EP3107951A1

EP3107951A1 - Method for producing (meth)acrylic acid esters of polyalkoxy group-containing alcohols

Info

Publication number: EP3107951A1
Application number: EP15701801.1A
Authority: EP
Inventors: Andrea Misske; Uwe Meisenburg; Jochen Petzoldt; Virginie Bette; Bolette Urtel; Jean-Marc Ballin
Original assignee: BASF SE
Current assignee: BASF SE
Priority date: 2014-02-18
Filing date: 2015-01-30
Publication date: 2016-12-28
Also published as: CN106029741A; KR20160124148A; US20150232409A1; US9353043B2; WO2015124403A1; DE102014202963A1; JP2017511798A; TW201544525A

Abstract

Method for producing (meth)acrylic acid esters (E) of polyalkoxy group-containing alcohols by reacting polyalkoxy-group containing alcohols (P) of formula (I), where R1 represents hydrogen, a hydroxy group or a linear or branched, saturated or unsaturated, alcohol having from 1 to 30 C atoms, R², R³ represent independently of one another H or methyl, and m and n represent independently of one another a whole integer between 0 and 100, with the proviso that m and n may not simultaneously be 0, in the presence of at least one basic catalyst (K) having a pK_B value not above 7.0, with at least one sterically hindered polymerization inhibitor comprising a (meth) acrylic acid anhydride (A), characterized in that following completion of the reaction the reaction mixture is quenched with a C₁-C₆-alkanol.

Description

description

Process for the preparation of (meth) acrylic esters of polyalkoxy-containing alcohols

The present invention relates to a process for the catalytic production of

(Meth) acrylic acid esters of polyalkoxy-containing alcohols by reacting these alcohols with a (meth) acrylic anhydride. For the purposes of the present invention, (meth) acrylic acid is acrylic acid and / or methacrylic acid, acrylic acid esters and / or methacrylic acid esters (also referred to below as (meth) acrylates) and (meth) acrylic anhydride acrylic acid anhydride and or methacrylic anhydride understood. The preparation of (meth) acrylic esters is usually carried out by catalytic esterification of (meth) acrylic acid or transesterification of other (meth) acrylic acid esters with alcohols. In this case, strong acids or bases are often used, so that acid- or base-sensitive (meth) acrylic acid esters can not be selectively produced by an esterification or transesterification in this way as a rule.

(Meth) acrylic esters of polyalkoxy-containing alcohols are known. There are several documents in the literature which describe the transesterification of polyalkoxy-containing alcohols with a (meth) acrylic acid ester, for example in US Pat

EP 0 902 017 A1, JP 04 066555 A1 and DE 196 02 035 A1.

As an alternative to esterification or transesterification, the reaction of an alcohol with a (meth) acrylic anhydride is suitable.

FR 2 739 850 discloses a process for the preparation of (meth) acrylates of R-substituted polyalkoxy-containing alcohols having 3 to 60 EO and PO units by reaction with (meth) acrylic anhydride. The substituent R may be alkyl, aryl, alkylaryl or further substituted. The catalysts disclosed are Bronsted acids (sulfuric acid, alkyl or arylsulfonic acids), Lewis acids (BF 3) and amines (methylimidazole, diethylamine, triethylamine) in a concentration of 0.1 to 5% by weight.

The European application EP 1 820 812 A1 describes a process for preparing polyether (alkyl) acrylates by reacting the polyether alcohols with a (alkyl) acrylate in the presence of ligands contained metal catalysts of 3./4. Main group as well as the 3.-8. Subgroup.

DE 10 2008 040 214 A1 discloses the preparation of polyalkylene glycol di (meth) acrylates by reacting polyalkylene glycol with (meth) acrylic anhydride. The reaction takes place without the use of a catalyst. As polymerization inhibitors, the usual stabilizers as phenothiazine, hydroquinone monomethyl ether but also hindered phenols such as 2,4-dimethyl-6-tert-butylphenol recommended.

German Offenlegungsschrift DE 10 2004 042 799 A1 likewise discloses a process for the preparation of poly (C 2 -C 4 -alkylene glycol) mono (meth) acrylic acid esters. Again, the reaction of an alcohol with a (meth) acrylic anhydride in the presence of sterically hindered polymerization inhibitors by the use of basic catalysts such as sparingly soluble mono- to divalent metal oxides, hydroxides, carbonates and hydrogen carbonates. According to the disclosure, the water content in the reaction mixture is less than 0.2%, preferably less than 1000 ppm. It is recommended that at higher water contents, the water is first removed before the anhydride is added.

The methods disclosed in the prior art are disadvantageous in that water is added to the reaction mixture for the hydrolysis of the unreacted (meth) acrylic acid anhydride. However, this water must be removed again if water is undesirable for the further use of the (meth) acrylic acid esters of polyalkoxy-containing alcohols, for example in certain polymerization processes.

The object of the present invention was to provide an alternative process for the preparation

(Meth) acrylic acid esters of polyalkoxy-containing alcohols are available with which in particular those (meth) acrylic acid esters are obtained in high purity, which are anhydrous, have a low residual alcohol content and contain only small amounts of catalyst residues. The object is achieved by a process for the preparation of (meth) acrylic esters (E) of polyalkoxy-containing alcohols in which polyalkoxy-containing alcohols (P) of the formula (I)

wherein

Hydrogen, a hydroxy group or a straight-chain or branched, saturated or unsaturated alcohol having 1 to 30 C atoms,

R ² , R ^{3 are} independently H or methyl, and

m, n are independently an integer between 0 and 100, with the proviso that m and n can not be 0 at the same time, in the presence of at least one basic catalyst (K) having a pKa of not more than 7.0 and at least one sterically hindered polymerisation inhibitor having one

Reacting (meth) acrylic anhydride (A), wherein after completion of the reaction, the reaction mixture is quenched with a Ci-C6-alkanol.

With the aid of the process according to the invention, the preparation of (meth) acrylic acid esters (E) of polyalkoxy-containing alcohols with high conversions of the polyalkoxy-containing alcohol (P) is possible. Furthermore, the end product has a low alkali content and a low (meth) acrylic acid content. It is particularly important that the final product is almost anhydrous. Anhydrous in the sense of the present invention means that the water content is below

5 wt .-%, preferably less than 2 wt .-% and particularly preferably less than 1 wt .-%, each based on the final product is.

As the polyalkoxy group-containing alcohols (P), there are usually used those in which R ² and R ^{3 are} independently hydrogen or methyl so that it is an ethylene or propylene oxide unit, particularly preferably an ethylene oxide unit.

Of course, the polyalkoxy-containing alcohol used may contain a plurality of different alkylene oxide units, wherein the alkylene oxide units may be randomly distributed, but may also be arranged in blocks. However, the polyalkoxy-containing alcohols (P) may also contain only one group of alkylene oxide units, preferably ethylene oxide units.

The number m and n of the alkylene oxide units in the polyalkoxy-containing alcohol (P) is usually independently from 1 to 100, in the case of m = 1 and n = 0 or m = 0 and n = 1 is thus a monoalkoxy. Preferably m and n are independently in the range between 5 and 90, particularly preferably between 5 and 50 and particularly preferably between 10 and 50. The substituent R ¹ is hydrogen, a hydroxy group or a straight-chain or branched, saturated or unsaturated alcohol with 1 to 30 carbon atoms. These may be, for example, monoalcohols having 1 to 12 carbon atoms, such as, for example, methanol, ethanol, isopropanol, n-propanol, n-butanol, isobutanol, sec-butanol, tert-butanol, n-hexanol, n-butanol, isobutanol. Heptanol, n-octanol, n-decanol, 2-ethylhexanol, act.

However, the substituent R ¹ is preferably straight-chain, saturated or unsaturated primary alcohols having 6 to 22 carbon atoms, known as fatty alcohols. Such fatty alcohols are, for example, hexan-1-ol (hexyl alcohol, caproic alcohol), heptan-1-ol (heptyl alcohol, eananthalcohol), octan-1-ol (octyl alcohol, capryl alcohol), nonan-1-ol

(Nonyl alcohol, pelargonyl alcohol), decan-1-ol (decyl alcohol, capric alcohol), undecane-1-ol (undecyl alcohol), undec-10-en-1-ol, dodecan-1-ol (dodecyl alcohol, lauryl alcohol), tridecane-1 - ol (tridecyl alcohol), tetradecan-1-ol (tetradecyl alcohol, myristyl alcohol), pentadecan-1-ol (pentadecyl alcohol), hexadecan-1-ol (hexadecyl alcohol, cetyl alcohol, palmityl alcohol), heptadecan-1-ol, heptadecyl alcohol), Octedecan-1-ol (octadecyl alcohol, stearyl alcohol), 9-cis-octadecen-1-ol (oleyl alcohol), 9-trans-octadecen-1-ol (elaidyl alcohol), nonadecan-1-ol (nonadecyl alcohol), eicosane 1 -ol (eicosyl alcohol, arachyl alcohol), 9-cis-eicosene-1-ol (gadoleyl alcohol), heneicosan-1-ol (heneicosyl alcohol), docosan-1-ol (docosyl alcohol, behenyl alcohol), 13-cis-docoses 1-ol (erucyl alcohol), 13-trans-docosen-1-ol (brassidyl alcohol). Of course, mixtures of isomers of these alcohols can be used.

In addition, higher molecular weight alcohols such as lignoceryl alcohol (C24H50O), ceryl alcohol (C26H54O) or myricyl alcohol (C30H62O) can also be used as substituent R ¹ .

However, the abovementioned fatty alcohols having 6 to 22 carbon atoms are preferably used. Preference is given to using fatty alcohols containing 8 to 18, preferably 10 to 16, carbon atoms. These may also be any desired mixtures of fatty alcohols, for example a mixture of fatty alcohols with a C16 and Cis-alkyl chain, with a C13 and Cis-alkyl chain or with a C12 and C30-alkyl chain , For mixtures of fatty alcohols, those with a C16 and Cis-alkyl chain are preferred.

Are usable in the inventive method comprising polyalkoxy alcohol hole sold for example under the trade names Lutensol ^® or Pluriol ^® from BASF SE.

In the reaction step, the reaction is carried out with a (meth) acrylic anhydride (A) in the presence of at least one basic catalyst (K) having a pKa of not more than 7.0.

Suitable catalysts are those having a pKa of not more than 7.0, preferably not more than 5.0, and more preferably not more than 3.0.

In principle, all bases such as alkali metal and alkaline earth metal hydroxides and inorganic salts are suitable. Alkali and alkaline earth metal hydroxides can be dissolved both solid and in solvents, for example, used as aqueous solutions. Inorganic salts which can be used according to the invention are preferably inorganic salts.

Particularly suitable alkali and alkaline earth metal hydroxides are lithium, sodium and potassium hydroxides, and also magnesium and calcium hydroxides. It can also be aqueous solutions of

Sodium, potassium and calcium hydroxide or mixtures or suspensions with sodium, potassium and calcium hydroxide are used. Such aqueous solutions gen / mixtures / suspension contain 10 to 90 wt .-% water, preferably 20 to 80 wt .-% water and particularly preferably 40 to 60 wt .-% water.

The inorganic salt preferably has at least one anion selected from the group consisting of carbonate (CO ³ ^{2 "} ), hydrogen carbonate (HCO ³ ), phosphate (PO 4 ^3" ), hydrogen phosphate (HPO ⁴ ² -), dihydrogen phosphate (H ² PO ⁴ -) , Sulfate (S0 ₄ ² -), sulfite (SO 3 ² -) and carboxylate (R ⁴ - COO-), wherein R ^{4 is} Ci-Cis-alkyl or optionally by one or more oxygen and / or sulfur atoms and / or one or a plurality of substituted or unsubstituted imino groups interrupted C2-Ci8-alkyl or C6-Ci ₄ -aryl.

The collective terms for R ⁴ mentioned in the case of carboxylate (R ¹ -COO-) have the following meaning:

C 1 -C 6 -alkyl: straight-chain or branched hydrocarbon radicals having up to 18 carbon atoms, preferably C 1 -C 10 -alkyl, such as methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, 1, 1-dimethylethyl , Pentyl, 2-methylbutyl, 1, 1-dimethylpropyl, 1, 2-dimethylpropyl, 2,2-dimethylpropyl, 1-ethylpropyl, hexyl, 2-methylpentyl, 3-methylpentyl, 1, 1-dimethylbutyl, 1, 2-dimethylbutyl , 1, 3-dimethylbutyl, 2,2-dimethylbutyl, 2,3-dimethylbutyl, 3,3-dimethylbutyl, 2-ethylbutyl, 1, 1, 2-trimethylpropyl, 1, 2,2-trimethylpropyl, 1-ethyl-1 -methylpropyl, 1-ethyl-2-methylpropyl, heptyl, octyl, 2-ethylhexyl, 2,4,4-trimethylpentyl, 1,1,3,3-tetramethylbutyl, nonyl and decyl and their isomers.

C6-Ci4-aryl: a mono- to trinuclear aromatic ring system containing 6 to 14 carbon ring members, eg. Phenyl, naphthyl and anthracenyl, preferably a mononuclear to dinuclear, more preferably a mononuclear aromatic ring system.

Preferred anions are carbonate, bicarbonate, phosphate, hydrogen phosphate, sulfate, sulfite and carboxylate, particularly preferred are carbonate and phosphate. Phosphate also means the condensation products, such as

Diphosphates, triphosphates and polyphosphates.

The inorganic salt preferably has at least one, more preferably exactly one cation selected from the group consisting of alkali metals, alkaline earth metals, ammonium, cerium, iron, manganese, chromium, molybdenum, cobalt, nickel or zinc.

Preference is given to alkali metals and particular preference to lithium, sodium or potassium.

Particularly preferred inorganic salts are U3PO4, K3PO4, NaßPC, K2CO3 and Na2CÜ3 and their hydrates, most preferably Na2CC "3 and K3PO4. The addition of the inorganic salt can be carried out as a solid, ie as a pure substance, or dissolved in a suitable solvent. Preferably, the salt is added as a solid, with no further component is added to the reaction system, which must be removed consuming.

According to the invention, the polyalkoxy-containing alcohols (P) are reacted with at least one molar equivalent of acrylic anhydride or methacrylic anhydride or a mixture thereof. The term (meth) acrylic anhydride here and hereinafter denotes both acrylic anhydride or methacrylic anhydride and mixtures thereof.

(Meth) acrylic anhydride can also be used in a slight excess, but not 35 mol%, preferably 25 mol%, in particular 15 mol%, and especially 10 mol%, based on 1 mol of polyalkoxy-containing alcohol (P) will exceed, ie the amount of (meth) acrylic anhydride according to the invention is at most 1.35 mol, preferably not more than 1.25 mol, in particular not more than 1.20 mol and especially not more than 1.15 mol per mol of polyalkoxy-containing alcohol (P). Preference is given to using at least 1.005 mol, in particular at least 1.01 mol and more preferably at least 1.02 mol of (meth) acrylic anhydride per mole of polyalkoxy-containing alcohol (P). The reaction of the anhydride with the polyalkoxy-containing alcohol (P) is preferably carried out at temperatures in the range from 0 to 150 ° C., in particular in the range from 20 to 130 ° C. and more preferably in the range from 50 to 100 ° C. The pressure prevailing in the reaction is of minor importance for the success of the reaction and is generally in the range from 800 mbar to 2 bar and often at ambient pressure. The reaction of the anhydride with the polyalkoxy-containing alcohol (P) can be carried out in all conventional apparatuses for such reactions, for. B. in a stirred tank, in stirred tank cascades, autoclaves, tubular reactors or kneaders.

The reaction of the anhydride with the polyalkoxy-containing alcohol (P) is preferably carried out until a conversion of the alcohol (P) used of at least 80%, in particular at least 90% and particularly preferably at least 95% is achieved. The reaction times required for this purpose generally do not exceed 6 hours and are frequently about 4 hours. The conversion can be monitored by ¹ H-NMR spectroscopy of the reaction mixture, preferably by derivatization with trichloroacetyl isocyanate (TAI).

The reaction of the anhydride with the polyalkoxy-containing alcohol (P) can be carried out in bulk, ie without the addition of solvents, or in inert solvents or diluents. Inert solvents are usually aprotic compounds. The inert solvents include, where appropriate, halogenated aromatic hydrocarbons, such as toluene, o-xylene, p-xylene, cumene, chlorobenzene, ethylbenzene, technical mixtures of alkylaromatics, aliphatic and cycloaliphatic hydrocarbons, such as hexane, heptane, octane, isooctane, cyclohexane, cycloheptane, technical Aliphatenmischungen, still ketones such as acetone, methyl ethyl ketone, cyclohexanone, furthermore ethers such as tetrahydrofuran, dioxane, diethyl ether, tert-butyl methyl ether, and mixtures of the abovementioned solvents such. For example, toluene / hexane. Preference is given to working without solvent or only with very small amounts of solvent, generally less than 10% by weight, based on the starting materials, ie in the substance.

The process according to the invention is characterized in particular by the fact that the reaction of the anhydride with the polyalkoxy-containing alcohol (P) can also be carried out in the presence of not insignificant amounts of water. This is advantageous in view of the prior art (e.g., DE 10 2004 042 799 A1), whereafter the water is removed prior to reaction, for example by distillation. However, this is not required by the process according to the invention, so that the reaction mixture may well contain up to 50 mol%, preferably up to 25 mol% and particularly preferably up to 10 mol% of water (based on the alcohol used). The term "reaction mixture" refers to the mixture of the reactants A and P with the base and optionally used solvent and inhibitor.Usually the alcohol used can be the compound P, water, for example up to 0.5% by weight The reaction is usually carried out by reacting the reaction mixture containing the polyalkoxy-containing alcohol (P), the anhydride and the base, the inhibitor and optionally solvent at the temperatures indicated above the alcohol (P), the inhibitor and the base and, if appropriate, the solvent are added and the anhydride is added for this purpose Preferably the addition of the anhydride is carried out at reaction temperature Most preferably, a portion of the anhydride is added before the addition of the base ,

In addition, in order to avoid uncontrolled polymerization, it has proved useful to carry out the reaction of the anhydride with the polyalkoxy-containing alcohol (P) in the presence of a polymerization inhibitor. In the process according to the invention, those polymerization inhibitors which are sterically hindered are used, for example sterically hindered phenols, such as 2,6-di-tert-butylphenol or 2,6-di-tert-butyl-4-methylphenol (butylhydroxytoluene, BHT). and thioazines, such as phenothiazine. Preference is given to using sterically hindered polymerization inhibitors which are not degraded during the course of the reaction, such as, for example, the hydroquinones (hydroquinone, methylhydroquinone) usually employed as polymerization inhibitors. A particularly preferred sterically hindered polymerization inhibitor is 2,6-di-tert-butyl-4-methylphenol (butylhydroxytoluene, BHT). In addition to the previously mentioned sterically hindered polymerization inhibitors, polymerization inhibitors can be added even further to the reaction mixture. Suitable are the known for such reactions polymerization inhibitors, in particular hydroquinone, hydrogen Rochinonmonomethylether (MEHQ), 2,4-dimethyl-6-tert-butylphenol (Topanol A), methylene blue, cerium (III) salts such as cerium (III) acetate and nitroxides, in particular sterically hindered nitroxides, ie nitroxides of secondary amines, the the C atoms which are adjacent to the nitroxide group each carrying 3 alkyl groups, each 2 of these alkyl groups, in particular those which are not on the same carbon atom, with the nitrogen atom of the nitroxide or the carbon atom to which they are attached , form a saturated 5- or 6-membered ring, such as in 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) or 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl ( OH-TEMPO), mixtures of the aforementioned inhibitors, mixtures of the aforementioned inhibitors with oxygen, for. In the form of air, and mixtures of mixtures of the aforementioned inhibitors with oxygen, e.g. B. in the form of air. Preferred polymerization inhibitors from this group are hydroquinone monomethyl ether (MEHQ) and 2,4-dimethyl-6-tert-butylphenol (Topanol A).

The amount of inhibitor may be up to 2% by weight, based on the total amount of anhydride and polyalkoxy group-containing alcohol (P). The inhibitors are advantageously used in amounts of from 10 ppm to 1000 ppm, based on the total amount of anhydride and polyalkoxy-containing alcohol (P). In the case of inhibitor mixtures, this information refers to the total amount of components except oxygen. The reaction of the polyalkoxy-containing alcohol (P) with (meth) acrylic anhydride naturally leads primarily to a mixture of (meth) acrylic esters of polyalkoxy-containing alcohol (P) with acrylic acid or methacrylic acid and optionally residues of excess anhydride and unreacted polyalkoxy-containing alcohol (P ). However, the excess anhydride usually makes no more than 10 wt .-%, and in particular not more than 5 wt .-% of the original amount used

(Meth) acrylic anhydride A from.

Essential to the invention is therefore the separation of the excess anhydride by a quench with a Ci - C6-alkanol, such as methanol, ethanol, propanol, butanol, pentanol and hexanol, and their isomers such as iso-propanol, iso-butanol, tert. Butanol and the isomers of pentanol and hexanol. Preferred C 1 -C 6 -alkanols are methanol, ethanol, propanol and n-butanol, particularly preferred are methanol and ethanol. Of course, it is also possible to use mixtures of the abovementioned C 1 -C 6 -alkanols, but preference is given to using only one of the stated C 1 -C 6 -alkanols.

It is usually cooled after a reaction time of up to 6 h and the Ci - C6-alkanol added. The mixture is then stirred for up to 2 hours, preferably up to 1 hour, but not less than 30 minutes. If required, the excess C 1 -C 6 -alkanol can then be separated off again by customary separation methods, for example by distillation. The C 1 -C 6 -alkanol is added to the reaction medium in amounts of up to 5% by weight, preferably of up to 3% by weight, more preferably of up to 2% by weight and in particular of up to 1% by weight. , in each case based on the total amount of the reaction medium, added. For quenching, however, not less than 0.5% by weight of the C 1 -C 6 -alkanol, based on the total amount of the reaction medium, are added.

The (meth) acrylic esters (E) of polyalkoxy-containing alcohols according to the invention are used, for example, as monomers or comonomers in the preparation of dispersions, for example acrylic dispersions, as reactive diluents, for example in radiation-curable coating compositions or in paints, preferably in exterior paints, and in dispersions For use in paper, cosmetics, pharmaceuticals, agrofuels, textile and oil exploration.

The following examples are intended to illustrate the properties of the invention without, however, limiting it.

Examples

Unless stated otherwise, "parts" or "%" in this document are "parts by weight" or "% by weight".

For the analysis, TAI NMR was used to detect the low residual alcohol content. In this method, the residual alcohol is quantitatively derivatized with trichloroacetyl isocyanate (TAI), and the integrals of the ester signals can be compared. The stabilizer concentrations in the samples were determined by HPLC.

example 1

Preparation of Lutensol ^® AT25 methacrylate with sodium carbonate as a catalyst in a 750 mL plan vessel flask equipped with anchor stirrer (250 rev / min) and attached condenser were 403 g (0.3 mol) of powdered Polyethoxyalkohols (Lutensol by BASF SE ^® AT25, ethoxylation ca. 25, M _w about 1360 g / mol, contained about 0.5 wt .-% water) and melted at a bath temperature of 75 - 100 ° C. At a bottom temperature of 70 ° C., while passing air (3.5 L / h), 184 mg (400 ppm) of butylhydroxytoluene (BHT, 2,6-di-tert-butyl-4-methylphenol) as stabilizer, 56, 6 g (0.345 mol, 94% strength by weight) of methacrylic anhydride which contained 2000 ppm (1 13 mg) of 2,4-dimethyl-6-fe / t-butylphenol (Topanol A) and also 478 mg (1, 5 mol%) of sodium carbonate was added and stirred. The bottom temperature was raised to 90-95 ° C. After 6 hours, the bottom temperature was cooled to 60 ° C and 4.6 g (0.14 mol) of methanol were added. After another hour, the mixture was bottled warm for analysis. The analysis (TAI NMR) shows the following composition: 93.8% Lutensol ^® AT25- methacrylate and 6.2% methacrylic acid. Residual alcohol, methacrylic anhydride and methanol could not be detected in the sample. The stabilizer concentration was determined via HPLC: 360 ppm BHT and <100 ppm Topanol A.

Comparative Examples 1 a - 1 f

Preparation of Lutensol AT25 ^® methacrylate with acidic catalysts and if gegeb Quench with water

The reaction was carried out analogously to Example 1 under the following conditions: bottom temperature 90-95 ° C., molar ratio of alcohol: anhydride 1: 1, 33. The alcohol used contained 22 mol% of water. This work was carried out both without and with different catalysts. In addition, the influence of hydrolysis with water was examined using 27 mol% of water. In the case of hydrolysis, the reaction time was extended by 1 hour. The results are summarized in Table 1.

For better comparability of the values, the liberated methacrylic acid was excluded.

Table 1

On the basis of Comparative Examples 1 a to 1 f it is clear that without catalyst, the conversion is incomplete. The use of catalysts such as PhsP and methanesulfonic also led to incomplete turnover. Both the quenching with water and the water contained in the alcohol did not lead to the hydrolysis of the anhydride.

Examples 2a-2c

Preparation of Lutensol AT25 ^® methacrylate with basic catalysts in a low concentration

The reaction was carried out analogously to Example 1. The reference was a reaction with subsequent quench with water. In all examples, the bottom temperature was 90-94 ° C, the molar ratio of alcohol: anhydride was 1: 1, 1. Quenching with water in the Reference experiment was carried out at a bottom temperature of 100 ° C, the quenching with methanol was carried out at a bottom temperature of 62-63 ° C. The alcohol used contained 0.5% by weight of water. The reaction conditions and results are summarized in Tables 3a and 3b. The resulting methacrylic acid was excluded for better comparability.

- Reaction conditions

Table 2b - Results

Example 3

The reaction was carried out analogously to Example 1. The reference was a reaction without quenching. In both examples, the bottom temperature was 90-93 ° C, the molar ratio of alcohol: anhydride was 1: 1.05. The catalyst used was K3PO4 (1 mol%). The reaction time was 4 hours each. The quenching with ethanol was carried out at a bottom temperature of 78 ° C, the quenching time was 2 hours. The alcohol used contained 0.5% by weight of water. The reaction conditions and results are summarized in Table 4. The resulting methacrylic acid was excluded for better comparability.

Table 3

Despite remaining in the reference experiment residual alcohol content of 5.7 wt .-% is still present hydride, but this reacts completely by the addition of ethanol. The product of Example 3 additionally contains 6.6% ethanol.

Example 4 Preparation of Lutensol ^® AT25-methacrylic acid with sodium carbonate as a catalyst

In a 4 L plan vessel flask equipped with a pitched blade (350 U / min) and baffles and attached condenser were 2016 g (1, 5 mol) of a powdery Polyethoxyalkohols (Luten- _w BASF SE sol ^® AT25, degree of ethoxylation about 25, M approx 1360 g / mol, contained about 0.5 wt .-% water) and melted at a bath temperature of 75 - 100 ° C. At a bottom temperature of 61 ° C while passing air (3.5 L / h) 919 mg (400 ppm) butylhydroxytoluene (BHT, 2,6-di-tert-butyl-4-methylphenol) as a stabilizer, 283 g (1, 725 mol, 94 wt .-%) of methacrylic anhydride, which contained 2000 ppm (566 mg) of 2,4-dimethyl-6-fe / t-butylphenol (Topanol A), and 2.39 g (1, 5 mol%) sodium carbonate was added and stirred. The bottom temperature was raised to 90-95 ° C. After 6 hours, the bottom temperature was cooled to 60 ° C and 23 g (0.72 mol) of methanol were added. After a further hour, pure methacrylic acid (stabilized with 200 ppm MEHQ) was added to the mixture and adjusted to a methacrylic acid content of 50% by weight and filled up for the analysis.

The analysis (TAI NMR) showed over the course of the reaction the composition summarized in Table 4:

Table 4

The course of the reaction shows that after 4 hours only 0.7% by weight and after 6 hours only 0.1% by weight of anhydride is present in the reaction mixture. After quenching with methanol, the anhydride is completely reacted.

Example 5

Preparation of Lutensol ^® AT25-methacrylic esters with aqueous sodium hydroxide solution as a catalyst in a 750 mL plan vessel flask equipped with a pitched blade (350 U / min) and baffles and attached condenser were 403 g (0.3 mol) of powdered Polyethoxyalkohols (Lutensol from BASF ^® AT25 SE, degree of ethoxylation about 25, M _w about 1360 g / mol, contained about 0.5 wt .-% water) and melted at a bath temperature of 75 - 100 ° C. At a bottom temperature of 68 ° C., while passing air (3.5 L / h), 184 mg (400 ppm) of butylhydroxytoluene (BHT, 2,6-di-tert-butyl-4-methylphenol) as stabilizer, 56, 6 g (0.345 mol, 94% strength by weight) of methacrylic anhydride which contains 2000 ppm (13 mg) of 2,4-dimethyl-6-Fe / t butylphenol (Topanol A), and 50 wt .-% (0.36 g, 1, 5 mol%) of aqueous sodium hydroxide solution was added and stirred. The bottom temperature was raised to 90-95 ° C. After 6 hours, the bottom temperature was cooled to 60 ° C and 4.6 g (0.14 mol) of methanol were added. After another hour, the mixture was bottled warm for the analysis.

The analysis (TAI NMR) showed the composition summarized in Table 6 over the course of the reaction: TABLE 5

Surprisingly, the use of aqueous sodium hydroxide solution as catalyst shows that this did not lead to the hydrolysis of the anhydride but still complete conversion of the alcohol.

Example 6

Preparation of Lutensol ^® AT25-methacrylic esters with subsequent addition of aqueous sodium hydroxide solution as a catalyst in a 750 mL plan vessel flask equipped with a pitched blade (500 U / min) and baffles and attached condenser, 605 g (0.45 mol) of powdered Polyethoxyalkohols (Lutensol ^® AT25 of BASF SE, degree of ethoxylation about 25, M _w about 1360 g / mol, contained about 0.15% by weight of water) and melted at a bath temperature of 75 - 100 ° C. At a bottom temperature of 76 ° C., while passing air (3.5 L / h), 276 mg (400 ppm) of butylhydroxytoluene (BHT, 2,6-di-tert-butyl-4-methylphenol) as stabilizer, 66, 5 g (0.405 mol, 94 wt .-%) of methacrylic anhydride, which contained 2000 ppm of 2,4-dimethyl-6-Fe / t-butylphenol (Topanol A) added and stirred. The bottom temperature was raised to 90-95 ° C. After 30 minutes, an additional 14.8 g (0.09 mol) of methacrylic anhydride and 50% strength by weight (0.72 g, 2 mol%) of aqueous sodium hydroxide solution were added. After 6 hours, the bottom temperature was cooled to 55 ° C and 10.4 g (0.32 mol) of methanol were added. After another hour, the mixture was bottled warm for the analysis.

The analysis (TAI NMR) showed over the course of the reaction the composition summarized in Table 7:

Table 6 Sample product residual alcohol anhydride methacrylic acid methanol [%]

[%] [%] [%] [%]

after 4.5 h 92.6 1, 0 0.5 6.0 0

after 6 h 93.5 0 0.4 6.0 0

after 1 h 93.7 0 0 5.9 0.4

quench

Example 7

Preparation of Lutensol AT25 ^® methacrylate, influence of polymerization inhibitors in a 750 mL flask plan vessel with anchor stirrer (350 rev / min) and attached condenser 252.6 g (0.19 mol) of powdered Polyethoxyalkohols (Lutensol AT25 from BASF SE ^®, ethoxylation about 25, M _w about 1360 g / mol, contained about 0.15 wt .-% water) and melted at a bath temperature of 75 - 100 ° C. While passing air (3.5 L / h) 210 mg (730 ppm) of methylhydroquinone monomethyl ether (MEHQ) as stabilizer, 34.8 g (0.21 mol, 94 wt .-%) of methacrylic anhydride, which 2000 ppm 2 , 4-dimethyl-6-Fe / t-butylphenol (Topanol A) was added and stirred. The bottom temperature was raised to 90-95 ° C. After the end of the reaction, the mixture was cooled to room temperature and the onset temperature of the polymerization was determined. The reaction mixture polymerized on remelting at a bath temperature of 85 ° C.

Analogous experiments were carried out with MEHQ and BHT as stabilizer, the results are summarized in Table 7.

Table 7

Examination of the onset of polymerization revealed that they change during the reaction when MEHQ is used. However, when a hindered polymerization inhibitor such as BHT is used, the onset remains stable. The reaction mixtures could be remelted without polymerizing.

Example 8

Reacting Lutensol ^® AT 1 1 with methacrylic anhydride, and sodium carbonate as the catalyst in a 1, 6L plan vessel flask equipped with anchor stirrer and baffles (220 U / min) and attached condenser 1018 g Lutensol ^® AT 1 1 (1, 4 mol) were charged and at 75 - 100 ° C bath temp. melted down. At a bottom temperature of 74 ° C, 507 mg BHT (400 ppm), 248 g Methacrylsäureanhyrid (1, 6 mol, 94%, containing 2000 ppm Topanol A) and Na2C03 (2.07 g, 1, 5 mol%) were added while passing air (3.5 L / h). The bottom temperature was raised to 90-95 ° C.

After 6 h, the bottom temperature was cooled to 75 ° C. and methanol (38 g, 2% by weight) was metered in. After 1 h, the mixture was adjusted to a methacrylic acid content of 40% with methacrylic acid (MAS, pure, stabilized with 200 ppm MEHQ) and cooled.

The samples (TAI-NMR) show the following composition:

Example 9

(220 U / min) Reaction of Lutensol ^® AT 50 with methacrylic anhydride, and sodium carbonate as the catalyst in a 1, 6L plan vessel flask equipped with anchor stirrer and baffles and attached condenser were placed 1 125 g Lutensol ^® AT 1 1 (0.46 mol) and 75 - Melted at 100 ° C bath temperature. At a bottom temperature of 65 ° C., 484 mg of BHT (400 ppm), 86.4 g of methacrylic anhydride (0.53 mol, 94%, containing 2000 ppm of Topanol A) and Na 2 CO 3 (0.73 g, 1, 5 mol%) were used. ) metered while passing air (3.5 L / h). The bottom temperature was raised to 90-95 ° C.

After 6 h, the bottom temperature was cooled to 66 ° C. and methanol (36 g) was added. After 1 h, the mixture was adjusted to a methacrylic acid content of 45% with methacrylic acid (MAS, pure, stabilized with 200 ppm MEHQ) and cooled.

The samples (TAI-NMR) show the following composition:

Example 10

Reacting Emulgin ^® BA 25 with methacrylic anhydride and sodium hydroxide as a catalyst In a 0.75L flask plan vessel with inclined blade (500 U / min) and attached condenser were 837 g Emulgin ^® BA 25 (0.6 mol, enthlatend 0.22% water) were charged and melted bath temperature at 85 ° C. At a bottom temperature of 68 ° C., 380 mg of BHT (400 ppm), 88.5 g of methacrylic anhydride (0.54 mol, 94%, containing 2000 ppm of Topanol A) and aqueous NaOH (50%, 0.96 g, 2 mol%) metered in while passing air (3.5 L / h). After 30 minutes, an additional 19.7 g of methacrylic anhydride (0.12 mol) were metered in, and the bottom temperature was raised to 90-95.degree.

After 6 h, the bottom temperature was cooled to 61 ° C. and methanol (1 l, 4 g) was added. After 1 h, the mixture was bottled hot.

The samples (TAI-NMR) show the following composition:

Example 1 1

Reaction of Pluriol ^® A2010E with methacrylic anhydride and sodium hydroxide as catalyst

In a 1, 6L plan vessel flask equipped with anchor stirrer (220 rev / min) and attached condenser, 1000 g of Pluriol A2010E ^® (0.5 mol, containing 0.21% water) were charged and melted bath temperature at 100 ° C. At a bottom temperature of 94 ° C., 438 mg of BHT (400 ppm), 73.8 g of methacrylic acid anhyride (0.45 mol, 94% strength, containing 2000 ppm of Topanol A) and aqueous NaOH (50% strength, 0.8 g, 1.5 mol%) while passing in air (3.5 L / h). After 30 minutes, an additional 20.5 g of methacrylic anhydride (0.13 mol) were added.

After 6 h, the bottom temperature was cooled to 68 ° C. and methanol (10 g) was added. After 30 minutes, 975 g of methacrylic acid were added to the mixture and the product was bottled.

The samples (TAI-NMR) show the following composition:

Sample Pluriol A2010E ^® anhydride [wt ester [wt .-%] MAS [wt .-%]

[% By weight]%]

after 6 h 0 0.6 94.8 4.7

after 30 min 0 0 95.4 4.6

quench

Claims

claims

Process for the preparation of (meth) acrylic acid esters (E) of polyalkoxy-containing alcohols, in which polyalkoxy-containing alcohols (P) of the formula (I)

wherein

R ^{1 is} hydrogen, a hydroxy group or a straight-chain or branched,

saturated or unsaturated alcohol having 1 to 30 carbon atoms,

R ² , R ^{3 are} independently H or methyl, and

m, n are independently an integer between 0 and 100, with the proviso that m and n can not be simultaneously 0, in the presence of at least one basic catalyst (K) having a pKa of not more than 7.0 and at least one sterically hindered Polymerisationsinhibtors with a (meth) acrylic anhydride (A), wherein after completion of the reaction, the reaction mixture is quenched with a Ci-C6-alkanol.

A method according to claim 1, characterized in that in the formula (I) R ² and R ^{3 is} hydrogen.

Method according to one of the preceding claims, characterized in that in the formula (I) m and n are independently integers in the range of 5 to 90.

A method according to claim 3, characterized in that in the formula (I) m and n are independently integers in the range of 5 to 50.

Process according to any one of the preceding claims, characterized in that the substituent R ^{1 is} a straight-chained, saturated or unsaturated primary alcohol having 6 to 22 carbon atoms.

Process according to any one of the preceding claims, characterized in that the basic catalyst (K) has a pKa of not more than 3.0.

7. The method according to claim 6, characterized in that the basic catalyst is selected from the group of alkali and alkaline earth metal hydroxides and inorganic salts.

Process according to claim 7, characterized in that the basic catalyst is lithium, sodium and potassium hydroxide or magnesium and calcium hydroxide.

A method according to claim 7, characterized in that the inorganic salt is at least one anion selected from the group consisting of carbonate (CO3 ^{2 "} ), hydrogen gencarbonat (HCO ^3- ), phosphate (PO4 ^3" ), hydrogen phosphate (HPO4 ^{2 "} ) , Dihydrogen phosphate (H ² PO ⁴ -), sulfate (S0 ₄ ² -), sulfite (SO 3 ² -) and carboxylate (R ⁴ -COO-), where R ^{4 is} C 1 -C 18 -alkyl or optionally substituted by one or more oxygen atoms. and / or sulfur atoms and / or one or more substituted or unsubstituted imino groups, C2-CI8-alkyl or C6-Ci ₄ represents aryl having.

10. The method according to claim 9, characterized in that the inorganic salt is selected from the group U3PO4, K3PO4, Na3P0 ₄ , K2CO3 and Na2CÜ3 and their hydrates.

1 1. The method according to any one of the preceding claims, characterized in that the amount of meth) acrylic acid anhydride (A) is used at most 1, 35 moles per mole of polyalkoxy-containing alcohol (P). 12. The method according to claim 11, characterized in that the amount of

Meth) acrylic anhydride (A) at most 1, 15 moles per mole of polyalkoxy-containing alcohol (P) is used.

13. The method according to any one of the preceding claims, characterized in that the sterically hindered polymerization inhibitor is not degraded during the course of the reaction.

14. The method according to claim 13, characterized in that the sterically hindered polymerization inhibitor is selected from the group consisting of 2,6-di-tert-butylphenol, 2,6-di-tert-butyl-4-methylphenol and phenothiazine.

15. The method according to any one of the preceding claims, characterized in that the C1 - C6-alkanol is selected from the group consisting of methanol, ethanol, propanol and iso-propanol.

16. The method according to claim 15, characterized in that the C1 - C6 alkanol is selected from methanol and ethanol.

17. The method according to any one of the preceding claims, characterized in that the quenching time is up to 2 h, but not less than 30 minutes. 18. The method according to any one of the preceding claims, characterized in that the Ci - C6-alkanol is added to the reaction medium in amounts of up to 5 wt .-%, based on the total amount of the reaction medium.

19. Use of meth) acrylic esters (E) of polyalkoxy-containing alcohols as monomers or comonomers in the preparation of dispersions, for example

Acrylic dispersions, as reactive diluents, for example in radiation-curable coating compositions or in paints, and in dispersions for use in the paper sector, in the cosmetics sector, in the pharmaceutical sector, in agricultural formulations, in the textile industry and in the field of oil extraction.