FR2828685A1 - Compounds comprising a carboxylic ester function of an alkyl phosphonate and their preparation, useful as charge coatings or dispersants on metals and as monomers for polymerisation - Google Patents

Abstract

Alkyl alkyl phosphonate compounds with carboxylic ester functions used as metal coatings and charge dispersants and in polymerisation reactions. Independent claims are also included for their preparation and uses.

Description

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COMPOUNDS COMPRISING AT LEAST ONE ESTER FUNCTION
CARBOXYLIC ALKYLPHOSPHONATE ALKYL
The present invention relates to compounds comprising at least one alkylphosphonate alkyl carboxylic ester function, their preparation and their uses.

 European Patent Application No. EP-A-960889 relates to an aqueous dispersion of polymers which can be obtained by polymerization of an emulsion of a mixture of monomers which may contain in particular alkyl (meth) acrylates and unsaturated ethylenic monomers having at least one phosphonate group.

These latter monomers are derived from vinylphosphonic acid, 2-methacrylamido-2-methylpropanephosphonic acid, propene-2-phosphonic acid or α-phosphonostyrene acid.

 This dispersion is used as a binder for anti-corrosion coating.

 Also known from US Pat. No. 3,030,347 are acrylate and methacrylate copolymers of dialkyl phosphonates.

 These copolymers are used as flame retardant materials, as additives for oily lubricating compositions, as coatings or in the treatment of leather or textile materials.

 They are prepared from (dialkylphosphono) alkyl (meth) acrylate.

 It is an object of the invention to provide compounds which can be used to disperse fillers or to coat metals and, where appropriate, which can also be starting materials for synthesizing polymers having good adhesion to various solid supports, such as than metals and glass.

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 Thus, the subject of the invention is compounds comprising at least one carboxylic ester function of alkyl alkyl phosphonate.

 Such compounds have, by virtue of their free phosphonic acid function, good dispersion and adhesion properties on solid supports, as well as good aptitude for the formation of metal complexes.

 The invention also relates to a process for the preparation of a compound comprising at least one carboxylic ester function of alkyl alkyl phosphonate.

 This process comprises a step E in which a starting ester function, which is a dialkylalkylphosphonate carboxylic ester function, is converted into an alkylphosphonate carboxylic ester function.

 This method has the advantage of being easy to implement.

 The invention also relates to the use of compounds according to the invention which are unsaturated esters, as monomers in a polymerization reaction.

 Other features and advantages of the invention will now be described in detail in the following description.

Compounds according to the invention
The compounds according to the invention comprise at least one carboxylic ester function of alkyl alkyl phosphonate, that is to say a function G corresponding to the formula -COO-AP (O) (OH) (OR '), in wherein A is an alkylene group and R is an alkyl group.

The compounds according to the invention can therefore have the following general formula: [RCOO-A-PO (OH) (OR ')] n [M] p [M'] q in which:
R is an organic residue;
A is an alkylene group having 1 to 3 carbon atoms;

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R is an alkyl group having 1 to 6 carbon atoms; n is an integer greater than 0;
M and M 'are units derived from ethylenically unsaturated monomers; p and q are integers.

 Preferably, the alkylene group A is the ethylene-CH 2 -CH 2 group.

 R is preferably an alkyl group having 1 to 3 carbon atoms and in particular the methyl group.

Generally, the integers n, p and q satisfy the following condition:

<Tb>
<tb> 1 <SEP><SEP> n + p + q <SEP><SEP> 10000
<Tb>
Preferably:

<Tb>
<tb> 100 <SEP><SEP> n + p + q <SEP><SEP> 1000 <SEP>;
<tb> 0 <SEP><<SEP> n / <SEP> (n + p + q) <SEP><<SEP> 0.5 <SEP>;
<tb> 0 <SEP><<SEP> p <SEP> (n + p + q) <SEP><<SEP> 0, <SEP> 99 <SEP>;<SEP> and
<tb> 0 <SEP><<SEP> q / <SEP> (n + p + q) <SEP><<SEP> 0, <SEP> 99.
<Tb>

 The units M and M'can originate from ethylenically unsaturated monomers chosen from the following compounds: methyl, ethyl, propyl or butyl acrylate; methyl, ethyl, propyl and butyl methacrylate; (meth) acrylic monomers, olefins; vinyl monomers, in particular styrene, methylstyrenes, propylstyrenes, butylstyrenes and decylstyrenes.

 According to the invention, any function G, as it has just been defined, is fixed on an organic residue R, the latter encompassing numerous definitions.

 Thus, according to a first preferred embodiment of the invention, R is a residue of acrylic acid or

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 methacrylic acid, n is 1 and p and q are zero.

 The compound according to the invention is therefore an ester which can therefore have the general formula CH 2 = C (R 1) -COO-A-P (O) (OH) (OR '), in which R 1 is a hydrogen atom or a methyl group, A and R 'are as defined above.

 Preferably, R 1 is the methyl group.

 According to a second preferred embodiment of the invention, R is the residue of a polymer and p and q are zero.

 Thus, the compound according to the invention may be a polymer comprising at least one unit of formula - [CH 2 -C (R 1) COO-AP (O) (OH) (OR ')] - in which R 1, A and R' are as defined according to the first aspect of the invention.

Process according to the invention
Whatever the organic radical R, the compound according to the invention is advantageously prepared from a starting material having at least one starting ester function, which is a carboxylic ester function of dialkyl alkylphosphonate, by conversion of this starting ester function to the carboxylic ester function of the desired alkyl alkyl phosphonate.

 The starting ester function Go corresponds to the formula -COO-A-P (O) (OR ') 2, in which A and R' are as defined above.

 The method according to the invention then comprises a conversion step E, in which all the Go functions are converted into G functions.

Starting product
The starting material can be a product of formula

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 wherein R2 is hydrogen or alkyl, such as methyl, R1 and R5 are as previously defined.

 Such a starting product can be prepared according to the teachings of the aforementioned US Pat. No. 3,030,347.

dans laquelle :
Ri et R'sont tels que définis précédemment ; m est un entier de 1 à 3. The starting material may also be a dialkyl alkylphosphonate (meth) acrylate having the formula:

in which :
Ri and R 'are as previously defined; m is an integer of 1 to 3.

dans laquelle : R''est un groupement alkyle ayant de 1 à 4 atomes de carbone ; et
Ri est tel que défini précédemment. Such dialkyl alkylphosphonate (meth) acrylate can be prepared as described below. l) Reagents
Starting from an alkyl (meth) acrylate Ao of formula:

wherein: R 'is an alkyl group having 1 to 4 carbon atoms; and
Ri is as defined above.

 As alkyl (meth) acrylate Ao, mention may be made of methyl, ethyl, propyl, butyl acrylates and methyl, ethyl, propyl and butyl methacrylates.

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dans laquelle m est un entier de 1 à 3. The process is then carried out, in particular, as described in French Patent Application No. 0013618 filed October 24, 2000, that is to say that the alkyl (meth) acrylate Ao is reacted with a dialkylphosphonated alcohol B, Formula

in which m is an integer of 1 to 3.

dans laquelle R'a la signification donnée ci- dessus, et un ester insaturé D de formule

dans laquelle
R3 est un groupement alkyle comportant de 1 à 4 atomes de carbone, de préférence un méthyle n'vaut 0 ou 1. To obtain such a dialkylphosphonated alcohol B in which m is 2 or 3, a radical reaction is carried out in a conventional manner between a dialkyl hydrogen phosphate C of formula

in which R'a has the meaning given above, and an unsaturated ester D of formula

in which
R3 is an alkyl group having 1 to 4 carbon atoms, preferably methyl is 0 or 1.

An intermediate F obtained is thus obtained, of formula:

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in which
R3, R 'have the meanings given above m is 2 or 3; which is saponified to result in phosphonated alcohol B.

 To obtain a dialkyl hydroxyalkylphosphonate alcohol in which m is 1, a dialkyl hydrogen phosphonate C is conventionally reacted with formaldehyde.

2) Reaction of alkyl (meth) acrylate Ao with phosphonated alcohol B
This reaction is a transesterification reaction. It is therefore carried out under the usual conditions of transesterification reactions well known to those skilled in the art.

 The temperatures employed are in general 85 ° C. to 130 ° C., preferably 950 ° C. to 120 ° C.

 The ratio of the reagents, namely (meth) acrylic ester Ao: phosphonated alcohol B varies within wide limits, for example between 1.4 and 5, preferably between 2 and 4.

1-4-2 10-1, de préférence entre 5. 10-4 et 5. 10-2 mol/mol d'alcool. Preferably, the reaction is carried out in the presence of a catalyst, in an amount of between 10 -4 and

1-4-2 10-1, preferably between 5. 10-4 and 5. 10-2 mol / mol of alcohol.

 As a catalyst, zirconium acetylacetonate is preferably used.

Step E of conversion
Step E consists in hemihydrolysing the phosphonic diester part, that is to say, to retain an ester function and to hydrolyze the other, so as to obtain a monoacid.

 Surprisingly, the inventors have managed to develop a step E which leads selectively to the monoacid. This step E comprises, on the one hand, a reaction with a metal halide and on the other

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 on the other hand, the acidification of the intermediate salt obtained to give the monoacid.

 In addition, the inventors have found that during this step E, the carboxylic ester function which is normally sensitive to acid hydrolysis, was not affected at all.

 The metal halide used is preferably an alkali metal, in particular sodium.

 The halogen may be chlorine, bromine or iodine, preferably iodine.

 With regard to the quantities used, it is desirable that the molar ratio between the functions Go and the metal halide be between 1: 1 and 1: 3 and in particular between 1: 1 and 1: 2.

 In general, the reaction with the metal halide is carried out in a conventional solvent such as acetone, methyl ethyl ketone or another polar solvent such as methanol, at a temperature of between 50 and 90 ° C., preferably between 50 and 80 ° C, at atmospheric pressure and for a period of 8 to 48 hours, preferably 10 and 24 hours.

 The acidification of the intermediate salt is carried out in a known manner, for example by passing through a cation exchange resin, such as sulfonic functions or by acidification with a strong acid, in an aqueous medium.

 Step E according to the invention can be carried out at different stages of the synthesis of the compound according to the invention.

 Thus, for example, when the compound according to the invention is a polymer, step E can convert Go functions to G functions, whereas these Go functions are already carried by a polymer.

 In this manner, a (meth) acrylic copolymer can be prepared by a process comprising: a) copolymerizing a carboxylic ester monomer having the formula CH2 = C (R1) -COO

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A-P (O) (OR ') 2, R1, A and R being as defined above, with at least one ethylenically unsaturated monomer; and b) the implementation of step E on the copolymer obtained above.

 In a variant, it is possible to begin by implementing step E to convert Go functions to G functions when these Go functions are still carried by the monomer. Then, the polymerization is carried out.

In this case, a (meth) acrylic copolymer can be prepared by a process comprising: a) carrying out step E on a carboxylic ester monomer having the formula
CH 2 = C (R 1) -COO-AP (O) (OR ') 2, R 1. A and R being as defined above; and b) the copolymerization of the product obtained above with at least one ethylenically unsaturated monomer.

 Ethylenically unsaturated monomers that may be mentioned include the following compounds: methyl, ethyl, propyl and butyl acrylate; methyl, ethyl, propyl and butyl methacrylate; (meth) acrylic monomers - olefins; vinyl monomers, in particular styrene, methylstyrenes, propylstyrenes, butylstyrenes and decylstyrenes.

uses
The compounds according to the invention can be used for coating metals or dispersing fillers.

 In addition, the compounds according to the invention which are unsaturated esters of general formula CH 2 = C (R 1) -COO-A-P (O) (OH) (OR '), as defined above, may advantageously be used as monomers in many polymerization reactions.

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 The polymerizations may be carried out in solution, in emulsion or in bulk.

 Copolymers, terpolymers or copolymers with more than three monomers can thus be prepared.

 Such copolymers or terpolymers, because they carry monoacid phosphonic groups, have good adhesion to various solid supports such as metals and glass.

 In addition, a single P-OH function per phosphorus atom is sufficient to provide adhesion properties to the polymer.

 Finally, the complexing activity of a phosphonic group on a given surface has the advantage of being greater than that of a carboxylic group.

Examples
The following examples are given for illustrative purposes only. They have no limiting character.

Example 1
Synthesis of methyl ethylphosphonate methacrylate (Step E on monomer)
In a 100 ml flask equipped with a condenser and a magnetic stirrer, dimethyl ethylphosphonate methacrylate (2.22 mg, 0.01 mole), dimethyl iodide (2.25 g, 0.015 mole) are introduced. sodium and 30 ml of anhydrous acetone.

 The solution was refluxed for 14 hours and then allowed to stir at room temperature for 6 hours.

 The solid is filtered under vacuum and washed twice with anhydrous acetone.

 After evaporation of the solvent under reduced pressure, 1.67 g of the sodium salt is recovered in the form of a colorless crystalline solid, a yield of 73%.

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 The sodium salt is solubilized in 25 ml of methanol and acidified by passage over an amberlite IRA 120 ion exchange sulfonic resin. The methanol is then evaporated under reduced pressure.

 Thus 1.50 g of methyl ethylphosphonate methacrylate are collected. The corresponding yield is quantitative.

Example 2
Preparation of a methyl methacrylate / methyl ethyl phosphonate methacrylate copolymer in solution a) Preparation of the polymer
8.0 g (80 mmol) of freshly distilled methacrylate, 4.44 g (20 mmol) of dimethyl ethylphosphonate methacrylate and 100 ml of anhydrous acetonitrile are introduced into a bicol. The reaction mixture is degassed under nitrogen for 15 minutes and brought to 75 C. 82 mg of 2,2'-azo-bis-isobutyronitrile (AIBN) 0.5 mol% dissolved in 1 ml of acetonitrile are then added. The mixture is stirred for 48 hours. Subsequently, after concentration, the polymer is precipitated in technical pentane and dried under vacuum.

11.2 g of a fine white powder are thus obtained, ie a yield of 90%. b) Step E on Polymer
100 g of the copolymer obtained above, 2.4 g of sodium iodide (16 mmol) and 100 ml of anhydrous acetone are introduced into a 100 ml flask equipped with a condenser and a magnetic stirrer. The solution is refluxed for 24 hours and then stirred at room temperature for 24 hours.

 7.1 g of sodium salt are thus collected by filtration after drying under vacuum, ie a yield of 70%.

 The sodium salt is solubilized in 100 ml of methanol and acidified by passage over a sulfonic ion exchange resin AMBERLITE IRA "" 120. We

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 The solution is concentrated under reduced pressure and the acidic polymer is precipitated in ethyl ether.

 6.8 g of copolymer are thus collected. The corresponding yield is quantitative.

Example 3
Preparation of a copolymer of methyl methacrylate / (hydrogenomethylphosphono) ethyl methacrylate in solution (polymerization of the ester monomer according to the invention)
To a bicol of 250 ml, 8.0 g (80 mmol) of freshly distilled methyl methacrylate, 4.16 g (20 mmol) of methyl ethylphosphonate methacrylate obtained in Example 1 and 100 ml of anhydrous acetonitrile. The reaction mixture is degassed with argon for 15 minutes and heated to 75 ° C.. 82 ml of AIBN (0.5 mol%) dissolved in 1 ml of acetonitrile are then added. The mixture is stirred for 48 hours. Subsequently, after concentration, the polymer is precipitated in technical pentane and dried under vacuum.

 10.9 g of a fine white powder are thus obtained, ie a yield of 90%.

Example 4
Preparation of a methyl methacrylate / methyl ethyl phosphonate methacrylate copolymer in emulsion (polymerization of the ester monomer according to the invention)
500 g of water, 8 g of a 10% by weight solution of SLS (sodium lauryl sulfate, surfactant) and 12 mg of sodium hydrogenphosphite are introduced into a 500 ml reactor. Stirring is carried out for 10 minutes. 14.0 mg of freshly distilled methyl methacrylate and 5.6 g of methyl ethylphosphonate methacrylate obtained in Example 1 are then added. The reaction mixture is degassed under nitrogen for 15 minutes and heated to 800 ° C. We then add 3.65

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 g of a solution of PPS (potassium persulfate, initiator) at 5% by weight (0.4 mol% relative to the monomers). The mixture is stirred for 2 hours. A solution of 5 g of water, 37 mg of SLS and 114 mg of IRGANOX 1076 (antioxidant) is added. The mixture is left stirring for 30 minutes and the reaction mixture is cooled to room temperature.

 A latex is obtained. The measurement of dry extract shows that the reaction is quantitative.

Example 5
Preparation of a terpolymer of methyl methacrylate / n-butyl acrylate / methyl ethylphosphonate methacrylate in solution (polymerization of the ester monomer according to the invention)
4.3 g (43 mmol) of methyl methacrylate and 4.3 g of freshly distilled n-butyl acrylate and 1.5 g (7.2 mmol) of methacrylate are introduced into a 100 ml bicolar. Methyl ethylphosphonate obtained in Example 1 and 50 ml of anhydrous acetonitrile.

 The reaction mixture is degassed with argon for 15 minutes and heated to 800C. 80 ml of AIBN (0.5 mol%) dissolved in 1 ml of acetonitrile are then added. The mixture is stirred for 15 hours. Subsequently, acetonitrile and residual monomers are evaporated under reduced pressure to constant weight. 9.6 mg of a viscous and sticky paste are thus obtained, ie a yield of 95%.

Claims (15)

1. A compound comprising at least one carboxylic ester function of alkyl alkyl phosphonate. 2. Compound according to claim 1, corresponding to the formula [RCOO-A-PO (OH) (OR ')] n [M] p [M'] q, in which: R is an organic residue; A is an alkylene group having 1 to 3 carbon atoms; R is an alkyl group having 1 to 6 carbon atoms; n is an integer greater than 0; M and M 'are units derived from ethylenically unsaturated monomers; p and q are integers. The compound of claim 2 wherein: A is the ethylene group; R is an alkyl group having 1 to 3 carbon atoms, preferably the methyl group; the integers n, p and q satisfy the following condition: 1 <n + p + q <10000 and preferably under the following conditions:

<Tb> <tb> 0 <SEP> <<SEP> q / <SEP> (n + p + q) <SEP> <<SEP> 0, <SEP> 99. <tb> 0 <SEP> <<SEP> p <SEP> (n + p + q) <SEP> <<SEP> 0.99 <SEP>; <SEP> and <tb> 0 <SEP> <<SEP> n / <SEP> (n + p + q) <SEP> <<SEP> 0.5 <SEP>; <tb> 100 <SEP> <SEP> n + p + q <SEP> <SEP> 1000 <SEP>; <Tb>  4. Compound according to claim 2 or claim 3, wherein R is the group CH 2 = C (R 1) -, n is 1, p and q are zero and R 1 is a hydrogen atom or a methyl group. <Desc / Clms Page number 15> 5. Compound according to one of claims 1 to 3, wherein R is the residue of a polymer, p and q are zero and R1 is a hydrogen atom or a methyl group. 6. Process for the preparation of a compound according to one of claims 1 to 5, comprising a step E in which a starting ester function, which is a carboxylic ester function of dialkyl alkylphosphonate, is converted into a carboxylic ester function. alkyl alkyl phosphonate. 7. Process according to claim 6, characterized in that step E comprises a reaction with a metal halide followed by acidification. 8. Process according to claim 7, characterized in that the metal is an alkali metal, preferably sodium. 9. The method of claim 7 or claim 8, characterized in that the halogen is iodine. 10. Method according to one of claims 6 to 9, wherein, during the implementation of step E, the molar ratio between the carboxylic ester functions of dialkyl alkylphosphonate starting and the metal halide is between 1: 1 and 1: 3 and preferably between 1: 1 and 1: 2. 11. Process for the preparation of a compound according to claim 5, comprising: a) the copolymerization of a carboxylic ester monomer corresponding to the formula CH2 = C (R1) -COO-A- P (O) (OR ') 2, R1, A and R being as defined in claims 2 to 5, with at least one ethylenically unsaturated comonomer; and <Desc / Clms Page number 16>  b) the implementation of step E, as defined in claims 6 to 10, on the copolymer obtained above. A process for preparing a compound according to claim 5 comprising: a) performing step E as defined in claims 6 to 10 on a carboxylic ester monomer having the formula CH 2 = C (R 1) -COO-AP (O) (OR ') 2 R 1, A and R being as defined in claims 2 to 5, and b) the copolymerization of the product obtained above with at least one comonomer with ethylenic unsaturation. 13. The method of claim 11 or claim 12, characterized in that the ethylenically unsaturated comonomer is selected from the group consisting of methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate; - Methyl methacrylate, propyl ethyl, butyl; (meth) acrylic monomers, olefins; vinyl monomers, in particular styrene, methylstyrenes, propylstyrenes, butylstyrenes and decylstyrenes. 14. Use of a compound according to one of claims 1 to 5 for coating metals or dispersing fillers. 15. Use of a compound according to claim 4 in a polymerization reaction.