JPS5938264A - Antifouling paint - Google Patents

Abstract

PURPOSE:To provide an antifouling paint with excellent self-abrasive properties and reduced frictional resistance, free of adherent slime, by incorporating a specific organotin polymer. CONSTITUTION:An organotin polymer of formula I {wherein R is 6-20C straight-chain or branched alkyl (phenyl); R' is H, 1-4C lower alkyl; R'' is H, 1-4C lower alkyl, phenyl, carboxyl (ester); R''' is 3'6C lower alkyl, phenyl, benzyl, allyl; the structural unit -[M]- comprises one or more unsatd. monomers capable of copolymerizing with formula II, and the unit -[M]- and formula IIIare randomly arranged in the molecule; (a+b) is 10-1000; b/(a+b) is 0.5 or above} and, if necessary, cuprous oxide, chlorinated rubber, etc. are incorporated to obtain the titled paint.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improved antifouling coating using a polymer or copolymer of an unsaturated organotin compound as an antifouling agent and resin.

Marine organisms adhere to the lower part of the ship's surface, which increases the frictional resistance of the ship's hull, resulting in increased fuel costs and a decrease in ship speed. To prevent this, antifouling paint is applied to the bottom of ships, but the conventionally used rosin antifouling paint has the following two main disadvantages.

(1) Since the highly toxic antifouling agent is contained in the paint as it is, workers are likely to get injured during the painting process.

(2) As the surface roughness of the coating film itself gradually increases, the resistance due to the roughness increases, which in turn leads to an increase in fuel costs and a decrease in ship speed.

On the other hand, conventional antifouling agents in ship bottom antifouling paints include tributyltin compounds such as bis(tri-n-butyltin) oxide and bis(tri-n-butyltin) mesodibromosuccinate, triphenyltin hydroxide, Triphenyltin compounds such as triphenyltin chloride are used in large quantities in paints in the form of cross-dispersion. however,
These organic tin compounds generally have strong acute toxicity such as dermal toxicity and oral toxicity, and when handling antifouling paints containing them, protective masks and gloves are required. In addition, there are many cases in which paint causes damage such as inflammation when applied to the skin or mucous membranes. Particularly when painting large ships, the work is extremely difficult because a large amount of paint is used.

Further, as the antifouling agent dissolves, a residual coating film called a skeleton layer increases the frictional resistance on the coating surface.

A self-polishing antifouling paint that solves the above-mentioned disadvantages of conventional antifouling paints is mainly used on large tankers, ferries, and the like. In general, self-polishing antifouling paints are those made by reacting an organic tin compound with an antifouling effect with a polymer (hereinafter referred to as -j51.-f organotin polymer) as an antifouling agent and resin. Used, special public service 1976-21
The invention of No. 426 is a typical example. It is well known that such organotin polymers have an antifouling effect and are significantly less toxic to the human body, and such a report is also reported in Shipbuilding Technology Magazine, 1979, No. 6, p. 50. be.

The organotin polymers currently used have the general formula: % formula %) (where Bl is a hydrogen atom or a lower alkyl group having 1 to 4 carbon atoms, R'' is a hydrogen atom, and 1 to 4 carbon atoms Polymers of unsaturated organotin compound monomers represented by lower alkyl groups, )-class alkyl groups, phenyl groups, benzyl groups, or allyl groups having a carbon atom, or other vinyl monomers copolymerizable therewith. The general formula (II) is 10 to 1000, and b/(a-4-b) is 0.15.
The average molecular weight is 50.
．． It is about 000. The antifouling effect of the antifouling paint containing the organic tin polymer represented by the general formula (1[) is achieved by the hydrolysis of the 1% tin polymer as shown in reaction formula (A). expressed.

Same as above.

In other words, when the paint coated as a film is immersed in seawater, the hydrogen ion concentration of the seawater is 8.0 to 8.3, which is slightly alkaline. Organotin 1 bound as a salt of a carboxylic acid
(As shown in reaction formula (A), the Jj staining agent undergoes gradual hydrolysis and elutes free Ht, and further dissolves as a water-soluble polycarbonate sodium salt represented by general formula (II). Therefore, the antifouling coating surface is repeatedly renewed, and a new antifouling coating surface always appears, maintaining the antifouling effect.

Therefore, even though it has low toxicity when applied, the organic tin antifouling agent is eluted in seawater and exhibits an antifouling effect.

Generally, the total resistance (Rt) received from seawater at the bottom of a ship is expressed by the following formula.

Rt=Rw-1-Rf+Rr (wherein, Rw represents wave resistance, Rf represents frictional resistance, and R1 represents roughness resistance).

RW is an inherent property determined by the ship's shape and cannot be reduced by antifouling coatings. R2 and n, lma antifouling coating and Wi
j Resistance related to water, Rr mainly caused by the unevenness of the antifouling coating) y; RfG; J mainly due to the viscosity of seawater, both of which were reduced by improving the antifouling coating ++= It is possible.

The ratio of these sizes is 10-20% for Rw and 80-90% for Rf + Rr for large ships such as large μ and retankers.
In a ship weighing tens of thousands of tons, Rw is 20 to 30%, R,+R, is 70 to 80%, and R1 is much larger than Rr.

Due to the stone n++ shock that has passed twice so far,
Oil prices are high by 1t': 4. I regret that energy saving measures are being called for. Ij Sei￥? Also, fuel cost reduction vs. 94.
As a ship j''!'S (Ijj f'j Low weight due to improvement of paint: h: < 4!!, granulation and high antifouling performance are required, but conventional rosin yarn 1 (1j stain? A
Since the FI cost increases to 1++i, and the long-term antifouling effect is insufficient, it is not desirable from the viewpoint of energy saving effect. On the other hand, there are 4. l5jj fIj paints using ``IA#Uj polymers are monopoly (II) and (
Ill) as shown in Japanese Patent Application Laid-Open No. 53-5023.
As described in No. 6, because it gradually dissolves from the convex parts of the surface layer of the paint film, the surface of the paint film gradually becomes smooth as if it had been polished, and the surface roughness caused by uneven coating during painting becomes smaller. Data has been proposed to reduce roughness resistance (Rr) and reduce fuel costs.Because of these functions, antifouling paints using organic tin polymers are generally self-polishing type antifouling paints. Therefore, this self-polishing antifouling paint partially satisfies the requirements of the shipping industry.However, these self-polishing antifouling paints are only intended to reduce roughness resistance (Rr), and they also have a large frictional resistance (Rr). Currently, it is not possible to reduce Rf), and even in terms of antifouling effects, the presence of deposits called slime increases resistance, and further improvements are needed.

The major feature of the present invention is that while maintaining the advantage of self-polishing properties of current self-polishing antifouling paints, it further improves it to reduce frictional resistance (Rf') and eliminates slime and other deposits, thereby increasing the antifouling effect. This was resolved at the same time.

The present invention relates to the general formula (■): (wherein R is a linear or branched alkyl group or alkylphenyl group having 6 to 20 carbon atoms, preferably 6 to 12 carbon atoms. a straight-chain alkyl group or a branched alkyl group or an alkylphenyl group, more preferably a mono-alkyl group having 6 to 12 carbon atoms; R/ is a hydrogen atom or 1 to 12 carbon atoms;
4% lower alkyl having 4 carbon atoms, R11 is a hydrogen atom, a lower alkyl group having 1 to 4 carbon atoms, a lower alkyl group, a phenyl group, a benzyl group or an allyl group, a structural unit of 1,000 M+ and CtJLlbn(R"']3. +M+ represents acrylic acid or methacrylic acid and their esters, acrylic monomers such as acrylonitrile, styrenes such as styrene and vinyltoluene, and vinegar. Such as vinyl monomers, maleic anhydride and norph esters (1!
I(R'=OR10OOSn(R"')3 monoh1 and one or a combination of two or more unsaturated monomers copolymerizable, preferably acrylic acid, methacrylic acid, 2 -Hydroxyethyl methacrylate, diethylene glycol monoacrylate, acrylonitrile,
A combination of hydrophilic monomers such as maleic anhydride, the degree of polymerization of the monomer h1 represented by (a+b) is 10.
-1000, preferably 20-500, more preferably 60-350, more than the structure expressed by b/(a-1-b), preferably 0.25-0.6) This invention relates to an antifouling paint containing the following.

The organotin polymer used in the present invention can be produced by a known method as shown in Production Examples. That is, it is advantageous to use a solvent in the polymerization reaction, and the solvent is preferably one that dissolves the monomers and catalyst to be reacted. Various polymerization initiators are advantageously used, such as organic peroxides, diazo compounds such as azobisisobutyronitrile, and depending on the solvent, alkali metal persulfates.

In order to carry out the polymerization more effectively, an oxygen-free atmosphere is preferable, and the polymerization is carried out while blowing an inert gas such as nitrogen.

Advantageous polymerization methods for use in the present invention include, for example, dissolving all of the alkyl mercaptan and monomer in a solvent and then gradually adding a polymerization initiator dissolved in the solvent; It is synthesized by gradually dropping a solution of polymer and initiator into a solvent.

The major difference between the organotin polymer used in the present invention and the conventional organotin polymer is that the conventional organocopper polymer undergoes the process shown by reaction formula (A) by hydrolysis in seawater to produce polycarboxylic acid or its co-polymer. In contrast, the organic tin polymer used in the present invention has the general formula (■): (in the formula, (-M-1-, R , R', R'', R''', a
and b are the same as above), the polycarboxylic acid has an alkyl group or an alkylphenyl group as a lipophilic group at the end, so it is eluted by hydrolysis in seawater through the process shown by reaction formula (B). Alternatively, the sodium salt of its copolymer has a structure as a surfactant having a lipophilic group and a woody group in the same molecule, as shown in general formula (5)).

(In the general formula (Found), R1, R//Sa and b are the same as above.) As described above, the organotin polymer represented by the general formula (I) used in the present invention has the general formula (I This polymer has been improved so that it retains the advantage of self-polishing properties of the conventional organic tin polymer represented by [), while also having a surface-active effect.

That is, the concentration of the organotin polymer of the present invention after hydrolysis is 1
The results of measuring the surface tension and frictional resistance with water of a 100pp polymer aqueous solution in terms of torque reduction rate are shown in Table 1. Although the reason for this frictional resistance reduction effect has not yet been fully investigated, the resin This is thought to be because the surface tension of the seawater on the coating film surface decreases as the component becomes a surfactant and elutes, resulting in a smaller contact angle.

According to the section on the Toms effect on page 152 of the Chemical Engineering Handbook Revised KJ 4th edition, it is said that soap liquid has a frictional resistance reducing effect, and some insects that live on the surface of the water, such as the C. In the event of a crisis caused by a foreign enemy, some species release surfactants from within their bodies to lower resistance and increase speed.

These examples also suggest that surfactants have the effect of reducing frictional resistance.

The antifouling effect of the antifouling paint of the present invention is largely due to the organic tin compound that is freely eluted by hydrolysis. This is because, in addition to cleaning the surface, living things dislike surfactant liquids, which is a major difference from conventional organic tin polymers and is an improvement.

Since the polymerization method used in the present invention utilizes the known continuous transfer method of alkyl mercaptans, the molecular weight can be controlled freely, and the polydispersity coefficient is approximately 2.5 when measured by gel permeation chromatography. One of the features is that polymer design is much easier than in the conventional method using only a polymerization initiator because the following results are obtained.

When producing an antifouling paint containing the organic tin polymer of the present invention, it can be used alone or in combination with other antifouling agents, preferably in combination with cuprous oxide. Also chlorinated rubber,
It can also be used by mixing with acrylic resin, vinyl chloride resin, etc. Next, the present invention will be explained by showing production examples, working examples, and test examples. It is not limited to examples only.

Production Example 1 (n-octyl-5-(methyl methacrylate) 12"-
Butyltin methacrylate)) Production of 8-H) Methyl methacrylate 120.0 Benzoyl peroxide 12.1 Toluene 443.3886.6 a-1-b=2Q b/(a+b)=0.4 Stirrer, thermometer The above toluene was completely charged into a reaction flask equipped with a cooling condenser and a nitrogen gas inlet, and then heated to 80°C while stirring and blowing nitrogen gas.
The temperature was increased to ~85°C and maintained at that temperature until the end of the reaction. When the temperature rose to 80°C, the remaining entire solution was added dropwise over 2 hours and the reaction was allowed to proceed for an additional 5 hours. The heating residue of the reactant was 48.6%, and the reaction rate calculated from the theoretical value of 50% was 97.2%.

The molecular weight was determined by the fJ-i%E method, and the average molecular weight was approximately 4,300, which agreed well with the calculated value of 4,312. In addition, when the molecular resistance distribution was measured using gel permeation chromatography using #1'J, the polydispersity coefficient was very low at 1.4, and the molecular weight distribution was also narrow.

Production Example 2 (n-octyl-5-(methyl methacrylate) 64-(
Production of n-butyltin methacrylate) 3o-H) n-octyl mercaptan 11
．． 2I! d(n-)liptyltin methacrylate
1125.0 Methyl methacrylate)
640.0 Benzoyl peroxide
12.1 Toluene
1788.33576.6 a-)-b=94 1,/(a-1-b)=0.32 Synthesized in the same manner as in Production Example 1 using the above components. The reaction rate was 99%, and the molecular weight & mags, oo.

The polydispersity coefficient was 1.8.

Production Example 3 n-)butyltin methacrylate) 225
0.0 methyl methacrylate)
1!100.0 benzoyl peroxide
12.1 Toluene
5582.37164.6 a+1)=190 a/(a-1-b)=0, 52 Synthesized in the same manner as in Production Example 1 using the above components. The reaction rate was 98%, the molecular weight was approximately 35,000, and the polydispersity coefficient was 2.0.

Production example 4 (n-dodecyl-5-(acrylonitrile) 4□, -(
n-tributyltin methacrylate). . -Production of H)
n-dodecyl mercaptan 20.2
Part n-) Liptyltin methacrylate) 37
5[1,[l Acrylonitrile
2178.5 lauroyl peroxide
19.9 Toluene 5
968.4119375.8 a+b=511 bAa+ or 0.2 Using the above components, fi! ! It was synthesized in the same manner as in Preparation Example 1. The reaction rate was 97.4%, and the molecular weight was about 59,000.
The polydispersity coefficient was 2.3.

Production Example 5 (n-dodecyl-5-(methyl methacrylate) 60-(
octyl acrylate) -(n-tributyltinmethacrylate 1)
Route) Production of 30-H) n-dodecyl mercaptan
20.2 parts n-) lipyltin methacrylate) 1125. [l Methyl methacrylate
600.0 Octyl acrylate
36.8 lauroyl peroxide 20.0 toluene
1802.03604.0 a-)-b=9Q b/(a-1-'b)=0.33 In a reactor similar to Production Example 1, the above n-dodecyl mercaptan, n-tributyltin methacrylate, and methacrylic After completely charging methyl acrylate, octyl acrylate, and toluene, the mixture was heated to 80°C while stirring and blowing nitrogen gas.
The humidity was increased to 0.05 °C and the temperature was maintained until the end of the reaction.

When the temperature reached 80°C, 7 parts of lauroyl peroxide was added, and after reacting for 1 hour, 7 parts of lauroyl peroxide was further added, and after reacting for a further 2 hours, 6 parts of the crosspiece was added, and the reaction was continued for a further 5 hours. The reaction rate was 96%, the molecular weight was is, ooo, and the polydispersity coefficient was 1.5.

Production Example 6 n-octyl mercaptan 11.
2 parts methacrylic acid 172.0
Methyl methacrylate 420.0 Benzoyl peroxide 12.1 Bis(n-butyltin) oxide 596.
0 toluene 962.3
n-butanol 240. O
b/(a+b)=0.32 After charging 663 parts of the above toluene and the entire amount of n-butanol into a reaction apparatus similar to Production Example 1, the temperature was raised to 80 to 85 degrees while stirring and blowing nitrogen gas. The temperature is maintained until the end of the reaction. 1, each stage is 8000
When the reaction time was reached, a total solution of n-octyl mercaptan, methacrylic acid, methyl methacrylate, and benzoyl peroxide was added dropwise over 1 hour, followed by further reaction for 5 hours. After the polymerization reaction was completed, the remaining amount was added, the temperature was raised to 114°C, and the generated water was removed by reflux, and the reaction was terminated when no water came out. The reaction rate is 100
%, the molecular weight was 12,000, and the polymolecular f'& coefficient was 1.4.

Production Example 7 (n-octyl-8-(2-hydroxyethyl methacrylate))□. -(n-)butyltin medacrylate),
. -Production of H) n-octyl mercaptan
14.6m2-Hydroxyethyl methacrylate 130.0 Methacrylic intoxication
86.0 ammonium persulfate
0.37 bis(n-butyltin) oxide 298.0 methanol
230.0n-butano-j

115.0 dollars all
116.0989.97 a-)-b=20 b/(a+b)=0-5 The above methanol 180
After charging all i= of n-octyl mercaptan, 2-hydroxyethyl methacrylate and methacrylic acid, the mixture was heated at 35° while stirring and blowing nitrogen gas.
The temperature was raised to C and maintained at that temperature until the end of the reaction. When the temperature reached 35°C, a methanol solution of ammonium persulfate was added dropwise over 4 hours to complete the synthesis. The reaction rate is 10
It was 0%. 230 parts of this solid content was added to 1 part of n-butanol.
Bis(n-butyltin) oxide dissolved in 15 parts 298
The temperature was raised to 90°C. After 1 hour, the remaining dolol was added and the mixture was cooled. The water produced was removed with anhydrous magnesium sulfate. The molecular weight did not change to a constant value and could not be measured.

Production Example 8 (n-octadecyl-5-(methyl methacrylate)!5
'7-(TI-tributyltin methacrylate)30-
Production of H) n-octadecyl mercaptan
28.6 parts n-) Liptyltin methacrylate
1125.0 Methyl methacrylate
570.0 Benzoyl peroxide
12.1 Toluene
1735.7!1471.4 a+b=87 b/(a+b)=0.34 Synthesis was performed in the same manner as in Production Example 1 using the above components. The reaction rate was 97%, the molecular weight was approximately 18,000, and the polydispersity coefficient was 2.1.

Production Example 9 (Refinery of n-dodecyl-5-(styrene)2o-(methyl methacrylate)43-(n-triphenylfItac1 route)3o-H) n-dodecylmercaptan
11.21sn-) Riphenyltin methacrylate 1125.0 Methyl methacrylate 430.0 Styrene
208.0 Benzoyl peroxide 12.1 Toluene 1786.3
3572.6 a = 93 b/(a+b) = 0.32 Synthesis was performed in the same manner as in Production Example 1 using the above components. However, the reaction time was 16 hours. The reaction rate was 91% and the molecular weight could not be measured.

Comparative example n-) Lipchi methacrylate) 22
50.0 parts methyl methacrylate
1300.0 benzoyl peroxide
12.1 Toluene
3562.17124.1 Synthesized in the same manner as in Production Example 1 using the above components. The reaction rate was 99.8% and the molecular weight was 43,000.

Example (Ai!1llI combination) Cuprous oxide 35 parts talc
1゜Additive
6 xylene
1600 Produced by dispersing and mixing the above formulation.

Example (B combination) Titanium oxide 25 talc
1゜Additive
6 Xylene 2600 Test Example Antifouling Performance Test In the sea area under Wakayama Prefecture, the number of creatures wearing armor was investigated by hanging 1 meter below the sea surface for 24 months.

Judgment method 0: No biofouling 1: 〃 1-10% 2: /' 11-25% Ro: 〃 2
6-49% 4: // 50% or more S-slime adhesion The results are shown in Table 1.

Table 1 (Surface tension and friction resistance test) Surface tension and Frictional resistance was measured by torque reduction rate measurement.

Hydrolysis was carried out by the method shown below. That is, pH 9
, 0 sodium hydroxide solution was added with 100 parts of the powdered resin of the production example or comparative example, and the temperature was raised to 50°C. Then, when the pH is measured while stirring, the pH gradually changes.
(Hydrogenation necessary for hydrolysis is carried out in advance to prevent the pH from decreasing) IJum aqueous solution 1000
The area was gradually brought under control. The end of hydrolysis was defined as the point at which no powder was left in the aqueous solution and the solution was completely emulsified after the dropping was completed.

The surface tension of the above polymer aqueous solution with a concentration of 1 OOppm is determined by JT and J Engineering SK 33626.4.1-1.
Measured by 978.

FIG. 1 is a schematic explanatory diagram showing a method of measuring the torque reduction rate. In Figure 1, (1) is a drive motor, (2) is a torque converter, (3) is a photoelectric tachometer, (4) is a bearing, and (5) is a photoelectric tachometer.
) is the test cylinder, and (6) is the water tank.

To measure the torque reduction rate (%), the aqueous polymer solution with a concentration of iooppm was placed in a water tank (6), and the test cylinder (5) was rotated at a surface speed of 10 knots by the drive motor (1). The rotation shaft torque received by the cylinder (5) was measured using a dynamic strain measuring device and recorded using an oscilloscope recording device.

Table 2 As shown in Table 2, the organotin polymer of the present invention has a friction reducing ability after hydrolysis, whereas the comparative example, which is a conventional organotin polymer, has no friction reducing ability at all. I don't have it.

[Brief explanation of the drawing]

FIG. 1 is a schematic explanatory diagram of a torque reduction rate measuring device for evaluating the frictional resistance of an organic tin polymer used in the present invention. (Main symbols in the drawing) (1): Drive motor (2):) Luxury converter (5): Test cylinder Figure 1

Claims (1)

[Claims] 1 General formula (■): (wherein R is a linear or branched alkyl group or alkylphenyl group having 6 to 20 carbon atoms R
/ is a hydrogen atom or a lower alkyl group having 1 to 4 carbon atoms, R is a hydrogen atom, a lower alkyl group having a lower purple atom having 1 to 4 carbon atoms, a phenyl group, a benzyl group, or an allyl group , and the constituent unit M-) is OH
R" = OR〆OOOS n (R") It is based on one or more unsaturated monomers copolymerizable with 3, and the constituent units +M:3- and +aHR"-OR'% are random in the molecule. Array 000 to
S n (R”)3 and (a4-b) is 10 to 1000, b/(a+
b) is 0.15 or more).