RU2313550C1 - Flame-proof blistering paint - Google Patents

Abstract

FIELD: protection of metalwork against corrosion and against fire in force-major situation.

SUBSTANCE: proposed paint contains polymer binder of styrene-acryl dispersion, solvent - water, blistering additive of mixture of pentaerythritol, ammonium phosphate and expanded graphite at the following ratio of components (10.0-19.0) : (18.0-32.0) : (5.0-15.0) and additionally paint contains anticorrosive additive in form of mixture of guandine phosphate and guandine chromate at ratio of 100:1.5.

EFFECT: enhanced resistance to electrolytes at retained high flame resistance.

2 tbl

Description

The invention relates to fire-retardant paints and varnishes intended for protection against corrosion and in extreme force majeure circumstances from the action of fire of metal structures, and can be used in construction, transport, oil and gas, petrochemical and chemical industries and other industries where protection of metal structures from corrosion is required and fire.

Known fire retardant intumescent paint, protected by RF patent No. 2174527 class. C09D 5/18, 131/04, 133/00, publ. 2001.10.10. Fire-retardant paint is an aqueous dispersion based on an acrylic dispersion or a mixture thereof with a homo- or copolymer dispersion of vinyl acetate and contains, as intumescent additives, a mixture of ammonium pentaerythritol and polyphosphate at a ratio of 1: 1.3-2.6, respectively, as well as anionic and / or an inactive surfactant, antifoam, cellulose ether quencher, preservative, titanium dioxide, talc or microtalc, possibly sodium tetraborate and water at certain ratios of these components. A disadvantage of the known composition is that fire-retardant paint is used only for internal work due to the low resistance to weathering (rain, snow, etc.), a low degree of expansion and, as a result, insufficient fire resistance, as well as a small temperature range of expansion of the paint.

Closest to the claimed technical essence and the achieved result, selected as a prototype, is fire-retardant intumescent paint (RF patent No. 2244727 class C1, C09D 5/18, 125/08, 125/10, 127/24, 131/04, 183/04, 5/02, publ. 20.01 / 2005 Bull. No. 2) containing a polymer binder - styrene-acrylic dispersion, a solvent and an intumescent additive based on pentaerythritol and ammonium polyphosphate, additionally containing expanded graphite in the composition of the intumescent additive in the following ratio components,%:

polymer binder - 25.0-42.0 pentaerythritol - 10.0-19.0 ammonium polyphosphate - 18.0-32.0 expanded graphite - 5.0-15.0 solvent - the rest

The quantitative ratio of pentaerythritol and ammonium polyphosphate is 1: 1.3-2.6, respectively.

In the paint, polymer dispersions, for example styrene-acrylic, polyvinyl acetate or styrene-butadiene dispersions, perchlorovinyl or organosilicon varnish, were used as the polymer binder.

The paint may additionally contain flame retardants, for example water glass, pigments, for example titanium dioxide, surfactants, stabilizers and plasticizers in an amount not exceeding 10% by weight of the composition.

The disadvantages of the prototype include insufficiently high chemical resistance under the action of aqueous electrolytes, saline water, solutions of salts, acids and bases, typical for industrial and building metal structures of oil and gas, petrochemical, chemical and other industries.

The problem solved by the invention is to increase the properties of the action of electrolytes while maintaining high fire resistance.

This result is achieved in that the fire retardant intumescent paint, consisting of a polymeric binder, solvent, intumescent additive based on pentaerythritol and ammonium polyphosphate containing expanded graphite, according to the invention additionally contains an anti-corrosion additive in the following ratio, wt.%:

polymer binder 25.0-30.0 intumescent additive 50.0-68.0 anticorrosive additive 0.8-1.0 solvent rest

In the paint according to the invention, a styrene-acrylic dispersion is used as a polymer binder.

The intumescent additive contains pentaerythritol, ammonium polyphosphate and expanded graphite in the ratio (10.0-19.0) :( 18.0-32.0) :( 5.0-15.0).

The anticorrosion additive is a mixture of guanidine phosphate and guanidine chromate in a ratio of 100: 1.5. This mixture, which is part of the paint coating, when adsorbed by the coating of water from the surrounding space forms passive films on the metal steel surface (bottom of pores and other defects in the coating), which inhibit the corrosion process.

Water is used as a solvent when using styrene-acrylic dispersion. Pigments may be added to the paint composition to give an appropriate color.

Fireproof intumescent paint is made as follows.

An intumescent additive is first prepared. For this purpose, pentaerythritol, ammonium polyphosphate and expanded graphite are rubbed on a paint grater to a homogeneous finely divided mass.

Then guanidine phosphate and guanidine chromate are separately mixed to obtain a homogeneous mass. An aqueous polymer dispersion, an anti-corrosion additive and the resulting intumescent additive are loaded into the mixer. The resulting mixture is stirred for 25-30 minutes. Then water is added to the mixer. The composition is stirred for 1-1.5 hours.

The composition may be applied by brush, roller or spray. The drying of the first layer is carried out for 1.5 hours, the subsequent - 1 hour. Final drying of all coating layers 36 hours.

Example No. 1

14 g of pentaerythritol, 26 g of ammonium polyphosphate and 5 g of expanded graphite are rubbed onto the paint sprayers to a homogeneous finely divided mass. The mixer is loaded with 26 g of an aqueous styrene-acrylic dispersion of the brand "Lacryl" E-21, the resulting homogeneous fine mass and 0.9 g of guanidine chromate and guanidine phosphate in a ratio of 1: 100. The mixture was stirred for 25 minutes. Then water was added to ensure the working viscosity of the solution. The composition was stirred for 1.5 hours.

The fire-retardant properties of the paint composition for metal structures were evaluated by measuring the temperature of the protected surface of the sample after 15 minutes exposure to it with an open flame with a temperature of 900-1000 ° C. The flame was created by a gas burner, the nozzle of which was located at a distance of 80 mm from the surface of the sample. The temperature of the surface to be protected was measured using a thermocouple paired with a potentiometer.

The anticorrosion properties with respect to carbon steel were evaluated visually after exposure to water and a 3% NaCl solution and separation of the paint film from the steel sample.

Examples No. 2-9 are shown analogously to example 1. Composition 10 corresponds to the prototype.

Table 1
The formulations of the investigated paint compositions Name of components The content of components,% of the mass. one 2 3 four 5 6 7 8 9 10 50% styrene-acrylic dispersion of the brand "Lacryl" E-21 TU 2241-017-50955201-2001 25.0 25.0 25.0 27.5 27.5 27.5 30,0 30,0 30,0 34.0 Ammonium polyphosphate 26.0 26.0 26.0 26.0 26.0 26.0 26.0 26.0 26.0 26.0 Pentaerythritol 14.0 14.0 14.0 14.0 14.0 14.0 14.0 14.0 14.0 14.0 Expanded graphite 5,0 5,0 5,0 10.0 10.0 10.0 15.0 15.0 15.0 10.0 Guanidine Chromate 0.008 0.009 0.01 0.008 0.009 0.01 0.008 0.009 0.01 - Guanidine phosphate 0.84 0.9 0.96 0.84 0.9 0.96 0.84 0.9 0.96 - Water 29,152 29,091 29.03 21,652 21,591 21.53 14,152 14,091 14.03 16,0

The table shows that the proposed paint in comparison with the prototype has increased anti-corrosion properties and can be used in oil and gas and other industries as anti-corrosion and in force majeure circumstances as fire retardant intumescent paint.

table 2
The results of the experiments Composition number Degree of expansion Temperature on the back of the sample after 15 minutes of fire exposure, ° C Expansion temperature range, ° С The presence of corrosion foci after exposure in water after 30 days The presence of corrosion foci after exposure to 3% NaCl after 30 days. one 2 3 four 5 6 one 2080 151 250-700 Individual corrosion points 5-7% - surfaces Individual corrosion points 7-9% of the surface 2 2230 138 250-700 Clean metal Individual corrosion points 3-5% of the surface 3 2290 132 250-700 Clean metal Individual corrosion points 2-3% of the surface four 2160 140 250-700 Individual corrosion points 5-7% of the surface Individual corrosion points 7-11% of the surface 5 2310 116 250-700 Clean metal Individual corrosion points 3-5% of the surface 6 2390 112 250-700 Clean metal Individual corrosion points 2-3% of the surface 7 2410 108 250-700 Individual corrosion points 5-7% of the surface Individual corrosion points 5-7% of the surface 8 2450 one hundred 250-700 Clean metal Individual corrosion points 3-5% of the surface 9 2300 one hundred 250-700 Clean metal Individual corrosion points 2-3% of the surface 10 2480 one hundred 250-700 Continuous corrosion - 100% of the surface Pitting - 100% of the surface

Claims (1)

Fire-retardant intumescent paint, including a polymer binder styrene-acrylic dispersion, a solvent of water and an intumescent additive, a mixture of pentaerythritol, ammonium polyphosphate and expanded graphite in the ratio (10.0-19.0) :( 18.0-32.0) :( 5 , 0-15.0), characterized in that it further comprises an anticorrosive additive, which is a mixture of guanidine phosphate and guanidine chromate in a ratio of 100: 1.5 in the following ratio of components wt.%: polymer binder - styrene-acrylic dispersion 25.0-30.0 intumescent additive - a mixture of pentaerythritol, ammonium polyphosphate and expanded graphite in the ratio (10.0-19.0) :( 18.0-32.0) :( 5.0-15.0) 50.0-68.0 anticorrosive additive 0.8-1.0 solvent - water rest