# US 2025/0152986 A1 · Foam stabilizing composition for fluorine-free firefighting foams > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2025/0152986 A1 - Document ID: US20250152986A1 - Status: Published application - Kind: A1 - Application number: 18/725,705 - Filed: 2022-12-30 - Published: 2025-05-15 - Earliest claimed: 2021-12-31 - Assignees: Dow Silicones Corporation; Dow Global Technologies LLC - Applicants: Dow Silicones Corporation; Dow Global Technologies LLC - Inventors: Anirudha BANERJEE; Zachary WENZLICK; Yusen QIAO - Web page: https://patentgrep.com/patent/US20250152986A1 ## CPC - A62D 1/0071: {Foams} - C08K 5/19: Quaternary ammonium compounds - C08K 5/544: containing nitrogen - A62D: CHEMICAL MEANS FOR EXTINGUISHING FIRES OR FOR COMBATING OR PROTECTING AGAINST HARMFUL CHEMICAL AGENTS; CHEMICAL MATERIALS FOR USE IN BREATHING APPARATUS - C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09) ## Abstract A foam stabilizing composition comprises (A) an anionic polymer and (B) a siloxane cationic surfactant comprising a cationic moiety having the formula Z1-D1-N(Y)a(R)2-a, wherein Z1 is a siloxane moiety, D1 is a divalent linking group, R is H or an unsubstituted hydrocarbyl group having from 1 to 4 carbon atoms, subscript a is 1 or 2, and each Y has formula -D-NR13+, where D is a divalent linking group and each R1 is independently an unsubstituted hydrocarbyl group having from 1 to 4 carbon atoms. An aqueous foam comprising the composition and method of using the same are also disclosed. ## Claims ### Claim 1 A foam stabilizing composition, comprising: (A) an anionic polymer; and (B) a siloxane cationic surfactant having general formula (I): [Z1-D1-N(Y)a(R)2-a]+y[X−x]n (I), wherein Z1 is a siloxane moiety; D1 is a divalent linking group; R is H or an unsubstituted hydrocarbyl group having from 1 to 4 carbon atoms; each Y has formula -D-NR13+, where D is a divalent linking group and each R1 is independently an unsubstituted hydrocarbyl group having from 1 to 4 carbon atoms; subscript a is 1 or 2; 1≤y≤3; X is an anion; subscript n is 1, 2, or 3; and 1≤x≤3, with the proviso that (x*n)=y; wherein at least one of the following provisos is true: (i) components (A) and (B) are present in the foam stabilizing composition in a weight ratio of from 0.5:1 to 3.5:1 (A)/(B); and/or (ii) components (A) and (B) are present in the foam stabilizing composition to provide a molar ratio of anionic groups in component (A) to cationic groups in component (B) of from 1:1 to 6.5:1; wherein component (A) is selected from sodium carboxy methyl cellulose, propylene glycol alginate, poly-D-galacturonic acid and its methyl ester, carboxymethyl dextran (sodium salt), and combinations thereof. ### Claim 2 (depends on 1) The foam stabilizing composition of claim 1, wherein proviso (i) is true. ### Claim 3 (depends on 1) The foam stabilizing composition of claim 1, wherein proviso (ii) is true, wherein the foam stabilizing composition further comprises water, and wherein a weight ratio of water to component (A) is from 90:1 to 600:1. ### Claim 4 (depends on 1) The foam stabilizing composition of claim 1, wherein: (i) the anionic polymer (A) comprises a polyelectrolyte polymer; (ii) the anionic polymer is soluble in water; or (iii) both (i) and (ii). ### Claim 5 (depends on 1) The foam stabilizing composition of claim 1, wherein the siloxane moiety Z1 has the formula: where each R3 is independently selected from R2 and —OSi(R4)3, with the proviso that at least one R3 is —OSi(R4)3; where each R4 is independently selected from R2, —OSi(R5)3, and —[OSiR22]mOSiR23; where each R5 is independently selected from R2, —OSi(R6)3, and —[OSiR22]mOSiR23; where each R6 is independently selected from R2 and —[OSiR22]mOSiR23; where 0≤m≤100; and where each R2 is independently a substituted or unsubstituted hydrocarbyl group. ### Claim 6 (depends on 1) The foam stabilizing composition of claim 1, wherein the siloxane moiety Z1 has one of the following structures (i)-(iv): ### Claim 7 (depends on 1) The foam stabilizing composition of claim 1, wherein: (i) D1 is a branched or linear alkylene group; or (ii) D1 has formula -D3-N(R7)-D3-, where each D3 is an independently selected divalent linking group and R7 is H or Y, where Y is independently selected and as defined above. ### Claim 8 (depends on 1) The foam stabilizing composition of claim 1, wherein component (B) has at least one of the following formulas: ### Claim 9 (depends on 1) The foam stabilizing composition of claim 1, further comprising (C) a stability enhancer other than component (B). ### Claim 10 (depends on 9) The foam stabilizing composition of claim 9, wherein a weight ratio of component (C) to component (B) is from greater than 0:1 to 10:1. ### Claim 11 (depends on 9) The foam stabilizing composition of claim 9, wherein the stability enhancer (C) has one of the general formulas (II) or (III): [Z2-D2-N(Y)b(R)2-b]+y[X−x]n (II), [(Z2-D2)c-N+(R)4-c]+y[X−x]n (III), wherein Z2 is a substituted or unsubstituted hydrocarbyl group or a functional group; D2 is a covalent bond or a divalent linking group; subscript b is 1 or 2; subscript c is 0, 1, 2, 3, or 4; and each R, Y, superscript y, X, subscript n, and superscript x is independently selected and as defined above. ### Claim 12 (depends on 11) The foam stabilizing composition of claim 11, wherein component (C) has formula (II) and wherein Z2 is an alkyl group having from 6 to 18 carbon atoms. ### Claim 13 (depends on 1) The foam stabilizing composition of claim 1, wherein: (i) each D1 is selected from —CH2CH(OH)CH2— and —HC(CH2OH)CH2—; (ii) each R1 is methyl; (iii) each X is Cl and superscript x is 1; or (iv) any combination of (i)-(iii). ### Claim 14 (depends on 1) An aqueous foam comprising water and the foam stabilizing composition of claim 1. ### Claim 15 (depends on 14) A method of extinguishing a fire comprising contacting the fire with the aqueous foam of claim 14.