MXPA06004044A - Process for preparing amides based on polyetheramines and (meth)acrylic acid - Google Patents

Abstract

The invention provides a process for preparing amides from polyetheramines and (meth)acrylic acid or the corresponding anhydrides, the energy source used being microwaves.

Description

PROCEDURE TO PRODUCE AMIDAS BASED ON POLYETHERAMINES AND ACID (MET) ACRYLIC DESCRIPTIVE MEMORY The present invention relates to a process for producing amides of acrylic acid or methacrylic acid with polyetheramines by the use of microwaves as an energy source. The amides thus obtained serve as macromonomers, whose properties can be varied by the choice of the appropriate polyetheramine. The polyetheramines contain a polyalkylene glycol group. Depending on which constituents polyalkylene glycols form, different properties can be obtained. Water-soluble compounds with a high proportion of polyethylene glycols and are soluble in water are then obtained by the use of polyethylene glycols. In addition, its melting point and its viscosity can be influenced by modifying the molar masses of the polyalkylene glycols. By using different starting alcohols for the alkoxylation, surfactant properties can be obtained. Branched systems can also be formed with polyvalent alcohols, which then give rise, after aminolosis and amidation, to monomers with crosslinking effect. This results in multiple possibilities of selectively influencing, by means of polyalkylene glycols based macromonomers, on the properties of a polymer based thereon.

Among the amines of the olefinically unsaturated carboxylic acids, (meth) acrylic acid amides are of particular interest, since they represent starting materials for producing polymers and copolymers, which can be applied in multiple areas. The term "(meth) acrylic acid amides" represents methacrylic acid amides and acrylic acid amides. An advantage of the amides with respect to the corresponding esters is the greater stability that occurs, for example, due to the lower sensitivity to hydrolysis. In the production of amides from amines with acid (met) acrylic, you can observe different problems. An undesired side reaction is the Michael addition of the amines to the double bond of the unsaturated carboxylic acid. The (meth) acrylic acid derivatives also tend to polymerize under the influence of heat or light. Especially in the production and purification by distillation, they are exposed to temperatures that can easily cause unwanted polymerization. The antepor technique offers different processes for producing (meth) acrylic acid amides. DE-A-28 16 516 describes a process by which (meth) acrylic acid amines are produced from esters of alkyl (meth) acrylic acid. In this case, we work to avoid Michael's adducts in the presence of dibutyltin oxide.

DE-A-31 23 970 describes a process by which amines of (meth) acrylic acid are produced from esters of alkyl (meth) acrylic acid. We work in this case to avoid the adducts of Michael in the presence of compounds of the metals of the fourth subgroup and / or compounds of the metals lead, tantalum and / or zinc as catalysts. EP 0 992 480 A1 discloses a process for producing esters of (meth) acrylic acid by the use of microwaves as an energy source. However, amides are not produced according to this method. Of special interest are the macromonomers based on polyalkylene glycols, since the hydrophilic / hydrophobic nature of the macromonomer can be selectively influenced here, by the use of alkylene oxides or hydrophobic and / or hydrophilic starting compounds with the corresponding properties in the production of the polyakylene glycol that serves as the base. With the use of polyakylene glycols in chemical reactions, there is often the problem of the high tendency to polymerization. Due to the frequently high molar masses, the substances are relatively unreactive and the products can not be purified by distillation. Therefore, special requirements are placed on the synthesis with polyakylene glycols. It was then surprisingly found that amides can be produced from polyetheramines and (meth) acrylic acid, using microwaves as an energy source. In this case the formation of Michael addition products is suppressed, so that the desired amines are obtained in high yield and purity. The object of the invention is therefore a process for producing (meth) acrylic acid amides, by mixing a polyetheramine of the formula 1 R2 - N ~ R3 I O) H wherein R 2 represents an organic radical, which comprises between 2 and 600 alkoxy groups, and R 3 represents hydrogen or an organic radical with 1 to 400 carbon atoms, with (meth) acrylic acid and the mixture is irradiated with microwaves. R2 contains from 2 to 600 alkoxy groups. Under the alkoxy groups is commonly understood a unit of the formula - (AO) -, in which A represents an alkylene group of C2 to C4. From 2 to 600 alkoxy groups mean alkoxy a structural unit of the formula - (AO) n- with n = 2 to 600. In the alkoxy chain represented by - (AO) n-, A preferably represents an ethylene or propylene radical, in particular an ethylene radical.

The total number of alkoxy units is preferably between 5 and 300, in particular between 8 and 200. In the alkoxy chain, it can be a block polymer chain having alternating blocks of different alkoxy units preferably ethoxy and propoxy units . It can also be a chain with a statistical sequence of alkoxy units or a homopolymer. In a preferred embodiment, - (A-O) n- represents an alkoxy chain of formula 2 - (CH2-CH (CH3) -O) a- (CH2-CH2-O) b- (CH2-CH (CH3) -O) c- (2) in which a) is a number from 0 to 300, preferably from 0 to 80, b) is a number from 3 to 300, preferably from 3 to 200, c) is a number from 0 to 300, preferably from 0 to 80. R3 is hydrogen or an organic radical with 1 to 400 atoms of carbon. R3 may contain, together with carbon and hydrogen, heteroatoms such as oxygen, nitrogen, phosphorus or sulfur. In a preferred embodiment, R3 is hydrogen, an alkyl radical with 1 to 50 carbon atoms, an alkenyl radical with 2 to 50 carbon atoms, an aryl radical with 6 to 50 carbon atoms or an alkylaryl radical with 7 to 50 atoms of carbon. In another preferred embodiment, R3 corresponds to the same definition as R2. In another preferred embodiment, R3 contains amino groups. Preferably, R3 then corresponds to formula 3 wherein R 4 can be a divalent hydrocarbon group with 1 to 50 carbon atoms and R 5 and R 6 can each be hydrogen or a monovalent hydrocarbon group with 1 to 50 carbon atoms, wherein each of R 4, R 5 and R 6 can comprise from 1 to 200 alkoxy groups and can contain also heteroatoms such as oxygen, nitrogen, phosphorus or sulfur (basically as R3), and m represents a number from 1 to 10.

The products obtained in the process according to the invention from a monoamine correspond to formula 4 wherein R2 and R3 have the meaning indicated above and R1 represents hydrogen or methyl. If the polyetheramine is a diamine of formula 5 R¿-N-R 4 -N-Rb (5) H H then the product obtained according to the procedure according to invention corresponds to formula 6 accordingly, tri-, tetra- or pentamethacrylamides can be produced from tri-, tetra- or pentafunctional amines. Thus, for example, a structure of formula 7 (7) wherein k- ?, k2, k3 and l4 represent integers, which give the sum up to 600. In another preferred embodiment, the amine of formula (1) represents a polyamine of formula 8 R7 (NHR8) n (8) wherein R7 represents an organic radical of n-valences with 2 to 400 carbon atoms, which may also contain heteroatoms such as oxygen, nitrogen, phosphorus or sulfur, R8 represents a radical such as R3, and n represents an integer from 2 to 20 .

If R7 represents alkoxylated glycerin, then the product of the process according to the invention may have, for example, the following structure: (9) in which the kp indices are integers, which give in the sum up to 600. As polyetheramines monovalent or polyvalent amines can be used, which can be branched, unbranched or cyclic, saturated or unsaturated. Such amines are, for example, monovalent amines, such as, for example, alkyl polyalkylene glycols, such as, for example, methyltriethylene glycolamine.(metiltrietilenglicol) amine, butiltrietilenglicolamina, laurilpolipropilenglicolamina, metiltripropilenglicolamina, fenolpolipropilenglicolamina, iso-tridecilpolipropilenglicolamina, b¡s (metiltriprop¡lenglicol) am¡na, N-methyl-metilpolipropilenglicolamina, metilpolipropilenglicolamina, (met¡lpolipropilenglicol) amine, with distribution metilpolialquenilglicolamina statistics or in the form of blocks of the ethylene- and propylene glycol units, divalent amines, such as, for example, triethylene glycol diamine, tripropylene glycol diamine, polyethylene glycol diamine, polypropylene glycol diamine, polyalkylene glycol diamine with statistical or block-like distribution of the ethylene and propylene glycol units, butanediol polyalkylene glycol diamine, polyalkylene glycol diamine resorcinums, trivalent amines, such as, for example, glycerin polyalkylene glycoltriamine with statistical or block-like distribution of the ethylene- and propylene glycol units, (triethylene glycollamine) amine, (propylalkylene glycollamin) amine, tetravalent amines, such as, for example, pentaerythrolypolyalkylene glycol with statistical distribution or in the form of blocks of ethylene and propylene glycol units, N, N'-(polypropylene glycol amine) -polyalkylene glycol diamine. The molar ratio amine: (meth) acrylic acid is preferably in the range of 1: 0.2 to 15, in particular in the range of 1: 0.8 to 15. To avoid polymerization during the amidation reaction, the stabilizers can be used known according to the prior art. The usual stabilizers are N-oxyls such as for example 4-hydroxy-2,2,6,6-tetramethyl-oxyl-piperidine, 4-oxo-2,2,6,6-tetramethylpiperdin-N-oxy, phenols and naphthols such as for example hydroquinone, naphthoquinone, p-aminophenol, p-nitrosophenol, 2-tert-butylphenol, 4-tert-butylphenol, 2,4-di-tert-butylphenol, 2-methyl-4-tert-butylphenol, 4 -methyl-2,3-di-tert-butylphenol, lonol K 65®, p-methoxyphenol, butylhydroxyanisole or 4-amines, such as N, N-diphenylamine, phenylenediamines, such as N, N'- alkyl-para-phenylenediamines, in which the alkyl radicals may be the same or different, hydroxylamines, such as for example N, N-diethylhydroxylamine, phosphorus-containing compounds, such as for example triphenylphosphine, triphenylphosphite or triethylphosphite or compounds which they contain sulfur, such as for example sulfur dioxide, diphenyl sulfide, phenothiazine or 5-tert-butyl-4-hydroxy-2-methylphenyl sulfide, as well as the types of Irganox® types of Cupferron® and sulfur salts. These compounds can be used alone or in mixtures. The amounts reach from 10 ppm to 5% by weight, especially from 50 ppm to 3% by weight, relative to the amine used. A reaction can be carried out in an inert gas atmosphere (such as nitrogen, argon, helium) or also optionally with the addition of air or gas mixtures containing oxygen. Amidation can be carried out without or with catalyst. The catalysts known in accordance with the prior art can be used in this case. The usual catalysts are sulfuric acid, hydrogen sulfide, disulphuric acid, polysulfuric acids, sulfur trioxide, methanesulfonic acid, benzenesulfonic acid, C1-C30 alkylbenzenesulfonic acid, naphthalene sulphonic acid, sulfuric acid monoester of C1-C30 alcohols such as dodecyl sulfate. , phosphoric acid, phosphorous acid, hypophosphorous acid, polyphosphoric acid, phosphoric acid ester of C1-C30 alcohols, hydrochloric acid, perchloric acid, acidic ion exchangers, heteropolyacids, "solid super acids", as well as salts of these acids, Lewis such as boron trichloride, aluminum sulfate and iron trichloride. The catalyst is optionally used in amounts preferably of 0.01 to 10, in particular 0.05 to 5% by weight, relative to the total reaction mixture. Amidations can be carried out at temperatures of 40 to 250 ° C. It is preferably worked in the interval of 80 to 210 ° C. Amidation is preferably carried out with an acid supernatant (met) acrylic. It is preferably worked in a pressure range of 1 mbar to 10 bar. Amidation can be carried out continuously or discontinuously. The amidation is preferably carried out without solvents. However, solvents can also be used. To produce the microwaves, the methods and apparatuses customary in the art can be used. Usually, the frequency of the microwaves is in the range between 300 MHz and 300 GHz, which corresponds to a wavelength of 1 m to 1 mm. Usually, frequencies are used in the 850-950 or 2300-2600 MHz range, since those frequencies are not required for communication purposes. The microwaves can be transmitted according to known methods to the reaction medium. Both multi-mode and single-mode devices can be used.

EXAMPLES For examples 1 to 5, a microwave generator from the company CEM, model "Discover" was used. For examples 6 to 8, a microwave appliance of the MLS company, model "MLS-ETHOSplus" was used. For comparative example 1, a conventional oil bath was used as a heat source.

EXAMPLE 1 1 g of a methylpolyalkylene glycol amine (ethylene glycol propylene glycol mixture) with an average molar mass of 750 g / mol and 0.34 g of methacrylic acid was poured into a high pressure vessel with stirrer. The high pressure vessel was sealed and the reaction mixture was irradiated at 290 W for 10 minutes under stirring and air cooling, so that the maximum temperature would rise to about 210 ° C. By integration by means of 1 H NMR spectroscopy, a degree of conversion of > 98%.

EXAMPLE 2 1 g of a methylpolyalkylene glycol amine (ethylene glycol propylene glycol mixture) with an average molar mass of 1250 g / mol and 0.4 g of methacrylic acid was poured into a high pressure vessel with stirrer. The high pressure vessel was sealed and the reaction mixture was irradiated at 290 W for 10 minutes under stirring and air cooling, so that the maximum temperature would rise to about 170 ° C. By integration by means of 1 H NMR spectroscopy, a degree of conversion of > 98%.

EXAMPLE 3 1 g of a methylpolyalkylene glycol amine (mixture of ethylene glycol propylene glycol) with an average molar mass of 2000 g / mol and 0.2 g of methacrylic acid was poured into a high pressure vessel with stirrer. The high pressure vessel was sealed and the reaction mixture was irradiated at 290 W for 10 minutes under stirring and air cooling, so that the maximum temperature would rise to about 160 ° C. By integration by means of 1 H NMR spectroscopy, a degree of conversion of > 98%.

EXAMPLE 4 1 g of a glycerol-based polyalkylene glycol (mixture of ethylene glycol propylene glycol) with a mean molar mass of 2500 g / mol and 0.6 g of methacrylic acid was poured into a high pressure vessel with stirrer. The high pressure vessel was sealed and the reaction mixture was irradiated at 290 W for 10 minutes with stirring and air cooling, so that the maximum temperature would rise to about 180 ° C. By integration by means of 1 H NMR spectroscopy, a degree of conversion of > 98%.

EXAMPLE 5 g of a methylpolyalkylene glycol amine (ethylene glycol propylene glycol mixture) with an average molar mass of 1000 g / mol and 10.4 g of methacrylic acid were poured into a high pressure vessel with stirrer. The high pressure vessel was sealed and the reaction mixture was irradiated at 300 W for 40 minutes under stirring and air cooling, so that the maximum temperature did not exceed 180 ° C. For the purification, the reaction solution was added to 50 ml of dichloromethane, after finishing the reaction. It was extracted by stirring once with 50 ml of a 1N HCl solution. The organic phase was washed twice with 50 ml of a cold saturated NaHCO 3 solution and subsequently washed with water.

It was dried over magnesium sulfate and the solvent was removed in a rotary evaporator. The product was characterized by infrared (IR) or nuclear magnetic resonance (NMR) chromatography, as well as by mass spectrometry (MALDI-TOF). The yield was 85%.

EXAMPLE 6 g of a methylpolyalkylene glycol (mixture of ethylene glycol propylene glycol) with an average molar mass of 2000 g / mol, 8 mg of phenothiazine, 8 mg of para-methoxyphenol and 4.3 g of methacrylic acid were poured into a high pressure vessel of polytetrafluoroethylene with agitator. The high pressure vessel was sealed and the reaction mixture was irradiated with stirring for 6 hours, the irradiation performance being regulated, so that the internal temperature was at 200 ° C. By integration by means of H NMR spectroscopy, it was possible to establish a degree of conversion of > 90% EXAMPLE 7 g of a polyalkylene glycol amine (a mixture of ethylene glycol propylene glycol) with an average molar mass of 1500 g / mol, 7 mg of phenothiazine, 7 mg of para-methoxyphenol and 11.5 g of methacrylic acid were poured into a high-pressure vessel of polytetrafluoroethylene with agitator. The high pressure vessel was sealed and the reaction mixture was irradiated with stirring for 6 hours, the irradiation performance being regulated, so that the internal temperature was at 200 ° C. By integration by means of 1 H NMR spectroscopy, a degree of conversion of > 92% EXAMPLE 8 g of a resorcinol-based polyalkylene glycol (mixture of ethylene glycol propylene glycol) with an average molar mass of 2300 g / mol, 10 mg of phenothiazine, 10 mg of para-methoxyphenol and 11.2 g of methacrylic acid were poured into a container of high pressure polytetrafluoroethylene with agitator. The high pressure vessel was sealed and the reaction mixture was irradiated with stirring for 6 hours, the irradiation performance being regulated, so that the internal temperature was at 200 ° C. By integration by means of 1 H NMR spectroscopy, a degree of conversion of > 90% COMPARATIVE EXAMPLE 1 (Thermal heating) g of a methylpolyalkylene glycol (mixture of ethylene glycol propylene glycol) with an average molar mass of 2000 g / mol, 8 mg of phenothiazine, 8 mg of para-methoxyphenol and 4.3 g of methacrylic acid were poured into a high-pressure glass vessel with agitator. The high pressure vessel was sealed and the reaction mixture was heated with stirring for 6 hours, the irradiation yield being regulated, so that the internal temperature was at 200 ° C. Already before reaching the desired reaction temperature, undesired polymerization of the reaction mixture began.

Claims (8)

NOVELTY OF THE INVENTION CLAIMS

1. - A process for producing (meth) acrylic acid amides, by mixing a polyetheramine of the formula 1 R2 - N - R3 I (O H wherein R 2 represents an organic radical, which comprises between 2 and 600 alkoxy groups, and R 3 represents hydrogen or an organic radical with 1 to 400 carbon atoms, with (meth) acrylic acid and the mixture is irradiated with microwaves.

2. The process according to claim 1, further characterized in that R3 is hydrogen, an alkyl radical with 1 to 50 carbon atoms, an alkenyl radical with 2 to 50 carbon atoms, an aryl radical with 6 to 50 carbon atoms. carbon or an alkylaryl radical with 7 to 50 carbon atoms.

3. The method according to claim 1 and / or 2, further characterized in that R3 corresponds to the same definition as R2.

4. The process according to one or more of claims 1 to 3, further characterized in that R3 contains amino groups.

5. - The method according to one or more of claims 1 to 4, further characterized in that R3 corresponds to formula 3 wherein R 4 can be a divalent hydrocarbon group with 1 to 50 carbon atoms and R 5 and R 6 can each be hydrogen or a monovalent hydrocarbon group with 1 to 50 carbon atoms, in which each of R4, R5 and R6 can comprise from 1 to 200 alkoxy groups, and m represents a number from 1 to 10.

The process according to one or more of claims 1 to 5, further characterized in that the amine of the formula ( 1) represents a polyamine of formula 8 R7 (NHR8) n (8) wherein R7 represents an organic radical of n-valences with 2 to 400 carbon atoms, R8 represents a radical such as R3, and n represents an integer from 2 to 20.

7. The process according to one or more of claims 1 to 6, further characterized in that the molar ratio amine: (meth) acrylic acid is preferably in the range of 1: 0.2 to 15 8.- The process according to one or several of claims 1 to 7, further characterized in that the amidations are carried out at temperatures of 40 to 250 ° C.