CN111378356A - Anti-icing coating for low-temperature high-humidity environment and preparation method thereof - Google Patents

Abstract

The invention discloses an anti-icing coating for a low-temperature high-humidity environment, which comprises a component A and a component B, wherein the component A comprises the following components in percentage by mass: 45-65 wt% of polyurethane resin, 10-20 wt% of functional porous nano material, 17-25 wt% of wear-resistant filler, 10-15 wt% of solvent and 2-3 wt% of auxiliary agent; the component B is an isocyanate curing agent, and the mass ratio of the component A to the component B is (5-5.5): 1. The preparation method comprises the following steps: preparing a functional porous nano material, namely uniformly stirring the elastic polyurethane resin, the auxiliary agent, the solvent accounting for 70 percent of the total amount and the functional porous nano material at a low speed; then adding the wear-resistant filler and uniformly stirring at a high speed; grinding for 0.5-4 h after uniformly stirring, and finally adding the residual solvent to adjust the viscosity to obtain a component A; before use, the component A and the component B are mixed and stirred uniformly to obtain the anti-icing coating. The coating has good film forming property and compact structure, the surface of the coating has lower icing temperature and better hydrophobic property, and the coating has good anti-icing property in low-temperature and high-humidity environment.

Description

Anti-icing coating for low-temperature high-humidity environment and preparation method thereof

Technical Field

The invention relates to the technical field of coatings, in particular to an anti-icing coating for a low-temperature high-humidity environment and a preparation method thereof.

Background

Polar vessels are mainly used in extremely low temperature environments, which are not only low in temperature but also high in humidity, and particularly increase air humidity due to water waves and the like splashed during the operation of the vessels. Under the low-temperature and high-humidity environment, water vapor is mainly condensed on the surface of the coating to form ice crystals, and an ice layer is finally formed on the surface of the coating along with the accumulation of a large amount of ice crystals, so that the thick ice layer is covered on the superstructure of the polar ship, the weight of the ship body is increased, the energy consumption is increased, and potential safety hazards exist.

At present, the anti-icing coating researched at home and abroad can be divided into a sacrificial coating and a hydrophobic coating from the aspects of an anti-icing principle and influence on ice adhesion. The sacrificial coating mainly utilizes the fact that an anti-icing agent is released from the surface of the coating to reduce the freezing point of water, and a thin water film is formed between ice and the surface of the coating, so that the ice is not easy to adhere to the surface of the coating. The hydrophobic coating realizes the super-hydrophobic performance of the coating based on the micro-nano structure on the surface of the coating, but the micro-nano structure cannot achieve the anti-icing performance under the low-temperature high-humidity environment due to the entering of water vapor, but can increase the binding force between an ice layer and the coating and is difficult to deice, so that the sacrificial coating is mainly used for the low-temperature high-humidity environment, and the anti-icing performance is realized by combining the hydrophobic characteristic on the surface of the coating.

Foreign technology

Super-hydrophobic coatings with contact angles of over 150 ° have been developed in cold countries such as the united states, canada, russia, and the like, by means of organic-inorganic hybridization in combination with anti-icing agents. The patent No. US20181619568 'ICE PHOBIC COATINGFORMATIONSAND USE THEREOF' realizes the anti-icing performance by adopting elastomer, filler particles and low-temperature protective agent; patent No. US201815863222, "ACTIVE ANTI-ICE COATING, COATING material method" uses the release of an anti-icing agent to achieve anti-icing, but requires the use of uv curing to achieve persistence of anti-icing.

Domestic technology

The domestic research on the aspect of anti-icing coatings is mainly hydrophobic coatings, and Chinese patent with publication number CN104449317A discloses an anti-icing covering coating. Chinese patent publication No. CN109722150A discloses an anti-icing wind power blade and a method for manufacturing the same, wherein conductive filler is added to reduce the freezing point or raise the surface temperature of a substrate to effectively delay the formation of ice crystals, so as to achieve the anti-icing effect, but the coating needs anti-lightning protection and cannot be widely applied. In the prior art, a surface microstructure is formed by means of surface etching or micro-nano structure combination and the like, so that a hydrophobic coating with a lotus leaf effect is widely researched in the field of anti-icing, but the surface durability of the currently prepared coating is poor, and the currently prepared coating is not suitable for environments such as strong wind, high humidity and the like.

Disclosure of Invention

In order to solve the defects in the prior art, the invention provides an anti-icing coating for a low-temperature high-humidity environment and a preparation method thereof.

In order to achieve the purpose, the invention adopts the specific scheme that: an anti-icing coating for a low-temperature high-humidity environment comprises a component A and a component B, wherein the component A comprises the following components in percentage by mass:

45-65 wt% of polyurethane resin;

10-20 wt% of functional porous nano material;

17-25 wt% of wear-resistant filler;

10-15 wt% of a solvent;

2-3 wt% of an auxiliary agent;

the component B is an isocyanate curing agent;

the mass ratio of the component A to the component B is (5-5.5) to 1.

Further, the polyurethane resin is a hydroxyl group-containing polyurethane resin. The polyurethane resin can endow the coating with good flexibility under the low-temperature condition, solve the problem of low-temperature brittleness of the coating and ensure the application of the coating under the low-temperature condition.

Further, the preparation method of the functional porous nano material comprises the following steps: adding 100g of ethanol solution into a container, introducing nitrogen as a protective gas, dispersing 5-10 g of organic metal alkoxide and 40-45 g of low-surface-energy modifier into the ethanol solution together, performing ultrasonic dispersion uniformly, adding a porous nano material with the mass being 40-50% of that of the low-surface-energy modifier, continuing performing ultrasonic dispersion uniformly, and then placing the porous nano material in a vacuum oven at the temperature of 60 ℃ for drying to obtain the functional porous nano material.

Further, the organic metal alkoxide is any one of an ethylene glycol aluminum salt, an isopropyl alcohol aluminum salt, and a n-hexanol aluminum salt.

Further, the low surface energy modifier is any one of perfluorosilane, perfluorooctanoic acid and a perfluoroethylene propylene copolymer.

Further, the porous nano material is any one of porous nano silicon dioxide, porous nano titanium dioxide and carbon nano tubes.

Further, the wear-resistant material is any one or two of aluminum oxide, zirconium oxide, glass beads and polytetrafluoroethylene. The wear-resistant filler can improve the surface wear resistance of the coating and ensure the stability of the coating under the wear of the ice layer.

Further, the solvent is any one or more of xylene, acetone, n-butanol and ethyl acetate. The solvent mainly meets the requirements of coating production and construction.

A method for preparing an anti-icing coating for a low-temperature high-humidity environment comprises the following steps:

adding an ethanol solution into a three-neck flask, introducing nitrogen for protection, dispersing 5-10 g of organic metal alkoxide and 40-45 g of low-surface-energy modifier into the ethanol solution, uniformly dispersing by ultrasonic, adding a porous nano material with the mass being 40-50% of that of the low-surface-energy modifier, continuously dispersing uniformly by ultrasonic, and then placing the mixture in a vacuum oven at the temperature of 60 ℃ for drying to obtain a functional porous nano material;

step two, weighing the elastic polyurethane resin, the auxiliary agent, the solvent accounting for 70% of the total amount and the functional porous nano material prepared in the step one according to a formula, adding into a charging basket, and uniformly stirring at a low speed by using stirring equipment;

step three, adding the wear-resistant filler into the mixture obtained in the step two, and uniformly stirring at a high speed; uniformly stirring, grinding for 0.5-4 h until the fineness of the coating is reduced to below 40 mu m, and finally adding the residual solvent to adjust the viscosity to obtain a component A;

and step four, mixing the component A and the component B before use, and uniformly stirring to obtain the anti-icing coating.

The auxiliary agent comprises a thixotropic agent, a flatting agent, a defoaming agent and a dispersing agent. Among other things, thixotropic agents provide good sag resistance and storage stability; the leveling agent provides excellent surface smoothness and workability, the defoaming agent can eliminate bubbles generated in the production and transportation processes of the coating, and the dispersing agent can improve good dispersion compatibility between the organic resin and the inorganic filler. Wherein, the thixotropic agent is any one or more of fumed silica, organic bentonite and polyamide wax, the flatting agent is any one or more of BYK-320, Glide450 and EFKA-3777, the defoaming agent is any one or more of 6800, 6600 and BYK-066, and the dispersing agent is any one or more of BYK-110 and BYK-163.

The isocyanate curing agent can endow the coating with excellent elasticity, weather resistance and normal temperature curing property, and has important effects on high toughness, wear resistance and resistance reduction of the coating.

It should be noted that: the low-temperature high-humidity environment in the present invention means: the temperature is lower than-5 ℃, and the relative humidity of air is higher than 70%.

Has the advantages that:

1. the organic alkoxide exists stably in the coating, but when the organic alkoxide is released to the surface of the coating, the organic alkoxide is hydrolyzed when meeting water on the surface of the coating, so that small organic molecular alcohols are released, and the small organic molecular alcohols can reduce the freezing point of ice on the surface of the coating, thereby realizing the anti-icing property. Meanwhile, the addition of the low surface energy modifier enables the surface of the coating to have hydrophobicity, so that water drops and ice layers can easily slide off from the surface of the coating, and the anti-icing performance of the coating is realized. As the porous nanomaterial has the storage and release functions, the organic metal alkoxide and the low surface energy modifier are introduced into the hydrophobic coating through the storage and release of the porous nanomaterial, once the hydrophobic and low freezing point substances on the surface of the coating are consumed or damaged, the organic metal alkoxide and the low surface energy modifier stored in the porous nanomaterial can be spontaneously released and migrate to the surface of the coating and undergo hydrolysis, and the self-repairing and durability of the anti-icing performance of the coating is realized.

2. The invention has simple production process, does not need complex equipment, is convenient to construct and can be cured at normal temperature; the coating prepared by the coating has good film forming property and compact structure, the surface of the coating has lower icing temperature and better hydrophobic property, and the coating has good anti-icing property in low-temperature and high-humidity environment.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to specific embodiments, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, belong to the scope of the present invention.

It should be noted that various raw materials used in the following examples are conventional commercially available products unless otherwise specified.

An anti-icing coating for a low-temperature high-humidity environment comprises a component A and a component B, wherein the component A comprises the following components in percentage by mass:

45-65 wt% of polyurethane resin;

10-20 wt% of functional porous nano material;

17-25 wt% of wear-resistant filler;

10-15 wt% of a solvent;

2-3 wt% of an auxiliary agent;

the component B is an isocyanate curing agent;

the mass ratio of the component A to the component B is (5-5.5) to 1.

Wherein the polyurethane resin is a hydroxyl-containing polyurethane resin.

The preparation method of the functional porous nano material comprises the following steps: adding 100g of ethanol solution into a container, introducing nitrogen as a protective gas, dispersing 5-10 g of organic metal alkoxide and 40-45 g of low-surface-energy modifier into the ethanol solution together, performing ultrasonic dispersion uniformly, adding a porous nano material with the mass being 40-50% of that of the low-surface-energy modifier, continuing performing ultrasonic dispersion uniformly, and then placing the porous nano material in a vacuum oven at the temperature of 60 ℃ for drying to obtain a functional porous nano material; the organic metal alkoxide is any one of ethylene glycol aluminum salt, isopropanol aluminum salt and n-hexanol aluminum salt; the low surface energy modifier is any one of perfluorosilane, perfluorooctanoic acid and a perfluoroethylene-propylene copolymer; the porous nano material is any one of porous nano silicon dioxide, porous nano titanium dioxide and carbon nano tubes.

The wear-resistant material is any one or two of alumina, zirconia, glass beads and polytetrafluoroethylene powder.

The solvent is any one or more of dimethylbenzene, acetone, n-butanol and ethyl acetate.

A method for preparing an anti-icing coating for a low-temperature high-humidity environment comprises the following steps:

adding an ethanol solution into a three-neck flask, introducing nitrogen for protection, dispersing 5-10 g of organic metal alkoxide and 40-45 g of low-surface-energy modifier into the ethanol solution, uniformly dispersing by ultrasonic, adding a porous nano material with the mass being 40-50% of that of the low-surface-energy modifier, continuing dispersing for 2 hours by ultrasonic, and then drying in a vacuum oven at the temperature of 60 ℃ to obtain a functional porous nano material;

step two, weighing the elastic polyurethane resin, the auxiliary agent, the solvent accounting for 70% of the total amount and the functional porous nano material prepared in the step one according to a formula, adding into a charging basket, and stirring for 5-45 min at a low speed (500-800 r/min) by using a high-speed dispersion machine;

step three, adding the wear-resistant filler into the mixture obtained in the step two, and stirring at a high speed (1200-1500 r/min) for 15-60 min; uniformly stirring, grinding for 0.5-4 h until the fineness of the coating is reduced to below 40 mu m, and finally adding the residual solvent to adjust the viscosity to obtain a component A;

and step four, mixing the component A and the component B before use, and uniformly stirring to obtain the anti-icing coating.

Example 1

The components and the corresponding mass fractions of the anti-icing coating for the low-temperature and high-humidity environment are shown in Table 1.

Table 1 composition by mass fraction of the anti-icing coating of example 1

The preparation method of the anti-icing paint comprises the following steps:

step one, adding 100g of ethanol solution into a three-neck flask, introducing nitrogen as protective gas, putting 5g of ethylene glycol aluminum salt and 45g of perfluoro ethylene propylene copolymer into the ethanol solution, adding 22.5g of porous nano-silica after uniform ultrasonic dispersion, continuing ultrasonic dispersion for 2 hours, and drying in a vacuum oven at 60 ℃ to obtain functional porous nano-silica;

step two, weighing the elastic polyurethane resin, the auxiliary agent, the solvent accounting for 70 percent of the total amount and the functional porous nano-silicon dioxide prepared in the step one according to a formula, adding into a charging basket, and stirring for 5min at a rotating speed of 800r/min by using a high-speed dispersion machine;

step three, adding wear-resistant filler into the mixture obtained in the step two, and stirring at the rotating speed of 1500r/min for 15 min; uniformly stirring, grinding for 3h until the fineness of the coating is reduced to below 40 mu m, and finally adding the residual solvent to adjust the viscosity to obtain a component A;

and step four, mixing the component A and the component B before use, and uniformly stirring to obtain the anti-icing coating.

Example 2

The components and the corresponding mass fractions of the anti-icing coating in example 2 are shown in table 2.

Table 2 composition by mass of the anti-icing coating of example 2

The preparation method of the anti-icing paint comprises the following steps:

step one, adding 100g of ethanol solution into a three-neck flask, introducing nitrogen as protective gas, putting 10g of aluminum isopropoxide and 40g of perfluorooctanoic acid into the ethanol solution, adding 16g of porous nano titanium dioxide after uniform ultrasonic dispersion, continuing ultrasonic dispersion for 2 hours, and drying in a vacuum oven at 60 ℃ to obtain functional porous nano titanium dioxide;

step two, weighing the elastic polyurethane resin, the auxiliary agent, the solvent accounting for 70 percent of the total amount and the functional porous nano titanium dioxide prepared in the step one according to a formula, adding into a charging basket, and stirring for 30min at a rotating speed of 650r/min by using a high-speed dispersion machine;

step three, adding the wear-resistant filler into the mixture obtained in the step two, and stirring at the rotating speed of 1350r/min for 40 min; uniformly stirring, grinding for 1h until the fineness of the coating is reduced to below 40 mu m, and finally adding the residual solvent to adjust the viscosity to obtain a component A;

and step four, mixing the component A and the component B before use, and uniformly stirring to obtain the anti-icing coating.

Example 3

The components and the corresponding mass fractions of the anti-icing coating in example 3 are shown in table 3.

Table 3 composition by mass of the anti-icing coating of example 3

The preparation method of the anti-icing paint comprises the following steps:

step one, adding 100g of ethanol solution into a three-neck flask, introducing nitrogen as protective gas, putting 7.5g of n-hexylaluminum salt and 42.5g of perfluorosilane into the ethanol solution, ultrasonically dispersing uniformly, adding 19g of carbon nano tube, continuing to ultrasonically disperse for 2 hours, and drying in a vacuum oven at 60 ℃ to obtain a functional carbon nano tube;

step two, weighing the elastic polyurethane resin, the auxiliary agent, the solvent accounting for 70 percent of the total amount and the functional carbon nano tube prepared in the step one according to a formula, adding the mixture into a charging basket, and stirring the mixture for 45min at a rotating speed of 500r/min by using a high-speed dispersion machine;

step three, adding wear-resistant filler into the mixture obtained in the step two, and stirring at the rotating speed of 1200r/min for 60 min; uniformly stirring, grinding for 2h until the fineness of the coating is reduced to below 40 mu m, and finally adding the residual solvent to adjust the viscosity to obtain a component A;

and step four, mixing the component A and the component B before use, and uniformly stirring to obtain the anti-icing coating.

Effects of the embodiment

The adhesion, the wear resistance, the contact angle, the shearing strength of the ice layer on the surface of the coating, the icing temperature on the surface of the coating and the like of the anti-icing coating prepared in the examples 1 to 3 are respectively detected according to GB/T5210-2006, GB/T1768-2006, GB/T30696-2014, GB/T7124-2008 and DSC test methods. The results of performance tests of the anti-icing coatings prepared in examples 1-3 are shown in Table 4.

TABLE 4 results of testing the performance of the anti-icing coatings prepared in examples 1 to 3

Serial number	Item	Inspection method	Example 1	Example 2	Example 3
						1	Adhesion force, MPa	GB/T5210-2006	8	7	7
2	Abrasion resistance (500g/500 rev), mg	GB/T1768-2006	37	41	31
						3	Contact angle, ° c	GB/T30693-2014	121	118	128
4	Shear strength of ice layer on the surface of coating layer, Mpa	GB/T7124-2008	1.45	1.24	1.32
						5	Freezing temperature of the coating surface, DEG C	DSC test	-8.3	-7.3	-7.6

As can be seen from Table 4, the anti-icing coatings prepared in examples 1 to 3 have adhesion, abrasion resistance, contact angle, shear strength of the ice layer on the surface of the coating, and icing temperature all meeting the requirements of anti-icing coatings for low-temperature and high-humidity environments, and have excellent anti-icing performance.

In addition to the performance detection, a coating prepared by using the coating and the polyurethane coating in the prior art is tested in a low-temperature wind tunnel at the temperature of-25 ℃ for 30min, and the result shows that the ice amount on the surface of the coating prepared by using the coating is far less than that of the coating prepared by using the polyurethane coating in the prior art, because most of water vapor is accumulated on the surface of the anti-icing coating in the initial stage of the test and then slides off the surface, only a small amount of ice crystals are formed, and the ice layer is slowly formed on the surface of the coating along with the time extension.

The anti-icing coating prepared by the invention is a two-component chemical reaction curing coating, can be coated by two-component high-pressure airless spraying, high-pressure air spraying, roller coating or brush coating, and is recommended to be coated to be 100 mu m in thickness.

The foregoing is merely a preferred embodiment of the invention and is not to be construed as limiting the invention in any way. All equivalent changes or modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.

Claims (9)

1. The anti-icing coating for the low-temperature high-humidity environment is characterized by comprising a component A and a component B, wherein the component A comprises the following components in percentage by mass:

45-65 wt% of polyurethane resin;

10-20 wt% of functional porous nano material;

17-25 wt% of wear-resistant filler;

10-15 wt% of a solvent;

2-3 wt% of an auxiliary agent;

the component B is an isocyanate curing agent;

the mass ratio of the component A to the component B is (5-5.5) to 1.

2. The anti-icing coating for low-temperature and high-humidity environment according to claim 1, wherein: the polyurethane resin is hydroxyl-containing polyurethane resin.

3. The anti-icing coating for low-temperature and high-humidity environment according to claim 1, wherein: the preparation method of the functional porous nano material comprises the following steps: adding 100g of ethanol solution into a container, introducing nitrogen as a protective gas, putting 5-10 g of organic metal alkoxide and 40-45 g of low-surface-energy modifier into the ethanol solution, performing ultrasonic dispersion uniformly, adding a porous nano material with the mass being 40-50% of the mass of the low-surface-energy modifier, continuing to perform ultrasonic dispersion uniformly, and then putting the porous nano material into a vacuum oven at the temperature of 60 ℃ for drying to obtain the functional porous nano material.

4. The anti-icing coating for low-temperature and high-humidity environment according to claim 3, wherein: the organic metal alkoxide is any one of ethylene glycol aluminum salt, isopropanol aluminum salt and n-hexanol aluminum salt.

5. The anti-icing coating for low-temperature and high-humidity environment according to claim 3, wherein: the low surface energy modifier is any one of perfluorosilane, perfluorooctanoic acid and a perfluoroethylene-propylene copolymer.

6. The anti-icing coating for low-temperature and high-humidity environment according to claim 3, wherein: the porous nano material is any one of porous nano silicon dioxide, porous nano titanium dioxide and carbon nano tubes.

7. The anti-icing coating for low-temperature and high-humidity environment according to claim 1, wherein: the wear-resistant material is any one or two of alumina, zirconia, glass beads and polytetrafluoroethylene powder.

8. The anti-icing coating for low-temperature and high-humidity environment according to claim 1, wherein: the solvent is any one or more of dimethylbenzene, acetone, n-butanol and ethyl acetate.

9. A method for preparing an anti-icing coating for a low-temperature high-humidity environment is characterized by comprising the following steps:

adding an ethanol solution into a three-neck flask, introducing nitrogen as a protective gas, putting 5-10 g of organic metal alkoxide and 40-45 g of low-surface-energy modifier into the ethanol solution, uniformly dispersing by ultrasonic, adding a porous nano material with the mass being 40-50% of that of the low-surface-energy modifier, continuously dispersing by ultrasonic uniformly, and then putting the mixture into a vacuum oven at the temperature of 60 ℃ for drying to obtain a functional porous nano material;

step two, weighing the elastic polyurethane resin, the auxiliary agent, the solvent accounting for 70% of the total amount and the functional porous nano material prepared in the step one according to a formula, adding into a charging basket, and uniformly stirring at a low speed by using stirring equipment;

step three, adding the wear-resistant filler into the mixture obtained in the step two, and uniformly stirring at a high speed; uniformly stirring, grinding for 0.5-4 h until the fineness of the coating is reduced to below 40 mu m, and finally adding the residual solvent to adjust the viscosity to obtain a component A;

and step four, mixing the component A and the component B before use, and uniformly stirring to obtain the anti-icing coating.