RU2307143C2 - Enamel for production of the weather-resistant, corrosion-resistant, radiation-proof and the decontamination coatings - Google Patents

Abstract

FIELD: chemical industry; shipbuilding industry; aerospace industry;, atomic power industry; petroleum industry; food-processing industry; production of the enamels for protection of the metallic, wooden and other types of surfaces operating under conditions of the especially hazardous environments.

SUBSTANCE: the invention is pertaining to the enamel used for production of the weather-resistant, corrosion-resistant, radiation-proof and decontaminated coatings, which may be applied in shipbuilding, aerospace engineering, atomic power engineering, and also in petroleum and the food-processing industry for external and internal works at protection of the metals, wood, rubber, concrete, bricks, slate surfaces, which are operating under conditions of the especially of aggressive environments. The enamel represents the composition including 100 mass shares of the semi-finished enamel product and 2.1-28.6 mass shares of the curing agent of the amine type. The semi-finished enamel product contains the following ratio of the ingredients (in mass %): 17-30 - pigments, 7-15 -the mixtures of microtalcum, the caolin and micromica as the filler, 5.22-6.93 - the organic solvent, the remaining - 50-60 mass % - the solution of the epoxy pitch-basis in the organic solvent. The degree of the polycondensation in the organic solvent of the pitch-basis compound makes n = 0-2. The epoxy pitch-basis is produced by epoxidation of the aromatic-conjugated hydroxy phenylene having the degree of the polycondensation of n = 0-2 produced from dihydricphenol or alkylresorcin. Epoxidation of the hydroxyphenylene conduct in the melt at the temperature of 120-165°C at presence of 0.15-0.35 mass % of 2,4,6-tridimethylaminomethylphenol up to the content of the epoxy groups of 10.1-11.0 mass %. The invention allows to improve the enamel stability against the actions of the atmosphere, corrosion, radiation and the means of the decontamination.

EFFECT: the invention allows to improve the enamel stability against the actions of the atmosphere, corrosion, radiation and the means of the decontamination.

8 cl, 4 tbl, 8 ex

Description

The present invention relates to paints and varnishes and can be used for external and internal work in the protection of metals, wood, rubber, concrete, brick, slate surfaces, operating in particularly aggressive environments.

Known widely used in industry is the enamel EP-525 (GOST 22438-85, Publishing House of Standards, 1985), which is a suspension of pigments and fillers in a solution of epoxy resin E-41 in a mixture of organic solvents with the addition of hardener No. 1. However, it has limited atmospheric resistance.

The closest technical solution to the proposed one is the solution described in the RF patent for invention 2 221816 (Bull. No. 10 from 27b, 10.27.2004), where the oligomer for the binder composition is obtained by oxidative polycondensation from resorcinol, alkylresorcinol or pyrocatechol at a temperature of 220-250 ° C in the presence of concentrated sulfuric acid, followed by epoxidation with a low molecular weight Dian-based resin at a temperature of up to 120 ° C to wt. the proportion of epoxy groups is 7-8%. The specified technical solution has the disadvantage that during polycondensation in the reaction mass there remains a significant (up to 17% by weight) of the starting components, which are difunctional and require the epoxidation of an equivalent amount of diane epoxy resin, which reduces the proportion of epoxidized oligomeric product in the finished product, which is target. Upon receipt of oligomers with a lower content of the starting components, their molecular weight increases to 400-500 cu, which leads to the formation of insoluble fractions, and the product is not subjected to epoxidation-curing. In addition, when working with a product containing more than 5% of the starting products that sublimate have an unpleasant odor, especially when heated.

At the same time, during the epoxidation of an oligomer (hydroxyphenylene with a degree of polycondensation n = 0-2) in a toluene solution, the reaction proceeds slowly and its temperature cannot be raised above 110 ° C (boiling of toluene), because possible release of the reaction mass or a large loss of toluene, resulting from the reaction, a decrease in wt. the proportion of epoxy groups up to 7-8% occurs due to the production of branched products, leading to an unjustified increase in the synthesis time and to a decrease in the adhesion, elasticity and hardness of enamel for a given number of epoxy groups. At the same time, branched epoxidation products require more solvents to dilute the enamel prefabricated, which leads to an increase in the time of their evaporation during drying on the substrate. The technical task of the proposed solution is to eliminate the above disadvantages.

The technical result is achieved in that the enamel for coating, which is a kit comprising a semi-finished enamel containing a solution of an epoxy resin base in an organic solvent and an amine type hardener, where the epoxy resin base is obtained by epoxidizing aromatically conjugated hydroxyphenylene having a degree of polycondensation n = 0 -2, obtained from diatomic phenol or alkylresorcinol, characterized in that the semi-finished product contains 50-60 wt.% - a solution of epoxy Dianova base resin, with a degree the polycondensation in the organic solvent of the base resin is n = 0-2, the epoxidation of hydroxyphenylene is carried out in the melt at a temperature of 120-165 ° C in the presence of 0.15-0.35 wt.% 2,4,6-trisdimethylaminomethylphenol to the content of epoxy groups 10 , 1-11.0 wt.%, And additionally the enamel prefabricated contains pigments, the filler is a mixture of microtalc, kaolin and micromica, an organic solvent, in the following ratio of ingredients in the enamel prefabricated, in wt.%:

pigments 17-30 the above filler 7-15 organic solvent 5.22-6.93 the above epoxy solution rest

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

the above semi-finished enamel one hundred amine type hardener 2.1-28.6

In addition, the enamel is characterized in that the pigment in the semi-finished enamel contains red iron oxide pigment, and / or titanium dioxide, and / or crown lead molybdate, and / or crown lead lemon, and / or crown lead yellow, and / or carbon , and / or phthalocyanine blue, and / or chromium oxide pigment.

In addition, the enamel is characterized in that the semi-finished enamel further comprises an aerosil filler.

In addition, the enamel is characterized in that the solution of the epoxy resin base in the semi-finished enamel contains a mixture of organic solvents - acetone and toluene in a ratio of 3: 1.

In addition, the enamel is characterized in that the prefabricated enamel as an organic solvent contains xylene and ethyl cellosolve in an amount providing the desired viscosity of the prefabricated enamel.

In addition, the enamel is characterized in that as an amine type hardener it contains a 50 wt.% Solution of hexamethylenediamine in methylcarbinol in an amount of 3.4-4.0 wt. parts.

In addition, the enamel is characterized in that as an amine type hardener it contains a low molecular weight polyamide with an amine number of 140 to 300 in an amount of 19.5-35 wt. parts.

In addition, the enamel is characterized in that as an amine type hardener it contains 2.0-3.0 parts by weight. polyethylene polyamine or diethylene triamine.

Semi-finished enamel is a suspension of pigments and fillers in a solution of enamel base - epoxidized aromatically conjugated hydroxyphenylene (ARGOF-3E) in a mixture of organic solvents, while the concentration of the semi-finished product is taken 50-60 wt.% The use of semi-finished product with a concentration of less than 50% leads to enamel with low viscosity and solids content, when the concentration of the semi-finished product is more than 60%, it is difficult to grind the ingredients - pigments and fillers below the required 40 microns and, in addition, additional dissolution, which can disrupt the suspension balance.

The following is an example of a schematic formula of ARGOF-3E-aromatically conjugated hydroxyphenylene obtained from diatom phenol, epoxidized with diphenylolpropane epoxy resin:

n=0÷2

n = 0 ÷ 2

where n ₁ = 0 ÷ 2,

Aromatically conjugated hydroxyphenylene (ARGOF-3) can be obtained from resorcinol, pyrocatechol, pyrogallol and hydroquinone, as well as from alkyl substituted resorcinol obtained by distillation of oil shale products.

The composition of the distillation products are shown in table 1.

Table 1 No. p / p Name of fraction Content, wt.% Note one. Monophenols Max. 1,0 Product Composition 2. 5-methylresorcinol 48-60 distillation can 3. 5-ethylresorcinol 10-12 change. four. Resorcinol 5-7 A mixture of alkylresorcinol 5. 2, 5-Dimethylresorcinol 8-10 has a light yellow 6. 4,5-dimethylresorcinol 6-8 color and faint odor 7. 4-methylresorcinol 2-4 resorcinol 8. 2-methylresorcinol 1-2 9. Methyl and ethyl pyrocatechol 1-2 10. Water Max. 1,0

The process of obtaining ARGOF-3 from the above products consists in their polycondensation with the release of water at a temperature of (200-250) ° C in the presence of sulfuric acid (n-toluenesulfonic acid, benzenesulfonic acid, etc.) to a degree of polycondensation n = 0-2, yield (89 -91) wt.%. The product has a red-brown color (black in bulk), melting point (65-85) ° С. The properties of the obtained oligomers for use as a component for epoxidation or as an independent base of enamels or a modifier are practically the same.

The process of epoxidation of ARGOF-3 with a low molecular weight epoxy resin with a degree of polycondensation n = (0-2) in the melt is carried out by combining them in a mass ratio of 1: (3-5), respectively, so that the ratio of the epoxy and hydroxyl groups is eimolecular, then the reaction mixture they are heated up to (120-125) ° С and kept at a temperature of no more than 165 ° С until the content of eposide groups (10.1-11.0) wt.%, the enamel base is dissolved in the usual way, so that its concentration is 50 -60 wt.%, Which is necessary to obtain a prefabricated enamel in accordance with its recipe.

Table 2 shows the various formulations of semi-finished enamel.

Preparation of prefabricated enamel.

The calculated amount of the ARGOF-3E epoxy resin-base solution with a concentration of 50-60% w / w is loaded into a clean ball mill. according to the dry residue, depending on the viscosity, then pigments and a mixture of fillers-microtalc, kaolin and micromica are loaded, and aerosil is last loaded. After loading all the components, close the ball mill cover and turn on the rotary device. The milling process is carried out until a grinding degree of not more than 40 microns is achieved - usually (10-24) hours, depending on the dispersion of the fillers. After that, the contents of the ball mill are poured into the mixer. Mixing the contents in the mixer (dissolver) is continued until the end of the manufacture of prefabricated enamel.

The calculated amount of xylene and ethyl cellosolve, listed in Table 2, is introduced into the mixer and mixing of the contents of the mixer is continued (3-5) hours, after which a sample is taken to determine the viscosity and mass fraction of non-volatile substances and their values are entered into the passport for this batch of enamel prefabricated.

Semi-finished enamel is filtered off and poured into metal containers of (2 ÷ 56) kg.

Prefabricated enamel ARGOF-EP is also obtained on the basis of ARGOF-3 epoxidized with dian resin from alkylated resorcinol - it differs somewhat in color and slightly viscosity, in other properties for enamels they are similar.

Enamel preparation and coating

Before applying coatings, a hardener and, if necessary, an accelerator are added to the enamel prefabricated and the enamel is thoroughly mixed for application onto the surface with a brush, roller, spray, transfer method.

Table 3 shows the load of hardeners in wt. parts per 100 wt. parts of prefabricated enamel.

Properties and operating conditions of enamel coatings.

Table 4 shows the characteristics of the proposed enamel.

The table shows that the proposed enamel exceeds the known atmospheric resistance (enamel EP 525 has a limited atmospheric resistance), resistance to the action of a 3% solution of NaCl in water. The proposed enamel does not require preliminary application of the primer to the surface to be protected, the ARGOF-EP enamel coating for metal resists without changes in appearance for five months to the action of hydrochloric acid with a density of 1.19 g / cm ³ . The metal coating withstands a 25 wt.% Aqueous solution of NaOH and H ₂ SO ₄ even when heated to 80 ° C, benzene when heated to 80 ° C, while protecting the brick, the coating withstands 20% NaOH and 25% HCl solutions at 20 ° C for 1440 hours, and 10% NaCl at 100 ° C for 7 hours without changing the appearance of the samples.

The enamel ARGOF-EP withstands the tests for radiation resistance and deactivability with three cycles of alternating exposure to β-radiation with a density (2681 ÷ 5118) ppm · cm ² (according to GOST 51102-97); and 5 wt.% aqueous NaOH solution at (55 ± 5) ° C for 10 hours; 5 wt.% Aqueous HNO ₃ solution at (55 ± 5) ° С - 10 hours; deactivating formulations at (25 ± 5) ° С - 20 hours and at (65 ± 5) ° С - 8 hours; water at (60 ± 5) ° С - 15 hours; ionizing radiation with a dose of 100 Mrad; temperature action (70 ± 5) ° C for 200 hours.

At the same time, the average deactivation coefficient after three cycles of ¹⁴⁴ Ce and ¹³⁷ Cs corresponds to the standards, and ARGOF-EP enamel is recommended for use at nuclear facilities and the nuclear industry.

The gray and dark gray enamel ARGOF-EP-E (electrical) can withstand temperatures of 180 ° C for 24 hours without any changes, and the breakdown voltage of the enamel is more than 35 kV / mm at 180 ° C and more than 15 kV / mm after exposure (93 ± 2)% rel. humidity at 23 ° C for 48 hours. Surface electrical resistance - 6.2 · 10 ¹² Ohm · cm, after exposure to wet heat - 1.2 · 10 ¹⁰ Ohm · cm.

Enamel with a thickness of 250 μm, deposited on a metal and cured at (20 ± 2) ° C for 72 hours, withstood the effects of gasoline and mineral oils for an unlimited time.

In comparison with an enamel specially made from a semi-finished product according to the closest analogue (RF patent for invention 2221816), the enamel according to the proposed technical solution is characterized by higher adhesion, elasticity and hardness under the same coating conditions (see table 4).

table 2 Recipe for semi-finished enamel ARGOF-EP Name of components NTD on material The composition of the enamel,% Red brown black gray Green Orange Svetl Dark RAL 7016 RAL 7046 RAL 7031 RAL 6002 RAL 2009 RAL 2011 Solution of resin ARGOF-E (55 ± 2)% in a mixture of solvents acetone-toluene (3: 1) According to the proposed tech. the decision 56.90 57.46 59.51 55.71 57.46 57.18 59.23 57.13 Red iron oxide pigment TU 6-10-602-86 13.39 Pigment titanium dioxide grade RO-2 GOST 9808-84 3.35 21.35 20.83 1.16 1.12 Crown lead molybdate TU 301-10-0) 5-89 3.35 15.47 3.25 2.86 Crown Lead Lemon GOST 478-80 - - 0.33 0.33 4,5-1 7.62 16.0 3 - Crown Lead Yellow GOST 478-80 2.23 3.38 0.33 0.33 15.46 Technical carbon P-803 GOST 7885-86 0.46 19.15 1.10 2.18 - - - - Phthalocyanine blue 2 memory TU 6-14-195-74 - - 0,03 0,03 - - - Pigmented chromium oxide GOST 2912-79E - - - - 22.54 - - Microtalc GOST 19284-79 4.46 4,51 4.41 4.37 3.38 4.48 4.88 5.60 Kaolin TU 21-25-220-78 4.46 4,51 4.41 4.37 3.38 4.48 4.88 5.60 Micromica TU 21-25-51-80 4.46 4,51 3.31 4.37 2.25 4.48 4.88 5.60 Aerosil 0.56 0.34 - 0.55 0.35 - 0.35 0.34 Xylene GOST 9410-78; GOST 9949-76 3,7 4.17 2.81 3.61 3.12 3,58 3,50 3.56 Ethyl cellosolve GOST 8313-76 2.7 1.97 2.41 3.32 3.02 2.69 1.85 2.73 Total one hundred one hundred one hundred one hundred one hundred one hundred one hundred one hundred

Table 3 Hardeners, accelerators introduced into the prefabricated enamel Name of components NTD on material Red-brown, the shade is not normal. Black Gray Green Orange light. dark RAL 7016 RAL 7046 RAL 7031 RAL 6002 RAL 2009 RAL 2011 Download hardener for 100 mass parts of the semi-finished product ARGOF-EP in wt. parts Hardener No. 1 Geksametilendi min, 50% solution TU 6-10-1263-77 3.6-3.7 3.4 3.6 3.6 3.6 3.6 3.6 4.0 Hardener No. 2 PO-200 TU 6-10-1279-77 28.6 28.0 28, 6 28.6 28.6 28.6 28.6 35, 0 Hardener No. 5 PO-300 TU 6-10-1093-76 20.6 19.5 20.6 20.6 20.6 20.6 20.6 22.6 Diethylene triamine 2,3 2.0 2,3 2.2 2.1 2.1 2,3 3.0 Polyethylene polyamine 2,5 2.2 2,5 2,4 2,3 2,3 2,5 not Spanish

Table 4 Properties of ARGOF-EP enamel and its components in comparison with analogues Name of indicator ARGOF-EP enamel indicator According to the proposed technical solution Enamel index EP-525 GOST-22438-85 Prototype one 2 3 four 5 one. Appointment - weatherproof Limited weatherproof conductive (graphite) Weatherproof Rad. Resistant, Deactivir. - petrol and oil resistant - heat resistant - electrical insulating - chemical resistant - radiation resistant
deactivable 2. Enamel base indicators 2.1 Appearance Red brown resin Light yellow to dark brown resin Red brown resin 2.2 Melting point, ° С 65-85 There is no data 55-75 2.3 The viscosity of a 50 wt.% Solution in acetone and toluene in a ratio of 3 to 1 (according to VZ-4), s Resorcinol 15-20 Alkylresorcinol 15-20 There is no data 15-20
15-20 2.4 Mass content of epoxy groups,% (without solvent) Resorcinol 10.1-11 Alkylresorcinol 10.8-11 There is no data 7.0-8.0 7.0-8.0 2.5 The degree of curing of the enamel base, with hardener No. 1 (20 ° C - 72 hours) by extraction in boiling acetone, wt.% On ARGOF-E films Resorcinol 95-97 92-95 95-97 Alkylresorcinol 95-97 95-97 3. Prefabricated Indices 3.1 Appearance Movable suspension, standard color Movable suspension, standard color The move. susp. Color by Stage. 3.2 VZ-246 viscosity viscosity with a nozzle diameter of 4 mm at a temperature of (20 ± 0.5) ° С, s 15-35 33-60 16-30 3.3 Mass fraction of nonvolatile substances,% 50-60 56-70 70 +/- 5 3.4 The degree of milling microns, not more 40 40-45 40 3.5 Drying time to degree 3, h, no more 24 24 24 at a temperature of (20 ± 2) ° С with hardener No. 1 72 (full strength) at a temperature of (100 ± 2) ° С with hardener No. 1 one 2 one four. Prefabricated shelf life and conditions 4.1 In hermetically sealed metal containers at a temperature of from -35 to + 35 ° С, months, at least 12 12 12 5. Enamel Properties 5.1 Application Scheme Without primers With primer Without soil. 5.2 Number of layers Not less than 1 There is no data Not less than 1 5.3 Coating hardness, conventional units, no less than according to a pendulum device of type M-3 0.55 0.4-0.5 0.5 5.4 Impact strength on a device of type U-1, cm, not less than fifty fifty fifty 5.5 Film elasticity in bending, mm, not more than 2 3 3 5.6 Static resistance 3% NaCl solution at (20 ± 2) ° С, h, not less than; 48 24 48 hot water at (95 ± 5) ° С, h, not less than 6 there is no data 6 5.7 Adhesion, score, no more one one 2 5.8 The shelf life of enamel after mixing the components at a temperature of (20 ± 2) ° C, h, at least 6 8 6 6. Enamel performance and maintainability If the old paintwork is damaged (since it does not require a primer), enamel can be applied to any paintwork, except nitrocellulose There is no data There is no data

Claims (8)

1. Enamel for coating, which is a kit comprising a semi-finished enamel containing a solution of an epoxy base resin in an organic solvent and an amine type hardener, where the base epoxy resin is obtained by epoxidizing aromatically conjugated hydroxyphenylene having a polycondensation degree n = 0-2 obtained from diatomic phenol or alkylresorcinol, characterized in that the semi-finished product contains a 50-60 wt.% solution of epoxy Dianova resin-base with a degree of polycondensation n = 0-2, epoxidation of hyd oxyphenylene, is carried out in a melt at a temperature of 120-165 ° C in the presence of 0.15-0.35 wt.% 2,4,6-trisdimethylaminomethylphenol to an epoxy content of 10.1-11.0 wt.% and additionally enamel prefabricated pigments, filler - a mixture of microtalc, kaolin and micromica, an organic solvent in the following ratio of ingredients in the enamel semi-finished product, wt.%: Pigments 17-30 The above filler 7-15 Organic solvent 5.22-6.93 The above epoxy solution rest and the ratio of ingredients in the enamel is, parts by weight: The above semi-finished enamel one hundred Amine hardener 2.1-28.6 2. The enamel according to claim 1, characterized in that the pigment in the semi-finished enamel contains red iron oxide pigment and / or titanium dioxide and / or crown lead molybdate and / or lead lemon and / or crown yellow lead and / or carbon, and / or phthalocyanine blue, and / or chromium oxide pigment. 3. The enamel according to claim 1 or 2, characterized in that the semi-finished enamel further comprises an aerosil filler. 4. The enamel according to claim 1, characterized in that the solution of the epoxy resin base in the semi-finished enamel contains a mixture of organic solvents - acetone and toluene in a ratio of 3: 1. 5. The enamel according to claim 1, characterized in that the semi-finished enamel as an organic solvent contains xylene and ethyl cellosolve in an amount providing the desired viscosity of the semi-finished enamel. 6. The enamel according to claim 1, characterized in that as the hardener of the amine type, it contains 50 wt. a solution of hexamethylenediamine in methylcarbinol in an amount of 3.4-4.0 parts by weight 7. The enamel according to claim 1, characterized in that as the hardener of the amine type it contains a low molecular weight polyamide with an amine number from 140 to 300 in an amount of 19.5-35 wt.h. 8. The enamel according to claim 1, characterized in that as an amine type hardener it contains 2.0-3.0 parts by weight. polyethylene polyamine or diethylene triamine.