KR100814004B1 - Method for manufacturing watersoluble amide wax - Google Patents

Abstract

A method for manufacturing water-soluble amide wax is provided to promote sagging control of paints, anti-settling during storage, and stability maintenance of viscosity of the paints for a stirring condition. A method for manufacturing water-soluble amide wax comprises the steps of: mixing primary diamine with 2-8 carbon atoms with relatively excessive dimer carboxylic acids, and dicarboxylic acid with 3-16 carbon atoms or monocarboxylic acid with 2-17 carbon atoms; compounding polyamide; forming salt by neutralizing the polyamide with a base; and manufacturing wax of a state that the polyamide is dispersed in water as a solvent.

Description

Method for Manufacturing Water Soluble Amide Wax

Korea Patent Registration 10-0309713-0000

Korea Patent Registration 10-0037627-0000

Korea Patent Registration 10-0254385-0000

The present invention relates to a process for preparing a water-soluble amide wax that acts as a Thixotropic Agent, in a fluid containing water-soluble suspensions or fine solid particles.

The general fluid maintains a constant viscosity, but the fluid in which the viscoelastic modifier is in a gel state when stationary, and when the external stress or shear stress is applied, the fluid changes from a gel state to a sol state, When the viscosity is lowered and the external stress is removed again, the gel can be reversibly changed from the sol state to the gel state and the viscosity can be recovered.

This property is called thixotropy, and the Korean Industrial Standard (KS M5001) states that it is a reversible property of a colloidal dispersion which becomes a sol phase when stirred at a constant temperature and a gel phase when left standing.

Viscoelasticity modifiers are added to paints, varnishes, printing inks, adhesives, laminates, enamels, etc. to reduce the viscosity during operation to improve flow characteristics, and to inhibit fluid flow after operation. It has the property of preventing sedimentation of solid particles during storage.

In liquid paint systems, the rate at which solid particles settle in a fluidic system can be expressed by Stoke's equation.

In order to reduce the settling speed, it can be solved by reducing the radius of the dispersed particles, by reducing the density difference between the fluid and the particles, or by increasing the viscosity of the fluid. It is not only poor workability due to high, there is a disadvantage that a smooth surface can not be obtained because of poor leveling (working).

The present invention relates to rheological agents applied to water-soluble metal paints, anticorrosive paints or paints containing high specific gravity pigments that require sedimentation prevention. Aluminum and mica pigments used in metal paints and pigments used in anticorrosive paints have a very large particle size. In addition, the specific gravity is also large, the pigment settling in the paint occurs very quickly. As is well known, oil-soluble amide waxes or polyethylene oxide waxes are used as antisettling agents in oil-soluble paints. However, most of these additives are not suitable for water-soluble paints.

Recently, studies on water-soluble paints are being actively conducted due to environmental problems, and clay- or silica-based silicas are recommended as inorganic sedimentation inhibitors. However, these inorganic additives cause gloss deterioration and are difficult to add at the final stage after paint production. In addition, since the state of the additives in the form of fine powder, the generation of dust in the paint production is very severe.

It is an object of the present invention to provide a method for producing a water-soluble amide wax for solving the above problems.

The object of the present invention is a primary diamine having 2 to 8 carbon atoms; A polyamide is synthesized as a mixture of a relatively dimer carboxylic acid or dimer acid and another dicarboxylic acid having 3 to 16 carbon atoms or a mono carboxylic acid having 2 to 17 carbon atoms, and neutralized with a base to neutralize the salt. It is achieved by the manufacturing method of the water-soluble amide wax characterized by manufacturing the wax in the state in which the polyamide was disperse | distributed to the water which is a solvent.

The dimer acid used in the present invention is obtained through dimerization reaction using unsaturated fatty acids. And dicarboxylic acids used together are succinic acid, adipic acid, azelaic acid, sebacic acid and the like. Monocarboxylic acids are 12-hydroxystearic acid, oleic acid, lauric acid, stearic acid and the like. The molar ratio of dimer acid in these mixtures is at least 60%. If more than 60% synthesized amide wax can be solubilized, it is effective as an additive.

Primary diamines used in the present invention are m-xylidenediamine, ethylenediamine, 4,4-diamino-diphenylmethane and the like.

The equivalent excess ratio of total carboxylic acid to primary diamine is 1.2 to 1.5. If less than 1.2, it is difficult to accept and the effect of performance is small. And when it is 1.5 or more, when applied to paint, the water resistance of paint coat falls.

The final acid value of the amide synthesized by the present invention is in the range of 40-100 mgKOH / g. The range of 50-90 is most suitable. Amide synthesis reactions are similar to those commonly used. It proceeds with a condensation reaction of water coming out at about 180 ° C. for about 5 hours. After cooling the synthesized amide to about 100 ℃ and then added an organic solvent to lower the viscosity, maintain the contents at 80 ~ 90 ℃ and put a small amount in the water dissolved neutralizing base. At this time, the reaction part should be maintained at about 50 ~ 70 ℃, it should be stirred to become a uniform phase. These neutralized amides generally form waxes after hours to a day. The solid content of the final composite is 15-30%.

The present invention will be described in more detail with reference to the following Examples.

Example 1

In a four-necked flask, dimer acid (0.63 mole) and azelaic acid (0.27 mole) were added to the reaction part, and the mixture was heated with stirring to 60 to 70 ° C. At this time, nitrogen was continuously injected from the beginning to the end of the reaction to prevent oxidation of the contents. When the contents were in a liquid state, hexamethylene diamine (0.65 mole) was added to the reaction part, the temperature of the contents was raised to 140 ° C. for 1 hour, and the temperature of the contents was further raised to 190 ° C. over 4 hours. The acid value and amine value were measured every hour, and when the amine value was 5 or less and the acid value was 65 or less, the reaction was terminated and the temperature of the contents was cooled to 100 ° C. Since propylene glycol monomethyl ether corresponding to 50% of the synthesized amide was added and the temperature of the contents was maintained at 80 ℃. The water in which 2-dimethylaminoethanol (0.35 mole) was dissolved was stirred, and a small amount of neutralized amide solution was added thereto. At this time, the content temperature was maintained at 60 ℃. Further stirred at 60 ° C. for 1 hour, cooled to room temperature and aged for 1 day. Polyamide solids in the synthetic product was about 20%.

Examples 2 to 6 and Comparative Examples 1 to 2 were synthesized in the same manner, and the raw materials and the property test results are shown in Tables 1 and 2.

Table 1. Amide Wax Synthesis

Raw material type Raw material name Example Comparative example One 2 3 4 5 6 One 2  Mountain Dimer acid 0.63 0.50 0.55 0.65 0.60 0.65 0.60 0.50 Azela Mountain 0.27 0.15 Succinic acid 0.19 0.25 12-hydroxystearic acid 0.10 Amine Hexamethylenediamine 0.65 0.60 0.40 0.65 0.20 0.45 m-xylidenediamine 0.30 0.42 Neutralizer (mole) 2-dimethylaminoethanol 0.35 0.40 0.36 0.43 0.45 0.37 0.78 0.15 Acid value of polyamide (mg KOH / g) 61 72 64 71 76 63 125 26

Table 2. Paint property test

Test Name Composition Example Comparative example One 2 3 4 5 6 One 2 Water Soluble Acrylic Resin ^{* 1} 44 44 44 44 44 44 44 44 Melamine resin ^{* 2} 10 10 10 10 10 10 10 10 Distilled water 34 34 34 34 34 34 34 34 Water Soluble Aluminum Paste ^{* 3} 10 10 10 10 10 10 10 10 Thixotropic agent 2 2 2 2 2 2 2 2 Paint property 1C 2C 3C 4C 5C 6C 9C 10C Thixo Index 2.64 1.80 1.55 2.38 2.03 1.31 1.95 1.26 Flow resistance (mils) 40 30 30 35 35 25 35 25 Sedimentation Prevention (cm) 1.9 2.5 3.0 1.8 2.0 4.5 2.0 5.0 Storability (particle generation) none none none none none none none has exist

* 1: Coatax WF-268

* 2: Cymel 325

* 3: Silberline Silo-wet TM325AR)

Each raw material was added and the paint physical properties were measured after stirring for 20 minutes at 2000 rpm using a high speed stirrer. Thixo Index was measured by dividing the paint at 60 rpm and 6 rpm, respectively, under the same conditions using a viscometer and dividing the 6 rpm reading into the 60 rpm reading. Flow resistance was measured by ASTM D4400. The sedimentation prevention property measured the height of the clear liquid which filled the liquid up to 20 cm in the glass tube of 25 cm in length and 3.7 cm in diameter, and after standing at room temperature for 15 days. Storage performance was measured on the basis of KSM5000 whether the particles (seed) generation after storage for 4 days at 50 ℃ in a storage container.

The manufacturing method of the present invention does not require a pulverizing and aging process as compared with the manufacturing method of the oil-soluble amide wax-based viscoelastic modifier, which is widely used in the related art, and thus the manufacturing method is simple and time and cost are saved.

The wax thus prepared by the method of the present invention has an effect as a dispersant such as saggingntrol of the paint, anti-settling during storage, maintaining the stability of the paint viscosity according to the stirring conditions, and pigments in the paint. . The amide wax of the present invention is easier to use compared to the inorganic viscoelastic modifiers widely used in the past, and excellent in performance. That is, it is excellent in preventing the settling of pigments, and is effective in controlling flow, stabilizing viscosity, and dispersing pigments. In particular, when applied to water-soluble metal paints (aluminum and mica pigments), it exhibits excellent performance in preventing settling and pigment orientation. When used in paint manufacturing, it has excellent heat resistance and gloss, and there is little phenomenon that solid particles settle and harden during long-term storage. Moreover, it does not affect water resistance after drying of a coating film.

Claims (7)

 Primary diamines having 2 to 8 carbon atoms; Solvent by synthesizing polyamide as a mixture of relatively dimer carboxylic acid and other dicarboxylic acid having 3 to 16 carbon atoms or monocarboxylic acid having 2 to 17 carbon atoms, neutralizing with base to form salt A method for producing a water-soluble amide wax, comprising producing wax in a state in which polyamide is dispersed in phosphorus water. The method of claim 1 wherein the primary diamine is m-xylidediamine, ethylenediamine or 4,4-diamino-diphenylmethane. 2. The process of claim 1 wherein the equivalent ratio of primary diamine to total carboxylic acid is 1.2 to 1.5. The method of claim 1 wherein the dicarboxylic acid is succinic acid, adipic acid, azelaic acid or sebacic acid. The method of claim 1, wherein the monocarboxylic acid is 12-hydroxystearic acid, oleic acid, lauric acid, or stearic acid. The method for producing a water-soluble amide wax according to claim 1, wherein the ratio of the dimer carboxylic acid in the total carboxylic acid is 60% or more in molar ratio. The method of claim 1, wherein the acid value of the polyamide during the polymerization is adjusted to 40 ~ 100mgKOH / g.