CA1102652A

CA1102652A - Method of improving fluorinated surfactants

Info

Publication number: CA1102652A
Application number: CA293,998A
Authority: CA
Inventors: Robert A. Falk; Paul C. Nicolson
Original assignee: Ciba Geigy Investments Ltd
Current assignee: BASF Schweiz AG
Priority date: 1976-12-30
Filing date: 1977-12-28
Publication date: 1981-06-09
Also published as: AU3199477A; BR7708741A; GB1591292A; FR2376208B1; DE2758013A1; MX148221A; CH634873A5; FR2376208A1; DE2758013C3; DE2758013B2; GB1591293A; JPS5385787A; NL7714204A; BE862459A; AU517771B2; JPS6254533B2; DE2759790C2

Abstract

METHOD OF IMPROVING FLUORINATED SURFACTANTS

Abstract of the Disclosure Surface properties of solutions of fluorinated surfactants are improved by employing a fluorinated synergist (Rf)nTmZ
wherein Rf is a perfluorinated aliphatic group, T is alkylene, arylene, alkylenethio alkylene, alkyleneoxyalkylene or alkyleneiminoalkylene, Z is a neutral or a polar group, n is 1 or 2 and m is 0 to 2, and/or a magnesium salt. The resulting synergistic surfactant compositions are useful for all appli-cations where surfactants are employed.

Description

Numerous surfactant applications depend on the attainment of low surface tensionsO Whereas conventional hydrocarbon surfactants can attain surace tensions of as low as 23 dynes/cm, fluorinated surfactants are unique in that they can attain surface tensions of 15-20 dynes/cm, and at best of 14.5 dynes/cm. Such extremeLy low surface tensions are, however, only reached at high concentrations of fluorinated surfactants and only with highly specific struc-tures. Since fluorinated surfactants are exceedingly expensive, it is imperative that the lowest surface tension is attained with the minimum quantity of surfactants.
- The problem of attaining the lowest possible surface tension with fluorinated surfactants has been the subject of innumerable patents and publications, which detail specific and idealized structures having such properties.
In all cases the preferred candidate surfactants have distinctive and highly spccific structures, which if varied even slightly dr~htic~lly alter the attainable surface tensions.
A fundamental reason that the attainment of a minimal sur-face tension at the lowest practicable use level is not easily answered is that the surface tension decreases as the fluor-inated tail increases, while the solubility generally decreases so markedly when even one -CF2- group is added that preci-pitation of the sparingly soluble fluorosurfactant frequently occurs.
It has long been known that the surface tension of

- 2 ~

: .. . .
, , , , ...... ., :
, " : , : .
. , ~ ,.; ~;

~ 52 hydrocarbon surfactants, which at best is 26-27 dynes/cm, can be depressed to 23 dynes/cm with sparingly soluble alco-hols. In fact, ~he adventitious nature of this effect is 50 marked that surface tension curves of conventional commercial surfactants frequently have minima unless the surfactant is scrupulously purified.
Bernett and Zisman, J. Phys. Chem., 65, 448 (1961), teach that synergistic mixtures of conventional hydrocarbon surfactants and fluorinated l,l-dihydro alcohols can be pre-pared which attain low surface tensions with smaller concen-trations of the fluorinated agent. The resultant solutions are, however, unstable and the fluorinated alcohols are, moreover, volatile and acidic. With the ammonium salt of a perfluoro-nonaoic acid, the fluorinated l,l,-dihydroalcohols are not sufficiently soluble and eventually form gelatinous preci-pitates.
In a urther effort to prepare better surfactants the prior art suggested preparing magnesium salts of anionic perfluorinated surfactants (Shinoda et al, J. Phys. Chem., 76, 90g (1972)~ and magnesium salts of hydrocarbon anionic sur-fac~ants (Reichenberg, Trans.~Faraday Soc., 43, 467 (1947)).
It was found, however, that when a magnesium salt is added to an aqueous solution of a fluorinated surfactant, preferably an anionic fluorinated surfactant, a further substantial lower-ing of the surface tension of the solution results. The aqueous solutions may contain further ingredients such as .. .. ..
: , , ~. .

., . .. . :.~.. :~. : , -..

Z

fluorinated synergists.
The ~nstant invent~on is directed to a method of im-proving the surface tension prvperties of solutions of cationic, anionic, non-ionic, amphoteric or mixed function fluorinated surf~ctan~s charac~erised in th~ to s~id surfactant solu-tions at le~st one of the component (1) ~ fluorinated synerg~st of the formula f )n mZ

wherein R~ is ~ straight or ~r~nched cha~n perfluo~alkyl of 1 to ~8 car~on ~tom~ or s~id perfluoroalkyl subst~tut~d by perfluoroalkoxy of 2 to 6 carbon ~toms, n i9 an integer of 1 or 2, T is a divalent group -R3- or a group -R3SCH2CHRl-~here R3 is str~i~ht or branched chain ~lkylene or halo-alkylene of 1 to 12 carbon atoms, arylene of 6 to 12 carbon atoms, alkylenethioalkylene or alkyleneiminoalkylene of 2 to 12 carbon atoms, where in said imino group the nitrogen atom is secondary or tertiary and Rl is hydrogen or alkyl of 1 to 12 carbon atoms, Z is a neutral or a polar group selected from -CONRlR2, 1 2' S2NRlR2~ R3~2CRl) and -C02Rl where R
and R~ ar~ independently hydrogen, alkyl of 1 to 12 carbon atoms or alkyl substituted with one or more -OH, -COCH3, -SHr -CONH(CH3), and R3 is as defined abover m ls an integer rom O to 2~ the fluori~ated synerglst 4~-~ .

. . ~

has solubility in water at 25C below 0.01% by weight, and ~:
component (2~ a magnesium salt is added In one preferred embodiment of the present invention the 1uorinated synergist only is added to the solution of the 1uorinated surfactant.
Other objects of this invention are the method for im-proving the surface tension properties of anionic fluorinated surfactant solutions by adding to said solutions a magnesium salt or by adding this magnesium salt together with the fluorinated synergist.
The surface tension of cationic, anionic, non-ionic amphoteric or mixed function fluorinated surfactants is im-proved by the use of a fluorinated synergist regardless of the specific structure of the surfactant. For the purpose of illustration the fluorinated surfactants can be represented by the general formula ~Rf)nAmQ

wherein Rf, n and m are as defined above and Q is a water solubilizing group wh~ch is an anionic, cationic, non-ionic or amphoteric moiety, or a combination of such moieties, A is a multivalent linking group, preferably a di-valent group such as alkylene o~ 1 to 12 and preferably of 1 to 4 carbon atoms; arylene, alkyl substituted phenylene or the group C6H5YC6H5 where Y is alkylene oE 1 to 4 and prefer ably methylene, oxygen or sulfur, sulfonamidoalkylene or _ 5 _ carbonamidoalkylene.
Typical anionic groups of Q axe carboxylic, ammonium or metal carboxylate where the metal is an alkali or alkali earth metal, especially sodium, potassium, calcium, magneslum and the like, sulfinic or sul~onic acid group or ammonium or a metal salt thereof or phosphonic (OP(OH)2) or phosphoric (OP(OH)3) acid group or ammonium or metal salt thereof. Typical cationic groups of Q are -N~12, -NHR where R is lower alkyl of 1 to 4 carbons, NR3X where ~ is hydrogen or lower alkyl and X is an anion such as a halogen, especially chloride, sulfate, phosphate, hydroxyl etc. Typical non-ionic groups of Q are amine oxides and groups derived from polyethylene oxide and mixed polyethylene oxide- polypropylene oxide polyols. Typical amphoteric ~nd mixed groups are respectively -N(CH3)2C2H4CO2, -N(CH3)(C2H4CO2H)~t O and the like. As to the mixed group sur-factants it is meant those of fluorinated surfactants which within the same molecule contain anionic and catio,lic moieties or anionic and non-ionic moieties or cationic and non-ionic moieties or cationic and amphoteric moieties or anionic and amphoteric moieties or non-ionic an amphoteric moieties. The above mentioned classes of fluorinated surfactants are also exemplified in German Offenlegungsschrift No. 2 656 677.
A is a multivalent linking group, preferably a di-valent group such as ~lkylene of 1 to 12 and preferably of 1 to 4 carbon atoms; arylene such as phenylene, alkyl e.g~ of 1 to 4 carbon atoms substituted phenylene or the group - - ~ ., ~:: ` . , ' 5;~ ~

C6H5YC6H5 where Y is alkylene of 1 to 4 and preferably methylene, oxygen or sulfur; sulfonamide alkylene, carbon-amidoalkylene and the like.
The Rf group can be, as stated above, broadly a per-fluoroalkyl of 1 to 18 carbons, but preferably it is a per-fluoroaliphatic of 5 to 12 carbon atoms.
It should be noted that in some instances more than one Rf group may be bonded to a single Q group and in other instances, a single R~ group may be linked to more than one Q group, or any be linked by a single Q group to more than one polar solubilizing group, The synergist component terminates in a covalently bonded group -T Z which is not critical as such. However, the overall solubility property as determined by the interrelation-ship of the moieties Rf, T and Z are important in establish-ing the effectiveness oE the synergist. It is generally neces-sary that the combination of the fluorinated radical and the terminating group be so balanced that the solubility of said synergist in water at 25C is minimal~ generally below 0.01%
by weight. In the case of Rf-surfactant/Rf-synergist composi-tions~ the solubility of the composition should be at least 0.1% by weight and in order to function affectively as a use-ful composition should provide a surface tension below 28 dynes/cm, preferably below 23 dynes/cm in aqueous/solvent solu-tion, -' The Eluorinated synergistic compound generally has - . , , ~ .

.

z a very limited solubility in water, but an enhanced solu-bility in the presence of the fluorinated surfactant. The critical aspect of the invention is that diverse fluorinated surfactants can be used for purposes of the invention which do not have idealized surface active properties. The syner-gistic additive effectively permits the resultant compositions to have markedly superior surface properties.
Consequently, the major component of these compo-sitions may be a fluorinated surfactant which is chosen not on the basis of unique surface properties but on the basis of its economic feasibility of synthetic availability. In fact, it may contain a mixture of fluorinated telomer derived end groups from C4F9- to C14F29-, be derived from fluorinated surfactants with highly branched tails, which do not generally exhibit good surf~ce propexties, or may contain some degree of hydrogen or chlorine substitution.
Because the synergistic additive is neutrai, it is compatible with anionic, cationic, non-ionic or amphoteric structures, all of which give compositions with improved pro-perties. This permits ~he choice of a fluoroc~emical surfactant type for an application indeRendent of its surface properties and more nearly based on its price and availability.
The fluorochemical synergists are generally inexpen-sive and are readily attainable fluorochemical derivatives.
They too may contain a mixture of fluorinated telomer derived end groups from C4F9- to C14F29-, but preferably the lower, .. . . . . .... . . . ..

65~:

more soluble homologs. While the synergists can have diverse functionalities, the most effective synergists are neutral yet contain highly polar functions and most preferably polar functions that can be solubilized by hydrogen bonding.
Strongly acidic or basic, corrosive or volatile, or otherwise unstable fluorochemical derivatives are not recommended as synergists for purposes of this invention.
This invention is also directed to a method of lower~
ing surface tension of an aqueous solution of an alkali metal salt of an anionic fluorinated surfactant by adding thereto ~rom 0.1 to 5 equivalents per equivalent of said anionic sur-factant of a magnesium salt consisting of magnesium sulfate, magnesium nitrate, magnesium chloride and magnesium acetate.
Although all above listed magnesium salts are very effective in lowering the surface tension, magnesium sulfate is preferred from economic and corrosion standpoint. Also ~fom the economic (cost/performance) standpoints it is pre-ferable that the magnesium salt is used in the amount of 1 to 4 equivalents per equivalent of the anionic surfactant, and most preferably in the amount of 1.5 to 2.5 equivalents.
Furthermore, the magnesium salt lowers the surface tension most effectively if the surfactant solution employed distilled or deionized water or low hardness water, that is, water con-taining less than 5 mg/l of minerals, in other words~ having less than 5 ppm ~parts per million) of minerals.
The method of this invention is efective especially _ g _ . .,. ,, . , ~ .

with fluorinated anionic surfactants, regardless of the chemical structure. Preferred anionic fluorinated sur~actants are carboxylic acids and salts thereof, sulfonic acids and salts thereof, phosphonates, phosphates, related phosphoro derivatives and salts thereof.
A further object of the present invention is the aqueous surfactant composition having improved surface proper-ties which contains a mixture of a cationic anionic, non-ionic, amphoteric or mixed function fluorinated surfactant and at least one of component (1) a fluorinated synergist of the for-mula (Rf ) nTmZ
wherein R~ is a straight or branched chain perfluoroalkyl of 1 to 13 carbon atoms or said perfluoroalkyl substituted by perfluoroalkoxy of 2 to 6 carbon atoms, n is an integer of 1 to 2, T is a divalent group -R3- or a group -R3SCH2CHRl-where R3 is straight or branched chain alkylene or halo-alkylene of 1 to 12 carbons, arylene of 6 to 12 carbons, alkylenethioalkylene or alkyleneiminoalkylene of 2 to 12 car-bons where in said imino groùp the nitrogen atom is secondary or tertiary and Rl is hydrogen or alkyl of 1 to 12 carbons, Z is a neutral or a polar group selected from -CONRlR2, -CN, -CONR, -COR2, -S02NRl, -R3(02CRl) and ~C02~1 where Rl and R2 are independently hydrogen, alkyl of 1 to 12 - ~ , ................ .
: ,, . .: ~ .

carbons or alkyl substituted with one or more -OH, -COCH3, -SH, -CONH(CH3), and R3 is as defined above, m is an integer from O to 2, the fluorinated synergist has solubility in water at 25~C below 0.0l% by weight, and component (2) a magnesium salt.
~f special interest are those compositions which con-tain a mixture of said 1uorinated surfactants and the fluorinated synergists, or a mixture of an anionic fluorinated surfactant and a magnesium salt or a mixture of an anionic fluorinated surfactant, a fluorinated synergist and a magnesium salt.
Further preferred are those compositions which con-tain an alkali metal salt of the anionic fluorinated sur~
factant and O.l to 5 equivalents per equivalent of the sur-factant of a magnesium salt consisting of magnesium sulfate, magnesium nitrate, magnesium chloride and magnesium acetate In these compositions magnesium sulfate is the most suitable species.
The resultant fluorinated synergist/fluorinated sur-factantlmagnesium salt compositions described in this inven-tion can be used advantageously in place of conventional fluorinated suractants for all purposes for which said con-ventional fluorinated surfactants are recommended. Naturally, various synergist/surfactant mixtures will be preferably for special considerations. For example, while cationic or anionic r surfactant derived compositions may exhibit special sub~

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, .. .. .. . :, . . ~ :
,~,. ,. , : , :: : .. . . .

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stantivity, amphoteric or non-ionic fluorosurfactants may be more preferably for compatibility with the overall formulation.
Thermal or hydrolytic stability considerations may lead to ~he choice of particularly stable functionalities for bo~h synergist and surfactant~ e.g. acid plating haths; non-ionic surfactant derived compositions may have special utility in non-aqueous or low foaming for~ulations; cationic surfactant derived compositions may be particularly synergistlc with disinfectants. These examples are merely exemplary of the synergistic compositions, and preferred compositions should be chosen with due regard to the actual application. These compositions, just as concentional fluorochemical surfactants, are useful to improve or impart properties such as wetting, penetrati~n, spreading, levelling, foam stabilityg flow pr~-perties, emulsification, dispersion, and oil and water re-pellency. Based on these unique properties are numerous appli-cations, some of which fol~ow. Although applications are sug-gested for a particular use area, the general applicability of each c~ncept is inferred for other applications.

.

Plastics and Rubber Industry Emulsifying agent for polymerization, particularly fluoro-~onomers As a latex stabilizer To aid in the preparation of agglomerates of powdered fluoro-carbon polymers Ir synergistic mixtures with hydrocarbon surfactants to wet low energy surfaces including natural and synthetic rubbers, resins, plastics . As an adjuvant for foam applications and as foaming agents to aid in leak detection . As a foam additive to control spreading, crawling, edge buildup . A5 a mold release agent for silicones, etc.
. In refractory processes . As an antimist film former . Additive for elimination of trapped alr in plastic laminates . Wetting agent for resin molds for definition, strength . Hot- melt additive for oil and grease repellency . Resin ac!ditive for improved wetting of and bondin~ with fillers . Flow modifier for extruding hot melts: spreading, uniformity, anticratering . Adjuvatlt for resin etchant . Mold release agent, demolding agent . Retarder for plasticizer migration or evaporation . Internal antistatic agent for polyolefins . Antiblocking agent for polyolefins Petroleum Indus try . Wetting assistant far oil well treatments, drilling muds . As a film evaporation inhibitor for gasoline, jet fuel, solvents, hydrocarbons . iubricating, cutting ~il improve~, to improve penetration times . In extreme pressure lubricants . Oil spill collecting agent . Additive to improve ter~iary oil well recovery ..
. . ;. ..

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Textile and Leather Industries .
. Soil release and soil proofing agent . Oil/water repellent textile and leather treatment . Wetting agent to improve coverage and penetration of pores of substrates . Antifoaming agent in textile treatment baths . Wetting agent for finish-on-yarn uniformity . Penetrating agent for finishes on tow, heavy denier fibers . Emulsifying agent/lubricant for fiber finishes . Cleaner/metal treating agent for polymerization equipment . Flow modifier for spinning of hot melts, solutions . Additive for fabric finishes for spreading, uniformity . Wetting agent ~or dyeing . Penetration aid for bleaches , Wetting ~gent for binder in nonwo~en fabrics Pain~ Pi~ment and F _ishin~ Industries Levelling, anticraterin~ adJuvant for finishes and paints Adjuvant for control of soiling . ~gent to control differential evaporatlon of solvents . Leveling agent for floor waxes . Adjuvant for waxes to improve oil and water repellency . Adhesion improver for oily or greasy surfaces . To combat pigment flotation problems . Improver for automotive finishes, based on water-based coatings in which the pigments are rendered nonreactive D Pi gment grinding aid to promote wetting, dispersion, color development :` ` ` ' ,, ~ ` ' : .: . .:, .,. , ~ !
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. Foam generator substance for the application of dyes, inks . Electrolytic conversion coatings Minin~ and _eta1__Working _ dustries . In cleaning agents for property improvement . Additive for solvent cleaning . Additive for metal pickling baths to increase bath life and acid runoff . Additive for chrome electroplat;ng: surface tension reduction, foaming . Additive for soldering f1ux, especially for electronic circuitry . Protective agent for coatings (tarnish resistance, grease repellency) . Corrosion inhibitor . Additive for etchant solution for improved definition . To form antimist films and anticondensation surfaces . Plastic preplate and silicon etchant technology . In soldering flux for microelectronics to reduce foamillg . In chemical roughing agent ~olutions, prior to galYanization . ~s a colloidal dispersion aid for magnetic solids . Protective coatings for aluminum and as an antiblocklng agent . Wetting agent for leaching copper ores and as a froth flotation agent O To promote ore ~etting and quicker breaking of the protective oxide layer Pharmaceutica1 Industry . Improve the properties and penetration of antimicrobial agents ., , . , .
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.
; ; .. ,... ~ , .. , . : -. Improve the properties of biochemicals, biocides, algicides, bacteriocides and bacteriostats . Lmprove the strength, homogeneity, and reduce the permeability of encapsulated materials . Emulsify fluorochemical blood substil:utes Agriculture and Forestry . Wetting agent for herbicides, fungicides, weed killers, hormone grow~h regulators, parasiticides, insecticides, germicides, bactericides, nematocides, microbiocides~
defolients and fertilizers . As an ingredient in chemosterilents, insect repellents and toxicants . For wettable powder pesticides and chemical powders . Corrosion inhibitor for chemical applicators . Wetting agent for foliage . Wetting additive for live stock dips, or to wet sheep skins during desalination . Wetting adjuvant for manufacture of plywoood veneer . Penetrant for preservative impregnation . Pulping aid . For cleaning tubes in paper making, dyeing . Grease/oil repellents for paper ~ ` '.
. Wetting agent for fighting forest fires . Ingredient of AFFF, aqueous film forming extinguishing agents (foams) . Component of fluoropxotein foams . . .
. Additives to dry chemical extinguishing agents .,, . . "

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3~2 . Agent in aerosol-type extinguishers . Wetting agent for sprinkler water Automotive, Building Maintenance and Cleanin~
. Wetting agent for cleaning compositions . Additive for alkaline cleaners . Glass cleaner . Wetting agent for automobile waxes . Adjuvant to improve oil/water repellency o~ wax . Lubricant/corrosion inhibitor for antifreeze . Rinse-aid for car washes . In dry cleaning compositions and solvent cleaners, for wa-ter displacement and foaming, May improve soil suspension and decrease redeposition . Foaming agents for pipe cleaning . Anti-mist film foamer for glass and plastics . In foams for dust suppresion . Cleaner for building exteriors . For acidic concrete cleaners , Air entrainment additive for low densi~y concrete . Bubble foamer for air tracing, in ventilating systems Household, Cosmetic and Personal Products . Rinse-aid for dishwashing . Liquid polishing compositions . Floor polish levelling agent . Additive for alkaline oven cleaners - . . .
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"``: ::` " '' ' . Synergistic improver for disinfectants . Carpet cleaners . Synergistic wetting agent in detergent formulations . Additive Eor protec~ive coatings on metals (tarnish resistance, grease resistance) . Gloss and antistatic improver . Hair shampoo ingredîent . Shaving foam ingredient . Oil and water repellent cosmetic powders ingredient . Ingredient of lotions or creams for skin or hair . Ingredient of skin proteetion creams Photography and Graphic Arts . Printing ink additive for ink flow and levelling, both aqueous and solvent based . Wetting agent for writing inks . To combat pigment flooding and flotation in printing inks O To form ink repellent surfaces for waterless lithoplates, or electrographic coatings . Prevent reticulation of gelatin layers and improve uni-formity . Assist in film drying . Improve film coatings and reduce `'contraction flecks"
. Wetting, levelling, anti-cratering assist agent . Surfactant for developer solutions . Photoemulsion stabilizer . Prevent photo-lubricant agglomeration . Coating aid in the preparation of multiple layer film elements ! . .

' . . . , ' , 6~Z

. An~istatic wetting agent for film coatings . Antifogging agent for films . Bonding agent for fillers and fluoropolymer ~ilms . In coatings for nematic liquid crystal cells Illustrative examples of Rf-anionics which can be used ln the compositions of this invention are the below shown acids and their alkali metal salts. Preferred anionic groups are carboxylate and sulfona~e. The anionic surfactant should generally contain 30-65% of carbon bound fluorine in order to attain suitable solubility properties The anionic surfactant may be present as free acid, an alkali metal salt thereof, ~m~onium, or substituted ammonium. The following patent numbers appearin~ in parenehesis are patents which more fully disclose the represented class of compounds.

Carboxylic Acids and Salt~ thereof R~COOH (Scholberg e~ al, J. Phys. Chem. 57, 923-5 ( lg53) Rf(CH2)1-20C~I (Ger. 1,916,669) Rf(c~2)2_20cooH (Ger. 2,132,164) R~O(CF2)2_20(cH2)2-2oc (Ger. 2,132,164) Rf(cH2)l_20cooH (U-S. 3,409,647) RfS02N(C2H5)CH2COOH (U.S. 3,258,423) ~O(CF20)3cF2coo~ (Fr. 1,531,902) .. : . . ,, , .~, . ~ ; ; . .: .
. .

. : ; ,: , : : :
..

i5 RfO(CF2CF~ C~2COOH . ~:Fr. 1,5371922 . 3~3 R~O~CF(CF3)CF2O]CF(CF3)CON(CH3) C~l2COOH (U.S. 3,7~B,265) 1 2 5)2~ 3) 2 ~Brit. 1,176,493) loFl9oc6~4coN~cH3)cH2cooH (Brit. 1,270,662) f (CH2)1_3SCH(COO'-i)C~2COO~1 ~U.s. 3,706,787) f(cH2)l-l2s(c~2)l-l7cooEl Ger. 2,239,~09;
U.S 3,17~,910 sulfonic-Acids and Salts Thereof ~, , ' Rfs03H (U.S. 3,475,333) ~Ger. 2,134,973) ~(CH2)1_20sO3 - ~Ger. 2,309,365) ~2NHCH2c6H4s3H ~Ger. 2,315,326) R~SO2N~c~3)~c2H4O)l-2o 3 (S.A. 693,583) RfCH2CH2OCH~CH2CH2SO3H (Can. 842,252) f ~ 4 3 . (Ger~ 2,23Q,366) C12F23OC6H4SO3H . (Ger. 2 240,263) (C2F5)3CO(CH2)3S03H ~Brit. 1,153 J 854) CF3(C2F5)2cO(cH2~3s 3 (Brit; 1~153,854) ( 2 5)2(cF3)ccH=c(cF3)so3H (Brit. 1,206,596) R~OCF(CF3)CF2OCF(cF3~CONHcH2so3H ~U.S. 3,798,265) Rf(CH2)lOor 2(C2H4)l 12 SO3H (Ger. 2,31~,426) `

Phosphonates, Phosphates, Related Phosphoro Derivatives, and Salts Thereof RfPO~OH)2 (Rf~2PO(OH) ~Ger. 2,110,767) SO2N(Et)C~H~OPO(OH)2 (Ger. ~,125,836) RfC~2OPO(OH)2 ~Ger~ 2,15~,661) C8F15Oc6H4cH2po(OH)2 ~Ger~ ~,215,387) RfOc6H4cH2po(o~)2 (Ger. 2,230,366) Others (and Salts Thereof~
; - - . ' `
RfS2N(C~3)C2H4S3H (Ger. 1,621,107) f 6 4 (U.S~ 3,475,333) f(CH2)l-2os2o3Na - (Ger. 2,115,139) f 2)l-~o~o2~(cH3)c~2c~2s2o3Na (Ger. 2,115,139) Rf~ 2H ~U~S. 3,562,156) ' Illustrative examples of Rf-cationics and X-amphoterics which can be used in the compositions of this in~ention are described in Table la and lb, but also include compounds more fully disclosed in the following patents, United States ~ -.
2~727,923, 2,759,019, 2,764~602, 2,764,603, 3,1~7,0659 3,207,730, 3,257,407, 3,510,494, 3,630,951, 3,681,413, 3~681,441g 3,759,981, 3~766,274j 3,828,~85, 3~839,425, 3,933,819, 3,941,705, 3,~S7,657 ... .

. . i. , ::.-., . :: . , :, , . , , . ., .: . , -, . ,~ . , . :. :

,,:

i2 German _.
1,925,555, 2,013,104, 2,119,302, 2,1207868, 2,127,232, 2,132,164, 2,165,057, 2~215,387, 2,219~642, 2,224,653, 2,230,366, 2,236,729, 2,239,709, 2,315~326, 2,325,855, 2,337~638, 2,357,916, 2,438,868, 2,523~402 British 1,270,662, 1,28~,678, 1,289,436 French 2,035,589, 2,128,028 Belgium 788,335, 801,585 Illustrative examples of Rf-nonionics which can be used in the compositions of this invention are described in ~able ld, but also include compounds more fully disclosed in the following patents.
United States . .
2,723,9~9, 3,621,059, 3,721,700, 3,883,596, 3,952,075, 1,925,555, ~,966,708, 2,160,852, 2,215,386 erman 2,2I5,388, 2,230,366, 2,244,028, 2,250,718, 2,325"355 2,334,346, 2,337,~38, 2,501,239 British ~,130,822, 1,148,~86, 1,155,6~7, 1,176,492 Belgium Netherlands Japanese . .
817,369 7,009,980 75-157,275 - ~2 -- ~ :, . . .

Illustrative examples o~ R~synergists which can be used in the compositions of this invention are given in ~able 2 and also include:

8F17S02N ~C2~5 ) CH2CHOH[CH;20EI
8 17 02N(CH3)CH2CHOHCH~OH
C8F17S02N~cH2cH20H~2 C8F17S02N(cH2cH2sH)2 0H

C8F17S02N~cH3)cloH2ocH2 C7F15CON ~C2H5)CH2CE~20H
CF3C6FloS02N tC2H5 ) CH2CH2 :~
3 70(C3F60)2CF2CON(CH3)C3H60H
C8F17S2NtCa,Hg)CH2CEIO~HCH20 C F CO-N/~ 2 C8F17S02N[CH2CH2CON(CH3)H]2 .

Also (c2F5~2(cF3)ccH2co~(R~cH2cH2oH wherein P~ is H, CH3, C2H5 or CH2CH20H disclosed in British Patent Specifi-fication No. 1,395,751; Rf(cH2cFRl)mcH2cH2cN wherein RI = H or F, m o 1-3 as disclosed in British Patent Sp~cl-fication No. 1,429,279; and compounds of the general structure: Rf-CH2CH2-SOxCmH2mA as described in German Patent Publication No. 2,344,889 wherein x is 1 or 2, R~
is as described above, m is 1 to 3 and ~ is carboxyllc ester, carboxamide or nitrile.

' ,~ ' : - ~3 - ~
~, . .: ., . . ., . . .. : , , ~ ,:

: ., : ~ . :: . : .
. . , . , . . : . .:, ~ , . ..
.;. -:- : ~, ~

: -:. . . :: ;.. :: . . ;:
. . .

-Experimental Part Tables la through ld list R~- anionic, amphoteric, cationic, and nonionic surfactants and Table 2 lists Rf-synergists which are used in the examp:Les following the tables.The commercially available surfactants used in the examples are:
F-l, which is an alkali metal salt of a perfluoroalkylsul-fonic acid F-2~ which is a perfluoroalkanesulfonamido alkylenemono-carboxylic acid salt as disclosed in U.S. ?~809,990 F-3, which is a cationlc quaternary ammonium salt derived from a perfluoroalkanesulfonamidoalkylenedialkylamine as disclosed in U.S. 2a759,019~ e.g.

C~F17S02NHC3H6N(cH3)3 F-4, which is a nonionic perfluoroalkanesulonamido poly~
alkylene oxide derivative F-5 and F-6, anionics derived from linear perfluoroalkyl telomers F-7, an amphoteric carboxylate derived from linear per-fluoroalkyl ~elomers F-8, a cationic qua~ernary`ammonium salt derived from linear perfluoroalkyl telomers F-9, a nonionic derived from linear perfluoroalkyl telomers F-10 und F 11, anionics derived from branched tetrafluoro-, .. - . ,~ , .,~, ,,,, . , , , ,, . , ~. . ..
, ,,: , .

. .

ethylene oligomers as disclosed in GB 1,148,486 F-12, a ~ationic derived from branched tetrafluoroethylene olig~mers as disclosed in DT 2,224,653 F-13, a nonionic derived from branched tetrafluoroethylene oligo~ers as disclosed in Brit. Pat. 1,130,822, 1,176,492 and 1,155,607 .

: Table la Fluorinate~ Anionic .Ir ~c~ nts used in Examples 1 to 9S

~f~ .
Surfa~tant Name Formula Al 2-Methyl-2-(3-[1~1,2,2-tetra- RfCH2CH2SCH2CH2CONHC(CH3)2CH2SO3Na hydroperfluoroalkylthio pro- wherein: 'C6Fl3 %CsFl7 %CloF
pionamide)-l-propanesulfonic . acid, scdium saltl . 39 41 13 A2 as aboYe . 44 4? 10 A3 as a~ove . 52 35 A4 as above - 60 36 4 A5 as above. . 32 42 21 A6 as above . 27 44 23 A7 as above 20 48 26 A8 as above, 45% ~00 A9 as above, 45% 100 A10 as above9 100~ ~ . 100 All2 1,1,2,2-Tetrahydroper~luoro-RfCH2CH2SO3 K
alkylsulfonate, potassiumwherein: 20 4~ 20 salt .
Al22 Perfluoroalkanoic acid, potassium salt R~COOK 32 62 ... .. .. ... ... , ._ .. " . .... . . ... .. . .. .. . .. .. . . .
-. . ,.. , -, : ; . .. ... . . ..
i ' i"': ' ,, , - .

.

Table la (Continuation) R~-Sur- _ _ . . --factant Name Formula ~ _ _ .__ _ . __ A13 A8, magnesium salt V/v~6Fl3 100 ~
A14 F-l A17 F-6 ::

Al9 F-10 A20 C8F17S02N(c2Hs)cH2co2 A21 , C8Fl7S3K

_ ~
. . Rf is a mixture consisting principally of C6F13, C8~17~ and - CloF21 in the approximate ratio 2:2:1 or as stated. 35V/o solu-~tion in 17.5% hexylene glycol - 47.5% water or as otherwise stated.
Approximate homolog distribution ,. ~ . .. . . . . . . , ,, ,, ,. , ,,, , :
. . . . , . ::, , . ,, ., .. . . - . .

Table lb . Fluorinated Amphoteric Surfactants used in Examples 1 to 9 . .

Surfactan~ Name or Formula For~ula _ .. _ __ . ..................... _ ~ _ A23a N-[3-(dimethylamino)propyl]-2 and 3- XC6Fl3 %CgFl7 %CloF
(1,1,2,2-tetrahydroperfluoroalkylthio) succinamic acid, 60% solids 32 36 22 ., A23b ditto ` 3g 41 - 13 . ; ,`' .
A23c d~tto 44 42 10 A24 C6Fl3S02N(CH2C ~)C3H6N(CH3~3 A25 C~Fl3cH2cH2sc~2cH2& CH3)2CH2C02 A26 C8F~7c2H~coNH(cH2)3~(cH3)2cH2cH2co~3 A27 C6Fl3S02N(C3H650~ C6H6~(CH3)z(c2H40H) A28 C8F17CH2CH~C ~)~(CH3)3 A29 C6Fl3S2N(CH2CH2C0~ C3H6~(cH332cH2cH2oH
. ~ .
A30 F- 14 (Du Pont) C7Fl5coNHcaH~(cH3~2cH2cH2co2 ~. .
~ ~ . :............... . .. . .. .
. ~, , , . :
, , . ; ~

- . . ~ . . . . ~ .
. .
:. . ~ . ~. , .; :
:: : ,- - . .: .
,, , . ~ .. .

'~ 2 Table lc Fluorinated Cationic Surfactants used in Examples 1 to 95 .. . .
R~-Surfactant Name or Formula ~ . .
A32 . C8Fl7S02NHC3H6~(c~3)3~1 A33 CsFl7S02N~IC3H6~(C~3)2~2Hs~ 020C2H5 .
A34 . C8Fl7S02NHC3H6~(CH3) A35 C7FlsCON~C3H6~(CH3)3~i A3~ Cl3Fl7SO2N~c3~l6~(cH3)2c~i2~6Hs~

. A37 ~8FI7s~2N(cH3)c3H6~(cH3)3~

A38 CsFl7S02NHC3H6~(C2H5) C ~ 020C2H5 A39 ~6Fl3~l2cH2scH2cH2~(CH3) A42 F- 15 (JCJ) .... .,.. , . . .. ~, . , , . . ,, . . . ... ,.. .. .. ~ .. ,.. . ... . . .. . ...... .~ . ... ... .
. .

i52 Table ld Fluorinated Non-ionic Surfactants used in Examples R~-Surfactant Name or Formula _ ___ _ _ _ _ .

' ' " " ' . . . ' " ' '` '. :. ' `' ' ' .'~ "" " ' ' ' ' ' ', '', " :
'' ~ ; '' ,.. ' ' ' ' .:
" . . ' ' ' . . ' , ' .. '. ', ' . ' . ., ' Table 2 R~-Synergists used in Examples ~~ . . ~
Syner- Name Formula _ RfCH2CH2SCH2CH2CONH2 . wherein:
.Bl 3-[1,1,2~2-tetrahydroperfluoroal-%C6Fl3 ~C8Fl7 %CloF
kylthio]propionamide 65 23 5 B2 as above 67 10 B3 . as above . . ~0 14 B4 as above . 71 23 2 ~5 as above . 35 36 20 B6 ; as above 100 B7 as above ! oo . . RfCH2CH2SCH2CH2CI~
B8 3-[1,1,2~2-tetrahydroperTluoroal- . wherein:
kylthio]propionitrile 40 42 12 B9 as above 100 B10 as above 100 . ..................... RfCH~CH2SCH2cH(cH~)cONH2 ~11 2-methyl-3-[1,1,2,2~tetrahydropPr- wherein:
fluoroalkylthio]propionamide 40 42 12 Bl~ as above 100 B13 N-[2-(2-methyl-4-oxopentyl)]3-RfCH2CH2SCH2CH2CO~HC(CH3)2CH2COCH3 ~1,1,2,2-tetrahydroDerfluoroal-wherein:
kylthio propionamide~ 40 42 12 B~4 as above 100 B15 N-methylol-3-[1,1,2,2-tetrahydro- . .
perfluoroalkylthio]propionamide 100 B16 perfluorooctanamide 100 (C7Fl5COr~H2) .
. ~. ., ~ ,, Table 2 (Continuation~

Rf-Synergists used in Examples ___ ~
B.- __ .____.
f Name Formula Syner-~ist _ . _ _ _ RfCH2CH2SCH2CH2CONHC(CH3)2CH2C 3 wherein:
B17 nitxlle/ 6 13 ~/C3Fl7 %Clo 21 100 (C7F15CN) B18 N-methyl-per-(C~F17S02~HCH
fluorooctane 100 sulfonamide Bl9 N-methyl, N-(C8F17S02N(CH3)cH2c~l20 ) hydroxyethyl 100 perfluorooctane sulfonamide B20 1,1,2,2-tetrahydro- lOO(RfCH2CH2SCH2CH20COCH3) perfluoxoalkyl-thioethylacetate .B21 2-iodo,1,1,2,3,3-C6F13CH2CHICH2CN
pentahydroper-. fluorononyl nitrile ___ . . _. . __ __ .

,. ; . -... . . .
,, .; , 1 6~

Examples 1 to 17 Fluorinated surfactants of the diverse types as shown in Table 3 were compared at the same dilution in the presence of a typical Rf-synergist B6, with and without added magnesium sulfate. As îs shown without exception~ the observed surface tension is markedly reduced in the presence of Rf-synergist.
With magnesium sulfate alone (no synergist present) the anionic Rf-surfactants show a marked improvement in sur-face tension while the amphoterics, cationics and non-ionics show no appreciable change.
When the Rf-synergist is used on the various sur-factants in conjuction with magnesium sulfate not only are all the observed surface tensions markedly reduced, but the effect on Rf-anionic surfactants is especially pronounced.
The test solutions exhibit varying degrees of clarity and, significantly, many of the solutions are clear. It has been found that the addition of small quan~ities of conven-tional hydrocarbon surfactants to the cloudy compositions will frequently improve their compatibility.

.;.`!

... . ~ . . . . - , . `- ` ` ` , ', ' `. . : :.
:` ` ~ ` ';,` `. ., :

Table 3 ~ Effect of Rf-Synergists on Rf-Surfactants R~-Surfactant ~ Variable ......................................... 1.67%4 R~-Synergist ........................... B6 ............. ...,,,,,.. 0.33V/~
Solvent .......................................................... ,,.,, 25~/o Magnesium Sulfate Heptahydrate ......... ,..... ,.... ,.... ,,.,.,.... ....,0.6 %
_ ____ _ ~x-ample Num- Surface ber Rf-Surfactant Rf-Synergist2~I9SO~-7 H202 TensionlClarityl~3 none ~ _ 35 ~
. ~
F-l - - - 26.0 --anionic ~ - 18 4 a 15.7 a _ 2 F-2 ~- - 20.4 b anionic' + . - 18 8 c ' ~ + 17.1 c _ ._ .
3 F-3 . - 18.5 --" cationic + ~ 15 8 --. ~ 1~.8 . --. . . _ _ _ __ __

4 F-9 - - 26.0 --- " ~ - 22.8 b anionic _ ~ 21.4 a ~ + 20.0 --_ __ , F-13 - - 22.7 c " ~ - 21 ~ cnon-ionic _ ~ 23 5 c ~ * 21.~ c ..
: 6 F-15 - - 28.5 --- 24.2 --- cationic ~ ~7 4 ~ + 22.9 ~.,~

:: : : ' ' .,., , :. ., : .
", ' ' ' . ' ', ' '' ' ' ' ' ""'''' ` :' . , . ~
::: :: ., : : ': . .. ' :

.

:
:
~I,ontin_tion) __ , ... ......... ____ Ex-amp le Num~ . Surfdce ber Rf-Surfactant Rf-Synergist2 ~,gSOI, 7 H2O2 Tensionl Clarityl ~3 ~ . ... _ . ; . ~ ~
none + - _ 35 c~
~ _ _ 7 ~-S - 18.3 ~-" . . f - 17.1 a " anlon1c ~ 17.9 a ~ 16.9 b . . . .. _ ._ . .
8 F-6 - - 19.3 --,, anionic _ + lB B c _ " ~ - 17.~ c 6~ dilution in distilled water; corresponds to 0.1% Rf-sur~actant and 0.02%
Rf-synergist . -`
2Ingredient present (~), absent (~) 3Clarity: -- = clear; a - opalescent; b = sli~ht precipitate; c = precipitate 4Tngredients corrected for dilution as necessary; 100,' actives sFiltered solution for measurement of surface tension ' , . . ~ ~ . .. . -i2 TabLe 3 (Continuat-ion) Ex ample Num- Surface ber Rf-Sur-factant Rf-Synergist MgSO~t 7 H202 Tension C1arityl~3 g F-7 - - 17.8 --16.3 a~photeric _ ~ 17.3 --+ + 16.3 F-9 - - 20.8 . --non-ionic . + - 18 1 b '' - + ~ -18.0 a l~ F-8 . - - 19.9 " + - 15.6 b " cationic . _ ~ 20.0 --~ 15.8 --12 A23b ~~ ~ 19.7 __ + _ 16.7 " amphoteric - + 19.6 --" + + . 16.1 --.
13 A12 - - 24.9 --" + . - 21.6 c " anionic _ + 18.8 --~ + ~6.1 . c : ~ ~; 14] A1 28 9 b ,j anionic _ ~ 21.4 --+ 17.1 --A8 29 46 -~-u anionic ~ 19.7 --~ 15~6 --.

16 ~13 anionic ~ 19 6 __ : l6% dilution in distilled water; corresponds to 0.1% R~- sur-factant and 0.02V/o R~-synergist 3Ingredient present (+), absent ~-) Clarity: -- = clear; a = opalescent; b = slight precipitate;
~-- c = precipitate .. . .. ........ ... . ....
- -..... , .~ .... . . .
i . - , . . ..
. . .: . . . . ~... , . .. :. .... . .. ...
.. . . . - .. . . . ..
, , ; .. ~ - . ... ... . . . . .

.. . . . . . .. .
. , . . : , xamples 17 to 24 Table 4 shows that Rf-synergists of widely diverse types will all effectively clepress the surface tension of a typical Rf-surfactant from its initia} surface tension of 28.9 dynes/cm (see Table 3).
Surface tensions of 15-17 dynes/cm are generally attain-able, a remarkable depression of 11~13 dynes/cm. Even in the absence of magnesium salt, substantial synergists effects are observed. With rare exception, surface tension values as low as 15-16 dynes/cm at such low fluorinated surfactant concen-tration have not previously been reported. In fact, these low synergistic surface tensions approach 14.5-15.0 dynes/cm, which is believed to be the lowest theoretically attainable value for an aqueous fluorosurfactant.

. . . ~

, .

.... . .. . . ... . . . . . . . j, -.

5;2 Table 4 Effect o~ Rf-Synergist Types Anionic Rf-Surfactant .................... A1 ..................... 1.67%
R~-Synergist ............................. Variable Solvent .................................. E4 .. ~................... 25~
Magnesium Sulfate Heptahydrate ................ ................... . 0.5%
Example . ....... Concentrate _ _ Surface Number Rf-Synergist % ~lgS04-7H202 Tension3 Clarity4 _. ........ . .
17 B6 0 33 . ; . 12l 1. b 18 B9 .. 0.33 _ 18 8 b . . . . l.lO ; 18 3 .

19 B12 0.33 ; 21 1 b ~ . l.lO ; 15 8 b B14 0.33 ; 12l 3 l.lO . _ 19.4 b . . ~ 16.8 __ 21 Bl8 0.33 _ 20.1 ~ 16.6 22 Bl9 0.33 + l8 8 23 B17 0.33 ~ 18.2 b ~ l6 2 ~ -, . . ~
.

~,f,~ 6~

IIngredjents corrected for dilutlon as necessary; lOOYo actives 2Ingredient present (~), absent (-) 36% dilu~jon in distilled wate~ corresponds to 0;10% R~-surfactant, and 0.02% Rf-synergist for 0.33~O Rf-syner~ist; 0.067,~ Rf-synergist ~or 1~1% Rf-synergist 4ClaritY: -- = clear; b = slight precipitate Examples 25 to 30 Table 5 shows how in examples 26 and 27 versus 25 and examples 29 and 30 versus 28, compositions with R~-synergist exhibit much lower surface tensions than do the R~-surfactants alone, and certain Rf-sur~actant/R~-synergist mixtures are better than others. The marked improvement in properties is apparent even at 0.01% concentration and a divalent salt is not present.

- . . .
;. ...

Table 5 Surface Tension Versus Concentration Ex-ample 1Sur-fac~ T~nsion (dynes/crn) Num- Solids Composition % Solids ber R~-Sur~actantParts Rf-Synergist Parts 1.0 ¦ .1 .01 .001 .0001 ~ _ _ _ _ ___ __ Al 100 . 27 30 42 57 26 Al .75 Bl 25 16.7 19.8 33.8 51.5 27 A2 82 B2 18 16.3 22.1 32.9 54.3 28 A23a 100 .20 2Q 21 28 61 29 A23b 72 Bl ~5 ~5.1 15.6 27.3 54.2 A23c 82 B2 18 16.0 16.7 34.0 63.5 ,_~ ~ _ _ __ . ' _ .
The compositions contain 45% solids in 20¦80 hexylene glycoltwater Examples 31 to 38 Table 6 shows how the ~MC plots of the subject com-positions are effected by the add;tion of a preferred Rf-synergist. The surface tensions are progessively improved over the entire concentration range as Rf-synergist B6 is addedg both with and without magnesium ions~ present~ Values with magnesium are considerably better and the solutions are apparently more stable. Approximately 10~/o of the synergist is sufficient to attain a minimum surface tension.

. .
...

~ 39 -~ , .
r - . - ` , .

Table 6 Surface Tension Versus Concentration ..... .. .. ....

. Surface Tension Solids Compositionl (dynes/cm) ExampleRf-Surfactant A3 Rf-Synergist B6 ~t~S04 7H20 % Soi;ds2~3 Number parts parts parts .1 .01 .001 _ _ _ . ~ _ 31 100 ~ . _ 2g.2 ~6.6 48.1 32 100 6.6 _ 21.7 20.2 41.7 33 100 . 13.2 _ 18~9b 21.4 42.1 34 100 . ~0.0 -- 19,0b 20.6 40.0 100 . _ 30 - 19.7 20.1 43.9 ; 36 ~ 100 6.6~ 30 17.3 16.5 34.7 3;7 100~ 13.2 30 16.4 16.7 30.8 : ; 3~ ~ 20.0 30 15.~ 15.8 30.0 . . ~
lThe compositions contain approximately 2% solids in 25/75 bu~y~
~ ~ CR~ d~4~ y~ glycolr~o b ~y l~h~r~wQ~r-2Based on Rf-Surfactant A3 . 3Glarity: clear unless denoted b, slight precipitate within 1 day :

~, .
-: . - , ~, - ~. . . . .

.. . . ~ , ~L~L~ 2 Exam ~ 6 , Table 7 shows Examples 39 to 66 can be prepared as compositions which exhibit improved surface properties in the context of this patent.

. rdble 7 Other Effective Fluorinated Synergist/Surfactant Compositions Example . . Exa~ple R~
Number Rf-Surfactant Rf.-Synergist Nu~,ber ~f-Surfactant S~nerg~st _ ~- _ . . ....... _~
39 A4 . B3 53 A26 B20 A5 B4 5 4 A27 B l 41 A6 B5 . 55 A28 Bl 5 42 A7 B7 56 A29 Bl~
: . 43 A9 B8 57 A31 44 Al O BlO 58 A32 el . . Al 1 Bl l 59 A33 Bl 46 Al 9 Bl3 60 A34 B~
47 A20 B6 61 A35 Bl 48 A21 B6 62 A36 Bl 49 A22 Bl 7 63 A37 Bl A24 Bl 9 64 A38 Bl 51 A25 B20 65 A39 Bl _ _ _ _ 66 ~ ~l - ~ . . ~ . , ; .

i 2 Exam~les 67-95 The following tables summarize the results of measure-ments on example systems of indîvidual anionic fluorochemical surfactants (Table 8) and surfactant/synergist systems ~Table 9). Table 10 demonstrates the effect of varying amounts of magnesium.
In preparation for the testing reported in Table 8 solutions of the named surfactants were prepared at 0.1% in distilled water and their surface tensions were measured using the Cenco-Du-Nuoy ring tensionmeter after 5 minutes equilibra-tion. To a fresh aliquot of that solution a stoichiometric amount of magnesium sulfate was added and the surface tension of each solution was again measured. Table 8 shows the depres-sion of the surface tension achieved by using the magnesium salt.

, .

.. . . . . , . .... ~ , . .. ..
.

Table 8 Ex-ample Rf-Sur- Surface Tension (dynes/cm) ber factant As Is With Magnesium Added Change 67 F-l 26.0 21.5 ~5.5 68 F-2 20.4 18.3 ~2.1 69 F-10 26.0 21.4 -5.6 F-5 18.3 17.9 -0.4 71 F-6 19.3 18.8 -0.5 72 A-12 24.9 18.8 -6.~
73 A-l 28.9 21.4 -7.5 74 A-8 29.6 19.7 _9.9 ~-3 28.2 1~ 7 -8.5 Table 9 shows that when magnesium sulfate is employed in a surfactant- synergist combination, the surface tension is further depressed.

''..''' ' '' ,. ~, ~' ' ~, ' . ' ' ~ ' ' '~ ' ' ''' ' '' , ' '

6~i2 Table 9 Ex R -Sur-ample f~ctant/ Ratio Surface Tension (Dynes/cm) Num- Syner-ber gi~t As IS With Magnesîum Added Change 76 F- l/B6 5:118.4 15.7 -2.7 77 F-2/B6 5:118.8 17.1 -1.7 78 F-10 31/B6 5:122.8 20.0 -2.8 79 F-5 SA/B6 5:117.1 16.9 -0.2 F-6/B6 5:117.9 17.9 -0-81 A-12/B6 5:121.6 16.1 5.5 82 A-l/B6 5:121.4 17.1 -4.3 83 A-8/B6 5:123.4 15.6 -7.8 84 A~l/B6 5:121.4 17.3 -4.1 A-l/B9 105:118.3 15.0 -3.3 86 A-l/B12 1.5:123.3 15.8 -7.5 87 A-l/B14 5:121.9 18.3 ~ 3.6 88 A-l/B18 5:120.1 16.6 -3.5 89 A~l/B19 5:119.4 18.8 -0.6 A-l/B21 5:118.5 16.2 -2.3 91 = 5:1 19.0 15.8 -3.2 :
- .: .
. .

.i~ . . .. , . :

z Table 10 shows the relationship between the relative amounts of magnesium salt and surfactant employed and the surface tension depression achieved. The surfactant and the surfactant/synergist concentrations were held constant at 0.01% and the ratio of surfactant to synergist was 6:1.

Table 10 . __ _. _ _ _ Ex- Magnesium Level Surface Tension Depression (dyneslcm) ample Num~ _ _ ber Surfactant Alone Surfactant/
~ ~ SYner~ist (A3/B4 _ __ . _ " . .
92 None -0- -0-93 0.2 Equivalents 8.1 3.8 94 1 Equivalent 9.5 4.0 L~ L 11 LV~ I en 1 10 . 4 ¦ 4 . 8 ?,~. j_ ' ," ' '.. ' " ' ' ., . ~.,. , ' . .' .,. ~.

, '~' " . ,' ' ` ', `

Claims

CLAIMS:

1. A method of improving the surface tension properties of solutions of cationic, anionic, non-ionic, amphoteric or mixed function fluorinated surfactants characterised in that to said surfactant solutions at least one of the component (1) a fluorinated synergist of the formula (Rf)nTmZ
wherein Rf is a straight or branched chain perfluoroalkyl of 1 to 18 carbon atoms or said perfluoroalkyl substituted by perfluoroalkoxy of 2 to 6 carbon atoms, n is an integer of 1 or 2, T is a divalent group -R3- or a group -R3SCH2CHR1-where R3 is straight or branched chain alkylene or halo-alkylene of 1 to 12 carbon atoms, arylene of 6 to 12 carbon atoms, alkylenethioalkylene or alkyleneiminoalkylene of 2 to 12 carbon atoms, where in said imino group the nitrogen atom is secondary or tertiary and R1 is hydrogen or alkyl of 1 to 12 carbon atoms, Z is a neutral or a polar group selected from -CONR1R2, -CN, -CON(R1)COR2, -SO2NR1R2, -R3(O2CR1) and -CO2R1 where R1 and R2 are independently hydrogen, alkyl of 1 to 12 carbon atoms or alkyl substituted with one or more -OH, -COCH3, -SH, -CONH(CH3), and R3 is as defined above, m is an integer from 0 to 2, the fluorinated synergist has solubility in water at 25°C below 0.01% by weight, and component (2) a magnesium salt is added.

2. A method according to claim 1, characterised in that the fluorinated synergist is added to the solution of the fluorinated surfactant.

3. A method according to claim 1, characterised in that the fluorinated surfactant is of the formula (Rf)nAmQ
wherein Rf, n and m are as defined in claim 1, Q is a water solubilizing group which is an anionic, cationic, non-ionic or amphoteric moiety or a combination of such moieties, A is a multivalent linking group, arylene, alkyl sub-stituted phenylene or the group C6H4YC6H4, where Y is alkylene of 1 to 4 carbon atoms, oxygen, sulfur, sulfonamido-alkylene or carbonamidoalkylene.

4. A method according to claim 3, wherein A is alkylene of 1 to 12 carbon atoms or phenylene and Y is methylene.

5. A method according to any one of claims 1 to 3 characterised in that the fluorinated groups in both the synergist and the surfactants are perfluoroalkyl of 5 to 12 carbon atoms.

6. A method according to claim 1 for comprising the sur-face tension properties of anionic fluorinated surfactant solutions, characterised in that to said surfactant solutions a magnesium salt is added.

7. A method according to claim 1 for improving the sur-face tension properties of anionic fluorinated surfactant solutions, characterised in that to said surfactant solutions the fluorinated synergist and the magnesium salt is added.

8. A method according to claim 6 for lowering the surface tension of an aqueous solution of an alkali metal salt of said anionic fluorinated surfactant by adding thereto 0.1 to 5 equivalents per equivalent of the surfactant of a magnesium salt consisting of magnesium sulfate, magnesium nitrate, magnesium chloride and magnesium acetate.

9. A method according to claim 7 for lowering the surface tension of an aqueous solution of an alkali metal salt of said anionic fluorinated surfactant by adding thereto the fluorinated synergist and 0.1 to 5 equivalents per equivalent of the surfactant of a magnesium salt consisting of magnesium sulfate, magnesium nitrate, magnesium chloride and magnesium acetate.

10. A method according to claim 8, characterised in that the magnesium salt is magnesium sulfate.

11. A method according to claim 9, characterised in that the magnesium salt is magnesium sulfate.

12. A method according to claim 8, characterised in that the anionic fluorinated surfactants are carboxylic acids and salts thereof, sulfonic acids and salts thereof, phos-phonates, phosphates, related phosphoro derivatives and salts thereof.

13. A method according to claim 9, characterised in that the anionic fluorinated surfactants are carboxylic acids and salts thereof, sulfonic acids and salts thereof, phos-phonates, phosphates, related phosphoro derivatives and salts thereof.

14. A surfactant composition having improved surface tension properties, characterised in that it contains 6.6 to 67 parts of at least one of component (1) a fluorinated synergist of the formula (Rf)nTmZ

wherein Rf is a straight or branched chain perfluoroalkyl of 1 to 18 carbon atoms or said perfluoroalkyl substituted by perf1uoroalkoxy of 2 to 6 carbon atoms, n is an integer of 1 or 2, T is a divalent group -R3- or a group -R3SCH2CHR1-where R3 is straight or branched chain alkylene or halo-alkylene of 1 to 12 carbon atoms, arylene of 6 to 12 carbon atoms, alkylenethioalkylene or alkyleneiminoalkylene of 2 to 12 carbon atoms where in said imino group the nitrogen atom is secondary or tertiary and R1 is hydrogen or alkyl of 1 to 12 carbon atoms, Z is a neutral or a polar group selected from -CONR1R2, -CN, -CON(R1)COR2, -SO2NR1R2, -R3(O2CR1) and -CO2R1 where R1 and R2 are independently hydrogen, alkyl of 1 to 12 carbon atoms or alkyl substituted with one or more -OH, -COCH3, -SH, -CONH(CH3), and R3 is as defined above, m is an integer from 0 to 2, the fluorinated synergist has solu-bility in water at 25°C below 0.01 % by weight, and (2) up to 36 parts of a magnesium salt as component (2), per 100 parts of a cationic, anionic, non-ionic, amphoteric or mixed-function fluorinated surfactant.

15. A surfactant compositon according to claim 14, charac-terised in that it contains a mixture of said fluorinated surfactants and the fluorinated synergist.

16. A surfactant composition according to claim 14, charac-terized in that the fluorinated sufactant is of the formula (Rf)nAmQ
wherein Rf, n and m are as defined in claim 14, Q is a water solubilizing group which is an anionic, cationic, non-ionic or amphoteric moiety or a combination of such moieties, A is a multivalent linking group,arylene, alkyl sub-stituted phenylene or the group C6H4YC6H4 where Y is alkylene of 1 to 4 carbon atoms, oxygen, sulfur, sulfonamidoalkylene or carbonamidoalkylene.

17. A surfactant composition according to any one of claims 14 to 16, characterised in that the fluorinated groups in both the synergist and the surfactants are perfluoroalkyl of 5 to 12 carbon atoms.

18. A surfactant composition according to claim 14, characterised in that it contains the anionic fluorinated surfactant and a magnesium salt.

19. A surfactant composition according to claim 14, characterised in that it contains the anionic fluorinated surfactant, the fluorinated synergist and the magnesium salt.

20. An aqueous surfactant composition according to claim 18, characterised in that it contains an alkali metal salt of the anionic fluorinated surfactant and 0.1 to 5 equivalents per equivalent of the surfactant of a magnesium salt consisting of magnesium sulfate, magnesium nitrate, magnesium chloride and magnesium acetate.

21. An aqueous surfactant composition according to claim 19, characterised in that it contains an alkali metal salt of the anionic fluorinated surfactant, the fluorinated synergist and 0.1 to 5 equivalents per equivalent of the surfactant of a magnesium salt consisting of magnesium sulfate, magnesium nitrate, magnesium chloride and magnesium acetate.

22. A surfactant composition according to claim 20, characterised in that it contains magnesium sulfate.

23. A surfactant composition according to claim 21, characterised in that it contains magensium sulfate.

24. A surfactant composition according to claim 20, characterised in that the anionic fluorinated surfactants are carboxylic acids and salts thereof, sulfonic acids and salts thereof, phosphonates, phosphates, related phosphoro deri-vatives and salts thereof.

25. A surfactant composition according to claim 21, characterised in that the anionic fluorinated surfactants are carboxylic acids and salts thereof, sulfonic acids and salts thereof, phosphonates, phosphates, related phosphoro derivatives and salts thereof.

26. A liquid concentrate surfactant composition for preparing a surfactant composition according to claim 14 by dilution with water, characterised in that the solids content is from 2 to 45 % by weight and the solvent is a water-hexylene glycol (80/20)- or a water-diethyleneglycol monobutylether (75/25)-mixture.