KR101973961B1 - Coating agent composition for preventing the attachment of marine organisms - Google Patents

Abstract

We propose a coating agent for marine life prevention using carbon nanotubes that is eco-friendly and has a long-lasting effect of preventing the attachment of marine organisms. The coating material is composed of a base material, a middle material and a top material. The middle material and the top material include a silicone compound in an amount of 60 to 80% by weight based on the total coating material. The top material includes 1 to 5% And 15 to 25% by weight of a ceramic powder, and the carbon nanotube is a cost-effective antibacterial substance which is not ionized in water.

Description

TECHNICAL FIELD The present invention relates to a coating agent for preventing adhesion of marine organisms using carbon nanotubes,

The present invention relates to a coating agent for preventing adhesion of marine life, and more particularly, to a coating agent for preventing adhesion of marine organisms such as barnacles, mussels, parasites and the like using carbon nanotubes.

In general, aquatic microorganisms grow after forming a biofilm in the ocean, acquiring nutrients, and maintaining cellular enzymatic activity and sharing metabolism with other microorganisms. For this purpose, it attaches to rocks, concrete, artificial structure, metal surface and forms a film and attaches to it. These marine organisms secrete polysaccharides as well as nucleic acids, fatty acids, and proteins, and many biofilms form in the process of mutual interaction of these substances and microorganisms. Biofilms of these microorganisms grow on marine organisms such as barnacles and mussels.

Thermal power and nuclear power plants use large amounts of seawater as cooling water. The layer of adherent organisms and jellyfish that drift like plankton together with seawater enter the cooling water channel of the power plant and live in power generation facilities such as various suction pipes, pipelines and turbines. The attachment and formation of these marine organisms deteriorate the function of the power generation facility or cause many obstacles to various parts constituting the facility. Concretely, if the attached creatures represented by the barnacles and the red sea flies are adhered to the inside of the cooling water of the power plant, they may cause the closure and corrosion of the water channels. This results in serious problems such as reduced water withdrawal and reduced efficiency in converting water vapor to water.

In the power plant, various measures are being taken to prevent adhesion, such as application of antifouling paint, injection of chlorine generated by electrolysis of seawater, and cleaning of pipe by sponge balls. In the case of antifouling paints, hazardousness to organic antifouling components is becoming more important as the environment becomes more important, and TBT (tributyltin), which has been used so far as an antifouling component, is prohibited from being used due to environmental hormones. Also, inorganic substances such as ash, which is generally used as an anti-fouling additive, are highly toxic and thus regulated in environmental aspects.

In order to avoid the above environmental regulations, Korean Patent No. 10-1424283 and Korean Patent No. 10-41750 disclose an antifouling composition prepared by mixing silver chloride, silver nitrate, organic acid metal salt and metal components. However, according to the patent, it is difficult to completely solve the problem in the environmental aspect, and the antifouling effect is not continuous. Accordingly, there is a demand for a coating agent for prevention of attachment of marine life that is long-lasting in an antifouling effect that is eco-friendly and prevents attachment of marine life.

The object of the present invention is to provide a coating agent for preventing adhesion of marine organisms using carbon nanotubes that is environmentally friendly and maintains the effect of preventing the attachment of marine organisms for a long time.

In order to solve the problems of the present invention, a coating agent for preventing adhesion of marine organisms using carbon nanotubes is composed of a base material, a middle material and a top material, wherein the middle material and the top material are coated with a silicone compound in an amount of 60 to 80% Wherein the topcoat comprises 1 to 5% by weight of carbon nanotubes, 5 to 20% by weight of silicone oil, and 15 to 25% by weight of ceramic powder with respect to the total coating agent, wherein the carbon nanotubes are non- It is an antibacterial substance.

In the coating agent of the present invention, the silicone compound is preferably polydimethylsiloxane. The carbon nanotubes may be any one of multi-wall carbon nanotubes or single-wall carbon nanotubes or a mixture thereof. The carbon nanotubes may be supported on the ceramic powder or may be mixed with the ceramic powder. The ceramic powder may be at least one selected from MCM mesoporous materials (MCM-41, MCM-48), silicates such as zeolite, clay, titanium oxide, silica, talc, calcium carbonate and mica.

In the preferred coating material of the present invention, the topsheet may further contain 5 to 80% by weight of copper sulfide, which is a cost-effective antibacterial material that is not ionized in water, based on the carbon nanotubes. The copper sulfide may be coated on the surface of the ceramic powder.

According to the coating agent for preventing adhesion of marine organisms using the carbon nanotubes of the present invention, the effect of preventing the attachment of marine organisms is maintained for a long time by utilizing carbon nanotubes. Carbon nanotubes and copper sulfide, which may be added, are cost-effective and environmentally friendly.

The photographs taken after coating the coated samples of Examples and Comparative Examples of the present invention in Fig. 1 for 3 months in seawater.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The embodiments described below can be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below. The embodiments of the present invention are provided to enable those skilled in the art to more fully understand the present invention.

An embodiment of the present invention provides a coating agent for preventing adhesion of marine organisms that is environmentally friendly and retains the effect of preventing the attachment of marine organisms for a long time by utilizing carbon nanotubes. To this end, the composition of the coating agent will be described in detail, and the environment-friendly effect of the composition and the effect of preventing the attachment of marine organisms will be described in detail. The coating agent of the embodiment of the present invention is applied to a power generation facility of a power plant, and various power generation facilities include a suction pipe, a pipe, and a turbine.

The coating material of the present invention is composed of a lower material / a middle material / a top material. The undercoating resin is used to smoothly adhere to a power generation facility. For example, Bisphenol-A type is used, and it contains 15 to 35% by weight based on the total coating agent. The curing agent of the undercoat is polyamide and polyamide adduct type and contains 10 to 30 wt% based on the total coating agent. A silicone compound is applied to the intermediate member, and the upper member includes a silicon compound and carbon nanotubes, and the silicone agent contains 5 to 20 wt% of silicone oil relative to the entire coating agent.

The silicone compound is preferably polydimethylsiloxane, and the silicone material of the intermediate member and the topcoat contains 60 to 80% by weight based on the total coating agent. The carbon nanotubes are contained in an amount of 1 to 5% by weight based on the total coating agent. That is, the content of the silicone compound is 60 to 80 wt%, the amount of the silicone oil is 5 to 20 wt%, and the amount of the carbon nanotube is 1 to 5 wt%.

The coating agent of the present invention is characterized by a composition comprising an antimicrobial composition containing carbon nanotubes as an antibacterial and sterilizing material, a silicone compound controlling surface properties, and a silicone oil as essential components. That is, the topsheet of the coating agent according to the present invention includes a silicone compound, a silicone oil, an antimicrobial composition and other additives. The silicon compound is, for example, a hydrocarbon compound containing a silicon (Si) atom. The bonding group of silicon (Si) atoms of the silicon compound is a polar group selected from a hydroxyl group, an alkoxy group having 1 to 10 carbon atoms, an amide group, Substituted or unsubstituted. Specific examples of such a silicone compound include those selected from 2- (trimethylsilyloxy) ethyl methacrylate, tris (3-methacryloxypropyl) silane, 3-tris (trimethylsiloxy) silylpropyl methacrylate and polydimethylsiloxane Or more.

If the content of the silicone compound is too small, the effect of increasing the contact angle of the coated surface can not be expected. If the content of the silicone compound is too high, If it is included, the hydrophilicity is rapidly lowered and the hardness becomes too large, so that the surface is hard and can break well. The silicone compound is environmentally friendly, stable in seawater, and has a large contact angle on the surface to prevent marine organisms from sticking.

The silicone oil is intended to further increase the lubricity of the surface of the coating agent. If the amount is less than 5% by weight based on the total coating agent, the effect of the silicone oil can not be obtained. If it is larger than 20% by weight, the strength of the coating film by the coating agent is lowered. The silicone oil is not necessarily limited thereto, but it is possible to supplement the function of the silicone oil, such as attaching a silanol or carbolic group to the terminal group. For example, it is possible to increase the slip property by attaching a CH ₂ OH group end group.

The antimicrobial composition is intended to prevent the attachment of marine organisms by sterilization and antibacterial, and there are an elution type and an expulsion type. The dissolution type is an organic type, an organometallic type, an inorganic type having antifouling performance singly or in combination, and a variety of organic and high molecular weight type binders are used. Thereby continuously imparting antifouling performance by abrasion and elution. Copper, zinc or their oxides gradually ionized in seawater to obtain antimicrobial effect. However, copper is a contaminant designated as a soil pollutant in the Soil Environment Conservation Act (1995), and the toxicity of zinc is relatively low According to the Ministry of Health and Social Affairs Environmental Conservation Law Examination, it causes headache and diarrhea at 5 ~ 6ppm and life risk at 1,000ppm. The permissible water limit is set at less than 1 mg / l for water quality standards and less than 5 mg / l for emission standards. In addition, the silver ions (Ag +) presented in conventional dissolution type antimicrobial compositions are classified as environmentally nano-toxic ions.

As described above, the substance to be applied to the dissolution type has a serious adverse effect on the underwater environment. In order to solve the problem of the dissolution type coating agent, the coating agent according to the embodiment of the present invention is applied to a coating agent by dissolving in water and not ionizing the costly antimicrobial material. Accordingly, an antimicrobial composition containing a cost-effective carbon nanotube as a sterilizing and antibacterial substance, a silicone compound for controlling surface properties and a silicone oil are essential components. The antimicrobial composition is composed of a carbon nanotube and a ceramic powder, and is mixed with a silicone compound. That is, adhesion is prevented by using the characteristics of a silicon compound having a smooth surface, and the propagation of microorganisms in contact with the carbon nanotubes, which are antimicrobial substances mixed in the silicone compound, is prevented.

The carbon nanotubes according to the embodiment of the present invention are formed into a tubular shape by connecting six hexagons of carbon. The diameter of the tube is only a few to several tens of nanometers, and the nanometer is 1/100 millionth of a meter, usually one-tenth the thickness of hair. The electrical conductivity of carbon nanotubes is similar to that of copper. The thermal conductivity is the highest in nature, and its strength is 100 times better than steel. The carbon nanotubes of the present invention can be applied to multi-walled carbon nanotubes (MWNTs) or single-walled carbon nanotubes (SWNTs). These carbon nanotubes have antimicrobial properties, as is well known, and prevent adhesion of microorganisms and marine organisms to a power plant.

The carbon nanotube is a biocompatible material capable of minimizing water pollution, for example, MCM mesoporous material (MCM-41, MCM-48), zeolite, clay, titanium oxide, silica, talc, calcium carbonate, May be carried on or mixed with one or more ceramic powders selected from the same silicates. The ceramic powder carrying the carbon nanotubes is a porous body. As described above, the carbon nanotubes carried or mixed in the porous ceramic powder are mixed together with the silicon compound, and coated on the power generation equipment, which is a coating, to form a composite coating film.

Optionally, copper sulphide can be added as an antimicrobial agent. The chemical structure of copper sulfide is hexagonal crystal of Cu _x S _y , and the ratio of x / y is 0.8 to 1.5. The x / y ratio of 0.8 to 1.5 is a condition for forming a hexagonal crystal structure of copper sulfide. When the binding ratio of x / y is less than 0.8, the concentration of sulfur (S) becomes excessively high and the antibacterial property is good. Chemical stability does not form a crystal structure. When it exceeds 1.5, the concentration of sulfur (S) decreases and the antibacterial property is lowered. The copper sulfide may be coated on itself or the ceramic powder by various methods such as wet coating, plating, and vapor deposition to be mixed with the silicate compound. Such copper sulfide functions as a cost expulsion according to the embodiment of the present invention.

The antibacterial activity of the specimens was evaluated by measuring the number of bacteria after incubating the test bacteria at 25 ° C for 24 hours using Escherichia coli (ATCC 25922) as a strain. It is sterilized or sterilized at a level of 10 ⁴ to 10 ⁶ according to the content of copper sulfide. If there is no copper sulfide, it is 10 ¹⁰ . Particularly, when copper sulfide is coated on the ceramic powder, the antibacterial property is increased as compared with the case where the ceramic powder is dispersed in the ceramic powder.

The antifungal agent according to the embodiment of the present invention is 1 to 5% by weight based on the total coating agent. When the amount is less than 1% by weight, the antifouling effect is deteriorated. When the amount is more than 5% by weight, Is relatively low. On the other hand, carbon nanotubes are relatively expensive and it is not preferable to use more than 5 wt%. At this time, the amount of copper sulfide is preferably 5 to 80% by weight based on the carbon nanotubes. If it is less than 5% by weight, the antibacterial effect by the copper sulfide is insignificant. If it is more than 80% by weight, the content of the carbon nanotubes is excessively reduced, thereby reducing the antibacterial effect by the carbon nanotubes. In addition, the ceramic powder is 15 to 25% by weight based on the total coating agent, and when the amount is outside the above range, the coating fluidity is high or low, so that the coating operation is difficult.

The other additives to be mixed with the coating agent of the present invention constitute the remaining contents and include plasticizers, surface conditioners, dispersants, antifoaming agents, leveling agents, coupling agents and the like, and detailed descriptions thereof will be omitted here . In some cases, antimicrobial agents of the elution type may be added to the extent permitted by environmental standards. An embodiment of the present invention has added zinc pyrithione.

The coating according to the present invention is coated on a power plant to form a thin curable coating layer. The coating layer has lipophilic and hydrophilic reactors derived from a silicone compound and chemically adsorbs moisture by a hydrophilic reactor to change the contact angle. Further, the coating layer of the present invention does not affect the physical properties of the power generation facility, and is a non-emissive type, so that the antifouling characteristics are continuously maintained.

Hereinafter, the following examples will be presented in order to explain the physical properties of the coating agent for preventing marine organism adhesion of the present invention in detail. However, the present invention is not particularly limited to the following examples. At this time, the contact angle (˚) was measured by model name MSA (manufacturer, KRUSS), and the degree of barnacle and seaweed adhesion was visually determined.

≪ Examples 1 and 2 >

In Examples 1 and 2 of the present invention, the polydimethylsiloxane (Shin-Etsu Silicon) of a middle material and a top material was set to 66 wt% and 75 wt%, respectively, relative to the total coating agent, and 10 wt% of silicone oil (Dow Corning) 20% by weight of ceramic powder, and 3% by weight of carbon nanotubes (Wonil Corporation). After the coating agent was prepared, it was coated on a PVC panel. At this time, the ceramic powder was suitably mixed with at least one of titanium oxide, silica, talc, calcium carbonate, mica and layered silicate. Thereafter, the contact angle of the sample, the barnacle and the degree of attachment of the seaweed were confirmed.

≪ Examples 3 and 4 >

The contact angle and adhesion degree of the coating layer were confirmed in the same manner as in Example 1, except that the carbon nanotubes were 1 wt% and 5 wt%, respectively, with respect to the total coating agent.

≪ Comparative Examples 1 to 3 >

In Comparative Example 1, the contact angle and adhesion degree of the coating layer were measured by the same method as in Example 1 except that the product of the IPK company in the Netherlands, the product of the Danish Hempel Company of Comparative Example 2, and the product of Chukoku Corporation of Comparative Example 3, Respectively. Comparative Examples 1 to 3 do not contain carbon nanotubes.

≪ Comparative Examples 4 and 5 >

The contact angle and adhesion degree of the coating layer were confirmed in the same manner as in Example 1, except that the carbon nanotubes were 0.5 wt% and 7 wt%, respectively, with respect to the total coating agent.

Table 1 shows the physical properties of the coating layers of Examples 1 to 4 and Comparative Examples 1 to 5 of the present invention. 1 is a photograph of Examples 1 and 2 and Comparative Examples 1 and 3 after 3 months in seawater. The contact angle is an average value obtained by a plurality of measurements rather than a single measurement. X indicates a state in which adhesion hardly occurs, & cir & indicates a state in which adhesion is established but not solidified, and &

division Contact angle Barnacles and seaweed attachments Example 1 100 × Example 2 101 ○ Example 3 98 × Example 4 96 × Comparative Example 1 94 ◎ Comparative Example 2 100 ◎ Comparative Example 3 90 ◎ Comparative Example 4 99 ◎ Comparative Example 5 85 ◎

According to Table 1, in Examples 1 to 4 and Comparative Examples 4 and 5, the silicone oil and the ceramic powder were fixed at 10 wt% and 20 wt%, respectively, in order to compare physical properties between the silicon compound and the carbon nanotube. The contact angles of Examples 1 and 2 were 100 degrees and 101 degrees, respectively, and the contact angles of Comparative Examples 2 and 3 were large. The larger contact angle can be attributed to the effect of polydimethylsiloxane and silicone oil. Particularly, it was confirmed that the polydimethylsiloxane which is the silicone compound of Examples 1 and 2 of the present invention is a good material for smoothing the surface of the coating agent.

In Examples 3 and 4, although 1 wt% and 5 wt% of carbon nanotubes were respectively added, there was no significant difference compared to the contact angles of Comparative Examples 1 to 3. Maintains a large contact angle due to the influence of polydimethylsiloxane and silicone oil. Accordingly, 1 to 5% by weight of the carbon nanotubes can be sufficiently utilized for the coating agent according to the embodiment of the present invention.

The color of the sample was close to the original white or weakly discolored (see photographs of Examples 1 and 2 in Fig. 1) because the barnacle of Examples 1 to 4 and the attachment of seaweeds did not occur or were not adhered. That is, in Examples 1 to 4, it was confirmed that there was almost no adhesion of barnacle and seaweed. On the other hand, since the barnacles and seaweeds of Comparative Examples 1 to 4 were adhered to each other, the color of the sample turned yellow. In the case of Comparative Examples 1 to 3, since there is no antimicrobial substance such as carbon nanotubes, it is difficult to prevent adhesion of microorganisms in the water. In Comparative Example 4, the content of carbon nanotubes was so small that the attachment of the barnacle and seaweed could not be prevented. In Comparative Example 5, it is possible to prevent the attachment of the barnacle and the seaweed, but the contact angle is small and the adhesion of the barnacle and seaweeds is likely to occur with the lapse of time.

The coating agent according to the embodiment of the present invention is difficult to attach and propagate marine organisms including aquatic microorganisms due to the slippery surface because the coating layer coated on the power generation facility has a contact angle in water of more than 90 degrees and more than 100 degrees. Even if marine organisms are attached, the antimicrobial effect of being sterilized or sterilized by the carbon nanotubes, copper sulfide or a mixture thereof contained in the coating agent of the present invention is exerted, so that the propagation of marine organisms including aquatic organisms can be prevented. In addition, the coating agent of the present invention can be said to be environmentally friendly because it does not dissolve copper ions, zinc ions, silver ions, and the like, which are existing environmental toxicity, in water.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but many variations and modifications may be made without departing from the spirit and scope of the invention. It is possible.

Claims (7)

It is made of undercoat material, middle material and top material,
The intermediate material and the topcoat material may include 60 to 80% by weight of the silicone compound based on the total coating material,
Wherein the top coat comprises 1 to 5% by weight of carbon nanotubes, 5 to 20% by weight of silicone oil and 15 to 25% by weight of ceramic powder with respect to the total coating agent,
The carbon nanotube is a cost-effective antibacterial substance that is not ionized in water,
Wherein the topsheet comprises 5 to 80% by weight of copper sulfide, which is a cost-effective antibacterial material that is not ionized in water, on the carbon nanotubes, and the copper sulfide is coated on the surface of the ceramic powder. A coating agent for preventing adhesion of marine organisms using. The coating agent for preventing adhesion of marine organisms using carbon nanotubes according to claim 1, wherein the silicone compound is polydimethylsiloxane. The coating agent for preventing adhesion of marine organisms using carbon nanotubes according to claim 1, wherein the carbon nanotubes are any one selected from multi-wall carbon nanotubes or single wall carbon nanotubes or a mixture thereof. The coating agent for preventing adhesion of marine organisms using carbon nanotubes according to claim 1, wherein the carbon nanotubes are supported on the ceramic powder or mixed with the ceramic powder. The ceramic powder according to claim 1, wherein the ceramic powder is at least one selected from MCM mesoporous materials (MCM-41, MCM-48), zeolite, clay, titanium oxide, silica, talc, calcium carbonate, Coated with carbon nanotubes.

delete delete

Images