RU2480483C1 - Method of producing alkyd resin - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: method of producing alkyd resin involves feeding and mixing in a reactor an oil-containing component, glycerine and LiOH, and heating the mixture to 230-260°C, followed by vinylation, polyesterification and bringing to the required characteristics by adding a solvent, wherein vinylation is preceded by alcoholysis, distillation of water without an azeotrope and an alcohol test; after the alcohol test the mixture is cooled to 150-160°C and then undergoes vinylation in the presence of vinyl toluene, xylene, phthalic anhydride and di-tertiary butyl peroxide.

EFFECT: high efficiency of the process and low power consumption owing to a shorter time for synthesis of the alkyd mixture; the obtained resin has improved colour characteristics and shorter drying time to 3rd degree.

7 cl, 1 tbl

Description

The invention relates to the field of alkyd resins and can be used in the paint industry.

A known method of producing alkyd resins, presented in the patent of the Russian Federation for the invention No. 2200741 from 2001.10.18. The method is implemented by carrying out the transesterification reaction of vegetable oils, rosin and glycerin in the presence of a catalyst, followed by polyesterification reactions with phthalic anhydride and polycondensation when heated. Lead 2-ethylhexanate in the amount of 0.018-0.03 wt.% In the form of a solution in white spirit was proposed as a catalyst at the transesterification stage. At the polycondensation stage of the resin, a phenol resin based on para-tert-butylphenol and formaldehyde in an amount of 3-4 wt.%.

In a variant of the method, 2-ethylhexanate in an amount of 0.01-0.017 wt.% In the form of a solution in white spirit is used as a transesterification catalyst, and at the stage of polyesterification of the resin, 5.36-11.61 wt.% A mixture of benzoic and para- tert-butylbenzoic acids in a ratio of respectively 1: 1.5-2.

Accelerated drying time of paints and varnishes was noted, but only when using capacitive-type reactors of a relatively small volume (up to 5.0 m ³ ).

The use of paints and varnishes in the production process along with capacitive-type reactors of flow reactors also leads to an acceleration of the reaction, but only with a small volume of production.

There is also a method of producing alkyd resins according to the RF patent for invention No. 2340631 dated July 5, 2007, comprising mixing in a capacitive reactor connected to a flow tube reactor, vegetable oils and polyhydric alcohol in the presence of a catalyst and when heated, and the subsequent polyesterification operation in the presence of a dicarboxylic acid acids and xylene. At the stage of mixing the reaction mass, a 10% solution of lead 2-ethylhexanate is used as a catalyst. The supply of the catalyst is carried out through a dispenser included at the inlet of the flow reactor at a speed of not more than 10 l / min. At the polyesterification stage, a 10% solution of paratoluenesulfonic acid in xylene is added to the reaction mass at a rate of not more than 10 l / min

The disadvantage of this method is the lengthy synthesis process.

The closest solution to the proposed method for producing alkyd resins is the method according to US patent No. 3445857 from 07/15/1969, including the operation of vinylation in the presence of a LION catalyst.

In accordance with this method (Example No. 11 of the patent), vinyl toluene is added to alkyd resins, which ensures compatibility with both aliphatic and aromatic solvents and allows alkyds to be modified with a wide range of film formers. Vinyl alkyds have increased hardness, excellent gloss, weather resistance, acid and alkali resistance.

Vinyl alkyds can be applied by brush, roller, pneumatic or airless spray. Vinyl alkyd-based coatings can easily be overlapped with other coatings and can be easily sanded.

The traditional synthesis of vinylated alkyds includes the following operations:

LOADING. Sunflower oil (options: soybean, linseed, distilled tallow oil - DTM, fatty acids of tallow oil - GIT) is heated in the reactor to 155-160 ° C and water is distilled off without azeatrop for 1.5-2.5 hours;

VINYLING. Then a mixture of vinyl toluene and xylene is prepared, which is added uniformly to the heated oil over a period of 5-6 hours. The vinylization process is ongoing. The resulting mixture is stirred for 3-4 hours to a dry residue or a content of non-volatile substances of 94.5%. Glycerin and LiOH (0.5-1 h) are added to the mixture and heated to 240-245 ° C (1-1.5). At this point, the entire azeatrope is collected at the receiver;

Polyesterification. Phthalic anhydride and xylene are charged, a polyesterification reaction is carried out. The mixture is kept at 240-245 ° C for 6-7 hours, until it passes the test for phthalic anhydride. Check the readiness of the mixture for every hour;

Test for phthalic anhydride (FA) is as follows. 4.09 parts of the reaction mixture and 1 part of FA are mixed in a flask, heated to 240 ° C for 15 minutes. The reaction mass is considered to be finished with a viscosity of 50-80 s and an acid number of 10. Upon cooling, the mixture should remain transparent.

TYPING - bringing to the desired performance. After passing the FA test, the mixture is cooled to 150-160 ° C (1-1.5 hours) and adjusted to the desired values by adding a solvent (1-2 hours).

The total synthesis time is 19-25.5 hours.

The disadvantage of this method is the length of the synthesis time, which reduces the productivity of the process and increases energy consumption.

The objective of the proposed solution is to increase the productivity of the process and reduce energy consumption by reducing the synthesis time of the alkyd mixture.

To solve this problem, a method for producing an alkyd resin, including loading and mixing an oil-containing component, glycerin and LiOH in a capacitive reactor, as well as heating the mixture to 230-260 ° C and subsequent operations of vinylation, polyesterification and adjusting to desired parameters, changed the sequence of operations and composition of components. Before the operation of vinylation, the process of alcoholysis is carried out, distillation of water without an azeatrop, and an alcohol test. After completion of the alcohol test, the mixture is cooled to 150-160 ° C and then the vinylation operation is carried out in the presence of vinyl toluene, xylene, phthalic anhydride and di-tertiary butyl peroxide.

The introduction of a new component in the proposed process for the manufacture of alkyd resin helps to increase the efficiency of the catalyst and accelerate the synthesis process, which reduces energy costs and increases the productivity of the process, as well as improves the operational and technological properties of the final product. Carrying out the vinylation process after the operation of alcoholysis and distillation of water without an azeatrope also helps to speed up the process.

The method is as follows.

For 1-1.5 hours, a prescription amount of sunflower oil (or oil-containing component: soybean, linseed, distilled tallow oil - DTM, fatty acids of tallow oil - GIT) is loaded into the reactor in an amount of 15-30%, glycerin in an amount of 3-15 %, initiator LiOH - 0.003-0.006%.

The mixture is heated to 230-260 ° C under nitrogen atmosphere and stirred for 2-3 hours. Next, carry out the process of alcoholysis and distillation of water without an azeatrop (3-4 hours). During this operation, the oils are “compacted”, the molecular weight increases. The degree of "compaction" is checked by conducting an alcohol test (see I.S. Okhrimenko, V. V. Verholantsev. "Chemistry and technology of film-forming substances", Leningrad, Chemistry, 1978, p. 191). This is a test to dissolve the “compacted” oil in ethyl alcohol. Ordinary oil does not dissolve in alcohol, but “compacted” dissolves. After the "compaction" of the oil proceed to the second stage - vinyl.

Cool the mixture to 150-160 ° C for 1.5-2 hours. A mixture of vinyl toluene (BT) in the amount of 12-30%, di-tertiary butyl peroxide in the amount of 0.3-1.2%, xylene 0.5-2.5% and phthalic anhydride is added to the reaction mass - 8-18 % evenly for 0.5-1 hours with stirring. Vinyling is carried out for 2-3 hours.

Azeatrop fully returns to the reactor.

Next, the polyesterification process is carried out to a non-volatile content> 94% (2-3 hours).

The resulting mixture is dissolved in white spirit or TS-1 in an amount of 30-55% to the desired values.

The whole process of manufacturing alkyd resin by the proposed method takes 14-19 hours, which gives a savings of 5 hours.

In addition, as shown by comparative studies, the use of an additional component of di-tertiary butyl peroxide, as well as a change in the sequence of operations, allowed to improve the technological and operational parameters of the obtained product. The following is a comparative table of the parameters of alkyd resin obtained using the known method and proposed in the application.

Table No. Indicators Known method The proposed method one WITH,% 48-52 48-52 2 Viscosity, s., According to B3-246 with a nozzle diameter of 4 mm at a temperature of 20.0 + 0.5 ° C 50-80 50-80 3 Acid number, mg KOH / g, not more than 8-10 8-10 four Color, on an iodometric scale 15-20 8-10 5 Synthesis time, h 19-25.5 14-19 6 Drying time to st. 3, h, at a temperature of 20.0 + 2.0 ° С 5-6 3-4

As can be seen from the table, the resin made by the proposed method has improved significant characteristics in color and drying after application.

Claims (7)

1. A method of producing an alkyd resin, comprising loading and mixing an oil-containing component, glycerin and LiOH in a capacitive reactor, as well as heating the mixture to 230-260 ° C and subsequent operations of vinylation, polyesterification and adjusting to desired values by adding a solvent, characterized in that before the operation of vinylation, the process of alcoholysis is carried out, water is distilled off without an azeatrope and an alcohol test, after the completion of the alcohol test, the mixture is cooled to 150-160 ° C and the operation is vinylated in the presence of vinyl toluene, xi lola, phthalic anhydride and di-tertiary butyl peroxide. 2. The method according to claim 1, characterized in that as oil-containing components use sunflower, soybean, linseed, distilled tallow oil or fatty acids of tallow oil in an amount of 15-30% of the total reactive mass. 3. The method according to claim 1, characterized in that the amount of di-tertiary butyl peroxide is 0.3-1.2% of the total reactive mass. 4. The method according to claim 1, characterized in that the amount of vinyl toluene is 12-30% of the total reactive mass. 5. The method according to claim 1, characterized in that the amount of xylene is 0.5-2.5% of the total reactive mass. 6. The method according to claim 1, characterized in that the amount of phthalic anhydride is 8-18% of the total reactive mass. 7. The method according to claim 1, characterized in that the amount of xylene is 0.5-1.2% of the total reactive mass.