Cross-Reference To Related Application

[0001] This application claims the benefit of priority of Singapore Patent Application No. 10201610879W, filed 27 December 2016, the content of it being hereby incorporated by reference in its entirety for all purposes.

Technical Field

[0002] The present disclosure relates to an aqueous composition for use in fire extinguishers. The present disclosure also relates to a method of producing such an aqueous composition for use in fire extinguishers.

Background

[0003] A common type of disaster that may result in loss of life and property is a fire. Depending on the scale and nature of a fire, it can be put out with the use of suitable firefighting equipment. One example of a firefighting equipment commonly used to put out small fires, which may be found in corporate offices, shopping malls, movie theatres or homes, is a portable fire extinguisher.

[0004] Fires may be classified based on the type of sources which the fire arises from, and various types of fire extinguishers have been designed to put out at least one class of fire. An example of classification may be as follows: class A refers to fuel source such as wood, paper and textiles, class B refers to flammable liquids, class C refers to flammable gases etc. Despite the various fire extinguishers available, there are a number of problems associated with conventional fire extinguishers.

[0005] One problem is that conventional fire extinguishers tend to contain harmful, though effective, fire extinguishing agents (e.g. toxic ingredients and/or volatile organic compounds) which cause secondary pollution or produce an adverse environmental impact when such conventional fire extinguishers are employed.

[0006] Another problem is that some types of conventional fire extinguishers, such as fire extinguishers that use traditional dry powder fire extinguishing agents, does not prevent the fire from re-igniting. [0007] Among the different fire extinguishers, the most commonly used agent is water. Water, in fire extinguishers, may be useful for tackling class A fire (paper, wood, straw etc.). Water, however, has its own shortfall. For example, water as an extinguishing agent is not as effective for class B and class C fires compared to powder extinguishing agents, and it is also not used for class E fire as water conducts electricity. Water also freezes in cold climate and may carry pollutants as run-off water. Despite this, water is considered as an efficient, cheap and readily available medium for use in extinguishing fires.

[0008] There is thus a need to provide for a water-based fire extinguisher that ameliorates and/or resolves one or more of the issues mentioned above. The provided water-based fire extinguisher should be easy to apply, environmentally acceptable and effective for extinguishing fires.

[0009] There is also a need to provide for a method of producing a water-based composition for use in fire extinguishers. The water-based composition should address one or more of the issues mentioned above.

Summary

[0010] In one aspect, there is provided for an aqueous composition for use in fire extinguishers, comprising:

an aqueous solution comprising one or more potassium salts;

a film forming agent comprising a fluorinated silane or a derivative of fluorinated silane;

at least one foaming agent comprising a non-ionic surfactant; and

water.

[0011] In another aspect, there is provided for a method of producing an aqueous composition for use in fire extinguishers, comprising:

adding at least one foaming agent comprising a non-ionic surfactant to an aqueous solution comprising one or more potassium salts to form a mixture; and

adding a film forming agent comprising a fluorinated silane or a derivative of fluorinated silane to the mixture. Brief Description of the Drawings

[0012] The drawings are not necessarily to scale, emphasis instead generally being placed upon illustrating the principles of the invention. In the following description, various embodiments of the present disclosure are described with reference to the following drawings, in which:

[0013] FIG. 1A shows different types of fire extinguishers based on different classes fires.

[0014] FIG. IB shows an example of where a conventional fire extinguisher is located. The left image shows a conventional fire extinguisher located under a seat while the right image shows a conventional fire extinguisher located along a corridor.

[0015] FIG. 2 shows a fire triangle, which is a simple model used to understand the components necessary for most fires. The triangle illustrates that a fire requires three elements, which are heat, fuel and oxygen. Detailed Description

[0016] The following detailed description refers to the accompanying drawings that show, by way of illustration, specific details and embodiments in which the invention may be practised.

[0017] Features that are described in the context of an embodiment may correspondingly be applicable to the same or similar features in the other embodiments. Features that are described in the context of an embodiment may correspondingly be applicable to the other embodiments, even if not explicitly described in these other embodiments. Furthermore, additions and/or combinations and/or alternatives as described for a feature in the context of an embodiment may correspondingly be applicable to the same or similar feature in the other embodiments.

[0018] The present disclosure relates to an aqueous composition for use in fire extinguishers. The present disclosure also relates to a method of producing such an aqueous composition for use in fire extinguishers.

[0019] Fire extinguishers play a critical role in protecting the environment by controlling fires at very early stages. A fire tends to require three basic elements. The three basic elements are heat, fuel and oxygen. Heat is needed for the ignition temperature, that is to say, the temperature required to start the fire. Fuel refers to the combustible material that serves as the source of the fire. Oxygen is needed to sustain combustion, i.e. to keep the fire burning. With these three basic elements, a fire may result. Based on such a model, a fire may be prevented or extinguished by removing any one of the three elements.

[0020] Accordingly, a fire extinguishing composition should be designed to tackle, at least one of these elements. An extinguishing composition of a portable fire extinguisher may cool burning fuel, displace and/or remove oxygen, and/or stop a chemical reaction so that the fire does not sustain or spread. In this regard, water may serve as one of the fire extinguishing agents. This is because when water changes from liquid to vapour state (steam), it absorbs vast amount of heat. This means that if applied correctly, water then reduces the temperature of the fuel to the point where the fuel is not giving off sufficient vapour for combustion process to continue. However, water when used alone has its own shortfall. For example, as mentioned above, water is not effective for class B, class C and class E fires. Therefore, conventional water-based extinguishers should be used with consideration in order to be appropriately applied to a fire situation.

[0021] The present aqueous composition and present method address one or more issues as mentioned above. The present aqueous composition, differs from conventional water-based fire extinguishing composition, in that it comprises water, a filming agent (i.e. a film forming agent), a foam stabilizer (i.e. a foaming agent), and a cooling agent. The film forming agent, as defined herein, refers to a chemical that forms a cohesive and continuous covering over a combustible material when applied to their surface in a fire, thereby cutting off air, especially oxygen, to extinguish the fire.

[0022] The present aqueous composition is advantageous in that it is non-toxic. It utilizes a fluorinated silane and/or derivative of a fluorinated silane to form a film over the combustible material to extinguish the fire. As the fluorinated silane and/or derivative of fluorinated silane dries out because of heat from the fire, it turns into a solid thin film coating the combustible substrate. The fluorinated silane and/or derivative of fluorinated silane makes the fire extinguishing composition more stable so that it can be diluted with tap water and/or sea water. The present aqueous composition is also advantageous in that it can be stored below 0°C without freezing. The present aqueous composition is a stable, low viscosity mixture with excellent fire extinguishing performance, which can be used to extinguish fires arising from polar and/or non-polar organic solvent. In addition, the present fire extinguishing aqueous composition used in fire-fighting and anti-burning system is capable of extinguishing fires effectively in harsh conditions (e.g. hot and cold climates).

[0023] A method of formulating a water-based fire extinguisher composition is disclosed in the present disclosure. The water-based fire extinguisher composition is formulated based on water, can be diluted by tap and/or sea water, can be diluted to 3 vol% to 6 vol% (e.g. three or six parts of the present aqueous composition diluted with 97 or 94 parts of water, respectively) without losing its effectiveness, can be used for extinguishing class A and class B fires, and prevents fire from further burning.

[0024] Having outlined various advantages of the present aqueous composition and the present method, definitions of certain terms are first discussed before going into details of the various embodiments.

[0025] The word "substantially" does not exclude "completely" e.g. a composition which is "substantially free" from Y may be completely free from Y. Where necessary, the word "substantially" may be omitted from the definition of the invention.

[0026] In the context of various embodiments, the articles "a", "an" and "the" as used with regard to a feature or element include a reference to one or more of the features or elements.

[0027] In the context of various embodiments, the term "about" or "approximately" as applied to a numeric value encompasses the exact value and a reasonable variance.

[0028] As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

[0029] As used herein, the phrase of the form of "at least one of A and B" may include A or B or both A and B. Correspondingly, the phrase of the form of "at least one of A and B and C", or including further listed items, may include any and all combinations of one or more of the associated listed items.

[0030] Unless specified otherwise, the terms "comprising" and "comprise", and grammatical variants thereof, are intended to represent "open" or "inclusive" language such that they include recited elements but also permit inclusion of additional, unrecited elements.

[0031] Details of the various embodiments are now described below. [0032] In the present disclosure, there is provided for an aqueous composition for use in fire extinguishers, comprising an aqueous solution comprising one or more potassium salts, a film forming agent comprising a fluorinated silane and/or a derivative of fluorinated silane, at least one foaming agent comprising a non-ionic surfactant, and water.

[0033] The aqueous solution comprising or consisting of the one or more potassium salts act as the cooling agent. This is because the addition of potassium salt in aqueous solution helps to reduce and depress the freezing point of the present aqueous composition. This allows the present aqueous composition to be stored below 0°C without freezing and also allows a cooling extinguishing composition to be applied to a fire. Accordingly, the present aqueous composition provides a cooling effect due to the intrinsic thermal properties of a cold material (i.e. the aqueous solution containing the one or more potassium salts), which cools a fire when injected into the flames. The potassium salt has another advantage in that they decomposed to release potassium ions, hydrogen, water and carbon dioxide in fire, thereby helping to extinguish the fire. The decomposition is endothermic and this augments the cooling effect provided by the one or more potassium salts. The breakdown of potassium salt has a further advantage in that it inhibits formation of free radicals and this breaks the support for combustion arising from a radical chain reaction. Such an advantage arises from the heterogenous recombination of active flame-propagating species such as the hydrogen, hydroxyl and oxygen radicals on the surface of the combustible material/combusted material or their homogeneous recombination via gas phase reactions catalyzed by potassium. Moreover, the water and carbon dioxide produced from the decomposition act as local oxygen diluents or inertants. Inertants, is defined herein to refer to any chemical substance that participates in a combustion reaction by capturing free radicals (e.g. hydrogen, hydroxyl and oxygen) that propagate flames.

[0034] In various embodiments, the one or more potassium salts may be about 5 weight percent to about 50 weight percent of the aqueous composition. The one or more potassium salts may be about 5 weight percent to about 20 weight percent, about 20 weight percent to about 50 weight percent, about 5 weight percent to about 12.5 weight percent, about 14 weight percent to about 18 weight percent, or about 13 weight percent, according to some embodiments. Any of the described amounts may be used as long as the resultant aqueous composition is stable and not costly.

[0035] In various embodiments, any potassium salt that provides for the above advantages may be suitable. In some embodiments, the one or more potassium salts may comprise or consist of potassium formate. In some embodiments, the one or more potassium salts may comprise or consist of potassium formate and potassium acetate. In some embodiments, the one or more potassium salts may comprise or consist of potassium bisulphate, potassium bromide, potassium carbonate, potassium chloride, potassium formate, potassium iodate and/or potassium nitrate. The use of one or more potassium salts may depress the freezing point of the present aqueous composition to below -20°C or even -30°C (e.g. potassium formate and potassium acetate).

[0036] The present aqueous composition includes a film forming agent comprising the fluorinated silane and/or the derivative of fluorinated silane. The advantage of such a film forming agent has been mentioned above. First, it forms a film covering the combustible material to cut off air, including oxygen, thereby diminishing fire. Second, it stabilizes the present aqueous composition and hence allows dilution with vastly available tap and/or sea water. The film forming agent comprising the fluorinated silane and/or the derivative of fluorinated silane may be about 2 weight percent to about 13 weight percent of the aqueous composition. The fluorinated silane and/or the derivative of fluorinated silane may be about 2 weight percent to about 12.5 weight percent, or about 4 weight percent or about 13 weight percent, according to some embodiments. Any of the described amounts may be used as long as the resultant aqueous composition is stable and not costly.

[0037] The fluorinated silane and/or the derivative of fluorinated silane, without being limited to, may be selected from the group consisting of 11- acetateundecyltriethoxysilane, 1 1-acetateundecyltrimethoxysilane, allyltrichlorosilane, allyltriethoxysilane, allyltrimethoxysilane, [3-(2- aminoethylamino)propyl]trimethoxysilane, 3 -aminopropyl(diethoxy)methylsilane, (3 - aminopropyl)trimethoxysilane, azidotrimethylsilane, 11-azidoundecyltriethoxysilane, 11-azidoundecyltrimethoxysilane, 3-[bis(2-hydroxyethyl)amino]propyl- triethoxysilane, bis(3-(methylamino)propyl)trimethoxysilane, 1 ,2- bis(trichlorosilyl)ethane, 1 ,6-bis(trichlorosilyl)hexane, bis(trichlorosilyl)methane, 1,2- bis(triethoxysilyl)ethane, 1 ,2-bis(trimethoxysilyl)ethane, bis[3-

(trimethoxysilyl)propyl] amine, (3 -bromopropyl)trichlorosilane, (3 - bromopropyl)trimethoxysilane, butyltrichlorosilane, tert-butyltrichlorosilane, chloromethyl(methyl)dimethoxysilane, (chloromethyl)triethoxysilane, chloromethyltrimethoxysilane, (3 -chloropropyl)trimethoxysilane, 3 - cyanopropyltrichlorosilane, 3 -cyanopropyltriethoxysilane, dichlorodiphenylsilane, diethoxydimethylsilane, diethoxydiphenylsilane, diethoxy(3- glycidyloxypropyl)methylsilane, diethoxy(methyl)phenylsilane, diethoxy(methyl)vinylsilane, [3-(diethylamino)propyl]trimethoxysilane, dimethoxydiphenylsilane, dimethoxy(methyl)octylsilane, dimethoxy-methyl(3 ,3 ,3 - trifluoropropyl)silane, dimethoxymethylvinylsilane, (N,N- dimethylaminopropyl)trimethoxysilane, dimethyl-di(methacroyloxy- 1 -ethoxy)silane, dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride, dimethyloctadecyl [3 -(trimethoxysilyl)propyl] ammonium chloride, N,N-dimethyl-4- [(trimethylsilyl)ethynyl]aniline, diphenylsilanediol, dodecyltriethoxysilane, ethoxydimethylphenylsilane, ethoxytrimethylsilane, ethyltrimethoxysilane, 3- glycidoxypropyldimethoxymethylsilane, 3 -glycidoxypropyldimethylethoxysilane, (3 - glycidyloxypropyl)trimethoxysilane, hexachlorodisilane, hexadecyltrimethoxysilane, hexadecyltrimethoxysilane, hexyltrimethoxysilane, (3 -iodopropyl)trimethoxysilane, isobutyl(trimethoxy)silane, (3 -mercaptopropyl)trimethoxysilane, 2-

(methacryloyloxy)ethyl [3 -(triethoxysilyl)propyl] carbamate, methoxy(dimethyl)octadecylsilane, methoxy(dimethyl)octylsilane, methoxytrimethylsilane, 2- { 3 - [ro-methylpoly(dimethylsiloxane)-a-yl]propoxy } ethyl {2-[(2-methylprop-2-enoyl)oxy]ethyl} carbamate, octamethylcyclotetrasiloxane, octenyltrichlorosilane, 1 H, 1 H,2H,2H-perfluorodecyltriethoxysilane, 1 H, 1 H,2H,2H- perfluorododecyltrichlorosilane, 1 H, lH,2H,2H-perfluorooctyltriethoxysilane, n- propyltriethoxysilane, p-tolyltrichlorosilane, trichloro [2-(chloromethyl)allyl] silane, trichlorocyclohexylsilane, trichlorocyclopentylsilane, trichloro(dichloromethyl)silane, trichloro(hexyl)silane, trichloro(octadecyl)silane, trichloro(octyl)silane, trichloro(lH,lH,2H,2H-perfluorooctyl)silane, trichloro(phenethyl)silane, trichloro(phenyl)silane, 3-(trichlorosilyl)propyl methacrylate, trichloro(3,3,3- trifluoropropyl)silane, trichlorovinylsilane, triethoxy(octyl)silane, triethoxyphenylsilane, 3-(triethoxysilyl)propionitrile, 3-(triethoxysilyl)propyl isocyanate, triethoxy vinylsilane, trimethoxy [3 -(methylamino)propyl] silane, trimethoxy(octadecyl)silane, trimethoxy(7-octen- 1 -yl)silane, trimethoxy(octyl)silane, trimethoxy [2-(7-oxabicyclo [4.1.0]hept-3-yl)ethyl] silane, trimethoxy(2- phenylethyl)silane, trimethoxyphenylsilane, trimethoxyphenylsilane, 3- (trimethoxysilyl)propyl acrylate, N- [3 -(trimethoxysilyl)propyl] aniline, Nl-(3- trimethoxysilylpropyl)diethylenetriamine, N- [3 -

(trimethoxysilyl)propyl]ethylenediamine, 3-(trimethoxysilyl)propyl methacrylate, 3- (trimethoxysilyl)propyl methacrylate, l-[3-(trimethoxysilyl)propyl]urea, N-[3- (trimethoxysilyl)propyl] -N'-(4- vinylbenzyl)ethylenediamine hydrochloride solution, trimethoxy (3, 3, 3 -trifluoropropyl)silane, 2-[(trimethylsilyl)ethynyl]anisole, tris[3- (trimethoxysilyl)propyl] isocyanuratej vinyltrimethoxysilane, vinyltrimethoxysilane, and their combinations.

[0038] In various embodiments, the aqueous composition may comprise at least one foaming agent. The term "foaming agent" may be used interchangeably with the term "foam stabilizer". The at least one foaming agent may comprise or consist of a non- ionic surfactant. The non-ionic surfactant may be a glycol based non-ionic surfactant. The non-ionic surfactant may be glycol. Non-limiting examples of the non-ionic surfactant include ethylene glycol, propylene glycol, diethylene glycol monohexyl ether, methoxytriglycol (triethylene glycol monomethyl ether), ethoxytriglycol (triethylene glycol monoethyl ether), butoxytriglycol (triethylene glycol monobutyl ether), diethylene glycol, polyethylene glycol, polyethylene glycol (also known as polyethylene oxide), triethylene glycol, ethylene glycol monophenyl ether, ethylene glycol monosalicylate, diethylene glycol butyl ether, ethylene glycol butyl ether, ethylene glycol-bis(2-aminoethylether)-N,N,N',N'-tetraacetic acid, poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol), tetraethylene glycol, poly(propylene glycol), dipropylene glycol, poly(ethylene glycol) methyl ether, hexylene glycol, diethylene glycol dimethyl ether, di(ethylene glycol) ethyl ether, hexaethylene glycol, diethylene glycol monoethyl ether, poly(ethylene glycol) dimethacrylate, pentaethylene glycol, triethylene glycol monomethyl ether, diethylene glycol diethyl ether, tripropylene glycol, ethylene glycol diethyl ether, di(ethylene glycol) vinyl ether, tetraethylene glycol dimethacrylate, ethylene glycol monopropyl ether, poly(ethylene glycol) methyl ether acrylate, tri(ethylene glycol) monoethyl ether, tetraethylene glycol dimethyl ether, diethylene glycol methyl ether, poly(ethylene glycol) dimethyl ether, triethylene glycol monobutyl ether, methoxypolyethylene glycol amine, diethylene glycol dibutyl ether, poly(propylene glycol) acrylate, pentaethylene glycol monododecyl ether, di(propylene glycol) methyl ether, methoxypolyethylene glycol maleimide, diethylene glycol monoethyl ether acetate, polyethylene glycol monomethyl ether mesylate, tetraethylene glycol monododecyl ether, poly(propylene glycol) methacrylate, poly(propylene glycol) dimethacrylate, poly(ethylene glycol) methyl ether amine, triethylene glycol monooctyl ether, octaethylene glycol monohexadecyl ether, pentaethylene glycol monooctyl ether, decaethylene glycol mono-dodecyl ether, methoxypolyethylene glycol, and o-(2- aminoethyl)polyethylene glycol. The foaming agent also helps to cool the fire and coat the fuel, preventing its contact with oxygen, thereby suppressing combustion.

[0039] In various embodiments, the at least one foaming agent comprising the non- ionic surfactant may be about 0.05 weight percent to about 14 weight percent, about 0.05 weight percent to about 13 weight percent, about 2 weight percent to about 14 weight percent, about 0.05 weight percent or about 0.06 weight percent, about 1 weight percent, about 12.5 weight percent, or about 4 weight percent, of the aqueous composition. Any of the described amounts may be used as long as the resultant aqueous composition is stable and not costly.

[0040] Apart from the glycol based non-ionic surfactant, the foaming agent may contain an alkoxylated ammonium alkyl sulphate, such as ammonium lauryl ether sulphate. In some embodiments, the at least one foaming agent comprises an alkoxylated ammonium alkyl sulphate and the glycol based non-ionic surfactant. In some embodiments, the at least one foaming agent comprises ammonium lauryl ether sulphate and the glycol based non-ionic surfactant. The alkoxylated ammonium alkyl sulphate, when diluted with water, yields a foam which extinguishes fires.

[0041] In various embodiments, the present aqueous composition comprises water. The water may be about 60 weight percent to about 99 weight percent, or about 70 weight percent of the aqueous composition. Any other amount of water may be added to the other components to sum up to 100 wt%. Any of the described amounts may be used as long as the resultant aqueous composition is stable and not costly. [0042] The present disclosure also provides for a method of producing an aqueous composition for use in fire extinguishers, comprising adding at least one foaming agent comprising a non-ionic surfactant to an aqueous solution comprising one or more potassium salts to form a mixture, and adding a film forming agent comprising a fluorinated silane and/or a derivative of fluorinated silane to the mixture.

[0043] Various embodiments of the present aqueous composition, and advantages associated with various embodiments of the present aqueous composition, as described above may be applicable to the present method, and vice versa.

[0044] In various embodiments of the present method, adding the at least one foaming agent may comprise dissolving the one or more potassium salts in water. The one or more potassium salts may comprise or consist of potassium acetate and/or potassium formate. Advantages of adding one or more potassium salts have been described above. In some embodiments, dissolving the one or more potassium salts comprise dissolving the one or more potassium salts in an amount which forms about 5 weight percent to about 50 weight percent of the aqueous composition. The one or more potassium salts may be dissolved in an amount which forms about 5 weight percent to about 20 weight percent, about 20 weight percent to about 50 weight percent, about 5 weight percent to about 12.5 weight percent, about 14 weight percent to about 18 weight percent, or about 13 weight percent, according to some embodiments. The amount used should result in a stable aqueous composition that is not too costly.

[0045] In various embodiments, adding the at least one foaming agent may comprise adding a glycol based non-ionic surfactant in an amount which forms about 0.05 weight percent to about 14 weight percent, about 0.05 weight percent to about 13 weight percent, about 2 weight percent to about 14 weight percent, about 0.05 weight percent or about 0.06 weight percent, about 1 weight percent, about 12.5 weight percent, or about 4 weight percent, of the aqueous composition. The amount used should result in a stable aqueous composition that is not too costly. Non-limiting examples of the glycol based non-ionic surfactant have been described above. In some embodiments, the at least one foaming agent comprising the non-ionic surfactant may comprise or consist of ethylene glycol. That is to say, the glycol based non-ionic surfactant may be ethylene glycol. [0046] In some embodiments, adding the at least one foaming agent may comprise adding an alkoxylated ammonium alkyl sulphate and the glycol based non-ionic surfactant in an amount which forms about 0.05 weight percent to about 14 weight percent, about 0.05 weight percent to about 13 weight percent, about 2 weight percent to about 14 weight percent, about 0.05 weight percent or about 0.06 weight percent, about 1 weight percent, about 12.5 weight percent, or about 4 weight percent, of the aqueous composition. In some embodiments, adding the at least one foaming agent may comprise adding an ammonium lauryl ether sulphate and the glycol based non-ionic surfactant in an amount which forms about 0.05 weight percent to about 14 weight percent, about 0.05 weight percent to about 13 weight percent, about 2 weight percent to about 14 weight percent, about 0.05 weight percent or about 0.06 weight percent, about 1 weight percent, about 12.5 weight percent, or about 4 weight percent, of the aqueous composition.

[0047] In various embodiments of the present method, adding the film forming agent may comprise adding the film forming agent comprising the fluorinated silane and/or the derivative of fluorinated silane in an amount which forms about 2 weight percent to about 13 weight percent, about 2 weight percent to about 12.5 weight percent, or about 4 weight percent or about 13 weight percent, of the aqueous composition.

[0048] In various embodiment, the fluorinated silane and/or the derivative of fluorinated silane, without being limited to, may be selected from the group consisting of 11-acetateundecyltriethoxysilane, 11-acetateundecyltrimethoxysilane, allyltrichlorosilane, allyltriethoxysilane, allyltrimethoxysilane, [3-(2- aminoethylamino)propyl]trimethoxysilane, 3 -aminopropyl(diethoxy)methylsilane, (3 - aminopropyl)trimethoxysilane, azidotrimethylsilane, 11-azidoundecyltriethoxysilane, 11-azidoundecyltrirnethoxysilane, 3-[bis(2-hydroxyethyl)amino]propyl- triethoxysilane, bis(3-(methylamino)propyl)trimethoxysilane, 1,2- bis(trichlorosilyl)ethane, l,6-bis(trichlorosilyl)hexane, bis(trichlorosilyl)methane, 1,2- bis(triethoxysilyl)ethane, 1 ,2-bis(trimethoxysilyl)ethane, bis[3-

(trimethoxysilyl)propyl] amine, (3 -bromopropyl)trichloro silane, (3 - bromopropyl)trimethoxysilane, butyltrichlorosilane, tert-butyltrichlorosilane, chloromethyl(methyl)dimethoxysilane, (chloromethyl)triethoxysilane, chloromethyltrimethoxysilane, (3 -chloropropyl)trimethoxysilane, 3 - cyanopropyltrichlorosilane, 3-cyanopropyltriethoxysilane, dichlorodiphenylsilane, diethoxydimethylsilane, diethoxydiphenylsilane, diethoxy(3- glycidyloxypropyl)methylsilane, diethoxy(methyl)phenylsilane, diethoxy(methyl)vinylsilane, [3-(diethylamino)propyl]trimethoxysilane, dimethoxydiphenylsilane, dimethoxy(methyl)octylsilane, dimethoxy-methyl(3 ,3,3- trifluoropropyl)silane, dimethoxymethylvinylsilane, (N,N- dimethylaminopropyl)trimethoxysilane, dimethyl-di(methacroyloxy- 1 -ethoxy)silane, dimethyloctadecyl [3 -(trimethoxysilyl)propyl] ammonium chloride, dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride, N,N-dimethyl-4- [(trimethylsilyl)ethynyl]aniline, diphenylsilanediol, dodecyltriethoxysilane, ethoxydimethylphenylsilane, ethoxytrimethylsilane, ethyltrimethoxysilane, 3- glycidoxypropyldimethoxymethylsilane, 3 -glycidoxypropyldimethylethoxysilane, (3 - glycidyloxypropyl)trimethoxysilane, hexachlorodisilane, hexadecyltrimethoxysilane, hexadecyltrimethoxysilane, hexyltrimethoxysilane, (3-iodopropyl)trimethoxysilane, isobutyl(trimethoxy)silane, (3 -mercaptopropyl)trimethoxysilane, 2-

(methacryloyloxy)ethyl [3-(triethoxysilyl)propyl]carbamate, methoxy(dimethyl)octadecylsilane, methoxy(dimethyl)octylsilane, methoxytrimethylsilane, 2- { 3 - [ro-methylpoly(dimethylsiloxane)-a-yl]propoxy } ethyl {2-[(2-methylprop-2-enoyl)oxy]ethyl}carbamate, octamethylcyclotetrasiloxane, octenyltrichlorosilane, 1 H.1 H,2H,2H-perfluorodecyltriethoxysilane, 1 H, 1 H,2H,2H- perfluorododecyltrichlorosilane, 1 H, 1 H,2H,2H-perfluorooctyltriethoxysilane, n- propyltriethoxysilane, p-tolyltrichlorosilane, trichloro[2-(chloromethyl)allyl]silane, trichlorocyclohexylsilane, trichlorocyclopentylsilane, trichloro(dichloromethyl)silane, trichloro(hexyl)silane, trichloro(octadecyl)silane, trichloro(octyl)silane, trichloro(l H, 1 H,2H,2H-perfluorooctyl)silane, trichloro(phenethyl)silane, trichloro(phenyl)silane, 3-(trichlorosilyl)propyl methacrylate, trichloro(3,3,3- trifluoropropyl)silane, trichlorovinylsilane, triethoxy(octyl)silane, triethoxyphenylsilane, 3-(triethoxysilyl)propionitrile, 3-(triethoxysilyl)propyl isocyanate, triethoxyvinylsilane, trimethoxy[3-(methylamino)propyl]silane, trimethoxy(octadecyl)silane, trimethoxy(7-octen- 1 -yl)silane, trimethoxy(octyl)silane, trimethoxy[2-(7-oxabicyclo[4.1.0]hept-3-yl)ethyl]silane, trimethoxy(2- phenylethyl)silane, trimethoxyphenylsilane, trimethoxyphenylsilane, 3- (trimethoxysilyl)propyl acrylate, N- [3 -(trimethoxysilyl)propyl] aniline, Nl-(3- trimethoxysilylpropyl)diethylenetriamine, N- [3 -

(trimethoxysilyl)propyl]ethylenediamine, 3-(trimethoxysilyl)propyl methacrylate, 3- (trimethoxysilyl)propyl methacrylate, l-[3-(trimethoxysilyl)propyl]urea, N-[3- (trimethoxysilyl)propyl]-N'-(4-vinylbenzyl)ethylenediamine hydrochloride solution, trimethoxy(3,3,3-trifluoropropyl)silane, 2-[(trimethylsilyl)ethynyl]anisole, tris[3- (trimethoxysilyl)propyl] isocyanurate, vinyltrimethoxysilane, vinyltrimethoxy silane, and their combinations.

[0049] The present method may further comprise stirring the mixture at a temperature of 25°C to 35°C for 2 hours to 6 hours after adding the film forming agent comprising the fluorinated silane or the derivative of fluorinated silane. The stirring duration may be 4 hours.

[0050] The present method may further comprise diluting the mixture with water to obtain a low viscosity fire extinguishing composition that is sufficiently fluid for use in a fire extinguisher. Low viscosity allows the present aqueous composition to spread rapidly to cut off the combustible material from the fire, heat and/or oxygen. The use of water to form the present aqueous composition renders it more cost effective.

[0051] While the methods described above are illustrated and described as a series of steps or events, it will be appreciated that any ordering of such steps or events are not to be interpreted in a limiting sense. For example, some steps may occur in different orders and/or concurrently with other steps or events apart from those illustrated and/or described herein. In addition, not all illustrated steps may be required to implement one or more aspects or embodiments described herein. Also, one or more of the steps depicted herein may be carried out in one or more separate acts and/or phases.

Examples

[0052] The present disclosure relates to an aqueous composition for use in fire extinguishers. The present disclosure relates to a method of producing such an aqueous composition.

[0053] The present disclosure, according to some embodiments, includes formulation of a water-based fire extinguisher agent. The water-based fire extinguishers may comprise a mixture of fluorinated silane [about 13 weight percent (wt%)], (b) one or more fluorinated surfactants (about 1 wt%), (c) a cooler (i.e. cooling agent or coolant) (about 13 wt%), (d) water (about 60 wt% to about 99 wt%) and (e) other additives (about 1 wt%). The values and ranges as provided are independent of each other, meaning that the amount of each component may be chosen to add up to a sum of 100 wt%. In some embodiments, the present aqueous composition may comprise about 4 wt% film former (i.e. film forming agent), about 4 wt% foaming agent (i.e. surfactant), about 14 wt% to 18 wt% potassium salt and 74 wt% to 78 wt% water.

[0054] The conventional gasoline fire test results (Fire Rating Type 55B and 13 A), as described in one of the examples below, demonstrate that the present aqueous composition is excellent for use as a water-based fire extinguisher agent with its excellent fire extinguishing performance. The test results indicated that the present aqueous composition meets the requirements and specifications of fire test in the absence of traditional dry powder fire extinguisher.

[0055] The present aqueous composition and the present method are described in the examples below.

[0056] Example 1: Comparison of Conventional Fire Extinguishers

[0057] A comparison of conventional fire extinguishers with respect to class A and class B fires are shown in table 1 below. Based on table 1, conventional fire extinguishers may not be environmentally sustainable (e.g. exerts a negative environmental impact when used) and may employ harmful agents in their composition (e.g. toxic ingredients such as volatile organic compounds). Conventional fire extinguishers may not be balanced in terms of their fire extinguishing efficiency and cost. That is to say, they may be both costly and inefficient for extinguishing fire, or they may be efficient but costly, or they may not be costly but inefficient. The present aqueous composition and method address one or all of these concerns. [0058] Table 1 - Comparison of Conventional Fire Extinguishers For Class A and Class

B Fires

[0059] Example 2: Method of Producing the Present Aqueous Composition

[0060] An example of the present method of producing the present aqueous composition is described as follows.

[0061] First, raw material KCOOH (100 g) was added to 500 mL of tap water and stirred to dissolve completely. Subsequently, 0.5 g of commercially available surfactant ammonium lauryl ether sulfate, 100 mL of ethylene glycol and 100 mL of fluorinated silane were added. The resulting suspension was stirred at room temperature for 4 hours, and then diluted for further use.

[0062] Example 3: Fire Extinguishing Testing

[0063] The concentrated solution, the present composition prepared before dilution, may be diluted with tap water or sea water to produce a low viscosity fire extinguisher composition. Three or six parts of the concentration was diluted with 97 or 94 parts of water (i.e. 3% and 6%, respectively).

[0064] The diluted fire extinguisher agent was then applied to class A and B fires for testing, based on combustible materials of wood fire and spilled flammable liquids in a pool or body of liquid, respectively, which was ignited. The fuel used was petrol and kerosene, about 15 to 25 litres for the test pan. The test standard is based on Fire Rating Type 55B and 13 A.

[0065] During the testing, when the handle of an extinguisher is compressed, it opens an inner canister of high pressure gas that forces the extinguishing composition out to produce a low density inflated foams. These bubbles rapidly spread on the surface of the combustible material (e.g. hydrocarbon fuel or other flammable liquid body), forming a thin film on the surface. When the film is disturbed or destroyed, it regenerates to segregate the hot steam from the combustible material (e.g. flammable liquid), thereby extinguishing the flames. The potassium salts reduce the temperature of the combustible material by decomposing to release potassium ions and carbon dioxide in the fire, resulting in a break in support combustion of a radical chain reaction.

[0066] The following is another non-limiting example for illustration of the testing and the testing results.

[0067] In another testing, the concentrate was diluted with 97 parts of seawater to form a premix. The premix was filled into a canister, which was pressurized with compressed air to 10 psi (68.9476 kPa). 1 -square-foot (0.0929-square metre) test disc was loaded into water and heptane, and then ignited and allowed to burn for 10 seconds. The foam produced from the air delivery nozzles was applied to the heptane flame after 10 seconds. Table 2 below shows the fire test results.

[0068] Table 2 - Fire Test Results

[0069] Based on the conventional gasoline fire test (Fire Rating Type 55B and 13 A) performance results as described above, it is demonstrated the present water-based fire extinguisher composition can replace some, if not all, conventional fire extinguishers such as traditional dry powder fire extinguishers, in applicable instances. [0070] Example 4: Additional Characterization Results - Biodegradability, Toxicity and Density

[0071] The biodegradability, toxicity and density of the present aqueous composition produced based on the present method were also evaluated. Their results are presented in tables 3 to 5 below.

[0072] Table 3 - Results of Biodegradability Test

* Adjustable to about pH 7

[0073] APHA is a standard method for determination of water and waste water.

[0074] Table 4 - Results For Toxicity

[0075] Table 5 - Results For Density

[0076] The density measurement for the samples were carried out. Multiple replicates of measured volume of the liquid samples were weighed, and the weights determined were divided by the volumes used.

[0077] Example 5: Commercial and Potential Applications

[0078] The manufacturing of the present aqueous composition for use in water-based fire extinguishers is simple, efficient and cost effective, and it works in both hot and cold zones. This helps to fulfill the market demand for water-based fire extinguisher agents in Singapore and overseas market. The present aqueous composition, and its method of production, possess the potential to replace traditional dry powder fire extinguisher in some applications.

[0079] Advantageously, the present aqueous composition and method are able to utilize tap and sea water to form an improved stable water-based fire extinguishing composition (composition does not lose its effectiveness when mixed with tap or sea water). Such a composition is anti-freezing in that it can be stored at freezing point of water or below (e.g. -20°C) without solidifying. It is safe to use, non-toxic and biodegradable. It can exert a cooling effect and prevent fire from further burning. It can also be diluted to 3 vol% to 6 vol% without loss of effectiveness and efficiency and this implies cost saving since treated water is not essentially required. An example of the present aqueous composition for use in fire extinguishers is shown in table 6 below. The values shown for each component in table 6 are independent of each other. That is to say, the potassium salt may be 5 wt% to 12.5 wt% of the aqueous composition, and the other components add up to a sum forming 100 wt%. To illustrate on this, one example may be 12.5 wt% of fluorinated silane, and together with the other ingredients, add up to a sum forming 100 wt%. In another example, the present aqueous composition may contain 12.5 wt% of potassium salt, 12.5 wt% of fluorinated silane while surfactant and water tops up to a sum forming 100 wt%. The ratio of ingredients may be adjusted.

[0080] Table 6 - An Example of the Present Aqueous Composition

Ingredient Weight Percentage (wt%) Function

Potassium Salt 5 to 12.5 Cooling agent

Fluorinated Silane 2 to 12.5 Film forming agent

Ethylene glycol about 12.5 Foaming agent

Surfactant (e.g.

Ammonium lauryl 0.06 Foaming agent ether sulphate)

Water 60 to 99 Cooling agent [0081] Advantageously, fluorinated silane is non-explosive. In the present aqueous composition, it is needed as the polymeric film forming agent, which is stably integrated with the other components. Fluorinated surfactants such as fluorotelomers, perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) may be used to form the present aqueous composition.

[0082] The present aqueous composition may be stored safely at 20°C to 70°C without flashing and precipitating of its constituents. The shelf life is at 6 months or more for the various temperatures, e.g. room temperature. The present aqueous composition does not have a flashpoint. The use of fluorinated silane and/or its derivative as an ingredient to formulate a fire extinguishing composition provides for the advantages as mentioned above.

[0083] The present aqueous composition, including its method, may be applicable for use in sprinkler systems, cargo ships or freighters, car fire extinguishers, fire extinguisher balls and kitchen extinguishers.

[0084] While the invention has been particularly shown and described with reference to specific embodiments, it should be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. The scope of the invention is thus indicated by the appended claims and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced.