CN118304607A - Microcapsule fire extinguishing agent and preparation method and application thereof - Google Patents

Abstract

The application relates to the technical field of fire extinguishing materials, in particular to a microcapsule fire extinguishing agent and a preparation method and application thereof. A microcapsule fire extinguishing agent comprises a core material and an outer shell layer; the core material is coated in the outer shell layer; the core material is a low boiling point liquid extinguishing agent, and the outer shell layer comprises a first shell and a second shell from inside to outside; the first shell comprises a plurality of active hydrogen polymer materials, a cross-linking agent and a defoaming agent, and the second shell is polysulfone resin; the adhesion performance of the second shell on the first shell and the synergistic performance of the second shell and the first shell are improved through the active hydrogen of the high polymer material in the first shell; further, a cross-linking agent is adopted in the second shell, so that the compactness and the water resistance of the first shell are improved; the prepared microcapsule fire extinguishing agent has excellent coating rate, water resistance and fire extinguishing performance through the compatibility of the polymer materials of a plurality of active hydrogen in the first shell, the cross-linking agent and the polysulfone resin of the second shell, so that the stability in storage and use is improved.

Description

Microcapsule fire extinguishing agent and preparation method and application thereof

Technical Field

The application relates to the technical field of fire extinguishing materials, in particular to a microcapsule fire extinguishing agent and a preparation method and application thereof.

Background

With the development of technology, the electricity consumption and the electricity consumption products are continuously increased, and the electric fire disaster is more and more severe, so that a great amount of financial loss is caused, and the health and the life of people are taken away. Therefore, the prevention of fire and the use of fire-proof and extinguishing products have been widely appreciated.

The fire-extinguishing products can be divided into active fire-extinguishing products and passive fire-extinguishing products, wherein the active fire-extinguishing products are fire-extinguishing products driven by energy or electricity and can actively detect fire and extinguish fire, and common active fire-extinguishing products comprise a fire automatic alarm system, a spraying system and a foam fire-extinguishing system; the passive fire extinguishing products refer to fire extinguishing products which do not depend on power or energy sources to be directly consumed, and common passive fire extinguishing products comprise fire-proof walls, fireproof doors, fireproof glass and other products for passively controlling fire spread.

The low boiling point liquid fire extinguishing agent has the advantages of low toxicity, high fire extinguishing speed, easy volatilization, no trace residue left after fire extinguishment, no environmental pollution, no damage to disaster-stricken articles and the like, and is widely applied to various important places. However, low boiling point liquid extinguishing agents are less stable and inconvenient to store and carry.

The microcapsule fire extinguishing agent is used as an emerging fire extinguishing medium, and the microcapsule fire extinguishing agent prepared from the low-boiling-point liquid fire extinguishing agent can overcome the problems of instability, inconvenient storage and carrying of the existing low-boiling-point liquid fire extinguishing agent, and is gradually widely applied in the fire-fighting field in recent years.

However, the existing microcapsule fire extinguishing agent generally adopts natural polymer materials such as sodium carboxymethyl cellulose and chitosan or adopts polymer materials such as epoxy resin, polyurethane or acrylic resin as wall materials, and the coating effect and the water resistance of the prepared microcapsule fire extinguishing agent are poor, so that the wall materials of the microcapsule fire extinguishing agent are not ideal for protecting core materials.

Disclosure of Invention

The application provides a microcapsule fire extinguishing agent, a preparation method and application thereof, and aims to solve the problems of poor coating effect and poor water resistance of the existing microcapsule fire extinguishing agent.

In a first aspect, the present application provides a microcapsule fire extinguishing agent:

A microcapsule fire extinguishing agent comprises the following components in percentage by mass (0.27-12): 1 and a core material and a shell layer; the core material is coated in the outer shell layer;

The core material is a low-boiling point liquid extinguishing agent, and the shell layer comprises a first layer of shell and a second layer of shell from inside to outside; the raw materials of the first shell comprise a high polymer material containing a plurality of active hydrogens, a cross-linking agent and a defoaming agent, the high polymer material and the cross-linking agent react to form a network structure, and the second shell is polysulfone resin.

The polysulfone membrane has better rigidity and toughness and excellent high-temperature resistance, heat-oxidation resistance and creep resistance, however, the polysulfone structure contains more benzene rings, the chains are stiffer, the adhesion force of the membrane layer is poorer, the adhesion effect between the polysulfone membrane and other membrane layers is possibly poor, and the comprehensive performance of the microcapsule fire extinguishing agent of the polysulfone resin is further influenced.

By adopting the technical scheme, the microcapsule fire extinguishing agent adopts polysulfone resin as the second layer of shell, so that the heat resistance of the microcapsule fire extinguishing agent is improved, and the storage stability of the microcapsule fire extinguishing agent is further improved.

Further, a first shell is adopted between the core material and the second shell, the first shell comprises a polymer material containing a plurality of active hydrogens, a cross-linking agent and a defoaming agent, the core material is coated by the polymer material containing the active hydrogens to form latex particles with smaller particle size, and therefore the coating rate of the outer shell layer on the core material and the stability of the core material are improved; and the active hydrogen of the high polymer material in the first shell promotes the adhesion performance of the second shell on the first shell, the high polymer material containing a plurality of active hydrogen is compatible with polysulfone resin with good toughness, the problem of poor adhesion performance of the polysulfone membrane of the second shell is improved, the synergistic effect between the first shell and the second shell is promoted, and the prepared microcapsule fire extinguishing agent has higher stability, coating rate, fire extinguishing effect and water resistance, and further the stability of the microcapsule fire extinguishing agent in storage and use is promoted.

However, the first shell of the polymeric material of multiple active hydrogens may result in a decrease in the water resistance of the microencapsulated fire suppressant; further, the cross-linking agent is adopted in the second-layer shell, and on the premise of ensuring that the second-layer shell and the first shell have good adhesion performance, the compactness and the water resistance of the first shell are improved by the cross-linking agent.

The microcapsule fire extinguishing agent prepared by the polymer materials of a plurality of active hydrogens in the first shell, the cross-linking agent and polysulfone resin with good toughness and high temperature resistance are compatible for use, so that the microcapsule fire extinguishing agent has excellent stability, coating rate, fire extinguishing performance and water resistance, and the stability of the microcapsule fire extinguishing agent in storage and use is further improved.

Preferably, the mass ratio of the first layer shell to the second layer shell is (1.87-15): 1, a step of; the mass ratio of the polymer material to the cross-linking agent is (0.33-4.17): 1, a step of; the high polymer material is one or more of gelatin, sodium alginate, chitosan, acacia, polyglutamic acid, beta-cyclodextrin, sodium carboxymethyl cellulose, hydroxypropyl methyl cellulose and octenyl succinic acid esterified starch; the molecular weight of the polysulfone is 10000-50000.

By adopting the technical scheme, the mass ratio of the first shell to the second shell, the mass ratio of the high polymer material to the cross-linking agent, the type of the high polymer material and the molecular weight of polysulfone are optimized, and the coating rate, the stability and the water resistance of the microcapsule fire extinguishing agent are further improved.

Preferably, the polymer material is a composition of gelatin and sodium alginate; the cross-linking agent is glutaraldehyde and/or calcium chloride.

Preferably, the cross-linking agent adopts glutaraldehyde and calcium chloride; the mass ratio of the sodium alginate to the gelatin to the calcium chloride to the glutaraldehyde is (0.1-5): (0.24-2.4): (0.5-10): (0.1-2).

By adopting the technical scheme, the types and the weights of the polymer materials and the cross-linking agent are optimized, and the coating rate and the water resistance of the microcapsule fire extinguishing agent are further improved.

The high polymer material adopts compatibility of gelatin and sodium alginate, and the carboxyl in the sodium alginate and the amino in the gelatin have stronger acting force, so that the density and the strength of the first shell layer are enhanced.

Further, the crosslinking agent glutaraldehyde and/or calcium chloride is adopted, the calcium chloride reacts with sodium alginate, glutaraldehyde reacts with active hydrogen in gelatin and sodium alginate, the density and strength of the first shell layer are further improved, and the coating rate and water resistance of the microcapsule fire extinguishing agent are further improved.

Preferably, the core material is at least one of tetrafluorodibromoethane, dibromomethane, decafluoro-3-methoxy-4- (trifluoromethyl) pentane, trifluoro dichloroethane, bromotrifluoropropene and perfluoro hexanone.

Preferably, the microcapsule fire extinguishing agent has a particle size of 100-500 μm.

Through adopting above-mentioned technical scheme, the kind of preferred core, core and shell compatibility for the microcapsule fire extinguishing agent of preparing has better cladding rate, water resistance, stability and fire extinguishing effect.

In a second aspect, the application provides a method for preparing a microcapsule fire extinguishing agent:

A preparation method of a microcapsule fire extinguishing agent comprises the following preparation steps:

Preparation of an aqueous solution of a high polymer material: preparing the high polymer materials into solutions with mass fractions of 0.1-5%;

Preparation of the fire extinguishing agent emulsion: mixing and emulsifying the high polymer material aqueous solution, the defoaming agent and the core material to obtain a fire extinguishing agent emulsion;

Preparation of fire extinguishing agent emulsion particles: adding the fire extinguishing agent emulsion into a solution of 0.1-10% of cross-linking agent by mass percent to stir,

Standing, filtering, cleaning and drying to obtain fire extinguishing agent emulsion particles;

Preparation of microcapsule fire extinguishing agent: adding the fire extinguishing agent emulsion particles into water, adding polysulfone solution during stirring, and then stirring, filtering, cleaning and drying to obtain the microcapsule fire extinguishing agent.

By adopting the technical scheme, the microcapsule fire extinguishing agent with good coating rate, water resistance and stability is prepared.

Preferably, the high polymer material aqueous solution consists of 0.1-5% sodium alginate aqueous solution by mass and 0.8% gelatin aqueous solution by mass; the mass ratio of the sodium alginate aqueous solution to the gelatin aqueous solution to the defoamer to the core material is 1: (0.3-3): (0.001-0.05): (0.05-0.3);

Dripping the fire extinguishing agent emulsion into 0.5-10% calcium chloride aqueous solution by mass percent for gelation reaction, and then standing, filtering and cleaning to prepare a rudiment of fire extinguishing agent emulsion particles; then placing the rudiment of the fire extinguishing agent latex particles in an aqueous solution of dialdehyde with the mass fraction of 0.1% -2%, standing for 12-48h, filtering, cleaning and drying to obtain the fire extinguishing agent latex particles; the polysulfone solution is a dichloromethane solution of polysulfone with the mass fraction of 2% -10%; the mass ratio of the fire extinguishing agent latex particles to the water is 1: (7.28-30).

By adopting the technical scheme, the mass ratio of the sodium alginate aqueous solution to the gelatin aqueous solution to the defoaming agent to the core material is optimized by optimizing the concentration of the sodium alginate aqueous solution and the gelatin aqueous solution, so that the prepared microcapsule fire extinguishing agent has good coating rate, water resistance and fire extinguishing effect.

Optimizing the sequence of treating the extinguishing agent emulsion by the cross-linking agent, and further improving the density and strength of the second-layer shell; thereby improving the coating rate, water resistance and fire extinguishing effect of the prepared microcapsule fire extinguishing agent.

Preferably, in the preparation of the fire extinguishing agent emulsion, the stirring speed is 1000-3000r/min, the stirring time is 5-30min, and the temperature is 10-40 ℃;

In the preparation of the fire extinguishing agent latex particles, the rudiment of the fire extinguishing agent latex particles is placed in a dialdehyde water solution and then is kept stand for 12-48h at the temperature of-5-10 ℃.

By adopting the technical scheme, the reaction conditions of the fire extinguishing agent emulsion, the aqueous solution of calcium chloride and the aqueous solution of glutaraldehyde are optimized, and the coating rate, the water resistance and the fire extinguishing effect of the prepared microcapsule fire extinguishing agent are further improved.

At a lower temperature, the reaction speed of glutaraldehyde and the emulsion particle rudiment of the fire extinguishing agent is lower, so that the crosslinking density of the second layer of shell is better improved, and the water resistance of the prepared microcapsule fire extinguishing agent is further improved.

After the fire extinguishing agent emulsion reacts with the aqueous solution of calcium chloride, a network structure with certain crosslinking density is formed, and glutaraldehyde reacts on the surface layer of the network structure in a large amount under the condition of higher temperature, so that the crosslinking density of the surface layer is increased rapidly, the glutaraldehyde amount entering the first shell is reduced, the crosslinking density in the first shell is reduced, and the water resistance of the prepared microcapsule fire extinguishing agent is reduced; under the conditions of lower temperature and longer standing time, glutaraldehyde can be well immersed into the first shell to react, so that the water resistance of the first shell and the microcapsule fire extinguishing agent is improved.

In a third aspect, the present application provides an application of a microcapsule fire extinguishing agent:

The microcapsule fire extinguishing agent can be applied to passive fire extinguishing products and fireproof fire extinguishing products, and can be specifically added into resin or rubber as fire extinguishing agent filler; the fire-proof fire-extinguishing agent can be prepared into passive fire-extinguishing products such as fire-proof patches, sheets, coatings, strips, room-temperature curing slurry, plates and the like; can be applied to fire-proof and fire-extinguishing products such as boxes, cables and the like.

The microcapsule fire extinguishing agent prepared by the application has better water resistance, stability and fire extinguishing performance, is convenient to store and transport, and widens the application scenes of the prepared passive fire extinguishing product and fireproof fire extinguishing product.

In summary, the application has the following beneficial effects:

1. A microcapsule fire extinguishing agent comprises a core material and an outer shell layer; the core material is coated in the outer shell layer; the core material is a low boiling point liquid extinguishing agent, and the outer shell layer comprises a first shell and a second shell from inside to outside; the first shell comprises a plurality of active hydrogen polymer materials, a cross-linking agent and a defoaming agent, and the second shell is polysulfone resin; the adhesion performance of the second shell on the first shell and the synergistic performance of the second shell and the first shell are improved through the active hydrogen of the high polymer material in the first shell; further, a cross-linking agent is adopted in the second shell, so that the compactness and the water resistance of the first shell are improved; the prepared microcapsule fire extinguishing agent has excellent coating rate, water resistance and fire extinguishing performance through the compatibility of the polymer materials of a plurality of active hydrogen in the first shell, the cross-linking agent and the polysulfone resin of the second shell, so that the stability in storage and use is improved.

1. Preferably, the high polymer material is sodium alginate and gelatin, and the cross-linking agent is glutaraldehyde and calcium chloride; the mass ratio of the sodium alginate to the gelatin to the calcium chloride to the glutaraldehyde is (0.1-5): 0.24: (0.5-10): (0.1-2); the types and the weights of the polymer material and the cross-linking agent are optimized, and the coating rate and the water resistance of the microcapsule fire extinguishing agent are further improved.

3. Preferably, in the preparation of the fire extinguishing agent emulsion particles, the stirring condition in the gelation reaction is 1000-3000r/min, the time is 5-30min, and the temperature is 10-40 ℃; placing the extinguishing agent emulsion particle embryonic form into glutaraldehyde water solution at-5-10deg.C, standing for 12-48 hr; the coating rate, the water resistance and the fire extinguishing effect of the prepared microcapsule fire extinguishing agent are further improved by optimizing the reaction conditions of the fire extinguishing agent emulsion, the aqueous solution of calcium chloride and the aqueous solution of glutaraldehyde in sequence.

Drawings

Fig. 1: schematic structural diagram of the microcapsule fire extinguishing agent of example 1.

Fig. 2: thermal weight loss graphs of the microcapsule fire extinguishing agents of example 1, example 2, comparative example 1 and comparative example 2.

Reference numerals illustrate:

1. a fire extinguishing agent; 2. a first shell (sodium alginate/gelatin shell); 3. a second housing (polysulfone housing); 4. thermal weight loss curve of the microcapsule fire extinguishing agent of example 1; 5. thermal weight loss curve of the microcapsule fire extinguishing agent of example 2; 6. a thermal weight loss curve of the microcapsule fire extinguishing agent of comparative example 1; 7. thermal weight loss curve of the microcapsule fire extinguishing agent of comparative example 2.

Detailed Description

Examples

Example 1, a microcapsule fire extinguishing agent, using the raw materials shown in table 1, comprises a core material and an outer shell layer; the core material is coated in the shell layer; the shell layer comprises a first shell and a second shell from inside to outside, the structural schematic diagram of the microcapsule fire extinguishing agent is shown in figure 1, and the preparation method comprises the following steps:

Preparation of an aqueous solution of a high polymer material: preparing 1.5% sodium alginate aqueous solution (sodium alginate: food grade, executive standard: national standard, active ingredient content 99%, white powder granule) and 0.8% gelatin aqueous solution (gelatin molecular weight 50000, food grade).

Preparation of fire extinguishing agent emulsion particles:

Mixing and stirring the sodium alginate aqueous solution, the gelatin aqueous solution, the defoaming agent and the core material (adopting perfluoro-hexanone) at the stirring speed of 2000r/min for 20min and the temperature of 25 ℃ to obtain a fire extinguishing agent emulsion;

Slowly dripping the fire extinguishing agent emulsion into 1% calcium chloride aqueous solution by mass fraction for gelation reaction (the reaction temperature is 20+/-10 ℃), filtering the precipitated particles, washing with deionized water for 3 times, putting into glutaraldehyde aqueous solution by mass fraction of 1%, standing at 0 ℃ for 24 hours, filtering, washing and drying to obtain the fire extinguishing agent emulsion particles.

Preparation of microcapsule fire extinguishing agent: dissolving polysulfone (with molecular weight of 20000) in methylene dichloride to obtain polysulfone solution with mass fraction of 8%, adding the prepared fire extinguishing agent latex particles into 100g deionized water (mass ratio of fire extinguishing agent latex particles to water of 1:7.28) to start stirring, slowly adding polysulfone solution at stirring speed of 200r/min, keeping stirring state until solvent is completely volatilized, filtering, cleaning, and drying to obtain microcapsule fire extinguishing agent.

Example 2, a microcapsule fire extinguishing agent, differs from example 1 in that tetrafluorodibromoethane was used as the core material, and polysulfone had a molecular weight of 25000.

Examples 3 to 5, a microcapsule fire extinguishing agent, which is different from example 1 in the kind of raw materials, the weight of raw materials and the preparation process parameter settings, are shown in table 1.

Table 1: list of raw material types, raw material weights, and preparation process parameters used in the microcapsule fire extinguishing agents of examples 1 to 5

Wherein sodium alginate, gelatin, calcium chloride, dialdehyde, polysulfone and defoamer are used as raw materials of the outer shell layer.

Wherein the weight of the fire extinguishing agent latex particles is the sum of the weight of the core material, the polymer material and the cross-linking agent raw material.

Example 6, a microcapsule fire extinguishing agent, differs from example 1 in that sodium alginate was used in place of gelatin in equal amounts.

Example 7, a microcapsule fire extinguishing agent, differs from example 1 in that hydroxypropyl methylcellulose (7 wt% hydroxypropoxyl content, 27wt% methoxy content) was used in place of gelatin in equal amounts.

Example 8, a microencapsulated fire extinguishing agent, differs from example 1 in that an equivalent amount of glutaraldehyde of calcium chloride is used.

Example 9, a microencapsulated fire extinguishing agent, differs from example 1 in that glutaraldehyde is used in an equivalent amount of calcium chloride.

Example 10, a microcapsule fire extinguishing agent, was different from example 1 in that in the preparation of the fire extinguishing agent latex particles, the rudiment of the fire extinguishing agent latex particles was placed in an aqueous solution of dialdehyde and then allowed to stand at 15℃for 15 hours.

Example 11, a microcapsule fire extinguishing agent, was different from example 1 in that in the preparation of the fire extinguishing agent latex particles, the rudiment of the fire extinguishing agent latex particles was placed in an aqueous solution of dialdehyde and then allowed to stand at-8℃for 55 hours.

Comparative example

Comparative example 1, a microcapsule fire extinguishing agent, differs from example 1 in that a polysulfone solution was not used;

the raw materials are adopted: 10g of perfluoro hexanone; 100g of sodium alginate aqueous solution; 30g of gelatin aqueous solution; 100g of calcium chloride aqueous solution; 100g of glutaraldehyde aqueous solution; 0.3g of defoamer.

The preparation method comprises the following steps:

mixing and stirring 1.5wt% of sodium alginate aqueous solution, 0.8wt% of gelatin aqueous solution, a defoaming agent and perfluoro-hexanone, wherein the stirring speed is 2000r/min, the stirring time is 20min, and the temperature is 25 ℃ to obtain perfluoro-hexanone-sodium alginate/gelatin emulsion;

slowly dripping the perfluor hexanone-sodium alginate/gelatin emulsion into 1wt% calcium chloride aqueous solution for gelation reaction, filtering the precipitated particles, washing with deionized water for 3 times, putting into aqueous solution containing 1wt% glutaraldehyde, standing for 24h at 0 ℃, filtering, washing, and drying to obtain the microcapsule fire extinguishing agent.

Comparative example 2, a microcapsule fire extinguishing agent, differs from example 1 in that a polysulfone solution was not used; an aqueous gelatin solution and an aqueous glutaraldehyde solution are not used;

The raw materials are adopted: 10g of perfluoro hexanone; 100g of sodium alginate aqueous solution; 100g of calcium chloride aqueous solution; 0.3g of defoamer.

The preparation method comprises the following steps:

Mixing and stirring 1.5wt% of sodium alginate aqueous solution, a defoaming agent and perfluoro-hexanone, wherein the stirring speed is 2000r/min, the stirring time is 20min, and the temperature is 25 ℃ to obtain perfluoro-hexanone-sodium alginate emulsion; slowly dripping the perfluor hexanone-sodium alginate emulsion into 1.0wt% calcium chloride aqueous solution for gelation reaction, filtering, cleaning and drying the precipitated particles to obtain the microcapsule fire extinguishing agent.

Comparative example 3, a microcapsule fire extinguishing agent, differs from example 1 in that no crosslinking agent was used.

Comparative example 4, a microcapsule fire extinguishing agent, was different from example 1 in that resorcinol-formaldehyde resin was substituted for polysulfone resin in equal amount.

Comparative example 5, a microcapsule fire extinguishing agent, differs from example 1 in that a polysulfone solution was not used; glutaraldehyde aqueous solution and defoamer are not used;

The raw materials are adopted: 10g of perfluoro hexanone; 100g of sodium alginate aqueous solution; 30g of gelatin aqueous solution; 100g of calcium chloride aqueous solution.

The preparation method comprises the following steps:

mixing and stirring 1.5wt% of sodium alginate aqueous solution, 0.8wt% of gelatin aqueous solution and perfluoro-hexanone at the stirring speed of 2000r/min for 20min and the temperature of 25 ℃ to obtain perfluoro-hexanone-sodium alginate/gelatin emulsion;

Slowly dripping the perfluor hexanone-sodium alginate/gelatin emulsion into 1.0wt% calcium chloride aqueous solution for gelation reaction, filtering, cleaning and drying the precipitated particles to obtain the microcapsule fire extinguishing agent.

This comparative example produced a large amount of foam during emulsification, and failed to emulsify.

Performance test

Test 1: embedding rate and release temperature

And confirming the embedding rate and the release temperature of the test sample according to a thermogravimetric analysis method by adopting a thermogravimetric analyzer with reference to GBT 27761-2011.

Test 2: extinguishing time of fire

60G of microcapsule powder is added into 80g of water-soluble melamine-formaldehyde resin, stirred for 10 minutes, poured into a mould and dried and molded at 40 ℃ to obtain the perfluoro-hexanone fire extinguishing tablet. A layer of polyurea with the thickness of about 50 mu m is coated on the surface of the fire extinguishing sheet, and a layer of double-sided film is coated on the back of the fire extinguishing sheet to prepare the fire extinguishing patch with the thickness of 2mm and containing the microcapsule fire extinguishing agent.

The fire extinguishing paste is stuck to the top of a 0.1L box body, a burning disc filled with kerosene is placed at the bottom of the box body, the kerosene in the burning disc is ignited, the box door is closed, and the time for extinguishing the flame is calculated.

Test 3: water resistance

15+ -5 G of the test sample was taken and placed in 500mL of water, the morphological change of the test sample (microcapsule fire extinguishing agent) was observed once per day at the agreed time, and whether swelling occurred or not was recorded, and continuous observation was performed for 20 days.

Test sample: taking microcapsule fire extinguishing agents of examples 1 to 11 as example samples; the microcapsule fire extinguishing agents of comparative examples 1 to 4 were used as comparative examples.

Test results: the experimental results of the embedding rate and release temperature of the microcapsule fire extinguishing agents of examples 1 to 11 and comparative examples 1 to 4, and the fire extinguishing time of the fire extinguishing patches prepared using the microcapsule fire extinguishing agents of examples 1 to 11 and comparative examples 1 to 4 are shown in table 2.

Table 2: examples 1 to 11 and comparative examples 1 to 4, and test result lists of the fire extinguishing time of the fire extinguishing patches prepared using the microcapsule fire extinguishing agents of examples 1 to 11 and comparative examples 1 to 4

It can be seen in combination with examples 1 to 11 and comparative examples 1 to 4 and with table 2 that:

Compared with comparative examples 1 to 3, the microcapsule fire extinguishing agent of example 1 has higher embedding rate and release temperature, shorter fire extinguishing time and better water resistance, which indicates that the microcapsule fire extinguishing agent adopts the compatibility of a first shell and a second shell (polysulfone resin) containing a plurality of active hydrogen, a cross-linking agent and a defoaming agent, so that the prepared microcapsule fire extinguishing agent has excellent embedding rate, water resistance and fire extinguishing effect and higher release temperature; possibly because of the active hydrogen of the high polymer material in the first shell, the adhesion performance of the second shell on the first shell and the cooperative performance between the two are improved; the cross-linking agent is adopted in the second shell, and on the premise of ensuring that the second shell has better adhesion performance on the first shell, the compactness and the water resistance of the first shell are improved by the cross-linking agent; the prepared microcapsule fire extinguishing agent has higher release temperature, better water resistance, coating rate and fire extinguishing effect by the compatibility of the high polymer material containing a plurality of active hydrogen in the first shell, the cross-linking agent and the polysulfone resin of the second shell.

Compared with comparative example 4, the microcapsule fire extinguishing agent of example 1 has higher embedding rate and release temperature, shorter fire extinguishing time and better water resistance, which indicates that the second shell has better compatibility with the first shell due to better stability compared with resorcinol-formaldehyde resin, so that the microcapsule fire extinguishing agent has better stability, and further has better toughness than polysulfone resin, thereby being beneficial to the adhesion of polysulfone on the first shell of the high polymer material containing a plurality of active hydrogen, and having better synergistic effect.

The lower entrapment and release temperatures and longer fire-extinguishing times of the microcapsule fire-extinguishing agent of example 5 compared to example 3 may be due to the lower mass ratio of the first layer shell to the second layer shell in the preparation of the microcapsule fire-extinguishing agent of example 5 using less aqueous sodium alginate than example 3; the weight of the first shell is small, the emulsifying effect of the core material is poor, the embedding rate is reduced, and the fire extinguishing time is prolonged; in addition, under the condition that the cross-linking agent is certain, the content of sodium alginate is reduced, active hydrogen in the first shell is reduced, acting force between the first shell and the second shell is weakened, and water possibly easily permeates and stays between the first shell and the second shell, so that the water resistance of the microcapsule fire extinguishing agent is reduced.

Compared with examples 5 to 9, the microcapsule fire extinguishing agent of example 1 has higher embedding rate and release temperature, shorter fire extinguishing time and better water resistance, which indicates that sodium alginate, gelatin, calcium chloride and glutaraldehyde are adopted in the first shell for compatibility, thus improving the embedding rate, release temperature and water resistance of the microcapsule fire extinguishing agent and reducing the fire extinguishing time; the fire extinguishing patch adopting the microcapsule fire extinguishing agent has shorter fire extinguishing time possibly due to higher embedding rate; the core material has better emulsification effect probably because of the compatibility of sodium alginate and gelatin; the strong acting force is arranged between the sodium alginate and the gelatin, and the calcium chloride reacts with the sodium alginate and the glutaraldehyde reacts with the sodium alginate and the gelatin, so that the strength, the density and the coating rate of the fire extinguishing agent emulsion particles are enhanced, hydrophilic groups on the surfaces of the fire extinguishing agent emulsion particles are reduced, and the water resistance of the microcapsule fire extinguishing agent is further improved.

Compared with examples 10 to 11, the microcapsule fire extinguishing agent of example 1 has higher embedding rate and release temperature and better water resistance, which indicates that in the preparation of the fire extinguishing agent emulsion particles, the rudiment of the fire extinguishing agent emulsion particles is placed in the aqueous solution of dialdehyde, and the rudiment of the fire extinguishing agent emulsion particles has better water resistance after standing for 12 to 48 hours at the temperature of-5 to 10 ℃; after the fire extinguishing agent emulsion reacts with the aqueous solution of calcium chloride, a network structure with certain crosslinking density is formed, and under the condition of higher temperature, glutaraldehyde is combined on the surface layer of the network structure in a large amount to improve the crosslinking density, so that the glutaraldehyde amount entering the first shell is reduced, the crosslinking density is reduced, and the water resistance of the prepared microcapsule fire extinguishing agent is reduced; under the conditions of lower temperature and longer standing time, glutaraldehyde can be well immersed into the first shell to react, so that the water resistance, strength and coating rate of the first shell and the microcapsule fire extinguishing agent are improved.

When the temperature is too low during standing, the rudiment of the fire extinguishing agent latex particles with certain crosslinking density contracts, gaps among high polymer materials are reduced, glutaraldehyde is difficult to enter, the crosslinking density in the first shell layer is reduced, and the water resistance of the prepared microcapsule fire extinguishing agent is reduced.

The present embodiment is only for explanation of the present application and is not to be construed as limiting the present application, and modifications to the present embodiment, which may not creatively contribute to the present application as required by those skilled in the art after reading the present specification, are all protected by patent laws within the scope of claims of the present application.

Claims (10)

1. The microcapsule fire extinguishing agent is characterized by comprising the following components in percentage by mass (0.27-12): 1 and a core material and a shell layer; the core material is coated in the outer shell layer;

The core material is a low-boiling point liquid extinguishing agent, and the shell layer comprises a first layer of shell and a second layer of shell from inside to outside; the raw materials of the first shell comprise a high polymer material containing a plurality of active hydrogens, a cross-linking agent and a defoaming agent, the high polymer material and the cross-linking agent react to form a network structure, and the second shell is polysulfone resin.

2. The microcapsule fire extinguishing agent according to claim 1, wherein the mass ratio of the first layer shell to the second layer shell is (1.87-15): 1, a step of; the mass ratio of the polymer material to the cross-linking agent is (0.33-4.17): 1, a step of; the high polymer material is one or more of gelatin, sodium alginate, chitosan, acacia, polyglutamic acid, beta-cyclodextrin, sodium carboxymethyl cellulose, hydroxypropyl methyl cellulose and octenyl succinic acid esterified starch; the molecular weight of the polysulfone is 10000-50000.

3. The microcapsule fire extinguishing agent according to claim 2, wherein the polymer material is a combination of gelatin and sodium alginate; the cross-linking agent is dialdehyde and/or calcium chloride.

4. A microcapsule fire extinguishing agent according to claim 3, wherein the cross-linking agent is glutaraldehyde and calcium chloride; the mass ratio of the sodium alginate to the gelatin to the calcium chloride to the glutaraldehyde is (0.1-5): (0.24-2.4): (0.5-10): (0.1-2).

5. The microcapsule fire extinguishing agent according to claim 1, wherein the core material is at least one of tetrafluorodibromoethane, dibromomethane, decafluoro-3-methoxy-4- (trifluoromethyl) pentane, trifluorodichloroethane, bromotrifluoropropene, and perfluoro hexanone.

6. A microcapsule fire extinguishing agent according to claim 1, wherein the microcapsule fire extinguishing agent has a particle size of 100-500 μm.

7. A method of preparing a microcapsule fire extinguishing agent according to any of claims 1-6, comprising the steps of:

Preparation of an aqueous solution of a high polymer material: preparing the high polymer materials into solutions with mass fractions of 0.1-5%;

Preparation of the fire extinguishing agent emulsion: mixing and emulsifying the high polymer material aqueous solution, the defoaming agent and the core material to obtain a fire extinguishing agent emulsion;

Preparation of fire extinguishing agent emulsion particles: adding the fire extinguishing agent emulsion into a solution of 0.1-10% of cross-linking agent by mass percent, stirring, standing, filtering, cleaning and drying to obtain fire extinguishing agent emulsion particles;

Preparation of microcapsule fire extinguishing agent: adding the fire extinguishing agent emulsion particles into water, adding polysulfone solution during stirring, and then stirring, filtering, cleaning and drying to obtain the microcapsule fire extinguishing agent.

8. The method for preparing a microcapsule fire extinguishing agent according to claim 7, wherein the polymer material aqueous solution consists of 0.1% -5% sodium alginate aqueous solution by mass fraction and 0.8% gelatin aqueous solution by mass fraction; the mass ratio of the sodium alginate aqueous solution to the gelatin aqueous solution to the defoamer to the core material is 1: (0.3-3): (0.001-0.05): (0.05-0.3);

Dripping the fire extinguishing agent emulsion into 0.5-10% calcium chloride aqueous solution by mass percent for gelation reaction, and then standing, filtering and cleaning to prepare a rudiment of fire extinguishing agent emulsion particles; then placing the rudiment of the fire extinguishing agent latex particles in an aqueous solution of dialdehyde with the mass fraction of 0.1% -2%, standing for 12-48h, filtering, cleaning and drying to obtain the fire extinguishing agent latex particles;

The polysulfone solution is a dichloromethane solution of polysulfone with the mass fraction of 2% -10%; the mass ratio of the fire extinguishing agent latex particles to the water is 1: (7.28-30).

9. The method for preparing the microcapsule fire extinguishing agent according to claim 7, wherein in the preparation of the fire extinguishing agent emulsion, the stirring speed is 1000-3000r/min, the stirring time is 5-30min, and the temperature is 10-40 ℃;

In the preparation of the fire extinguishing agent latex particles, the rudiment of the fire extinguishing agent latex particles is placed in a dialdehyde water solution and then is kept stand for 12-48h at the temperature of-5-10 ℃.

10. Use of a microcapsule fire extinguishing agent according to any of claims 1-6, in passive fire extinguishing products and fire extinguishing products.