RU2401854C2 - Enamel for depositing anticorrosion fireproof bioresistant coating - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to coating materials and can be used in anticorrosion fireproof bioresistant coating of different materials. The enamel is a set including the following (wt %): a semi-finished enamel product from brominated epoxy resin in an organic solvent in which filler materials are dispersed 8.52-13.5, pigments 18.27-25.29 and a rheological agent 1.7-2.7, as well as an amine type hardener. The resin base is synthesised from epoxy resin and tetrabromodiane in molar ratio of 3:1 and temperature 130-150°C in the presence of a catalyst - an oligomer of aromatically conjugated hydroxyphenylene in amount of 0.65-0.75 moles, which does not contain amines and is obtained via oxidative condensation of alkyl resorcin at 250°C.

EFFECT: resin base has long working life, good technological characteristics; the coating is fungus-resistant, has self-extinction after coming out of a gas burner flame UL - 94, V₀ - 0.

6 cl, 7 tbl, 3 ex

Description

The proposed solution relates to polymer chemistry, in particular to polymer paints and varnishes, and can be used in various fields of technology as enamel to obtain anti-corrosion fireproof and biostable coatings on various materials.

A known method for producing bromine-containing epoxy compositions by condensation of di- or polyphenol (US patent No. 3058946 class. 206-42 publ. In 1962) with a diepoxy compound at a temperature of (80 - 180) ° C in the presence of a low boiling tertiary amine, which after completion of the reaction interactions of hydroxyls and epoxy groups of components are distilled off under vacuum. The bromine-containing epoxy resin by this method provides incombustibility of materials with fillers, however, amines taken as a catalyst require distillation, and binders of them in organic solvents are unstable during storage, i.e. unsuitable for use.

Another method for producing a bromine-containing epoxy resin (US patent No. 4075260 kl. 260-830 publ. 1978) is the interaction of tetrabromodiphenylolpropane (tetrabromodian) with diphenylolpropane diglycidyl ether (epoxy resin) at a temperature of (100-180) ° C in the presence of methyltriphenylphosphonium . During the synthesis, mixtures of a bromine-containing product and phosphonium salt are formed. Further use is associated with its dissolution in the base epoxy resin, however, it is impossible to avoid crystallization of the product and its low viability - (3-4) days.

The closest analogue to the proposed method for producing bromine-containing epoxy resin is the method according to auth. USSR No. 952917, Bull. No. 31 dated 08/31/1982 IPC С08L 63/02, where the authors synthesize tetrabromodian with epoxy resin in a molar ratio of (0.9-1.1) to 2.0 at a temperature of (80-180) ° С for (12-14 ) h in the presence of Mannich's acid bases (0.01-0.05) mole. The latter are represented by derivatives of ditridimethylaminomethyl from phenol, resorcinol, diane diglycidylaniline. The viability of such resins is more than 3 months, but during storage, flakes of salt-like compounds appear in the bulk of the resin.

An analysis of the technical literature showed that the use of amines as catalysts for the interaction of brominated products leads to the formation of branched structures or the formation of crystalline and salt-like compounds that adversely affect viability, and coatings and materials formed from them.

To address these shortcomings in the closest analogue, the applicant proposes a technical solution associated with the use of a reactive compound that does not contain amines - polyphenol based on alkylresorcinol -

aromatically conjugated hydroxyphenylene as a catalyst in the synthesis of the epoxidian resin with tetrabromdine to obtain a base resin for the manufacture of enamel.

In the synthesis of a bromine-containing resin (binder, film-forming) in a tetrabromodian melt and a low molecular weight epoxy resin or in a 75 wt.% Solution of these resins in ethyl cellosolve using ARGOF oligomer as a catalyst for (2-4) hours at a temperature of (130-150) ° With the resulting product with wt. fractions of epoxy groups (8-11)%, which is stable during storage, does not crystallize, does not contain salt-like compounds in the mass of flakes.

The applicant does not compare the proposed technical solutions with known solutions for use, because Intends its solution (enamel) for the manufacture of protective coatings. For this purpose, the closest analogue is the solution set forth in the RF patent for the invention No. 2232176 Bull. No. 19 dated 07/10/2004 “Protective coating”, as it includes epoxidized brominated dian and epoxy resin in a film-forming and semi-finished product with mineral additives, which is cured by amine type agents. The specified technical solution due to the use of epoxidized brominated diane in the coating composition increased the moisture resistance of the coating and, accordingly, its protective properties.

However, the specified technical solution has the disadvantages:

- coating formation is carried out at a temperature of 90 ° C for 2 hours;

- in the composition of the varnish solution (the binder has a solvent - cyclohexanone (in the amount it prevails), which is difficult to evaporate and has a smell of hydrocyanic acid.

The above disadvantages do not allow coating for protection from the inside and outside of large-sized structures and structures, because when applying them, it is neither possible to create the required temperature, nor to provide powerful ventilation to evaporate the solvent or eliminate the odor that “scares” the working staff.

Elimination of the disadvantages of the known technical solutions for the preparation of film-forming (synthesis) and for the intended purpose (in the preparation of enamel) and application (application of protective coatings) is the goal of the proposed technical solution.

The goal is achieved by the invention, which includes the synthesis of a film-forming (binder), the preparation of a semi-finished product, as well as the production of enamel coatings.

Enamel for applying an anti-corrosion fireproof bio-resistant coating, which is a kit containing a semi-finished product of an epoxy base resin in an organic solvent and dispersed mineral additives and an organic solvent, an amine type hardener, while it contains 50-60% wt. a solution of the epoxy resin base in an organic solvent obtained by the interaction of the melt of diane resin with tetrabromodian taken in a molar ratio of 3: 1, respectively, for 2-4 hours at a temperature of 130-150 ° C until the content of epoxy groups in the melt is 8-11% wt. . in the presence of a catalyst, followed by dissolving it in a solvent mixture of acetone: xylene: ethyl cellosolve in a mass ratio of 1.3: 1.0: 1.0, respectively. In the presence of a catalyst - 0.67-0.75 moles of aromatically conjugated hydroxyphenylene with a degree of polycondensation n = 0-2 obtained from an alkylresorcinol melt at 240-260 ° C as mineral additives, the enamel prefabricated contains pigment, filler and rheological agent in the following the ratio of the components of the semi-finished product, wt.%:

pigments 18.27-25.29 fillers 8.52-13.5 rheological agent 1.7-2.7 organic solvent 5.22-13.50 the above base resin solution rest,

and the ratio of ingredients in the enamel kit is in parts by weight:

the above semi-finished enamel 100.0 amine type hardener 2.0-35.0.

The enamel is also characterized in that the pigment in the semi-finished product contains red iron oxide and / or titanium dioxide and / or crowns, lead orange and / or lead lemon and / or crowns, lead yellow and / or industrial carbon and / or phthalocyanine blue and / or pigmented chromium oxide and / or strontium chromic acid and / or black iron oxide and / or chromix intended for coatings;

The enamel is also characterized in that it additionally contains fillers in the semi-finished product - microtalc and / or kaolin and / or antimony oxide and / or barium borate and / or micromica.

Enamel is also characterized in that it additionally contains a rheological agent in the semi-finished product - calcined silica (aerosil) and / or bentonite.

The enamel is also characterized in that in the preparation of the enamel, an additional solvent is added — xylene and ethyl cellosolve in wt. ratio different for each type and amount of fillers and pigments.

The enamel is also different in that it contains, depending on the season of application and the specifics of the protective work per 100 wt. including semi-finished mass. including - hexamethylenediamine (alcohol solution) - from 3.6 to 4.0 and / or diethylene triamine from 2.0 to 2.3 and / or polyethylene polyamine from 2.1 to 3.0 and / or low molecular weight polyamides with an amine number from 140 to 300 mg / KOH as solutions in organic solvents from 19.5 to 35.0 and / or gamma-aminopropyltriethoxysilane from 12.0 to 18.0 and / or aminophenol from 7.6 to 10.1 and / or others used for curing epoxy resins.

Examples of the method for producing enamel

1. An example of obtaining a catalyst for the reaction of eposcidian resin and tetrabromodian oligomer ARGOF.

1.1. Source materials:

- oxidizing agent - acid contact tech. sulfuric conc .;

- alkylresorcinol tech. - fraction (270-320) ° C during the distillation of shale oil, the composition is shown in table 1.

1.2. In a reactor with a capacity of 0.1 cubic meters with oil heating, a stirrer, a Dean-Stark trap with a thermometer, 80 kg of alkylresorcinol are loaded in the form of a light yellow melt with a temperature of 70-80 ° C and heated to 100 ° C with stirring, after which through a special funnel load 2.4 kg conc. sulfuric acid and continue heating. The reactor through a Dean-Stark trap is connected to the atmosphere and can be connected to a vacuum system to distill off the condensation water released during the oligomerization of alkylresorcinol. At a temperature of 130-135 ° C, an intensive distillation of water begins, which is taken as the starting point of the synthesis time, further distillation of water when the reaction mass is heated at a rate of (2-3) ° C / min to 250 ° C completes 2/3 of the distillation of water from total amount of 10 l (according to calculation). After exposure at a temperature of 250 ° C for 2 hours, the reaction mass becomes dark red-brown with high fiber-forming properties. The test sample ARGOF contains 5-6 wt.% Volatile substances. For their distillation, a vacuum is applied to the reactor (a vacuum of 500-600 mm Hg) and kept to a volatiles content of no more than 1.2 wt.%, After which the vacuum is removed, the product is cooled to 80 ° C and poured into metal capacities.

The yield of the product is 90 wt.%, The temperature of the onset of its melting is 48 ° C, the pH of the aqueous extract is 4-5, it is soluble in water (partially), completely in acetone and ethyl cellosolve, insoluble in toluene and xylene.

Table 1 The composition of alkylresorcinol No. p / p Name of products in the fraction Content, wt.% Note one Monophenols Max. 1,0 Product Composition distillation can 2 5-methylresorcinol 48-60 change 3 5-ethylresorcinol 10-12 Mixture alkylresorcinol has four Resorcinol 5-7 light yellow color and slight smell of resorcinol 5 2,5-dimethylresorcinol 8-10 6 4,5-dimethylresorcinol 6-8 7 4-methylresorcinol 2-4 8 2-methylresorcinol 1-2 9 Methyl and 1-2 ethyl pyrocatechol 10 Water Max. 1,0

When carrying out the reaction of obtaining the oligomer according to other modes and with a different concentration of the oxidizing agent, a product for another application is obtained.

2. The process of obtaining epoxy film-forming brominated (EPB) - 58 wt.% Resin solution - the basis of enamel.

Reagents are loaded into a reactor with a capacity of 0.1 cu.m / m in the ratio and sequence shown in Table 2. Diane epoxy resin with a temperature of 35 ° C is loaded by gravity from 200 l of barrels and when heating is turned on, it is loaded from a tetrabromdian bag; turn on the mixer, heat the mass to 60 ° C and hold for 1 h, then with the mixer turned off, the melt of alkylresorcinol with a temperature of 70 ° C is loaded into the resin melt with tetrabromdian. The reactor is closed and stirring is carried out for 0.5 h and the temperature is raised to 130 ° C, self-heating of the mixture begins at a rate of (2-3) ° C / min to a temperature of 150 ° C, while the heating is turned off. After 1.5 hours, the heating of the reaction mass ceases, it self-cools for 1 hour to 120 ° C, after which it is turned on and cooled for 100 hours to 100 ° C and dissolved by first draining ethyl cellosolve, then xylene and at a temperature of 35 ° C acetone, taken in wt. a ratio of 1.0 to 1.0 to 1.3, respectively, so that the concentration of the solution is 58.6 wt.%, the content of epoxy groups in the product after exothermy is 10.2 wt.%. The total duration of the reaction and its preparation was 7 hours, the yield of a suitable solution of the base resin was 100 wt.%. To adjust the viscosity of the solution and save starting materials, the composition consisting of the same components after washing the reactor and pipelines is poured into the finished EPB solution (varnish), after which the solution is poured into barrels.

If the epoxy resin has a mass fraction of epoxy groups (20-24)%, then the reaction is completed under the above conditions with the content of epoxy groups (8-11)%, with a lower content of epoxy groups in the initial and finished product, the semi-finished product does not satisfy the viscosity requirements and reactivity, as well as manufacturability. Epoxidian resin with wt. the share of epoxy groups more than 24% industry does not produce.

table 2 The recipe for the receipt of EPB No. p / p Name of reagents Ratio The reaction temperature, ° C The duration of the reaction, h Note mole parts by weight kg example 1 one Dianova epoxy resin with a mass fraction 3.00 100.00 34.00 epoxy groups 23.1% 130-150 3,5 According to the example of claim 2 2 Technical tetrabromodiphenylolpropane 1.00 48.65 16.50 3 The catalyst obtained in example 1 0.76 20.40 6.93

The use of an oligomer catalyst in the reaction of an epoxydian resin with tetrabromodian has been verified with its molar fraction (0.65-0.75), while this ratio is selected in this range from the minimum if the oligomer has a pH of the aqueous extract more acidic and molecular weight higher (about 350 cu) and, conversely, to a maximum value at a less acidic pH of the aqueous extract and a lower molecular weight of the oligomer (about 300 cu). A wider loading range of the oligomer results in materials with other enamel application properties.

Table 3 shows comparative indicators of the properties of EPB obtained by the proposed method and well-known analogues of the production method.

3. The process of preparing a semi-finished enamel

Table 4 shows the formulations for the preparation of semi-finished products of various colors, we describe it on the example of light gray enamel.

In the dissolver, the components indicated in Table 4 are alternately loaded in the indicated sequence, except for the solvents, and they are mixed until a homogeneous mass is obtained at a stirrer speed of 1000 rpm for 1 h, and then the resulting mass is pumped into a bead mill with cooling of the grinding chamber and at the exit from it, the semi-finished product is collected in another dissolver, where it is again mixed to average the color and viscosity for type setting according to the indicators indicated in table 4 (items 1-8), then filtered and packaged in meth Allic tanks with a volume of 20 l of 20 kg.

Change in the ratio of semi-finished product components, including solvents can disturb the suspension balance and color in the semi-finished product and in the enamel, in addition, the abnormal adjustment of its viscosity to the required application method (brush, roller, spray) can also lead to sedimentation of mineral components having a density more than two times higher, than organic ingredients. The dilution should not exceed more than 20 wt.% By weight of the semi-finished product.

Comparison of the properties of the epoxy film-forming brominated (EPB) obtained by the proposed method with known technical solutions

Table 3 No. p / p The name of indicators The value of the indicators EPB proposed solution BEC, prototype according to ASSSSSR No. 952917 Composition 4, Prototype according to patent RU 2232176 one Aggregate state of the product solid solid liquid 2 Mass fraction in terms of dry residue,% - epoxy groups 10.5 9.0 not indicated - organic bromine 21.5 26.6 not indicated 3 Mass fraction of crystals or salt-like compounds are absent 3,7 not indicated four Solvents for use acetone, xylene, ethyl cellosolve and / or mixtures thereof dimethyl sulfoxide, butanol, methyl ethyl cellosolve acetone, xylene, ethyl cellosolve, cyclohexanone 5 Stability while waiting for processing, months 12 3 not specified (usually 12)

Before use, the semi-finished product is thoroughly mixed with a spatula so that no sediment remains at the bottom of the container, after which a hardener is introduced into it with accurate weighing with thorough mixing. The types of hardeners and their quantity are shown in table 6, and the implementation of the invention on the application of enamel and the conditions for the formation of coatings is shown in table 7 - flow chart.

Thus, according to the data in Tables 3 and 5, the proposed technical solution eliminates the disadvantages of analogs both in the synthesis of epoxy film-forming brominated and in the formation of a protective coating to the closest analogue and, in addition, gives enamel and protective coatings properties in terms of processability, fire safety and biostability.

The above allows us to conclude that, by the totality of the features, the proposed technical solution meets the level of the invention.

Comparative indicators of the properties of the proposed technical solution with the known patent RU No. 2 232 176 in the manufacture of enamel and its applicability to obtain a protective coating

Table 5 No. p / p The name of indicators The value of indicators for technical solutions proposed famous one Appearance of film-forming, varnish dark solution not specified 2 The appearance of the prefabricated enamel suspension of any color not specified 3 Viscosity VZ-246 with a nozzle diameter of 6 mm at 20 ° C, s 25-80 not specified four Mass fraction of non-volatile substances in the enamel semi-finished product,% 65 ± 5 not specified 5 The degree of milling of fillers in enamel, microns no more than 50 not specified 6 Drying time for coating no more than 6 not indicated 7 dust holding at 20 ° C, h The curing time of the coating at 20 ° C, h no more than 24 2 at 90 ° C 8 Adhesion to the substrate, score - in a condition of delivery no more than 1 one - after exposure to water for 14 days no more than 1 one 9 Resistance to blow by a ball, cm fifty fifty 10 Elasticity, mm one one eleven Water absorption, wt.% 0.3 0.3 12 Resistance to static coating exposure, h -3% NaCl solution at 20 ° C not less than 48 not specified hot water at a temperature of (95 ± 5) ° С not less than 6 not specified 13 Operating temperature (permissible), ° С 200 not specified fourteen Self-extinguishing of the coating after removal from the flame of a gas burner according to UL - 94, Vo - 0 not specified fifteen Biostability (for the formation of fungi) mushroom resistant not specified 16 The predicted service life of the coating on the steel substrate in salt spray, years (according to the laboratory of AKZ OJSC Silvinit) not less than 7 years not specified

Table 6 Types of hardeners and their quantity No. p / p Name of hardener NTD on a hardener Hardener loading per 100 wt. h. semi-finished product ARGOF-EPB, parts by weight one PEPA - polyethylene polyamide TU 2413-357-00203447-99 from 2.1 to 3.0 2 DETA - diethylenetriamine import from 2.2 to 2.7 3 Hardener No. 1 (50 wt.% Solution of hexamethylenediamine in methylcarbinol (i.e. in ethanol) TU 6-10-1263-77 from 3.6 to 4.0 four Hardener No. 5 (50 wt.% Solution of low molecular weight polyamide PO-300 in ethyl cellosolve) or hardener No. 5 (30 wt.% Solution of low molecular weight polyamide PO-300 in ethyl cellosolve) TU 6-10-1093-76 from 19.5 to 35.0 5 Aminophenol AF-2 (at a temperature below 10 ° C a 66 wt.% Solution in ethyl cellosolve is used) TU 2494-052-00205423-2004 from 8.0 to 9.0 6 AGM-9 gamma-aminopropyltriethoxysilane TU 6-02-724-77 from 14.0 to 16.0

The implementation of the invention upon receipt of the coating gray

An example of the technological process of painting the surface of the primary protection of metal structures.

Application system: ARGOF-EPB enamel in 3 layers at positive temperature

Table 7 Name of operation Technological map Consumption Parameters, data equipment identification one 2 3 four 1. Preparation surface: 1.1 Abrasive blast cleaning of corrosion products, metal buildup, welding spatter, Surface preparation degree Sa to a 2 _^1/2 to Sandblasting apparatus, scrapers, brushes. burrs and sharp edges, cleaning international standard ISO 8501-1: 1988. Answer: sandblaster Control: master welding seams from slag and loose adjacent scale 1.2 Dust removal of the surface and removal of abrasive blasting products Compressed air with a pressure of 0.4-0.6 MPa Industrial vacuum cleaner, estimates, apparatus for blowing the surface with compressed air. Answer: sandblaster Control: master 1.3 Surface degreasing and drying 0.3 kg / m ² Degreasing the surface immediately before painting and no later than: Brushes, rags, wipes, admit? spraying. - than 6 hours after machining when working in the open air; Response: painter - than after 24 hours when working indoors. Control: Master, OTK Solvents: P4, 646, P5, acetone. No moisture or oil stains on the filter paper. It is not allowed to use gasoline and kerosene for degreasing! 2. Coating: Before use prefabricated enamel Response: painter mix thoroughly until Control: master, quality control department 2.1 Mixing the semi-finished enamel ARGOF-EPB with hardener No. 5 (50% solution PO-300) disappearance of sediment at the bottom and add hardener: 100 wt.h. prefabricated enamel add 20.5 parts by weight hardener No. 5 and mix. After the hardener is introduced, the enamel should be kept for 30-40 minutes until the air inclusions are removed. Due to the thixotropy of the ARGOF-EPB enamel, the working viscosity is not standardized. If necessary, enamel with hardener can be diluted with solvents. P4, P5, 5A. Enamel dilution is permissible from 5 to 10% of its mass! Enamel viability - at least 6 hours. 2.2 Application of enamel ARGOF-EPB airless spraying in 3 layers. On the welds, end edges, hard-to-reach spots before painting, a “strip layer” is applied with a brush. Airless Sprayer Drying the strip layer for 2 hours at 20 ° C. Response: painter Interlayer drying at Control: master Enamel consumption for 3 layers 0.75 kg / m ² at a temperature of 5 ° C - 16 hours, at 10 ° C - 8 hours, at 20 ° C - 4 hours, at 30 ° C - 2 hours Indicative Due to the fact that the process Control devices; thickness of one staining can comb type "G-2" layer (with dry held in the open for thickness measurement enamel residue air when exposed wet layer 68 ± 5%): different temperatures and electromagnetic humidity, the criterion for thickness gauge type - wet layer 120-150 applying subsequent "Constant K5" μm layers is a state Response: painter - dry layer 80-100 dry touch coatings Control: master μm GOST 19007-73. 3. Control For coating ARGOF-EPB, Control Devices: application quality working in electromagnetic coverings highly aggressive environments thickness gauge type recommended thickness "Constant K5" finished coating from 250 to 300 microns. Control: OTC, master On the finished surface do not there should be drips neprokrasov, swelling and exfoliation. Benchmarks for paragraphs of table 5 tested on samples witnesses during work.

Notes:

1. The application of varnish and enamel using hardener No. 5 can be carried out at a temperature of at least + 5 ° C and a relative humidity of not more than 85%.

2. The consumption of varnish and enamel is indicated taking into account the hardener and excluding the additionally introduced solvent.

3. Curing of the coating to the degree of “dry to the touch” is considered satisfactory if fingerprints are not left on the coating for 5 seconds.

4. The thickness of the finished coating should not exceed the norm.

5. By prior agreement of the parties, it is possible to replace hardener No. 5 with another hardener while preserving all the coating properties.

6. Immediately after painting work, all equipment should be thoroughly flushed with solvent R-4 or 646.

7. Be sure to keep logs on the preparation and painting of the surface.

8. The results of operational control are recorded in the relevant journals.

9. Upon receipt of negative indicators for any of the indicators, a reason shall be established;

- this reason is eliminated;

- coating is applied again.

Claims (6)

1. Enamel for applying an anti-corrosion fireproof bioresistant coating, which is a kit containing a semi-finished product of an epoxy base resin in an organic solvent and dispersed mineral additives and an organic solvent, an amine type hardener, while it contains a 50-60 wt.% Solution of epoxy resins - bases in an organic solvent obtained by the interaction of a melt of a diane epoxy with tetrabromdian taken in a molar ratio of 3: 1, respectively, for 2-4 hours at a temperature a temperature of 130-150 ° C until the content of epoxy groups in the melt is 8-11 wt.% in the presence of a catalyst, followed by dissolving it in a solvent mixture of acetone: xylene: ethyl cellosolve in a mass ratio of 1.3: 1.0: 1.0, respectively in the presence of a catalyst — 0.65–0.75 moles of aromatically conjugated hydroxyphenylene with a degree of polycondensation n = 0–2 obtained from an alkylresorcinol melt at a temperature of 240–260 ° C; as a mineral additive, the enamel prefabricated contains pigment, a filler, and a rheological agent at the following component ratio ., Wt%:
pigments 18.27-25.29 fillers 8.52-13.5 rheological agent 1.7-2.7 organic solvent 5.22-13.50 the above base resin solution rest,
and the ratio of ingredients in the enamel kit is, parts by weight:
the above semi-finished enamel one hundred amine type hardener 2.0-35.0 2. The enamel according to claim 1, characterized in that the pigment in the semi-finished product contains red iron oxide, and / or titanium dioxide, and / or crown orange lead, and / or lemon lemon, and / or crown yellow lead, and / or carbon black, and / or phthalocyanine blue, and / or chromium oxide pigment, and / or strontium chromic acid, and / or black iron oxide, and / or chromix intended for coatings. 3. The enamel according to claim 1, characterized in that it further comprises fillers in the semi-finished product - microtalc, and / or kaolin, and / or antimony oxide, and / or barium borate, and / or micromica. 4. The enamel according to claim 1, characterized in that it further comprises a rheological agent in the semi-finished product - calcined silica (aerosil) and / or bentonite. 5. The enamel according to claim 1, characterized in that in the preparation of the enamel, the solvent is additionally introduced - xylene and ethyl cellosolve in a weight ratio different for each type and amount of fillers and pigments. 6. The enamel according to claim 1, characterized in that as a hardener it contains, depending on the season of application and the specifics of the protective work per 100 parts by weight prefabricated parts by weight hexamethylenediamine (alcohol solution) - from 3.6 to 4.0, and / or diethylene triamine from 2.0 to 2.7, and / or polyethylene polyamine from 2.1 to 3.0, and / or low molecular weight polyamides with an amine number from 140 to 300 mg / KOH in the form of solutions in organic solvents from 19.5 to 35.0, and / or gamma-aminopropyltriethoxysilane from 12.0 to 18.0, and / or aminophenol from 7.6 to 10.1, and / or others used for curing epoxy resins.