solvent were added for dissolution to obtain a main chain degradation and side chain hydrolysis performance antifouling resin prepolymer solution;

7.3 g (0.09 mol) of zinc oxide was added to the above solution, and the reaction was carried out at 80°C for 30 min. Finally, 4.2 g (0.07 mol) of glacial acetic acid was added and the reaction was continued for 30 min to obtain a light yellow transparent resin solution. Subsequently, nitrogen was passed through to continue the reaction and excess water was evaporated to obtain a main chain degradation and side chain hydrolysis type antifouling resin solution with a solid content of 48%.

Prepare the marine antifouling coating component A (containing cuprous oxide) according to the following weight ratio:

The invention comprises: 42g of the above-mentioned main chain degradation and side chain hydrolysis antifouling resin solution, 1g of silane coupling agent γ-aminopropyltriethoxysilane, 20g of cuprous oxide, 3g of organic antifouling agent copper pyrithione, 29g of color fillers (including 5g of zinc oxide, 10g of talc, 10g of barium sulfate and 4g of red iron oxide), 1g of organic bentonite, 1g of polyamide wax anti-sagging agent and 3g of xylene solvent.

The curing agent of component B is an addition product of toluene diisocyanate and trimethylolpropane (TDI-TMP), and the amount used is 8% of component A.

Comparative Example 2:

The main chain degradation and side chain hydrolysis type antifouling resin solution is the same as that of comparative example 1;

Prepare the marine antifouling coating component A (excluding cuprous oxide) according to the following weight ratio:

The invention comprises: 42g of the above-mentioned main chain degradation and side chain hydrolysis antifouling resin solution, 1g of silane coupling agent γ-aminopropyltriethoxysilane, 10g of organic antifouling agent (including 3g of bromopyrrolecarbonitrile, 3-pyridinethione copper and 4g of DCOIT), 40g of color filler (including 5g of zinc oxide, 15g of talc, 15g of barium sulfate and 5g of red iron oxide), 1g of organic bentonite, 1g of polyamide wax anti-sagging agent and 5g of xylene solvent.

The curing agent of component B is toluene diisocyanate (TDI), and the amount used is 3% of component A.

Long-term firm adhesion to the surface of the substrate is a prerequisite for the marine antifouling coating to exert its antifouling effect, so the coating adhesion strength is one of the important indicators for testing the quality of marine antifouling coatings. The coating adhesion strength is measured by the tensile method.

Using the mark iron sheet coated with epoxy zinc-rich primer as the substrate, the eight marine antifouling coatings prepared in Examples 1 to 6 and Comparative Examples 1 to 2 were tested for adhesion strength according to ASTM D 4541 standard. As shown in Table 1, the adhesion strength of the antifouling coatings prepared in Examples 1 to 6 and Comparative Examples 1 to 2 exceeded 2 MPa, which fully met the use requirements of marine antifouling coatings.

Table 1 Adhesion strength of antifouling coatings obtained in Examples 1 to 6 and Comparative Examples 1 to 2

The 8 kinds of marine antifouling coatings prepared in Examples 1 to 6 and Comparative Examples 1 to 2 were subjected to shallow sea immersion tests in accordance with the national standard GB/T5370-2007 "Shallow Sea Immersion Test Method for Antifouling Paint Samples". The test site was Luomen Sea Area, Zhoushan City, where the antifouling agents and additives used in Examples 1, 3, 5 and Comparative Example 1 were the same, and the antifouling agents and additives used in Examples 2, 4, 6 and Comparative Example 2 were the same, and did not contain cuprous oxide; the test time was from July 22, 2022 to July 19, 2023, and the cycle was one year. As shown in Figure 1, after one year of shallow sea immersion experiments, the surfaces of the samples of Examples 1 to 6 were still smooth, with basically no marine organisms attached, and had good antifouling performance; while in Comparative Examples 1 to 2, since only the polylactic acid polyol structure with a slower degradation rate was added to the main chain, the coating degradation rate was slow, and the antifouling effect was not ideal. At the same time, the operation method of the present invention is simple, low cost, and suitable for industrial production.

The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims (10)

1. A two-component main chain degradation and side chain hydrolysis type marine antifouling coating, characterized in that it comprises component A and component B, Component A contains the following components: Wherein component B is a curing agent containing an isocyanate group; The main chain degradation and side chain hydrolysis type marine antifouling resin has a solid content of 45% to 50% and is prepared from the following materials: The structure of the main chain degradation and side chain hydrolysis type marine antifouling resin is as follows: Here, R' represents an alkyl group, an alkoxy group, and a vinyl group having 1 or more carbon atoms, and a, b, and c are integers. 2. A two-component main chain degradable, side chain hydrolyzable marine antifouling coating according to claim 1, characterized in that the structural formula of the citric acid monomer is as follows: 3. A two-component main chain degradation, side chain hydrolysis type marine antifouling paint according to claim 1, characterized in that the aliphatic polyester polyol structure is Wherein _R1 and _R2 represent an alkyl group having 2 or more carbon atoms, and m and n are integers. 4. A two-component main chain degradable, side chain hydrolyzable marine antifouling coating according to claim 3, characterized in that the aliphatic polyester polyol can be prepared by the following steps: a) Under nitrogen protection, polyacid, polyol, caprolactone and catalyst are subjected to esterification and polycondensation reaction at 140-230°C, the top temperature of the fractionation tower is controlled between 100-105°C, and most of the by-product water generated is distilled off at normal pressure; b) evacuating the mixture and gradually increasing the vacuum degree to remove trace amounts of water and excess polyol compounds under reduced pressure until the acid value of the synthesized product is lower than 5 mgKOH/g to obtain aliphatic polyester polyols; the reaction time is 4 to 12 hours; The polyacid compound is one or more of oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid and sebacic acid; The polyol compound is one or more of ethylene glycol, propylene glycol, butylene glycol, pentylene glycol, neopentyl glycol, hexylene glycol, isohexylene glycol, polyethylene glycol, polypropylene glycol, trimethylolpropane and pentaerythritol; The molar ratio of the polyol to the polyacid is (0.5-60):1, and the molecular weight of the aliphatic polyester polyol is 300-3000; The catalyst comprises one or more of stannous octoate, stannous chloride, tetrabutyl titanate, zinc acetate, antimony acetate, antimony trioxide and ethylene glycol antimony; and the amount used is 0.01-2wt% of the mass of all monomers. 5. A two-component main chain degradable, side chain hydrolyzable marine antifouling coating according to claim 1, characterized in that the solvent used to prepare the main chain degradable, side chain hydrolyzable marine antifouling resin is one or more of methyl acetate, ethyl acetate, butyl acetate, isopropanol, n-butanol, toluene, xylene, methyl ethyl ketone, cyclohexanone and methyl isobutyl ketone; The zinc-containing monomer is one or more of zinc oxide, zinc hydroxide, zinc carbonate, zinc acetate and zinc chloride; The monoacid includes one or more of formic acid, acetic acid, propionic acid, acrylic acid, methacrylic acid, glycolic acid, lactic acid and lauric acid. 6. A two-component main chain degradation, side chain hydrolysis type marine antifouling coating according to claim 1, characterized in that the main chain degradation, side chain hydrolysis type marine antifouling resin can be prepared by the following steps: a) Under nitrogen protection, citric acid, aliphatic polyester polyol and a catalyst are subjected to esterification and polycondensation reaction at a certain ratio between 140 and 230° C., the top temperature of the fractionation tower is controlled between 100 and 105° C., and most of the by-product water generated is distilled off at normal pressure; b) evacuating the mixture and gradually increasing the vacuum degree, and continuing the reaction for 80 to 150 minutes at a pressure of less than 100 Pa, and adding a solvent after cooling to obtain a main chain degradation and side chain hydrolysis type marine antifouling resin prepolymer solution; c) adding an appropriate amount of zinc-containing monomer to a main chain degradable and side chain hydrolyzable marine antifouling resin prepolymer solution, reacting at 30-100° C. for 0.5-2 hours, finally adding a monobasic acid, and continuing the reaction for 0.5-2 hours to obtain a transparent resin solution, then passing nitrogen to continue the reaction, and evaporating excess water; obtaining a main chain degradable and side chain hydrolyzable marine antifouling resin; The catalyst in step a) comprises one or more of stannous octoate, stannous chloride, tetrabutyl titanate, zinc acetate, antimony acetate, antimony trioxide and ethylene glycol antimony; the amount used is 0.01-2wt% of the mass of all monomers; The molar ratio of the aliphatic polyester polyol to citric acid is 0.8-1.5:1; the molar ratio of the zinc-containing monomer to citric acid is 0.5-1.5:1; and the molar ratio of the zinc-containing monomer to monoacid is 1-10:1. 7. A two-component main chain degradable, side chain hydrolyzable marine antifouling coating according to claim 1, characterized in that the silane coupling agent is an aminosilane coupling agent, specifically including one or more of γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane and N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane; The organic antifouling agent includes one or more of copper pyrithione, zinc pyrithione, mancozeb, (4,5-dichloro-N-octyl-4-isothiazoline-3-one)isothiazolinone derivatives and bromopyrrole nitrile; The pigments and fillers include one or more of zinc oxide, talc, barium sulfate, diatomaceous earth, mica powder, titanium dioxide and red iron oxide; The thixotropic agent includes one or more of organic bentonite and fumed silica; The anti-sagging agent includes one or more of polyamide wax, vegetable oil acid and polyurea. 8. A two-component main chain degradation, side chain hydrolysis type marine antifouling coating according to claim 1, characterized in that the curing agent is one or more of an adduct of toluene diisocyanate and trimethylolpropane, hexamethylene diisocyanate trimer, isophorone diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate and toluene diisocyanate dimer. 9. A two-component main chain degradable, side chain hydrolyzable marine antifouling coating according to claim 1, characterized in that the mass ratio of component A to component B is 1 to 100:1. 10. The method for preparing the two-component main chain degradable and side chain hydrolyzable marine antifouling coating according to any one of claims 1 to 9, characterized in that it comprises the following steps: (1) According to the ratio, firstly, the main chain degradation and side chain hydrolysis type antifouling resin solution is placed in a disperser, and at a speed of 500 to 1000 r/min, a silane coupling agent and a thixotropic agent are added, and stirring is continued for 10 to 30 minutes; (2) Add pigments, fillers and antifouling agents in the order from liquid to powder and from small to large specific gravity, and continue to disperse at a speed of 500 to 3000 r/min for 30 to 60 minutes until the fineness of the coating is less than 80 μm; (3) replenishing the solvent according to the viscosity, adding the anti-sagging agent, continuing to stir at a speed of 500 to 3000 r/min for 20 min, filtering and packaging, and obtaining the main chain degradation and side chain hydrolysis type antifouling coating component A; (4) Mix component A and component B directly before use.