RU2731599C1 - Method of producing microencapsulated thermo-activated extinguishing agent - Google Patents

Abstract

FIELD: fire-fighting equipment.

SUBSTANCE: invention relates to means of extinguishing fires in different volumes, specifically to a method of producing a microencapsulated thermoactivated extinguishing agent (hereinafter microcapsules) of a spherical shape of a given diameter and a stabilized activation temperature. Object of this invention is development of new microencapsulated thermoactivated agent in form of monotonous mononuclear microcapsules of spherical shape, specified diameter, thickness of shell, mass and temperature of pulse release of agent, as well as a novel method of producing microcapsules and fire extinguishing articles based thereon. Set task has been solved by developing a method of producing described microencapsulated heat-activated extinguishing agent, which consists in the fact that microcapsules are formed by injection-drop injection under pressure of heated extinguishing agent into the medium of cooled film-forming agent, placed under conditions of low pressure, for this purpose, components are mixed in reactor for preparation of concentrate of film-forming agent, obtained mixture is cooled at low pressure in reactor, then mixed and re-cooled to temperature required for formation of stabilized colloidal condition of film-forming agent concentrate, wherein the extinguishing agent is placed in the tank of the apparatus, the pressure required to remove the air bubbles is created, and with constant stirring, the agent is heated to a certain temperature depending on the preset microcapsule activation temperature, then the heated agent under pressure is supplied to the nozzles unit and the drops are injected into the reactor into the medium of the cooled film-forming concentrate for a certain period of time at the engine shaft rotation speed depending on the preset external diameter of the ready microcapsules, wherein each heated drop, falling in the medium of the film-forming agent concentrate, which is in the reactor at low pressure, expands and forms the primary sphere of the microcapsule nucleus, which becomes the center of activation of the process of hardening (polymerisation) of the film-forming agent, cooling microcapsule nucleus in the low-temperature medium of the reactor is actively compressed, uniformly compacted and creates after hardening a strong microcapsule with a spherical monolithic shell, after the injection cycle, the formed microcapsules are drained, filtered and dried at room temperature. According to the invention, it is desirable that in the reactor the film-forming agent concentrate is cooled to temperature of +10 - +15 °C at pressure of 0.1–0.5 Atm, then mixed and re-cooled to temperature of +8 - +18 °C. According to the invention it is desirable that the agent placed into the tank of the injection plant is heated to a temperature of +35 - +95 °C, then, under pressure of 2.0–4.0 atm, is fed into the medium of the cooled film-forming agent concentrate for not more than 20–30 minutes at the engine shaft rpm of 1500–2500 rpm. Additionally, it is desirable to use as a film-forming agent concentrate a mixture of epoxy resin, diethylene glycol and maleic anhydride, or a mixture of water, gelatine and sodium sulphate, or a mixture of water, polyvinyl alcohol and methanol. Besides, it is desirable to use dibromomethane, or perfluoroketone, or freon 114B2 as a fire extinguishing liquid. According to the invention, the microcapsules have an outer diameter in range of 50–1100 mcm, and the shell weight is 4–10 % of the weight of the microcapsule, and in one batch, not less than 90 % of microcapsules having homogeneous physicochemical indices are obtained.

EFFECT: technical result consists in improvement of efficiency of fire extinguishing in various local volumes and is achieved by maintaining physicochemical characteristics of the agent and uniformity of activation parameters by creating a homogeneous monolithic shell of microcapsules with given thickness.

12 cl, 3 tbl

Description

Technology area

The group of inventions relates to means of extinguishing fires in various volumes, namely to a microencapsulated thermally activated extinguishing agent, a method for producing a microencapsulated thermally activated extinguishing agent (hereinafter referred to as microcapsules) with a spherical shape of a given diameter and a stabilized activation temperature, as well as fire extinguishing products based on the mentioned microencapsulation.

The inventions can be used to suppress fires at a chemical level in various volumes, such as sockets, switches, switch boxes, distribution boards, electrical cabinets, cabinets and control panels, safes, valuables, boxes for chemical and explosive products, server racks, fuel tanks , block-modular fuel storages, engine compartment, engine compartments, inter-wall and inter-bulkhead spaces, cable ducts and other objects with a degree of protection IP20 and higher.

Prior art

Today, the problem of microencapsulation of various target products with the creation of a microcapsule, the shell of which provides the release of the target product under certain parameters of external influences, leading to rupture of the shell, is very urgent. The most difficult task is to microencapsulate the target products, which are highly volatile substances, since it is necessary to create a homogeneous monolithic shell that has high strength and low permeability when heated and at the same time ensures its destruction or opening at a given temperature, which is necessary to ensure the most efficient use of the contained in microcapsule of the target product.

The principle of operation of the microcapsule is based on a pulsed (explosive and / or shock) release of a thermo-extinguishing agent (hereinafter referred to as agent) encapsulated in the microcapsule core into the active combustion zone when the activation temperature is reached and / or exceeded in the protected volume.

This method of delivery of the agent makes it possible to most effectively extinguish fires not only when placing microcapsules over the source of possible fire (due to natural deposition of the agent), but practically from any side of an open flame combustion or other source of high temperature, since the release of the agent due to the uniformity and solidity of the shell , mainly, will be carried out in the direction with the temperature closest to the activation temperature.

The released agent begins to actively displace oxygen from the fire zone, interact with buffer (free) hydrogen, which is a key link in the combustion process, and release halogen (retractor) with the formation of “heavy” free radicals. Kinetic chains at the chemical level of combustion are broken and the column of flame is destroyed (defragmented), sharply reducing the temperature and knocking down the chains of decomposition processes. Due to the active drop in temperature, the condensation process starts, the decomposition chains of substances are stopped (inhibited) and the fire is extinguished.

It is known that fire extinguishing products have been created on the basis of microcapsules for fire extinguishing. The products are made in the form of fire-extinguishing plates, tapes, pastes, paints, foams and can be used for stand-alone operation or used in conjunction with technical means (sensors and detectors), which allow informing the fire brigade about an actuation, and can also be integrated with elements of forced activation as part of automatic fire extinguishing systems.

The prior art knows microencapsulated extinguishing agents, methods for producing microencapsulated extinguishing agents, as well as the use of microencapsulated extinguishing agents as extinguishing agents, for example, patents RU 2631868, B01J 13/02, publ. 09/27/2017, Bul. No. 27, RU 2631867, publ. 09/27/2017, Bul. No. 27, application PCT / RU 2016/000528, RU 2559480, A62D 1/00 publ. 08/10/2015 Bul. No. 22.

Known patent RU 2616940, A62C 2/00, A62D 1/08 publ. 04/18/2017, Bul. No. 11, which describes a polymer composition for the manufacture of thermally activated fire extinguishing materials, containing an aqueous dispersion of the polymer as a binder, a mineral filler, a fibrous material and a microencapsulated fire extinguishing agent, including in each microcapsule a polymer shell and a core containing a carrier gas as components, having boiling point from -155 to + 10 ° С, combustion phlegmatizer and combustion inhibitor in mass ratio: carrier gas 5-50%, combustion phlegmatizer 30-70%, combustion inhibitor 1-25%. The disadvantages of the known method include the fact that with the selected production method, it is practically impossible to ensure accurate dosing of these components to each microcapsule. Cycles of heating, cooling, adding precipitants, etc. under conditions of constant stirring during the production process are guaranteed to cause stratification of the mixed agent, which will lead to a scatter of activation temperatures, inhomogeneous concentration of components and, as a consequence, to a decrease in fire extinguishing efficiency.

Known patent RU 2628375, A62C 2/00, A62D 1/08, publ. 08/16/2017 Bul. No. 23, which describes a microencapsulated fire extinguishing agent, including in each microcapsule a polymer shell and a core containing, as components, a carrier gas having a boiling point from -155 ° C to + 10 ° C, a combustion phlegmatizer and a combustion inhibitor in a mass ratio: carrier gas 5-50%, combustion phlegmatizer 30-70%, flame retardant 1-25%. The patent specification describes a method for producing microcapsules. The disadvantages of this method include the fact that with the described method there is no possibility of forming a homogeneous monolithic polymer shell with stable characteristics. In most cases, polymer casings, crosslinked without stabilization, have many latent defects that appear immediately after vulcanization. Such microcapsules have a short shelf life before the active loss of the agent begins: from 20% to 50% of the core mass in the first 10 days after production. Microcapsules with an unstabilized polymer shell cannot be sold as raw materials and / or a component of mixed products such as fire-extinguishing paints and are only suitable for the manufacture of fire-extinguishing plates with a service life of no more than one year.

Known patent RU 2469761, A62D 1/00, publ. 12/20/2012, Bul. No. 35 microencapsulated extinguishing agent, which contains a polymeric shell and a core of extinguishing liquid such as perfluoroethyl perfluoroisopropyl ketone or dibromomethane, or mixtures with other bromofluorinated fluids. The invention discloses a method for producing a microencapsulated extinguishing agent, extinguishing composite materials, for example, made in the form of pastes, plates, films, articles, hard foams, fabrics, and a fire extinguishing coating containing the said microencapsulated extinguishing agent. To ensure the stability of microcapsules containing perfluoroethyl-perfluoroisopropyl ketone as a core, enclosed in a shell of resorcinol urea-formaldehyde resin, it was proposed to introduce nanosized montmorillonite plates into the shells of microcapsules. The disadvantages of this method include the fact that a separate stage of preparation of montmorillonite, not only complicates the process of microencapsulation, but also makes it more expensive. In addition, despite the fact that it was possible to somewhat slow down the loss of the nucleus from the microcapsules, in practice their stability remained insufficient.

Known patent RU 2631866, B01J 9/34, 13/02, publ. 09/27/2017 Bul. No. 27 "Method for producing fire extinguishing microcapsules and fire extinguishing microcapsule", which describes a method for producing (options) fire extinguishing microcapsules containing a fire extinguishing agent and a polymer shell, which includes the stages of emulsifying a fire extinguishing agent - perfluorine (ethyl isopropyl ketone) in a solution of polyvinyl alcohol and adding polymer solution - reactive melamine-formaldehyde resin, followed by the addition of acid with vigorous stirring in 450-500 ml of water at 40-45 ° C for 7-15 minutes to isolate the coacervate phase with the formation of a polymer liquid-viscous wall on the surface of the capsules, followed by post-condensation for 110-130 minutes with stirring, with further heating, leading to the formation of a solid wall of the capsule with a fire-extinguishing agent, characterized by the ability of an explosive opening in the temperature range of 90-110 ° C, after which the capsules are washed with distilled water and dried, and the capsule wall can be multilayer.

It should be noted that the main disadvantage of the known methods using the coacervation method is that the methods are quite laborious and time-consuming, include many complex technological cycles, depending on the quality of mixing, temperature conditions, the uniformity of the pH level, the rate of the crosslinking reaction of the film former, the presence of side effects. reactions and other wide range of factors. In addition, a significant disadvantage of microencapsulation using the coacervation method is the inability to avoid agglomeration and / or gelation of a part of the encapsulated substance, which leads to the formation of multinuclear and / or matrix microcapsules with low fire extinguishing efficiency due to an increase in heat resistance, as well as a decrease in the rate and amount of the released agent.

Microcapsules obtained by the coacervation method have several disadvantages:

- a wide range of indicators of heterogeneity, degree of curing and thickness of the shell,

- the different dimensions of the outer diameters of microcapsules in one batch, that is, the content in one batch of microcapsules with a range of sizes of outer diameters from 0.1 mm to 2.0 mm,

- the spread of indicators of the activation temperature of microcapsules of one batch in a wide range from + 80C to + 250 ° C,

- the presence of destructive changes in the physicochemical properties of the agent due to the use of prolonged (many hours) exposure to high temperatures mixed with other substances and components,

- inhomogeneity and viscosity of the core up to a gel-like state,

- the presence of impurities in the core of the products of intermediate reactions.

Disclosure of invention

The objective of the present invention is to develop a new microencapsulated thermoactivated agent in the form of uniform mononuclear microcapsules of a spherical shape, a given diameter, shell thickness, mass and temperature of the pulsed release of the agent, as well as a new method for producing microcapsules and fire-extinguishing products based on them.

The technical result consists in increasing the efficiency of extinguishing fires in various local volumes and is achieved by maintaining the physicochemical characteristics of the agent and the homogeneity of the activation parameters by creating a uniform monolithic shell of microcapsules with a given thickness.

The combined principle of action of thermally activated microcapsules consists in the following one-time effects on a fire, which together lead to the creation of an environment that does not support combustion: displacement of oxygen, binding of buffer (free) hydrogen, release of halogens with the formation of "heavy" free radicals, destruction (defragmentation) of the flame column , knocking down the temperature, stopping the decomposition of substances and starting the condensation process.

The problem was solved by creating a microencapsulated thermoactivated extinguishing agent containing microcapsules having a core of extinguishing agent and a spherical polymer shell, which is uniform and homogeneous, has the ability of explosion-like destruction in the temperature range 90 ° C - 150 ° C, while the outer diameter of the shell is in the range of 50 microns - 1100 microns, and the shell mass is 4-10% of the microcapsule mass.

In this case, according to the invention, the polymer shell material is a concentrate of a film-former in the form of a mixture of epoxy resin, diethylene glycol and maleic anhydride or a mixture of water, gelatin and sodium sulfate or a mixture of water, polyvinyl alcohol and methanol.

Moreover, according to the invention, the microcapsule core contains dibromomethane or perfluoroketone or freon 114B2.

The task was also solved by the development of a method for obtaining the above-described microencapsulated thermally activated extinguishing agent, which consists in the fact that the microcapsules are formed by injection-drop injection under pressure of a heated extinguishing agent into the environment of a cooled film former placed under reduced pressure, for which the components are mixed in the reactor for preparation of the film former concentrate, the resulting mixture is cooled under reduced pressure in the reactor, then stirred and recooled to the temperature required for the formation of a stabilized colloidal state of the film former concentrate, while a fire extinguishing agent is placed in the tank of the installation, the pressure required to remove air bubbles is created, and with constant stirring, the agent is heated to a certain temperature, depending on the set activation temperature of the finished microcapsules, then the heated agent under pressure is fed into the nozzle block, and injected drops into the reactor into the medium of the cooled film-former concentrate for a certain time at the speed of rotation of the motor shaft, depending on the given outer diameter of the finished microcapsules, and each heated drop, getting into the medium of the film-former concentrate, which is in the reactor at a reduced pressure, expands and forms the primary sphere of the nucleus microcapsules, which is the center of activation of the curing (polymerization) process of the film former, the cooling nucleus of the microcapsule nucleus in the low-temperature environment of the reactor is actively compressed, uniformly compacted and after curing creates a strong microcapsule with a spherical monolithic shell, at the end of the injection cycle the formed microcapsules are poured and drained from room temperature.

In this case, according to the invention, it is desirable that the concentrate of the film former in the reactor be cooled to a temperature of + 10 ° C - + 15 ° C at a pressure of 0.1-0.5 Atm, then stirred and recooled to a temperature of + 8 ° C - + 18 ° C.

At the same time, according to the invention, it is desirable that the agent placed in the tank of the injection unit is heated to a temperature of + 35 ° C - + 95 °, then under a pressure of 2.0 - 4.0 Atm it is fed into the medium of the cooled concentrate of the film-former for no more than 20 -30 min at a speed of rotation of the engine shaft 1500-2500 rpm.

In addition, it is desirable to use a mixture of epoxy resin, diethylene glycol and maleic anhydride or a mixture of water, gelatin and sodium sulfate or a mixture of water, polyvinyl alcohol and methanol as the concentrate of the film former.

In addition, it is desirable to use dibromomethane or perfluoroketone or freon 114B2 as the extinguishing liquid.

Moreover, according to the invention, the microcapsules have an outer diameter in the range of 50 μm - 1100 μm, and the shell mass is 4-10% of the microcapsule mass, and at least 90% of microcapsules having uniform physicochemical characteristics are obtained in one batch.

The problem was also solved by creating a fire-extinguishing coating of paint, a fire-extinguishing plate, a fire-extinguishing cape containing the above-mentioned microencapsulated extinguishing agent.

The invention is further explained by the description of a microencapsulated extinguishing agent, the implementation of the method for its production, extinguishing materials and paint with its use, which do not go beyond the scope of patent claims and do not limit the possibilities of carrying out the invention.

Implementation of the invention

For the production of microcapsules, it is proposed to use the method of injection-drop injection under pressure of a heated agent into the environment of a cooled concentrate of a film-forming agent under reduced pressure and stabilized colloidal state.

The method for producing microcapsules contains the following sequence of operations: - using an asynchronous motor, the rotation speed of which is regulated by a frequency converter in a given speed range, the camshaft is driven into rotation, which by short-term pressure on the needle valves injects droplet portions of the agent (hereinafter drops) into the concentrate film former;

- each heated drop in a low-pressure environment instantly expands and forms a primary sphere (microcapsule embryo), which becomes the center of activation of the curing (polymerization) process of the film former, since heat, abnormal for the reactor environment, becomes a catalyst for the active formation of a microcapsule shell from colloidal particles;

- the cooling core of the microcapsule embryo in the low-temperature medium of the reactor is actively compressed, evenly densifying and after curing, creating a strong microcapsule with a uniform (monolithic) shell.

As a film former, available and inexpensive substances are used, which, after curing, create a solid, uniform shell of microcapsules that best meets the requirements of a pulsed (explosive and / or shock) release of a fire extinguishing agent - gelatin, polyvinyl alcohol, epoxy resin mixed with diluents and / or solvents and curing catalysts.

The extinguishing thermoactivated agent encapsulated in the microcapsule core can be selected from the range of dibromomethane, perfluoroketone, freon 114B2, and can also be in the form of a multicomponent mixture containing a carrier gas (transport gas), a phlegmatizer (retarder), a combustion inhibitor and other substances.

This production method allows:

- to establish large-scale, practically waste-free, production of uniform mononuclear microcapsules of a spherical shape, a given shell thickness, as well as the required diameter, for example, in the range from 50 microns to 1100 microns, depending on the specified requirements;

- to obtain batches in which microcapsules have the same properties of explosive destruction of microcapsules at a given activation temperature, for example: + 100 ° С (+/- 5 ° С), + 120 ° С (+/- 5 ° С), + 140 ° С (+/- 5 ° С) or other temperature in the range from + 90 ° С to + 150 ° С, depending on the specified requirements;

- to use available, inexpensive and non-toxic substances as a film-former, which after curing create a solid uniform shell of microcapsules;

- to encapsulate effective and available agents selected from the range: dibromomethane or perfluoroketone (commercial name: Novec-1230) or Freon 114B2 or mixed (multicomponent) agents containing a carrier gas (transport gas), phlegmatizer (retragrant), flame retardant and others substances;

- to exclude the use in the process of microencapsulation of prolonged (many hours) exposure to high temperatures, as well as mixing with other substances, leading to changes in the structure and properties of the agent and film-forming agent;

- to reduce the number and duration of technological cycles.

Equipment for the production of microcapsules by the injection-drop injection method consists of a reactor and an injection unit. The reactor consists of a chiller, a sealed heat-insulated vessel, a vacuum pump, a pressure control valve, a magnetic stirrer and a kingston for draining the reaction mixture into the process vessel. The injection unit consists of a hermetically insulated tank, a vacuum pump, a heater, a temperature controller, a magnetic stirrer, a high-pressure pump, a pressure control valve, an asynchronous electric motor, a frequency converter, a manifold, a camshaft, needle valves and a block of nozzles with silicone nozzles with a diameter of not more than 50 microns ...

The main advantages of the method:

- the ability to accurately adjust the characteristics of microcapsules by the outer diameter, shell thickness and activation temperature, by controlling the temperature of the agent, the composition of the film-forming concentrate, the pressure inside the reactor and the injection unit, as well as the speed of rotation of the asynchronous motor;

- the possibility of stabilizing the colloidal state of the film-former concentrate by maintaining a given level of pressure and temperature inside the reactor under conditions of a constantly increasing volume of substances contained;

- the filtered concentrate of the film-former can be stored for no more than 3 days in a refrigerator at a temperature of no more than + 5 ° C and used for the production of the following portions of microcapsules.

Examples of specific implementation of the invention

Example # 1.

Production cycle of microcapsules with an epoxy resin shell:

1) The reactor is filled with 30-40% epoxy resin (with a content of epoxy groups of at least 21%), heated to + 25 ° C - + 30 ° C, and 30-40% of an active diluent of diethylene glycol at room temperature.

2) The mixture is stirred for 10-15 minutes using a magnetic stirrer and cooled by a chiller to a temperature of + 10 ° C - + 15 ° C.

3) 5-15% maleic anhydride is poured into the reactor with constant stirring in small portions and the air is pumped out using a vacuum pump to a pressure of 0.1-0.5 atm.

4) A mixture of epoxy resin, diethylene glycol and maleic anhydride (hereinafter the concentrate of the film former) is stirred under reduced pressure for 10-15 minutes using a magnetic stirrer and cooled by a chiller to a temperature of + 8 ° C - + 18 ° C, borderline at a given concentration of components to start the gelation process and reverse transition to the liquid phase (colloidal state).

5) 20-30% of dibromomethane or perfluoroketone or freon 114B2 is poured into the tank of the injection unit and a reduced pressure is created using a vacuum pump to remove air bubbles.

6) The agent is heated for 5-10 minutes with constant stirring to a temperature of + 35 ° C - + 95 ° C, depending on the required activation temperature of the finished microcapsules.

7) By means of a high-pressure pump, an agent under a pressure of 2-4 atm is supplied to the manifold and the nozzle block.

8) The cycle of injection of drops into the reactor is carried out for no more than 20-30 minutes when the asynchronous motor is operating at 1500-2500 rpm, depending on the specified diameter of the finished microcapsules.

9) At the end of the injection cycle, the formed microcapsules in the medium of an unused film-former concentrate (reaction mixture) are poured through a kingston into a process vessel.

10) Then the microcapsules are filtered and dried in a drying chamber at room temperature.

Example # 2.

Production cycle of microcapsules with gelatin shell:

1) 40-50% of water heated to 90 ° C is poured into the reactor, and 25-35% of gelatin is added.

2) The mixture is stirred for 10-15 minutes using a magnetic stirrer and cooled by a chiller to a temperature of + 10 ° C - + 15 ° C.

3) 5-10% sodium sulfate is added in small portions to the reactor with constant stirring and the temperature of the mixture is + 40 ° C - + 50 ° C and air is pumped out to a pressure of 0.1-0.5 atm using a vacuum pump.

4) A mixture of water, gelatin and sodium sulfate (hereinafter referred to as the concentrate of the film former) is stirred under reduced pressure for 10-15 minutes using a magnetic stirrer and cooled by a chiller to a temperature of + 8 ° C - + 18 ° C, borderline at a given concentration of components for starting the gelation process and the reverse transition to the liquid phase (colloidal state).

5) 20-30% of dibromomethane or perfluoroketone or freon 114B2 is poured into the tank of the injection unit and a reduced pressure is created using a vacuum pump to remove air bubbles.

6) The agent is heated for 5-10 minutes with constant stirring to the required temperature of + 35 ° C - + 95 ° C, depending on the required activation temperature of the finished microcapsules.

7) By means of a high-pressure pump, the agent under a pressure of 2-4 atm. are fed to the manifold and the injector block.

8) The cycle of injection of drops into the reactor is carried out for no more than 20-30 minutes when the asynchronous motor is operating at 1500-2500 rpm, depending on the specified diameter of the finished microcapsules.

9) At the end of the injection cycle, the formed microcapsules in the medium of an unused film-former concentrate (reaction mixture) are poured through a kingston into a process vessel.

10) Then the microcapsules are filtered and dried in a drying chamber at room temperature.

Example No. 3.

Production cycle of microcapsules with polyvinyl alcohol shell:

1) 25-35% of water heated to 90 ° C is poured into the reactor, and 15-25% of polyvinyl alcohol is added.

2) The mixture is stirred for 10-15 minutes using a magnetic stirrer and cooled by a chiller to a temperature of + 10 ° C - + 15 ° C.

3) Into the reactor with constant stirring and a mixture temperature of + 40 ° C - + 50 ° C, add 30-40% methanol in small portions and pump out air to a pressure of 0.1-0.5 atm using a vacuum pump.

4) A mixture of water, polyvinyl alcohol and methanol (hereinafter referred to as the film former concentrate) is stirred under reduced pressure for 10-15 minutes using a magnetic stirrer and cooled by a chiller to a temperature of + 8 ° C - + 18 ° C, which is borderline at a given concentration of components for starting the gelation process and the reverse transition to the liquid phase (colloidal state).

5) 20-30% of dibromomethane or perfluoroketone or freon 114B2 is poured into the tank of the injection unit and a reduced pressure is created using a vacuum pump to remove air bubbles.

6) The agent is heated for 5-10 minutes with constant stirring to the required temperature + 35 ° C - + 95 ° C, depending on the set activation temperature of the finished microcapsules.

7) By means of a high-pressure pump, the agent under a pressure of 2-4 atm. are fed to the manifold and the injector block.

8) The cycle of injection of drops into the reactor is carried out for no more than 20-30 minutes when the asynchronous motor is operating at 1500-2500 rpm, depending on the specified diameter of the finished microcapsules.

9) At the end of the injection cycle, the formed microcapsules in the medium of an unused film-former concentrate (reaction mixture) are poured through a kingston into a process vessel.

10) Then the microcapsules are filtered and dried in a drying chamber at room temperature.

Technique for laboratory analysis and fire tests of microcapsules

Samples of batches of microcapsules produced under different technological modes of operation of the installation are tested: for the prevailing diameter, activation temperature, fire extinguishing efficiency.

The results of the analyzes carried out are entered into the flow chart, which allows at the production stage by setting the same operating modes of the installation to set uniformity or control changes to the required characteristics of the produced batches of microcapsules.

Determination of the outer diameter of microcapsules

Samples weighing at least 500 g are taken from batches of microcapsules made from different shell and core materials by random sampling.

Samples of microcapsules are sieved through a laboratory sieve with a mesh pitch of not more than 50 microns to determine the prevailing (predominant) diameter size in one batch. One lot should contain at least 90% of the total amount of microcapsules with the same diameter. This size is considered the prevailing size of the diameter of the microcapsule in one batch.

Conclusion and conclusions.

- The low speed of rotation of the unit allows the production of microcapsules of large diameter due to the injection of bulk droplets of the agent into the medium of the concentrate of the film-forming agent.

- High rotational speed of the unit allows the production of small diameter microcapsules due to the injection of small drops of the agent into the medium of the film-forming concentrate.

- Precise adjustment of the required prevailing diameter of microcapsules in a given mode of the unit speed is carried out by regulating the temperature of the agent.

Determination of the activation temperature of microcapsules

From batches of microcapsules made from different shell and core materials, samples with a mass of at least 30 g are taken by random sampling.

Microcapsule samples are heated on a derivatograph to determine the activation temperature. The percentage of the shell is determined by the weight of the remaining substance after the agent is completely released.

Conclusions and conclusions

An increase in the temperature of the agent during injection leads to the formation of a thicker shell, which increases the heat resistance of the microcapsules and has a higher activation temperature.

Fire tests

The tests are carried out in a well-ventilated room equipped with a supply and exhaust ventilation system, with walls and a ceiling made of non-combustible and / or refractory material.

The equipment for conducting fire tests includes:

- Metal table - 1 pc.

- A metal box with a transparent fire-resistant glass door (L × H × D 25 × 25 × 16 cm) with a volume of 10 liters (hereinafter the box) - 1 pc.

- Model fire source in the form of a metal cup with a diameter of 3 cm and a height of at least 3 cm (hereinafter MOP-3) - 1 pc.

- Metal saucer with a diameter of 10 cm (hereinafter saucer) - 1 pc.

- Gasoline AI-92 - 1 liter.

- Gas burner - 1 pc.

- Stopwatch - 1 pc.

- Laboratory balance - 1 pc.

- Portable thermal imager - 1 pc.

Samples weighing not less than 1.1 g are taken from batches of microcapsules made from different shell and core materials by random sampling. Samples are weighed, visually assessed for quality and uniformity of appearance before and after testing.

Fire test procedure

To ensure the flow of fresh air to the MOP-3, three holes with a diameter of at least 3.5 cm are drilled in the bottom of the box.To ensure the outflow of combustion products, one hole with a diameter of at least 3.5 cm is drilled in the upper right corner of the box.Checking a sample of microcapsules for fire extinguishing

A drawer is placed in the middle of the metal table, a saucer with a microcapsule sample is attached to the top of the drawer. MOP-3 is installed at the bottom of the box. 30 g of IA-92 gasoline are poured into MOP-3. A gas burner is used to initiate a fire. After 5-10 seconds of free burning, the drawer door is closed. The time to extinguish the fire is recorded using a thermal imager.

Conclusions and Conclusions.

The tests are considered successful if the sample of microcapsules successfully extinguishes MOP-3 in the box for the time according to the table, and the mass of the remaining substance corresponds to the mass of the shell of the microcapsules, i.e. full agent release.

Examples of using microcapsules

Example No. 1 Fire extinguishing paints.

Fire-extinguishing paints are designed to create fire-resistant and / or resistant to direct flame effects coatings, as well as to reduce the heating rate of the internal volume of fire-hazardous and hard-to-reach objects, such as cable ducts, wooden boxes for ammunition, electrical cabinet, control panel, canisters, barrels for fuels and lubricants, gas tanks, modular fuel storages, reservoirs, inter-wall spaces, bulkheads, etc.

The paint is a carrier layer (matrix) and is used only to firmly hold the microcapsules on the surface of the protected object, therefore, for this purpose, any types of materials can be used for painting and protecting surfaces, including the whole range of paints and varnishes, nitro varnishes, as well as polymers from the series: epoxy resins , rubbers, silicones, polyurethanes and other synthetic single and multicomponent materials. To bring the mixture of microcapsules with paint to the required working viscosity, any types of solvents can be used, since their short-term exposure at room temperature will not damage or destroy the shells of microcapsules with a homogeneous (monolithic) shell.

Fire-extinguishing paint is applied to a previously prepared and degreased surface using a brush, roller or spray gun with a nozzle diameter of at least 2.5 mm. The consumption of fire-extinguishing paint is calculated based on the internal volume of the protected object, so that the number of microcapsules sprayed with paint is at least 1 g for every 10 liters of volume. Or when applied to the outer surfaces of objects and / or objects based on the mass of microcapsules in an amount of at least 10 g per 1 m ^{2 of the} protected surface. The batch filling method is carried out on an automatic line of PF-112 paint (or other type of paints and varnishes) in a mass of 1 kg in cans with a volume of not more than 1.5 liters and microcapsules in a mass of 0.1 kg in cans with a volume of not more than 0.2 liters.

The main stages of the production of fire extinguishing paint

- The paint is poured into a sealed hopper of an automatic line for filling viscous liquids.

- Open paint cans are installed on the conveyor line.

- Dosed portions of paint are poured into each can using a peristatic pump.

- Filled cans are sealed with a lid, dated and labeled.

- Microcapsules are poured into the hopper of an automatic line for packing bulk products.

- Open jars for microcapsules are installed on the conveyor line.

- Packing of dosed portions of microcapsules into each jar is carried out using a screw feeder.

- The filled jars are sealed with a lid, dated and marked with a label.

Packaged paint and microcapsules are supplied in one transport package (box), complete with a passport and operating manual.

Fire tests

The tests are carried out in a well-ventilated room equipped with a supply and exhaust ventilation system, with walls and a ceiling made of non-combustible and / or refractory material.

The equipment for conducting fire tests includes:

- Metal table - 1 pc.

- Plywood sheets with an area of 1 sq. M are used as a model fire seat for fire tests. (hereinafter MOP-F) - 3 pcs.

- Paint PF-112 (white) - 1 kg.

- Spray gun - 1 pc.

- Gasoline AI-92 - 1 liter.

- Gas burner - 1 pc.

- Stopwatch - 1 pc.

- Laboratory balance - 1 pc.

- Portable thermal imager - 1 pc.

For testing, from a batch of microcapsules by the method of random sampling, three samples weighing 10 g each are taken. The samples are weighed, visually assessed for quality and uniformity of appearance.

Fire test procedure Tests are carried out in the 3rd stage:

1) Check for single extinguishing.

2) Check for double extinguishing.

3) Check for triple extinguishing.

To prepare MOP-F for testing, 300 g of PF-112 paint is mixed with 30 g of microcapsules and, using a spray gun, is applied to one of the sides of all 3 plywood sheets.

Then the MOP-F is laid out on a flat horizontal surface with the painted side up and dried for at least 24 hours. After complete drying, all three samples are weighed and marked.

1. Check for a single extinguishing

1.1 MOP-F No. 1 is placed in the middle of the metal table.

1.2 On MOP-F No. 1 pour 50 gr. gasoline of the IA-92 brand.

1.3 Use a gas burner to initiate a fire.

1.4 The time of extinguishing the fire is recorded using a thermal imager.

Conclusions and Conclusions.

The tests for a sample of microcapsules are considered passed if the fire extinguishing was carried out in a time of no more than 3 seconds, while MOP-F No. 1 lost no more than 3 g in weight.

2. Check for double extinguishing

2.1 MOP-F No. 2 is placed in the middle of the metal table.

2.2 On MOP-F No. 2 pour 80 g of gasoline of the IA-92 brand.

2.3 Use a gas burner to initiate a fire.

2.4 The time of the 1st fire extinguishing is recorded using a thermal imager.

2.5 After 5-10 seconds, the second ignition is initiated using a gas burner.

2.6 The time of the 2nd fire extinguishing is recorded using a thermal imager.

Conclusions and Conclusions.

Tests for a sample of microcapsules are considered passed if the 1st fire extinguishing was carried out in no more than 3 seconds, and the 2nd fire extinguishing was carried out in no more than 5 seconds, while MOP-F No. 2 lost no more than 5 g.

3. Check for triple extinguishing

3.1 MOP-F No. 3 is installed in the middle of the metal table.

3.2 Pour 100 g of IA-92 gasoline into MOP-F No. 3.

3.3 Use a gas burner to initiate a fire.

3.4 The time of the 1st fire extinguishing is recorded using a thermal imager.

3.5 After 5-10 seconds, the 2nd ignition is initiated using the gas burner.

3.6 The time of the 2nd fire extinguishing is recorded using a thermal imager.

3.7 After 5-10 seconds, the 3rd ignition is initiated using the gas burner.

3.8 The time of the 3rd fire extinguishing is recorded using a thermal imager.

Conclusions and Conclusions.

Tests for a sample of microcapsules are considered passed if the 1st fire extinguishing was carried out in a time of no more than 3 seconds, the 2nd fire extinguishing was carried out in a time of no more than 5 seconds, the 3rd fire extinguishing was carried out in a time of no more than 8 seconds, while MOP- Form No. 3 lost no more than 8 g in weight.

Example No. 2 Fire extinguishing plates.

Autonomous fire extinguishing installations in the form of fire extinguishing plates are designed to extinguish fires in volumes such as sockets, switches, switch boxes, switchboards, electrical cabinets, cabinets and control panels, safes, storehouses and other objects with a degree of protection IP20 and higher.

Serial production of fire extinguishing plates is carried out by depositing a suspension of the compound with microcapsules onto a substrate using a depositing machine, followed by applying an adhesive layer and a protective film to the back side of the substrate.

As a base (substrate) for the plate, a PVC sheet (membrane) with a thickness of no more than 0.3-0.5 mm is used. On one side, the substrate is coated with a reflective layer of aluminum powder with a thickness of no more than 50 microns by means of vacuum deposition. Such a coating practically does not have thermal conductivity, but in turn will contribute to trapping additional heat from the IR radiation of the flame for accumulation in the polymer matrix layer, which will lead to the activation of microcapsules at earlier stages of fire development, regardless of the heating rate of the protected volume (heat spread) , as well as movement in the protected volume of convection flows of heated air and combustion products.

As a polymer matrix, it is proposed to use a two-component polyurethane compound with a Shore hardness of 30. By adding no more than 1-3% of distilled water to the compound, the effect of chemical perforation (porosity) of polyurethane is achieved, which will facilitate faster heat penetration into the plate and the absence of interference with release agent.

A self-adhesive paper machine is used to apply the adhesive layer and the protective film to the back of the substrate. Non-combustible acrylic or silicone glue can be used as an adhesive base. Waterproofed paper can be used as a protective film. It is allowed to apply the manufacturer's logo to the protective film, as well as pictograms and images that explain the method of mounting fire extinguishing plates.

The main stages of the production of fire extinguishing plates

- PVC substrate, supplied in rolls, is cut into rectangular sheets with dimensions of 30 × 40 cm, which are placed on the bottom of the cassettes with a side height not exceeding 1.0-1.5 mm.

- Into the bowl of the planetary mixer at a blade speed of 80-100 rpm. 2-component polyurethane is poured in: 2 kg of component A and 2 kg of component B. The mixing process is carried out for at least 5 minutes until a homogeneous polymer is obtained.

- To the obtained polymer at a blade speed of 120-140 rpm. add 20-40 g of red dye. The mixing process is carried out for at least 5 minutes until a homogeneous mixture is obtained.

- To the resulting mixture at a blade rotation speed of 120-140 rpm. add 30-60 g of distilled water. The mixing process is carried out for at least 5 minutes until a homogeneous emulsion is obtained.

- Into the resulting emulsion at a blade rotation speed of 40-60 rpm. small portions (no more than 500 g) send 6 kg of microcapsules. The mixing process is carried out for at least 5 minutes until a homogeneous suspension is obtained.

- The resulting suspension is poured into the hopper of a semi-automatic jigging machine.

- Cassettes with a substrate are loaded into the cassette receiver and, at the operator's command, each cassette is pushed by a broaching mechanism under the slotted nozzle of the hopper, from which an even layer of suspension is deposited to the height of the cassette side. The suspension is cast into one cassette in a time not exceeding 3-5 seconds.

- At the end of the casting process, the cassettes are collected in the cassette collector of the jigging machine.

- From the cassette collector, the cassettes are transferred to a drying rack, where polymerization (vulcanization) of composite plates takes place at room temperature for 24 hours.

- The finished composite plate is removed from the cassettes and passed through a machine for the production of self-adhesive paper, where an adhesive layer with a thickness of not more than 50-100 microns and a layer of protective paper are applied.

- The finished fire extinguishing plates are stacked and cut by a printing guillotine to the required size of products to protect the corresponding volume from 0.5 to 80 liters.

- Sliced products are sorted and sealed in packaging on the packaging line.

Fire tests

The tests are carried out in a well-ventilated room equipped with a supply and exhaust ventilation system, with walls and a ceiling made of non-combustible and / or refractory material.

The equipment for conducting fire tests includes:

- Metal table - 1 pc.

- A metal box with a transparent fire-resistant glass door (L × H × D 25 × 25 × 16 cm) with a volume of 10 liters (hereinafter box No. 1) - 1 pc.

- Metal box with a transparent fire-resistant glass door (L × H × D 32 × 50 × 25 cm) with a volume of 40 liters (hereinafter box No. 2) - 1 pc.

- A metal box with a transparent fire-resistant glass door (L × H × D 50 × 64 × 25 cm) with a volume of 80 liters (hereinafter box No. 3) - 1 pc.

- Model fire center in the form of a metal cup 5 cm in diameter and at least 3 cm high (hereinafter MOP-5) - 1 pc.

- Gasoline AI-92 - 1 liter.

- Gas burner - 1 pc.

- Stopwatch - 1 pc.

- Laboratory balance - 1 pc.

- Portable thermal imager - 1 pc.

For testing, samples of fire extinguishing plates with dimensions of 25 cm ² (5 × 5 cm) are taken from a batch of products by random sampling - 3 pcs. (hereinafter, the plate type No. 1), 100 cm ² (10 × 10 cm) - 3 pcs. (hereinafter the plate type No. 2) and 200 cm ² (10 × 20 cm) - 3 pcs. (hereinafter plate type No. 3). The samples are weighed, visually assessed for quality and uniformity in appearance, and measured in length, width and thickness before and after testing.

Fire test procedure

The tests are carried out in the 3rd stage:

1) Checking plates type No. 1 for fire extinguishing in box No. 1.

2) Inspection of type 2 plates for fire extinguishing in box 2.

3) Checking plates type No. 3 for fire extinguishing in box No. 3.

To ensure the flow of fresh air to the MOP-5, three holes with a diameter of at least 3.5 cm are drilled in the bottom of all types of boxes. To ensure the outflow of combustion products, 1 hole with a diameter of at least 3.5 cm is drilled in the upper right corner of the boxes.

1. Checking plates type No. 1 for fire extinguishing in box No. 1

1.1 Drawer # 1 is placed in the middle of the metal table.

1.2 In the upper part of the box, with the active layer downward, glue a plate type No. 1

1.3 MOP-5 is installed at the bottom of the box.

1.4 50 g of gasoline of the IA-92 brand is poured into MOP-5.

1.5 Use a gas burner to initiate a fire.

1.6 After 5-10 seconds of free burning, the drawer door is closed.

1.7 The time to extinguish the fire is recorded using a thermal imager.

Conclusions and Conclusions.

Tests for plate samples of type No. 1 are considered passed if fire extinguishing was carried out within 15 seconds after opening the box door, repeated ignition of MOP-5 was not recorded, and the weight of the plate decreased by no more than 1.1 g.

2. Checking plates type No. 2 for fire extinguishing in box No. 2

2.1 In the middle of the metal table, place box No. 2.

2.2 In the upper part of the box, with the active layer downward, a plate of type No. 2 is glued.

2.3 MOP-5 is installed at the bottom of the box.

2.4. 100 g of IA-92 gasoline are poured into MOP-5.

2.5 Use a gas burner to initiate a fire.

2.6 After 5-10 sec. free burning, the drawer door is closed.

2.7 The time to extinguish the fire is recorded using a thermal imager.

Conclusions and Conclusions.

The tests for plate samples of type No. 2 are considered passed if the fire extinguishing was carried out within a time not more than 30 seconds after the door of the box was opened, repeated ignition of the MOP-5 was not recorded, and the mass of the plate decreased by at least 4.4 g.

3. Checking plates type No. 3 for fire extinguishing in box No. 3.

3.1 In the middle of the metal table, place box No. 3.

3.2 In the upper part of the box with the active layer downwards, glue a plate of type No. 3.

3.3 MOP-5 is installed at the bottom of the box.

3.4 In MOP-5, 150 g of gasoline of the IA-92 brand is poured.

3.5 Use a gas burner to initiate a fire.

3.6 After 5-10 sec. free burning, the drawer door is closed.

3.7 The time to extinguish the fire is recorded using a thermal imager.

Conclusions and Conclusions.

Tests for plate samples of type No. 3 are considered passed if the fire extinguishing was carried out in a time not exceeding 45 seconds. after opening the door of the box, the repeated ignition of the MOP-5 was not recorded, and the mass of the plate decreased by at least 8.8 g.

Example No. 3 Fire extinguishing capes.

Fire-extinguishing capes of active principle of action are a modification of standard fire-protective capes widely used in various industries. Standard fireproof capes are intended for use as primary fire extinguishing means during welding, as well as at fire hazardous facilities in accordance with fire safety standards approved by law, such as flammable storage facilities, industrial, municipal and other facilities.

Abroad, a huge market for the sale of fireproof capes, in addition to the industrial and public sector, is aimed at the HoReCa segment (hotels, restaurants and cafes) for use in kitchens, the acquisition of trucks and cars, equipment of river and sea vessels. In the EU countries, capes are compulsorily regulated for use in facilities equipped with fireplaces to extinguish the spontaneous combustion of woodpiles with wood or another type of fuel.

A significant drawback of standard fireproof capes is their low efficiency in case of improper use, especially when incomplete and / or loose coverage of the fire source, which does not exclude the intake of fresh air and the outflow (convection) of combustion products, as well as limiting the possibility of extinguishing only unburned fire the earliest stage of the fire.

Basically, a cheap material made of asbestos or fiberglass, which have an average degree of heat resistance (about 500 ° C), is used as a basis for fireproof capes. The presence of non-dense weaving, kinks and holes along the contours of the folds can make the cape completely useless for fire extinguishing or as a means of evacuating people from the heat affected zone of a fire.

Serial production of fire-extinguishing capes is carried out by the method of coordinate layout of the compound mixed with microcapsules on the surface of a heat-resistant fabric selected from the range: asbestos, fiberglass, basalt, silica or arselon. The main stages of production:

- The silica cloth supplied in rolls is cut into square pieces measuring 120 × 120 cm.

- Polyurethane with a Shore hardness of 10 in the amount of 210 g is mixed with microcapsules in the amount of 120 g until a homogeneous suspension.

- The resulting suspension is poured into the print head of a 3D Printer with a print area of 3 × 3 meters.

- 4 pieces of silica cloth are placed on the print field on markers.

- According to the program, the compound is laid out with a solid line 5.0 mm wide with a thickness of 1.0-1.5 mm in the form of a pattern, expanding from the center of the spiral with an increasing step between turns from 20 to 30 mm.

- Layout of the compound on the 1st piece of fabric is carried out in a time not more than 1 minute.

- Drying of pieces of fabric with a printed pattern is carried out in a vertical position in drying chambers for at least 24 hours.

- At the end of the drying cycle, the blankets are stacked.

- With the help of an overlock, the edges of the fire extinguishing cape are processed.

- Finished products are packed in bags, marked and dated.

Fire tests

The tests are carried out in a well-ventilated room equipped with a supply and exhaust ventilation system, with walls and ceilings made of non-combustible and / or refractory material.

The equipment for conducting fire tests includes:

- Metal table - 1 pc.

- A model fire seat in the form of a metal cup with a diameter of 50 cm (standard diameter of a barrel with a capacity of 200 liters) and a height of at least 3 cm (hereinafter MOP-50) - 1 pc.

- Laboratory stand - 2 pcs.

- Gasoline AI-92 - 1 liter.

- Gas burner - 1 pc.

- Stopwatch - 1 pc.

- Laboratory balance - 1 pc.

- Portable thermal imager - 1 pc.

For testing, three samples of fire-extinguishing capes with dimensions of 110 × 110 cm are taken from a batch of products by random sampling.The samples are weighed, visually assessed for quality and uniformity in appearance, and also measured in length and width before and after testing.

Fire test procedure

The tests are carried out in the 3rd stage:

1) Checking a fire-extinguishing cape for extinguishing a fire with full coverage of MOP-50.

2) Checking a fire-extinguishing cape for extinguishing a fire with the 1st open side of the MOP-50.

3) Checking a fire extinguishing cape for extinguishing a fire with 2 open sides of the MOP-50.

During the tests, the time of the primary extinguishing of the fire is recorded, as well as the time for extinguishing the re-ignition.

1. Checking a fire-extinguishing cape for extinguishing a fire with full coverage of MOP-50.

1.5 MOP-50 is placed in the middle of the metal table.

1.6 In the MOP-50, 100 g of gasoline of the IA-92 brand is poured.

1.7 Use a gas burner to initiate a fire.

1.8 After 10-15 seconds of free burning, a fire-extinguishing cape is put on the MOP-50.

1.9 The time to extinguish the fire is recorded using a thermal imager.

1.10 The fire-extinguishing cape is lifted by one edge and, using a gas burner, initiate a re-ignition.

1.11 After 3-5 seconds of free burning, the raised edge of the fire-extinguishing cape is lowered until the MOP-50 is fully covered.

1.12 The time for extinguishing a re-ignition is recorded using a thermal imager

Conclusions and Conclusions.

Tests for a sample of products are considered passed if fire extinguishing with full coverage of MOP-50 was carried out in a time not exceeding 3 seconds, and repeated ignition in a time not exceeding 5 seconds.

2. Checking a fire extinguishing cape for extinguishing a fire with the 1st open side of the MOP-50.

2.1 MOP-50 is installed in the middle of the metal table.

2.2 A laboratory stand is set up nearby, to which one edge of the fire-extinguishing cloak is fixed.

2.3 The free edges of the fire-extinguishing cape are fixed over the MOP-50 with a clothespin.

2.4. 100 g of IA-92 gasoline are poured into MOP-50.

2.5 Use a gas burner to initiate a fire.

2.6 After 10-15 seconds of free burning, the clothespin is unhooked and a fire-extinguishing cape is put on the MOP-50.

2.7 The time to extinguish the fire is recorded using a thermal imager.

2.8 On the side of the raised edge of the fire-extinguishing cape, use a gas burner to reignite.

2.9 The time to extinguish the re-ignition is recorded using a thermal imager.

Conclusions and Conclusions.

Tests for a product sample are considered passed if fire extinguishing with one open side of the MOP-50 was carried out in a time not exceeding 5 seconds, and re-ignition in a time not exceeding 8 seconds.

3. Checking a fire extinguishing cape for extinguishing a fire with 2 open sides of the MOP-50.

3.1 MOP-50 is installed in the middle of the metal table.

3.2 On two opposite sides of the MOP-50 laboratory stands are installed, to which two opposite edges of the fire-extinguishing cape are fixed.

3.3 The free edges of the fire-extinguishing cape are fixed over the MOP-50 with a clothespin.

3.4 100 g of IA-92 gasoline are poured into the MOP-50.

3.5 Use a gas burner to initiate a fire.

3.6 After 10-15 seconds of free burning, the clothespin is uncoupled and a fire-extinguishing cape is put on the MOP-50 from two.

3.7 The time to extinguish the fire is recorded using a thermal imager.

3.8 On the side of any raised edge of the fire-extinguishing cape, using a gas burner, reignite the fire.

3.9 Time to extinguish re-ignition is recorded using a thermal imager

Conclusions and Conclusions.

Tests for a sample of products are considered passed if fire extinguishing with 2 open sides of the MOP-50 was carried out in a time period of no more than 8 seconds, and repeated ignition in a time of no more than 10 seconds.

Industrial applicability

The microencapsulated extinguishing agent according to the present invention is easily miscible with resins, liquid curable rubbers and other matrices and can be used as a filler in extinguishing composite materials, for example, in the form of pastes, plates, films, coatings, foams, technical fabrics, shaped and other products. ...

Specialists in the field of fire extinguishing should understand that by using the method for producing microcapsules according to the invention, it is possible to obtain microencapsulated extinguishing agents capable of ejecting the target liquid product into the external environment at a certain temperature.

Such extinguishing agents can be used in various fields of industry and in various fire extinguishing systems for effective automatic inertialess prevention of fires, both in the form of microcapsule powder and in the composition of fire-extinguishing composite materials - coatings, films, cambric, fire-extinguishing protective fabrics and others.

Claims (12)

1. A method of obtaining a microencapsulated thermoactivated extinguishing agent containing microcapsules having a core of a fire extinguishing agent and a spherical polymer shell with the ability to explosively destruct in the temperature range 90-150 ° C, in which the microcapsules are formed by injection-drop injection under pressure of a heated extinguishing agent into the medium cooled film former placed under reduced pressure, for which the components are mixed in the reactor to prepare the concentrate of the film former, the resulting mixture is cooled at reduced pressure in the reactor, then stirred and recooled to the temperature required to form a stabilized colloidal state of the film former concentrate, while in the tank the installations place a fire extinguishing agent, create the pressure required to remove air bubbles, and with constant stirring, the agent is heated to a certain temperature, depending on the specified temperature of the asset preparation of finished microcapsules, then the heated agent under pressure is fed into the nozzle block and the drops are injected into the reactor into the medium of the cooled concentrate of the film former for a certain time at the speed of rotation of the motor shaft, depending on the specified outer diameter of the finished microcapsules, each heated drop falling into the medium of the concentrate of the film-former, which is in the reactor at a reduced pressure, expands and forms the primary sphere of the microcapsule nucleus, which becomes the center of the activation of the film-former curing process, the cooling nucleus of the microcapsule nucleus in the low-temperature reactor environment is actively compressed, uniformly compressed and creates, after curing, a strong microcapsule shell at the end of the injection cycle, the formed microcapsules are poured, filtered and dried at room temperature. 2. The method according to claim 1, characterized in that in the reactor the concentrate of the film former is cooled to a temperature of +10 - + 15 ° C at a pressure of 0.1-0.5 Atm, then stirred and re-cooled to a temperature of +8 - + 18 ° FROM. 3. The method according to claim 1, characterized in that the agent placed in the tank of the injection unit is heated to a temperature of +35 - + 95 ° C, then under a pressure of 2.0-4.0 Atm is fed into the medium of the cooled film-former concentrate for no more than 20-30 minutes at an engine shaft speed of 1500-2500 rpm. 4. A method according to claim 1, characterized in that a concentrate of a film former is used in the form of a mixture of epoxy resin, diethylene glycol and maleic anhydride. 5. The method according to claim 1, characterized in that a concentrate of a film former is used in the form of a mixture of water, gelatin and sodium sulfate. 6. The method according to claim 1, characterized in that a concentrate of a film former is used in the form of a mixture of water, polyvinyl alcohol and methanol. 7. A method according to claim 1, characterized in that dibromomethane is used as the extinguishing liquid. 8. The method according to claim 1, characterized in that perfluoroketone is used as the extinguishing liquid. 9. The method according to claim 1, characterized in that freon 114B2 is used as the extinguishing liquid. 10. A method according to claim 1, characterized in that microcapsules having an outer diameter in the range of 50-1100 μm are obtained. 11. The method according to claim 1, characterized in that at least 90% of microcapsules having homogeneous physical and chemical properties are obtained in one batch. 12. The method according to claim 1, characterized in that microcapsules are obtained in which the mass of the shell is 4-10% of the mass of the microcapsule.