DD295168A5 - PROCESS FOR PREPARING WATER-SOLUBLE COPOLYMERS - Google Patents

Abstract

The invention relates to a process for the preparation of water-soluble copolymers of aliphatic, monoethylenically unsaturated dicarboxylic acids and unsaturated monomers, which are prepared by stepwise and simultaneous supply of the monomers and an initiator in a Reaktionsgefaesz initially containing only water at a temperature suitable for the polymerization. The polymerization reaction proceeds in the presence of a metal salt activator. The copolymers have a stable composition and have best properties as scale inhibitors, dispersants and incrustation inhibitors. {Process; manufacture; water-soluble copolymers; unsaturated dicarboxylic acids; polymerization; metal salt activator; scale-removing agent; Dispersant; Inkrustrationsinhibitor}

Description

For this 1 page drawing

Field of application of the invention

This invention relates to a process for preparing water-soluble copolymers which can be used as scale dissolvers, dispersants and incrustation inhibitors and have excellent properties therefor. As copolymerized monomeric units, these copolymers include units of monoethylenically unsaturated dicarboxylic acids, e.g. Maleic acid, and units containing at least one comonomer selected from monoethylenically unsaturated monocarboxylic acids, e.g. Acrylic acid, and monoethylenically unsaturated carboxyl-free monomers, e.g. As alkyl esters and acrylic acids were selected.

-3- 295168 characteristic of the known state of the art

Copolymers of monoethylenically unsaturated dicarboxylic acids, monoethylenically unsaturated monocarboxylic acids and monoethylenically unsaturated carboxyl-free monomers can be used as scale dissolvers, dispersants, scale inhibitors in detergents, peptizers and fluxes for drilling fluids. Various processes for the preparation of these copolymers using aqueous solvent systems, including both continuous and batch processes, have been described in the past. As far as is known in the art of copolymers occurring in the present invention, the major differences in the reactivity of dicarboxylic monomers, e.g. Maleic acid, and monocarbon monomers, e.g. Acrylic acid, known. In order to achieve complete or nearly complete polymerization of maleic acid, batch processes in which the faster polymerizing acrylic acid monomer is slowly added to a maleic acid salt "batch" have been used to prepare these copolymers (USP 4,659,793) a recent, continuous process relies on a long residence time in a complex series of reactor, cascade "(U.S. Patent No. 4,725,655). The shortcoming of the copolymeric solutions previously made by the batch "off" process was a high level of unreacted dicarboxylic acids which reduced the effectiveness of the copolymer in certain applications. This problem has apparently been solved by US Pat. No. 4,659,793 which discloses a batch process in aqueous solution for preparing copolymers of monoethylenically unsaturated aliphatic dicarboxylic acids such as maleic acid, itaconic acid, mesaconic acid, fumaric acid, methylenemalonic acid, citraconic acid and their monoalkali metal or monoammonium salts α-β-ethylenically unsaturated monomers having carboxy groups such as methacrylic acid or sulfone groups such as 2-acrylamido-2-methylpropanesulfonic acid. When using (i) a water soluble, free radical reaction initiator, e.g. Hydrogen peroxide, in concentrations of 0.5-10% by weight of the total monomer concentration, and (il) from 1 to 250 ppm of metal ions, e.g. For example, ferric ion and ferric ion, and at a pH in the range of 2 to 7, this method was less than 0.5% by weight at stable molecular weight in reducing the unpolymerized residue to dicarboxylic acids the copolymer apparently successful. The concentration of dicarboxylic acids having 4-6 carbon atoms per molecule was between 10 and 70% by weight, and the concentration of ethylenically unsaturated monomers having 3-10 carbon atoms per molecule was between 30 and 90% by weight of the total mass of the monomers.

A typical batch process is described in U.S. Patent 4,659,793 in which a reactor was simultaneously charged with dicarboxylic acid and metal ion salt. The reaction mixture was heated to a temperature between 40 ° C and 15O ⁰ C, and the initiator and the a-b ethylenically unsaturated monomer was then added in aqueous solution over 3-10 hours in the heated reaction mixture. However, since the reaction process already starts when the monoethylenically unsaturated dicarboxylic acid is in the reaction vessel and the monocarboxylic acid is added together with the initiator over a certain period of time, copolymers are synthesized whose composition changes throughout the reaction. Since the dicarboxylic acid is present in a large concentration in the first stages of the reaction, this results in the preparation of a copolymer composed mainly of the dicarboxylic acid. As the concentration of added monomers increases, the monomer content of the reaction solution is variable; As the concentration of added monomers increases, the composition of the initially produced monomer changes. Similarly, when most of the dicarboxylic acid has been polymerized and the added monomer is now present at a higher concentration than the dicarboxylic acid, the copolymer formed in the latter stages of the reaction will consist primarily of the added monocarbon monomer at this time.

Another disadvantage of the "heel" process set forth in US Pat. No. 4,659,793 is that, for the preparation of the more advantageous copolymers with lower! relative molecular mass in the reaction, a higher metal ion level is required. However, this is not desirable from an ecological point of view, since the metal remains in the final product and could ultimately end up in the environment.

Another method of making these polymers is a continuous cascade process set forth in U.S. Patent No. 4,725,655, which is said to be faster and more economical than a batch process. In this patent, the copolymerization of (a) monoethylenically unsaturated dicarboxylic acids having 4-6 carbon atoms per molecule at concentrations of 40-90% by weight of monomers, (b) monoethylenically unsaturated monocarboxylic acids having 3-10 carbon atoms per molecule at concentrations of 40-90 % By weight of monomers and optionally of carboxyl-free monomers at concentrations below 20% by weight of the monomers. This process, which can be operated only continuously, begins with the filling of all reaction vessels - usually three - with an aqueous solution of a copolymer of monoethylenically unsaturated mono- and dicarboxylic acids, which were prepared in the batch process according to DE-PS-3,147,489 are. In this case, starting polymers are used with a composition similar to the one to be produced. Then the reactors are heated to a temperature between 6O ⁰ C and 15O ⁰ C. Now, the dicarboxylic acid and at least 40% by weight of the monocarboxylic acid are added to the first reactor together with 0.5-6.0% by weight of initiator and sufficient neutralizer solution (20-80% by weight of acid weight) for neutralization. Further amounts of monocarboxylic acid and initiator are added to the second reactor or distributed to all connected reactors. When a comonomer of a caiboxyl-free monomer is used, it may be added to the first reactor or to a compound of the first reactor and those of the cascade. The total amount of monomers used ranges from 20 to 70% by weight of the total weight of the aqueous solution. The reaction solution is removed after a residence time of 0.5-8 hours the last reactor.

Similar to the batch processes described above, a polymer of mixed composition is also formed in this continuous process. This is partly due to the fact that the first introduced copolymers were prepared in a discontinuous process, resulting in dom copolymers of mixed composition. Although all monomers may be added simultaneously to the first reactor to give a more homogeneous composition, after the copolymer has passed into the second reactor and only monocarboxylic acid and / or carboxyl-free monomers are added to the reactor, the composition will change. so that the final product consists mainly of the added monomers. The multi-stage reactors

and the technical equipment required for this process and the control problems associated with this process have detrimental effects on the efficiency of the process and the homogeneity of the composition of the copolymers.

Presentation of the essence of the invention

We have found a process - a continuous or discontinuous in aqueous solution - which, with a high degree of conversion, produces copolymers in a homogeneous and relatively uniform composition of unsaturated aliphatic monoethylenically unsaturated dicarboxylic acids, especially maleic acid, from (ii) Monomers with monocarboxylic acid functionality such as acrylic acid and / or unsaturated monomers with monocarboxylic acid functionality such as the alkyleaters of acrylic acid

 The present invention enables a method with which

a) providing a starting amount of water in a reactor;

b) adding stepwise monomers, polymerization initiators and neutralizing agents introduced as separate streams or as mixtures thereof, each stream feeding at a substantially uniform feed rate and passing the streams over a period of at least 25% or z. B. one-third or more of the total inflow time of the streams, are introduced simultaneously, wherein the monomers (A) 3-65% by weight, for. 5-65% by weight of the total weight of the monomers consisting of at least one monoethylenically unsaturated dicarboxylic acid moi: 4-6 carbon atoms per molecule or a salt or anhydride thereof, and (B) to 35-97% by weight, e.g. 35-95% by weight of the total weight of the monomers, consisting of at least one comonomer selected from monoethylenically unsaturated monocarboxylic acids having 3-6 carbon atoms per monomer molecule and unsaturated carboxyl-free monomers;

(c) introducing a metal salt activating agent into the reactor, which metal salt activating agent may be contained in the initial amount of water, while the addition of the monomers may be added, added after the addition of one or more monomers or added in a combined manner;

(d) the reaction proceeds at a temperature of about 80-200 ⁰ C; and

(E) the resulting copolymer from the reactor bereitgoi shares.

In comparison to the copolymers prepared in the prior art and using the same monomers, copolymers of a more homogeneous composition and potentially improved properties are formed in this relatively uncomplicated process. Similarly, the molecular weight of the copolymers can be controlled since both the residual monomers and the metals contained in the final product can be maintained at an environmentally acceptable level.

In an implementation of the process according to the invention in the water-filled reactor and in the presence of a Metallaltsalzaktivierungsmittels gradually and in substantially constant amounts of three additives, preferably linearly and separated from each other, also in dissolved form, supplied in one addition, the monomers in the other of the Polymerization initiator and in the further contain the neutralizing agent. In another variant, two or more of the three additives are mixed before feeding into the reactor, and in a further variant, a separate addition of the monomers, z. B. as solutions.

Copolymers of the (i) monoethylenically unsaturated dicarboxylic acids and (ii) monoethylenically unsaturated monocarboxylic acids and / or monoethylenically unsaturated carboxyl-free monomers having an average molecular weight of about 1,000 to 100,000 may be added by adding these monomers into the reaction vessel in at least initially approximately equal amounts with water-soluble free radical reaction initiators. In the process of the invention, initially only water or an aqueous solution of a metal salt activator is added to the reactor, which is then heated to a higher temperature.

Monomers, initiators and neutralizing agents are then added, each substance in substantially equal amounts added. For example, the addition of these substances to be added may occur simultaneously and linearly or with slightly differing additions and times.

The metal salt activator may be included in the starting charge, added to the reaction vessel along with the monomers, added after the addition of one or more monomers, or appropriately distributed. The monomers, initiators and neutralizing agents can be used as single streams, e.g. In the form of solutions, into the reaction vessel. One variant is to combine two or more of the three streams prior to their introduction into the reactor. Another preferred variant is the addition of the monomers in individual streams. The amount and timing of the addition of the monomers and the initiator can be made variable in view of the different reactivity of the monomers and thus the conversion of the monomers can be maximized. This process can be operated as both a continuous and a batch process, with preference given to a continuous process.

The composition of the monomers added to the reaction flask corresponds to the composition of the final copolymer product. If the copolymers are fed separately, they are added in substantially equal amounts Zugs'uomengen, preferably linear.

When the monomers used are fed separately and have the same reactivity, it is usually desirable to start adding each monomer at the same time and terminating the addition of each monomer at the same time. However, if the monomers have different reactivities, the amount of addition may vary to compensate for differences in reactivity. When monomers of different reactivity are used, the addition of each of the monomers or monomer solutions can be started at the same time, however, it is desirable to introduce slow reacting monomers in a shorter time compared to the feed time of faster reacting monomers. Therefore, the addition of the slower reacting monomers is stopped before the faster reacting monomers are added. Although a dependency on the degree of

It is best to add the slowly reacting monomers in about 25-75% of the feed tents for the faster reacting monomers into the reaction flasks. Accordingly, if the monomers are fed in separate streams, then the feed is at least initially common, this form of addition being at least 25% and preferably at least 75% of the total feed time of the monomers. Preferably, the plurality of monomers or monomer solutions are fed simultaneously and linearly. The co-feed of cofeed is often followed by a final ("chase") polymerization step to reduce the number of non-polymerizing, slower reacting monomers by means well known in the art, such as (a) post-feed (b) increasing the polymerization temperature, (c) adding an initiator (catalyst) subsequently, or linking these or other processes. Among the monomers used in the process of the present invention are monoethylenically unsaturated dicarboxylic acids having 4-6 carbon atoms per molecule, their salts, e.g. their alkali metal salts and ammonium salts, and the anhydrides of cis-dicarboxylic acids. Among the suitable monomers are z. For example, maleic acid, itaconic acid, mesaconic and fumaric acid, citraconic acid and anhydrides of cis-dicarboxylic acid, e.g. For example, maleic anhydride. Of these monomers, maleic anhydride is most suitable. The concentration of the monoethylenically unsaturated dicarboxylic acid ranges from 3-65% by weight, e.g. B. 5-65% by weight of the total monomer concentration.

Among the monomers used in the process according to the invention are also monoethylenically unsaturated monocarboxylic acids having 3-6 carbon atoms per molecule and / or unsaturated carboxyl-free monomers. The concentration of these monomers ranges from 35-97% by weight, e.g. From 35-95% by weight and preferably from 40-90% by weight of the total monomer concentration. Suitable monoethylenically unsaturated monocarboxylic acids include acrylic acid, methacrylic acid, vinylacetic acid, crotonic acid and acryloxypropionic acid. The most suitable monoethylenically unsaturated monocarboxylic acid is acrylic acid. Examples of suitable unsaturated carboxyl-free monomers are the alkyl esters of acrylic or methacrylic acids such as methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate and isobutyl methacrylate; the hydroxyalkyl esters of acrylic or methacrylic acids such as hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyethyl methacrylate and hydroxypropyl methacrylate; acrylamides; methacrylamides; N-tertiary butylacrylamide; N-methyl acrylamide; N, _1- N-dimethylacrylamide; acrylonitrile; methacrylonitrile; allyl alcohol; allylsulfonic; allylphosphonic; vinylphosphonic; dimethylaminoethyl; dimethylaminoethyl; phosphoethyl; N-vinyl pyrollidone; N-vinylformamide; N-vinylimidazole; ethylene glycol; Trimethylolpiopane (omission, see claim 10, d. The concentration of the carboxyl-free monomer may be up to 80% by weight of the total monomer concentration. As a rule, the concentration is up to 35% by weight and depends on the solubility of the particular monomer in the reaction mixture.

Water-soluble initiators which may be used in this process include i.a. Hydrogen peroxide, t-butyl hydroperoxide, sodium peroxodisulfate, potassium peroxodisulfate, ammonium peroxodisulfate, sodium perphosphate, ammonium perphosphate, potassium perphosphate, 2,2-azobis (cyanovaleric acid) or combinations of these substances. It has been found that the advantageous properties of several of these initiators can be exploited by their use in combinations. For example, hydrogen peroxide allows good control of molecular weight, albeit somewhat at the expense of reacting the monomers, while sodium peroxodisulfate provides for high conversion of the monomers into polymers, but somewhat at the expense of molecular weight control. By combining such initiators as hydrogen peroxide and sodium peroxodisulfate, the desired properties can be achieved in terms of molecular weight control and high conversion of monomers into polymers. The most suitable initiator system is a combination of hydrogen peroxide and sodium peroxodisulfate. The total concentration of the initiator is between 0.5 and 20% and preferably between 1 and 10% by weight of the total weight of the monomers.

Metal salt activators which may be used in this polymerization include, but are not limited to: a. the water-soluble salts of cobalt, iron, copper, nickel, manganese, zirconium and zinc or combinations thereof. Examples of the metal salts are copper sulfate pentahydrate, iron sulfate heptahydrate, copper acetate, iron acetate, manganese acetate, cerium (IV) sulfate, calcium acetate, calcium sulfate, calcium nitrate, zinc acetate, zinc chloride, titanium (III) chloride, titanium (IV) chloride, lead (II) acetate, lead (IV) acetate, copper acetate, iron acetate hydroxide, ferrous and ferrous chloride, ferrous and ferrous D-phosphate, copper (I) and copper (II) chloride, copper (I. ) And copper (II) bromide, copper (I) nitrate, ferric sulfate, manganese bromide, manganese chloride, cobalt (II) acetate, cobalt D0 chloride, cobalt-U nitrate, cobalt sulfate, cerium (III) chloride, cerium (III) nitrate, CeriumdlD sulfate, zinc nitrate, zinc phosphate, zinc sulfate, manganese nitrate, manganese sulfate, lead D chloride, lead (II) nitrate and others The most suitable metal salt activators are the copper containing compounds. It has been found that copper is unique in its ability to control molecular weight and degree of branching while maintaining high conversion of monomers into polymers. Further, this is described in U.S. Serial No. 475,580, filed February 6, 1990, which is of the same name as the assignee of the present invention. The suitable concentration of the salts ranges from 1 to 200 ppm, preferably from 1 to 25 ppm, based on the total weight of the monomers.

The metal anti-activator helps control the molecular weight of the polymers. In general, as the concentration of the metal salt activator increases, the molecular weight decreases. Most preferred are low molecular weight copolymers. However, since the metal salt activator remains therein even when the copolymer is used, it is highly desirable to limit the amount of the metal involved in the reaction, and thus the amount that ultimately ends up in the environment, due to the present environmental problems. By optimizing reaction conditions and using a combination of initiators not limited to this purpose alone, the preferred low molecular weight copolymers can be prepared with a high degree of conversion and a low level of metal initiators. Although the metal salt activator may be added to the starting charge of the roughening apparatus, added to the reaction vessel along with the monomers, or fed after the addition of one or more of the monomers, the most suitable time to add the metal salt initiator is after the addition the dicarboxylic acid, and the most suitable feed variant is the one-time administration of the entire metal activator in aqueous solution.

The polymerization is preferably carried out until the formation of 20-80% by weight of solid matter solids and best until the formation of 30-65% by weight of solid matter. The polymerization temperatures are preferably between 80 and 15O ⁰ C, preferably between 90 and 120 "C. We performed j, the method in a discontinuous manner, so can the injection times for the monomers of 1 up to 10 hours, preferably 1 to 4 hour. If the process is carried out as a continuous process, preferably a residence time of at least 30 minutes should be selected If the degree of residual monomers is higher than desired, subsequent addition of initiator or initiator and monomer may take place , For example, by the addition of a corresponding equivalent basic 20-80%, preferably 40-60% solution corresponding to the acid content of the monomer mixture is preferably carried out by the continuous and linear feed of the neutralizing agent during the entire polymerization process the reaction solution is v preferably in the range of 3 to 7, but most preferably between 4 and 6. Among the suitable bases are sodium hydroxide, potassium hydroxide and ammonium hydroxide. If an alternative to the separate supply of the neutralizing agent is to be found, a combination with the dicarboxylic acid is preferable.

An advantage of the process according to the invention is that the relative monomer concentration in the reaction solution is kept constant in itself and thus the copolymer produced has a uniform and stable composition, such as by taking samples at different times of the Reaktionsablaufos from the reaction medium and by the control the composition of the monomers in the Reaktionsgufäß could be demonstrated by means of a powerful liquid chromatography (HPLC). Similarly, samples were taken from reactions carried out according to the "heel" method described above, which showed that in the first reaction phase "a polymer is formed with a high proportion of monomers initially contained in the reactor. In the further course of the reaction, the proportion of added monomers in the composition of the polymer increases until the polymer produced in the last phases of the reaction consists predominantly of the monomers fed. These results can also be seen from the enclosed drawing (Figure 1), in which the time in hours (h) on the X-axis, and the concentration of maleic acid in% on the Y-axis; Line "A" represents the maleate copolymer prepared in the "paragraph" process, and line "B" represents the maleate copolymer prepared in the process of the invention The copolymers prepared according to the invention can be used to improve incrustation inhibition in concentrations of up to 35% by weight. preferably from 0.1-20% by weight,), and most preferably from 0.5-5.0% by weight, in detergent compositions These compositions may include both a synthetic builder and a water-soluble organic detergent compound, e.g., anionic, nonionic Zwitterionic and ampholytic detergent compounds are not a central theme of the present invention, as these are well known to those skilled in the detergent art.

Among the examples of the builder compounds which can be used in the detergent composition of the present invention are the alkali metal salts of carboxymethyloxysuccinic acid and diglycolic acid, sodium and potassium diphosphate, sodium and potassium tripolyphosphate, ether polycarboxylates, citrates, polycarboxylates, polyacrylic acids and the like Substances extracted starch or cellulose. Other substances that may be included in the composition of a laundry detergent are the substances commonly present therein. Typical examples thereof are soil-carrying substances, hydrotropes, corrosion inhibitors, dyes, fragrances, fillers, abrasives, optical brighteners, enzymes, soap boosters, soap dispersants, germicides, anti-tarnish agents, cationic detergents, plasticizers, dechlorinating agents, polishes and the like. The remaining part of the detergent composition is water.

The detergent composition of the present invention may be provided in any physical form common to such compositions, e.g. As powder, granules, flakes, ingots, tablets, fad, liquids, pastes and. Ä. The detergent composition can be prepared and used in the usual way. Another advantage of the polymers of the invention is that they can biodegrade to some extent. A biodegradable detergent additive consisting of synthetic polymers is advantageous because the use of non-biodegradable polymeric additives may negatively affect the environment by virtue of the formation of polyacids.

Ausfdhrungibelsplele

The present invention will be further described below by the examples given, which are for the purpose of illustration only and are not to be construed as narrowing the scope of the invention. All percentages in the examples refer to parts by weight unless otherwise indicated.

example 1

Into a 3 L four-necked flask equipped with a mechanical stirrer, reflux condenser, and feed hoppers was added 350 g of deionized water and 8 g of a solution of ferrous sulfate heptahydrate in deionized water containing 0.15% by weight. This solution was heated to 9O ⁰ C ± 3 ⁰ C. At this time, a monomer solution was added to 230g of deionized water, 325g of 97% acrylic acid and 147.8g of maleic anhydride solution, 75g of deionized water initiator solution, 25g of sodium peroxodisulfate and 16.7g of 30% hydrogen peroxide, and a neutralizing solution of 300g of 50% sodium hydroxide , 50 Equivalents Percent with respect to the monomers, added linearly and separately over 2.5 hours in the flask, while the temperature was kept stable at 9O ⁰ C ± 3 ⁰ C. At the end of the feed, the system was cooled to 70 ^° C. for 30 minutes. At this temperature, the pH of the solution is controlled by the addition of 280 g of a 40% aqueous solution of NaOH to about 7. The resulting polymeric solution with the pH-word 7 has a solids content of 39.5% and at 25 ⁰ C a Brookfield viscosity of 0,46PaS (460cps). By gel permeation chromatography (GPC), the mass average molecular weight (Mw) was 11900 and the

Number average molecular weight (Mn) determined to be 4310. The residual content of maleic acid was 0.5% and of acrylic acid less than 0.01%, based on the theoretical total mass of the solid substances. The biodegradation of the resulting polymer was 3.3% in a biological oxygen demand (BOD) test run for more than 30 days.

Example 2 The procedure of Example 1 was repeated, except that 25g of sodium peroxydisulfate dissolved in 75g of distilled water and so on

the initiator solution was added. The resulting polymeric solution with the pH 7.1 enthieltzu 40% solids undhatte a Brookfield viscosity of 1.7 PaS (1700cps) at 25 ⁰ C. A GPC was used to determine Mw 27,500 and Mn 5340.

The residual content of may acid was 0.7% and of acrylic acid less than 0.02%, based on the theoretical total mass of Solid substances. Example 3 The procedure of Example 1 was repeated, except that the neutralization solution contained 572 g of 50% sodium hydroxide,

95% equivalent to the monomers, and no polymerization after polymerization. The resulting polymers

Solution has a Brookfield viscosity of 0.17 PaS with the pH 7.8 enthieltzu 41% solids and he '.. ^ at 25 ⁰ C (170cps). By a GPC were determined for Mw 5440 and Mn 1930. The residual content of maleic acid was 4.2% and less than acrylic acid

0.02%, measured on the theoretical total mass of the solids.

Example 4 (comparison) The procedure of Example 1 was repeated except that the solution neutralizing the reaction mixture was not added. The

Neutralization solution to be added after the polymerization was added to 560 g of a 40% solution of sodium hydroxide in

Water increased. The resulting polymeric solution with pH 7.7 contained 41.5% solids and had

25 ⁰ C a Brookfield Viskoyität of 0,25PaS (250cps). By GPC were determined for Mw 10100 and Mn 5900. The

Residual content of maleic acid was more than 5% and of acrylic acid 0.3%, measured on the theoretical total mass of Solid substances. example

Into a 3-L four-terminal flask equipped with a mechanical stirrer, reflux condenser, and feed hoppers was added 350 g of deionized water and 8 g of a solution of sulfate sulfate heptane in deionized water containing 0.15% by weight. This solution was heated to PO ⁰ C ± 3 ⁰ C. At this time, a monomer solution of 240 g of deionized water, 275 g of 97% acrylic acid and 147.8 g of maleic anhydride, 50 g of vinyl acetate, an initiator solution of 75 g of deionized water, 25 g of sodium peroxydisulf & t and 16.7 g of 30% hydrogen peroxide and a neutralization solution of 273 g of 50% strength sodium hydroxide, 50 equivalent% relative to the concentration of acrylic acid and of maleic anhydride, added over 2.5 hours linearly and separately into the flask, maintaining the temperature at 90 ⁰ C ± 3 ⁰ C was maintained. After completion of the feed, the system was cooled to 70 ° C for 30 minutes. At 7O ⁰ C, the pH of the solution by the addition of 230 g of a 50% aqueous NaOH solution was adjusted to about 7.

The resulting polymeric solution with pH 7.4 contained 41.7% solids and had at 25 ⁰ C a Brookfield viscosity of 0,89PaS (890cps). By GPC, Mw 15500 and Mn 5460 were determined. The residual content of maleic acid was 0.7%, of acrylic acid 0.01% and of vinyl acetate 0.07%, based on the theoretical total mass of the solids. In a BOD test conducted over 30 days, the polymer produced was biodegraded to 9.6%.

Examples

The procedure of Example 5 was repeated, except that instead of the vinyl acetate 50g 2-hydroxyethyl methacrylate were used. The resulting polymeric solution with the pH 7.2 containing about 41.4% solids and had at 25 ⁰ C a Brookfield viscosity of 0,93PaS (930cps). A GCP was used to determine Mw 18500 and Mn 5580. The residual content of maleic acid was 0.6%, of acrylic acid 0.01% and of hydroxyethyl methacrylate less than 0.01%, based on the theoretical total mass of the solids. In a more than 30-day BOD test, the polymer produced was biodegraded to 7.0%.

Example 7

Into a 3-L four-necked flask equipped with a mechanical stirrer, reflux condenser, and feed hoppers were added 650 g of deionized water and 16 g of a solution of ferrous sulfate heptahydrate in deionized water containing 0.16% by weight. Diose solution was heated to 9O ⁰ C ± 3 ⁰ C. At this time, a monomer solution of 460 g of deionized water, 650 g of 97% acrylic acid and 295.6 g of maleic anhydride, an initiator solution of 150 g of deionized water, 50 g of sodium peroxodisulfate and 33.4 g of 30% hydrogen peroxide, and a neutralizing solution of 600 g of 50%. sodium hydroxide, 50 equivalent% relative to the monomers, if linearly and separately over 2.5 hours to the flask while the temperature was kept stable at 9O ⁰ C ± 3 "C. the temperature was for further 30 minutes at 90 ⁰ C. held, after which time was 29g acrylic acid and 5g sodium peroxydisulfate dissolved in 45 g of deionized water, over 30 minutes fed linearly and separately after completion of the feed, the system for 30 minutes was cooled to 7O ⁰ C. at this temperature, the pH is... the solution by the addition of 560 g of a 40% aqueous solution of NaOH adjusted to about 7.

The resulting polymeric solution with the pH 7 has a solids content of 40.0% and at 25 ⁰ C a Brookfield viscosity of 0,55PaS (550cps). By GPC, Mw was determined to be 17600 and Mn to be 5210. The residual content of maleic acid was 0.2% and of acrylic acid below 0.01%, based on the theoretical total mass of the solids.

example

Into a 1-L four-necked flask equipped with a mechanical stirrer, reflux condenser, and feed hoppers were added 240 grams of deionized water and 16 grams of a solution of copper sulfate (15% mass to solution) in deionized water. This solution was heated to reflux; at this time, a monomer solution of 200 g of 97% acrylic acid and 42 g of maleic anhydride, an initiator solution of 38.3 g of 30% hydrogen peroxide and a neutralizing solution of 145.5 g of 50% sodium hydroxide, 50 equivalent% to the monomers fed linearly and separately over 2 hours while maintaining the Rückflußerhitzung in the flask. For another 30 minutes, the reflux heating was maintained; Thereafter, the pH was controlled by the addition of 120 g of a 50% aqueous sodium hydroxide solution of about 7. The resulting polymeric solution with a pH of 7.3 has a solids content of 41.3% and at 25 "C a Brookfield viscosity of 0.3 PaS βOOcps.) By GPC Mw was 4080 and Mn was 2620. The residual content of maleic acid was 0.4% and of acrylic acid less than 0.1%, based on the theoretical total mass of the solids.

Example 9

Into a 2-L four-terminal flask equipped with a mechanical stirrer, reflux condenser and feed funnels are added 500 g of deionized water and 4 g of a solution of copper sulfate in deionized water containing 0.15% by weight. This solution was heated to reflux; at this time a monomer solution of 400 g of 97% acrylic acid and 100 g of itaconic acid, an initiator solution of 20.8 g of 30% hydrogen peroxide and a neutralizing solution of 412 g of 50% sodium hydroxide, 75 equivalent% with respect to the monomers, linear and separately 3, Given for 0 hours while maintaining the reflux in the flask. After completion of the feed, the system was cooled to 6O ⁰ C for 30 minutes. At 60 ^° C., the pH of the solution was adjusted to about 7 with 81 g of a 50% solution of sodium hydroxide in water; then 100 g of water were added. The resulting polymer solution contained 42.9% solids and had at 25 ⁰ C a viscosity of Brookflied 30,6PaS (30600cps). With a GPC, Mw was found to be 59,700 and Mn was 14,000. The residue of itaconic acid was 0.04% and of acrylic acid 0.64%, measured on the theoretical total mass of the solids.

Example 10

Into a 2-L, 4-port flask equipped with a mechanical stirrer, reflux condenser, and feed hoppers was added 480 g of deionized water and 32 g of a solution of copper sulfate pentahydrate in deionized water containing 0.15% by weight. This solution was heated to reflux; at this time, a monomer solution of 400 g of 97% acrylic acid and 84.4 g of maleic anhydride, an initiator solution of 160.6 g of 30% hydrogen peroxide and a neutralizing solution of 290.8 g of 50% sodium hydroxide in 20 g of deionized water, 75 equivalent% relative to Monomers, linear and separately for 3.0 hours while maintaining the reflux in the flask. After completion of the supply, the system was 30 minutes cooled to 5O ⁰ C. At 5O ⁰ C, the pH of the solution was adjusted to about 7 with 197 g of a 50% solution of sodium hydroxide.

The resulting polymer solution contained 40.9% solids and had at 25 ⁰ C a Brookfield viscosity of 0,25PaS (250cps). With a GPC Mw was determined to be 4080 and Mn to 2620. The residue of maleic acid was 0.48% and of acrylic acid 0.11%, measured on the theoretical total mass of Festestubstanze.i.

Example 11

Into a 2-L four-terminal flask equipped with a mechanical stirrer, reflux condenser, and feed hoppers were added 600 g of deionized water and 32 g of a solution of copper sulfate pentahydrate in deionized water containing 0.15% by weight. This solution was heated to 90 ^° C ± 3 ^° C; At this time, a monomer solution of 400 g of 97% acrylic acid and 100 g of itaconic acid, an initiator solution of 166.3 g of 30% hydrogen peroxide and a neutralizing solution of 412 g of 50% sodium hydroxide in 100 g of deionized water, 75 equivalent% with respect to the monomers, was linear and added separately in the flask for 3.0 hours while maintaining the temperature of 9O ⁰ C ± 3 ⁰ C. After completion of the feed, the system was cooled to 6O ⁰ C for 30 minutes. At 60 ° C, the pH of the solution was adjusted to about 7 with 81.2 g of a 50% solution of sodium hydroxide. The resulting polymer solution contained 37.6% solids and had at 25 ⁰ C a Brookfield viscosity of 0.1 Pas dOOcps). With a GPC, Mw was found to be 2 550 and Mn was 1660. The residue of itaconic acid was less than 0.01% and of acrylic acid 0.06%, measured on the theoretical total mass of the solids. The results of the following embodiments (12-36) are summarized in Tables 1-3. The aim of Embodiments 12-36 was to optimize the present invention to further reduce the amount of metal activator needed to control the molecular weight of the product and to minimize residual monomer.

Examples 12-21

In a; 250 ml of deionized water (DI) and 2.6 ml of a 0.5% solution of copper nitrate (Cu (NO ₃ ) ₂ .3H ₂ O) were added to two 4-neck round bottom flasks. The solution was heated to 92 ° C-96 ° C; then while maintaining the reaction temperature of about 92 ° C-96 ° C, the following substances were uniformly and linearly fed into the flask: a solution of sodium maleate containing 327 g of a 50% sodium hydroxide solution, 181 g of maleic anhydride and 305 g of DI water; 390 g of 97% acrylic acid; and a catalyst solution of 6.1 g sodium peroxydisulfate, 34 g 35% hydrogen peroxide and 50 g DI water. The feeding of all solutions to be added starts at the same time. The feeding time for the different solutions was different and can be seen in Table 1.

Upon completion of the feed dl · temperature for another hour was maintained and "cooled 0-67 ⁰ C. When the beaten cooling a number were from the polymerization capping agents only at 65 (" Chasers ") was added, the first episode of 10 g sodium metabisulfite in about 30g DI water and then 7g acrylic acid. Thereafter, the second series of this "chaser" was added consisting of a solution of 2 g of t-butyl hydroperoxide and 2 g of sodium bisulfite in about 4 g of water and then repeated two more times The charge was then cooled to 55 ° C with vigorous stirring The monomeric residues were measured and reported in Table 1 together with the molecular weights of the copolymers, the monomeric residues being reported as percentages by weight, based on the theoretical total mass of the solids ,

Table 1 maleate AS Catal. Delivery time, min AS Rest% 2.7 / 1.0 mw MaIeIn 2.1 / 0.88 Ex. 240 240 240 1.4 / 0.1 (before / after chaser) 2.2 / 0.98 240 240 240 22000 0.7 / 0.13 2.2 / 0.5 1.26 / 0.05 12 180 180 180 38000 0.18 / 0.11 1.1 / 0.05 13 180 180 180 -28,000 0.16 / 0.10 0.79 / 0.17 14 150 180 IRO 30000 0.18 / null 0.72 / 0.14 15 150 180 180 20000 0.1 / null 0.76 / 0.37 16 120 180 180 22000 0.06 / 0, Oi 0.5 / 0.2 17 120 180 180 25000 0.06 / 0.02 18 90 180 180 24000 0.30 / 0.14 19 60 180 180 16000 0.30 / 0.08 20 » 15000 21 »

The only "chase" step was the addition of 10g sodium disulphite in 30g DI water.

Examples 22-26

Into a 2-L flask with four ports and a round bottom were added 240 ml of deionized water (DI) and 2.6 ml of a 0.5% solution of copper nitrate. The solution was heated to 92 ° C-96 ° C, then while maintaining the reaction temperature of about 92 ° C-96 ° C, the following substances were uniformly and linearly fed to the flask: a solution of sodium maleate, the 327g of a 50% Sodium hydroxide solution, 181 g of maleic anhydride and 305 g DI water, 376 g of 97% acrylic acid, and a catalyst solution of 6.1 g sodium peroxydisulfate or hydrogen peroxide or both and 40 g DI water is shown in Table 2, in which the amounts are given as percentages of the mass of the monomers The feeding of all the substances started at about the same time, the supply of sodium maleate became 120 minutes, that of maleic acid 180 minutes and that of the catalyst After 240 minutes, the temperature was lowered for another s maintained and then cooled to 65 ° C-75 ° C. Upon cooling, a series of polymerization terminators ("chasers") were added, the first of which consisted of 10g of sodium bisulfite in about 30g of DI water followed by 21g of acrylic acid, followed by the second series of "chasers." a solution of 2 g of t-butyl hydroperoxide and 2 g of sodium bisulfite in about 4 g of water and then repeated three more times. The filling was then cooled to 55 ⁰ C; with vigorous stirring and cooling was then added 352g of a 50% sodium hydroxide solution. The monomeric residues are summarized in Table 2 and compared to the variable sizes in the experiment, the monomeric residues being expressed as percentages by weight, based on the theoretical total mass of the solid components.

Table 2

For example H ₂ O ₂

NAPS \% Mw

AS

Residue %

MaIeIn

(before / after, chaser ")

0.25

0.5

19200 15600 16300 22700 29700

0.14 / 0.10 0.24 / 0.001

0.25 / 0.06 2.3 / 0.56

0.13 / 0.04 1.9 / 0.30

0.11 / 0.04 0.98 / 0.09

0.19 / 0.22 2.2 / 1.20

NaPS = sodium peroxydisulfate

Examples 27-38

Into a 2-L flask with four ports and a round bottom, 250 mL of deionized (DI) water was added and heated to 92 ° C-96 ° C. The following substances were uniformly and linearly fed while maintaining the reaction temperature of 92 ° C-96 ° C: a solution of sodium maleate containing 327 g of 50% sodium hydroxide solution, 181 g of maleic anhydride and 305 g of DI water, 376 g of 97% acrylic acid; a catalyst solution of sodium peroxydisulfate, hydrogen peroxide and 60 g DI water. The amount of sodium peroxydisulfate and hydrogen peroxide in the catalyst feed were varied and presented in Table 3, with the amounts represented as percentages by weight of the monomers. The feeding of the substances to be supplied started at the same time. The delivery time for the substances to be supplied

in total, they were made variable and also shown in Table 3. In the course of the reaction, the additional feed of a solution of 0.013 g of copper nitrate in 2.6 g of DI water was carried out as an "extra portion." The feed time for this metal activator solution was varied and is shown in Table 3.

After completion of the feed, the temperature was maintained for an additional hour before being cooled to 65 ° C-75 ° C. After cooling, the "chaser" sequences were added, the first of which consisted of 30 g sodium disulphite in about 90 g DI water; the second consisted in the supply of 21 g of acrylic acid. The next series, involving the addition of 2 g of t-butyl hydroperoxide and 2 g of sodium bisulfite in about 4 g of water, was repeated three times. Then the charge was cooled to ⁰ C 5S. With vigorous stirring and cooling, 352 g of a 50% sodium hydroxide solution were added.

The monomeric residues are recorded in Table 3 and are compared to the experimentally variable sizes, the monomeric residues being reported as percentages by weight of the theoretical total mass of the solids.

Example 39

(Determination of the dispersion of clay)

The polymers of Examples 9, 10 and 11 were tested for their suitability as a clay disperse. Table 4 summarizes the viscosity data for various clay slips containing these polymers. The following is the description of the procedure used to determine this data.

The first step in the production of the clay slurry was to prepare a stock solution of polymer blends. This was done by mixing the polymer with anhydrous sodium carbonate and deionized water to give a solution of 100g. Two mixtures were prepared: the first to 10% polymer and 15% anhydrous sodium carbonate, the second from 15% polymers and 10% anhydrous sodium carbonate. A clay slip was then prepared by placing a portion of the mixture with deionized water (total weight 210g) in a stirred tank. A sufficient amount of the mixture was used so that the polymeric portion in the clay slip corresponded to the starting dose listed in Table 4. The container was then placed on a Hamilton Beach multi-purpose mixer operating at low speed. 490g of dry clay were added. After all the clay was added, a high speed was set and the mixture was stirred for a further 5 minutes. Subsequently, 500 g of the slip from the stirred tank were filled into a 0.5 liter vessel and cooled to room temperature. Thereafter, the slurry was mixed at low speed in Mehrzweckrührgerät for one minute and then the viscosity measured with a Brookfield DV-II viscometer at 20 rev min ^-1 (spindle no. 2) were measured. The measurement was carried out one minute after the viscometer was switched on. After the first measurement, more of the mixture was added to the slurry to increase the concentration of the polymers by 0.0125% by weight (the clay solids). However, sufficient clay was added to keep the proportion of solids in the slurry at 70%. Again, the slurry was mixed on the multipurpose mixer for one minute at low speed and the viscosity measured. This procedure was repeated until two consecutive additions resulted in increased viscosity. The optimal dosage is achieved with the lowest viscosity.

Table 4 Effect of maleate polymers as dispersants for clay Dosage Polymer and Viscosity PaS (cps)

Polymer 0.1625 0.175 0.1875 0.20 0.2125 0.225

Example 40

(Semi-continuous polymerisation)

Into a 2-liter four-necked flask, mechanical stirrer, reflux condenser, feed hoppers, and bottom drain were added 230 grams of deionized water. The water was heated to 96 ⁰ C ± 3 ° C; at this time, a monomeric solution of 1.275 g of deionized water, 1.372 g of 97% acrylic acid, 710 g of maleic anhydride and 9 g of a solution containing 0.5% by weight of copper nitrate trihydrate, an initiator solution of 234 g of deionized water and 210 g of 35% hydrogen peroxide, and a neutralizing solution of 1.284 g of 50% sodium hydroxide and 360 g of deionized water was fed linearly and separately while the temperature at 96 ⁰ C ± 3 ⁰ C was maintained. After 90 minutes, about one-third (va) of each of these solutions had been fed; as the feed continued, an additional feed of 400 grams of deionized water was started at a dosage of 200 grams of deionized water per 90 minutes.

Simultaneously with the commencement of the deionized water feed, the drain valve was opened by scooping and the contents of the reaction flask were drained at a flow rate such that the total mass of the reactor flask was maintained at 2024.7g After a total of 270 minutes, all feeds were stopped; in the flask 2024,7g were discharged at a constant speed during the following 90 minutes, the temperature at 96 ⁰ C ± 3 ° C was maintained.

The product from the first kettle was placed in a second vessel in which the temperature of 96 ⁰ C ± 3 ° C was maintained. For every 350 g of product from the first kettle, 9.7 g of acrylic acid and 12.2 g of 35% hydrogen peroxide were added.

After a residence time of at least 90 minutes, the polymeric solution was placed in a third vessel and held there until the completion of the polymerizate at a temperature of 96 ⁰ C ± 3 ° C. Only trace amounts of monomers remained. Finally, the solution was cooled to 7O ⁰ C in the course of 30 minutes and the pH adjusted by the addition of 280g of a 40% aqueous NaOH solution to about 7.

1.13 0.89 0,7'f 0.392 0} 344 0.246 (1130) (890) (7? J) (392) (344) (246) 0,680 0,320 ' 0 286 0.282 0.296 0,290 (680) (320) (286) (282) (296) (290) 0.845 0,730 0.348 0.328 0.340 (845) (730) (348) (328) (340)

The resulting polymeric solution with the pH 7.9 had a solids content of 40.8% and at 25 ⁰ C a Brookfield viscosity of 1,376PaS (1375cps). For a GPC, Mw was calculated to be 26900 and Mn was 600 (that is, the equivalent). The residual content of maleic acid was less than 0.05% by mass and less than 0.16% by weight of acrylic acid, based on the theoretical total mass of the solids.

Example 41 (for comparison: the "paragraph" method)

Into a 2-L four-necked flask with mechanical stirrer, reflux condenser, and feed hoppers was added 148 g of maleic anhydride, 470 g of deionized water, and 8.3 g of a solution containing 0.15% by weight of ferrous sulfate heptahydrate dissolved in deionized water. Gradually, 242g of 50% sodium hydroxide was added to the flask. The solution was warmed to 9O ⁰ C ± 3 ° C; at which time 325g of 97% acrylic acid and an initiator solution of 65g deionized water was added 5g Natriumparoxydisulfat and 45g 30% hydrogen peroxide over three hours linearly and separately into the flask while the temperature was maintained at 90 ° C ± 3 ⁰ C. After completion of the feed, the system was cooled to 7O ⁰ C and there were added 310g of deionized water for dilution; then the system was cooled to room temperature.

The resulting polymeric solution with the pH 4 had a solids content of 40% and at 25 ⁰ C a Brookfield viscosity of 1.5 PaS (1500cps). With a GPC, Mw was determined to be 25,000 and Mn was 8,800. The residual content of maleic acid was 0.13% by weight and of acrylic acid less than 0.1% by weight, based on the theoretical total mass of the solid substances.

Example 42

(Inkrustationsinhibition)

This example demonstrates the anti-scale properties of a detergent containing copolymers prepared by the process of this invention and compares these detergents with those made by the "heel" methodology heretofore known in the art.

In a typical European household washing machine, 3kg of cotton and cotton / polyester fabrics, including two terry towels, were washed. To the 90 ° C wash water, which had a hardness of 3EOpm Ca / Mg (3/1), was 0.8% by weight of a typical European detergent of anhydrous sodium carbonate / zeolite containing 3% by weight of a copolymer prepared in the process of this invention , added. The towels underwent the indicated number of washes (Table 5), were ashed at 800 ^° C. for 2 hours; Thereafter, the content of inorganic substances (incrustation) was determined.

The results are shown in Table 5.

The compounds of the present invention can be used to advantage as a detergent additive, corkstone solvent, agent, peptizer, dispersant, flux for drilling fluids used in drilling for oil, and especially as scale inhibitors.

Table S Effect of the polymers on reducing the residue

% Tissue-ash polymer IOWashes 25 washing fingers

Example 40 1.1 1.8

( "Absato' method)

Example 39 0.8 1.5

(continuous

Method)

Sokalan CP-5 1.1 1.8

(Trade mark of BASF)

Claims (16)

1. A process for the preparation of water-soluble copolymers, characterized in that a) providing a starting amount of water in a reactor; b) adding stepwise monomers, polymerization initiators and neutralizing agents introduced as separate streams, or mixtures thereof, each stream being fed at a substantially uniform feed rate and the streams in a period of at least 25% or z. B. one-third or more of the total inflow time of the streams, are introduced simultaneously, wherein the monomers (A) 3-65% by weight, for. B. 5-65% by weight of the total weight of the monomers consisting of at least one monoethyleniscii unsaturated dicarboxylic acid having 4-6 carbon atoms per molecule or a salt or anhydride thereof, and (B) to 35-97% by weight, e.g. 35-95% by weight of the total weight of the monomers, consisting of at least one comonomer selected from monoethylenically unsaturated monocarboxylic acids having 3-6 carbon atoms per monomer molecule and unsaturated carboxyl-free monomers; c) introducing a metal salt activating agent into the reactor, which metal salt activating agent may be contained in the initial amount of water, while the addition of the monomers may be added, added after the addition of one or more monomers or added in a combined manner; d) the reaction proceeds at a temperature of about 80-200 ⁰ C; and e) the resulting copolymer is removed from the reactor. 2. The method according to claim 1, characterized in that the monomers are fed as separate Monomerströmo and at least initially simultaneously, the duration of this simultaneous feed is at least 25% of the total time of the monomer feed. 3. The method according to claim 1 and 2, characterized in that the metal salt activator can be selected from the salts of cobalt, iron, copper, nickel, manganese, zirconium and zinc and, measured in terms of the total mass of the monomers, in an amount of 1- 200 ppm is included. 4. The method according to claim 1 to 3, characterized in that the concentration of the dicarboxylic acid is 10-60% by weight, measured on the total mass of the monomers. 5. The method according to claim 1 to 4, characterized in that the dicarboxylic acid can be selected from maleic acid, itaconic acid, mesaconic acid, fumaric acid, citraconic acid, their salts and anhydrides and combinations thereof. - 6. The method according to claim 1 to 5, characterized in that the initiator concentration is 0.5-20% by weight, preferably 1-10% by weight, based on the weight of the monomers, and / or the initiator under hydrogen peroxide, t-butyl hydroperoxide, Sodium peroxodisulfate, potassium peroxodisulfate, ammonium peroxodisulfate, sodium perphosphate, ammonium perphosphate, potassium perphosphate, 2,2-azobis (cyanovaleric acid). 7. The method according to claim 1 to 6, characterized in that a combination of two or more initiators is used. 8. The method according to claim 1 or 7, characterized in that the polymerization is carried out at a content of solids of 20-80% by weight, for example 30-65% by weight. 9. The method according to claim 1 to 8, characterized in that the monocarboxylic monomer is selected from acrylic acid, methacrylic acid, vinylacetic acid, crotonic acid and acryloxypropionic acid. 10. The method according to claim 1 to 9, characterized in that the carboxyl-free monomer, the alkyl esters of acrylic or methacrylic acids, such as methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate and isobutyl methacrylate; the hydroxyalkyl esters of acrylic or methacrylic acids such as hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyethyl methacrylate and hydroxypropyl methacrylate; acrylamides; methacrylamides; N-tertiary butylacrylamide; N-methyl acrylamide; Ν, Ν-dimethylacrylamide; acrylonitrile; methacrylonitrile; allyl alcohol; allylsulfonic; allylphosphonic; VinylphosphonsäurejDimethylaminoethylacrylat; dimethylaminoethyl; phosphoethyl; N-vinyl pyrollidone; N-vinylformamide; N-vinylimidazole; ethylene glycol; trimethylolpropane triacrylate; diallyl phthalate; vinyl acetate; styrene; Vinylsulfonic acid and its salts; and 2-acrylamido-2-methylpropanesulfonic acid and salts thereof can be selected. 11. The method according to claim 1 to 10, characterized in that one or more polymers, the polymerization initiator and the streams of neutralizing agent in the form of solutions. 12. The method according to claim 1 to 11, characterized in that an aqueous solution of a mixture of dicarboxylic acid, monocarboxylic acid and carboxyl-free monomers are added to the reactor. 13. The method according to claim 1 to 12, characterized in that the pH in the polymerization by the addition of 20-80 equivalent percent of a base, as measured by the acid content of the monomers, between 4 and 6 is maintained. 14. The method of claim 1 to 13, characterized in that the monomers have a different reaction rate, and the product in step (d) has a residue of unreacted, slower reacting monomers, the degree of such unreacted, slower reacting monomers after step ( d) can be reduced with one or more of the following additional steps: (a) adding another, faster-reacting monomer; (b) adding a further initiator; and (c) increasing the polymerization temperature. 15. A process for the preparation of water-soluble copolymers, characterized in that a starting amount of water is provided, are fed to the stepwise, with substantially uniform feed rates monomers, polymerization initiators and neutralizing agents as separate streams or mixtures of said monomers, initiators and neutralizing agent or fed simultaneously in which the said monomers contain from 3 to 65% by weight, for example from 5 to 65% by weight, based on the total mass of the monomers, of at least one monoethylenically unsaturated dicarboxylic acid having 4-6 carbon atoms per monomer molecule, their salts and anhydrides of such a dicarboxylic acid, and 35-97% by weight, z. B. to 35-95% by weight, based on the total weight of the monomers, at least one comonomer, which can be selected from monoethylenically unsaturated monocarboxylic acids having 3-6 carbon atoms per monomer molecule and the unsaturated carboxyl-free acids, said reaction in the presence of a Metallaltsalzaktivators takes place at about 80-200 ⁰ C and after completion of the aforementioned polymerization, the said copolymer is removed 16. A detergent composition, characterized in that it contains a water-soluble detergent compound which is selected from anionic, nonionic, zwitterionic, ampholytic detergent compounds or a mixture thereof; containing a builder selected from the alkali metal salts of carboxymethyloxysuccinic acid and diglycolic acid, sodium and potassium diphosphate, sodium and potassium tripolyphosphate, ether polycarboxylates, citrates, starch or cellulose derived from polycarboxylates and polyacrylic acids, and up to 35% by weight, e.g. From 0.1 to 20% by weight, preferably from 0.5 to 5.0%, by weight of a copolymer made in a process according to claims 1-15.