NO171682B - REACTION BLENDS CONTAINING COPOLYMERS OF HYDROPHOBE ACRYLIC RESP. METACRYLIC ACID ESTERS AND HYDROPHILIC COMMONOMERS, PREPARING AND USING THEREOF - Google Patents

Description

The invention relates to reaction mixtures containing copolymers which are based on hydrophobic acrylic acid or methacrylic acid esters, a method for the preparation of these reaction mixtures and their use as crude oil emulsion splitters for rapid dewatering of crude oils.

After an initial phase where practically pure crude oil is extracted, the largest part of the produced crude oil appears as water-in-oil emulsions.

The water must be separated before transport, or its concentration must be lowered below an acceptable level. This is mostly done by adding so-called crude oil emulsion splitters, whereby heating the crude oil facilitates and accelerates the split-up. The composition of the crude oil varies greatly with the place of extraction. To achieve optimal de-emulsification results, many different crude oil emulsion splitters are therefore used around the world. There is, however, a great interest in de-emulsifiers which, in the case of various crude oil emulsions, provide faster splitting in water in oil and also good amounts of residual water and residual salt.

The most frequently used de-emulsifiers are ethylene oxide/propylene oxide block polymers, alkoxylated alkylphenol-formaldehyde resins, alkylated polyamines and especially cross-linking products of the above-mentioned basic classes with multifunctional reagents such as diisocyanates, dicarboxylic acids, bisglycidyl ethers, di- and trimethylolphenol.

Polymeric petroleum emulsion separators are also known (Canadian Patent No. 1,010,740 and DE-C1 33 38 923).

According to this Canadian patent, unsaturated radical polymerizable functions are introduced into alkylated alcohols and alkylphenol-formaldehyde resins by etherification with unsaturated glycidyl compounds (e.g. glycidyl acrylate), by esterification with maleic anhydride or fumaric acid or by transesterification with acrylic esters or methacrylic esters, which are then polymerized by a subsequent reaction with other monomers in solution. DE-C1 33 38 923 describes products obtained by copolymerization of polyoxyalkylene ethers of allyl or methallyl alcohols with vinyl esters or

acrylic or methacrylic acid esters.

All of these products exhibit performance-specific or manufacturing-related weaknesses. When using glycidyl compounds to introduce the unsaturated function, the polymerization often results in the formation of gel bodies and inhomogeneities, when using allyl alcohol, metallyl alcohol and maleic acid, poor copolymerization conditions are obtained and when the transesterification with acrylic acid esters or methacrylic acid esters results in a difficult development of the complete and selective esterification of the partially polyfunctional starting alcohol alcohol.

Furthermore, when the copolymers are stored, gelation and solidification reactions will often occur, especially when using the multifunctional starting alcohol during the alkylation. Products with high action potential and a broad spectrum of applications can, however, already be obtained by using alkylated polyfunctional alcohols.

It has now surprisingly been found that copolymers suitable as petroleum emulsion breakers formed from hydrophobic acrylic acid or methacrylic acid esters, whose alcohol components derive from a mixture of polyglycols and polyglycol ethers, with hydrophilic ethylenically unsaturated comonomers, become storage stable and have an increased effect when in this copolymer (i) all or almost all free OH groups are etherified, esterified or transferred in a urethane grouping, and/or (ii) the acid used as a catalyst in the esterification is neutralized by amine addition. Incidentally, reference is made to requirement 1.

The method for producing the reaction mixtures according to the invention and the use of the aforementioned reaction mixtures are described respectively in claims 6 and 8.

The mixture of polyalkylene glycols and polyalkylene glycol ethers used for esterification usually consists of alkoxylates with

the formula

where R<1> means a residue of a monohydric or polyhydric alcohol or alkylphenol or a residue of an alkylphenol/formaldehyde or alkylphenol/acetaldehyde condensation product, AO is an ethylene-

oxide, propylene oxide or 1,2-butylene oxide residue or mixtures of these residues or blocks of these residues, and x means a number from 5 to 120.

The object of the invention is thus in particular reaction mixtures of copolymers where

A) acrylic acid ester or methacrylic acid ester with alkoxylates with

the formula

where R<1>, AO and x have the meanings given above, is

copolymerized with

B) hydrophilic copolymers of the formula

where

R<2> means hydrogen or a residue -COOH, -COOC2H4OH, -COOC2 H4 N (C2 Hs ) 2 , -CONH2 , -CN, , -OCOCH3 , -CH2 OH, -NHCHO, -COOCH3 , -COOC2 H5 , or

R<3> means hydrogen or -COOH, and

RA means hydrogen or -CH3,

under the condition that at least one of the groups R<2> or R<3> is a hydrophilic group,

whereby the weight ratio between A) and B) is 3 00:1 to 1:50

and whereby

C) the free OH groups have been transferred by etherification, esterification or urethane formation to a no longer reactive form,

and or

that the acid used as a catalyst in the preparation of the ester at A) and/or the esterification at C) is neutralized with a tertiary amine.

The conversion of the free OH groups can also take place before the polymerization and even partially before the preparation of the ester comonomer.

The copolymers are produced in a manner known per se, e.g. by radical copolymerization in solution, emulsion or suspension.

The esterification of the acrylic acid or methacrylic acid preferably takes place in the presence of acidic esterification catalysts and using drawing agents.

Common inorganic or organic catalysts such as sulfuric acid, p-toluenesulfonic acid, dodecylbenzenesulfonic acid, hydrochloric acid or acidic ion exchangers can be used as acid esterification catalysts.

Organic solvents which usually form an azeotrope with water, especially xylene or toluene, can be mentioned as drawing agents.

Agents such as, for example, methyl iodide, dimethyl sulfate or benzyl chloride can be used for etherification of the free OH groups.

Carboxylic anhydrides such as acetic anhydride, maleic anhydride or succinic anhydride are preferably used for esterification of the free OH groups.

The transfer of the free OH groups to a urethane grouping, i.e. the preferred reaction after the copolymerization conveniently takes place by the action of isocyanates in a manner known per se, e.g. with phenyl isocyanate or stearyl isocyanate.

To neutralize the acids used as esterification catalyst, amines are used, preferably tertiary amines. In the individual cases, for example, triethylamine, tributylamine, dimethyl-Cy-amine (y = C8-C18) or triethanolamine are used.

In more detail, for example, the production of the new polymers takes place as follows:

Preparation of Alkoxylates with the formula F^-O-tAOj-H

a) Preparation of the alkoxylated alcohols

The production of the alkoxylated alcohols takes place on

known way by reacting the mono- or polyfunctional alcohols with an alkoxide or a mixture of several alkoxides or blockwise with several alkoxides using basic catalysts at temperatures from 80 to 160°C. As alcohols, it can e.g. ethanol, butanol, isopropanol, tallow fat are used

alcohol, stearyl alcohol, alkylphenols of the general formula

where R e.g. is C9H19, CH3, CH(CH3)2, C(CH3)3 or C8H17, ethylene glycol, propylene glycol, bisphenol A, glycerol, trimethylolpropane, pentaerythritol, sorbitol, polyglycerol or the alkylphenol/formaldehyde resp. described below. acetaldehyde condensation products.

Preferred alkoxides are propylene oxide and 1,2-butylene oxide or mixtures thereof where ethylene oxide may also be present.

The reaction conditions vary according to the nature and quantity of the alkoxides used. The reaction temperature is usually between 80 and 160°C and the amount of basic catalysts varies between 0.25 and 5%, and here potassium hydroxide and sodium hydroxide are preferred. Depending on the consistency of the starting alcohol or an inert solvent can be added as a dilution to the end product, which does not affect the turnover. Xylene is preferred.

The ratio between alcohol and alkoxide(s) can vary greatly, but it is suitably in the range from 1:120 to 1:5.

b) Alkoxylated alkylphenol/formaldehyde or acetaldehyde condensation products

Those who used alkylphenol/formaldehyde resp. Acetaldehyde resins can be prepared in a known manner by reacting the aldehyde with the alkylphenol in a ratio of 2:1 to 1:2, preferably 1:1.05, with base or acid catalysis, preferably acid catalysis, at temperatures from 80 to 250°C by means of a high-boiling solvent for complete azeotropic removal of the water of reaction formed. Nonylphenol, t-butylphenol or octylphenol are used as alkylphenols, for example, and formaldehyde and acetaldehyde are preferably used as aldehydes. An alkylsulphonic acid or alkylbenzenesulphonic acid is usually used as a catalyst, e.g. .eg dodecylbenzenesulfonic acid in an amount of 0.2 to 2%, preferably 0.2 to 0.5%.

At the beginning of the reaction, the temperature is maintained at 90 to 120°C, until the majority of the reaction water is distilled off. Then, in order to achieve complete reaction, it is heated up to the boiling point of the solvent, and the remaining amount of water is removed azeotropically. On average, the molecule contains 4 to 12 aromatic cores, preferably 5 to 9.

The condensation products thus obtained are alkylated as indicated under a).

c) Partial reaction of the free OH groups in the alkoxylates from a) and b)

After the carboxylation has been completed, the alkoxylates from steps a) or b) can partially have the end groups closed, and it is preferred to have an end group closure of 20 to 90% of the OH groups. The closing of terminal hydroxyl groups can take place by acid-catalyzed esterification with carboxylic acid anhydrides, preferably acetic anhydride, succinic anhydride and maleic anhydride, at temperatures from 50 to 130°C, or by reacting the alcoholates with dimethyl sulphate, benzyl chloride and methyl iodide, this being the addition of an alkylating agent to sodium or potassium alcoholates takes place at temperatures from 40 to 80°C, and by reaction with isocyanates.

A) Conversion of the alkoxylates to unsaturated monomers

Since the de-emulsifiers for crude oil emulsions must be surfactants, the magnitude of the hydrophilicity resp. the hydrophobicity set by the ratio of polyethylene oxide block (hydrophilic) to polypropylene block (hydrophobic) to hydrophilic comonomers (e.g. acrylic acid). Since these products must be soluble in crude oil for maximum effect, it is important that the hydrophilic polyacrylic acid portion of the copolymer is kept dissolved in an aromatic solvent (e.g. toluene, xylene or aromatic mixture) by a large hydrophobic residue. This is only achieved by the complete and selective introduction of a radically polymerisable functionality in the hydrophobic, alkylated, possibly end-group-closed alcohol, and its use in the subsequent radical copolymerization with hydrophilic comonomers.

To introduce the unsaturated functionality into the alkylated, possibly partially end-group-closed alcohol, this is esterified in the presence of acid catalysts (e.g. p-toluenesulfonic acid, sulfuric acid or dodecylbenzenesulfonic acid) at temperatures from 80 to 150°C with acrylic acid or methacrylic acid, whereby the necessary complete removal of the reaction water is carried out with an azeotropic drawing agent, preferably toluene or xylene.

To prevent polymerization during the esterification, it is recommended to add known stabilizers (preferably hydroquinone monomethyl ether). The ratio between alkoxylated alcohol and acrylic acid resp. Methacrylic acid can vary between 1:1 and 1:n, where n means the functionality (i.e. the number of hydroxyl groups) of the starting alcohol. A ratio of 1:1 is preferred, as gelation can otherwise be observed during the subsequent polymerization. The complete esterification of the acrylic acid or the methacrylic acid is appropriately determined by analytical methods (e.g. acid number). The amount of stabilizer is varied between 0.3 and 2% by weight, preferably 1% by weight, based on the amount of acrylic acid or methacrylic acid. The acid catalyst is added in amounts of 0.5 to 5% by weight, preferably 2 to 3% by weight. Equally good esterification results are obtained by using acrylic acid anhydride or methacrylic anhydride and acrylic acid chloride resp. methacrylic acid chloride. In this case, the separation of water takes place by azeotropic distillation.

The weight ratio of solvent to the sum of oxalkylated alcohol and unsaturated carboxylic acid can vary between 30:70 and 70:30, and it is preferred with a ratio of 50:50 to 30:70.

After esterification with acrylic acid or Methacrylic acid can be closed with carboxylic acid anhydrides and isocyanates if the existing hydroxyl functions are closed. Phthalic anhydride, acetic anhydride and maleic anhydride are preferred. Thereby, all the hydroxyl groups can be closed by adding equimolar amounts of anhydrides, alkylating agents or isocyanates, or only partial closing can be carried out. It is preferred to have a conversion of 70 to 100% of the terminal hydroxyl groups present. The anhydride or isocyanates are added to the solution of acrylic or the methacrylic acid ester, optionally in the presence of a catalyst, and the reaction is terminated accordingly

the reactivity within 0.5 to 5 hours at 70 to 120°C.

After esterification has been completed, the added catalytic acid can be neutralized by adding equimolecular amounts of amines, e.g. triethanolamine, triethylamine or tributylamine. However, it is preferred to neutralize the acid after completed polymerization and possibly condensation.

B) Copolymerization of the alkoxylate ester monomers from A) with hydrophilic comonomers

The preparation of the copolymers can take place by solution, emulsion or precipitation polymerization, and solution polymerization in a non-polar solvent (such as toluene or xylene) is preferred. For the solution of the esterified, possibly end-group-closed, alkylated alcohol, resp. a mixture of several different optionally end-group-closed, alkoxylated alcohols from A), is added or added dropwise to the comonomer resp. a mixture of several comonomers, and the reaction can be carried out with the help of known radical initiators at temperatures from 60 to 140°C. Typical comonomers are: acrylic acid, methacrylic acid, maleic anhydride, hydroxyethyl acrylate, N,N-diethylaminomethylacrylate, acrylamide, acrylonitrile, vinyl acetate, allyl alcohol, vinylformamide, vinylimidazole, vinylpyrrolidone, fumaric acid, maleic acid, N,N-dimethylacrylamide or vinyl methyl ether, whereby acrylic acid, optionally in a mixture with other comonomers in a ratio of 10:1 to 1:1, is preferred.

As a rule, 2,2-azo-bis-iso-butyronitrile (AIBN), dibenzoyl peroxide, t-butyl peracetate or 2,2-azo-bis-2,4-dimethylvaleronitrile are used as radical initiators, and AIBN and dibenzoyl peroxide are preferred. The amount of radical initiator used is usually between 0.1 and 2% by weight, based on the overall monomer content. In order to achieve as low a residual monomer concentration as possible, a reaction duration of 5 times the half-life of the initiator at the selected reaction temperature is recommended. By adding the radical initiator drop by drop, possibly in the presence of known molecular weight regulating substances, such as mercaptans or aldehydes, possibly also by simultaneously adding (part of) the comonomers, the exothermic copolymerization can be optimized with regard to heat tinting, molecular weight distribution and residual monomer content. It is preferred with a one-time initial addition of 0.1 to 0.8 wt% AIBN to dissolve the ester and comonomers and with polymerization at 60 to 90°C during 2 to 5 hours and also continuous addition of AIBN to the solution of ester and comonomers (optionally after initial addition of AIBN to the solution) during 0.5 to 3 hours at temperatures from 60 to 90°C, optionally in the presence of molecular weight-regulating compounds such as mercaptans and aldehydes in amounts of from 0 .05 to 1% by weight, based on the comonomers. Possible, but not preferred, is also the simultaneous use of several esterified, possibly end-group-closed, alkylated alcohols and also the addition or dosing of several comonomers. The polymerization concentration is between 20 and 70% by weight, and 40 - 60% by weight is preferred. In order to obtain highly effective products, it is often recommended to pre-polymerize the hydrophobic, possibly end-group-closed ester of alkylated alcohol and acrylic acid or methacrylic acid over the course of 1 to 2 hours with the aforementioned radical initiator and a subsequent addition or continuous dosing of the comonomers over 1/3 to 2/3 of the reaction time, optionally with further radical initiator.

The K value of the polymers obtained is usually 15 to 60 (measured in 1% xylene solution). To influence the molecular weight, common chain regulators such as aldehydes or thio compounds (eg thioethanol, thioglycolic acid) can be added. Cross-linking difunctional comonomers such as methylene bisacrylamide can also be used to increase the molecular weight.

C) End-group closure and/or neutralization of the catalytic acid quantities after completion of polymerization

In order to increase the efficiency and especially the increase in the storage stability of the copolymers, partial intramolecular esterification is carried out after completed polymerization or a completed closure of still free hydroxyl functions by means of reaction with anhydrides or isocyanates and/or neutralization of still present catalytic acid amounts with amines to avoid transesterification reactions, which can lead to gelation of the products.

A partial intramolecular condensation is achieved by heating the polymerization solution from B) to temperatures from 100 to 140°C for a period of 1 to 5 hours. A 2-hour heating of the xylenic polymerization solution from B) from 110 to 120°C is preferred. In case of secondary condensation, gel formation may occur.

The reaction of the free OH groups with anhydrides and isocyanates can be carried out directly after the polymerization or after partial intramolecular condensation, whereby a partial closure of the hydroxyl groups present after the polymerization and subsequent condensation with azeotropic drawing agents during water extraction can also take place. It is preferred with complete end-group closure after partial intramolecular condensation at 110 to 120°C and/or closure of 60 to 80% of the hydroxyl groups present directly after polymerization with subsequent condensation by azeotropic extrusion of the reaction water using a drawing agent, preferably xylene .

The end group closure is achieved by adding or dosing the desired amount of anhydride or isocyanate to the polymerization solution and heating to 70 - 120°C within 0.5 - 5 hours, possibly in the presence of catalysts known per se. Preferred as an esterification agent are acetic anhydride, phthalic anhydride and succinic anhydride.

If the end group closure already takes place at the step with the alkoxylate or the hydrophobic acrylic acid or methacrylic acid ester, it is preferred to condense after the polymerization with the aid of an azeotropic drawing agent.

In addition to or alternatively to the end-group closure, there is continued neutralization of still present catalytic amounts of acid from the esterification step with amines. The neutralization is preferably carried out after completion of polymerization, whereby further esterification reactions, which can lead to gel formation, are prevented.

The neutralization of the still present traces of catalytic acid from the esterification reaction takes place by adding equimolecular amounts of amines, e.g. triethanolamine, tributylamine or triethylamine, to the solution of the optionally end-group-closed polymers and reaction at temperatures from 20 to 80°C during 2 hours. The complete neutralization can be carried out using the amine number.

D) Modification of the polymers from B) and C) (optional)

In order to increase the efficiency and to adjust for the crude oil to be treated each time, it may possibly make sense with a supplementary modification of the copolymers obtained under B) and C). Depending on the comonomers used during the copolymerization, the following changes can be made to the product: 1) Mixing with an alkylated alcohol or a mixture of several alkylated alcohols, e.g. such as described, obtained under b), or with other copolymers from B) and C) in the ratio 10:90 to 90:10, and preferably 50:50 to 80:20.

Better efficiency can also be achieved by adding so-called co-surfactants to the copolymers in amounts from 5 to 30% by weight. Such co-surfactants can e.g. be dodecyl hydrogen sulfate, alkyl benzene sulfonate or alkyl naphthalene sulfonate. 2) An increase in molecular weight can be achieved by supplementary cross-linking with multifunctional coupling agents, which react with reactive groups on the copolymers.

In this way, the cross-linking (depending on the type of cross-linking agent) is carried out with 0.1 to 10% by weight, preferably 1-4% by weight, of the multifunctional components at temperatures from 80 to 140°C. As multifunctional cross-linking agents, depending on the comonomers used, bisglycidyl ethers (preferably bisglycidyl ethers of bisphenol A), multifunctional alcohols (e.g. sorbitol, ethylene glycol), diisocyanates (e.g. toluene diisocyanate) and comparable compounds are used, which are reacted with reactive places on

the copolymers.

3) Post-alkylation with an alkoxide, a mixture of several alkoxides or blockwise with different alkoxides. Thus, the copolymers from B) and C) are reacted with basic catalysts (sodium hydroxide and potassium hydroxide are preferred) in amounts from 0.5 to 5% by weight at temperatures from 100 to 150°C with the alkoxide(s). Ethylene oxide, propylene oxide or 1,2-butylene oxide are preferably used as alkoxide, whereby the ratio between copolymer

and alkoxide varies between 5:95 and 95:5.

4) Quaternization of N-containing copolymers with known quaternization agents, such as dimethyl sulfate or methyl iodide at temperatures from 50 to 120°C. Thereby, a complete or only partial quaternization of the amine functions present can be carried out.

There is no limitation to any particular application of a modification to the copolymer from C). On the other hand, optional changes can be made in accordance with 1) to 4) one after the other.

Example

a) Preparation of the alkoxylated alcohols (alkoxylates)

31 g are introduced into an autoclave under a nitrogen atmosphere

trimethylolpropane and 0.3 g of potassium hydroxide and the mixture is reacted at 130 to 140°C and 6 bar with 800 g of propylene oxide within 10 hours. Then, in another step at 120 to 130°C, a further 101 g of ethylene oxide is added. Towards the end of the reaction, the temperature is kept for 1 hour at 140°C in order to achieve complete reaction if possible. The molecular weight is calculated from the measured OH number to 3820. This is e.g. a5 in the following table. To simplify, detailed description of the further examples is waived. However, the reaction conditions are largely consistent with those indicated in the above example. In the reaction with mixed oxides, the alkoxide used each time is mixed into a premix and is then dosed.

b) Production of alkylphenol/formaldehyde resp. acetaldehyde resins

119 g of xylene is added to 440 g of nonylphenol and at 40°C 60 g of para-formaldehyde is added. Then, at 35°C, 1.5 g of dodecylbenzenesulfonic acid is added, after which an exothermic condensation begins. During cooling, the reaction temperature is maintained for 3 hours at 65-70°C. The material is then heated for 2 hours at 90°C. In order to make the reaction complete, it is heated for 4 hours at from 95 to 100°C, whereby the material is distilled under reflux. The reaction water is then distilled off and, for complete dewatering, water is removed azeotropically with xylene for 6 hours. After cooling, the nonylphenol/formaldehyde resin is obtained as a medium viscosity 75 to 80% solution in xylene. This is e.g. bl in the following table.

c) End group closure of the alkoxylates from a) and b)

200 g of the alkoxylate from e.g. a 15 is mixed with 8 g of

50% sodium hydroxide solution and the alcoholate are prepared under reduced pressure at 100-170°C.

Then, at 50-55°C, 12.6 g of dimethylsulphate solution is added drop by drop and after the addition is complete, a sample is taken for free dimethylsulphate. If necessary, it is left to react at 60-70°C, until the test for free dimethylsulphate shows a negative result. This is, for example, c 1.

A) Preparation of the alkoxylated ester monomers

1) 122 g of the product from ex. a 5 is mixed with 2.4 g of acrylic acid, 24 mg of hydroquinone monomethyl ether, 2.5 g of para-toluene sulfonic acid and 55 g of xylene under a nitrogen atmosphere. When heated to 150°C, 0.6 ml of water is removed within 3 hours. To regulate the complete esterification, the acid number (i.e. the amount of still free acrylic acid) in the solution is used. This must be reduced from the theoretical starting value of 20 to at least 6 in order to demonstrate sufficient esterification. The acrylic acid ester is obtained as a 70% clear solution in xylene. This is e.g. A3 in the following table.

2) 609.4 g of the product from ex. A15 is mixed with 7.9 g of acrylic acid, 79 mg of hydroquinone monomethyl ether, 7.6 g of para-toluenesulfonic acid and 268 g of xylene under a nitrogen atmosphere. When heated to 150 °C, 1.9 ml of water is removed within 3 hours. The acid value drops after 3 hours to a value of

4.0. After esterification with acrylic acid has been completed, it is cooled, 14.3 g of acetic anhydride are added and heated to 100°C for 2 hours. This is e.g. A14 in the following table.

The procedures in the further examples are similar. Optionally, longer or shorter reaction times are used to achieve complete esterification and end-group closure.

B) Copolymerization of the hydrophobic unsaturated

ester from A) with comonomers

Example

To 587 g of the solution of the esterified alcohol prepared under A3, 72 g of acrylic acid, 284 mg of 2,2'-azo-bisisobutyronitrile and 307 g of xylene are added under a nitrogen atmosphere, and the mixture is stirred for 3 hours at 80°C. It is then heated for 2 hours at 110° C. The obtained copolymer has an A value of 28.3 (measured as 1% xylene solution). This is example B1 in the following table.

Example 2

764 g of the solution of the esterified alcohol prepared under Al are added to 212 mg of 2,2'-azo-bisisobutyronitrile and stirred under a nitrogen atmosphere for 2 hours at 90°C. 72 g of acrylic acid and 72 g of xylene are then added and stirred for a further 15 hours at 100°C. This is example B2 in the following table.

Example 3

To 707 g of the solution of the esterified alcohol prepared under A5, 10 g of acrylic acid, 156 mg of 2,2'-azo-bisisobutyronitrile and 293 g of xylene are added under a nitrogen atmosphere, and the solution is heated to 80°C. A solution of 62 g of acrylic acid in 62 g of xylene is then added drop by drop over the course of 10 hours. After the addition has been completed, the mixture is stirred for a further 5 hours at 120°C. This is example B3 in the following table.

Example 4

To 893 g of the solution of the esterified alcohol prepared under A15, 95.8 g of acrylic acid, 0.94 g of n-butyraldehyde and 350 g of xylene are added under a nitrogen atmosphere and the solution is heated with stirring to 90°C. Over the course of 3 hours, a solution of 486 mg of 2,2'-azo-bisisobutyronitrile in 103 g of xylene is added dropwise. After the addition has been completed, it is left to react for a further 2 hours. This is example B16 in the following table.

Example 5

95.8 g of acrylic acid, 436 mg of 2,2'-azo-bisisobutyronitrile and 453 g of xylene are added under a nitrogen atmosphere to 893 g of the solution of the esterified and partially end-group-closed alcohol prepared under A14. It is heated for 3 hours at 80°C and then azeotropic water is removed for 3 hours under reflux. The product is available as a 50% solution in xylene, has a K value of 21.2 (measured as a 1% xylene solution) and has an OH number of less than 1. This is example B17 in the following table.

The subsequent products are synthesized analogously to the example above. In the copolymerization, where two different esters from A are used), both components are used at the beginning of the polymerization, and proceed analogously to examples 1 to 3. In the copolymerization with two different comonomers, both are added before the beginning of the reaction (analogous to ex . 1) or drips the comonomer mixture slowly during the reaction (analogous to ex. 3).

C) End-group closure and neutralization of the catalytic amounts of acid after termination

polymerization

In the following example, in which 70% of the OH groups present are closed with acetic anhydride, a supplementary further esterification of the rest of the OH groups is carried out by azeotropic esterification and a neutralization of the p-toluenesulfonic acid with tributylamine, and this should only give examples on the possibilities that end-group closure and neutralization provide. The higher the number of free OH groups after the end group closure, the stronger the K value of the polymer rises in the subsequent azeotropic esterification.

Example 1

95.8 g of acrylic acid, 453 mg of 2,2'-azo-bisisobutyronitrile and 460 g of xylene are added under a nitrogen atmosphere to 893 g of the solution of the esterified alcohol produced under Al5 and polymerized for 3 hours at 80°C. The K value of the obtained copolymer is 13.2 (measured as a 1% xylene solution). The solution is allowed to cool, 14.3 g of acetic anhydride is added and heated for 3 hours at 100°C. The mixture is then heated for 3 hours at from 140 to 145°C and azeotropic water is removed. After cooling to 40°C, 7.7 g of tributylamine and after stirring for 2 hours. The product is available as a medium viscous 50% solution in xylene. The K value is 23.8 (measured as a 1% xylene solution). The OH number is less than 1. This is eg Cl in the following table.

D) Modification of the copolymers produced under B) and C).

The following example should only make it clear by way of example which modifications can be carried out with the polymers from B) and C).

a) Mixing with alkoxylated alcohols and/or co-surfactants 1. 966 g of the solution of the copolymer prepared under B1 are mixed together with 61 g of the alcohol alkylated under al4 and 61 g of xylene. 2. 768 g of the solution of the copolymer prepared under B9 is mixed with 128 g of dodecyl hydrogen sulfate

and 1613 g of methanol.

b) Partial esterification of the mixture prepared under C).

50 g of the solution of the product from B14 is mixed with

6.5 g of the alkoxylated alcohol produced under al3 and 6.5 g of that produced under al4, and in addition another 52 g of xylene added. When boiling under reflux, 0.8 ml of water is removed in the course

of 4 hours.

c) Supplementary cross-linking of the copolymers from B)

50 g of the solution of the product from B10 is added 1 g

bisglycidyl ether of bisphenol A (epicote) and it is heated at 100°C for 8 hours. The viscous solution

is diluted by adding 35 g of xylene.

d) Supplementary alkoxylation of the copolymers produced under B) and C) with ethylene oxide and/or propylene oxide

and or butylene oxide

10 g of the solution of the copolymer prepared under B7 is added to 1 g of potassium hydroxide and reacted with 50 g of propylene oxide in an autoclave at 6 bar and at 130-140°C. After completion of the reaction, another 290 g of ethylene oxide is dosed in portions at 120-130°C. Towards the end of the reaction, the temperature is raised for 2 hours to 150°C.

Claims (8)

1. Reaction mixtures suitable as petroleum emulsion breakers, containing copolymers of acrylic acid or methacrylic acid esters and ethylenically unsaturated comonomers, and other products formed by the reactions, characterized in that the copolymers have been obtained by copolymerization of hydrophobic acrylic or methacrylic acid acid esters, which are obtained by esterification of acrylic acid or methacrylic acid respectively with an alcohol component of polyalkylene glycols and polyalkylene glycol ethers, with hydrophilic ethylenically unsaturated comonomers, and that all or almost all free OH groups in the copolymer at etherification, esterification or urethane formation has been transferred to a no longer reactive form and possibly that the acid used in the esterifications has been neutralized by addition of amine. 2. Reaction mixtures as stated in claim 1, characterized in that the monomeric acrylic acid or Methacrylic acid esters, which are used as starting material, are produced by esterification, with the help of a drawing agent for removing water, of acrylic acid or methacrylic acid with alkoxylates of the formula where R<1> means the residue of a monohydric or polyhydric alcohol or alkylphenol or the residue of an alkylphenol/formaldehyde or alkylphenol/acetaldehyde condensation product, AO is an ethylene oxide, propylene oxide or 1,2-butylene oxide residue or mixtures of these residues or blocks of these residues, and x means a number from 5 to 120. 3. Reaction mixtures as specified in claim 1, characterized in that the free OH groups in the copolymers have been transferred to ester or urethane groups after the copolymerization. 4. Reaction mixtures as stated in claim 1, characterized in that the acid is neutralized by the addition of tert.-amines. 5. Reaction mixtures as specified in claim 1, characterized in that the copolymers are obtained by copolymerization of A) acrylic acid esters or methacrylic acid esters whose alcohol component consists of hydrophobic alkoxylates with the formula where R<1> means the residue of a monohydric or polyhydric alcohol or alkylphenol or the residue of an alkylphenol/formaldehyde or alkylphenol/acetaldehyde condensation product, AO means an ethylene oxide, propylene oxide or 1,2-butylene oxide residue or mixtures of these residues or blocks of these residues, and x means the numbers 5-120, with B) hydrophilic comonomers of the formula where R<2> means hydrogen or the residues -COOH, -COOC2H4OH, -COOC2 H4 N (C2 Hs ) 2 , -CONH2 , CN, , -OCOCHs, -CH2OH, -NHCHO, -COCHa , -COOC2H3, or R<3> means hydrogen or -COOH and R<*> means hydrogen or -CH3, with the proviso that at least one of the residues R<2> or R<3> is a hydrophilic group, whereby A) to B) is present in the weight ratio 300:1 to 1:50, and C) transfer of the free OH groups by etherification, esterification or urethane formation to a no longer reactive form and possibly neutralization of the acid used in the preparation of the ester A) or by the esterification of C) as a catalyst, with a tert.-amine. 6. Process for producing reaction mixtures as specified in claim 1, characterized in that the copolymers are formed by A) acrylic acid or methacrylic acid is esterified with hydrophobic alkoxylates with the formula where R<1> means the residue of a monohydric or polyhydric alcohol or alkylphenol or the residue of an alkylphenol/formaldehyde or alkylphenol/acetaldehyde condensation product, AO means an ethylene oxide, propylene oxide or 1,2-butylene oxide residue or mixtures of these residues or blocks of these residues, and x means the numbers 5-120, in the presence of an acidic esterification catalyst and using drawing agents, and the obtained ester monomers are copolymerized with B) hydrophilic comonomers of the formula where R<2> means hydrogen or the residues -COOH, -COOC2H4OH, -COOC2 H« N (C2 Hs ) 2 , -CONH2 , CN, -OCOCHa, -CH2 OH, -NHCHO, -COCH3 , -COOC2 Hs , or R 3 means hydrogen or -COOH and R 4 means hydrogen or -CH 3 whereby at least one of the residues R<2> or R3 means a hydrophilic group, in the weight ratio A) to B) of 300:1 to 1:50 in a manner known per se, and that C) the still free OH groups are esterified, etherified or transferred to a urethane grouping, and optionally that the acid as in the preparation according to A) or C) is used as a catalyst, is neutralized with an amine. 7. Method as stated in claim 6, characterized in that a partial etherification, esterification or reaction with an isocyanate of the free OH groups is carried out already before the copolymerization. 8. Use of reaction mixtures as stated in claim 1, for demulsification of water containing crude oil.