KR20200116366A - Thixotropic Agent for thinner of shipping paint - Google Patents

Abstract

The present invention relates to a method of manufacturing a thixotropic amide solution which acts as a flow control agent in a thinner of ship paints. The present invention, in order to control the fluidity of a liquid solvent thinner, uses bentonite, silica, hydrogenated castor oil, and polyamide wax. The problem is that the present invention should be accompanied by a semi-processed product form using solvent and shear forces, and the failure to carefully control the temperature will cause defects in the finished coating-based system. The method for manufacturing the thixotropic amide solution comprises the following steps: mixing a monohydroxy alcohol-based mixture with toluene diisocyanate, and replacing the air in a reactor with nitrogen gas at normal pressure, followed by stirring a reaction product; conducting a reaction of contents at 40 to 60°C for 2 hours and 30 minutes, and then stirring a first polar aprotic solvent DMSO to generate the reaction product; after completely dissolving a lithium salt in the remaining secondary polar aprotic solvent DMSO, producing diamine and amide wax compounds at a temperature of 60 to 70°C; when the reaction product is completely dissolved, fixing the same 70 to 90°C, and slowly dropping the reaction product manufactured in advance for 1 hour to proceed with an urea binding reaction. The present invention relates to the method for manufacturing the thixotropic amide solution, which acts as the flow control agent in the thinner of ship paints, and content thereof, wherein it is possible to improve production efficiency, increase work efficiency, and brings resource recycling and production cost reducing effects by recycling thinners.

Description

Manufacturing method of flow control agent for thinner for ship paint {Thixotropic Agent for thinner of shipping paint}

The present invention relates to a method of preparing a thixotropic amide solution that acts as a flow control agent in a thinner of a marine paint containing a non-aqueous solvent and dissolved particles, and the manufacturing method comprises a monohydroxy alcohol-based mixture with an excess of toluene diol. Reaction with an isocyanate to produce a monoisocyanate by-product, followed by reaction with diamine and amide wax in a polar aprotic solvent in the presence of a lithium salt to produce a thixotropic amide solution. The flow control agent of the present invention is easier to manufacture and simple to use compared to the flow control agent including urethane in the past, and is particularly related to maintaining continuous flow control ability.

The present invention relates to a method for preparing an effective thixotropic amide solution containing urea urethane in a thinner of a marine paint containing a water-insoluble solvent and dissolved particles, and more particularly, to a method of preparing a monohydroxy alcohol-based compound The present invention relates to a method for producing a thixotropic amide solution that acts as a flow control agent by reacting with an isocyanate to produce a monoisocyanate by-product, and reacting with a diamine and an amide wax compound in a polar aprotic solvent in the presence of a lithium salt.

J2006199907 A

KR100254385 B1

KR1019900005402 B1

US4596866 B

US4870151 A

JP2001049232 A

KR20060114339

In a liquid paint system, in general, the rate at which solid particles settle in the fluid system can be expressed by Stoke's equation, which can be briefly described as follows.

V=2r 2 .g(ps-p)/ 9n

V: Settling velocity r: Radius of solid particles ps: Density of solid particles

p: fluid density n: fluid viscosity g: gravitational acceleration

In order to reduce the sedimentation rate, it can be solved by reducing the radius of the dispersed particles, decreasing the density of the fluid and the particles, or increasing the viscosity of the fluid.If you simply increase the viscosity to prevent the sedimentation of the particles, the viscosity during work In addition to the high workability is poor, there is a disadvantage that a smooth surface cannot be obtained due to poor smoothness after work.

In order to control the fluidity of the liquid solvent thinner, mainly organically modified bentonite, silica, hydrogenated castor oil, and polyamide wax were used. The problem with these materials is that they are mostly dry solids that must accompany the product form semi-finished using solvents and shear forces, and must be incorporated into the liquid coating system under careful temperature control. If the temperature is not carefully controlled in this way, microcrystals are formed in the finished coating system, which causes defects in the coating.

The general fluid maintains a constant viscosity, but the fluid into which the viscoelastic modifier is added has the property of a gel state when standing, and when an external stress, that is, a shear stress is applied, it changes from a gel state to a sol state. It has the property of reversible change of the gelatinous sol in which the viscosity is reduced to a lower level and the viscosity is restored by reducing the viscosity from the sol state to a gel state when external stress is removed again.

In the Korean Industrial Standard (KS M5001), this property is called thixotropy, and it is described as a reversible property of colloidal particles that become a gel when left standing and become sol when stirred when the temperature is constant.

Other solutions for flow control are disclosed in European Patent Application EP-A-0 198 519. According to him, the isocyanate reacts with the amine in the presence of the film-forming resin solution to produce elements that form acicular crystals in a very finely dispersed form. Such modified film-forming binders are commercially available as flow-control binders and anti-settling binders called "sag control agents". The problem with these products is that they always bind with the binder from which they are made, and there is no possibility of subsequent universal modification of the processed coating composition.

The depression control agent is added to paints, greases, printing inks, coatings, etc., so that the viscosity is appropriately lowered during operation, which improves the flow characteristics and suppresses the flow of fluid after operation, as well as sedimentation of solid particles during storage. It shows a property that prevents

European Patent No. EP-B-0 006 252 discloses a method of preparing a thixotropic agent that eliminates some of the above problems, and an isocyanate adduct is prepared by reacting with a polyamine in a polar aprotic solvent in the presence of a lithium salt. Urea urethanes are disclosed. However, the product thus prepared has two serious problems. First, these thixotropic agents are characterized in that they have an indeterminate structure due to their manufacturing method. Although monoisocyanate adducts are disclosed, in fact the actual product is not monoadducts, but a mixture of other adducts. According to the disclosed method, the diisocyanate is first reacted with a monoalcohol. By this method, although the desired NCO-functional monoadduct is partially produced, a non-NCO-functional deadduct is also produced, and subsequent reactions with polyamines in the presence of lithium chloride result in uncontrolled chain elongation of urea urethane and Polymerization urea is produced. These products are prone to precipitation and are very difficult to maintain in solution.

Another problem with the thixotropic agent prepared by this method can be seen from the fact that only monoisocyanate adducts having the same structure always react with diamines.

This leads, first of all, to limited compatibility in the used coating system, which is evident in the gel structure or some haze, and then to lower rheological effectiveness.

Similarly, in U.S. Patent No. 4,314,924, diisocyanate, monoalcohol, and diamine were reacted to prepare a urea-urethane solution, which produced a product in which only diamine reacted to the diisocyanate molecule, thereby generating particles during storage alone, and in paint. When applied, it is difficult to obtain a transparent paint because it does not show good solubility, and particles are generated during the storage of the paint, resulting in loss of thixotropic properties. In order to solve this problem, many studies have been conducted. Among them, in U.S. Patent No. 6,617,468, diisocyanate and monoalcohol are first reacted to remove unreacted diisocyanate under high-temperature vacuum conditions, thereby generating compounds produced by reacting only diamine with diisocyanate. A study was conducted to minimize However, it is believed that there will be difficulties in the manufacturing process to be applied to the production site.

In order to solve the above problems, an object of the present invention is to provide a method for producing a flow control agent by producing a monoisocyanate by-product and reacting with a diamine and an amide wax compound in a polar aprotic solvent in the presence of a lithium salt.

The present invention relates to a method of preparing a thixotropic amide solution that acts as a flow control agent in a thinner of a marine paint containing a non-aqueous solvent and dissolved particles, and the manufacturing method comprises a monohydroxy alcohol-based mixture with an excess of toluene diol. Reaction with an isocyanate to produce a monoisocyanate by-product, followed by reaction with diamine and amide wax in a polar aprotic solvent in the presence of a lithium salt to produce a thixotropic amide solution. The flow control agent of the present invention is easier to manufacture and simple to use compared to the flow control agent including urethane in the past, and is particularly related to maintaining continuous flow control ability.

The object of the present invention is to react a monohydroxy alcohol-based mixture with toluene diisocyanate to produce a monoisocyanate by-product, and react with a diamine and an amide wax compound in a polar aprotic solvent in the presence of a lithium salt to produce a thixotropic amide solution. It is achieved by the manufacturing method that makes.

Hereinafter, the present invention will be described in detail.

First, a monohydroxy alcohol-based mixture is mixed with toluene diisocyanate in a well-dried reactor, and air in the reactor is replaced with nitrogen gas at normal pressure, and the reaction product is stirred. The contents are reacted at 40-60° C. for 2 hours and 30 minutes, and then the first aprotic solvent dimethyl sulfoxide (hereinafter, DMSO) is slowly added to generate a reaction product. Next, the lithium salt is completely dissolved in the remaining secondary aprotic solvent DMSO, and then a diamine and an amide wax compound are produced at a temperature of 60-70°C.

When the reactant is completely dissolved, it is fixed at 70 to 90°C, and the reactant prepared first is slowly added dropwise for 1 hour to proceed with a urea binding reaction to prepare a thixotropic amide solution.

The monohydroxy alcohol-based mixture used as a raw material for the first reactant was (1) butoxytriethylene glycol, and the toluene diisocyanate was (2) 2,4-toluene diisocyanate.

In the second step, the polar aprotic solvent is DMSO. The diamine and amide wax compounds are (3) 1,3-benzenedimethanamine and (4) octadecanamide.

The active ingredient of the final product synthesized in the above reaction is 45-55%.

[Example]

1st DMSO 2nd DMSO LiCl ⑴ ⑵ ⑶ ⑷ Sum Example 1 10 36 2 19 25 7 One 100 Example 2 11 35 3 18 25 5 3 100 Example 3 10 36 4 17 25 7.5 0.5 100 Example 4 12 34 3 18 25 6 2 100

The monohydroxy alcohol-based mixture is mixed with toluene diisocyanate to replace air in the reactor with nitrogen gas at normal pressure, and the reaction product is stirred. The contents are

After reacting at 40~60℃ for 2 hours and 30 minutes, the first polar aprotic solvent DMSO is stirred to form a mixture.

Next, the lithium salt is completely dissolved in the remaining secondary polar aprotic solvent DMSO, and then a diamine and an amide wax compound are produced at a temperature of 60-70°C. When the reactant is completely dissolved, it is fixed at 70 to 90°C, and the first reactant is slowly added dropwise for 1 hour to proceed with urea binding reaction to prepare a thixotropic amide solution.

[Comparative Example]

In the same manner as in the above examples, the monohydroxy alcohol-based mixture is (1) butoxytriethylene glycol, and the toluene diisocyanate is (2) 2,4-toluene diisocyanate.

In the second step, the polar aprotic solvent is DMSO. The diamine and amide wax compounds were used as raw materials for (3) 1,3-benzenedimethanamine and (4) octadecanamide reactants.

1st DMSO 2nd DMSO LiCl ⑴ ⑵ ⑶ ⑷ Sum Comparative Example 1 0 36 One 30 25 7 One 100 Comparative Example 2 10 36 One 20 25 8 0 100 Comparative Example 3 10 36 One 20 25 0 8 100 Comparative Example 4 10 36 0 19 25 8 2 100

In Comparative Example 1, the reaction was carried out using DMSO only in the second phase, but there was a large loss of the active ingredient of the reactant, and in Comparative Example 2, the reaction proceeded without using octadecanamide, but the flowability was very poor. In Comparative Example 3, the reaction was performed without using 1,3-benzenedimethanamine, but the flow and storage stability tended to be poor, and the reaction was performed without LiCl, but the storage stability of the reaction product was poor.

[Method of measuring flowability of thinner for ship paint]

After preparing the flow control agent of the above Examples and Comparative Examples, the physical properties were tested as follows.

In a PET round transparent container (50mm x 110mm), weigh 190g of thinner for ship paint and 10g of flow control agent, close the lid, and proceed as follows.

(1) Vortex mixer 1,000rpm, stirred for 10 seconds and then allowed to stand.

(2) After 1 minute, turn the container upside down and observe the gel-like flow of the mixture.

(3) After leaving for 24 hours, repeat the thinner mixture in the order of (1) to (3) for 7 days.

The gel-shaped flow state was tested in 1-10 steps.

1=weak. 10= excellent

mixture Gel flow state Company B (Europe) 9 Example 1 10 Example 2 9 Example 3 9 Example 4 10 Comparative Example 1 One Comparative Example 2 2 Comparative Example 3 One Comparative Example 4 2

In the case of the mixture of Company A (Europe) and Examples 1 to 4, the gel-like flow state was 9 to 10 excellent, and Comparative Examples 1 to 4 showed low results.

It is related to the production method and content of the thixotropic amide solution, which acts as a flow control agent in the thinner of marine paints, and can bring the effect of improving production efficiency, increasing work efficiency, recycling resources and reducing production cost by recycling thinners.

Claims (5)

A manufacturing method in which a monohydroxy alcohol-based 20-30% mixture is reacted with 10-30% of toluene diisocyanate in 1-20% DMSO of a primary polar aprotic solvent to produce a monoisocyanate by-product. A method of producing a thixotropic amide solution by reacting a diamine 5-10% and an amide wax 0.5-5% compound in a secondary polar aprotic solvent DMSO 20-50% in the presence of 1-5% lithium salt The method according to claim 2, wherein the diamine and amide wax compound are a compound of octadecanamide selected from 1,3-benzenedimethanamine. The method of claim 1, wherein the reaction to produce a monoisocyanate by-product is carried out at 40 to 60° C. for 2 hours and 30 minutes. The method of claim 2, wherein the thixotropic amide solution is carried out at 70 to 90°C for 1 hour and 30 minutes.