JPS60170673A - Coating agent for material contacting with water - Google Patents

Abstract

PURPOSE:To provide the titled coating agent for ships, fixed shore nets, etc., containing a copolymer composed of a specific monomer, a polymerizable unsaturated carboxylic acid and a hydrophobic polymerizable unsaturated monomer at specific ratios, releasing the coating agent at a moderate rate without using toxic substance, and effective to prevent the adhesion of aquatic life. CONSTITUTION:The objective coating agent contains a copolymer obtained by the copolymerization of (A) 5-75wt% monomer of formula [R<1> is H, CH3 or CH2COO(CmH2m)nR<2>; R<2> is H or 1-28C hydrocarbon group; m is 2-4; n is 1- 200], (B) 3-55% polymerizable unsaturated carboxylic acid or its salt and (C) 15-80% hydrophobic polymerizable unsaturated monomer. USE:Coating of bridge, cooling water system of power plant, culture net, buoy, etc.

Description

Detailed Description of the Invention [Technical Field of the Invention] The present invention relates to a coating agent for materials that come into contact with water, and more specifically, a coating agent that gradually dissolves in water to prevent aquatic organisms and other substances from adhering to materials that come into contact with water. The present invention relates to a coating material for coating.

[Prior art]

Aquatic organisms such as algae and shellfish and other deposits adhere to materials that come into contact with freshwater or seawater, such as materials used in water, causing various problems.

Traditionally, it has been used as a coating to prevent aquatic organisms from adhering to it.
Antifouling paints, coatings containing toxic compounds such as organotin compounds and cuprous oxide, have been used. Although this antifouling paint is quite effective in preventing the adhesion of aquatic organisms, it has the disadvantage that toxic compounds elute and pollute nearby water bodies. In addition, although the resins used in antifouling paints are resins that elute in water, their elution rate is low, so if they do not contain toxic compounds,
It has the disadvantage that it cannot prevent attachment of aquatic organisms.

[Purpose of the invention]

The present invention has been made to improve the above-mentioned drawbacks.
By using a specific copolymer as a coating material, the coating material can be eluted at a moderate rate without using toxic substances, effectively preventing the attachment of aquatic organisms and other substances, and ensuring that the coated surface is always kept clean. The object is to provide a coating for materials in contact with water that can maintain a uniform surface condition.

[Structure of the invention]

This invention comprises (A) 5 to 75 weight percent of the monomer represented by the general formula (1);
, R' CH2=CC0○(Cm H2mO)n R2""'(
]) (wherein, R1 is H, CI+3 or CI 2 CC00(Ct12mO)nR2, R2 is H
or a hydrocarbon group having 1 to 28 carbon atoms, m is an integer of 2 to 4, and n is 1 to 200. ) (B) Polymerizable unsaturated carboxylic acid or its salt 3-55
Weight%, and (C): Hydrophobic polymerizable unsaturated monomer 15-80 weight%
A coating agent for materials that come into contact with water, characterized in that it contains a copolymer of .

In the present invention, materials that come into contact with water are materials to which deposits adhere when coming into contact with water such as freshwater or seawater, such as ships, bridges, tanks, cooling water systems of power plants, aquaculture nets, fixed nets, etc. There are materials used underwater or near the surface of the water, such as floats. In addition, the main targets for control are aquatic organisms such as algae and shellfish, but in addition to these, slime, scale, and other dirt that adhere to materials that come in contact with water can also be removed. is the target.

In the general formula (1), the hydrocarbon group represented by R'' includes a methyl group, an ethyl group, an allyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a tert-butyl group, an amyl group, an isoamyl group, hexyl group, heptyl group, 2-ethylhexyl group, octyl group, nonyl group,
Decyl group, undecyl group, lauryl group, tridecyl group,
myristyl group, cetyl group, isocetyl group, stearyl group, instearyl group, oleyl group, octyldodecyl group, behenyl group, decyltetradecyl group, benzyl group, cresyl group, butylphenyl group, dibutylphenyl group, octylphenyl group, nonyl Examples include alkyl groups, alkenyl groups, and alkylphenyl groups such as phenyl group, lauryl phenyl group, dioctylphenyl group, dinonylphenyl group, and styrenated phenyl group.

Examples of the oxyalkylene group represented by CnlH2mO include oxyethylene group, oxypropylene group, oxybutylene group, and oxytetramethylene group.

Component (A) is a water-soluble monomer, which includes acrylic acid, methacrylic acid, or itaconic acid, ethylene oxide, propylene oxide, which is an alkylene oxide having 2 to 4 carbon atoms,
A compound to which 1 to 200 moles, preferably 1 to 30 moles of butylene oxide or tetrahydrofuran is added per carboxyl group, or a compound having 1 to 28 carbon atoms,
Preferred examples include 1 to 22 alkyl ethers, alkenyl ethers, and alkylphenyl ethers.

When the number of moles of alkylene oxide added exceeds 200 moles, the copolymerization reaction becomes difficult to occur, and alkyl ether,
When the number of carbon atoms in the hydrocarbon group of the alkenyl ether or alkylphenyl ether exceeds 28, water solubility decreases.

Component (B) is also a water-soluble monomer, including dibasic acids such as acrylic acid, methacrylic acid, and crotonic acid, dibasic acids such as maleic acid, fumaric acid, and itaconic acid, and carbon atoms of these dibasic acids ranging from 1 to 1.
In addition to 22 alkyl or alkenyl monoesters, lithium salts and sodium salts of their carboxylic acids,
Examples include potassium salts, ammonium salts, alkylamine salts having 1 to 4 carbon atoms, monoethanolamine salts, jetanolamine salts, and 1-liethanolamine salts.

Component (C) is a hydrophobic monomer, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate-1-, amyl (meth)acrylate, hexyl (meth)acrylate. acrylate, heptyl(meth)acrylate-1, octyl(meth)acrylate, nonyl(meth)acrylate-1-, decyl(meth)acrylate-1-, dodecyl(meth)acrylate, te-radecyl(meth)acrylate, Hexadecyl (meth)acrylate, octadecyl (meth)acrylate, oleyl (meth)acrylate, cyclohexyl (meth)acrylate, vinyl acetate, styrene, α
- Methylstyrene, acrylonitrile, vinyl chloride, butadiene, chloroprene, etc. In the present invention,
[(Meth)acrylates' refers to both acrylates and methacrylates.

The polymer used as the coating material of the present invention contains 5 to 75% by weight of component (A), 3 to 55% by weight of component (B), and (
C) component 15-80%, preferably component (A) 10%
~70% by weight, (B) component 5-50% by weight, and (C
) is a copolymer containing 20 to 75 percent of the component. (A)～(
Each of the components in C) may be used alone or in combination of two or more of the above-mentioned exemplified or non-exemplified components. The water solubility, strength, flexibility, etc. of the polymer can be adjusted by appropriately selecting the types and proportions of each component and the molecular weight of the polymer.

Both components (A) and (B) impart appropriate water solubility to the coating material, and in order for the coating material to dissolve uniformly in water, it is necessary for both components to exist in a certain proportion. . (A
), (B) If both components are larger than the above range, the solubility in water becomes too large, which is undesirable.
If it is smaller than the above range, the elution rate will be too small and the antifouling effect will be small, and if only component (A) is smaller than the above range, the elution rate of the coating material will be uneven depending on the location, causing unevenness and craters on the surface. If only component (B) is smaller than the above range, the elution rate with respect to water will become faster or slower.

Component (C) is necessary to impart strength and flexibility and to adjust dissolution properties; if it is larger than the above range, the dissolution properties will be reduced, and if it is smaller than the above range, the strength or flexibility will be reduced, and Dissolution becomes too large.

The polymer of the present invention can be easily obtained by subjecting a mixture of components (A), (B) and (C) to solution polymerization, emulsion polymerization or suspension polymerization in the presence of a radical catalyst.

The smaller the molecular weight of the polymer, the higher the elution rate into water, but in order to have an appropriate elution rate, the weight average molecular weight should be 5.
000 to 500,000, preferably 10,000 to 300,000.

The coating material of the present invention may contain one of the above polymers,
Depending on the difference in the components (A) to (C), two or more kinds may be included. The coating may also contain solvents, stabilizers and other ingredients.

The coating material of the present invention is obtained by applying a polymer solution as it is or diluting it with an appropriate solvent to a material that comes into contact with water by a conventional method such as spraying or brushing to form a film.
Prevents the adhesion of deposits.

The painted coating material has appropriate strength and flexibility, and elutes at an appropriate rate to prevent attachment of aquatic organisms, etc., and the elution rate is uniform and constant, and large amounts of elution occur locally. There is no change in the elution rate over time, and the coated surface is always kept in a uniform state.

〔Effect of the invention〕

As described above, according to the present invention, since a specific copolymer is used, it is possible to prevent organisms from adhering to materials that come into contact with water without using toxic substances, and to keep the coated surface constant. A uniform surface condition can be maintained.

[Embodiments of the invention]

Next, the present invention will be explained using production examples, test examples, and comparative examples. Note that "part" indicates a polymerized part. Moreover, the components (A) to (C) used in the test examples are as shown below.

(A) Component: ■ Pentaoxypropylene glycol monomethacrylate H Tetradecaoxypropylene glycol monomethacrylate III Methoxytetraoxyethylene methacrylate-1
~ ■ Methoxynonaoxyethylene methacrylate-V Methoxytricosaoxyethylene methacrylate ■ Octaoxyethylene glycol monomethacrylate ■ Methoxyheptaoxypropylene nonaoxyethylene methacrylate (block copolymer) ■ 2-Hydroxybubutyrmethacrylate lX2-hydroxyethyl Methacrylate X 2-Hydroxyethyl acrylate CH2=CHC00C2H40H XI Methoxynonaoxyethylene acrylate CH2
=CHC00(C2H40)9 CHaXII bis(methoxydecaoxyethylene) itaconate XIII octadecyloxytricosaoxyethylene methacrylate (B) component: Methacrylic acid (MA) Acrylic acid (AA) (C) component: Methyl methacrylate (MMA) Butyl methacrylate (BMA) Cyclohexyl methacrylate (CMA) Lauryl methacrylate (LMA) Stearyl methacrylate (SMA) Ethyl acrylate (EA) Butyl acrylate (BA) Styrene (ST) Acrylonitrile (AN) Vinyl chloride (VC) Vinyl acetate (VAC) ) Production Example 1 In a four-bottle flask, 50 parts of pentaoxypropylene glycol monomethacrylate (■ of the above (A) component) as the (A) component, 5 parts of methacrylic acid as the (B) component, (
45 parts of methyl methacrylate as component C) 0.5 parts of N,N'-azobisisobutyronitrile as polymerization initiator
1 part and 400 parts of the solvent isopropanol were taken, and a polymerization reaction was carried out at the reflux temperature of the isopropanol in a nitrogen gas atmosphere for 16 hours. The obtained polymer (NQI) was a homogeneous transparent liquid with a slightly high viscosity. A part of this polymer solution was concentrated to a concentration of 50 wt.
The viscosity was X when measured using a bubble viscometer at 25°C according to the ``Kinematic Viscosity'' in ``General Test Methods for Paints''. Also,
The number average molecular weight of this polymer determined by gel permeation chromatography was 13,500, and the weight average molecular weight was 52,900. This polymer solution was applied onto a stainless steel plate and dried to obtain a coating film with a thickness of 3 μm.
The hardness of K 5400 measured by Pencil Scratch Test J was H.

Table 1 below shows the properties of polymers obtained by reacting the components (A), (B), and (C) in Table 1 in the proportions shown in Table 1.
Also listed in In addition, in the viscosity measurement, polymer Nα5~N
Since α7 does not form a homogeneous solution at 25° C., it was measured after distilling off Impropatool and making a 5% toluene solution.

Production example 2 In a sealed tube ampoule with an inner diameter of 20 mm and a length of 200 mm,
Take 100 parts of the monomer shown in Table 2, 0.5 part of N,N'-azobisisobutyronitrile, and 400 parts of isopropanol, replace the air in the ampoule with nitrogen, and then melt-seal at 80°C. Polymerization was carried out by shaking for 16 hours.

The hardness was measured by ``Experiment\''. The results obtained are shown in Table 2.

Table 2 Note: * Neutralize the carboxyl groups of the polymer with an equivalent amount of potassium hydroxide 2 (continued) Table 2 (continued) Test Example 1 The solution of polymers Nα1 to Nα59 obtained in Production Example 1.2 was Coating and drying were repeated on one side of a stainless steel test plate 1 having a length of 100 mm and a width of 50 mm shown in FIG. As shown in Fig. 2, the stainless steel test plates 1 were arranged in a diameter of 350 mm with an interval of 100 mm.
It is fixed to a fixed frame 5 consisting of a stainless steel ring 3 and an arm 4, and as shown in FIG.
The coating film 2 was immersed in a container 7 filled with water, and then the water was stirred using a stirrer 8 installed in the center of the container 7, and an elution test was conducted for 30 days with the surface of the coating film 2 constantly being washed with a stream of water. Ta. The speed of water at this time was 10 cm/sec on the surface of the coating film 2. The test plate 1 was taken out after 1 day, 5 days, and 30 days of the test period, and after sufficiently drying, the weight was measured. After the weight measurement, the test plate 1 was immersed in the container 7 again during the test period to continue the test.

Assuming that the density of the polymer is 1 g/cm'', the amount of decrease in thickness per coating was calculated from the weight decrease of the coating film and the coated surface area using the following formula.

The results are shown in Table 3. If most of the coating was eluted within the test period, the number of days is indicated in parentheses. Furthermore, the coating film was uniformly eluted during the test period, and no pores were formed locally.

Table 3 Table 3 (Continued) Table 3 (Continued) Table 3 (Continued) Test Example 2 Seawater was used instead of the ion-exchanged water in Test Example 1.
Other conditions were exactly the same, and polymers Nα1 to Nα10
A dissolution test was conducted on the following. The results are shown in Table 4.

During the test period, the coating was uniformly dissolved and no localized pores were formed.

Table 4 Comparative Examples For the following nine polymers, prepare a 5% methanol solution or isopropanol solution, form a coating film on a stainless steel test plate in the same manner as Test Example 1, and perform an elution test with ion-exchanged water. I did this.

(1) Carboxymethyl cellulose Most of it was eluted within 6 hours.

(2) Methoxy-hydroxypropoxycellulose was mostly eluted after 7 hours.

(3) 1-lium polyacrylate Most of it was eluted within 4 hours.

(4) Polyvinyl alcohol (degree of saponification 80%) Most of the solution was eluted after 8 hours.

(5) Polyethylene oxide (molecular weight: 1,000,000) Most of the solution was eluted within 6 hours.

(6) Styrene-ammonium maleate copolymer was completely eluted within 1 hour.

(7) MA (25 parts) - MMA (75 parts) copolymer After 1 day, many irregularities appeared on the surface, and after 5 days, the diameter was 1~
Many crater-shaped holes of 5 mm+ were generated.

(8) (A)■ (60 parts)-8T (40 parts) copolymer (methacrylic acid in polymer Nα3 in Table 1 replaced with styrene) Test examples showing the amount of decrease in coating film thickness are shown in Figure 4. The results are shown in comparison with Polymer Na3 of No. 1.

(9) (A)■ (30 parts)-8T (70 parts) copolymer (methacrylic acid in polymer Nα53 in Table 2 replaced with styrene) The amount of decrease in coating film thickness is shown in Figure 5 as a test example. The results are shown in comparison with Polymer Nα53 of No. 1.

As is clear from the above results, Comparative Examples-(1) to (6)
) The dissolution rate of the commercially available water-soluble polymer compound is so high that the coating film is eluted in several hours, and the coating film retention time is extremely short compared to the coating material of the present invention in Test Example 1. In addition, the copolymer lacking component (A) in Comparative Example (7) has uneven dissolution rate in the coating film depending on the location and pores are formed on the surface, but the coating material of the present invention has a uniform dissolution rate. , the surface condition is always uniform.

Further, in the copolymers of Comparative Examples (8) and (9) lacking the component (B), the elution rate of the coating film changes with the passage of time, but in the coating material of the present invention, it is constant.

Test Example 3 Polymer Nα9. which had a high elution amount in Test Example 1. Polymers Nα2 and Nα7, which had a medium elution amount, and polymer Nα10, which had a low elution amount, were selected and 5 c + IIX 10 cm
It was applied to a stainless steel test plate and dried to obtain a test piece with a coating thickness of about 1000 μm. This test piece was immersed in a freshwater cooling water tank for factory equipment for one month, and the state of adhesion of algae was observed. For comparison, a similar test was conducted on polymethyl methacrylate.

Table 5 shows the area of the part where algae adhered to the coating film as a percentage.

From the above results, it can be seen that the coating agent of the present invention has excellent antifouling effects in fresh water.

Table 5 Test Example 4 Polymer Nα9, which had a high elution amount in Test Example 2, Polymer Null, which had a medium elution amount, and Polymer No. 10, which had a low elution amount, were tested in advance for water resistance and corrosion resistance. 10 coated with tar epoxy paint (JIS K 5664 type), which is used as an excellent paint resin.
cm x 20cm mild steel plate (JIS G 3370)
It was coated on top and dried to obtain a test piece with a coating thickness of about 1000 μm. This test piece was immersed in the sea in front of the water intake of the power plant for a month, and the state of adhesion of shellfish and algae was observed. For comparison, a test piece coated with only tar epoxy resin paint was also observed in the same manner.

Table 6 shows the area of areas where algae and shellfish were attached in percentages.

The above results demonstrate that the coating material of the present invention exhibits excellent antifouling effects even in seawater.

Table 6

[Brief explanation of the drawing]

Fig. 1 is a front view of the test plate in Test Example 1, Fig. 2 is a perspective view of the fixed frame, Fig. 3 is a perspective view of the coating film dissolution test device,
FIG. 4 and FIG. 5 are graphs showing the elution state of the coating film in the comparative example. Agent Patent Attorney Sei Yanagihara Figure 1 Figure 2 Figure 3 Figure 4 Figure 8 Iron c0)

Claims (7)

[Claims] (1) (A) Monomers 5 to 75 represented by general formula (1)
Highlight %, 1 CH2==CC00(CH2mO)nR2””・(1)
(In the formula, R1 is H, CH3 or CH2CC00(Cl12m0)n R2, R'' is H or a hydrocarbon group having 1 to 28 carbon atoms, m is an integer of 2 to 4,
n is 1-200. ) (B) Polymerizable unsaturated carboxylic acid or its salt 3-55
Weight%, and (C): 15 to 80% by weight of hydrophobic polymerizable unsaturated monomer
A coating agent for materials that come into contact with water, characterized in that it contains a copolymer of , . (2) Component (A) is 10-70% by weight, component (B) is 5-50% by weight, and component (C) is 20-75% by weight.
The coating material according to claim 1. (3) R'' is a hydrogen atom, a methyl group, an ethyl group, an allyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a tert-butyl group, an amyl group, an isoamyl group,
hexyl group, heptyl group, 2-ethylhexyl group, octyl group, nonyl group, decyl group, undecyl group, lauryl group, tridecyl group, myristyl group, cetyl group, isocetyl group, stearyl group, instearyl group, oleyl group,
Octyldodecyl group, behenyl group, decyltetradecyl group, benzyl group, cresyl group, butylphenyl group, dibutylphenyl group, octylphenyl group, nonylphenyl group, lauryl phenyl group, dioctylphenyl group, dinonylphenyl group, or styrenated group The coating material according to claim 1 or 2, which is a phenyl group. (4) The coating material according to any one of claims 1 to 3, wherein Cm H2m O is an oxyethylene group, an oxypropylene group, an oxybutylene group, or an oxytetramethylene group. (5) Claim 1, wherein component (A) is an ethylene oxide, propylene oxide, butylene oxide or tetrahydrofuran adduct of acrylic acid, methacrylic acid or itaconic acid, or an alkyl ether, alkenyl ether or alkylphenyl ether thereof. The coating material according to any one of items 1 to 4. (6) Component (B) is maleic acid, fumaric acid, itaconic acid, an alkyl or alkenyl monoester thereof,
Acrylic acid, methacrylic acid, crotonic acid, or their lithium salt, sodium salt, potassium salt, ammonium salt, alkylamine salt having 1 to 4 carbon atoms, monoethanolamine salt, jetanolamine salt, or triethanolamine salt. The coating material according to any one of claims 1 to 5 η. (7) Component (C) is methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate-1, amyl (meth)acrylate
Acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate-1-, octyl (meth)acrylate-1-, nonyl (meth)acrylate-1, decyl (meth)acrylate, dodecyl (meth)acrylate, tetradecyl (meth)acrylate ) Acrylate, hexadecyl (meth)
Acrylate, octadecyl (meth)acrylate, oleyl (meth)acrylate, cyclohexyl (meth)acrylate
Acryle-1~, vinyl acetate, styrene, α-methylstyrene, acrylonitrile, vinyl chloride, butadiene,
or chloroprene, the coating material according to any one of claims 1 to 6.