WO2008000680A1

WO2008000680A1 - Fluorous telomeric compounds and polymers containing same

Info

Publication number: WO2008000680A1
Application number: PCT/EP2007/056176
Authority: WO
Inventors: Hans Gotz; Wolfgang Knaup
Original assignee: Clariant International Ltd
Priority date: 2006-06-27
Filing date: 2007-06-21
Publication date: 2008-01-03
Also published as: TW200808835A

Abstract

Claimed are fluorous telomeric compounds of the formula RF - A - CXY - Z (IV), where RF is a perfluoroalkyl radical of 1 to 20 carbon atoms, A is a group of the formulae (I) or (II), Z is CH2OR3, or COO- 1/q Mq+ or CON(R4)R5OR3; X and Y are H, Cl or F; R1 is CF3, OR2, Cl, Br or I; R2 is perfluoromethyl, perfluoropropyl or perfluoropropyloxypropyl; R3 is H or COCR6=CH2; R4 is H or alkyl of 1 to 6 carbon atoms; R5 is alkylene of 1 to 13 carbon atoms; R6 is H or CH3'; M is H or a metal cation or an ammonium cation or a substituted ammonium cation; q is the valency of M; a is from 0 to 10 and b is from 1 to 30. These compounds are copolymerized with further monomers. The copolymers thus obtained are useful for water-, oil- and soil-repellent finishing of fibrous substrates.

Description

FLUOROUS TELOMERIC COMPOUNDS AND POLYMERS CONTAINING SAME

Fluorochemicals are often used as surfactants or wetting agents and are widely used for the surface treatment of substrates. They find frequent utility for the oil-, water-, and soil-repellent finishing of fibrous substrates such as for example carpets, textiles, leather, nonwovens and paper and of hard substrates such as for example wood, metal or concrete. The imbibition of hydrophilic and hydrophobic liquids is reduced with substrates thus treated, and the removal of existing soils is promoted.

Perfiuoroalkyl iodides obtained via telomerization of telogens with fluorinated monomers such as tetrafiuoroethene, for example, are an important starting point for the preparation of fluorocompounds.

Unpublished German patent application 10 2006 001 218.6 describes fluorous telomeric compounds of the following formula:

R_P - A - [CH₂I₀CR₂R₃ - Z

in which Rp is a perfiuoroalkyl radical of 1 to 20 carbon atoms, A is a group of the formulae

R¹ is CF₃ OR₄, Cl, Br or I,

R₂ and R₃ are H, alkyl or aryl

R₄ is perfluoromethyl, perfluoropropyl or perfluoropropyloxypropyl X and Y are H, Cl or F Z is -OH, -OCOCH=CH₂ or -OCOCCH₃=CH₂ a is from 0 to 10, b is from 1 to 30 and c is from 1 to 30.

To be used as a surface-modifying substance, perfiuoroalkyl iodides are typically first converted with ethene into a perfluoroalkylethyl iodide. The perfluoroalkylethyl iodide can then be converted with suitable reagents into the corresponding perfluoroalkylethyl alcohol. From the perfluoroalkylethyl alcohols, then, the corresponding (meth)acrylate monomers of the formula I can be prepared.

R_FCH₂CH₂OCOCR=CH₂ (I)

The preparation of fluorous acrylates and methacrylates satisfying the formula I from various derivatives of acrylic acid and methacrylic acid respectively is well known and documented.

Copolymers prepared from these fluorous acrylates are particularly useful for modifying surfaces to be oil, water and soil repellent, for example for finishing textiles or for coating leather and paper.

The fluorous monomers of the formula II

R_FSO₂NR(CH₂)_nOCOCR=CH₂ (II)

are known for similar applications.

The fluorinated alkylsulphonic acid fluoride used in their synthesis is obtained via electrochemical fluorination.

It has been determined for both monomer types (I and II) that the coating of surfaces with longer and ideally straight-chain perfluoroalkyl chains which consist of 8-10 fluorinated carbon atoms leads to particularly low surface energies.

Fluorous compounds having a linear perfluoroalkyl chain with 8 fluorinated carbon atoms, including the monomers described above, can degrade to form perfluorooctanecarboxylic acid and perfluorooctanesulphonic acid, respectively. These degradation products are considered not further degradable and therefore are persistent. Moreover, these compounds are suspected of accumulating in living organisms. There have therefore been various proposals in recent years for preparing environmentally compatible perfluoroalkyl compounds.

WO 02/16306 describes branched fluorous (meth)acrylates having the formula III

R_F(R_F ')CHOCOCR=CH₂ (III)

having a straight-chain or branched perfluoroalkyl group R_F of 5 or fewer carbon atoms and a branched perfluoroalkyl chain Rp' of 3 to 5 carbon atoms. These compounds lead specifically to degradation products of low molecular weight and low toxicity.

It is known that shorter-chain perfluoroalkylsulphonic acid derivatives are more easily eliminated from the body of living organisms. The WO 03/062521 patent describes textile finishes based on perfiuorobutanesulphonic acid derivatives conforming to the formula II

R_FSO₂NR'(CH₂)_nOCOCR=CH₂ (II)

in lieu of perfluorooctanesulphonic acid derivatives having a partially branched perfluoroalkyl radical Rp of 4 fluorinated carbon atoms, n = 1, 2 and R' = H, alkyl and R = H, CH₃.

Compounds having a fluorinated alkyl radical of 4 carbon atoms and conforming to the formula I

R_FCH₂CH₂OCOCR=CH₂ (I)

are described in EP 1 632 542 Al . It is likely that the degradation products are more easily eliminated from the body of living organisms.

WO 02/34848 describes the use of polyoxetanes having trifluoromethyl groups or pentafluoroethyl groups as perfluoroalkyl radical. This class of compounds likewise represents environmentally compatible perfluoroalkyl-containing compounds used as fluorosurfactants or for coatings.

WO 2004/060 964 describes fluorinated polyethers having a molecular weight of greater than 750 g/mol, which are eliminated particularly easily from the body of living organisms. WO 03/100 158 describes the use of such alcohols and acrylates for finishing textiles.

However, it has emerged that the heretofore described proposals for environmentally friendly alternatives to perfiuoroalkyl compounds are less effective than them when used as a basis for oil- and water-repellent finishes. This is reflected in the values achieved for water repellency and oil repellency and in coating durability.

It is an object of the present invention to provide an alternative to polyfiuoroalkyl- containing compounds and their derivatives which have no bioaccumulative effect. Its performance profile further includes a high effectivity when they are used for oil- and water repellent coatings. In addition, the compounds have to remain handlable on an industrial scale.

It has now been found that, surprisingly, polyfluoroalkyl compounds as hereinbelow defined lead to oil- and water-repellent coatings of high efficiency and durability and are also environmentally compatible.

The invention accordingly provides fluorous carboxylic acids and/or fluorous alcohols and derivatives thereof having molecular weights of greater than 750 g/mol.

The invention further provides fluorous compounds which, owing to their being composed of a polyfluoroalkyl chain which is partly branched and partly linear, melt at lower temperatures than their molecular weight equivalents consisting of a linear polyfluoroalkyl chain.

The invention further provides fluorous carboxylic acids, carboxylic acid salts and ester derivatives which are prepared from the corresponding polyfluorous alkyl alkyl iodides. The present invention provides fluorous telomeric compounds of the formula IV:

R_F- A - CXY - Z (IV)

where R_F is a perfluoroalkyl radical of 1 to 20 carbon atoms, A is a group of the formulae

Z is CH₂OR³, or COO^" 1/q M^q+ or CON(R⁴)R⁵OR³

X and Y are H, Cl or F

R¹ is CF₃, OR², Cl, Br or I,

R² is perfluoromethyl, perfluoropropyl or perfluoropropyloxypropyl

R³ is H or COCR⁶=CH₂

R I⁴⁴ is H or alkyl of 1 to 6 carbon atoms

R⁵ is alkylene of 1 to 13 carbon atoms

R⁶ is H or CH₃

M is H or a metal cation or an ammonium cation or a substituted ammonium cation q is the valency of M a is from 0 to 10 and b is from 1 to 30.

Preference is given to fluorous compounds of the formula IV which have a molecular weight of greater than 750 g/mol. Particular preference is given to compounds of the formula IV which have a molecular weight of greater than 1000 g/mol.

The polyfluoroalkyl radical Rp can be a polyfluoroalkyl group having a unitary chain length or a mixture of polyfluoroalkyl groups having different chain lengths, for example CF₃, C₂F₅, C₃F₇, C₄F₉, C₆F_n, C₈F_n, Ci₀F_2I, Ci₂F₂₅, Ci₄F₂₉ and Ci₆F_3I groups. The polyfluoroalkyl radical can be branched or unbranched.

Preference is given to compounds in accordance with the invention which have a saturated polyfluoroalkyl radical Rp which has a chain length of 1 to 20 fluorinated carbon atoms and comprises at least one terminal CF₃ group.

Particular preference is given to a fully fluorinated carbon chain Rp of 1 to 3 or 4 to 16 fluorinated carbon atoms.

X and Y may independently be H, Cl or F. Preferably, X and Y are fluorine atoms. Alternatively, X is a fluorine atom and Y is a chlorine atom, or X and Y are hydrogen atoms.

Preferably a is from 0 to 10 and more preferably from 0 to 5.

Preferably b is from 1 to 30 and more preferably a + b > 3.

The functional group Z is either a carboxylic acid, a carboxylic acid salt, a carboxamido alcohol, a carboxamidoalkyl (meth)acrylate, an alcohol, a methacrylate or acrylate.

R¹ is a sterically voluminous group which has a crystallization-inhibiting effect on the polyfluoroalkyl chain. Particular preference is given either to a perfluoromethyl group, to a perfluoroalkyl ether group or to a chlorine, bromine or iodine atom. A perfluoromethyl group is most preferable.

Preferably, R is a perfluoromethyl group, a perfluoropropyl group or a perfluoropropyloxypropyl group. A perfluoromethyl group is most preferable.

R³ is either hydrogen or COCR⁶=CH₂.

R⁴ is hydrogen or an alkyl chain of 1 to 6 carbon atoms, preferably a methyl or an ethyl group.

R⁵ is an alkylene chain of 1 to 13 carbon atoms, preferably an ethylene group.

R⁶ is either hydrogen or a methyl group. The compounds of the invention are prepared from the corresponding polyfluoroalkyl iodides in a multistage process.

In the first step of the process, known as telomerization, a fluorous compound (telogen) capable of transferring a free radical chain is reacted with at least one fluorinated monomer (taxogen) via a free radical forming mechanism at 20-250⁰C to form the telomer of the formula

R_F - A - I.

Useful telogens include fluorous alkyl compounds having a group to be scissioned free- radically, for example fluorous alkyl iodides, bromides, thiols, thioethers and alcohols. Preference is given to perfiuoroalkyl iodides having a unitary chain length or to a mixture of perfiuoroalkyl iodides having different chain lengths. The perfiuoroalkyl radical can be branched or unbranched, for example perfluoromethyl iodide, perfiuoroethyl iodide, n-perfluoropropyl iodide, isoperfluoropropyl iodide, n- perfluorobutyl iodide, isoperfiuorobutyl iodide, tert-perfluorobutyl iodide and isomers of perfluorohexyl iodide, perfiuorooctyl iodide, perfiuorodecyl iodide and perfiuorododecyl iodide and so on.

Preference is given to perfiuoroalkyl iodides in accordance with the invention having a chain length of 1 to 20 carbon atoms and at least one terminal CF₃ group.

Particular preference is given to perfluoromethyl iodide, perfiuoroethyl iodide, perfluoropropyl iodide or perfluoroisopropyl iodide or a technical grade mixture of various perfiuoroalkyl iodides, having chain lengths of 6 to 16 fluorinated carbon atoms or 8 to 16 fluorinated carbon atoms and an average chain length of about 7.5 fluorinated carbon atoms or about 9 fluorinated carbon atoms.

The addition of the taxogens onto the telogen results in the building up of higher molecular weights. The telomer thus formed consists of a perfiuoroalkyl chain having a terminal iodine group. The way the taxogens are incorporated in the telomer differs according to which of the following three variants is chosen.

In the first variant, initially only a fluorinated unsaturated monomer

is added onto the telomer. The product then adds under the telomerization conditions the monomers of the formula CF₂=CXY. The telomer thus obtained has the formula

and exhibits blockwise incorporation of the monomers.

In the second variant, initially only a fluorinated unsaturated monomer CF₂=CXY is added. The product then adds under the telomerization conditions the monomers of the formula CF₂=CFRi . The resulting telomer

R_F

likewise exhibits blockwise incorporation of the monomers, but with the added monomers in the reverse order.

In the third variant, concurrent addition of a mixture of the two monomers results in random incorporation of the monomers CF₂=CFRi and CF₂=CXY.

Examples of compounds of the formula CF₂=CFRi are: chlorotrifluoroethene, bromotrifluoroethene, iodotrifluoroethene, perfluoromethyl vinyl ether, perfiuoroethyl vinyl ether, perfiuoropropyl vinyl ether, perfluoropropyloxypropyl vinyl ether and also branched and unbranched perfluoroolefins having a terminal double bond, examples being hexafluoropropene, 1-perfiuorobutene, 1-perfluorohexene or perfiuorooctene. Examples of compounds of the formula CF₂=CXY are for example tetrafluoroethene, vinylidene fluoride, chlorotrifluoroethene, trifluoroethene, l,l-dichloro-2,2- difluoroethene and l-chloro-2,2-difluoroethene.

In the case of iodine-containing compounds, free radicals which initiate the telomerization reactions can be generated by sources capable of forming free radicals. Useful sources for forming free radicals include light or heat. The light source typically has its maximum in the infrared to ultraviolet region. Free radical formation due to heat typically takes place at temperatures between 100⁰C and 250⁰C.

Useful sources for forming free radicals further include free radical initiators of the chemical kind, which are also capable of lowering the reaction temperature required for free radical formation to between 0⁰C and 150⁰C, examples being organic or inorganic peroxides, azo compounds, organic and inorganic metal compounds and metals and also combinations thereof. Particular preference is given to persulphates, fluorinated and nonfluorinated organic peroxides, azo compounds and metals such as for example Ru, Cu, Ni, Pd and Pt.

The telomerization can be carried solventlessly, in solution, in suspension or emulsion. The reaction without a solvent or in emulsion is particularly preferred. In the case of the reaction in emulsion, the telogen is first converted with the aid of surfactants into an aqueous emulsion. The emulsion can be stabilized by anionic, cationic, nonionic or amphoteric surfactants and combinations thereof. Fluorosurfactants are particularly suitable for example. The reaction typically takes place at elevated temperature through addition of the taxogens and free radical initiators. Additional components can increase the reaction yield, examples being small amounts of aqueous solutions of sulphites, bisulphites or dithionates.

The polyfluoroalkyl iodide obtained via telomerization is next converted into a polyfluoroalkyl carboxylic acid of the formula IV (Z = COOH)

R_F - A - CXY - Z (IV). Various preparative methods can be used for the oxidation to polyfiuoroalkyl carboxylic acid. One reaction, described in DE 3 043 249 for example, involves polyfiuoroalkyl iodides being oxidized with fuming sulphuric acid at temperatures of 100 to 180⁰C to form polyfiuoroalkyl carboxylic acid.

The polyfiuoroalkyl carboxylic acid salts of formula IV where Z = COO^" 1/q M^q+ are obtained by reaction of the polyfiuoroalkyl carboxylic acids with a base such as for example lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidinium hydroxide, caesium hydroxide, ammonium hydroxide or tetrabutylammonium hydroxide.

The polyfiuoroalkyl carboxylic acid is used as a starting material for preparing various alcohols according to the formula IV Z = CH₂OH and Z = CON(R⁴)R⁵OH.

In the first version, the polyfiuoroalkyl carboxylic acid is hydrogenated, as described for example in DE 22 22 682, in the presence of suitable catalysts and hydrogen at temperatures of 150 to 220⁰C to form lH,lH-polyfluoroalkyl alcohol (Z = CH₂OH). Metal and metal oxide catalysts are preferred. Ruthenium catalysts are particularly preferred.

In the second version, a polyfiuoroalkyl carboxamido alcohol is prepared by reaction of the polyfiuoroalkyl carboxylic acid with an amino alcohol. This reaction can be carried out with or without solvent at temperatures between 20⁰C and 80⁰C. The amino alcohols used can be primary amino alcohols such as for example 2-aminoethanol, 3- aminopropanol, 4-aminobutanol, 2-amino-l-butanol, 5-aminopentanol, 2-amino-l- pentanol, 6-aminohexanol or secondary amino alcohols such as for example 2- methylaminoethanol, 3-methylaminopropanol, 4-methylaminobutanol, 2-methylamino- 1-butanol, 5-methylaminopentanol, 2-methylamino-l-pentanol, 6-methylaminohexanol, 2-ethylaminoethanol, 3-ethylaminopropanol, 4-ethylaminobutanol, 2-ethylamino-l- butanol, 5-ethylaminopentanol, 2-ethylamino-l-pentanol, 6-ethylaminohexanol, 2- propylaminoethanol, 3-propylaminopropanol, 4-aminobutanol, 2-propylamino-l- butanol, 5-propylaminopentanol, 2-propylamino-l-pentanol, 6-propylaminohexanol, 2- butyaminoethanol, 3-butylaminopropanol, 4-butylamino butanol, 2-butylamino-l- butanol, 5-butylaminopentanol, 2-butylamino-l-pentanol and 6-butylaminohexanol. Particular preference is given to 2-aminoethanol, 2-methylaminoethanol, 2- ethylaminoethanol and 3-propylaminoethanol.

The lH,lH-polyfluoroalkyl alcohols and polyfluoroalkyl carboxamido alcohols obtained in this way can be reacted with (meth)acrylate esters, acids or acid chlorides to form the corresponding fluorous (meth)acrylates having the formulae

R_F - A - CXY - CH₂OCOCR⁶=CH₂

and

R_F - A - CXY - CON(R⁴)R⁵OOCOCR⁶=CH₂.

The reaction with the (meth)acrylate acid chlorides is typically carried out in the presence of a base such as triethylamine to bind hydrogen chloride formed. A suitable catalyst, for example a tin catalyst, can be used for the transesterification.

These acrylates and methacrylates can be copolymerized with nonfluorous polymerizable vinyl monomers and/or chlorine-containing polymerizable vinyl monomers and optionally one or more thermally crosslinkable or isocyanate-reactive monomers.

The invention also provides copolymers containing, based on the total weight of the copolymer: a) 20% to 97% by weight and preferably 40% to 90% by weight of a monomer of the formula IV where Z is CH₂OCOCR⁶=CH₂ or CON(R⁴)R⁵OOCOCR⁶=CH₂, b) 0% to 80% by weight and preferably 10% to 50% by weight of one or more nonfluorous polymerizable vinyl monomers and/or c) 0.5% to 20% by weight and preferably 1% to 10% by weight of one or more thermally crosslinkable or isocyanate-reactive monomers.

The present invention further provides copolymers containing, based on the total weight of the copolymer: a) 40% to 90% by weight and preferably 45% to 85% by weight of a monomer of the formula IV where Z is CH₂OCOCR⁶=CH₂ or CON(R⁴)R⁵OOCOCR⁶=CH₂, b) 0% to 50% by weight and preferably 0.01% to 30% by weight of one or more nonfluorous polymerizable vinyl monomers and/or c) 0.5% to 20% by weight and preferably 1% to 10% by weight of one or more thermally crosslinkable or isocyanate-reactive monomers and d) 0.5% to 50% by weight and preferably 2% to 30% by weight of a chlorine- containing polymerizable vinyl monomer.

The optional comonomer (b) is not fluorous (does not contain fluorine) and is represented by a multiplicity of commercially available acrylates and methacrylates and styrene derivatives.

Examples of nonfluorinated comonomers are hydrocarbyl esters and amides of unsaturated carboxylic acids. These include for example the following esters and amides of acrylic acid, methacrylic acid, α-chloroacrylic acid, crotonic acid, maleic acid, fumaric acid and itaconic acid: vinyl, allyl, methyl, ethyl, propyl, isopropyl, n- butyl, isobutyl, t-butyl, hexyl, 3,3-dimethylbutyl, heptyl, octyl, isooctyl, lauryl, cetyl, stearyl, behenyl, cyclohexyl, bornyl, isobornyl, phenyl, benzyl, adamantyl, tolyl, (2,2- dimethyl-l-methyl)propyl, cyclopentyl, 2-ethylhexyl, 4-ethylcyclohexyl, 2-ethoxyethyl and tetrahydropyranyl.

Further nonfluorinated comonomers are allyl esters and vinyl esters such as for example allyl acetate, vinyl acetate, allyl heptanoate and vinyl heptanoate; alkyl vinyl ethers and alkyl allyl ethers such as for example cetyl vinyl ether, dodecyl vinyl ether, octadecyl vinyl ether and ethyl vinyl ether; α,β-unsaturated nitriles such as for example acrylonitrile, methacrylonitrile, α-chloroacrylonitrile, α-cyanoethyl acrylate; aminoalkyl (meth)acrylates such as for example N,N-diethylaminoethyl (meth)acrylate, N-t-butylaminoethyl (meth)acrylate; alkyl (meth)acrylates having an ammonium group such as for example 2-methacryloyloxyethyltrimethylammonium chloride; styrene and its derivative such as for example vinyltoluene, α-methylstyrene, CC- cyanomethylstyrene, chloromethylstyrene; olefinic hydrocarbons such as for example ethene, propene, isobutene, butadiene, isoprene; and (meth)acrylates of methoxy polyethylene glycols.

Particularly preferred optional comonomers (b) can be the following esters or amides of acrylic acid and methacrylic acid: methyl, ethyl, propyl, butyl, isobutyl, 2-ethylhexyl, myristyl, lauryl, octadecyl, methoxy poly(ethylene glycol) and methoxy poly(propylene glycol) as described above.

The comonomer (c) contains one or more crosslinkable groups. A crosslinkable group is a functional group capable of entering a reaction with the substrate and/or with a further polyfunctional compound added. Such crosslinkable groups can be: carboxylic acid groups, ethylenically unsaturated groups, hydroxyl groups, amino groups, N- alkylolamide groups, isocyanate groups or protected isocyanate groups. Examples of comonomers having one or more crosslinkable groups include unsaturated carboxylic acids and anhydrides of acrylic acid, methacrylic acid, α-chloroacrylic acid, crotonic acid, maleic acid, fumaric acid and itaconic acid, monomers including a hydroxyl group, for example hydroxyethyl (meth)acrylates and hydroxypropyl (meth)acrylates, hydroxybutyl (meth)acrylate, poly(ethylene glycol) mono(meth)acrylate, poly(propylene glycol) mono(meth)acrylate, poly(ethylene glycol)-co-poly(propylene glycol) mono(meth)acrylate, polytetrahydrofuran mono(meth)acrylate, N- hydroxymethyl(meth)acrylamide, hydroxybutyl vinyl ether. Further crosslinkable monomers are for example vinyl (meth)acrylate, allyl (meth)acrylate, N- methoxymethylacrylamide, N-isopropoxymethylacrylamide, N- butoxymethylacrylamide, N-isobutoxymethylacrylamide, glycidyl (meth)acrylate and α,α-dimethyl-m-isopropenylbenzyl isocyanate. Other examples are monomers which release isocyanates at elevated temperatures or under irradiation with light, examples being phenol-, ketoxime- and pyrazole-protected isocyanate-terminated alkyl (meth)acrylates.

The optional comonomer (d) is chlorine containing. Examples of chlorine-containing comonomers are halogenated olefinic hydrocarbons such as for example vinyl chloride, vinylidene chloride, 3-chloro-l -isobutene, 1-chlorobutadiene, 1,1-dichlorobutadiene and 2,5-dimethyl-l,5-hexadiene. Vinylidene chloride and vinyl chloride are particularly preferred optional comonomers (c).

The copolymer described hereby is typically prepared by a free radical polymerization technique, for example by solvent, emulsion, microemulsion or miniemulsion polymerization techniques. Variants of the emulsion polymerization are particularly preferred. The emulsion polymerization of the monomers takes place in the presence of water, surfactants and an optional organic solvent. The mixture can have been pre- emulsified before the polymerization, by means of a high pressure homogenizer or a similar apparatus. The polymerization is typically carried out at temperatures between 50⁰C and 150⁰C in the presence of a free radical initiator.

Various anionic, cationic, nonionic or amphoteric surfactants can be employed, alone or in combination. Examples of nonionic surfactants include poly(ethylene glycol) lauryl ether, poly( ethylene glycol) tridecyl ether, poly(ethylene glycol) cetyl ether, poly(ethylene glycol)-co-poly(propylene glycol) cetyl ether, poly(ethylene glycol) stearyl ether, poly(ethylene glycol) oleyl ether, poly(ethylene glycol) nonylphenol ether, poly(ethylene glycol) octylphenol ether, poly(ethylene glycol) monolaurate, poly(ethylene glycol) monostearate, poly( ethylene glycol) monooleate, sorbitan monolaurate, sorbitan monostearate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan sesquioleate, sorbitan trioleate, poly(ethylene glycol) sorbitan monolaurate, poly(ethylene glycol) sorbitan monopalmitate, poly(ethylene glycol) sorbitan monostearate, poly(ethylene glycol) sorbitan monooleate, poly( ethylene glyco I)-Co- poly(propylene glycol), polyglycerol fatty acid esters, polyether-modified silicone oils and perfiuoroalkyl-ethylene oxide adducts. The amount of nonionic surfactant used ranges from 0.1 to 100 percent by weight, relative to the weight of the polymer.

Examples of the cationic surfactants in accordance with the invention are ammonium compounds based on saturated and unsaturated fatty acid amines, for example octadecylammonium acetate, dodecyltrimethylammonium chloride; ammonium compounds based on amino-functionalized polyethoxylates and polypropoxylates and their interpolymers such as for example polyoxyethylene laurylmonomethylammonium chloride; ammonium compounds based on arylamines such as for example biphenyltrimethylammonium chloride, imidazoline derivatives such as for example ammonium salts formed from tallow and imidazoline; silicone-based cationic surfactants and fluorine-based cationic surfactants. The amount of cationic surfactant used ranges from 0.1 to 100 percent by weight relative to the weight of the polymer.

Examples of the anionic surfactants in accordance with the invention include fatty alcohol sulphates, for example sodium dodecylsulphate and poly(ethylene glycol) lauryl ether sulphate; alkylsulphonates such as for example sodium laurylsulphonate; alkylbenzenesulphonates, for example nonylphenol ether sulphates, sulphosuccinates, for example sodium hexyl diether sulphosuccinate; fatty alcohol phosphates, for example sodium laurylphosphate and fatty acid salts, such as for example sodium stearic acid salt. The amount of anionic surfactant used ranges from 0.1 to 100 percent by weight, relative to the weight of the polymer.

Examples of free radical initiators are organic or inorganic peroxides, azo compounds, organic and inorganic metal compounds and metals and also combinations thereof. Particular preference is given to azo compounds such as azobisisobutyronitriles (AIBNs), azobisvaleronitrile and azobis(2-cyanovaleric acid), 2,2'-azobis(2- amidinopropane) dihydrochloride; hydroperoxides such as cumene hydroperoxide, t- butyl hydroperoxide and t-amyl hydroperoxide, dialkyl peroxides such as di-t-butyl peroxide and dicumyl peroxide, peroxyesters such as t-butyl perbenzoate and di-t-butyl peroxyphthalate, diacyl peroxides, such as benzoyl peroxide and lauroyl peroxide; inorganic peroxides such as ammonium persulphate and potassium persulphate and also combinations of the specified compounds with organic or inorganic metal compounds and metals.

A chain transfer agent can be used in the polymerization, an example being an alkylthiol.

Examples of the organic solvent in the solvent and emulsion polymerization are: ketones such as for example acetone, methyl ethyl ketone and methyl isobutyl ketone; alcohols such as for example ethanol, isopropanol and butanol, polyalcohols such as for example 1,3-butanediol, 1,6-hexanediol, ethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol and glycerol; ethers and esters of polyalcohols, such as for example dipropylene glycol mono methyl ether, tripropylene glycol mo no methyl ether, triethylene glycol dimethyl ether and diethylene glycol monobutyl ether acetate; esters such as for example ethyl acetate, propyl acetate, butyl acetate, dibutyl adipate and dibutyl succinate; hydrocarbons and halogenated hydrocarbons such as for example toluene, xylene, octane, perchloroethylene and l,3-dichloro-2,2,3,3,3- pentafluoropropane.

The preferred solids content for the polymer dispersion prepared is between 20 and 40 percent by weight.

The fluorous copolymers containing a fiuorous monomer of the formula IV, where Z is CH₂OCOCR⁶=CH₂ or CON(R⁴)R⁵OOCOCR⁶=CH₂, are suitable for coating fibrous substrates such as for example carpets, textiles, leather, nonwovens or paper or hard substrates such as for example wood, metal or concrete. They endow these substrates with water-, oil- and soil-repellent properties.

The invention thus also provides a process for surface treatment of fibrous substrates with an effective amount of the fluorous aqueous dispersion.

The content of the preparation for finishing textiles and other sheetlike structures in accordance with this invention is chosen so that sufficient repellent properties are transferred to the treated substrate. The wet pick-up was determined by weighing the finished specimens before and after application.

The fluorous textile- finishing agents according to the invention can be used together with other additives, including water-repellent materials, such as for example waxes, silicones, zirconium compounds or stearic acid salts, and also other oil-repellent materials, surfactants, insecticides, flame retardants, antistatic additives, plasticizers, dye fixatives and crease resist additives in an amount which does not impair fixing on the textile and the stability of the composition.

The fluorous textile- finishing agents according to the invention can be crosslinked by addition of reactive additives such as for example melamine resins, protected isocyanates or epoxides.

The fibrous substrates to be coated with the fiuorous polymeric dispersion can be for example carpets, textiles, leather, nonwovens and paper. These consist inter alia of natural fibres such as for example cotton, linen and silk; of synthesis fibres such as for example polyamides, polyesters, polyurethanes, polyolefins, poly(meth)acrylates, poly(vinyl chlorides), poly( vinyl alcohols); semisynthetic fibres such as for example rayon or acetate; inorganic fibres such as for example glass fibres or ceramic fibres or any desired combination of the specified fibres or any desired combination of woven products composed of these materials.

For coating, the substrate is typically immersed in a dilute dispersion consisting of copolymer and optional additives. Alternatively, the dilute dispersion can be sprayed onto the substrate. The saturated substrate is subsequently pressed by a system of rolls to remove excess dispersion, dried in an oven and crosslinked at a temperature and for a time sufficient to ensure crosslinking on the treated substrate. This crosslinking process is typically carried out at temperatures between 50 and about 190⁰C. In general, a temperature of about 120⁰C to 180⁰C and in particular of about 130⁰C to 170⁰C for a period of 20 seconds up to 10 minutes is suitable, preference being given to 5 seconds to 5 minutes.

A further alternative for applying the preparation to a substrate is foam application wherein the preparation is applied to the substrate as a foam which is then dried and crosslinked. For foam application, the preparation is typically added in a concentrated form which has been admixed with an additional foamer. A highly concentrated preparation for foam application typically contains the fiuoropolymer in an amount of up to 20% by weight.

For the finishing on textiles, these can be examined in specific tests for their water-, isopropanol- and oil-repellent properties before and after washing.

Water repellency is attained by the spray test as per AATCC Standard Test Method 22. Distilled water is sprayed onto the textile substrate to be tested and a subsequent visual comparison of the pattern of wetting with reference pictures of an evaluation standard recited in the test method was used to generate a numerical value. The reported numerical values relate to the appearance of the surface after spraying with water and have the following connotation (Table 1):

Table 1

A second test with a series of water-isopropanol test solutions can be used to determine the isopropanol repellency (IPA) of a substrate. The reported IPA rating is the highest numbered test solution where the fabric is not wetted within 10 seconds and the drops still have the shape of a sphere or a hemisphere. Wetted substrates or substrates which are only repellent to 100% water (0% isopropanol), i.e. the least wetting test solution, are rated 0, whereas substrates which are repellent to 100% isopropanol (0% water) are rated 10. Intermediate ratings can be assigned as well.

Oil repellency as per AATCC Standard Test Method 118 tests the ability of a substrate to repel oily soiling, higher ratings in the assessment scale denoting better repellency of such soil, in particular of oily liquids. In the test, drops of standardized test liquids, consisting of a selected series of hydrocarbons having different surface tensions, are applied in succession to the surface of the specimen to be tested, by careful pipetting, and the wetting is visually assessed after a defined contact time. The oil repellency value corresponds to the highest numbered test liquid which causes no wetting of the surface. The standard test liquids have the following composition (Table 2):

Table 2

Note: Nujol is a mineral oil from Plough Inc. having a Saybolt viscosity of 360/390 at 38°C and a specific weight of 0.880/0.900 at 15°C.

Prior art FC polymers are currently giving oil repellency values of 6; however, a rating of 5 is usually already considered excellent.

Examples

The examples which follow illustrate the subject matter and advantages of the invention, but the materials and amounts cited in the examples shall not be viewed as limiting.

Syntheses

Example 1: Synthesis of C₈Fi7(CF2CF(CF3))a(CF2CF2)_bI

An emulsion of 110 g (0.18 mol) of Fluowet 1812* (Clariant), 15 g of Fluorolink C (Solvay Solexis), 5 g of ammonia and 90 g of water was prepared by intensive stirring at 60⁰C and introduced into an autoclave as an initial charge together with 2.5 g of ammonium persulphate. The pressure test was followed by repeated purging with nitrogen. During the heating-up phase to 80⁰C, hexafluoropropene and tetrafluoroethene were added to the stirred emulsion in a ratio of 3:5 up to an overall pressure of 17 bar. The pressure is kept constant at 17 bar until 82.5 g (0.55 mol) of hexafluoropropene and 90 g (0.90 mol) of tetrafluoroethene have been added. After a drop in pressure, the autoclave is cooled down to room temperature and the fluorochemical phase is separated off by addition of salt and washed. The low molecular weight constituents are separated off by distillation. The iodine content of 11.2% suggests an average molecular weight of about 1400 g/mol.

¹⁹F NMR (solvent CDCyC₆F₆, versus CFCl₃): -59.8 (2F, -CF₂I), -71.8 to -77.0 (in each case 3F, -CF-CF₃), -81.9 (3F, -CF₂-CF₃), -110.2 to -126.9 (in each case 2F, -CF₂-), - 184.6 to -185.5 (in each case IF, -CF(CF₃)-).

It is evident from the ¹⁹F NMR spectrum that about 2 molecules of hexafluoropropene have been incorporated per perfluoroalkyl iodide used.

* The compound designated 1812 is a perfluoroalkyl iodide mixture having 6 to 14 fluorinated carbon atoms per molecule having an average chain length of about 9 fluorinated carbon atoms.

Fluorolink C is a perfluoro polyether carboxylic acid.

Examples 2 to 9: Synthesis of polyfluoroalkyl iodides

Example 1 was repeated to prepare corresponding polyfluoroalkyl iodides (Examples 2 to 9). The results of the syntheses are shown in Table 3.

Table 3

Telomerization reactions to prepare polyfluoroalkyl iodides having the general composition:

Ex. No. RF RF a b C d M_n

Iodide [mol] [mol] [mol] [mol] [mol] *

[kg/mo 1]

2 (CF₃)₂CF- 0.25 0.55 2.23 - - 1.3

3 C₈Fi₇- 0.25 0.71 - 3.06 - 1.5

4 C₂F₅- 0.20 0.43 4.04 - - 2.4

5 C₈Fi₇- 0.35 0.68 - - 1.75 1.2

6 1812- ** 0.30 - 2.49 - 1.23 1.7

7 C₈F₁₇- 0.25 - - 1.98 1.01 1.3

8 (CF₃)₂CF- 0.18 0.20 - 1.83 - 0.9

9 1612- ** 0.22 0.87 1.32 1.5

* determined from iodine content

** the compounds designated Fluowet 1612 and Fluowet 1812 are perfiuoroalkyl iodide mixtures from Clariant, each having 6 to 14 fluorinated carbon atoms per molecule having an average chain length of about 7.5 fluorinated carbon atoms and 9 fluorinated carbon atoms respectively.

Example 10: Synthesis of C₈Fi₇(CF₂CF(CF₃))_a(CF₂CF₂)_bCF₂COOH

146.5 g (0.11 mol) of the polyfluoroalkyl iodide from Example 1, 2.1 g of zinc sulphate and 105.5 g of oleum (65% SO₃) were weighed into a shaker autoclave and reacted at 155°C for 8 hours. After the reaction, the reaction mixture was cooled down and admixed with 1,1,2-trichloroethane. After shaking, the lighter phase is separated off and carefully hydro lysed with warm water. Repeated washing with warm water left 110.7 g (0.10 mol) of polyfluoroalkyl carboxylic acid.

The acid number was 48.9 mg of KOH/g of product. Examples 11 to 18: Synthesis of polyfluoroalkyl carboxylic acids

Example 10 was repeated to prepare corresponding polyfluoroalkyl carboxylic acids (Examples 11 to 18). The results of the syntheses are shown in Table 4.

Example 19: Synthesis of C₈Fi₇(CF₂CF(CF₃))_a(CF₂CF₂)_bCF₂CH₂OH

2.0 g of H 101 B/W ruthenium catalyst (Degussa) and 90.2 g of the polyfluoroalkyl carboxylic acid from Example 10 were introduced as an initial charge under nitrogen. Following a pressure test with 50 bar of nitrogen, 40 bar of hydrogen were injected. The reaction mixture was maintained at 140⁰C for 20 hours. After decompression, the product was filtered at 70⁰C, washed with hot water and the volatile constituents were removed to obtain 85 g of polyfluoroalkyl alcohol.

The OH number was 46.7 mg of KOH/g of product.

Example 20: Synthesis of C₈Fi₇(CF₂CF(CF₃)_a(CF₂CF₂)_bCF₂CON(CH₃)CH₂CH₂OH

A 250 ml four neck flask was charged with 86.4 g of the polyfluoroalkyl carboxylic acid from Example 10 at 60⁰C. 15.4 g of N-methylaminoethanol were added in the course of 30 minutes with stirring. The reaction mixture was slowly heated to 180⁰C. Water formed was removed via a Dean-Stark apparatus. The reaction mixture was stirred at that temperature for a further 4 hours for supplementary reaction. The reaction mixture was cooled down to 70⁰C and mixed with 150 ml of ethanol preheated to 70⁰C and precipitated in water. Washing and drying left 83.7 g of polyfluoroalkyl amido alcohols.

The OH number was 48.2 mg of KOH/g of product.

Examples 21 to 24: Synthesis of polyfluoroalkyl alcohols

Example 19 was repeated to prepare corresponding polyfluoroalkyl alcohols (Examples 21 to 24). The results of the syntheses are reported in Table 4. Examples 25 to 28: Synthesis of polyfluoroalkyl amido alcohols

Example 20 was repeated to prepare corresponding polyfluoroalkyl amido alcohols (Examples 25 to 28). The results of the syntheses are reported in Table 4.

Example 29: Synthesis of C₈Fi₇(CF₂CF(CF₃)_a(CF₂CF₂)_bCF₂CH₂OCOCH=CH₂

A three neck flask was charged with 80.1 g of the alcohol from Example 19, 23.5 g of acrylic acid, 0.3 g of methanesulphonic acid and 0.4 g of p-methoxyphenol and this initial charge was heated to 80⁰C. The water of reaction was separated during the reaction within 24 hours at the reaction temperature and a pressure of 200 mbar. The organic phase was repeatedly washed with warm water and dried in a rotary evaporator. Conversion was verified by ¹H NMR measurements.

Examples 30 to 38: Synthesis of polyfluoroalkyl (meth)acrylates

Example 29 was repeated to convert the alcohols into polyfluoroalkyl acrylates or, with methacrylic acid, into polyfluoroalkyl (meth)acrylates. The compositions are reported in Table 4.

Table 4

Reactions to prepare polyfluoroalkyl telomeric compounds of the general composition:

R_F - A - CXY - Z (IV)

Z = COOH

Examples 19, 21-24: Z = CH₂OCOCR =CH₂; Examples 20, 25-28: Z = CON(R⁴)R⁵OCOCR⁽ Me = methyl-, Et = ethyl-, Pr = n-propyl-

Example 39: Preparation of a dispersion for textile finishing (recipe 1)

The dispersion was prepared by intensively stirring the following components in a four neck flask equipped with stirrer, reflux condenser, inert gas supply and internal thermometer:

37.5 g of polyfluoroalkyl acrylate (from Example 29)

31.O g of stearyl acrylate (SAC) 5.O g of glycidyl methacrylate (GMA) 4.5 g of hydroxyethyl methacrylate (HEMA) 30.O g of dipropylene glycol 0.4 g of dodecanethiol 6.0 g of lauryl alcohol/16 ethylene oxide adduct (nonionic surfactant A)

4.5 g of N,N-dimethyldodecylammonium acetate (cationic surfactant A) 200.0 g of water

The emulsion was heated to 60⁰C under a constant stream of nitrogen. Then, 0.2 g of the initiator 2,2'-azo-bis-isobutyronitrile (AIBN) was added. The polymerization time was 10 hours at 60⁰C.

The resulting dispersion had a solids content of about 34%. For finishing textiles, the dispersion was acidified and diluted to 30 g/1. The dispersion was applied to fibrous substrates on an HVF 59301 laboratory pad-mangle from Mathis AG (Switzerland) followed by drying and heat treatment at 160°C/30 seconds in an LTE laboratory dryer from Mathis AG (Switzerland). The commercially available textile Sahara 530306 from NEL GmbH, Neugersdorf, was used as PES/Co 65/35 substrate to compare the applications. The wet pick-up was about 66% for all examples recited. The washing/drying procedure included 5 wash cycles at 60⁰C. The corresponding pieces of fabric were made up with ballast fabric to a wash load of one kilogram. The amount of laundry detergent needed was 7 g of "Coral intensive" per wash cycle. The fabric pieces were not dried between the wash cycles. After washing, the laundry was dried in a laundry dryer.

Example 40: Preparation of a dispersion for textile finishing (recipe 2)

To prepare the dispersion, the following components were intensively stirred under an inert gas atmosphere in an autoclave equipped with a stirrer, reflux condenser and internal thermometer:

69.5 g of polyfluoroalkyl acrylate (from Example 29)

19.O g of lauryl acrylate (LA)

8.5 g of vinyl chloride (VC) 2.5 g of N-methoxymethylacrylamide (N-MAM) 3.5 g of hydroxyethyl methacrylate 30.O g of dipropylene glycol 0.5 g of dodecanethiol 7.0 g of stearyl/11 ethylene oxide adduct (nonionic surfactant B)

4.0 g of lauryltrimethylammonium chloride (cationic surfactant B) 200.0 g of water

After the emulsion had been heated to 60⁰C, 0.6 g of the initiator 2,2'-azo-bis-2- amidinopropane dihydrochloride was added. The polymerization time was 6 hours at 60⁰C. After the reaction, the excess of vinyl chloride was stripped off.

The resulting dispersion had a solids content of about 38%. For finishing of textiles, the dispersion was acidified and diluted to 30 g/1. Application to textile substrates was carried as described in Example 39.

Example 41: Preparation of a dispersion for textile finishing (recipe 3)

60.5 g of polyfluoroalkyl acrylate (from Example 29)

12.5 g of 2-ethylhexyl acrylate (2-EHAC)

15.0 g of vinylidene chloride (VDC) 3.5 g o f N-methoxymethylacrylamide

1.0 g of hydroxyethyl methacrylate

35.O g of dipropylene glycol

0.7 g of dodecanethiol

6.0 g of stearyl/11 ethylene oxide adduct (nonionic surfactant B) 5.O g of sodium dodecylsulphate (SDS)

200.0 g of water

After the emulsion had been heated to 60⁰C, 0.5 g of the initiator 2,2'-azo-bis-2- amidinopropane dihydrochloride was added. The polymerization time was 6 hours at 60⁰C. After the reaction, the excess of vinylidene chloride was stripped off.

The resulting dispersion had a solids content of about 36%. The dispersion was acidified and admixed with Cassurit HML (Clariant) and 20% by weight aqueous magnesium chloride solution, so that the concentration per 1 of liquor was in each case 30 g. Application to textile substrates was carried out as described in Example 39.

Examples 42-45: Preparation, application and testing of dispersions for textile finishing similarly to Example 39

Examples 46-49:

Preparation, application and testing of dispersions for textile finishing similarly to Example 40

Examples 50-53:

Preparation, application and testing of dispersions for textile finishing similarly to Example 41

The results of isopropanol repellency (IPA), oil repellency (oleo) and water repellency (hydro) for the dispersions from Examples 39 to 53 are reported in Table 5.

Example 54: Synthesis of C₈Fi₇(CF₂CF(CF₃)_a(CF₂CF₂)_bCF₂COOK

76.2 g (0.55 mol) of polyfluoroalkyl carboxylic acid from Example 11 were added to a dilute potassium hydroxide solution (10% by weight) and stirred at 80⁰C for 12 hours.

After concentrating by evaporation, the polyfluoroalkyl carboxylic acid potassium salt was dried by azeotropic distillation with toluene. Examples 55-57: Synthesis of polyfluoroalkyl carboxylic acid salts

Example 54 was repeated to convert the polyfluoroalkyl carboxylic acid from Example 11 into the corresponding polyfluoroalkyl carboxylic acid salts by reaction with sodium hydroxide, lithium hydroxide and ammonia.

Table 5: Preparation, application and testing of dispersions for textile finishing

Claims

1. Fluorous telomeric compounds of the formula IV:

R_F- A - CXY - Z (IV)

Z is CH₂OR³ or COO^" 1/q M^q+ or CON(R⁴)R⁵OR³

X and Y are H, Cl or F

R¹ is CF₃, OR², Cl, Br or I,

R² is perfluoromethyl, perfluoropropyl or perfluoropropyloxypropyl

R³ is H or COCR⁶=CH₂ R is H or alkyl of 1 to 6 carbon atoms

R⁵ is alkylene of 1 to 13 carbon atoms

R⁶ is H or CH₃

2. Compounds according to Claim 1, characterized in that Ri is Cl.

3. Compounds according to Claim 1, characterized in that Ri is CF₃.

4. Compounds according to Claim 1, characterized in that X and Y are F or X is F and Y is Cl or X and Y are hydrogen.

5. Compounds according to Claim 1, characterized in that a is from 0 to 5.

6. Compounds according to Claim 1, characterized in that Rp is a polyfluoroalkyl radical of 1 to 3 fluorinated carbon atoms.

7. Compounds according to Claim 1, characterized in that Rp is a polyfluoroalkyl radical of 4 to 16 fluorinated carbon atoms.

8. Compounds according to Claim 1, characterized in that the molecular weight of the compounds of the formula IV is more than 750 g/mol.

9. Compounds according to Claim 1, characterized in that a + b is > 3.

10. Copolymers containing a monomer of the formula IV, where Z is CH₂OCOCR⁶=CH₂ or CON(R⁴)R⁵OCOCR⁶=CH₂, one or more nonfluorous polymerizable vinyl monomers, one or more thermally crosslinkable or isocyanate- reactive monomers and optionally a chlorine-containing polymerizable vinyl monomer.

11. Copolymers containing, based on the total weight of the copolymer: a) 20% to 99.5% by weight and preferably 40% to 90% by weight of a monomer of the formula IV according to Claim 1, where Z is CH₂OCOCR⁶=CH₂ or CON(R⁴)R⁵OCOCR⁶=CH₂, b) 0% to 80% by weight and preferably 10% to 50% by weight of one or more nonfluorous polymerizable vinyl monomers and/or c) 0.5% to 20% by weight and preferably 1 % to 10% by weight of one or more thermally crosslinkable or isocyanate-reactive monomers.

12. Copolymers containing, based on the total weight of the copolymer: a) 40% to 99% by weight and preferably 45% to 85% by weight of a monomer of the formula IV according to Claim 1, where Z is CH₂OCOCR⁶=CH₂ or CON(R⁴)R⁵OCOCR⁶=CH₂, b) 0% to 50% by weight and preferably 0.01 % to 30% by weight of one or more nonfluorous polymerizable vinyl monomers and/or c) 0.5% to 20% by weight and preferably 1 % to 10% by weight of one or more thermally crosslinkable or isocyanate-reactive monomers and d) 0.5% to 50% by weight and preferably 2% to 30% by weight of a chlorine- containing polymerizable vinyl monomer.

13. Use of the copolymers according to Claims 10 to 12 for water-, oil- and soil- repellent finishing of fibrous substrates.