FR2697256A1 - Hydro perfluoroalkylated polyethers, process for their preparation and application to the synthesis of polyurethane materials - Google Patents

Abstract

Hydroxylated polyethers having lateral perfluoroalkylated groupings of formula (A) in which RF is a perfluorinated grouping having 1 to 20 carbon atoms, R1 is a radical capable of bearing one or more hydroxylated groupings different from the radical [ (CH2)m - C(R2R3) - ], n is an integer equal to 1, 2, 3 or 4, the identical or non-identical groupings R2 and R3 have general formula (CH2)pX wherein p = 0 or 1 and X is selected from the following groupings: hydrogen, chlorine, methyl, alkyl O, allyl ether, x is 1 - 25, y is 0 - 25, m = 1, 2 or 3. Said polyethers, precursors of fluorinated polyurethanes, can be obtained by cationic polymerization of a monomer based on perfluoroalkylated oxiranes in an inert organic solvent.

Description

HYDROXYLATED PERFLUOROALKYL POLYETHERS, PROCESS FOR
PREPARATION AND APPLICATION TO THE SYNTHESIS OF MATERIALS
Polyurethane
The present invention relates to novel hydroxylated polyethers having perfluorinated side groups, to their preparation and their use for the synthesis of materials such as fluorinated polyurethanes.

 The addition of fluorine in a polymer material leads to better surface properties, improves chemical inertness and solvent resistance and in some cases biocompatibility. Fluoropolymers used as coating materials have experienced a boom in recent years. They bring in this field exceptional properties as regards the resistance to UV radiation, the lubricating power related to a low coefficient of friction, and in relation to the reduction of the surface tension: non-wettability (hydrophobicity, oleophobia), l anti-adhesion, anti-fouling ...

 Among these materials, fluorinated polyurethanes, which have a better resistance to abrasion, are of particular interest, however, the synthesis of fluorinated polyurethanes has been limited by the availability of difunctional fluorinated molecules. The fluorinated diols marketed are in very limited numbers: hexafluoropentane diol, tetrafluorohydroquinone or 4,4 '(hexafluoro isopropylidene) diphenol.

 It should also be noted that the surface tension and the non-wettability of the fluorinated materials are not directly related to the fluorine content in the material but to the chemical structure, the positioning of the perfluorinated groups with respect to the macromolecular chain, and the length of the perfluorinated chain. With equivalent fluorine levels, a polymer having perfluorinated side groups will have a much lower surface tension than a polymer having a polyfluorinated backbone.

However, the diols mentioned above, such as those described in the literature, have major drawbacks in order to obtain polyurethanes having optimal surface properties.
or they do not comprise lateral perfluorinated groups: US Pat. Nos. 4,942,164 and US Pat.
U.S. 4,085,137,
or the group is limited to a trifluoromethyl (TM Keller, J. Polym Sci Chem Ed 23, 2557 (1985).

The diols having perfluorinated side RF links are often obtained by acid hydrolysis of fluorinated epoxides: JP Patent Nos. 01.305.045 and
DE No. 3,525,494. In this case, the alcohol functions (primary and secondary) carried by vicinal carbons have differences in reactivity. In the presence of diisocyanates, the diols of this type described in JP Nos. 02.258.821 and JP 02.258.822 or
DE No. 3,319,368 lead to rigid urethane segments that are not conducive to promoting the organization of perfluorinated groups.

 From this point of view, macrodiols, such as polyethers, containing fluorinated pendant groups, constitute a particularly attractive approach because they can lead to flexible urethane segments (flexibility of the polyether chain) and to materials with interesting surface properties ( low surface tension related to the organization of pendant perfluorinated groups).

 The α-hydroxytelechelic oligomers with fluorinated pendant groups may be obtained by grafting polyfluorinated olefins onto methylenic groups of hydroxylated polyesters: EP patent No. 0,260,842 this radical grafting necessarily leads to a random distribution of the lateral fluorinated groups, and to grafts polyfluorinated and non-perfluorinated; it is known that the presence of hydrogen atoms reduces the contribution of fluorine to the surface properties.

These perfluoroalkylated hydroxytelechelic oligomers may be obtained by polymerization of cyclic ethers such as perfluoro or polyfluoroalkyl glycidyl ethers: U.S. Patent No. 3,591,547; but the polymerization conditions described in this patent are such that the chemical structure of the oligomers formed can not be controlled. Indeed, during the cationic polymerization of cyclic ethers in the presence of acid catalysts, the priming reaction involves a nucleophilic attack of the monomeric ether (a) on the protonation-activated monomer (b). The opening of the cycle leads to the formation of a tertiary oxonium (c). The propagation reaction is carried out by successive additions of monomer molecules to the growing chain constituted by the oxonium ion (see reaction scheme 1 below). This latter approach is very attractive because of its evolutionary nature. But the polymerization reaction is disturbed by intramolecular transfer reactions in particular, which lead to cyclic compounds of low molar masses. The consequences of these parasitic reactions are an increase in the polymolecularity and the formation of nonfunctional molecules.

On the other hand, when the polymerization is carried out in the presence of hydroxyl compounds, water, alcohol,
DJ Worsfold and AM Eastham. (J. Am Chem Soc 79, 900, 1957) have hypothesized a propagating species consisting of a hydroxyl group. The mechanism explained by S. Penczek et al (Makromol Chem Makromol.

Symp. 3, 203, 1986) shows that there is competition between the nucleophilic attack of the monomer (a) on the activated cyclic ether (b) (reaction scheme 1) and the nucleophilic attack of the alcohol (d) on this same activated monomer (b) (reaction scheme 2).

 This last reaction leads to a new alcohol (e) which itself can react on a new molecule of activated monomer (b). The end of the electrically neutral growth chain (f) has a hydroxyl group which can not give rise to intra- or inter-molecular nucleophilic attack as occurs with a tertiary oxonium chain end (c) . Thus, the use of a conventional synthesis technology certainly promotes the mechanism 2, but nevertheless leads to a mixture of linear and cyclic compounds. These affect the properties of subsequent materials. The cationic polymerization of perfluoroalkyl methyl oxiranes by the known methods therefore does not make it possible to control the degree of polymerization and the functionality of the oligomers and polymers formed.

dans laquelle RF est un groupement perfluoré comportant de 1 à 20 carbones, R1 est un radical apte à porter un ou plusieurs groupements hydroxylés, n est un entier égal à 1, 2, 3 ou 4, les groupements R2 et R3 identiques ou non ont pour formule générale (CH2)pX où p = 0 ou 1 et X est sélectionné parmi les groupements suivants : hydrogène, chlore, méthyl, O alkyl, allyl éther, x est compris entre 1 et 25, y est compris entre 0 et 25, m = 1, 2 ou 3.Unexpectedly, the inventors have observed that the coupled use of a hydroxylated initiator and of particular conditions of implementation, by cationic polymerization of perfluoroalkyl oxiranes, allows the production of linear hydroxyl polyethers with pendant RF chains having; contrary to the prior art, a function perfectly known and predetermined by that of the initiator. This method makes it possible in particular to obtain aw macrodiols with side perfluoroalkyl groups, which has been shown to be of great interest for the production of polyurethane materials with low surface tensions.This route of synthesis also leads to other families of fluorinated polyethers, among which polyfluorinated macromonomers
The new hydroxylated polyfluorinated polyethers which are the subject of the present invention have the general formula

in which RF is a perfluorinated group having 1 to 20 carbons, R 1 is a radical capable of carrying one or more hydroxyl groups, n is an integer equal to 1, 2, 3 or 4, the groups R 2 and R 3, which may be identical or different, for general formula (CH 2) pX where p = 0 or 1 and X is selected from the following groups: hydrogen, chlorine, methyl, O alkyl, allyl ether, x is between 1 and 25, y is between 0 and 25, m = 1, 2 or 3.

où RF est un groupement perfluoré comportant de 1 a 12 atomes de carbone. Ces oligomères difonctionnels peuvent conduire à des matériaux fluorés par des réactions de polycondensation et en particulier à des polyuréthanes perfluoroalkylés.

The invention aims in particular at the three sub-families (1)

where RF is a perfluorinated group having from 1 to 12 carbon atoms. These difunctional oligomers can lead to fluorinated materials by polycondensation reactions and in particular to perfluoroalkylated polyurethanes.

where R1 comprises an acrylic, methacrylic or allyl polymerizable group. These macromonomers can lead to fluorinated materials by free radical or photochemical polymerization.

where p = 1 and X is an allyl ether. These difunctional oligomers which incorporate a non-fluorinated comonomer may have polymerizable groups capable of subsequently inducing crosslinking.

 The perfluoroalkylated hydroxyl polyethers according to the invention, having perfluorinated side groups, are obtained by polymerization of a monomer based on perfluoroalkyl oxiranes (homopolymerization of oxiranes and, if appropriate, copolymerization with substituted or unsubstituted non-fluorinated cyclic ethers). ) in an inert organic solvent.

According to the process of the invention
the polymerization is carried out in the presence of a monomeric or polymeric alcohol, and of an acid catalyst in such quantities that the ratio of the acid functions of said catalyst to the hydroxylated functions of said alcohol is substantially between 10 -4 and 10 -1,
- Oxirane-based monomer is added to the reaction medium continuously or semi-continuously, so that the rate of addition of said monomer is less than or equal to the rate of consumption of the perfluoroalkylated oxirane.

 By "oxirane-based monomer" is meant both a perfluoroalkylated oxirane used alone and in admixture with other cyclic ethers.

 The alcohol used may be a mono-alcohol or a polyol, monomer or polymer; the acid catalyst is used in low concentration in a ratio to the hydroxyl functional groups, preferably between 2.10-4 and 10-2. The monomer may consist of one or more polyfluorinated oxiranes or of a polyfluorinated oxirane mixture / nonfluorinated cyclic ether (in particular 3, 4 or 5 atom rings) in order to homopolymerize oxiranes, with, if appropriate, a copolymerization with said cyclic ether (s).

 In particular, the non-fluorinated cyclic ether may be tetrahydrofuran, an oxetane such as 3,3-dimethyl oxetane or an allyl oxirane such as glycidyl allyl ether.

 In a first step, the reaction medium is produced by mixing in the solvent, the alcohol, the monomer based on oxiranes in an amount at most equal to the stoichiometry with respect to the hydroxyl functions of said alcohol, and the acid catalyst.

 The addition of said monomer takes place slowly and the duration of addition is in particular between 1 and 60 hours depending on the nature of the alcohol used as initiator and the degree of polymerization of the desired polyfluorinated polyether. The addition rate of the monomer is advantageously chosen to be close to half the consumption rate of the perfluoroalkylated oxirane (by "close to" is meant an addition rate differing by at most 20% from the speed of consumption).

 Thus, the concentration of hydroxyl functions present in the reaction medium remains throughout the duration of the reaction greater than the concentration of polyfluorinated oxirane, and preferably close to twice the latter.

The polymerization reaction is preferably carried out in the inert organic solvent at a temperature between 200C and 800C. In particular, chlorinated hydrocarbon solvents such as CH 2 Cl 2, CHCl 3,
CCl4, CCl3CH3 or CH2ClCH2Cl are suitable for the reaction and can be used as pure product or as a mixture. The cationic polymerization of the fluorinated oxiranes according to this process is carried out with a degree of conversion greater than 95%.

 The acid catalyst used in the process of the invention is preferably a superacid catalyst having a Hammet acidity function of less than -6 ("acid catalyst" means a single compound or a mixture of compounds); it may be chosen from those known in the art, including Lewis acids and Bronsted acids, and more particularly from the following group: BF3 [(C2H5) 2O], HBF4 (C2H5) 2O], CF3SO3H.

The following alcohols are suitable for carrying out the synthesis of hydroxylated fluorinated polyethers, but they are not an exhaustive list
1 octanol, 1 octadecanol, allyl alcohol, 1 hydroxy 1, 1, 2, 2 tetrahydro perfluoro octane, hydroxy ethyl acrylate, hydroxy ethyl methacrylate, hydroxy propyl acrylate, hydroxy propyl methacrylate, 1,6 hexanediol, ethylene glycol, diethylene glycol, 1 , 4 butanediol, dimethylol propane, glycerol, 1,1,1 trimethylol propane.

Monoalcohols and polymeric polyols can also be used
polyethylene glycol methyl ether, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, ethoxylated bisphenol A, polybutadiene hydroxy telechelic ethoxylated glycerol, hydroxytelechelic polyester. These polymers are in particular chosen from molar masses of between 250 and 3500 g / mol-1.

According to the chemical structure of the alcohol which acts as an initiator, various types of perfluoroalkylated polyethers have been obtained - perfluoroalkylated macrodiols homopolymers with, as alcohol, a monomeric diol, polyurethane precursors,
perfluoroalkylated hydroxylated macromonomers using a monomeric alcohol having a polymerizable function,
tri-sequenced perfluoroalkyl macrodiols, incorporating a polymeric diol,
perfluoroalkylated polyols with, as alcohol, a triol or a tetrol,
monohydroxylated perfluoroalkyl homopolymers in the presence of a monomeric monoalcohol,
monohydroxylated diblock copolymers in the presence of a polymeric monoalcohol.

 For each of these types of hydroxylated polyfluorinated polyethers, it is possible to incorporate in the polymer chain non-fluorinated cyclic ethers, in particular with 3, 4 or 5 atoms, which include but are not limited to epichlorohydrin, 3, 3-dimethyl oxetane, tetrahydrofuran, glycidyl allyl ether, so as to obtain randomly linked hydroxy-perfluoroalkylated copolymers.

 The fluorinated polyethers according to the present invention are essentially linear and possess one or more reactive hydroxyl functional groups at the end of chains. The functionality of these fluorinated polyethers is determined by the number of OH functions contained in the alcohol molecule introduced at the beginning of the reaction. The alcohol that plays the role of initiator is consumed at the very beginning of the reaction and totally integrated in the polyether chain. The hydroxyl functions formed at the end of the chain during the homopolymerization of the fluorinated oxiranes are almost exclusively secondary. The degree of polymerization of the perfluoroalkylated polyethers, determined by 1H NMR, is controlled by the ratio of the monomer concentrations based on oxiranes and on the alcohol used as an initiator. The average molecular weight of the perfluoroalkylated polyethers, limited by their solubility in the reaction medium The level of fluorine, incorporated as perfluoroalkyl side groups, is between 10 and 70% and in particular between 25 and 67%. The hydroxyl number of said perfluoroalkyl polyethers is between 20 and 200.

Their glass transition temperature or melting temperature can vary between -800 C and +1000 C depending on the number of fluorinated oxirane units introduced into the polymer chain, the length of the perfluorinated group RF and the nature of the alcohol used as initiator. When the perfluorinated groups RF comprise 8 or more carbons, the perfluoroalkylated polyethers may have a crystalline structure.

Hydroxylated polyethers having perfluoroalkyl pendant groups obtained by the process previously described, are capable of reacting with organic compounds having two isocyanate groups to give linear prepolymers terminated by isocyanate functional groups. Among the organic diisocyanates which can be used for the synthesis of these prepolymers, mention may be made of
hexamethylene diisocyanate, isophorone diisocyanate, toluene diisocyanate, 4,4'-diphenyl methane diisocyanate, trimethyl hexamethylene diisocyanate, and the like.

 In a second step, the obtained perfluoroalkylated α-diisocyanate prepolymers are polymerized in the presence of a crosslinking agent and / or a chain extender, with or without the addition of catalyst to give fluorinated polyurethanes. The polyols and polyamines are suitable as chain extenders or crosslinking agents, in particular aliphatic diols or triols (2,2-dimethylpropane 1,3-diol; 2,2-diethylpropane-1,3-diol; 2-ethyl-2-hydroxymethyl-propane-1,3-diol). ) or the polyesters glycols; or polyether glycols (polyethylene, polypropylene, polytetramethylene), or aliphatic or aromatic diamines.

 The perfluoroalkyl polyurethanes obtained from the polyethers of the present invention have remarkable surface properties. The surface tensions of these fluorinated polyurethanes are very low, of the order of 15 nm / m.sup.-1 and even lower depending on the nature of the pendant perfluorinated groups. These surface tensions, lower than those of perfluorinated polymer materials, give the coatings that can be made from these polyfluorinated polyurethanes, excellent hydrophobic and oleophobic properties. These polyurethane coatings can be applied to different types of surface: metals, silica, synthetic or natural organic materials ...

 The following examples, which are not limiting, illustrate in greater detail the invention and show the diversity of the compounds obtainable by this process.

General experimental conditions for the production of perfluoroalkyl polythers
The reaction solvents, free from stabilizers, are dried in the presence of calcium hydride, calcium chloride or sodium sulfate. The alcohols used as initiators are dried on molecular sieves.

The fluorinated oxiranes are purified on a silica column.

 The polymerization is carried out under a nitrogen atmosphere. The nitrogen used to purge the reaction medium is dried on molecular sieve and silica gel columns before use.

 In a three-necked flask equipped with a nitrogen scavenging system, the alcohol (polymerization initiator), the solvent or the mixture of solvents and a volume (V) of fluorinated oxirane solution or of the fluorinated oxirane mixture are introduced. comonomer representing a quantity of monomer (s) stoichiometric with respect to hydroxyl functions.

 The amount of acid catalyst injected and the reaction temperature depend on the nature of the initiator. The monitoring of the polymerization, by steric exclusion chromatography (SEC), makes it possible: to follow the disappearance of the initiator at the beginning of the reaction and to determine the time (t) necessary for the consumption of the initial fraction of monomer (s) ) contained in the volume (V). The solution containing the monomer (s) is then introduced into the reaction medium continuously using a syringe pump with a flow rate equal to V / 2.t.

 The perfluoroalkylated hydroxylated polyethers are analyzed by 1 H and 19 F NMR, size exclusion chromatography and differential scanning calorimetry (DSC).

 The molar masses and the functionality (Fn) of the fluorinated polyethers are determined by 1 H NMR, based on the proton resonance of the hydroxyl chain ends (- CH - OH) after modification to trifluoroacetic ester or phenyl carbamate. The theoretical molar masses are calculated from the ratio [monomer (s)] / [hydroxylated initiator]. The molar masses Mw and Mn as well as the polymolecularity (I) are evaluated by steric exclusion chromatography, in polyethylene glycol equivalents, when the fluorinated polyethers are soluble in tetrahydrofuran, eluting from the chromatography.

Aeneral experimental conditions for the
Preparation of perfluoroalkylated polyurethanes from the above-mentioned polyethers
The preparation of perfluoroalkylated polyurethanes comprises two steps.

 At first a prepolymer has a; The diisocyanate is prepared by reacting a perfluoroalkylated macrodiol described in the present patent with a diisocyanate in the presence of a catalyst. The reaction is carried out under a nitrogen atmosphere under conditions similar to those described above.

 In a three-necked flask equipped with a condenser, a septum and a device allowing a nitrogen sweep, introducing the perfluoroalkyl macrodiol in solution and the catalyst (tin dibutyl dilaurate) in a ratio [catalyst] / [diol] from 10-2 to 5.10-2. An amount of diisocyanate is then injected into the reaction medium, such that the ratio [isocyanate functional groups] / [hydroxyl functional groups] is equal to 2.

 The reaction, followed by IR spectroscopy, is considered complete when the ratio of the intensities of the absorption bands of the isocyanate groups to 2260 cm 1 and carbamates at 1720 cm 1 remains constant. After evaporation of the reaction solvent, the isocyanate functions of the prepolymer are determined by return in the presence of n-dibutylamine.

 In a second step, the diisocyanate prepolymer in solution is reacted with a chain extender diol and / or a crosslinking agent in such a proportion that the stoichiometry between the isocyanate and hydroxyl functional groups is observed.

Examples of perfluoroalkylated macrodiols
Preparation of polyperfluorobutyl methyl oxiranes hydroxylated aws
Example 1
Depending on the degree of polymerization desired, from 0.72 g to 1.44 g (2.25 mmol to 4.5 mmol) of ethoxylated bisphenol A of average mass Mn = 320 g mol -1, in solution in dichloromethane (0.15 mol.l-1) are introduced by a septum into the reaction flask, maintained under a nitrogen atmosphere. The amount of HBF4 etherate, catalyst of the reaction, required for a ratio [catalyst] / [diol] equal to 5 × 10 -3 is injected into the reaction medium.

 Perfluorobutyl methyl oxirane (10 g, 36.2 mmol) is dissolved in dichloromethane (1.8 mol.l-1). A fraction of this solution, such that the ratio [fluorinated monomer] / [diol] is equal to 2 is injected into the reaction medium maintained with magnetic stirring. The remainder of the fluorinated oxirane solution is then added continuously at a rate corresponding to 0.25 moles of fluorinated oxirane per hour and per mole of diol.

The duration of addition of the fluorinated monomer varies from 20 hours for a theoretical degree of polymerization (DPth) equal to 8, up to 46 hours for a DPth = 16.

The polymerization is carried out at room temperature. The reaction medium is deactivated with a solution of ammonia in tetrahydrofuran when the fluorinated oxirane is no longer detected by size exclusion chromatography. The reaction solvent is evaporated under reduced pressure.

<Tb>

<SEP> DPth <SEP> = <SEP> 8 <SEP> DPth <SEP> = <SEP> 16
<tb> Mass <SEP> theoretical <SEP> 2 <SEP> 530 <SEP> 4 <SEP> 740
<tb> Mn <SEP> (NMR <SEP> 1H) <SEP> 2 <SEP> 420 <SEP> 4 <SEP> 630
<tb> Mn <SEP> (SEP) <SEP> 1 <SEP> 620 <SEP> 1 <SEP> 950
<tb> Mw <SEP> (SEC) <SEP> 1 <SEP> 810 <SEP> 2 <SEP> 300
<tb> Polymolecularity <SEP> I <SEP> 1.12 <SEP> 1.18
<tb> Functionality <SEP> Fn <SEP> 2.0 <SEP> 2.1
<tb> 54.0 <SEP> 57.7
<tb> TgOC <SEP> -37 <SEP> -37
<Tb>
Example 2
The diol used in Example 1 is substituted with diethylene glycol (0.48 g, 4.5 mmol). The ratio [HBF4 etherate] / [diol] is equal to 2.10-. The fluorinated oxirane solution is added at a rate of 0.34 moles of fluorinated monomer per hour and per mole of diol. For a theoretical degree of polymerization equal to 8, the addition time is 18 hours. All the experimental conditions are analogous to those described in Example 1.

<Tb>

Mass <SEP> theoretical <SEP> 2 <SEP> 310
<tb> Mn <SEP> (NMR <SEP> 1H) <SEP> 2 <SEP> 400
<tb> Mn <SEP> (SEC) <SEP> 1 <SEP> 810
<tb> Mw <SEP> (SEC) <SEP> 2 <SEP> 020
<tb> Polymolecularity <SEP> I <SEP> 1,11
<tb> Functionality <SEP> Fn <SEP> 1.8
<tb> 59.1 <SEP>
<tb> TgOC <SEP> -51
<Tb>
Example 3
The polymerization initiator is 3 allyloxy 1,2 propanediol, the polymerization conditions have been modified on the following points
3-allyloxy 1,2-propanediol is in solution in 1,2-dichloroethane (0.45 mol.l-1),
the ratio [HBF4 etherate] / [3 allyloxy 1,2-propanediol] is equal to 2.6 × 10 -3,
the reaction temperature is 550 ° C.
the fluorinated oxirane is added with a flow rate of 1 mole per hour and per mole of diol,
the addition time is between 6 hours and 14 hours for DPth respectively of 8 and 16.

<Tb>

<SEP> DPth <SEP> = <SEP> 8 <SEP> DPth <SEP> = <SEP> 16
<tb> Mass <SEP> theoretical <SEP> 2 <SEP> 340 <SEP> 4 <SEP> 550
<tb> Mn <SEP> (NMR <SEP> 1H) <SEP> 2 <SEP> 450 <SEP> 4 <SEP> 350
<tb> Mn <SEP> (SEC)
<tb> Mw <SEP> (SEP) <SEP> 1 <SEP> 825 <SEP> 1 <SEP> 740
<tb> Polymolecularity <SEP> I <SEP> 1.1 <SEP> 1.07
<tb> Functionality <SEP> Fn <SEP> 2,2 <SEP> 2,3
<tb> 58.6 <SEP> 60.1
<tb> TgOC <SEP> -48 <SEP> -48.5
<Tb>
Preparation of polyperfluorohexyl methyl oxiranes hydroxylated aws
Example 4
The experimental conditions comparable to those described in example i differ on the following points
according to the degree of polymerization chosen, a weight of between 0.53 g and 1.06 g of ethoxylated bisphenol A of average weight Mn = 320 g mol.l -1 (1.66 mmol to 3.32 mmol); dissolved in a mixture of dichloromethane1,1,1 trichloroethane in a volume ratio of 3/1 is added,
perfluorohexyl methyl oxirane (10 g, 26.6 mmol) is in solution in 1,1,1-trichloroethane,
after addition of the first fraction of the fluorinated oxirane solution corresponding to twice the amount of diol, the fluorinated monomer solution is injected at a rate of 1.5 mol per hour and per mol of diol,
the duration of addition of the fluorinated oxirane is between 4 hours and 10 hours for DPths of 8 and 16.

<SEP> DPth <SEP> = <SEP> 8 <SEP> DPth <SEP> = <SEP> 16
<tb> Mass <SEP> theoretical <SEP> 3 <SEP> 330 <SEP> 6 <SEP> 340
<tb> Mn <SEP> (NMR <SEP> 1H) <SEP> 3 <SEP> 180 <SEP> 6 <SEP> 710
<tb> Mn <SEP> (SEC) <SEP> 1 <SEP> 810 <SEP> 2 <SEP> 050
<tb> Mw <SEP> (SEC) <SEP> 2 <SEP> 030 <SEP> 2 <SEP> 210
<tb> Polymolecularity <SEP> I <SEP> 1.12 <SEP> 1.1
<tb> Functionality <SEP> Fn <SEP> 1.9 <SEP> 2.0
<tb><SEP> F <SEP> 59.1 <SEP> 62.6
<tb> Tq C <SEP> -30 <SEP> -31
<Tb>

Example 5
The experimental conditions are comparable to those described in Example 4 except the following points
diol (1.4 g, 3.32 mmol), a bisphenol
A ethoxylated medium weight 420 g per mole, is in solution in a mixture of dichloromethane - 1,1,1 trichloroethane in a ratio by volume 1/3,
the fluorinated oxirane (26.6 mmol) is added with a flow rate of 0.5 mole per hour and per mole of diol,
the duration of addition of the fluorinated monomer is 12 hours for a theoretical degree of polymerization of 8.

<Tb>

Theoretical <SEP> mass <SEP> 3 <SEP> 430
<tb> Mn <SEP> (NMR <SEP> 1H) <SEP> 3 <SEP> 360
<tb> Mn <SEP> (SEC) <SEP> 2 <SEP> 145
<tb> Mw <SEP> (SEC) <SEP> 2 <SEP> 510
<tb> Polymolecularity <SEP> I <SEP> 1.17
<tb> Functionality <SEP> Fn <SEP> 2.0
<tb> 57.4 <SEP>
<tb> Tq C <SEP> -34
<Tb>
Example 6
Under experimental conditions comparable to those described in Example 5, the HBF4 etherate catalyst is substituted with BF3 etherate, in a ratio [BF3 etherate] / tdiol] equal to 10-1.

The fluorinated oxirane (26.6 mmol) is added at a rate of 0.6 mole per hour and per mole of diol. The duration of addition of the fluorinated oxirane is 10 hours for a DPth equal to 8.

<Tb>

Theoretical <SEP> mass <SEP> 3 <SEP> 430
<tb> Mn <SEP> (NMR <SEP> 1H) <SEP> 3 <SEP> 540
<tb> Mn <SEP> (SEC) <SEP> 2 <SEP> 230
<tb> Mw <SEP> (SEC) <SEP> 2 <SEP> 540
<tb> Polymolecularity <SEP> I <SEP> 1.14
<tb> Functionality <SEP> Fn <SEP> 2.1
<tb> 57.4 <SEP>
<tb> TgOC <SEP> -37
<Tb>
Example 7
Experimental conditions similar to those described in Example 2 differ on the following points
the diol used is ethylene glycol (0.35 g, 3.32 mmol) in solution in a dichloromethane / 1,1,1-trichloroethane mixture in a volume ratio of 1: 4,
perfluorobutyl methyl oxirane is substituted by perfluorohexyl methyl oxirane (10 g, 26.6 mmol) in solution in 1,1,1-trichloroethane,
the HBF4 etherate catalyst is substituted with CF3SO3H in a ratio [CF3SO3H] / [diol] equal to 2.10-2
The fluorinated oxirane is added with a flow rate of 1.1 moles per hour and per mole of diol. The duration of addition of the oxirane is 5.5 hours for a DPth equal to 8.

<Tb>

Mass <SEP> Theoretical <SEP> 3 <SEP> 120
<tb> Mn <SEP> (NMR <SEP> 1H) <SEP> 3 <SEP> 280
<tb> Mn <SEP> (SEC) <SEP> 2 <SEP> 210
<tb> Mw <SEP> (SEC) <SEP> 2 <SEP> 530
<tb> Polymolecularity <SEP> I <SEP> 1.15
<tb> Functionality <SEP> Fn <SEP> 2.1
<tb>% <SEP> F <SEP> 63.3 <SEP>
<tb> Tg C <SEP> -35
<Tb>
Example 8 and 9
Compared to Example 4, the ethoxylated bisphenol A was substituted with 1,6 hexanediol (Example 8) and 1,4 dimethanol cyclohexane (Example 9) (3.32 mmol), dissolved in 1.2 dichloro ethane.

The perfluorohexyl methyl oxirane solution is added with a flow rate of 1 mole per hour and per mole of 1,6 hexanediol and 3 moles per hour and per mole of 1,4 dimethanol cyclohexane. The addition times are respectively 6 hours and 2 hours. The temperature of the reaction medium is maintained at 55 C.

<Tb>

<SEP> Example <SEP> 8 <SEP> Example <SEP> 9
<tb> Mass <SEP> theoretical <SEP> 3 <SEP> 130 <SEP> 3 <SEP> 150
<tb> Mn <SEP> (NMR <SEP> 1H) <SEP> 3 <SEP> 200 <SEP> 2 <SEP> 400
<tb> Mn <SEP> (SEC)
<tb> Mw <SEP> (SEP) <SEP> 1 <SEP> 810 <SEP> 1 <SEP> 880
<tb> Polymolecularity <SEP> I <SEP> 1.12 <SEP> 1.18
<tb> Functionality <SEP> Fn <SEP> 1.19 <SEP> 2.0
<tb> 63.3 <SEP> 61.8
<tb> TgOC <SEP> -44 <SEP> -49
<Tb>
Example 10
The conditions described in Example 4 are modified on the following points
the diol is a hydroxytelechelic polytetrahydrofuran (0.10 g, 0.41 mmol) of mass Mn = 250,
the reaction solvent is 1,1,1-trichloroethane,
the ratio [HBF4 etherate] / [diol] is equal to 1.5 10 -2,
the addition time of the fluorinated oxirane is 37 hours for a DPth = 25.

<Tb>

Mass <SEP> theoretical <SEP> 9 <SEP> 650
<tb> Mn <SEP> (NMR <SEP> 1H) <SEP> 9 <SEP> 530
<tb> Mn <SEP> (SEC) <SEP> 1 <SEP> 630
<tb> Mw <SEP> (SEC) <SEP> 2 <SEP> 040
<tb> Polymolecularity <SEP> I <SEP> 1.25
<tb> Functionality <SEP> Fn <SEP> 2.1
<tb> 64.3 <SEP>
<tb> TgOC <SEP> -41
<Tb>
Preparation of Polyperfluorooctyl Methyl Oxiranes Hydroxylated
Example 11
Under the conditions described in Example 1, the following data concerning
the initiator: the amount of ethoxylated bisphenol A (Mn = 320 g mol) used varies according to the desired degree of polymerization from 0.42 g to 0.84 g (from 1.31 mmol to 2.62 mmol). )
the monomer: perfluorooctyl methyl oxirane (10 g, 21 mmol) is in solution (1 mol.l-1) in 1,1,1-trichloroethane,
the addition of the monomer: the flow rate is 1 mole per hour and per mole of diol,
the duration of the polymerization: it varies from 6 hours for a DPth equal to 8 at 14 hours for a DPth equal to 16.

<Tb>

<SEP> DPth <SEP> = <SEP> 8 <SEP> DPth <SEP> = <SEP> 16
<tb> Mass <SEP> theoretical <SEP> 4 <SEP> 130 <SEP> 7 <SEP> 940
<tb> Mn <SEP> (NMR <SEP> 1H) <SEP> 4 <SEP> 220 <SEP> 8 <SEP> 220
<tb> Functionality <SEP> Fn <SEP> 2.2 <SEP> 2.1
<tb> 62.7 <SEP> 65.2
<tb> TfOC <SEP> * <SEP> 30 <SEP> 66
<Tb>
* : Melting temperature
Example 12
This procedure follows the conditions defined in Examples 1 and 10 except the following points
3 allyloxy 1,2 propanediol (1.3 mmol.

to 2.6 mmol.) according to the desired degree of polymerization, in solution in 1,2-dichloroethane (0.5 mol.l -1) is substituted for the ethoxylated bisphenol A,
perfluorooctyl methyl oxirane is added at a rate of 1.4 moles per hour and per mole of 3 allyloxy 1,2 propanediol,
the addition time of the fluorinated oxirane is between 90 minutes and 4 hours for DPth respectively of 4 and 8,
the temperature of the reaction medium is maintained at 55 ° C.

<Tb>

<SEP> DPth <SEP> = <SEP> 8 <SEP> DPth <SEP> = <SEP> 16
<tb> Mass <SEP> Theoretical <SEP> 3 <SEP> 940 <SEP> 7 <SEP> 750
<tb> Mn <SEP> (NMR <SEP> 1H) <SEP> 4 <SEP> 050 <SEP> 7 <SEP> 460
<tb> Functionality <SEP> Fn <SEP> 2.1 <SEP> 2.0 <SEP>
<tb> 65.9 <SEP> 66.7
<tb> Tf0C <SEP> 61.4 <SEP> 81.3
<Tb>
Synthesis of hydroxylated perfluoroalkylated macromonomers
Example 13
Polymerization of perfluorobutyl methyl oxirane (10 g) initiated with hydroxyethyl methacrylate (0.58 g, 4.5 mmol) was carried out under conditions similar to those described in Example 1. A fraction of the solution of fluorinated oxirane in dichloromethane, such that the ratio [fluorinated oxirane] / [alcohol] is equal to 1 is first injected into the reaction medium. The remainder of the fluorinated oxirane solution is then added at a rate of 0.57 moles per hour and per mole of hydroxyethyl methacrylate. The monomer addition time is 12 hours for a DPth = 8

<tb> Mass <SEP> theoretical <SEP> 2 <SEP> 340
<tb> Mn <SEP> (NMR <SEP> 1H) <SEP> 2 <SEP> 255
<tb> Mn <SEP> (SEC) <SEP> 1 <SEP> 520
<tb> Mw <SEP> (SEC) <SEP> 1 <SEP> 710
<tb> Polymolecularity <SEP> I <SEP> 1,1
<tb> Functionality <SEP> Fn <SEP> 1,1
<tb>% <SEP> F <SEP> 58.4 <SEP>
<Tb>
Example 14
With respect to the conditions described in Examples 1 and 13, perfluorohexyl methyl oxirane (10 g, 26.6 mmol) is used as the monomer in place of perfluorobutyl methyl oxirane and as the initiator hydroxyethyl methacrylate (0.43 g , 3.32 mmol.) For a DPth = 8, the addition time of the monomer in solution in 1,1,1 triochloroethane (reaction solvent) is 4.5 hours with a flow rate of 1.5 mole of fluorinated oxirane per hour and per mole of hydroxyethyl methacrylate.

<Tb>

Mass <SEP> theoretical <SEP> 3 <SEP> 140
<tb> Mn <SEP> (NMR <SEP> 1H) <SEP> 3 <SEP> 360
<tb> Mn <SEP> (SEC) <SEP> 1 <SEP> 750
<tb> Mw <SEP> (SEC) <SEP> 2 <SEP> 020
<tb> Polymolecularity <SEP> I <SEP> 1.16
<tb> Functionality <SEP> Fn <SEP> 1,2
<tb> 63.1 <SEP>
<tb> TgOC <SEP> -52
<Tb>
Example 15
The polymerization is carried out under the same conditions as those described in Example 14, the hydroxyethyl methacrylate being substituted with allyl alcohol. The addition of the perfluorohexyl methyl oxirane in solution in 1,1,1-trichloroethane is carried out with a flow rate of 1 mole per hour and per mole of allyl alcohol, ie an addition time of 7 hours for one hour.
DPth = 8.

<Tb>

Mass <SEP> Theoretical <SEP> 3 <SEP> 070
<tb> Mn <SEP> (NMR <SEP> 1H) <SEP> 3 <SEP> 190
<tb> Mn <SEP> (SEC) <SEP> 1 <SEP> 600
<tb> Mw <SEP> (SEC) <SEP> 1 <SEP> 860
<tb> Polymolecularity <SEP> I <SEP> 1.16
<tb> Functionality <SEP> Fn <SEP> 1,2
<tb> 64.8 <SEP>
<tb> TgOC <SEP> -45
<Tb>
Synthesis of perfluoroalkylated macrodiols
Example 16
Experimental conditions similar to those described in Examples 1 and 4 have been modified with regard to
the diol is used a polybutadiene hydroxytelechelic mass 3,200 (3.32 mmol) in solution in 1,1,1 trichloroethane,
the ratio [HBF4 etherate] / [diol] is equal to 8.5 10-3 "
the duration of addition of the monomer is 30 hours for a DPth of 8, with a flow rate of 0.2 mole of fluorinated oxirane per hour and per mole of diol.

<Tb>

Mass <SEP> Theoretical <SEP> 6 <SEP> 370
<tb> Mn <SEP> (NMR <SEP> 1H) <SEP> 6 <SEP> 460
<tb> Functionality <SEP> Fn <SEP> 2.0
<tb> 33.5 <SEP>
<tb> Tg C <SEP> 5
<Tb>
Synthesis of monohydroxy perfluoroalkyl homopolymers
Example 17
The polymerization of perfluorohexyl methyl oxirane (20 g, 53.2 mmol) in solution in 1,1,1-trichloroethane and initiated with perfluorobutyl 2 ethanol (7 g, 26.5 mmol) is carried out according to the conditions described. in Examples 1 and 13. For a DPth = 2, the duration of addition of the monomer is 2 hours, at a rate of 0.25 mole per hour and per mole of fluorinated alcohol.

<Tb>

Mass <SEP> Theoretical <SEP> 1 <SEP> 020
<tb> Mn <SEP> (NMR <SEP> 1H) <SEP> 940
<tb> Mn <SEP> (SEC) <SEP> 1 <SEP> 010
<tb> Mw <SEP> (SEC) <SEP> 1 <SEP> 210
<tb> Polymolecularity <SEP> I <SEP> 1.19
<tb> Functionality <SEP> Fn <SEP> 1.0
<tb> 47.3 <SEP>
<tb> TgOC <SEP> -69.5
<Tb>
Synthesis of hydroxylated perfluoroalkylated random copolymers
Example 18
Perfluorohexyl methyl oxirane (26.6 mmol) in solution in 1,1,1-trichloroethane (9 ml) is copolymerized with tetrahydrofuran (53.2 mmol) according to the conditions already described (Example 1). The diol used as initiator is ethoxylated bisphenol A (3.32 mmol) in solution in dichloromethane. The secondary alcohol functions, evidenced by 1 H NMR, indicate the presence of fluorinated units at the end of the chain. The addition of the monomers, in a ratio [fluorinated oxirane] / [tetrahydrofuran] = 1/2, is carried out at a rate of 1 mole per hour and per mole of diol. The duration of addition of the monomers is 25 hours.

<Tb>

Theoretical <SEP> mass <SEP> 4 <SEP> 480
<tb> Mn <SEP> (NMR <SEP> 1H) <SEP> 4 <SEP> 260
<tb> Mn <SEP> (SEC) <SEP> 1 <SEP> 790
<tb> Mw <SEP> (SEC) <SEP> 2 <SEP> 210
<tb> Polymolecularity <SEP> I <SEP> 1.23
<tb> Functionality <SEP> Fn <SEP> 2,2
<tb> 49.2 <SEP>
<tb> TgOC <SEP> -49
<Tb>
EXAMPLE 19
As in Example 18, perfluorohexyl methyl oxirane (5 g, 13.3 mmol) is copolymerized with a nonfluorinated cyclic ether, in this case allyl glycidyl ether (0.76 g, 6.6 mmol). . The monomers, in a ratio of fluorinated toxirane / [allyl glycidyl ether] = 2/1, are in solution in 1,1,1-trichloroethane. The ethoxylated bisphenol A (2.22 mmol) is in solution (0.13 mol.l-1) in a mixture CH2Cl2 / CH3CCl3 = 70 / 30.The ratio [HBF4 etherate] / [diol] is equal to 10- 2. The duration of addition of the monomers is 8.5 hours with a flow rate of 1 mole per hour and per mole of diol.

<Tb>

Mass <SEP> Theoretical <SEP> 2 <SEP> 920
<tb> Mn <SEP> (NMR <SEP> 1H) <SEP> 3 <SEP> 180
<tb> Mn <SEP> (SEC) <SEP> 1 <SEP> 400
<tb> Mw <SEP> (SEC) <SEP> 1 <SEP> 570
<tb> Polymolecularity <SEP> I <SEP> 1.12
<tb> Functionality <SEP> Fn <SEP> 2.0
<tb> 51.3 <SEP>
<tb> TgOC <SEP> -70
<Tb>
EXAMPLE 20
In a first step, a diisocyanate prepolymer is prepared. A mixture of perfluoroalkylated macrodiol (10 g) having a DPth equal to 16, prepared according to the conditions described in Example 1, in solution in 1,1,1-trichloroethane (0.1 ml-1) and dibutyl dilaurate. tin (23 mg) is introduced into the reaction flask maintained under a nitrogen atmosphere. The isophorone diisocyanate (1.03 g) is then injected by the septum into the reaction medium, maintained under magnetic stirring. The reaction is carried out at 450 ° C. The reaction time is 12 hours. The reaction solvent is evaporated under reduced pressure.

 In a second step, the previously obtained diisocyanate prepolymer dissolved in THF is reacted with 2-ethyl-2-hydroxy-methyl-1,3-propanediol in such a quantity that the stoichiometry between the hydroxy and isocyanate functions is generally respected.

 The fluorinated polyurethane films deposited on a glass support are annealed at 1200 ° C. for 6 hours. The disappearance of the isocyanate functions is verified by IR spectroscopy. The critical surface tension of the fluorinated coating is 15 mN.m.sup.-1.

EXAMPLE 21
Under conditions comparable to those described in Example 20, the isophorone diisocyanate (1.3 g) is added to a mixture of perfluoroalkylated macrodiol (10 g) of DPth equal to 8, prepared according to the conditions described in the example. 7 and dibutyl tin dilaurate (31 mg).

 The prepolymer has a; The diisocyanate thus obtained after reaction with 2-ethyl-2-hydroxy-methyl-1,3-propanediol gives a fluorinated polyurethane whose critical surface tension is 12.4 mN.m.sup.-1.

Example 22
The experimental conditions used differ from those described in Example 20 on the following points
the macrodiol used (10 g) of DPth equal to 8 was prepared according to the conditions described in Example 11,
the macrodiol is in solution in 1,1,1-trichloroethane (0.1 Ml-1),
the reaction with isophorone diisocyanate (1.24 g) is catalyzed by tin dibutyl dilaurate (26 mg),
in the second stage of the preparation, the prepolymer aw diisocyanate is reacted with an equimolecular mixture of 2 ethyl 2-hydroxy-methyl-1,3-propanediol and 2,2-dimethyl-1,3-propanediol.

 The critical surface tension of the polyurethane thus obtained is 9.4 mN.m.sup.-1.

Claims (22)

 1 / - Homopolymeric hydroxylated polyether or randomly linked copolymer having perfluoroalkylated side groups of formula

 in which RF is a perfluorinated group having 1 to 20 carbons, R 1 is a radical capable of carrying one or more hydroxyl groups, n is an integer equal to 1, 2, 3 or 4, the groups R 2 and R 3, which may be identical or different, for general formula (CH 2) pX where p = O or 1 and X is selected from the following groups: hydrogen, chlorine, methyl, O alkyl, allyl ether, x is from 1 to 25, y is from 0 to 25, m = 1, 2 or 3.  2 / - Hydro perfluoroalkylated polyether according to claim 1, wherein y = 0, n = 2 and RF is a perfluorinated group having from 1 to 12 carbon atoms.  3 / - hydroxylated perfluoroalkylated polyether according to claim 1, wherein y = 0, n = 1 and R1 comprises an acrylic, methacrylic or allyl polymerizable group.  4 / - Hydro perfluoroalkylated polyether according to claim 1, wherein m = 1, R2 = H and R3 is a CH2X group where X is an allyl ether.  5 / - Process for the preparation of a hydroxylated polyether according to claim 1, having perfluoroalkylated side groups, said process consisting in carrying out a cationic polymerization of a monomer based on perfluoroalkyl oxiranes in an inert organic solvent and being characterized in what  the polymerization is carried out in the presence of a monomeric or copolymer alcohol, and of an acidic catalyst in such quantities that the ratio of the acid functions of said catalyst to the hydroxylated functions of said alcohol is substantially between 10 -4 and 10 -1,  - Oxirane-based monomer is added to the reaction medium continuously or semi-continuously, so that the rate of addition of said monomer is less than or equal to the consumption rate of the alkylated perfluorinated oxirane.  6 / - Preparation process according to claim 5, characterized in that the monomer based on oxiranes is a mixture of perfluoroalkyl oxiranes and at least one non-fluorinated cyclic ether, in particular rings with 3, 4 or 5 atoms in order to carry out a copolymerization of said oxiranes with said cyclic ether (s).  7 / - The method of claim 6, wherein the perfluoroalkyl oxirane is copolymerized with tetrahydrofuran, an oxetane such as dimethyl 3,3-oxetane or an allyl oxirane such as glycidyl allyl ether.  8 / - Preparation process according to one of claims 5, 6 or 7 wherein  initially, the reaction medium is produced by mixing in the solvent, the alcohol, the monomer based on oxiranes in an amount at most equal to the stoichiometry with respect to the hydroxyl functions of said alcohol, and the acid catalyst,  monomer is then added to the medium with a rate of addition close to half the consumption rate of the perfluoroalkylated oxirane.  9 / - A method of preparation according to one of claims 5, 6, 7 or 8, wherein the monomer is added for a period of between 1 and 60 hours, the temperature of the reaction medium is between 200C and 800C.  10 / - A method of preparation according to one of revendicaitons 5, 6, 7, 8 or 9, wherein or uses a chlorinated hydrocarbon solvent as an inert solvent.  11 / - Method according to one of claims 5 to 10, wherein the alcohol used is a monoalcohol, a diol, a triol or a monomer or copolymer tetrol.  12 / - The method of claim 5 for the preparation of a perfluoroalkylated macrodiols homopolymer, wherein the alcohol used is a monomeric diol.  13 / - The method of claim 5 for the preparation of a monohydroalkyl perfluoroalkyl homopolymer, wherein the alcohol used is a monomeric monoalcohol.  14 / - Method according to one of claims 5 or 6 for the preparation of a perfluoroalkylated hydroxylated macromonomer, wherein the alcohol used is a monomeric alcohol having a polymerizable group.  15 / - Method according to one of claims 5 or 6 for the preparation of a tri-perfluoroalkylated α-macrodiol, in which the alcohol used is a copolymer diol.  16 / - Method according to one of claims 5 or 6 for the preparation of a perfluoroalkyl polyol, wherein the alcohol used is a triol or a tetrol.  17. The method as claimed in claim 6 for the preparation of a monohydroxylated diblock copolymer, in which the alcohol used is a polymeric monoalcohol.  18 / - Preparation process according to one of claims 5 to 17, wherein the catalyst used is a superacidic catalyst having a Hammet acidity function less than -6.  19 / - The method of claim 18 wherein the acid catalyst is selected from the following compounds: BF3 etherate, HBF4 etherate, CH3SO3H.  20 / - Process for the preparation of fluorinated polyurethanes, characterized in that  in a first step, a hydroxylated polyether according to one of claims 1, 2 or 4 is reacted with an organic diisocyanate in order to obtain a perfluoroalkylated diisocyanate prepolymer,  in a second step, polymerization of said prepolymer is carried out in the presence of a crosslinking agent and / or a chain extender.  21 / - Preparation process according to claim 20, wherein using a diisocyanate of the following group: hexamethylene diisocyanate, isophorone diisocyanate, toluene diisocyanate, 4,4'-diphenyl methane diisocyanate, trimethyl hexamethylene diisocyanate.  22 / - Preparation process according to one of claims 20 or 21, wherein the aliphatic diols or triols, polyesters glycols, polyether glycols or aliphatic diamines or aliphatic diamines or aliphatic diamines or aromatics.