JP2981120B2 - Rubber composition for preventing adhesion of underwater organisms and structure thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rubber composition for preventing underwater organisms from adhering to rubber or resin members of underwater structures, ships and the like.

[0002]

2. Description of the Related Art At present, an antifouling rubber which can be thickened as a material for preventing the adhesion of underwater organisms, and whose thickness can be adjusted, and which has a longer life than paint, is used as a rubber material for ships or underwater. Used for structures. As the component having the antifouling performance, the one using organotin such as tributyltin (TBT) and tripropyltin (TPT) has the highest effect,
The other components were significantly inferior in performance and could not withstand use.
However, since organotin pollutes seawater and freshwater and eventually affects the human body, it is difficult to use antifouling materials such as structures and members containing organotin in water.
It is in the direction of total ban. Therefore, the present inventors have developed a composition containing rubber and a 3-isothiazolone derivative as a non-tin-based antifouling agent that is less likely to contaminate water and that can prevent the adhesion of aquatic organisms.

[0003]

In particular, a composition using a 3-isothiazolone derivative having a halogen as a substituent has a high antifouling effect. However, when a 3-isothiazolone derivative having halogen as a substituent is used,
When the rubber is vulcanized for a long time under high temperature, which is the vulcanization condition, this derivative is thermally decomposed, and the active ingredient remaining in the rubber after vulcanization decreases in view of the anti-adhesion property of aquatic organisms. When the antifouling agent is thermally decomposed, it generates a hydrogen halide gas, which causes corrosion of a mold, a metal reinforcing material, and the like. When the hydrogen halide gas accumulates in the rubber, blisters and blisters are generated. There is such a problem. The present invention solves at least one of the above-mentioned problems.

[0004]

SUMMARY OF THE INVENTION The present inventors have found that when a rubber contains a 3-isothiazolone derivative having a halogen as a substituent and an acid acceptor, the adhesion of organisms in water can be prevented even when processed at high temperatures. The inventors have found that a composition for antifouling of aquatic organisms having a long performance life can be obtained, and the present invention has been accomplished.

That is, the present invention relates to (1) 100 parts by weight of rubber and (2) 0.5 to 0.5% of magnesium oxide as an acid acceptor.
30 parts by weight or lead red or pentaerythritol 2
To 20 parts by weight, and equation (1)

[0006]

Embedded image

(Wherein at least one of X ¹ and X ² is halogen, and the other is hydrogen, halogen, or a linear or branched alkyl group having 1 to 4 carbon atoms;
Y is a straight-chain or branched-chain alkyl group having 1 to 14 carbon atoms having no substituent, and halogen or carbon as a substituent.
It has a lower alkyl group having 1 to 3 carbon atoms or is an unsubstituted aralkyl group having 1 to 9 carbon atoms or a phenoxy group, a hydroxy group, a trihalomethyl group, a halogen, a 1 to 1 carbon atom as a substituent . It has 4 lower alkyl groups or lower alkoxy groups having 1 to 3 carbon atoms , or is an unsubstituted aryl group having 6 to 9 carbon atoms. )

Hereinafter, the present invention will be described in detail. The rubber used in the present invention is not particularly limited as long as it shows weather resistance and seawater resistance after vulcanization. For example, natural rubber (N
R), isoprene rubber (IR), styrene-butadiene rubber (SBR), ethylene-propylene rubber (EP
M), ethylene-propylene-diene terpolymer rubber (EPDM), isobutylene isoprene rubber (II
R), brominated isobutylene isoprene rubber (Br-II)
R), chlorinated isobutylene isoprene rubber (Cl-II)
R), chloroprene rubber (CR), chlorosulfonated polyethylene (CSM), nitrile rubber (NBR) and the like. Particularly, chloroprene rubber (CR), natural rubber (NR), brominated isobutylene isoprene rubber (Br-)
IIR), nitrile rubber (NBR), chlorosulfonated polyethylene (CSM) and the like are preferred.

The rubber used in the rubber composition of the present invention preferably has a number average molecular weight of 50,000 to 1,000,000.

In addition, when a resin is used in place of the rubber used in the present invention and a long-term exposure to a high temperature of 100 ° C. or more is required during the processing step, the compounding of the acid acceptor is effective.

In the present invention, the compound used for preventing aquatic organisms from adhering is represented by the formula (1)

Embedded image Is a 3-isothiazolone derivative represented by the formula:

In the formula, at least one of X ¹ and X ² is halogen, and the other is hydrogen, halogen, or a linear or branched alkyl group having 1 to 4 carbon atoms. Y
Is a linear or branched unsubstituted carbon atom having 1 carbon atom
To 14 alkyl groups, halogen or lower alkyl having 1 to 3 carbon atoms as a substituent, or unsubstituted aralkyl group having 1 to 9 carbon atoms, or phenoxy, hydroxy, trihalo as a substituent Methyl group,
It is a halogen, a lower alkyl group having 1 to 4 carbon atoms or a lower alkoxy group having 1 to 3 carbon atoms, or an unsubstituted aryl group having 1 to 9 carbon atoms. However, when the compound has a substituent containing a carbon atom, the number of carbon atoms in the aralkyl group and the aryl group is defined by the number including the carbon atom in the substituent.

Specific examples of halogen of X ¹ include chloro, bromo, iodo and the like. Specific examples of the halogen of X ² include chloro, bromo, iodo, chloromethyl, chloropropyl, bromomethyl, bromoethyl, bromopropyl and the like. Specific examples of Y include methyl, ethyl, propyl, isopropyl, butyl, hexyl, octyl, decyl, pentadecyl, octadecyl,
Cyclopropyl, cyclohexyl, benzyl, 3,4-
Dichlorobenzyl, 4-methoxybenzyl, 4-chlorobenzyl, 3,4-dichlorophenyl, hydroxymethyl, chloromethyl, chloropropyl, diethylaminoethyl, cyanoethyl, carbomethoxyethyl, ethoxyethyl, 2-methoxy-1-bromomethyl, 3, 3,5
-Trimethylcyclohexyl, phenoxyethyl, p-
Chloroanilinomethyl, phenylcarbamoxymethyl,
Allyl, propynyl, vinyl, carboxyethyl, 1-
Isothiazolonylethyl, 1,2,2-trichlorovinyl and the like.

Among them, X ¹ and X ² are preferably Cl, and Y is preferably an unsubstituted aralkyl or aryl group having 1 to 9 carbon atoms, particularly C ₈ H ₁₇ . Such 3-
Examples of the isothiazolone derivative include 4,5-dichloro-2-n-octylisothiazolin-3-one, which is available from Rohm and Haas. Further, such a 3-isothiazolone derivative does not have toxicity that pollutes the surrounding environment. For example,
4,5-dichloro-2-n-octylisothiazoline-
The LD ₅₀ of the 3-one is 1700 mg / kg (male rats) and 2800 mg / kg (female rats).

The content of the 3-isothiazolone derivative is 3 to 80 parts by weight based on 100 parts by weight of the rubber.
In particular, it is preferably from 5 to 55 parts by weight. Content is
If the amount is less than 3 parts by weight, sufficient antifouling property cannot be obtained.
On the other hand, if it exceeds 80 parts by weight, the crosslinking of the rubber is hindered and the network structure of the molecule becomes rough. Therefore, the antifouling property is not maintained.

Examples of the acid acceptor used in the present invention include magnesium oxide (MgO), lead red (Pb ₃ O ₄ ), and pentaerythritol. When magnesium oxide is used as the acid acceptor, 0.5 to 30 parts by weight, especially 0.1 to 30 parts by weight, per 100 parts by weight of rubber, depending on the amount of the antifouling agent.
It is preferably 5 to 6 parts by weight. If the amount of magnesium oxide is less than 0.5 part by weight, the effect of suppressing the thermal decomposition of the 3-isothiazolone derivative is insufficient, and if it exceeds 30 parts by weight, the processing performance of the rubber composition may be impaired. When lead acid (Pb ₃ O ₄ ) is used as the acid acceptor, 2 to 100 parts by weight of rubber is used depending on the amount of the antifouling agent.
30 parts by weight, especially 2 to 10 parts by weight. Lead Tan (Pb ₃
If the amount of O ₄ ) is less than 2 parts by weight, the effect of suppressing the thermal decomposition of the 3-isothiazolone derivative is insufficient, and if it exceeds 30 parts by weight, the processing performance of the rubber composition may be impaired. When pentaerythritol is used as the acid acceptor, the amount is 2 to 30 parts by weight, particularly 2 to 10 parts by weight, based on 100 parts by weight of the rubber, depending on the amount of the antifouling agent. If the amount of pentaerythritol is less than 2 parts by weight,
The effect of suppressing the thermal decomposition of the isothiazolone derivative is insufficient, and if it exceeds 30 parts by weight, the processing performance of the rubber composition may be impaired.

When a rubber containing a halogen such as chloroprene rubber (CR), chlorosulfonated polyethylene, or chlorinated polyethylene is used as the rubber component, the above-mentioned magnesium oxide, lead red, and pentaerythritol are preferably used as the acid acceptor. The appropriate amounts are as follows.
When magnesium oxide is used as the acid acceptor, it is added to 100 parts by weight of rubber according to the amount of the antifouling agent.
It is preferably 5 to 30 parts by weight, particularly preferably 2.5 to 6 parts by weight. When lead acid (Pb ₃ O ₄ ) is used as the acid acceptor, the amount is 4 to 30 parts by weight, particularly 4 to 10 parts by weight, based on 100 parts by weight of the rubber, depending on the compounding amount of the antifouling agent. Is preferred. When pentaerythritol is used as the acid acceptor, it is preferably 4 to 30 parts by weight, particularly preferably 4 to 10 parts by weight, based on 100 parts by weight of the rubber, depending on the compounding amount of the antifouling agent.

The rubber used in the present invention may contain a vulcanization accelerator, a vulcanizing agent, a vulcanization retarder, an antioxidant and the like. Specific examples of the vulcanization accelerator include tetramethylthiuram monosulfide (TS), dibenzothiazyl disulfide (DM), ZnO, MgO, stearic acid, N-cyclohexyl-2-benzothiazylsulfenamide (CZ), Tetramethylthiuram disulfide (TT), 2-mercaptoimidazoline (Na22)
And the like. The addition amount of the vulcanization accelerator is preferably 0.1 to 10 parts by weight based on 100 parts by weight of rubber.

Specific examples of the vulcanizing agent include sulfur, 4,4-
Dithiomorpholine (R), ZnO, MgO, PbO,
Pb ₃ O _{4 and the} like. The amount of vulcanizing agent added is
It is preferably 0.1 to 10 parts by weight based on 00 parts by weight.

Specific examples of the vulcanization retarder include N-cyclohexylthiophthalimide (PVI).
The amount of the vulcanization retarder is based on 100 parts by weight of rubber.
It is preferably 0.1 to 5 parts by weight.

Specific examples of the antioxidant include N-phenyl-N '-(isopropyl-p-phenylenediamine).
(3C), N-phenyl-N '-(1,3-dimethylbutyl-p-phenylenediamine) (6C), octylated diphenylamine (OD3), poly (2,2,4-trimethyl-1,2-di) Hydroquinoline) (RD), 2-
And mercaptobenzimidazoline (MB).
The amount of the antioxidant added is based on 100 parts by weight of rubber.
It is preferably 0.1 to 10 parts by weight.

In the rubber composition of the present invention, in addition to the above-mentioned components, fillers such as carbon, calcium carbonate, silica, talc and clay, coloring agents such as disazo red and disazo yellow, DOA, DBP, TCP and the like Plasticizers, aroma-based, naphthene-based, paraffin-based softeners and the like.

(Method for Producing Rubber Composition) The method for producing the rubber composition of the present invention is not particularly limited. For example, 100 parts by weight of the above rubber and 3-isothiazolone derivatives 3 to
It is obtained by adding and kneading 80 parts by weight and, if necessary, other additives. Further, a composition to which a vulcanizing agent is added can be produced.

(Production method of cured product) The production method of the cured product of the rubber composition of the present invention is not particularly limited. For example, in the case of chloroprene rubber (CR) or natural rubber (NR), sulfur or ZnO, MgO, Pb ₃ O ₄ or the like is used as a vulcanizing agent at a temperature of 100 ° C to 180 ° C,
At a high temperature of 50 ° C. and a pressure of 4 kgf / cm ² or more, 10
It is obtained by reacting for minutes to 24 hours.

The obtained rubber composition or a cured product thereof is appropriately molded, and the rubber composition for preventing underwater organisms from adhering can be used as an underwater rubber member or underwater structure.

Here, the underwater organisms are organisms that adhere to underwater parts such as ships, buoys, and artificial structures at the bottom of the water, and to parts that may be temporarily exposed to the sea due to low tide. Includes living organisms (adherent organisms). Specific examples include underwater animals such as barnacles, bryozoans, and serpula, and underwater plants such as seaweeds.

The underwater member using the rubber composition containing the 3-isothiazolone derivative of the present invention for preventing the adhesion of aquatic organisms or a cured product thereof includes a member used on the bottom of a ship, a ship side, a barge, a pier, Rubber buoys, fenders, marine hoses, airbags for floating and sinking ikes, and the like used for floating parts are used. These underwater members can be produced, for example, by using the rubber composition itself of the present invention, or by bonding the composition to a required portion of the underwater member.

The underwater structure using the rubber composition containing the 3-isothiazolone derivative of the present invention for preventing the adhesion of underwater organisms or a cured product thereof is a surface material of a submarine cable, a facility installed on the seabed. Containers that are fixed on the seabed such as a surface material, a quay, an oil mining rig, or artificially store seawater or freshwater, such as Ikes, and the like can be given.

The rubber composition containing the 3-isothiazolone derivative of the present invention for preventing the adhesion of organisms in water and the cured product thereof can maintain the effect of preventing the adhesion of organisms in water for a long time. As a mechanism of action, a molded product (antifouling layer) or a vulcanized molded product (antifouling layer) of an antifouling rubber composition containing a 3-isothiazolone derivative which is a component having an antifouling effect used in the present invention is treated with seawater. When immersed in water, the antifouling component of the surface layer elutes into the sea. As a result, a concentration gradient of the antifouling component occurs in the antifouling layer. It is conceivable that the antifouling component inside the antifouling layer migrates to the surface due to this concentration gradient and elutes into seawater from the surface of the antifouling layer.

When the rubber composition containing the 3-isothiazolone derivative of the present invention for preventing the adhesion of living organisms in water is formed into an underwater member or an underwater structure, the preferable thickness of the antifouling layer is 1
mm or more, particularly preferably 3 mm or more. 1mm
If it is less than 3, long-term release of the antifouling component cannot be expected, so that it is not suitable for practical use. If the thickness is 1 mm or more, the antifouling effect is effective for a long period of time, and it is considered that the 3-isothiazolone derivative as the antifouling component is sequentially transferred from the inside to the outside of the cured product of the rubber composition.

Further, the rubber composition of the present invention for preventing adhesion of underwater organisms is suitable for producing a structure having a thickness of 50 mm or more, particularly 100 mm or more. As described above, when manufacturing a thick structure, vulcanization is performed at a high temperature for a long time in order to vulcanize to the center of the structure. Even in such a case, when the composition of the present invention is used, the obtained structure does not have the antifouling component decomposed by heat during vulcanization or the like.
Therefore, antifouling performance can be maintained for a long time.
Furthermore, in the composition of the present invention, if the vulcanization at a high temperature for a long time, the acid acceptor reacts with chlorine in the antifouling component, which causes the generation of hydrogen chloride gas, so that no hydrogen chloride gas is generated. Further, since no hydrogen chloride gas is generated, corrosion of a mold, a metal reinforcing material, and the like does not occur. In addition, no blistering or blistering of the rubber, which is caused by accumulation of the generated hydrogen chloride gas in the rubber, occurs.

[0032]

The present invention will be described below in detail with reference to examples.

Examples 1 to 4 and Comparative Examples 1 to 8 (1) Polymers having the following compounding ratios were prepared. To the polymer at the compounding ratio in Table 1 below, various components were added at the compounding ratio in Table 1, and the mixture was kneaded for 4 to 6 minutes with a laboratory internal mixer, and the rubber composition of the present invention was cured under the vulcanization conditions shown in Table 1. Manufactured. About the obtained rubber composition, rubber physical properties and antifouling performance were measured. The measurement method and evaluation criteria are as follows (2)
And (3). Table 1 shows the results. Comparative Examples 1 to 8
The rubber properties and antifouling performance of the composition obtained in the same manner as in Example 1 were measured at the compounding ratio shown in Table 1 below. The measurement methods and evaluation criteria are shown in (2) and (3) below. Table 1 shows the results.

(2) Vulcanization performance under each vulcanization condition The composition obtained in (1) was vulcanized at 150 ° C. for 2 hours.
Vulcanization was performed at 50 ° C. for 3 hours and at 150 ° C. for 6 hours, and the state of vulcanization was evaluated. Evaluation criteria: ：: No rust on the mold and no blister on the rubber surface. Δ: There is no rust on the mold, but small blisters are generated on a part of the rubber surface. X: Rust of the mold was generated and a large number of blisters were generated on the entire rubber surface. -: Not implemented

(3) Antifouling performance Each rubber composition was vulcanized for 30 hours by using a mold in the same manner as in the preparation of the test specimen for normal physical properties test in (2), and was cured for 30 hours.
A test piece of 0 × 300 × 100 mm was obtained. The test specimens were dropped from the sea surface at a depth of about 1 m from the sea surface of about 400 m from the shore of Uranahama Beach in Numazu City, Shizuoka Prefecture, and one year later,
The degree of slime adhered on the sheet and the amount of living organisms were measured and evaluated according to the criteria shown in Table 2 below. The organism attachment rate (%) was indicated by the ratio of the area of the portion of the sheet to which the organism attached to the total area of the sheet. Based on this, whether the composition can be used or not as a marine rubber member or underwater structure of the present invention, ○, ×,
^{-Evaluated with *} and-. Table 1 shows the results of the evaluation.

(4) Rubber Properties The rubber properties of the cured product obtained by vulcanizing at 150 ° C. for 30 hours were measured for tensile test, elongation, and hardness in accordance with JIS K6251, K6301. Evaluation was based on criteria. Evaluation criteria: ○: tensile strength of 120 kgf / cm ² or more, elongation of 300
% Or more, hardness of 40 to 60 measured by JIS-A type spring hardness tester. ×: Tensile strength less than 120 kgf / cm ² or elongation less than 300%, hardness less than 40 by JIS-A type spring hardness tester, or 60 or more. − ^* : Those that could not be vulcanized. Or those that could not be evaluated due to blister generation. -: Not implemented

[0037]

[Table 1]

[0038]

(Examples 5 and 6) Except that an antifouling agent was added to the polymers shown in Table 3 below, and the acid-accepting agent was changed to lead tin,
A composition was produced in the same manner as in Example 1, and the vulcanization performance was measured and evaluated. Further, 30 vulcanized at 150 ° C. for 30 hours.
Using a test piece of 0 × 300 × 100 mm, the antifouling performance was measured and evaluated, and further, JIS K6251, K6301.
Rubber properties were measured and evaluated in accordance with.

[0040]

[Table 2]

(Examples 7 and 8) A composition was prepared and vulcanized in the same manner as in Example 1 except that an antifouling agent was added to the polymers shown in Table 4 below, and pentaerythritol was used as an acid acceptor. The performance was measured and evaluated. Further, the antifouling performance was measured and evaluated with a 300 × 300 × 100 mm test piece cured at 150 ° C. for 30 hours.
Rubber properties were measured and evaluated according to K6301.

[0042]

[Table 3]

[0043]

The rubber composition containing the 3-isothiazolone derivative of the present invention and an acid acceptor for preventing the adhesion of aquatic organisms or a vulcanized product thereof, even if vulcanized or cured at high temperature, does not cause environmental pollution. It is possible to prevent the adhesion of underwater organisms that continuously release non-hazardous antifouling components for a long period of time, and to manufacture a product that maintains the antifouling performance of the antifouling agent. Further, since the antifouling effect can be maintained for a long time even when vulcanization is performed at a high temperature, a thick structure can be manufactured. The present invention has at least one of the effects of the above-described invention.

Continued on the front page (51) Int.Cl. ⁶ Identification code FI C09K 3/00 112 C07D 275/02 (C08K 5/00 5:47 5: 053) (C08K 13/02 5:47 3:22) (58 6) Surveyed field (Int. Cl. ⁶ , DB name) C08L 7/00-21/02 C08K 5/46-5/47 A01N 43/80 C09K 3/00 CA (STN)

Claims (5)

(57) [Claims] (1) 100 parts by weight of rubber; and (2) 0.5 to 30 parts by weight of magnesium oxide or 2 to 30 parts by weight of lead oxide or pentaerythritol as an acid acceptor.
And amount unit, (3) (1) ## STR1 ## (Wherein, X ¹ and X ² are at least one of halogen and the other is hydrogen, halogen, or a linear or branched alkyl group having 1 to 4 carbon atoms, and Y has a substituent. Straight or branched alkyl group having 1 to 14 carbon atoms, halogen or carbon as a substituent
Or having atom number 1-3 lower alkyl groups, or unsubstituted aralkyl group having 1 to 9 carbon atoms or a phenoxy group as a substituent, hydroxy group, a trihalomethyl group, a halogen, 1 to carbon atoms It has 4 lower alkyl groups or lower alkoxy groups having 1 to 3 carbon atoms , or is an unsubstituted aryl group having 6 to 9 carbon atoms. A 3-isothiazolone derivative represented by the formula (1): 3 to 80 parts by weight. 2. A rubber composition for preventing underwater organisms from adhering to the rubber composition according to claim 1, further comprising a vulcanizing agent. 3. The thickness of a cured product of the rubber composition is 1 mm
A cured product of the rubber composition for preventing adhesion of underwater organisms according to claim 2, which is the above. 4. An underwater rubber member comprising a cured product of the composition according to claim 2 or a cured product according to claim 3 used as a surface layer. 5. An underwater structure, wherein the cured product of the composition according to claim 2 or the cured product according to claim 3 is used for a surface layer.