JPS5854969A - Fire fighting agent for polar solvent - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an aqueous fire extinguishing foam composition that is particularly effective against fires caused by polar solvents as well as non-polar solvents.

Various foam extinguishing agents have been developed for non-polar solvent fires such as gasoline, kerosene, light oil, heavy oil, and crude oil.
When these are applied to polar solvent fires such as Alpur, ketones, esters, ethers, amines, etc., the water in the foam film is taken away by the polar agitating agent, causing the foam to collapse instantly or become very weak, resulting in almost no Cannot exert fire extinguishing effect.

For this reason, protein foam fire extinguishers and synthetic interfacial foam fire extinguishers are currently mainly used to fight polar solvent fires. Dilute these concentrated extinguishing agent solutions with water,
When foaming occurs immediately, metal soap precipitates on the surface of the foam film and acts as a barrier to polar solvents, making the foam difficult to destroy and allowing it to float on the liquid surface and spread, leading to extinguishing the fire. .

However, these have the following serious defects. That is, if it is not used within 2 to 3 minutes after being diluted with water at a fire station, it will form a precipitate in the water stream, which will significantly reduce its fire extinguishing effectiveness. Furthermore, since the foam does not have sufficient solvent resistance, the foam disappears quickly. Therefore, when injecting bubbles to the combustion liquid surface, it is necessary to do so very quietly and in a large amount. For this reason, special measures are required in the design and installation method of the foam outlet, resulting in the need for a large amount of extinguishing agent and a long time to extinguish the fire. For example, in the case of a methanol fire, it takes a long time to extinguish the fire because the foam can only be developed after the methanol is diluted to about 75-80% with the extinguishing chemical, and because a large amount of extinguishing agent is injected, the tank is full. When extinguishing a fire in a nearby solvent tank, there is a risk that the solvent will overflow.

In order to overcome these disadvantages, aqueous film-forming fire extinguishing foams based on fluorosurfactants have high chicken tropism and water bathability.When they come into contact with polar solvents, they are dehydrated at the interface and become water bathable polymers. Forms a gel-like mat of material that covers the surface of the burning liquid and protects the foam above it, helping to extinguish the fire.
．． It is believed that Therefore, this extinguishing agent has better foam expandability than metal soap-type extinguishers, and its extinguishing effect is improved. As expected, alcohols (isopropyl alcohol,
It has no fire extinguishing effect on solvents that produce a large amount of combustion heat or are highly volatile, such as t-pole//-le, etc.), ketones, and propylene oxide.

In addition, this extinguishing agent requires a large amount of a chicken-tropic water-soluble polymer substance, so the stock solution has a very high viscosity (4 o
o.

est or higher), and therefore the viscosity changes with temperature, which makes it difficult to handle in practice. Furthermore, even during storage, there is a risk that a thin layer (skin) will form on the tank wall and liquid surface, making it difficult to store long and narrow. If the concentration of the chicken-tropic water bathing polymer substance is lowered, a gel-like mat will not be formed or will become weaker, so a dilution ratio of 6% or more is required. Historically, this extinguishing agent has a high freezing temperature of around 0°C and is not reversible in freezing and thawing, so special consideration is required when using or storing it at low temperatures. As is clear from the above points, this extinguishing agent has many drawbacks.

In order to solve the above problems, the present inventors carried out research on Eido, and as a result, discovered a % heterogeneous interaction between an anionic hydrophilic group-containing surfactant and a cationic water-soluble polymer substance, and discovered that The inventors discovered that an aqueous fire extinguishing foam based on the mixture forms extremely stable foam not only in nonpolar solvents but also in polar solvents, leading to the completion of the invention.

That is, the present invention is envisioned to be an aqueous fire extinguishing foam that contains an anionic hydrophilic group-containing surfactant and a cationic water-soluble polymeric substance and is capable of forming a tough, stable, and flame-resistant foam. .

The anionic hydrophilic group-containing surfactant used in the present invention is one that can electrostatically interact with a cationic water-soluble polymer substance, and in this - taste, the cough surfactant is anionic and hydrophilic. It is essential to have at least one group. As anionic hydrophilic group, 100OH, -80,H,
-080,H, -0PO(OH).

A group such as the like is preferable, and a group having an inorganic or organic cation as a counter ion of the anionic group may also be used.

The surfactant may contain one or more anionic groups of the same type or different types as a hydrophilic group, and may also contain one or both of a cationic hydrophilic group and a nonionic group in addition to the anionic parent group. Amphoteric ionic surfactants may also be used.

The hydrophobic group of the surfactant includes an aliphatic hydrocarbon group having 6 or more carbon atoms, a dihydrocarbyl polysiloxane chain, and a 6-carbon aliphatic hydrocarbon group.
~20 fluorinated aliphatic groups or a combination of these in one molecule may be used. Further, the surfactant may be a mixture of various compounds having different hydrophobic groups.

Specific examples of the anionic hydrophilic group-containing interfacial viscosity agent particularly useful in the present invention include the following.

C11HgCOC11H,CM,N(CH3COONa
)tCtyHssCONH(CH,J((CH,),
80. Na)sC4eC,F,,80. N(C,H,
)CH,C00KCIFI? 80! N(C,H,)C
M,CH,080,NaC,F,,C0N(C,Hly
) (CM Ri, So, N & C, F,, 80-stone (CHt
)sN (CHs) (CH,)s80mNmC8F1
．． So,NH(CIl[z)mN(CHtCH,CO
The cationic water-soluble polymer substance used in the present invention contains a primary, secondary, or tertiary amino group, ammonium group, pyridinium group, or quaternary ammonium group in the main chain or side chain, and Solubility in n, 13ml
1% or more. The polymerization degree of the polymer is regulated by its solubility in water, but polymers ranging from oligomers to polymerization degrees of tens of thousands or more can be used.

Specific examples of cationic water-soluble polymeric substances particularly useful in the present invention include the following.

Polyethyleneimine Copolymer of ethyleneimine and ethylene oxide Melamine-formaldehyde condensate Guanidine-formaldehyde condensate The specific synergistic effect on the foam properties of the anionic water group-containing surfactant and the cationic water-bathable high monomer tJiIJ5Q is as follows: It is observed over a wide range of allocation ratios of both components. The preferred range of the blending ratio of the cationic water-based polymeric substance to the anionic water-based surfactant varies depending on the combination of both components, and it is difficult to specify both components, but in general, the weight ratio ( LO5-50, more preferably 0.1
~10. If the blending ratio of the cationic water-soluble polymeric substance is too low, the complex formed between the anion and the hydrophilic group-containing surfactant becomes water-insoluble, significantly impairing foamability. Even if the compounding ratio is above the upper-favorable range, the synergistic effect will not prevent dust generation, but the viscosity of the extinguishing agent stock solution or diluted solution will increase significantly, and the commercial value will be impaired.

The specific synergistic effect according to the present invention is maximized in the pH range of 6 to 8. It is desirable that the extinguishing agent be used in a pH range of weakly acidic to weakly alkaline from the viewpoint of safety to the human body, living things, etc., corrosivity of storage containers, etc., and the usefulness of the composition of the present invention is also confirmed from this point of view. .

The fire extinguisher of the present invention has excellent layer resistance and long-term storage stability in both diluted and undiluted states. Due to the composition's excellent solubility and low viscosity, a concentrated stock solution with a high dilution ratio can be easily produced. The kinematic viscosity of the 3% diluted stock solution can be kept below 100 centistokes at 20°C, and has excellent practical handling properties. In addition, since only a small amount of cationic water-soluble polymer material is added, the freezing point of the stock solution can be raised to 100% without deteriorating performance.
It has the characteristic that it can be easily lowered to between ℃ and -20℃.

In the fire extinguishing agent of the present invention, in addition to the surfactant component and the water-soluble polymer, additives for each electrode may be added as necessary. Additional foam stabilizers, freezing point depressants, as additives
Examples include rust preventives, pH11i1 adjusters, and the like. Additional foam stabilizers are mainly added to adjust the foaming ratio of 4'' and include nonionic surfactants, cationic surfactants, polyethylene glycol, polyvinyl alcohol, etc. Freezing point depressants include ethylene glycol. , propylene glycol, selonrugs, calpitols, lower alcohols, urea, etc. As rust preventives and pH adjusters, various agents well known in the industry can be used.

The extinguishing agent of the present invention can be prepared in a known manner, namely by using air, carbon dioxide,
It is applied by blowing or mixing with nitrogen, low boiling fluorocarbons such as difluorodichloromethane, or other suitable non-flammable gases.

When the fire extinguishing agent of the present invention is stored as a concentrated undiluted solution, it is diluted to a dilution of '1' by the usual method, for example, by sucking it into a water stream on the way to a fire extinguishing device or foam nozzle, and extinguishing it with non-flammable gas such as air. Foaming can be achieved by blowing or mixing, and can also be achieved by blowing or pumping the foam above or below the entrance surface.

The fire extinguishing agent of the present invention can be used in combination with a powder fire extinguishing agent, a protein foam fire extinguishing agent, a foam fire extinguishing agent for wood fires, etc.

Next, the present invention will be further evaluated and explained by Examples. In the following examples, all percentages refer to it percentages.

Example 1 CsF+tBoz NH(CHe)sN(Gim)(C
HJsSOaNa 5”f.

Polyethyleneimine (Mw 40,000-70,000) 6% ethylene glycol 15% butylcarpitol 15% water
59% These mixtures were stirred at room temperature to obtain a clear solution. A trace amount of 1 to this:
i HCI was added to adjust the pH to z5 by 1 lJlnll.

The properties of the obtained extinguishing agent (6% type stock solution) are shown in fi-IK.

Example 2 Polyethyleneimine (My 40,000 to 70,000) 6% ethylene glycol 15% butyl calpitol 15% water
59% These mixtures were stirred at room temperature to obtain a clear solution. Add a small amount of 1
: IH (J) was added to adjust the pH to 15. The properties of the obtained fire extinguisher (5% type stock solution) are shown in Table 1.

Example 6 CsFty 5OkNH(CHc)sN(CHeCOO
Na)t 5% polyethyleneimine (M
W40,000-70,000) 6% ethylene glycol
15% Butyl Calpitol
15% water
51% These mixtures were stirred at room temperature to obtain a clear solution. Minor prize 1: Add IHCj to this and adjust the pH.
was adjusted to z5. The properties of the obtained extinguishing agent (3% type stock solution) are shown in Table 1.

Table-1 The results for the stock solution are shown.

Next, Examples 1 to 60 of the fire extinguishing agent of the present invention
A fire extinguishing experiment was conducted based on the method described in No. 6. As a comparative example, an experiment was also carried out using a chicken-tropic water-soluble polymer compounded fire extinguisher (containing a fluorosurfactant, a commercially available product). The outline of the experimental method is as follows.

For the fire scale, a B-20 model with a combustion area of 2-2 was used, and 2,001 cm of fuel was charged. The pre-combustion time was 5 minutes. After diluting the extinguishing agent stock solution with fire extinguishing water, it was filled into a pressure-resistant container, and foam was supplied to the surface of the combustion liquid through a standard foaming nozzle for testing water-forming foam extinguishing agents at a pressure of 10 and 51 A. Discharge speed 101/M.

The total ejection time was 5 minutes. The results are shown in Table-2.

Claims (1)

[Claims] t A polar dissecting water-based fire extinguishing foam that contains an anionic hydrophilic group-containing surfactant and a cationic water-soluble molecular substance and is capable of forming a tough, stable, and flame-resistant foam. agent. 2 The anionic hydrophilic group-containing surfactant contains 1000-, -80;, -080;, -0PO as anionic hydrophilic group.
The extinguishing agent according to Claim 1JA, which is an amphoteric surfactant containing (OH)O or a combination thereof and also a cationic parent group. 5. The aqueous fire extinguishing foam according to claim 1, wherein the anionic hydrophilic group-containing surfactant is a fluorine-containing surfactant having a fluorinated aliphatic group having 6 to 20 fluorinated atoms as a hydrophobic group.