# Patent

## Title
Fluorosurfactants

## Abstract

The present invention relates to novel compounds containing fluorinated end groups, to the use thereof as surface-active substances, and to processes for the preparation of these compounds.

## Background
The present invention relates to novel compounds containing fluorinated end groups, to the use thereof as surface-active substances, and to processes for the preparation of these compounds.
Fluorosurfactants have an outstanding ability to reduce surface tension, which is utilised, for example, in the hydrophobicisation of surfaces, for example of textiles, paper, glass, building materials or adsorbents. In addition, it is possible to use them as interface promoter or emulsifier or viscosity reducer in paints, surface coatings or adhesives.
In general, fluorosurfactants contain perfluoroalkyl substituents, which are broken down to perfluoroalkylcarboxylic acids (PFCAs) and -sulfonic acids (PFASs) in the environment by biological and/or other oxidation processes. In recent years, the accumulation of perfluoroalkylcarboxylic acids (PFCAs) and perfluoroalkylsulfonic acids (PFASs) in nature has given cause for concern. PFCAs and PFASs are highly persistent compounds whose long-chain variants (containing perfluoroalkyl chains of 8 or more carbon atoms) have a bioaccumulative potential. They are in some cases suspected of causing health problems (G. L. Kennedy, Jr., J. L. Butenhoff, G. W. Olsen, J. C. O'Connor, A. M. Seacat, R. G. Biegel, S. R. Murphy, D. G. Farrar, Critical Review in Toxicology, 2004, 34, 351-384).
Specific applications of sulfotricarballylates containing optionally fluorinated alkyl groups or aryl groups are described in U.S. Pat. No. 4,988,610, U.S. Pat. No. 6,890,608 and in A. R. Pitt et al., Colloids and Surfaces A: Physicochemical and Engineering Aspects, 1996, 114, 321-335; A. R. Pitt, Progr. Colloid Polym. Sci., 1997, 103, 307-317 and Z.-T. Liu et al., Ind. Eng. Chem. Res. 2007, 46, 22-28.
The Omnova company markets polymers whose side chains contain terminal CF3 or C2F5 groups. International Patent Application WO 03/010128 describes perfluoroalkyl-substituted amines, acids, amino acids and thioether acids which contain a C3-20-perfluoroalkyl group.
JP-A-2001/133984 discloses surface-active compounds containing perfluoroalkoxy chains which are suitable for use in antireflection coatings. JP-A-09/111,286 discloses the use of perfluoropolyether surfactants in emulsions. DE 102005000858 A1 describes compounds which carry at least one terminal pentafluorosulfuranyl group or at least one terminal trifluoromethoxy group and contain a polar end group, are surface-active and are suitable as surfactants.
There continues to be a demand for alternative surface-active substances, preferably having a property profile comparable to that of classical fluorosurfactants and equally great chemical versatility, which are preferably not degraded to long-chain persistent fluorocarboxylic or fluorosulfonic acids on oxidative or reductive degradation or are preferably effective as conventional fluorosurfactants in relatively low dosage.
Novel compounds have now been found which are suitable as surface-active substances and preferably do not have one or more of the above-mentioned disadvantages.
The present invention relates firstly to compounds of the formula (I)




where

the groups Zi (Z1, Z2 and Z3) are, independently of one another, branched or unbranched alkyl groups or groups of the structure Ri(A(CR1R2)ci—(CR3R4)c′i))di—, where the respective indices ci and c′i are, independently of one another, 0-10, and di=0-5, where Ri is a branched or unbranched, fluorine-containing alkyl radical, R1 to R4 are, independently of one another, hydrogen or a branched or unbranched alkyl group, ci and c′i are not simultaneously 0, and A=O, S and/or N,

Y1 is an anionic polar group and Y2 is a hydrogen atom, or vice versa,

X is a cation,

and at least one of the groups Zi is a group of the structure Ri(A(CR1R2)ci—(CR3R4)c′i)di—.

It is preferred for formula (I) that a) di>0 if Z1, Z2 and Z3 are all a group of the structure Ri(O(CH2)ci)di and all Ri are selected from CF3CF2CH2—, CF3CF2CH2CH2—, CF3CF2CF2CH2— or H(CF2)4CH2— and/or that b) Y2 is not equal to OSO3− and X is not equal to Na+ or K+ if Z1=Z2=Z3 and all Zi are selected from C4F9CH2CH2—, C6F13CH2CH2— or C8F17CH2CH2—.
The radicals Ri are branched or unbranched, fluorine-containing alkyl groups. The radicals Ri may be partly or perfluorinated and preferably contain terminal perfluorinated groups. Preference is given to branched or unbranched, fluorine-containing alkyl groups having 1 to 10 C atoms. Unbranched fluorine-containing alkyl groups preferably contain 1 to 6 C atoms, in particular 1-4 C atoms. Branched fluorine-containing alkyl groups preferably contain 3 to 6 C atoms, in particular 3-4 C atoms. The branched fluorine-containing alkyl groups used are preferably (CF3)2—CH— or (CF3)3—C— groups.
R1 to R4 are preferably, independently of one another, hydrogen or a C1-4-alkyl group, in particular H or CH3. ci and c′i are preferably, independently of one another, an integer from the range 0 to 6, in particular 0-3, particularly preferably 0-2, where ci and c′i are not simultaneously 0. di is preferably an integer from the range 0 to 3, particularly preferably 1-3, in particular 1.
A is preferably equal to O or S, in particular O. In particular, the groups Zi are equal to Ri(O(CR1R2)ci(CR3R4)c′i)di—.
Particular preference is given to compounds where R1 to R3 are equal to hydrogen, R4 is equal to hydrogen or methyl, ci and c′i are, independently of one another, equal to 0-2, in particular 1, di is equal to 0-3, in particular 1-3, and A is equal to 0, where ci and c′i are not simultaneously 0. In a preferred variant of the invention, R4 here is equal to methyl and the variables have these preferred meanings. Also suitable are compounds in which R1 is equal to methyl and R2 to R4 are equal to hydrogen, where the variables have the preferred meanings.
Particular preference is given to compounds of the formula (I) in which the fluorine-containing groups Zi are equal to Ri(O(CH2)ci)di—, where the respective indices ci=2-10, preferably 2-4, in particular 2, and di=0-5, preferably 0-3, particularly preferably 1-3, in particular 1, Y1 is an anionic polar group, and Y2 is a hydrogen atom, or vice versa, X is a cation, and at least one of the groups Zi is a group of the structure Ri(O(CH2)ci)di—, where preferably a) d>0 if Z1, Z2 and Z3 are all a group of the structure Ri(O(CH2)ci)di— and all Ri are selected from CF3CF2CH2—, CF3CF2CH2CH2—, CF3CF2CF2CH2— or H(CF2)4CH2—, and b) Y2 is not equal to OSO3− and X is not equal to Na+ or K+ if Z1=Z2=Z3 and all Zi are selected from C4F9CH2CH2—, C6F13CH2CH2— or C8F17CH2CH2—.
Preference is furthermore given to compounds of the formula (I) in which Z1, Z2 and Z3 are, independently of one another, F3C(CF2)ai(CH2)bi—(O(CH2)ci)di— groups, where ai=0-6, preferably 1-5, in particular 1-2, bi=1-6, preferably 1-3, in particular 1-2, ci=2-10, preferably 2-4, in particular 2, and di=0-5, preferably 1-3, in particular 1, where, in particular, Z1=Z2=Z3. Preference is also given to compounds in which ai=0, 1 or 2, preferably 1 to 2, in particular 1, bi=1, ci=2, and di=1 or 2, in particular 1, and where a1+a2+a3>1.
If all Z1, Z2 and Z3 are selected from CF3CF2CH2—, CF3CF2CH2CH2—, CF3CF2CF2CH2— or H(CF2)4CH2—, di in formula (I) is preferably greater than 0. If Z1=Z2=Z3 and all Zi are selected from C4F9CH2CH2—, C6F13CH2CH2— or C8F17CH2CH2—, Y2 is not equal to OSO3−, and X is not equal to Na+ or K+.
In an embodiment of the invention, the compounds according to the invention can be in the form of mixtures, in which the individual compounds have different values for ci, c′i and/or di.
The compounds of the formula (I) according to the invention may contain one or more fluorinated groups Zi according to the invention. The compounds preferably contain two or three fluorinated groups Zi, particular preference being given to those containing three fluorinated groups Zi.
The three substituents Z1, Z2 and Z3 may all be identical, may all be different or two of them may be identical and one of them different, with the proviso that Z1, Z2 and Z3 are not all simultaneously unfluorinated, branched or unbranched alkyl radicals. Preferred compounds are those in which two of Z1, Z2 and Z3 or all of Z1, Z2 and Z3 are identical, in particular equal to the preferred Ri(O(CR1R2)ci(CR3R4)ci)di— groups described. Very particular preference is given here to the following fluorine-containing alkyl radicals: CF3CH2—, CF3CF2CH2—, CF3CF2CF2CH2—, CF3CF2CH2CH2—, CF3CF2CH2CH2CH2—, CF3CFHCF2CH2—, (CF3)2CH—, (CF3)3C—, CF3(CF2)3—CH2CH2—, CF3(CF2)5CH2CH2—, CF3(CF2)4CH2—. The compounds preferably include fluorine-containing alkyl radicals having at most 3 fluorine-carrying carbon atoms. Particularly preferred compounds of the formula (I) where Z1=Z2=Z3 are those in which ci or c′i is equal to 0 to 3, in particular 0-2, and di>0, where ci and c′i are not simultaneously 0. Compounds according to the invention where di is equal to 1 to 3, in particular 1, are especially preferred.
If the compounds contain unfluorinated end groups Z1, Z2 and Z3, these are preferably, independently of one another, linear or branched alkyl having 1 to 20 C atoms, preferably 1 to 10 C atoms. In particular, Z1, Z2 and Z3 are, independently of one another, linear alkyl having 3 to 10 C atoms, particularly preferably having 3 to 8 C atoms. If two of the groups Z1, Z2 and Z3 are unfluorinated, these two groups are preferably identical.
In a preferred group of compounds to be employed in accordance with the invention or compounds according to the invention, Y1 and Y2, where one of the two is equal to a hydrogen atom, stand for an anionic polar group selected from —COO3−, —SO3−, —OSO3−, —OPO32−, —(OCH2CH2)s—O—(CH2)tCOO−, —(OCH2CH2)s—O—(CH2)tSO3−, —(OCH2CH2)s—O—(CH2)tOSO3−, —(OCH2CH2)s—O—(CH2)t—PO32−—, —(OCH2CH2)s—O—(CH2)t—OPO32− or for the formulae A to C,




where s stands for an integer from the range 1 to 1000, t stands for an integer selected from 1, 2, 3 or 4, and w stands for an integer selected from 1, 2 or 3.

The preferred anionic groups here include, in particular, —COO−, —SO3−, —OSO3−, —PO32−, —OPO32−, the sub-formula A, and —(OCH2CH2)s—O—(CH2)t—COO−, —(OCH2CH2)s—O—(CH2)t—SO3− and —(OCH2CH2)s—O—(CH2)t—OSO3−, where each individual one of these groups taken alone may be preferred.
The very particularly preferred anionic groups here include —SO3−, —OSO3−, —PO32− or OPO32−, in particular —SO3−. Particular preference is given to compounds in which Y1 is a sulfonate group —SO3−, and Y2 is a hydrogen atom.
X is preferably a monovalent cation, in particular H+, an alkali metal cation or NR4+, where R=H+ or C1-C6-alkyl, and all R may be identical or different. X is particularly preferably Na+, K+ or NH4+, especially preferably Na+.
Preferred compounds of the formula (I) are, in particular, compounds in which all variables have the preferred meanings. Preference is explicitly given to compounds in which Z1=Z2=Z3=F3C(CF2)ai(CH2)bi(O(CH2)ci)di—, where ai=1-2, bi=1-2, ci=2, di=1-3, Y1 or Y2 is a sulfonate group —SO3−, and X=Na+.
Particular preference is given to compounds of the formula (Ia) or (Ib):




where Z1=Z2=Z3 and all Zi are selected from Ri(O(CH2)ci)di—, where ci=2, di=1-3, and Ri=CF3CF2CH2— or CF3CF2CF2CH2—.

The compounds of the formula (I) according to the invention are referred to in the present invention as sulfotricarballylates and are based on esters of aconitic acid, onto the double bond of which a sulfonate group has been added. In particular, sulfotricarballylates containing three fluorinated end groups according to the invention are preferred. The compounds of the formula (I) according to the invention can also be in the form of mixtures, particularly also in the form of isomer mixtures (constitutional and/or configurational isomer mixtures). In particular, diastereomer and/or enantiomer mixtures are possible.
Examples of preferred compounds according to the invention are:







where compounds of the formulae Ia-1 and Ia-2 are particularly preferred.

Advantages of the compounds according to the invention may be, in particular:

    
    
        a surface activity which is equal or superior to that of conventional hydrocarbon surfactants with respect to efficiency and/or effectiveness,
        biological and/or abiotic degradability of the substances without the formation of persistent perfluorinated degradation products, such as PFOA (perfluorooctanoic acid) or PFOS (perfluorooctanesulfonate),
        weak foaming action and/or low foam stabilisation,
        good processability in formulations and/or
        storage stability.
    
    


The compounds according to the invention preferably have particular surface activity. The compounds of the formula (I) according to the invention may have significantly improved environmental properties compared with the prior-art fluorosurfactants since they do not undergo either chemical or biological degradation to long-chain PFCAs or PFASs.
The present invention relates secondly to the use of the compounds according to the invention, in particular the preferred compounds of the formula (I), as surface-active agents, for example for improving the flow behaviour and wetting ability of coating formulations.
The preferred embodiments of the compounds according to the invention described above can particularly advantageously be used here. Sulfotricarballylates which contain two or three, in particular three, fluorinated groups according to the invention are preferably used. Compounds of the formulae (Ia) and/or (Ib) are preferably used. The compounds according to the invention can also be used in the form of mixtures, particularly also in the form of isomer mixtures (constitutional and/or configurational isomer mixtures). In particular, diastereomer and/or enantiomer mixtures are possible.
Areas of application are, for example, the use of the compounds according to the invention as additives in surface-coating preparations, such as paints, coatings, protective coatings, speciality coatings in electronic or semiconductor applications (for example photoresists, top antireflective coatings, bottom antireflective coatings) or in optical applications (for example photographic coatings, coatings of optical elements), in polishes and waxes (in particular for furniture, floors and automobiles), or in additive preparations for addition to corresponding preparations.
For use, the compounds according to the invention are usually incorporated into correspondingly designed preparations. The present invention likewise relates to corresponding compositions comprising at least one compound according to the invention. Such compositions preferably comprise a vehicle which is suitable for the particular application and optionally further active substances and/or optionally assistants. Preferred compositions here are paint and surface-coating preparations and printing inks.
In particular, the present invention also relates to water-based surface-coating formulations which comprise at least one of the compounds according to the invention, alone or mixed with other surfactants. Preference is given to the use of surface-coating formulations based on the following synthetic film formers:

    
    
        polycondensation resins, such as alkyd resins, saturated/unsaturated polyesters,
        polyamides/imides, silicone resins; phenolic resins; urea resins and melamine resins,
        polyaddition resins, such as polyurethanes and epoxy resins,
        polymerisation resins, such as polyolefins, polyvinyl compounds and polyacrylates.
    
    


In addition, the compounds according to the invention are also suitable for use in surface coatings based on natural products and modified natural products. Preference is given to surface coatings based on oils, polysaccharides, such as starch and cellulose, and also based on natural resins, such as cyclic oligoterpenes, polyterpenes and/or shellac. The compounds according to the invention can be used both in physically hardening (thermoplastics) and in crosslinking (elastomers and thermosets) aqueous surface-coating systems. The compounds according to the invention preferably improve the flow and wetting properties of the surface-coating systems.
A further area of application of the compounds according to the invention is in processes for the preparation of polymers, in particular fluoropolymers. Important industrial methods for the preparation of fluoropolymers, such as, for example, polytetrafluoroethylene (PTFE), are, for example, emulsion and suspension polymerisation. Suspension and emulsion polymerisation processes are standard polymerisation processes which are well known to the person skilled in the art. In suspension and emulsion polymerisation processes, the system always comprises at least four constituents: (predominantly) water-insoluble monomer, water, dispersant or emulsifier and initiator. The performance of the said polymerisation processes is familiar to the person skilled in the art. In these processes, the polymer is prepared in an autoclave which contains water, the corresponding, usually gaseous, monomer(s), initiator(s), surfactant(s) and other assistant(s), with stirring and constant temperature and pressure control. The compounds according to the invention are suitable as surfactants for keeping the very hydrophobic fluoropolymer droplets or particles dispersed in the aqueous solution.
In addition, the compounds according to the invention can be employed in hydrophobicising agents, oleophobicising agents, wetting/flow-control agents, spot and soiling protectors/cleaning agents, stain releases, antifogging agents, lubricants, antifoams, deaerators, drying accelerators, abrasion resistance and mechanical wear enhancers, and antistatics, in particular in the treatment of textiles (in particular clothing, carpets and carpeting, upholstery in furniture and automobiles) and hard surfaces (in particular kitchen surfaces, sanitaryware, tiles, glass), non-woven textile materials, leatherware, papers and cardboard, wood and wood-based materials, mineral substrates, such as stone, cement, concrete, plaster, ceramics (glazed and unglazed tiles, stoneware, porcelain) and glasses, and for plastics and metallic substrates. For metallic substrates, the claims additionally also relate to the use in anticorrosion agents. For plastics and moulds for plastics processing, the claims additionally also relate to the use in mould-release agents. In the case of cleaning agents and spot removers, the claims additionally also relate to the use as detergent or soiling emulsifier and dispersant.
The compounds according to the invention can furthermore be used as antimicrobial active substance, in particular as reagent for antimicrobial surface modification.
A further area of application of the compounds according to the invention is in additives or in additive preparations in printing inks, having one or more of the following functions: antifoam, deaerator, friction-control agent, wetting agent, flow-control agent, pigment compatibility enhancer, print resolution enhancer, drying accelerator.
The compounds according to the invention can also be used as foam stabilisers and/or for supporting film formation, in particular in aqueous film-forming fire-extinguishing foams, both synthetic and protein-based, also for alcohol-resistant formulations (AFFF and AFFF-AR, FP, FFFP and FFFP-AR).
The compounds according to the invention can furthermore be employed as additives in polymeric materials (plastics), having one or more of the following functions: lubricant, internal friction reducer, UV stabiliser, hydrophobicising agent, oleophobicising agent, spot and soiling protector, coupling agent for fillers, flameproofing agent, migration inhibitor (in particular against migration of plasticisers), antifogging agent.
In addition, the compounds according to the invention are also suitable for use as additives in liquid media for cleaning, etching, reactive modification and/or substance deposition on metal surfaces (in particular also electrocoating and anodisation) or semiconductor surfaces (in particular for semiconductor photolithography: developer, stripper, edge bead remover, etching agent and cleaning agent), as wetting agent and/or deposited film quality enhancer.
In addition, the compounds which can be used in accordance with the invention as surfactant are suitable for washing and cleaning applications, and for use as additives/surfactants in cosmetic products, such as, for example, hair and body care products (for example shampoos, hair rinses and hair conditioners), foam baths, creams or lotions, having one or more of the following functions: emulsifier, wetting agent, foaming agent, lubricant, antistatic, skin grease resistance enhancer.
The compounds according to the invention are furthermore used as additives in herbicides, pesticides and fungicides, having one or more of the following functions: substrate wetting agent, adjuvant, foam inhibitor, dispersant, emulsion stabiliser. In addition, the compounds according to the invention can also be used as additives in de-icing agents or anti-icing agents.
In addition, the compounds according to the invention are suitable as additives in preparations for ore processing, in particular flotation and leaching solutions, having one or more of the following functions: wetting agent, foaming agent, foam inhibitor, and as additives in agents for the stimulation of oil wells, having one or more of the following functions: wetting agent, foaming agent, emulsifier.
A further area of application of the compounds according to the invention is in the use as additives in adhesives, having one or more of the following functions: wetting agent, penetrant, substrate adhesion enhancer, antifoam.
The compounds according to the invention can furthermore be employed as additives in greases and hydraulic fluids, having one or more of the following functions: wetting agent, corrosion inhibitor. In the case of greases, the claims additionally also relate to the use as dispersant (in particular for fluoropolymer particles).
The compounds according to the invention can also be used as additives in putties and filling compositions, having one or more of the following functions: hydrophobicising agent, oleophobicising agent, soiling protector, weathering resistance enhancer, UV stabiliser, agent against silicone bleeding.
The present invention relates to all uses mentioned here of compounds to be employed in accordance with the invention. The respective use of surfactants for the said purposes is known to the person skilled in the art, and consequently use of the compounds to be employed in accordance with the invention will present no problems. The compounds of the formula (I) according to the invention are preferably used in paint and coating preparations, printing inks and waxes, as well as polishes. Particular preference is given to the use in paint and coating preparations.
The use of compounds of the formula (I), in particular the compounds of the formula (I) described as preferred above, in paint and coating preparations is particularly advantageous. Compounds in which the groups Zi are equal to Ri(O(CH2)ci)di—, where the respective indices ci=2-10, preferably 2-4, in particular 2, and di=0-5, preferably 1-3, in particular 1, are preferred here. Compounds of the formula (I) in which Z1=Z2=Z3=F3C(CF2)ai—(CH2)bi(O(CH2)ci)di—, where ai=0-6, preferably 1-5, in particular 1-2, bi=1-6, preferably 1-3, in particular 1-2, ci=2, di=1-3, preferably 1, Y1 or Y2 is equal to a sulfonate group —SO3−, and X=Na+, are particularly preferred. In particular, compounds of the formulae Ia-1 to Ia-6 are suitable for use in paint and coating preparations, particularly those of the formulae Ia-1 and Ia-2.
The compounds of the formula (I) according to the invention can preferably be prepared by esterification of aconitic acid or the anhydride or acid chloride or of citric acid using one or more alcohols ZiOH (II) followed by an addition reaction, preferably of sodium hydrogensulfite.
Zi is an unfluorinated, branched or unbranched, alkyl group or a group of the structure Ri(A(CR1R2)ci(CR3R4)ci)di—, where the respective indices ci and c′i are, independently of one another, 0-10, and di=0-5, where Ri is a branched or unbranched, fluorine-containing alkyl radical, R1 to R4 are, independently of one another, hydrogen or a branched or unbranched alkyl group, ci and c′i are not simultaneously 0, and A=O, S and/or N. Zi preferably encompasses the variables described for the preferred compounds of the formula (I), in particular an F3C(CF2)ai(CH2)bi(O(CH2)ci)di— group, where ai=0-6, bi=1-6, ci=2-10, and di=0-5. ai is preferably equal to 1 or 2, bi is preferably equal to 1 to 3, in particular 1 to 2. ci is preferably equal to 2 to 4, in particular 2. di is preferably equal to 1 to 3, in particular 1.
Preference is given to the use of alcohols containing F3C(CF2)ai(CH2)bi—(O(CH2)ci)di— groups, where one or also various alcohols can be reacted as a mixture or in steps. Preferably, only one alcohol is used, in particular.
The esterification can also be carried out in a mixture with unfluorinated, branched or unbranched alcohols or in steps using various alcohols. The unfluorinated, branched or unbranched alcohols are preferably those containing linear or branched alkyl having 1 to 20 C atoms, preferably 1 to 10 C atoms. Particular preference is given to alcohols having 3 to 10 C atoms, particularly preferably having 3 to 8 C atoms.
The present invention thus relates thirdly to a process for the preparation of compounds of the formula (I), in particular sulfotricarballylates, which contain two or three end groups which are fluorinated in accordance with the invention.
The alcohols used are commercially available and/or their preparation is familiar to the person skilled in the art (Heilmann et al. J. Fluorine Chem. 1992, 59, 387; Janulis et al. U.S. Pat. No. 5,157,159 (1992)).
The aconitic esters are preferably synthesised in the presence of a conventional catalyst, such as, for example, toluene-4-sulfonic acid monohydrate:




The aconitic esters can furthermore preferably be synthesised starting from citric acid in the presence of a conventional catalyst, such as, for example, sulfuric acid. It is also possible to prepare the corresponding citric acid esters (IV).




In a second step, the group Y is then introduced by an addition reaction onto the double bond of the aconitic esters or derivatisation of the OH group of the citric acid esters by methods familiar to the person skilled in the art. The following scheme shows by way of example the synthesis of the sulfotricarballylates by the addition reaction of sodium hydrogensulfite, which can be carried out under conditions known to the person skilled in the art:




The formula (III) reproduces the presence of Z/E double-bond isomers. Further compounds according to the invention can be prepared analogously to the illustrative reactions shown above. Further compounds according to the invention can also be prepared by other methods known from the literature and known per se to the person skilled in the art. In particular, other esterification catalysts can be used.
The present invention relates fourthly to compounds of the formula (III), which occur as intermediates in the above-described syntheses of the compounds of the formula (I) according to the invention:




where

the groups Zi (Z1, Z2 and Z3) are, independently of one another, branched or unbranched alkyl groups or groups of the structure Ri(A(CR1R2)ci—(CR3R4)c′i)di—, where the respective indices ci and c′i are, independently of one another, 0-10, preferably 0-6, in particular 0-2, and di=0-5, where Ri is a branched or unbranched, fluorine-containing alkyl radical, R1 to R4 are, independently of one another, hydrogen or a branched or unbranched alkyl group, ci and c′i are preferably not simultaneously 0, A=O, S and/or N, and at least one of the groups Zi is a group of the structure Ri(A(CR1R2)ci(CR3R4)c′i)di—.

Preferred compounds of the formula (III) are those in which Z1, Z2 and Z3 are, independently of one another, F3C(CF2)ai(CH2)bi(O(CH2)ci)di— groups, where ai=0-6, in particular ai=1-5, preferably 1-2, bi=1-6, preferably 1-3, in particular bi=1-2, ci=2-10, in particular ci=2, and di=0-5, in particular di=1. Particularly suitable compounds are those where Z1=Z2=Z3.
Preference is also given to compounds in which ai=0, 1 or 2, preferably 1 or 2, in particular 1, bi=1, ci=2, and di=1 or 2, in particular 1, and where a1+a2+a3>1.
The present invention relates fifthly to the use of the compounds of the formula (III) as monomers or comonomers in the synthesis of fluorinated polymers.
The disclosures in the cited references are hereby expressly also part of the disclosure content of the present application. The following examples explain the present invention in greater detail without restricting the scope of protection.


EXAMPLES
Example 1
Synthesis of the sulfotricarballylate of the Formula (Ia-1)
a) Esterification




The alcohol used is prepared as described in the literature (Heilmann et al. J. Fluorine Chem. 1992, 59, 387; Janulis et al. U.S. Pat. No. 5,157,159 (1992)). A mixture of 72.4 mmol of alcohol, 18.1 mmol of aconitic acid (90%, Alfa Aesar) and 3.6 mmol of toluene-4-sulfonic acid monohydrate (Merck KGaA) in 40 ml of toluene is subsequently stirred under reflux for 48 hours. The water liberated during the reaction is removed with the aid of a water separator. The reaction is quenched using water. The mixture is subsequently extracted with toluene, and the combined organic phases are washed with water, dried over sodium sulfate and filtered. The solvent is distilled off in a rotary evaporator.
Purification: column chromatography over silica gel;
Eluent: toluene/ethyl acetate 1/2
Substance: C21H21F15O9, M=702.362 g/mol
1H-NMR (400 MHz; in DMSO-d6):
6.84 (s); 4.38-4.09 (m); 3.92-3.74 (m) ppm.
19F-NMR (376 MHz; in DMSO-d6):
−82.85-−83.02 (m); −122.79-−122.94 (m) ppm.
MS (EI, 70 eV) m/e:
553 (10%); 509 (10%); 221 (15%); 177 (100%).
b) Addition Reaction




68 ml of sodium hydrogensulfite solution (39% in water, Merck KGaA) (338 mmol) are added dropwise at 50° C. to a solution of 13.5 mmol of the triester in 45 ml of 1,4-dioxane (Merck KGaA), and the mixture is stirred under reflux. After the dropwise addition, the reaction temperature is held at 88° C. for 65 hours. After 24 hours and 48 hours, 23 ml of sodium hydrogensulfite solution (39% in water, Merck KGaA) (113 mmol) are again added dropwise each time. The solvent is removed in a rotary evaporator. The crude product is subsequently taken up in diethyl ether (Merck KGaA), stirred and filtered. The filter residue is again washed by stirring and filtered. The diethyl ether phases are combined, and the organic solvent is removed in a rotary evaporator.
Substance: C21H22F15O12SNa; M=806.424 g/mol
1H-NMR (400 MHz; in DMSO-d6):
4.31-4.06 (m); 4.00 (d); 3.95 (d); 3.88-3.71 (m); 3.68-3.54 (m); 3.48-3.37 (m); 3.36-3.00 (m); 2.92 (d); 2.87 (d) ppm.
19F-NMR (376 MHz; in DMSO-d6):
−83.23-−83.40 (m); −123.16-−123.55 (m) ppm.
MS (FIA-ESI) m/e:
Pos. mode: 807 (M+H)+
Neg. mode: 783 (M−Na)−
Example 2
Determination of the Static Surface Tension
The static surface tensions γ of aqueous surfactant solutions having various concentrations c (percent by weight) are determined.
Instrument: Sinterface tensiometer (model PAT1)
Temperature of the measurement solutions: room temperature
Measurement method employed: measurement of the surface tension on hanging droplets against air. The principal radii of curvature (r1 and r2) of the ellipsoids (droplets) are determined here by droplet contour analysis. Since the pressure difference (Δp) between the outside and inside of an interface is indirectly proportional to the radii of curvature, the surface tension can be calculated from the following correlation:




  
    Δ
    ⁢
    
      
    
    ⁢
    p
  
  =
  
    γ
    ⁡
    
      (
      
        
          1
          
            r
            1
          
        
        +
        
          1
          
            r
            2
          
        
      
      )
    
  




Instrument settings: droplet volumes 7-10 mm3; measurement time 1500-3600 s; 1.5 pictures/s, droplet density=1 g/cm3.
The measurement values are shown in Table 1. FIG. 1 shows the static surface tension as a function of the concentration of the sulfocarballylate according to Example 1b).










TABLE 1







c [%]
γ[mN/m]



















0.001
49.4



0.013
35.6



0.127
28.5



0.240
24.7



0.308
22.9



0.370
22.6



0.414
22.3



0.451
21.9



0.485
21.2



0.513
20.9



0.610
21.2



1.265
20.7










Example 3
Determination of the Dynamic Surface Tension
The dynamic surface tension γ of a 0.1% (percent by weight) aqueous solution of compound 1b) is determined.
Measurement method employed: measurement of the surface tension using the bubble pressure method
Instrument: SITA tensiometer (model t 60)
Temperature of the measurement solutions: 21° C.±0.2° C.
In the measurement of the dynamic surface tension, air bubbles are forced through a capillary into the surfactant solution at different rates. From the resultant pressure change, the surface tension can be determined as a function of the bubble life using the following equation:




  γ
  =
  
    
      r
      ⁡
      
        (
        
          
            p
            max
          
          -
          
            ρ
            ·
            g
            ·
            h
          
        
        )
      
    
    2
  




pmax=maximum pressure, ρ=density of the liquid, h=immersion depth, r=radius of the capillary

The measurement values are shown in Table 2. FIG. 2 shows the dynamic surface tension as a function of the bubble life for compound 1b).










TABLE 2







Bubble life [ms]
γ[mN/m]



















30
56.1



38
51.5



50
47.7



65
44.1



82
41.9



113
40



141
38.8



189
37.9



243
37.2



306
36.3



414
35.7



533
35.6



674
35.2



924
34.6



1299
34.2



1727
33.9



2200
33.7



2507
33.5



3204
33.5



4102
32.9



5473
32.9



7012
32.7



9132
32.5



11537
32.3



15707
32.1



19795
31.8



26529
31.5



35138
31.4



44790
31.3



58574
31










Example 4
Antipitting Test in a Polyurethane Water-Borne Surface Coating
A surface coating is prepared from the raw materials according to Table 3 in which surface defects (pits) are generated specifically by overdosing the antifoam BYK 023. A highly concentrated solution (95% by weight) of the sulfotricarballylate according to Example 1b in Dowanol PM (Dow Chemicals) is incorporated into the surface coating in various amounts and compared in efficacy to the 0 sample (without sulfotricarballylate).







TABLE 3







Raw materials for surface-coating formulation











Product
Function
Manufacturer







Bayhydrol XP
Binder
Bayer



2470



Bayhydur 304
PUR curing
Bayer




agent



Methoxybutyl
Solvent
VWR



acetate



BYK-023
Antifoam
BYK Chemie



Blue pigment
Contrast to sub-
BASF



paste
strate










In the preparation of the contaminated surface-coating sample, firstly binder, pigment paste and water are initially introduced (Table 4a; PE beaker: 860 ml), and some of the initially introduced mixture is subsequently completed (Table 4b; PE beaker 350 ml).








TABLE 4a







Initially introduced components 1













Formulation
Dissolver/stirrer


Pos.
Raw material
[g]
disc setting













1
Bayhydrol XP 2470
271.18
400 rpm;


2
Pigment paste
8
10 min; 80 mm


3
H2O
27.28

















TABLE 4b







Completion













Formulation
Dissolver/stirrer


Pos.
Raw material
[g]
disc setting













4
Initially introduced
128.55
400 rpm;



mixture

10 min; 80 mm


5
Bayhydur 304
41.03


6
Methoxybutyl ace-
10.27



tate


7
H2O
19.62


8
BYK 023
0.14
600 rpm;





10 min; 60 mm









For incorporation of the surfactant solution, the latter is firstly initially introduced (PE beaker, 175 ml), and the amount of surface coating is subsequently based on the weight of surfactant. Three test coatings having a different surfactant content or without surfactant are prepared (Table 5).








TABLE 5







Incorporation of the surfactant solution












Surface-
Weight of
Weight of
C* sur-
Dissolver/


coating
surfactant
surface
factant
stirrer disc


sample
solution [g]
coating [g]
[%]
setting





1
—
—
0 sample
—


2
0.0544
37.42
0.06
900 rpm;






5 min; 40 mm


3
0.2064
47.39
0.19
900 rpm;






5 min; 40 mm





*Surfactant content based on the total amount of surface-coating sample






The surface coatings are applied to white paint cards (219×286 mm; manufacturer: Leneta) with the aid of an automatic film applicator with vacuum suction (Byk Gardner E-2101) with a film applicator frame (Erichson model 360; capacity: 4 ml of surface coating; metering: 20 ml spraying; drawing speed: 50 mm/s; wet layer thickness: 30 μm).
Surface-coating sample 2 is virtually free of surface defects (pits) and surface-coating sample 3 is completely free of surface defects (pits), whereas surface-coating sample 1 exhibits numerous surface defects (pits).
FIGS. 1 and 2 show the static and dynamic surface tension respectively for compound 1b).
Example 5
Synthesis of the sulfotricarballylate of the Formula (Ia-2)
The sulfotricarballylate of the formula (Ia-2) is prepared by the process described in Example 1.
Empirical formula: C24H22F21O12SNa, M=956.447 g/mol
1H-NMR (300 MHz; in DMSO-d6):
4.26-4.02 (m); 3.91 (dd); 3.82-3.67 (m); 3.63-3.46 (m); 3.44-3.30 (m); 3.25-2.98 (m);
2.89-2.77 (m) ppm.
19F-NMR (282 MHz; in DMSO-d6):
−80.42 to −80.82 (m); −127.11 to −127.50 (m); −119.79 to −120.88 (m) ppm.
MS (FIA-ESI) m/e:
Neg. mode: 933 (M−Na)−
Both the static surface tension as described in Example 2 and the dynamic surface tension as described in Example 3 are subsequently determined. The results are shown in Tables 6 and 7.










TABLE 6







c [%]
γ[mN/m]



















0.0001
54.2



0.0011
30.6



0.0018
27.8



0.0055
25.8



0.011
21.5



0.016
18.4



0.038
17.8



0.045
17.8



0.050
17.8



0.024
17.8



0.100
17.6



0.994
17.6




















TABLE 7







Bubble life [ms]
γ[mN/m]



















31
68



38
66.3



49
62.7



65
58.4



83
52.1



108
44.7



144
34.8



191
27.7



241
25



325
22.9



406
20.4



522
19.3



697
18.9



859
18.8



1163
18.3



1811
18.1



2250
17.8



2590
17.8



3223
17.6



4028
17.4



5615
17.6



7247
17.5



8998
17.4



12741
17.2



16566
17.5



19736
17.1



27035
17.3



34338
16.9



43556
16.8



56679
16.8










Example 6
Synthesis of the sulfotricarballylate of the Formula (Ia-3)
The sulfotricarballylate of the formula (Ia-3) is prepared by the process described in Example 1.
Empirical formula: C21H19F18O12SNa, M=860.395 g/mol
1H-NMR (400 MHz; in DMSO-d6):
5.48-5.37 (m); 5.35-5.21 (m); 4.30-4.09 (m); 4.07-3.90 (m); 3.57-3.46 (m); 3.40-3.32 (m); 3.15-3.05 (m); 2.82 (dd) ppm.
19F-NMR (376 MHz; in DMSO-d6):
−73.53 to −73.85 (m) ppm.
MS (LC-ESI-MS negative):
RT: 9.05 (837 [M−H]−)
Both the static surface tension as described in Example 2 and the dynamic surface tension as described in Example 3 are subsequently determined. The results are shown in Tables 8 and 9.










TABLE 8







c [%]
γ[mN/m]



















0.0001
57.9



0.001
52.5



0.01
44.0



0.10
29.2



0.25
25.4



0.53
22.7



1.03
21.7



1.22
21.3



2.46
21.0



4.74
20.8




















TABLE 9







Bubble life [ms]
γ[mN/m]



















57
31



53.1
38



47.8
52



44.7
64



42
85



39.8
111



38.7
144



37.4
190



36.5
243



36
324



35.5
423



35.2
512



34.9
706



34.6
938



34.4
1209



34
1773



33.8
2145



33.7
2498



33.6
3277



33.5
4172



33.2
5331



33.1
7431



33.1
9743



33.4
11981



32.7
15946



32.2
20560



32.1
27476



32.1
35812



32
47092



31.9
60416










Example 7
Synthesis of the sulfotricarballylate of the Formula (Ia-4)
The sulfotricarballylate of the formula (Ia-4) is prepared by the process described in Example 1.
Empirical formula: C24H16F27O9SNa, M=1016.391 g/mol
1H-NMR (400 MHz; in DMSO-d6):
4.51-4.25 (m); 4.14 (d); 4.08 (d); 3.70-3.59 (m); 3.55-3.45 (m); 3.37-3.15 (m); 2.97 (dd) ppm.
19F-NMR (376 MHz; in DMSO-d6):
−80.95 to −81.39 (m); −113.39 to −114.00 (m); −124.36 to −124.82 (m);
−126.02 to −126.38 (m) ppm.
MS (LC-ESI-MS negative):
RT: 10.60 (993 [M−H]−)
Both the static surface tension as described in Example 2 and the dynamic surface tension as described in Example 3 are subsequently determined. The results are shown in Tables 10 and 11.










TABLE 10







c [%]
γ[mN/m]



















0.0001
71.6



0.0003
66.3



0.0006
40.8



0.0010
22.4



0.0018
17.6



0.0020
17.5



0.0024
17.0



0.005
16.8



0.01
16.6



0.10
16.3



0.93
16.2




















TABLE 11







Bubble life [ms]
γ[mN/m]



















31
72.3



38
72.2



49
72.1



68
72.1



84
72.2



112
71.8



145
71.9



190
71.6



244
71.3



320
71.3



391
71



521
71



706
70.5



869
70.2



1224
70.4



1613
70



2102
70.3



2572
70.2



3329
69.5



4290
69.2



5506
68.5



6850
67.5



9319
65.7



11716
64.2



15108
60



19279
55.8



24035
50.2



30865
40.8



40016
32.1



55320
24.4










Example 8
Synthesis of the sulfotricarballylate of the Formula (Ia-5)
The sulfotricarballylate of the formula (Ia-5) is prepared by the process described in Example 1.
Empirical formula: C30H16F39O9SNa, M=1316.436 g/mol
1H-NMR (300 MHz; in DMSO-d6):
4.53-4.25 (m); 4.13 (d); 4.06 (d); 3.69-3.60 (m); 3.54-3.46 (m); 3.27 (ddd); 3.04-2.96 (m); 2.61-2.42 (m) ppm.
19F-NMR (282 MHz; in DMSO-d6):
−81.74 to −82.27 (m); −113.61 to −114.41 (m); −122.50 (s); −123.29 to −124.35 (m);
−126.74 to −127.31 (m) ppm.
MS (LC-ESI-MS negative):
RT: 11.91 (1293 [M−H]−)
Both the static surface tension as described in Example 2 and the dynamic surface tension as described in Example 3 are subsequently determined. The results are shown in Tables 12 and 13.










TABLE 12







c [%]
γ[mN/m]



















0.0001
71.9



0.001
71.5



0.01
71.4



0.10
52.9



0.98
54.5




















TABLE 13







Bubble life [ms]
γ[mN/m]



















31
72.8



38
72.9



49
72.8



64
72.8



86
72.9



110
72.7



146
72.7



187
72.9



244
72.9



319
73.1



393
73.2



524
73.3



715
73.4



890
73.3



1257
73.1



1614
72.9



2142
73



2536
73



3283
72.8



4222
72.8



5476
72.8



7128
72.9



9188
72.7



11868
72.7



15248
72.5



20919
72.5



26720
72.3



34303
72.3



44207
72.1



60491
72.2










Example 9
Synthesis of the sulfotricarballylate of the Formula (Ia-6)
The sulfotricarballylate of the formula (Ia-6) is prepared by the process described in Example 1.
Empirical formula: C30H22F33O12SNa, M=1256.492 g/mol
1H-NMR (400 MHz; in DMSO-d6):
4.28-4.05 (m); 3.91 (d); 3.84 (d); 3.82-3.69 (m); 3.51-3.45 (m); 3.39-3.30 (m); 3.25-3.09 (m); 3.02 (dd); 2.83 (dd) ppm.
19F-NMR (376 MHz; in DMSO-d6):
−80.94 to −81.23 (m); −119.39 to −119.96 (m); −123.34 to −123.87 (m); −126.30 to −126.76 (m) ppm.
MS (LC-ESI-MS negative):
RT: 11.38 (1233 [M−H]−)
Both the static surface tension as described in Example 2 and the dynamic surface tension as described in Example 3 are subsequently determined. The results are shown in Tables 14 and 15.










TABLE 14







c [%]
γ[mN/m]



















0.0001
72.2



0.0011
72.1



0.0020
65.0



0.0023
60.6



0.0033
44.0



0.0038
26.8



0.0050
15.8



0.0100
15.7



0.10
15.4



1.00
15.4




















TABLE 15







Bubble life [ms]
γ[mN/m]



















31
71.7



40
71.4



51
71.4



64
70.9



84
70.9



111
70.9



144
70.4



186
70.4



244
70.1



322
69.8



398
69.7



525
69.6



715
69.5



934
68.7



1221
67.7



1597
67.2



2099
66



2501
65.3



3243
64.3



4142
62.3



5208
61



7135
58.1



8938
55.7



11481
53.5



15165
50.3



19619
48.2



24941
46.1



33879
44



41071
41.8



54632
40.7

## Claims

1. A compound of the formula (I)



where either:
(A) the groups Zi (Z1, Z2 and Z3) are, independently of one another, branched or unbranched alkyl groups or groups of the structure Ri(A(CR1R2)ci(CR3R4)c′i)di—, where the respective indices ci and c′i are, independently of one another, 0-10 and di=1-5, where Ri is a branched or unbranched, fluorine-containing alkyl radical, R1 to R4 are, independently of one another, hydrogen or a branched or unbranched alkyl group, ci and c′i are not simultaneously 0, and A=O, S and/or N,

Y1 is an anionic polar group and Y2 is a hydrogen atom, or Y1 is a hydrogen atom and Y2 is an anionic polar group,
X is a cation,
and at least one of the groups Zi is a group of the structure Ri(A(CR1R2)ci—(CR3R4)c′i)di—; or
(B) the groups Zi (Z1, Z2 and Z3) are, independently of one another, branched or unbranched alkyl groups or groups of the structure Ri(A(CR1R2)ci(CR3R4)c′i)di—, where the respective indices ci and c′i are, independently of one another, 0-10 and di=0-5, where Ri is a branched or unbranched, fluorine-containing alkyl radical, R1 to R4 are, independently of one another, hydrogen or a branched or unbranched alkyl group, ci and c′i are not simultaneously 0, and A=O, S and/or N,

Y1 is an anionic polar group and Y2 is a hydrogen atom, provided that, when Y1 is the anionic polar group sulfonate, —SO3−, Z1, Z2 and Z3 are not simultaneously —CH2(CF2)3CF2H, —CH2(CF2)2CF3, or —CH2CF2CHFCF3,
X is a cation
and at least one of the groups Zi is a group of the structure Ri(A(CR1R2)ci—(CR3R4)c′i)di—.

2. A compound according to claim 1, wherein the variables in the formula (I) have the following meanings:
the groups Zi (Z1, Z2 and Z3) are, independently of one another, branched or unbranched alkyl groups or groups of the structure Ri(O(CH2)ci)di, where the respective indices ci=2-10 and di=0-5, and where Ri is a branched or unbranched, fluorine-containing alkyl radical,
Y1 is an anionic polar group and Y2 is a hydrogen atom, or vice versa Y1 is a hydrogen atom and Y2 is an anionic polar group,
X is a cation,
and at least one of the groups Zi is a group of the structure Ri(O(CH2)ci)di.

3. A compound according to claim 1, wherein the branched or unbranched alkyl groups for Zi contain 1 to 10 carbon atoms.

4. A compound according to claim 1, wherein X is a monovalent cation or an alkali metal cation.

5. A compound according to claim 1, wherein the compound has two or three fluorinated groups Zi.

6. A compound according to claim 1, wherein Z1, Z2 and Z3 are, independently of one another, F3C(CF2)ai(CH2)bi(O(CH2)ci)di— groups, where ai=0-2, bi=1-6, ci=2-10, and di=0-5.

7. A compound according to claim 1, wherein Y1 or Y2 is a sulfonate group —SO3−.

8. A compound according to claim 1, wherein Z1=Z2=Z3=F3C(CF2)ai(CH2)bi(O(CH2)ci)di, where ai=1-2, bi=1-2, ci=2, and di=1, Y1 is a sulfonate group —SO3−, Y2 is a hydrogen atom, and X=Na+.

9. A compound of the formula (Ia) or (Ib):



where Z1=Z2=Z3 and all Z, are selected from Ri(O(CH2)ci)di—, where ci=2, di=1-3, and Ri=CF3CF2CH2— or CF3CF2CF2CH2—.

10. A composition comprising a compound according to claim 1 as a surface-active agent, in a paint or coating composition, a printing ink, a wax or a polish.

11. A paint or coating composition comprising at least one compound according to claim 1 and a vehicle which is suitable for a paint or coating composition, and optionally further active substances.

12. A process for the preparation of a compound according to claim 1, comprising a) an esterification of aconitic acid or citric acid or the anhydride or acid chloride thereof using one or more alcohols of the formula ZiOH (II), and b) an addition reaction, onto the olefinic double bond or derivitization of the OH group, where the alcohols contain groups Zi according to claim 1.

13. A compound of the formula (III)



where
the groups Zi (Z1, Z2 and Z3) are, independently of one another, branched or unbranched alkyl groups or groups of the structure Ri(A(CR1R2)ci(CR3R4)c′i)di—, where the respective indices ci and c′i are, independently of one another, 0-10 and di=0-5, where Ri is a branched or unbranched, fluorine-containing alkyl radical, R1 to R4 are, independently of one another, hydrogen or a branched or unbranched alkyl group, and A=O, S and/or N, and at least one of the groups Zi is a group of the structure Ri(A(CR1R2)ci(CR3R4)c′i)di—, where ci and c′i are not simultaneously 0.

14. A compound according to claim 13, wherein Z1, Z2 and Z3 are, independently of one another, F3C(CF2)ai(CH2)bi(O(CH2)ci)di— groups, where ai=0-6, bi=1-6, ci=2-10, and di=0-5.

15. A method for the synthesis of fluorinated polymers which comprises polymerizing a compound of the formula (III) of claim 13 as a monomer or comonomer.

16. A compound according to claim 1, wherein the branched or unbranched alkyl groups for Zi contain 3 to 8 carbon atoms.

17. A compound according to claim 1, wherein X is the monovalent cation H+ or the alkali metal cation Na+ or NR4+, where R=H or C1-C6-alkyl, and each R may be identical or different.

18. A compound according to claim 1, wherein the compound has three fluorinated groups Zi.

19. A compound according to claim 1, wherein Z1, Z2 and Z3 are, independently of one another, F3C(CF2)ai(CH2)bi(O(CH2)ci)di— groups, where ai=1-2, bi=1-2, ci=2, and di=1.

20. A compound according to claim 6, wherein Z1, Z2 and Z3 are the same groups.

21. A compound according to claim 1, wherein Y1 is a sulfonate group, —SO3−.

22. The process of claim 12, wherein the esterification (a) is conducted in the presence of a catalyst and the addition reaction b) is by addition of sodium hydrogensulfite onto the olefinic double bond.

23. A compound according to claim 13, wherein Z1, Z2 and Z3 are, independently of one another, F3C(CF2)ai(CH2)bi(O(CH2)ci)di— groups, where ai=1-2, bi=1-2, ci=2, and di=1-3.

24. A compound according to claim 14, wherein Z1, Z2 and Z3 are the same F3C(CF2)ai(CH2)bi(O(CH2)ci)di— group.

25. A compound according to claim 1, wherein
R1 to R4 are, independently of one another, hydrogen or a C1-4-alkyl group,
ci and c′i are, independently of one another, 0-6, where ci and c′i are not simultaneously 0, and
di is 1-3.

26. A compound according to claim 1, which is a compound of formula (Ia-4) or formula (ia-5)