JPS60179452A - Production of maleinized alkyd resin emulsion - Google Patents

Abstract

PURPOSE:To produce the titled emulsion having ecxcellent storage stability and water-dispersibility, by dispersing a neutralized maleinized alkyd resin dissolved in a low-boiling alcohol solvent in water and removing a specified quantity of the solvent. CONSTITUTION:A maleinized alkyd resin having an acid value of 10-60 obtd. by reacting maleic anhydride with an alkyd resin modified with a (semi)drying oil and/or fatty acid is dissolved in a low-boiling alcohol solvent such as n- butyl alcohol, before or after said maleinized alkyd resin is neutralized with a neutralizing agent such as diethanolamine. The soln. of the resin is then dispersed in water and at least 30wt% said alcohol solvent is removed, thus producing the titled emulsion. Use of the low-boiling alcohol solvent facilitates dispersion of the resin in water and affords an emulsion of finely divided maleinized alkyd resin. Further, by removing the solvent, an emulsion can be obtd. which has excellent storage stability and gives a coating film having excellent resistance to water and corrosion.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a maleated alkyd resin emulsion, and more particularly to a method for producing a maleated alkyd resin emulsion that has excellent water dispersibility and extremely good storage stability. .

Recently, water-soluble alkyd resin paints have been widely used as low-cost industrial paints. However, in conventional water-soluble alkyd resin paints, the method of introducing the acid necessary to make the alkyd resin water-soluble is generally carried out by halfesterization using 7-tar acid anhydride, trimellitic anhydride, etc. . However, the water-soluble alkyd resin is easily hydrolyzed due to the anchimeric effect, and the alkyd resin is insoluble in water, resulting in poor storage stability. Furthermore, since the main chain of the water-soluble alkyd resin also has an ester bond, it is hydrolyzed by water and a neutralizing agent, and the main chain of the water-soluble alkyd resin is cleaved, resulting in poor storage stability. Attempts to improve these drawbacks include (1) using a water-soluble alkyd resin with a low acid value, (2) JP-A-57-
As shown in Japanese Patent No. 200461, it has been proposed to use a partial combination of an acid group-containing alkyd resin and a hydroxyl group-containing alkyd resin.

Regarding (1) above, by using a water-soluble alkyd resin with a low acid value, the resistance to hydrolysis by water and a neutralizing agent can be improved. 1-or 1-A method of simply lowering the acid value results in poor water dispersion stability, and it is difficult to maintain a balance between the two. -! Regarding (2) above, the condensation reaction between the two is slow, making it difficult to manufacture, and furthermore, the hydroxyl group-containing alkyd resin needs to have a hydroxyl value of 50 or more. ! The coating film formed using the above-mentioned condensation product has many hydroxyl groups in Coating 1 even after oxidative curing, and the water resistance and corrosion resistance of Coating 8Q are insufficient to increase hydrophilicity.

Furthermore, when an alkyd resin containing a large number of hydroxyl groups is used in a water-dispersed state, its hydrophilicity becomes high and water and neutralizing agent are drawn into the alkyd resin, resulting in poor storage stability and poor coating film quality. No adverse effect on oxidation hardening.

In addition to (1) and (2) above, there is a method of adding maleic anhydride to an alkyd resin. It has a good balance with the water, prevents hydrolysis of the resin, and has excellent storage stability. However, it is not easy to improve the water content of the maleated alkyd resin, and generally requires a considerable amount of cellosolve organic solvent.

When this product is stored, the cellosolve organic solvent in the water-dispersed maleated alkyd resin redissolves the resin constituting the parent xylem on the particle surface as the temperature changes during storage. This causes a change in particle size and an increase in viscosity. Furthermore, the barrier of the fatty acid groups constituting the lipophilic moieties on the particle surface and inside the particles is damaged, and as a result, hydrolysis inside the particles is also promoted, resulting in poor storage stability and the aqueous dispersion of the maleated alkyd resin. The coating film formed from the resin had poor properties such as water resistance and ITr1 corrosion resistance, and was not satisfactory.

Starting from scratch, the authors have made extensive research into a method for producing maleated alkyd resin emulsions that do not have the above-mentioned drawbacks. When dispersing maleated alkyd resin in water,
By using an alcoholic solvent or a low boiling point organic solvent that is compatible with the maleated alkyd resin and has an affinity for water, the maleated alkyd resin can be easily dispersed in water, and at the same time, the viscosity can be reduced in fractions. It is possible to obtain a maleated alkyd resin emulsion in the form of fine particles with no sedimentation, and furthermore, by removing the alcohol-based low-boiling organic solvent in the maleated alkyd resin emulsion, the storage stability is extremely excellent, and the coating process is improved. It has been discovered that a maleated alkyd resin emulsion with excellent water resistance and corrosion resistance can be obtained, and the present invention has been completed.

That is, the present invention provides a maleated alkyd resin in which maleated alkyd wax having an acid value of 10 to 60 is dissolved in an alcoholic low-boiling maple solvent before or after neutralization with a neutralizing agent. The present invention relates to method i for producing a maleated alkyd resin emulsion, which is characterized in that a maleated alkyd resin emulsion is dispersed in water, and then 30% by weight or more of the organic solvent is removed.

The b-sized inylated alkyd resin used in the present invention is mainly obtained by annealing (semi-)drying oil and/or its fatty acid, polybasic acid, -basic acid and polyhydric alcohol, and further contains anhydrous maleic acid. The (semi-)drying oils and/or fatty acids used for the acid reaction include, for example, linseed oil, safflower oil, soybean oil, sesame oil, poppy seed oil, linseed oil, hempseed oil, and budok kernel oil. , corn sorghum oil, tall oil, sunflower oil, if% oil, walnut oil, rubber seed oil, tung oil,
Examples include dehydrated castor oil, dehydrated castor oil, these fatty acids, and fatty acids. Among them, linseed oil, tall oil, which is easily maleated and has good water dispersibility,
Preferably, soybean oil and their fatty acids are used.

The polybasic acid is a compound having 2 to 4 carboxyl groups in one molecule. Specifically, for example, phthalic acid, isophthalic acid, terephthalic acid, trimeric acid, ) acid, tetrahydrophthalic acid, cono-phosphoric acid, maleic acid, adipic acid, cepatic acid, azelaic acid, hymic acid,
Itaconic acid, methylcyclohexentricarboxylic acid, crotonic acid, pyromellitic acid, anhydrides thereof, and the like can be used. Among them, phthalic acid, isophthalic acid, and benzoic acid, which do not contain the above-mentioned fatty acids and are generally used in the production of alkyd resins, are used. ,
Examples include Bacterial butylbenzoic acid, methylbenzoic acid, non-drying oil fatty acids, etc.

Among these, benzoic acid is preferred because it is low cost and has high coating 111J hardness.

Polyhydric alcohols are alcohols having 2 to 6 hydroxyl groups in one molecule, and specifically include the following: ethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol, butanediol, decanediol, Examples include diethylene glycol, bentanediol, neopentyl glycol, glycerin, trimethylolethane, trimethylolpropane, penquerythritol, flubitol, 1.4 cyclohexane dimetatool, tricyclodecane dimetatool, tris isocyanurate, and the like. The alkyd resin components described above can be used alone or in combination of two or more.

The alkyd resin is produced by combining the above-mentioned components in an inert gas atmosphere according to a synthesis method known per se.
This can be carried out by carrying out a dehydration condensation reaction at 50°C for about 3 to 10 hours.

Next, the synthesis of the maleated alkyd resin is carried out by mixing the mixture of the above 17 alkyd resin and maleic anhydride with a concentration of about 150 to 230
This is carried out by reacting at a temperature of about 1 to 5 hours. The acid value of the maleated alkyd resin thus obtained is 1.
It needs to be in the range of 0 to 60, preferably in the range of 20 to 30.

When the acid value is less than 10, water dispersion becomes difficult, and when it is more than 60, the water resistance of the coating film is impaired.

The oil strength of the maleated alkyd resin used in the present invention,
It is in the range of 15-70, preferably in the range of 20-60, more preferably in the range of 30-55. When the oil length is less than 15, the addition strength of maleic anhydride becomes small and a stable maleated alkyd resin emulsion cannot be obtained.

Conversely, if it is more than 70, the water resistance of the coating film will be impaired.

The viscosity of the maleated alkyd resin used in Kizari 1 is, but not limited to, class 60' (i% butylcellosorg diluted solution with a Gardner foam viscosity value of 0 to Z5, preferably in the s-Z3 range, Furthermore, it is in the U-Z range.If the value of Gardner foam viscosity is small (O), water dispersion becomes easy, but the stability of the emulsion deteriorates, making it difficult to balance the two. That's funny. Furthermore, the water resistance of the coating film is also poor.

On the other hand, if the value is larger than Z5, water dispersion becomes difficult and the amount of organic solvent necessary for water dispersion increases, which is not preferable.

The alcoholic low boiling point organic solvent used in the present invention is
It is a solvent for water dispersing maleated alkyd resin for water dispersion, and it has a polar group that has affinity and compatibility with maleated alkyd resin and also has a strong affinity for water, and furthermore, the organic solvent is removed. Since it is something that does i, one with a fair balance is used.

Such solvents include, for example, the formula: 10-CnII2n+
1 (in the formula, n is an integer from 6 to 6), such as --ethyl alcohol, n-furobyl alcohol, isopropyl alcohol, n-
': (Cyl alcohol, isobutyl alcohol, 5ec
-7' tyl alcohol, tert-7' tyl alcohol, isoamyl alcohol, 5ec-amyl alcohol,
tert-amylalcoholna n2m-o-c, H2T) +t (in the formula, m 2 to 6
represents an integer of p 1 to 2, provided that
m + p does not exceed 5. ), examples of which include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, and propylene glycol monomethyl ether. In the Drt notation, it is preferably a solvent having HO-cnHz i+1.

Here, the term "low boiling point" means that the boiling point temperature range is approximately 0℃.
The temperature is approximately 150℃.

The formulation of the 81F solvent is preferably 5 to 100% by weight of the maleic alkyd resin solid content, and preferably 1% by weight to 20 to 60% by weight of the maleic alkyd resin. If the total amount of solvent is less than 5%, it will not be effective for water dispersion, and on the other hand, if it is more than 100% by weight, it will have good solubility in water and the force Z will cause water dispersion. 17, and the manufacturing cost also increases. Also, for the above-mentioned shaving, two or more pieces of silk can be used alone.

There is no problem in using other solvents and plasticizers than those mentioned above for the purpose of improving film formation.

As a neutralizing agent 11, ammonia and organic amines are used to stabilize the water content of the maleated alkyd side fat, such as primary, secondary or tertiary alkyl amines, Methylamine is a representative example.
Ethylamine, propylamine, butylamine, amylamine, dimethylamine, diethylamine, dipropylamine, dibutylamine, trimethylamine, triethylamine, tripropylamine, mojleforin; primary, secondary or tertiary alkanolamine, representative Examples include monoethanolamine, jetanolamine, dimethylethanolamine, and diethylethanolamine. Among these neutralizing agents, diethylamine, triethylamine, and dimethylethanolamine are preferred because they have good dispersibility, remain during coating, and have high volatility.

Further, the above neutralizing agents can be used alone or in combination of two or more. The use of a neutralizing agent is generally 1.1) to 1 to 2.0, or 1 to 2.0, or 3 to 1. (This is the current season.

Next, a method for producing the maleated alkyd 4M+11ffl emulsion of the present invention will be described. First, the maleated alkyd resin No. 111 is neutralized with the neutralizing agent and then dissolved in the alcoholic low-boiling organic solvent. If neutralization has not been achieved, after neutralization, water is gradually added dropwise to the maleated alkyd resin neutralized solution while stirring for 1 hour to cause phase inversion. Obtain Rekidoki 11 effect emulsion.

In addition, the emulsion temperature when water dispersing is 20~
Preferably, the temperature is 60°C. Next, the alcoholic low-boiling organic solvent contained in the obtained emulsion is removed. The removal method can be easily carried out using a conventional method under normal pressure or reduced pressure. The temperature at which this alcohol-based low-boiling point organic solvent is removed is not particularly limited, but
It is preferable to carry out the reaction in the range of 60°C to 60°C. Also, the amount of alcohol-based low-boiling organic solvent removed is 30% of the blended solvent.
The bite rate is at least 50% by weight, preferably at least 50% by weight, and more preferably at least 80% by weight. The amount of alcohol-based low-boiling organic solvents removed is 30'! If it is less than 11%, the storage stability of the D-maleated alkyd (I-fat emulsion) is poor, and the water resistance and corrosion resistance of the coating film after the storage test cannot be satisfied. When removing, water and neutralizing agent are also removed azeotropically, so it is necessary to add water and neutralizing agent as necessary.

The solid content of the maleated alkyd resin emulsion obtained by the present invention is, but is not limited to, 10 to 65% solids.
A vision of 25 to 60 weight.

% range. It is also manufactured so that the average particle diameter measured by turbidity method is 0.5μ or less, preferably 0.2μ or less. If the average particle size is larger than 5μ, the sedimentation stability of the maleated alkyd resin emulsion is poor, the broken particles are not stable, resulting in poor hydrolysis resistance, and the coating film has poor water resistance and corrosion resistance. (1) also gets worse.

The turbidity method referred to here is based on the literature CBull, Industrial, Chemi, which measures a water-diluted clear emulsion with a spectrophotometer and calculates the absorbance ratio using the following formula.
cal, Reasercll VoL, 42P145~1
52 (1964):), the average particle diameter was determined using the calibration curve described in .

The maleated alkyd resin emulsion of the present invention further includes @ size, a pigment dispersant, a dryer, an antifoaming agent, a thickener,
Aqueous resins other than those mentioned above may also be optionally blended.

The coating formed from the emulsion obtained according to the present invention is sufficiently crosslinked and cured at room temperature, but when heated in the presence or absence of amino acid resin, etc., it cures in a short time and exhibits water resistance, Good coating properties such as corrosion resistance can be obtained.

Next, the present invention will be explained in more detail with reference to Examples and Comparative Examples. Hereinafter, parts and % weight h) parts and heavy viscosity %
Examples 1 to 4 The following IJ7. 548 parts of isophthalic acid 593 parts of pentaerythritol 523 parts of benzoic acid 1638 parts of linseed oil 8h acid 7 parts of dibutyltin oxide were added and heated to 240°C with stirring under a nitrogen atmosphere. The leg-1 water condensation reaction was carried out for 7 hours until . Continue to lower the temperature to 200℃,
133 parts of maleic anhydride was added, and a Yareinich reaction was carried out at 200°C for 3 hours.

A maleated alkyd resin having a resin acid value of 45 and a Gardner viscosity (60% n-butyl cellosolzo solution RE) of W was obtained. Next, add 100 parts of the maleated alkyd resin to
After adding 30 parts of the alcoholic low-boiling point organic solvent of the present invention shown in 1 above and further neutralizing with 1.0 equivalent of triethylthymine, clean water was added and an emulsification fraction was carried out to obtain an emulsified dispersion. Next, while stirring the anal emulsified dispersion liquid, the temperature of the dispersion liquid was increased to 40°C.
The alcohol-based low-boiling organic solvent was distilled off under reduced pressure to obtain maleated alkyd resin emulsions of Examples 1 to 4. Table IK shows the properties and storage stability test results of the maleated alkyd resin emulsion obtained. The coating 19 performance test results of this product are shown in Figure 2.

Comparative Examples 1 to 9 30 parts of the organic solvent shown in Table 1 was added to 100 parts of the maleated alkyd resin, and the mixture was further neutralized with 1.0 equivalent of triethylamine. Then, clean water was added to carry out an emulsification fraction. Comparative Examples 1 to 9 A maleated alkyd t#ite emulsion was prepared. Table 1 shows the properties and storage stability test results of the maleated alkyd (pre-sold emulsion). In Comparative Examples 1 to 4, the organic solvents were methyl alcohol, acetone, methyl ethyl ketone,
I tried using the same amounts instead of toluene and ethyl acetate, but it turned out that water dispersion was impossible.

1) Residual solvent amount: indicates weight % based on resin solid content.

2) Viscosity: Centivoise value when measured with a B-type viscometer (rotation speed: 6) 3) Molecular weight distribution state: Nigel permeation.

It was measured by chromatography (using HLC manufactured by Toyo Soda Co., Ltd., and the solvent was Tetrahydro7ran) and compared with the initial molecular weight distribution state.

Table 2 [Coating film performance test] The solid content of the maleated alkyd resin emulsion compositions obtained in Examples (1) to (3) was
Dainippon Ink Co., Ltd. (trade name: ``Deiknate'', cobalt metal) added 2% and painted on a mild steel plate.

2 (after drying for 7 days at 1° C. and 75% relative humidity, it was subjected to the test.

3) Adhesion: 100 In2-width goblets were made, and cellophane adhesive tape was put on them to mark them, and the number remaining was expressed.

4) Workability: The degree of cracking is shown using a DuPont impact tester under the conditions of rod diameter = 1/2 inch and load = 50Of.

5) Water resistance: The coated surface was soaked in clean water at 20°C for 2 days and the condition of the coated surface was visually evaluated.

6) Gel fraction: indicates the acetone elution residue.

Claims (1)

[Claims] A maleated alkyd resin having an acid value of 10 to 60 is dissolved in an alcohol-based low-boiling organic solvent after being neutralized with a neutralizing agent, and then the maleated alkyd resin neutralized product is dispersed in water. 1. A method for producing a maleated alkyd resin emulsion, the method comprising: converting the organic solvent into a maleated alkyd resin, and then removing 30% by weight or more of the organic solvent.