DE102016225151A1 - Hybrid polymers and use as additives in deep wells - Google Patents

Abstract

The invention relates to water-soluble or water-swellable hybrid polymer containing) 5 wt .-% to 95 wt .-% of a water-soluble and / or water-swellable polysaccharide selected from the group consisting of carrageenan, xanthan gum, karaya gum, tragacanth gum, chitosan, guar Gum, locust bean gum, sclerotium gum, gellan gum, agar, fenugreek gum, konjac gum, or a chemically modified form of these polysaccharides, and b) 5% to 95% by weight of a synthetic polymer containing one or more recurring Contains structural units of the formula (1) or R, R, R hydrogen, methyl or ethyl, Y is a chemical bond, O, CH, C (CH) H, C (O) NR, A is a chemical bond, O, arylene, Phenylene, linear or branched C 1 -C 6 alkylene, a linear mono-hydroxyalkylene group having 2 to 6 carbon atoms or a linear or branched di-hydroxyalkylene group having 3 to 6 carbon atoms, andD is S (O), POH, POR or POQ, andQ is a counterion, and which is characterized in that component b) was radically grafted onto component a) in a precipitation polymerization in a polar solvent or a polar solvent mixture.

Description

The present invention relates to water-soluble and / or water-swellable hybrid polymers based on polysaccharides and synthetic polymers based on sulfonic, phosphonic acids or salts thereof, a process for preparing these hybrid polymers and the use of these polymers as an additive in drilling muds deep wells to reduce water loss at the borehole wall.

Deep well drilling to develop oil and gas deposits requires the use of drilling fluids. During the drilling process, so-called drilling fluids are used, the task of which is, among other things, to convey the drill cuttings to the surface and to cool the drill head. During the drilling process, the hole can pass through porous rock layers. This can lead to the discharge of water from the drilling fluid to the porous rock. In order to prevent this, additives such as water loss reducers, so-called "fluid loss additives" are used.

After the borehole has reached a certain depth, so-called casings are introduced into the borehole. For this purpose, the casings must be fixed, d. H. In the cavity between the mountains and the casings a cement slurry is pumped in, which hardens to a solid rock. The water release of the cement slurry to the porous rock during the pumping process should be low, so that form on the borehole wall no thick filter cake, which would increase the pumping pressure due to the annulus narrowing so strong that the porous rock breaks up. In addition, the cement slurry would not set optimally with too high water release and become permeable to gas and oil. On the other hand, the forming cement mantle in the annulus must reach sufficient strength as quickly as possible and no shrinkage may occur during setting which leads to flow channels for gas, oil and water. An optimal adjustment of the properties of the cement slurry is only possible through additives. The most important additives are retarders, accelerators, dispersants and water loss reducers.

In US 5472051 . US 4555269 . US 4555269 . US 5025040 . EP-1045869 . EP-0116671 . EP-0217608 . EP-0157055 . EP-0217608 . EP-1059316 and EP-0157055 describe synthetic polymers based on the monomer acryloyldimethyltaurate and other co-monomers which have become particularly established as effective water loss reducers in drilling muds and as water loss reducers in cement and gypsum sludges.

The synthetic poly (acryloyldimethyltaurate) copolymers can be produced industrially in two different physical forms, as powders and in liquid form. The liquid form is to be understood as meaning polymer solutions, for example polymer emulsions or dispersions in which the polymer is dissolved in a solvent or dispersed by the use of an emulsifier.

The mentioned poly (acryloyldimethyltaurate) copolymers in powder form have been described in the patent applications, US 5373044 . US 2798053 . EP-1045869 . EP-301532 . EP-816403 . EP-1116733 and EP-1069142 described. All these polymers based on acryloyldimethyltaurate are obtained by means of a precipitation polymerization.

Poly (acryloyldimethyltaurate) copolymers are characterized by their high temperature stability and hydrolytic stability, which limits their biodegradability. In particular, the use of these polymers in marine deep well drilling is controversial due to existing legislation, particularly in the North Sea off the coast of Norway or other Scandinavian countries.

In addition to the synthetic polymers, various polysaccharides or chemically modified polysaccharides, as rheology modifiers, as retarders in cement slurries, or water loss reducers are used in aqueous drilling muds and cement sludges. Due to their mostly natural origin, these polysaccharides are characterized by a good biodegradability.

Disadvantages of using polysaccharides or chemically modified are their low stability in most alkaline drilling fluids. In addition, there is the high temperature and pressure load in the boreholes, which leads to a decomposition of the polysaccharides used or their chemically modified form in the borehole. The resulting decomposition products have a retarding effect and reduce the water loss-reducing properties of the aqueous drilling fluid.

Another disadvantage with the use of polysaccharides or chemically modified polysaccharides in aqueous drilling fluids is that they are divalent in the presence of high concentrations Metal ions can form sparingly soluble compounds that can lead to instability of the aqueous drilling fluid.

Another drawback to the use of polysaccharides or chemically modified polysaccharides in aqueous drilling fluids is the time required to homogeneously dissolve the polysaccharides in the aqueous drilling fluids without causing clumping. This is not to be underestimated, as this problem can generate large time delays, which can be very costly.

Hybrid polymers are also known in the literature. In DE-2330956 . DE-1945340 . IN 2001CA00060 . EP-2138560 . DE-19518620 . EP-1881017 . US 5264470 various hybrid cellulose-based polymers are described.

DE-1945340 describes the synthesis of a hybrid polymer consisting of cellulose and acrylic acid in water and their use in aqueous clay-containing drilling fluids.

Zh., Khim. describes in Visn. L'viv. Politekh. Inst. (1969), no. 39, 12-14, 1970, Abstr. No. 8S1363 a hybrid polymer of polyacrylic acid and cellulose for dewatering a clay-containing aqueous drilling fluid.

In EP-1881016 describes low molecular weight hybrid polymers consisting of grafted carboxylic acids and their salts. Such hybrid polymers are particularly suitable for use in cosmetic and pharmaceutical formulations and as additives in Spülmaschinentabs. The grafting of acryloyldimethyltaurate and its copolymers is not described.

By means of a graft polymerization in water, the synthesis of a hybrid polymer in CN 101519585 described on guar gum with ammonium acrylate and methacrylamide. These hybrid polymers are used in deep wells along with a titanium-containing paraffin-oil solution as a self-crosslinking rheology modifier in oily boron washes.

Other hybrid polymers are in CN 101935097 described as flocculants in the treatment of liquid drilling fluids.

US 5132285 describes cationic or cationic / anionic hybrid polymers and their use in papermaking.

The article from "Journal of Applied Polymer Science" (2009), 114 (3), 1426-1434 describes a hybrid polymer of xanthan gum with 2-acrylamido-2-methyl-1-propanesulfonic acid with the aid of a redox initiator system in water. During the synthesis of the hybrid polymers, even at low concentrations, a marked increase in viscosity occurs. The use of such a synthetic method for commercial use is economically and ecologically unsuitable because only very low yields can be achieved with the aid of the method described. The article also describes the formation of a hydrogel by physical crosslinking with divalent metal ions. At depths, these divalent metal ions are very common in drilling muds and formation waters, and uncontrolled gelation through the use of these hybrid polymers could result, inter alia, in a formation damage. The use of these hybrid polymers as water loss reducers as an additive in drilling fluids can be ruled out due to the aforementioned gelling properties.

The article in the Journal of Applied Polymer Science (2008), 107 (5), 2970-2976, describes the synthesis of a superabsorbent in water based on carragenan, 2-acrylamido-2-methyl-1-propanesulfonic acid and methylenebisacrylamide as a crosslinker. The described superabsorbent forms a highly viscous hydrogel even at low concentrations during the synthesis. The use of such a hybrid polymer as an additive in deep well drilling fluids would result in severe gelling of the drilling fluids and render them useless for the intended use. Purpose-based use as a water loss reducer can be excluded on the basis of these properties.

The use of poly (acryloyldimethyltaurate) copolymers in cement sludges or alkaline drilling fluids in deep wells have only limited biodegradability due to their high temperature and hydrolytic stability. This is a major disadvantage when these synthetic polymers are to be used in marine deep wells. Due to legal provisions, for example in the North Sea, off the coast of Norway or other Scandinavian countries, the synthetic polymers used must be at least 50% biodegradable.

Natural polysaccharide polymers or their chemical modification have a good biodegradability, but have a limited temperature stability and limited stability against divalent metal ions. Their properties as water loss reducers in cement slurries for cementation of deep wells and as an additive in deep well drilling fluids to reduce water loss at the well wall are inadequate.

The hybrid polymers known in the literature can only be used to a limited extent as water loss reducers. In addition, the known syntheses are based on aqueous systems. This makes industrial use more difficult since high viscosities are already produced during production even at low hybrid polymer concentrations. The isolation of the hybrid polymer from these aqueous systems is expensive, energy and cost intensive. In addition, the resulting hybrid polymers have high residual water content and it comes to clumping during the drying process.

Object of the present invention was the synthesis of powdered hybrid polymers which can be used advantageously as additives in drilling fluids from deep wells to reduce the loss of water at the borehole. In direct comparison with the water-soluble and / or water-swellable polysaccharides used, these hybrid polymers should have improved water-loss-reducing properties in aqueous drilling muds. The hybrid polymers to be synthesized should dissolve much faster in aqueous solutions than the corresponding polysaccharide. In addition, the synthesis process should make economic sense. As economically reasonable, it is to be understood that the hybrid polymers can be prepared in a precipitation polymerization process and already occur during the synthesis process as a solid dispersion, so that they do not have to be isolated in an energy-intensive separation step, at low concentrations of water.

Surprisingly, it has now been found that such hybrid polymers can be prepared from a water-soluble and / or water-swellable polysaccharide by a graft polymerization in a polar solvent as a precipitation polymer and these are particularly suitable as an additive in drilling fluids from deep wells to reduce water loss at the borehole.

1. a) 5 Gew.-% bis 95 Gew.-% eines wasserlöslichen und/oder wasserquellbaren Polysaccharid-Polymers ausgewählt aus der Gruppe bestehend aus Carrageenan, Xanthan Gum, Karaya Gum, Tragacanth Gum, Chitosan, Guar Gum, Locust Bean Gum, Sclerotium Gum, Gellan Gum, Agar, Fenugreek Gum, Konjac Gum, besonders bevorzugt Xanthan Gum, Carrageenan, Guar Gum, Chitosan, Fenugreek Gum, Konjac Gum, Tragacanth Gum oder eine chemisch modifizierte Form der genannten Polysaccharid-Polymeren,
2. b) 5 Gew.-% bis 95 Gew.-% eines synthetischen Polymers, das einer oder mehrerer wiederkehrender Struktureinheiten der Formel (1) enthält, oder ausschließlich aus diesen besteht
   
   worin

   R¹, R², R³

   Wasserstoff, Methyl oder Ethyl,

   Y

   eine chemische Bindung, O, CH₂, C(CH₃)H, C(O)NR²,

   A

   eine chemische Bindung, O, Arylen, Phenylen, lineares oder verzweigtes C₁-C₁₂-Alkylen, eine lineare Mono-Hydroxyalkylengruppe mit 2 bis 6 Kohlenstoffatomen oder eine lineare oder verzweigte Di-Hydroxyalkylengruppe mit 3 bis 6 Kohlenstoffatomen,

   D

   S(O), POH, POR³ oder PO^-Q⁺, und

   Q⁺

   ein Gegenion bedeuten, und

die dadurch charakterisiert sind, dass das Hybrid-Polymer durch eine radikalische Pfropfung der Komponente b) auf die Komponente a) in einer Fällungspolymerisation in einem Lösemittel hergestellt wird.The present invention relates to water-soluble or water-swellable hybrid polymers comprising:

1. a) 5% to 95% by weight of a water-soluble and / or water-swellable polysaccharide polymer selected from the group consisting of carrageenan, xanthan gum, karaya gum, tragacanth gum, chitosan, guar gum, locust bean gum, sclerotium gum , Gellan gum, agar, fenugreek gum, konjac gum, most preferably xanthan gum, carrageenan, guar gum, chitosan, fenugreek gum, konjac gum, tragacanth gum or a chemically modified form of said polysaccharide polymers,
2. b) 5 wt .-% to 95 wt .-% of a synthetic polymer containing one or more recurring structural units of formula (1), or consists solely of these
   
   wherein

   R ¹ , R ² , R ³

   Hydrogen, methyl or ethyl,

   Y

   a chemical bond, O, CH ₂ , C (CH ₃ ) H, C (O) NR ² ,

   A

   a chemical bond, O, arylene, phenylene, linear or branched C ₁ -C ₁₂ -alkylene, a linear mono-hydroxyalkylene group having 2 to 6 carbon atoms or a linear or branched di-hydroxyalkylene group having 3 to 6 carbon atoms,

   D

   S (O) POH, POR or PO ^{3 -} Q ^+, and

   Q ⁺

   mean a counterion, and

which are characterized in that the hybrid polymer is prepared by a radical grafting of component b) to the component a) in a precipitation polymerization in a solvent.

Another object of the invention is the use of the hybrid polymers as an additive in drilling fluids from deep wells to reduce the loss of water at the borehole.

The grafting of components b) on component a) is to be understood as meaning that the synthetic polymer b has at least one covalent bond with the component a) used. Preferably, this covalent bond is a -CH ₂ -O-CH ₂ bond.

The hybrid polymers according to the invention are referred to hereinafter as "polymer A" or as "polymers A".

The weight-average molecular weights of these polymers A are preferably 300,000 to 6,000,000, preferably 400,000 to 5,000,000, in particular 500,000 to 3,500,000 g / mol. The weight-average molecular weights can be determined by means of gel permeation chromatography (GPC). The procedure for determining weight average molecular weight by GPC is detailed in Chapter 3 of "Macromolecular Chemistry: An Introduction" by Bernd Tieke, Wiley-VCH, 2nd, completely revised and expanded edition (September 9, 2005) ISBN-10: 3527313796 described.

• Säule: PSS Suprema 30,000 Å 10 µm, 300 mm × 8 mm
• Detektor: RID
• Temperatur: 23 °C
• Fluss: 1 ml/min
• Injektion Volumen: 20 µl
• Eluent: 0.07 mol/l Dinatriumhydrogenphosphat in water
• Kalibierungsmethode: konventionelle Poly(styrolsulfonat) Natriumsalz Kalibration Probenvorbereitung: Ca. 10 mg Probe werden in 10 ml 0.07 mol/l wässriger Dinatriumhydrogenphosphatlösung gelöst und für 15 Min homogenisiert.

The determination of the molecular mass and distribution of the hybrid polymers according to the invention with the GPC were carried out, as far as possible, under the following conditions:

• Column: PSS Suprema 30,000 Å 10 μm, 300 mm × 8 mm
• Detector: RID
• Temperature: 23 ° C
• Flow: 1 ml / min
• Injection volume: 20 μl
• Eluent: 0.07 mol / l disodium hydrogen phosphate in water
• Calibration method: conventional poly (styrenesulfonate) sodium salt Calibration Sample preparation: Approx. 10 mg of sample are dissolved in 10 ml of 0.07 mol / l aqueous disodium hydrogen phosphate solution and homogenized for 15 min.

The relative viscosity or the k value serve as an indicator of the molecular weight. To determine the k value, the polymer A is dissolved in a concentration of (0.5% by weight) in distilled water and the flow time at 20 ° C. is determined by means of Ubbelohde viscometers. This value gives the absolute viscosity of the solution (η _c ). The absolute viscosity of the solvent is (η ₀ ). The ratio of both absolute viscosities gives the relative viscosity Z: $$Z=\frac{n_c}{n_0}$$

From the relative viscosity Z and the concentration C, the k-value can be determined by the following equation: $$LGz=\left(\frac{75*k^2}{1+1.5kc}+k\right)*c$$

The k value of the polymers A is preferably from 100 to 300, in particular from 150 to 270 and particularly preferably from 180 to 250.

A water-soluble and / or water-swellable polysaccharide polymer (also referred to as polysaccharides, polysaccharides, polysaccharides, glycans / glycans or polyoses) of component a) are compounds in which a large number, preferably at least ten, monosaccharide units or else Simple sugars called are linked by a glycosidic bond. These are biopolymers from an unknown number of monosaccharide units or with statistical molecular size distribution.

In a preferred embodiment of the invention, component a) may be a chemical modification of said polysaccharides selected from the group carrageenan, xanthan gum, karaya gum, tragacanth gum, chitosan, guar gum, locust bean gum, sclerotium gum, gellan gum, agar, fenugreek Gum, konjac gum, included.

• - Säurebehandelte Polysaccharide durch Reaktion mit Säuren (z. B. mit Salzsäure, Phosphorsäure oder Schwefelsäure)
• - Alkalisch modifizierte Polysaccharide durch Reaktion mit Laugen (z. B. mit Natronlauge oder Kalilauge)
• - Gebleichtes Polysaccharide durch Behandlung mit Peroxyessigsäure, Wasserstoffperoxid, Natriumhypochlorit, Natriumchlorit, Schwefeldioxid, Sulfiten, Kaliumpermanganat oder Ammoniumpersulfat
• - Enzymatisch modifizierte Polysaccharide durch Behandlung mit Enzymen
• - Oxidierte Polysaccharide durch Oxidation (z. B. mit Natriumhypochlorit)
• - Acetylierte Polysaccharide durch Veresterung (z. B. mit Anhydriden)
• - Hydroxypropyl Polysaccharide durch Reaktion mit Propylenoxid
• - Hydroxyethyl Polysaccharide durch Reaktion mit Ethylenoxid

Chemical modifications of said polysaccharides within component a) are understood to mean that the polysaccharide in question has undergone various chemical conversion processes and is in a chemically modified form. In some modified polysaccharides of component a), several conversion processes can also be carried out in succession. Modified polysaccharides by chemical transformation processes are to be understood as:

• Acid-treated polysaccharides by reaction with acids (eg with hydrochloric acid, phosphoric acid or sulfuric acid)
• Alkali-modified polysaccharides by reaction with alkalis (eg with sodium hydroxide solution or potassium hydroxide solution)
• Bleached polysaccharides by treatment with peroxyacetic acid, hydrogen peroxide, sodium hypochlorite, sodium chlorite, sulfur dioxide, sulphites, potassium permanganate or ammonium persulphate
• - Enzymatically modified polysaccharides by treatment with enzymes
• Oxidized polysaccharides by oxidation (eg with sodium hypochlorite)
• Acetylated polysaccharides by esterification (eg with anhydrides)
• - Hydroxypropyl polysaccharides by reaction with propylene oxide
• - Hydroxyethyl polysaccharides by reaction with ethylene oxide

In the polymers A, in each case different structural units of the formula (1) or component a) can be contained. A polymer A may contain, for example, a plurality of structural units derived from polymerizable sulfonic acids or phosphonic acids of formula (1). For example, a polymer A may contain a polysaccharide and a chemical modification of this polysaccharide.

The structural units of the formula (1) of the polymers A are preferably derived from monomers from the group consisting of acryloyldimethyltaurate, acryloyl-1,1-dimethyl-2-methyltaurate, acryloyltaurate, acryloyl-N-methyltaurate, 3-allyloxy-2-hydroxy-1- propanesulphonic acid, vinylsulfonic acid, styrenesulfonic acid, vinylphosphonic acid, 2-acrylamido-2-methylpropanephosphonic acid, preferably acryloyldimethyltaurate, vinylsulfonic acid, vinylphosphonic acid and styrenesulfonic acid.

Preferably, the degree of neutralization of the one or more structural units of the formula (1) within the polymers A is from 1 to 100 mol%, more preferably from 50.0 to 100 mol%, particularly preferably from 75.0 to 100 mol% and most preferably from 90.0 to 100 mol%.

In the structural units of formula (1), the counterion Q ^{+ is} selected from the group consisting of H ⁺ , Alkali ⁺ , alkaline earth ⁺⁺ , ½ Zn ⁺⁺ , or ⅓Al ^+++. , NH ₄ ⁺ , morpholine, organic ammonium ions [HNR ⁵ R ⁶ R ⁷ ] ⁺ , wherein R ⁵ , R ⁶ and R ^{7 are} independently hydrogen, a linear or branched alkyl group having 1 to 22 carbon atoms, a linear or branched, simple or polyunsaturated alkenyl group having 2 to 22 carbon atoms, a C ₆ C ₂₂ alkylamidopropyl group, a linear mono-hydroxyalkyl group having 2 to Or at least one of R ⁵ , R ⁶ and R ^{7 is} not hydrogen, or mixtures of these ions.

In a particularly preferred embodiment, the counterion Q is selected from H ⁺ , NH ₄ ⁺ , morpholine, ethanolamine, Li ⁺ , Na ⁺ , K ⁺ , ½ Ca ⁺⁺ , ½ Mg ⁺⁺ , ½ Zn ⁺⁺ and mixtures of these ions and most preferably it is NH ₄ ⁺ , Na ⁺ , morpholine and ethanolamine

In a preferred embodiment of the invention, the grafted synthetic polymer of component b) contains 30 to 100 mol%, in particular 60 to 100 mol% and very preferably 70 to 100 mol% of one or more independent recurring structural units of the general formula ( 1), preferably derived from acryloyldimethyltaurate, vinylsulphonic acid or the vinylphosphonic acid.

wobei

R¹, R³

Wasserstoff, Methyl, Ethyl, oder C(O)O^- Z⁺

X, Y

eine chemische Bindung, O, CH₂, C(O)O, OC(O), C(O)NR³ oder NR³C(O),

M

eine chemische Bindung, -[C(O)O-CH₂-CH₂]_n-, eine lineare oder verzweigte Alkylengruppe mit 1 bis 6 Kohlenstoffatomen, eine lineare oder verzweigte, einfach oder mehrfach ungesättigte Alkenylengruppe mit 2 bis 6 Kohlenstoffatomen, eine lineare Mono-Hydroxyalkylengruppe mit 2 bis 6 Kohlenstoffatomen oder eine lineare oder verzweigte Di-Hydroxyalkylengruppe mit 3 bis 6 Kohlenstoffatomen,

n

eine ganze Zahl von 1 - 5 bedeuten, und

Z+

für H⁺, NH₄ ⁺, organische Ammoniumionen [HNR⁵R⁶R⁷]⁺, wobei R⁵, R⁶ und R⁷ unabhängig voneinander Wasserstoff, eine lineare oder verzweigte Alkylgruppe mit 1 bis 22 Kohlenstoffatomen, eine lineare oder verzweigte, einfach oder mehrfach ungesättigte Alkenylgruppe mit 2 bis 22 Kohlenstoffatomen, eine C₆-C₂₂-Alkylamidopropylgruppe, eine lineare Mono-Hydroxyalkylgruppe mit 2 bis 10 Kohlenstoffatomen oder eine lineare oder verzweigte Di-Hydroxyalkylgruppe mit 3 bis 10 Kohlenstoffatomen sein können, und wobei mindestens einer der Reste R⁵, R⁶ und R⁷ nicht Wasserstoff ist, Li⁺, Na⁺, K⁺, ½ Ca⁺⁺, ½ Mg⁺⁺, ½ Zn⁺⁺ oder ⅓ Al⁺⁺⁺ oder für Mischungen aus diesen Ionen steht.

In a particularly preferred embodiment, the polymers A according to the invention contain, in addition to the structural units of the formula (1), further structural units which are preferably functionalized acrylic or methacrylic acid esters, acrylic or methacrylic acid amides, polyglycolacrylic or methacrylic acid esters, polyglycolacrylacrylic or methacrylic acid amides, dipropyleneglycolacrylic or methacrylic acid esters , Dipropylene glycol acrylic or methacrylic acid amides, ethoxylated fatty alcohol acrylates or methacrylates, propoxylated fatty alcohol acrylates, linear or cyclic N-vinylamides or N-methvinylamides, or derive from monomers of the general formula (2):

in which

R ¹ , R ³

Hydrogen, methyl, ethyl, or C (O) O ^- Z ⁺

X, Y

a chemical bond, O, CH ₂ , C (O) O, OC (O), C (O) NR ³ or NR ³ C (O),

M

a chemical bond, - [C (O) O-CH ₂ -CH ₂ ] _n -, a linear or branched alkylene group having 1 to 6 carbon atoms, a linear or branched, mono- or polyunsaturated alkenylene group having 2 to 6 carbon atoms, a linear Mono-hydroxyalkylene group having 2 to 6 carbon atoms or a linear or branched di-hydroxyalkylene group having 3 to 6 carbon atoms,

n

an integer from 1 to 5, and

Z +

for H ⁺ , NH ₄ ⁺ , organic ammonium ions [HNR ⁵ R ⁶ R ⁷ ] ⁺ , wherein R ⁵ , R ⁶ and R ^{7 are} independently hydrogen, a linear or branched alkyl group of 1 to 22 carbon atoms, linear or branched, simple or polyunsaturated alkenyl group having 2 to 22 carbon atoms, a C ₆ -C ₂₂ alkylamidopropyl group, a linear mono-hydroxyalkyl group having 2 to 10 carbon atoms or a linear or branched dihydroxyalkyl group having 3 to 10 carbon atoms, and at least one of Radicals R ⁵ , R ⁶ and R ^{7 is} not hydrogen, Li ⁺ , Na ⁺ , K ⁺ , ½ Ca ⁺⁺ , ½ Mg ⁺⁺ , ½ Zn ⁺⁺ or ⅓ Al ⁺⁺⁺ or stands for mixtures of these ions.

In a particularly preferred embodiment, the polymers A according to the invention contain, in addition to the structural units of the formula (1), further monomers selected from the group consisting of N-vinylformamide, N-vinylacetamide, N-methyl-N-vinylformamide, N-methyl-N-vinylacetamide , N-vinyl-2-pyrrolidone (NVP), N-vinylcaprolactam, vinyl acetate, methyl vinyl ether, ethyl vinyl ether, methyl allyl ether, ethyl methallyl ether, styrene, acetoxystyrene, methyl methallyl ether, ethyl allyl ether, tert-butylacrylamide, N, N-diethylacrylamide, N, N-dimethylacrylamide, N, N-dimethylmethacrylamide, N, N-dipropylacrylamide, N-isopropylacrylamide, N-propylacrylamide, acrylamide, methacrylamide, methylacrylate, methymethylacrylate, tert-butylacrylate, tert-butylmethacrylate, n-butylacrylate, n-butylmethacrylate, laurylacrylate, laurylmethacrylate, behenylacrylate, Behenyl methacrylate, cetyl acrylate, cetyl methacrylate, stearyl acrylate, stearyl methacrylate, tridecyl acrylate, tridecyl methacrylate, polyethoxy- (5) -methacrylate, polyethoxy- (5) -acrylate, polyethoxy- (10) -methacrylate, polyethoxy- (10) -acrylate, behenyl-polyethoxy- (7 ) methacrylate, behenyl polyethoxy (7) acrylate, behenyl polyethoxy (8) methacrylate, behenyl polyethoxy (8) acrylate, behenyl polyethoxy (12) methacrylate, behenyl polyethoxy (12) acrylate, behenyl polyethoxy) (16) methacrylate, behenyl polyethoxy (16) acrylate, behenyl polyethoxy (25) methacrylate, behenyl polyethoxy (25) acrylate, lauryl polyethoxy (7) methacrylate, lauryl polyethoxy (7) acrylate, lauryl polyethoxy) (8) methacrylate, lauryl polyethoxy (8) acrylate, lauryl polyethoxy (12) methacrylate, lauryl polyethoxy (12) acrylate, lauryl polyethoxy (16) methacrylate, lauryl polyethoxy (16) acrylate, lauryl polyethoxy (22 ) methacrylate, lauryl polyethoxy (22) acrylate, lauryl polyethoxy (23) methacrylate, lauryl polyethoxy (23) acrylate, cetyl polyethoxy (2) methacrylate, Cety lpolyethoxy (2) acrylate, cetyl polyethoxy (7) methacrylate, cetyl polyethoxy (7) acrylate, cetyl polyethoxy (10) methacrylate, cetyl polyethoxy (10) acrylate, cetyl polyethoxy (12) methacrylate, cetyl polyethoxy). (12) acrylate Cetyl polyethoxy (16) methacrylate, cetyl polyethoxy (16) acrylate Cetyl polyethoxy (20) methacrylate, cetyl polyethoxy (20) acrylate, cetyl polyethoxy (25) methacrylate, cetyl polyethoxy (25 ) acrylate, cetyl polyethoxy (25) methacrylate, cetyl polyethoxy (25) acrylate, stearyl polyethoxy (7) methacrylate, stearyl polyethoxy (7) acrylate, stearyl polyethoxy (8) methacrylate, stearyl polyethoxy (8 ) acrylate, stearyl polyethoxy (12) methacrylate, stearyl polyethoxy (12) acrylate, stearyl polyethoxy (16) methacrylate, stearyl polyethoxy (16) acrylate, stearyl polyethoxy (22) methacrylate, stearyl polyethoxy (22 ) acrylate, stearyl polyethoxy (23) methacrylate, stearyl polyethoxy (23) acrylate, stearyl polyethoxy (25) methacrylate, stearyl polyethoxy (25) acrylate, tridecyl polyethoxy (7) methacrylate, tridecyl polyethoxy ( 7) acrylate, tridecyl polythoxy (10) methacrylate, tridecyl polyethoxy (10) acrylate, tridecyl polyethoxy (12) methacrylate, tridecyl polyethoxy (12) acrylate, tridecyl polyethoxy (16) methacrylate, tridecyl polyethoxy (16) acrylate, tridecyl polyethoxy (22) methacrylate, tridecyl polyethoxy (22) acrylate, tridecyl polyethoxy (23) methacrylate, tridecyl polyethoxy (23) acrylate, tridecyl polyethoxy (25) methacrylate, tridecyl polyethoxy (25) acrylate, methoxy polyethoxy (7) methacrylate, methoxy polyethoxy (7) acrylate, methoxy polyethoxy (12) methacrylate, methoxy polyethoxy (12) acrylate, methoxy polyethoxy (16) methacrylate, methoxy polyethoxy (16) acrylate, methoxy polyethoxy (25) methacrylate, methoxy polyethoxy (25) acrylate, acrylic acid, ammonium acrylate, sodium acrylate, potassium acrylate, lithium acrylate, zinc acrylate, calcium acrylate, magnesium acrylate, zirconium acrylate, methacrylic acid, Ammonium methacrylate, sodium methacrylate, potassium methacrylate, lithium methacrylate, calcium methacrylate, magnesium methacrylate , Zirconium methacrylates, zinc methacrylate, 2-carboxyethyl acrylate, ammonium 2-carboxyethyl acrylate, sodium 2-carboxyethyl acrylate, potassium 2-carboxyethyl acrylate, lithium 2-carboxyethyl acrylate, zinc 2-carboxyethyl acrylate, calcium 2-carboxyethyl acrylate, magnesium 2-carboxyethyl acrylate, zirconium 2-carboxyethyl acrylate , 2-Carboxyethyl acrylate oligomers, ammonium 2-carboxyethyl acrylate oligomers, sodium 2-carboxyethyl acrylate oligomers, potassium 2-carboxyethyl acrylate oligomers, lithium 2-carboxyethyl acrylate oligomers, zinc 2-carboxyethyl acrylate oligomers, calcium 2-carboxyethyl acrylate oligomers, magnesium 2-carboxyethyl acrylate oligomers, zirconium 2-carboxyethyl acrylate oligomers, itaconic acid, sodium itaconate, potassium itaconate, lithium itaconate, calcium itaconate, magnesium itaconate, zirconium itaconate, zinc itaconate, 2-ethylacrylic acid, ammonium 2-ethyl acrylate, sodium 2-ethyl acrylate, Potassium 2-ethyl acrylate, lithium lithium 2-ethyl acrylate, calcium 2-ethyl acrylate, magnesium 2-ethyl acrylate, zircon ium 2-ethylacrylate, zinc 2-ethylacrylate, 2-propylacrylic acid, ammonium 2-propylacrylate, sodium 2-propylacrylate, potassium 2-propylacrylate, lithium 2-propylacrylate, calcium 2-propylacrylate, magnesium 2-propylacrylate, magnesium 2-propylacrylate, zirconium 2-propyl acrylate, zinc 2-propyl acrylate.

It is also possible to use monomers having two or more olefinic double bonds. Such monomers are preferably selected from the group consisting of glycerol propoxylate triacrylate (GPTA), trimethylolpropane triacrylate (TMPTA), pentaerythritol diacrylate monostearate (PEAS), polyethylene glycol diacrylate, hexanediol diacrylate (HDDA), and hexanediol dimethacrylate (HDDMA). Particularly preferred is glycerol propoxylate triacrylate (GPTA) and trimethylolpropane triacrylate (TMPTA), preferably N-vinylformamide, N-vinylacetamide, N-methyl-N-vinylacetamide, N-vinyl-2-pyrrolidone (NVP), N, N-diethylacrylamide, acrylamide, methacrylamide , Methyl acrylate, methymethyl acrylate, tert-butyl acrylate, acrylic acid, methacrylic acid, 2-carboxyethyl acrylate, 2-carboxyethyl acrylate oligomers, itaconic acid glycerol propoxylate triacrylate (GPTA), trimethylolpropane triacrylate (TMPTA), pentaerythritol diacrylate monostearate (PEAS) and polyethylene glycol diacrylate.

In a further particularly preferred embodiment of the invention, the grafted synthetic polymer of component b) contains 95 to 99.99 mol%, preferably 97 to 99.9 mol%, of one or more structural units of the formula (1) and 0.01 to 5 mol -%, preferably 0.01 to 3 mol% of one or more independent recurring structural units, which have emerged from one or more monomers having at least two olefinic double bonds. Preferably, such monomers are glycerol propoxylate triacrylate (GPTA), trimethylolpropane triacrylate (TMPTA), pentaerythritol diacrylate monostearate (PEAS), and polyethylene glycol diacrylate.

In a further particularly preferred embodiment of the invention, the grafted synthetic polymer of component b) contains from 5 to 98 mol%, preferably from 20 to 80 mol% of one or more repeating structural units of the formula (1) and from 2 to 95 mol%, preferably 20 to 80 mol% of one or more independent repeating neutral structural units.

In an extraordinarily preferred embodiment of the invention, the grafted synthetic polymer of component b) contains 37.5 to 75 mol%, in particular 40 to 72.5 mol% of one or more independent recurring structural units of the general formula (1), preferably derived from acryloyldimethyltaurate, vinylsulphonic acid, styrenesulphonic acid or the vinylphosphonic acid, from 25 to 62.5 mol%, in particular from 27.5 to 60 mol%, of one or more independent recurring neutral structural units, preferably acrylamide, N-methyl-N-vinylacetamide, N Vinylformamide, or N-vinyl-2-pyrrolidone.

In a further particularly preferred embodiment of the invention, the grafted synthetic polymer of component b) contains from 5 to 79.99 mol%, preferably from 12.5 to 69.75 mol% of one or more recurring structural units of the formula (1), 20 to 75 mole%, preferably 30 to 72.5 mole% of one or more independent recurring neutral structural units and 0.01 to 20 mole%, preferably from 0.25 to 15 mole% of one or more recurring other anionic Structural units resulting from one or more monomers having at least one carboxylate anion.

In a further extraordinarily preferred embodiment of the invention, the grafted synthetic polymer of component b) contains from 18 to 59.5 mol%, in particular from 22.5 to 54.25 mol%, of one or more independent recurring structural units of the general formula (1 ), preferably derived from acryloyldimethyltaurate, vinylsulphonic acid, styrenesulphonic acid or the vinylphosphonic acid, from 40 to 70 mol%, in particular from 45 to 67.5 mol%, of one or more independent recurring neutral structural units, preferably acrylamide, N-methyl-N-vinylacetamide, N vinylformamide, or N-vinyl-2-pyrrolidone and 0.5 to 12 mol%, in particular 0.75 to 10 mol%, of one or more independent recurring anionic structural units which are selected from one or more monomers having at least one carboxylate Anion emerged and preferably from acrylic acid, carboxyethyl acrylate, methacrylic acid or the alkali or Erd derive salts of the above compounds.

The distribution of the various structural units within component b) in the polymers A can be random, block-like, alternating or gradient-like.

The grafted various structural units within component b) on component a) can be linear, branched or crosslinked.

The polymers A of the invention are prepared by free-radical graft polymerization as precipitation polymerization in a polar solvent or solvent mixture using an initiator system which is particularly suitable for grafting reaction. Here, the water-soluble and / or water-swellable polysaccharide polymers of component a) are mixed with a defined amount of water. The polysaccharide polymers of component a) pretreated in this way are dissolved or dispersed in a polar solvent or solvent mixture with the corresponding monomers from which the structural units of components b are derived, and the grafting reaction is carried out in a manner known per se, for. B. by the addition of a radical-forming compound started. In this case, for example, the monomers of the components b presented can be polymerized "directly". However, they can also be neutralized prior to the polymerization by, for example, acidic groups of monomers used being reacted with bases before polymerization, the counterions Q ⁺ and optionally Z ^{+ of} the structural units of formula (1) and formula (2) being formed. Instead of neutralizing the monomers before the polymerization, however, the polymers A can also be neutralized after the graft polymerization with the bases.

In a further preferred embodiment for the preparation of the polymers A according to the invention, acidic monomers from which the structural units of the components b) are derived, prior to the polymerization or the polymer A after the polymerization in a polar solvent or with ammonia, morpholine, ethanolamine or a Li ⁺ , Na ⁺ , K ⁺ , Zr ⁺ , Ca ⁺⁺ , Mg ⁺⁺ , Zn ⁺⁺ , NH ₄ ⁺ -containing base, preferably with the corresponding hydroxides, bicarbonates, carbonates and particularly preferred neutralized with a Na ⁺ , K ⁺ , NH ₄ ⁺ -containing hydrogencarbonates and carbonates.

Preferred Li ⁺ , Na ⁺ , K ⁺ , Zr ⁺ , Ca ⁺⁺ , Mg ⁺⁺ , Zn ⁺⁺ or NH ₄ ⁺ -containing bases for the neutralization of the structural units of the components b are sodium bicarbonate, sodium carbonate, Sodium hydroxide, potassium bicarbonate, potassium carbonate, potassium hydroxide, lithium hydrogencarbonate, lithium carbonate, lithium hydroxide, calcium bicarbonate, calcium carbonate, calcium hydroxide, ammonium bicarbonate, ammonium carbonate, preferably sodium bicarbonate, sodium carbonate, sodium hydroxide, potassium bicarbonate, potassium carbonate, potassium hydroxide, ammonium bicarbonate, ammonium carbonate, particularly preferred are sodium bicarbonate, sodium carbonate, sodium hydroxide, Ammonium hydrogencarbonate and particularly preferred are sodium hydrogencarbonate, sodium carbonate and ammonium hydrogencarbonate.

In a further preferred embodiment for the preparation of the novel polymers A, the graft polymerization is carried out as a free-radical precipitation polymerization in a polar solvent or solvent mixture. The solvent or solvent mixture has a boiling point of 20 to 110 ° C, preferably from 40 to 95 ° C, particularly preferably from 50 to 90 ° C.

• A2) Wasser und
• B₂) einem oder mehreren weiteren polaren Lösemitteln

In a further preferred embodiment for preparing the polymers A according to the invention, the polar solvent contains a mixture of:

• A2) Water and
• B ₂ ) one or more other polar solvents

In a further preferred embodiment for preparing the polymers A according to the invention, component B ₂ ) consists of a solvent which contains one or more polar organic solvents.

In a further preferred embodiment for the preparation of the polymers A according to the invention, component B ₂ ) consists of a solvent mixture which comprises one or more alcohols and one or more ketones.

In a further preferred embodiment for the preparation of the polymers A according to the invention, the component B ₂ ) contains one or more polar solvents selected from the group consisting of methanol, ethanol, 1-propanol, 2-propanol, 2-methyl-2-propanol, 1 Butanol, 2-butanol, dimethyl ketone, diethyl ketone, tetrahydropyran, tetrahydrofuran, 2-methyltetrahydrofuran, 1,3-dioxane, 1,4-dioxane, preferably, ethanol, 1-propanol, 2-propanol, 2-methylpropan-2-ol, 1 Butanol, 2-butanol, dimethyl ketone, tetrahydrofuran, 2-methyltetrahydrofuran, 1,3-dioxane, more preferably 2-propanol, 2-methylpropan-2-ol, dimethyl ketone, tetrahydrofuran, 2-methyltetrahydrofuran, 1,3-dioxane, in particular preferably 2-methylpropan-2-ol and dimethyl ketone.

In a particular embodiment for the preparation of the polymers A according to the invention, different polar solvents can be present within component B ₂ ). A polar solvent according to the invention of component B ₂ ) may contain, for example, dimethyl ketone or 2-methylpropan-2-ol. Another polar solvent according to the invention of component B ₂ ) may contain, for example, a mixture of 2-methylpropan-2-ol and dimethyl ketone.

In a particular embodiment for the preparation of the polymers A according to the invention it is characterized in that the polar solvent mixture contains 0.5 to 30 wt .-%, preferably 1 to 20 wt .-% water and more preferably 2 to 15 wt .-% water.

In a particular embodiment for the preparation of the polymers A according to the invention it is characterized in that the polar solvent mixture 1 to 99.5 wt .-%, preferably 5 to 95 wt .-% and particularly preferably 10 to 90 wt .-% of 2-methylpropane-2 contains -ol.

In a further particular embodiment for the preparation of the polymers A according to the invention, the polar solvent mixture comprises from 0.5 to 10% by weight of water, from 1 to 98.5% by weight of 2-methylpropan-2-ol and from 1 to 98.5% by weight of dimethyl ketone, preferably 0.5 to 7.5% by weight of water, 5 to 94.5% by weight of 2-methylpropan-2-ol and 5 to 94.5% by weight of dimethyl ketone , Particularly preferably 1 to 5 wt .-% water, 7.5 to 91.5 wt .-% of 2-methylpropan-2-ol and 7.5 to 91.5 wt .-% dimethyl ketone.

In a particularly preferred embodiment for the preparation of the polymers A according to the invention, the water-soluble and / or water-swellable polysaccharide polymer (component a)) is treated with water in preparation for the graft polymerization. The treatment of component a) with water preferably be carried out so that the water used is distributed almost homogeneously in the component a). The graft polymerization is preferably carried out in a mixture of 2-methylpropan-2-ol and water. The total water content of this mixture must not exceed 30% by weight, since otherwise lump formation may occur in the course of the grafting polymerization. Specifically, the choice of the type and amount of the solvent mixture must be such that the salt of the repeating structural unit of the formula 1, in particular the acryloyldimethyltaurate is substantially soluble or dispersible therein. Under largely soluble or dispersible is to be understood that even after stopping the agitator no major agglomerates or bonds form, which can lead to impairment when re-hiring the agitator. By contrast, the polymer A which is formed in the course of the reaction should be largely insoluble in the chosen solvent mixture. It is to be understood here to be largely insoluble that in the course of the graft polymerization a readily stirrable, pulpy hybrid polymer paste is formed in which no lumps or adhesions may form. The filtrate obtainable by suction of the paste may have a solids content of at most 5% by weight. If the polymer A is soluble to a greater extent in the chosen solvent or solvent mixture, clumping may occur during drying of the polymer paste. The graft polymerization reaction itself is carried out in a manner known per se by radical-forming compounds such as azo initiators (eg azo-bis-isobutyronitrile, 2,2'-azobis (4-methoxy-2,4-dimethyl valeronitrile), 2,2'-azobis (2,4-dimethyl valeronitrile ), Dimethyl 2,2'-azobis (2-methylpropionate), 2,2'-azobis (2-methylbutyronitrile), 1,1'-azobis (cyclohexane-1-carbonitrile) or 2,2'-azobis [N- (2-propenyl) -2-methylpropionamide]), peroxides (eg, dilauryl peroxide, tert-butyl hydroperoxide, di-tert-butyl peroxide, triphenylmethyl hydroperoxide, benzoyl peroxide), persulfates (e.g., potassium peroxydisulfate, sodium peroxydisulfate, ammonium peroxodisulfate, potassium peroxy mono-sulfate, sodium peroxymonosulfate, ammonium peroxymonosulfate organic persulfates), redox initiator systems or combinations of said radical-forming compounds in a suitable temperature range of from 10 to 120 ° C, preferably between 20 and 80 ° C and more preferably between 30 and 70 ° C, and over a period of time Room continued from 30 minutes to several hours.

In a particularly preferred embodiment for the preparation of the polymers A according to the invention, the graft polymerization reaction is carried out by redox initiator systems such as ammonium peroxydisulfate and sodium sulfite, potassium peroxodisulfate and sodium sulfite, ammonium peroxydisulfate and acorbic acid, potassium peroxodisulfate and acorbic acid, ammonium peroxydisulfate and N, N, N ', N'-tetramethylenediamine, Potassium peroxydisulfate and N, N, N ', N'-tetramethylenediamine, ammonium peroxymonosulfate and N, N, N', N'-tetramethylenediamine, ammonium peroxymonosulfate and acorbic acid, ammonium peroxymonosulfate and thiourea, ammonium peroxymonosulfate and malonic acid, ammonium peroxymonosulfate and glycolic acid, ammonium peroxymonosulfate and malic acid, 2-hydroxy-2-sulfonatoacetic acid and sodium sulfite, 2-hydroxy-2-sulfonatoacetic acid and ammonium peroxymonosulfate, 2-hydroxy-2-sulfonatoacetic acid and N, N, N ', N'-tetramethylenediamine, 2-hydroxy-2-sulfonatoacetic acid and tert Butyl hydroperoxide, N, N, N ', N'-tetramethylenediamine and tert-butyl hydroperoxide, N, N, N', N'-tetramethylenediamine and hydrogen peroxide are started.

In a particularly preferred embodiment for the preparation of the polymers A according to the invention, the graft polymerization reaction is started by a combination of a redox initiator system and an azo initiator.

The polymers A are obtained as a white, voluminous precipitate in the polar solvent mixture. For isolation, all conventional evaporation, drying insulation processes can be used. In particular, the polar solvent mixture can be separated from the product by pressure filtration or distillation. A slight residue of the polar solvent mixture is questionable neither for safety reasons nor for application reasons.

The polymers A produced by the process according to the invention are advantageously suitable for use as water loss reducers in drilling fluid fluids and cement slurries. These are used in deep wells to reduce water loss at the well wall and as a means of reducing water loss in cement sludges. Such additives are also called fluid loss or fluid loss control additives.

Another object of the present invention is the use of the polymers A in water-based drilling fluids. These drilling fluids may contain, in addition to the polymers A further additives. Such additives are, for example, bentonites, clay stabilizers, lignin / ligninsulfonates, pH stabilizers (eg hydroxides), temperature stabilizers (eg monoethanolamine or sulfonated synthetic polymers) and weighting agents (eg barite, magnetite, calcium carbonate, ilmenite, to set the desired density).

Examples:

Method:

Process Example 1

In a 1 liter liter Quickfit flask with anchor stirrer, reflux condenser with flue gas scrubber, combined thermometer / pH meter and a gas inlet tube, 274 g of anhydrous 2-methylpropan-2-ol are mixed with 6 g of distilled water and homogenized. The reaction vessel is in a heating bath thermostat.

This reaction vessel is covered with nitrogen gas and 40 g Acryloyldimethyltaurat registered in a slight nitrogen countercurrent. Subsequently, by NH ₃ introduction to a pH of 6-7 should be neutralized. The acryloyldimethyltaurate ammonium salt does not completely dissolve in the 2-methylpropan-2-ol / water mixture and is partly present as a solid dispersion.

5.55 g of xanthan gum with a homogeneous water content of 3% by weight, 1.25 g of N-vinylpyrrolidone, 7.5 g of acrylamide, 1.25 g of N-vinylformamide and 1.2 g of N, N are added to this solids dispersion , N ', N'-tetramethylenediamine are added to the reaction mixture. If the pH value of the reaction mixture has dripped into the acidic range after addition of comonomer, it is neutralized again by NH ₃ introduction (pH 4.5 - 8). A constant flow of nitrogen is passed through the solution for at least 1 hour. After this inertization time, the residual oxygen can be checked by an oxygen electrode. If the measured value of residual oxygen in the liquid phase exceeds 5 ppm, it may be necessary to continue inerting until this value is reached. Thereafter, the reaction vessel is heated to 40 to 70 ° C. In a gentle stream of nitrogen over a period of 30 to 120 minutes, a solution of 20 g of 2-methyl-2-propanol, 1.3 g of tert-butyl hydroperoxide (70% in water) and 1.13 g of V601 in the reaction mixture added. After about 5 to 10 minutes, the onset of the polymerization reaction can be seen. After complete dosing of the initiator solution, the internal temperature in the reaction vessel through the heating bath is increased to the boiling point of the 2-methylpropan-2-ol / water mixture. Under gentle reflux, the now viscous mass is stirred for two hours. The reaction product, which is present as a viscous suspension of polymer in the 2-methylpropan-2-ol / water mixture, is separated by filtration and subsequent drying in a vacuum oven.

Process Example 2:

140 g of anhydrous 2-methylpropan-2-ol and 140 g of anhydrous dimethyl ketone are mixed with 6 g of distilled water and homogenized in a 1 liter liter Quickfit flask with anchor stirrer, reflux condenser with scrubber, combined thermometer / pH meter and a gas inlet tube. The reaction vessel is in a heating bath thermostat. This reaction vessel is covered with nitrogen gas and 40 g Acryloyldimethyltaurat registered in a slight nitrogen countercurrent. The acryloyldimethyltaurate is then neutralized with 16.3 g of sodium bicarbonate to a pH of 6-7. The acryloyldimethyltaurate ammonium salt does not completely dissolve in the 2-methylpropan-2-ol / water mixture and is partly present as a solid dispersion.

To this solid dispersion 21.4 g of xanthan gum with a homogeneous water content of 3 wt .-%, 15 g of acrylamide, and 1.2 g of N, N, N ', N'-tetramethylenediamine are added to the reaction mixture. If the pH of the reaction mixture has dripped into the acidic range after the comonomer has been added, it is neutralized again by the addition of sodium bicarbonate (pH 4.5-8). A constant flow of nitrogen is passed through the solution for at least 1 hour. After this inertization time, the residual oxygen can be checked by an oxygen electrode. If the measured value of residual oxygen in the liquid phase exceeds 5 ppm, it may be necessary to continue inerting until this value is reached. Thereafter, the reaction vessel is heated to 40 to 70 ° C. In a gentle stream of nitrogen over a period of 30 to 120 minutes, a solution of 20 g of 2-methyl-2-propanol, 1.3 g of tert-butyl hydroperoxide (70% in water) and 1.13 g of V601 in the reaction mixture added. After about 5 to 10 minutes, the onset of the polymerization reaction can be seen. After complete dosing of the initiator solution, the internal temperature in the reaction vessel through the heating bath is increased to the boiling point of the 2-methylpropan-2-ol / dimethyl ketone / water mixture. Under gentle reflux, the now viscous mass is stirred for two hours. The reaction product, which is present as a viscous suspension of polymer in 2-methylpropan-2-ol / dimethyl ketone / water mixture is separated by filtration and subsequent drying in a vacuum oven.

The polymers according to the invention which were prepared by the processes described are listed in Table 1 below. Table 1: Examples of hybrid polymers according to the invention (polymers A) according to method 1 polymer Polysaccharide used Composition of component b) (synthetic polymer) initiator system Co-monomer 1 Co-monomer 2 Co-monomer 3 Co-monomer 3 Co-initiator redox system - /Gew.-% Surname / Mol% Surname / Mol% Surname / Mol% Surname / Mol% /G Surname /G 1 Xanthan gum 10 ACDMT 59 NVP 3.5 AT THE 32 NVF 5.5 V-601 / 1.15 TBHP / TMEDA 0.9 / 1.2 2 Xanthan gum 25 ACDMT 59 NVP 3.5 AT THE 32 NVF 5.5 V-601 / 1.15 TBHP / TMEDA 0.9 / 1.2 3 Xanthan gum 50 ACDMT 59 NVP 3.5 AT THE 32 NVF 5.5 V-601 / 1.15 TBHP / TMEDA 0.6 / 0.8 4 Xanthan gum 75 ACDMT 59 NVP 3.5 AT THE 32 NVF 5.5 V-601 / 0.4 TBHP / TMEDA 0.4 / 0.5 5 Xanthan gum 22.5 ACDMT 74 NVP 3.0 AT THE 15 NVF 8th DLP / 1.0 TBHP / TMEDA 0.75 / 1 6 Xanthan gum 42.5 ACDMT 74 NVP 3.0 AT THE 15 NVF 8th DLP / 1.1 TBHP / TMEDA 0.75 / 0.5 7 Guar gum 17.5 ACDMT 59 NVP 3.5 AT THE 32 NVF 5.5 V-601 / 1.15 TBHP / FF6 0.75 / 1.55 8th Guar gum 17.5 ACDMT 74 VPS 3 AT THE 15 NVP 8th DLP / 1.1 TBHP / TMEDA 0.75 / 1 9 Guar gum 17.5 ACDMT 43 AT THE 28.5 VIMA 27.5 AS 1 ABIN / 1.5 TBHP / FF6 1.25 / 2.55 10 chitosan 15.0 ACDMT 59 NVP 3.5 AT THE 32 NVF 5.5 V-601 / 1.15 TBHP / FF6 0.75 / 1.55 11 chitosan 27.5 ACDMT 74 VPS 3 AT THE 15 NVP 8th DLP / 1.1 TBHP / TMEDA 0.75 / 1 12 chitosan 20.0 ACDMT 43 AT THE 28.5 VIMA 27.5 AS 1 ABIN / 1.5 TBHP / FF6 1.25 / 2.55 13 carrageenan 12.5 ACDMT 59 NVP 3.5 AT THE 32 NVF 5.5 V-601 / 1.15 TBHP / FF6 0.75 / 1.55 14 carrageenan 16.0 ACDMT 74 VPS 3 AT THE 15 NVP 8th DLP / 1.1 TBHP / TMEDA 0.75 / 1 15 carrageenan 14.5 ACDMT 43 AT THE 28.5 VIMA 27.5 AS 1 ABIN / 1.5 TBHP / FF6 1.25 / 2.55 16 Fenugreek gum 28.5 ACDMT 59 NVP 3.5 AT THE 32 NVF 5.5 V-601 / 1.15 TBHP / FF6 0.75 / 1.55 17 Fenugreek gum 32.5 ACDMT 74 VPS 3 AT THE 15 NVP 8th DLP / 1.1 TBHP / TMEDA 0.75 / 1 18 Fenugreek gum 30.0 ACDMT 43 AT THE 28.5 VIMA 27.5 AS 1 ABIN / 1.5 TBHP / FF6 1.25 / 2.55 19 Konjac gum 21.5 ACDMT 59 NVP 3.5 AT THE 32 NVF 5.5 V-601 / 1.15 TBHP / FF6 0.75 / 1.55 20 Konjac gum 24.0 ACDMT 74 VPS 3 AT THE 15 NVP 8th DLP / 1.1 TBHP / TMEDA 0.75 / 1 21 Konjac gum 23.0 ACDMT 43 AT THE 28.5 VIMA 27.5 AS 1 ABIN / 1.5 TBHP / FF6 1.25 / 2.55 Table 2: Examples of hybrid polymers according to the invention (polymers A) according to method 2 polymer Polysaccharide used Composition of component b) (synthetic polymer) initiator system Co-monomer 1 Co-monomer 2 Co-monomer 3 Co-monomer 3 Co-initiator redox system Surname /Gew.-% Surname / Mol% Surname / Mol% Surname / Mol% Surname / Mol% /G Surname /G 22 Xanthan gum 10 ACDMT 59 AT THE 32 - - - - V-601 / 1.15 TBHP * / TMEDA 0.9 / 1.2 23 Guar gum 17.5 ACDMT 59 AT THE 32 NVP 3.5 NVF 5.5 V-601 / 1.15 TBHP / TMEDA 0.9 / 1.2 24 chitosan 20.0 ACDMT 43 AT THE 28.5 VIMA 27.5 AS 1 ABIN / 1.5 TBHP / TMEDA 0.6 / 0.8 25 carrageenan 16.0 ACDMT 74 VPS 3 AT THE 15 NVP 8th DLP / 1.1 TBHP / TMEDA 0.4 / 0.5 26 Fenugreek gum 28.5 ACDMT 59 NVP 3.5 AT THE 32 NVF 5.5 V-601 / 1.15 TBHP / FF6 0.75 / 1.55 27 Konjac gum 23.0 ACDMT 43 AT THE 28.5 VIMA 27.5 AS 1 ABIN / 1.5 TBHP / FF6 1.25 / 2.55 ACDMT = acryloyldimethyltaurate, VPS, vinylphosphonic acid, NVP = N-vinyl-2-pyrrolidone, Am = acrylamide, NVF = N-vinylformaid, VIMA = N-vinyl-N-methylacetamide, AS = acylic acid, AIBN = azobis (isobutyronitrile), V601 = Dimethyl 2,2'-azobis (2-methylpropionate), TBHP = tert. Butyl hydroperoxide, TMEDA = N, N, N ', N'-tetramethylethylenediamine, FF6 = Bruggolite FF6 ^®, calculated as 100% strength * Substance

Dissolution rate of the polymers A compared to the corresponding polysaccharide.

In the following application test, the dissolution rate of the polymers A was compared in direct comparison to the polysaccharide used. For this purpose, weighed into a beaker equipped with a magnetic stirrer, 495 g of distilled water and positioned on a magnetic stirrer in a known manner. At a stirring speed of 250 rpm, 5 g of polymer A are added slowly to the aqueous solution and the time required for the polymer A to dissolve completely is measured. The procedure is the same with the corresponding polysaccharide. The required times are compared. Dissolves the polymer A much faster in water on this is marked with a "+" in. A comparable time (+/- 3 min) is indicated by an "O" and a significantly longer time to complete dissolution of the polymer A compared to the corresponding polysaccharide is represented by a "-". Table 2: dissolution rate of the polymers A according to the invention in comparison with the corresponding polysaccharide polymer Polysaccharide used rating 1 Xanthan gum ++ 2 Xanthan gum ++ 3 Xanthan gum ++ 4 Xanthan gum ++ 5 Xanthan gum +++ 6 Xanthan gum +++ 7 Guar gum + 8th Guar gum +++ 9 Guar gum ++ 10 chitosan + 11 chitosan ++ 12 chitosan + 13 carrageenan O / + 14 carrageenan + 15 carrageenan O / + 16 Fenugreek gum ++ 17 Fenugreek gum ++ 18 Fenugreek gum ++ 19 Konjac gum + 20 Konjac gum ++ 21 Konjac gum + 22 Xanthan gum + 23 Guar gum ++ 24 chitosan + 25 carrageenan + 26 Fenugreek gum ++ 27 Konjac gum +

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 5472051 [0004]
• US 4555269 [0004]
• US 5025040 [0004]
• EP 1045869 [0004, 0006]
• EP 0116671 [0004]
• EP 0217608 [0004]
• EP 0157055 [0004]
• EP 1059316 [0004]
• US 5373044 [0006]
• US 2798053 [0006]
• EP 301532 [0006]
• EP 816403 [0006]
• EP 1116733 [0006]
• EP 1069142 [0006]
• DE 2330956 [0012]
• DE 1945340 [0012, 0013]
• IN 2001CA00060 [0012]
• EP 2138560 [0012]
• DE 19518620 [0012]
• EP 1881017 [0012]
• US 5264470 [0012]
• EP 1881016 [0015]
• CN 101519585 [0016]
• CN 101935097 [0017]
• US 5132285 [0018]

Cited non-patent literature

• Zh., Khim. describes in Visn. L'viv. Politekh. Inst. (1969), no. 39, 12-14, 1970, Abstr. No. 8S1363 [0014]

Claims (17)

A water-soluble or water-swellable hybrid polymer comprising a) from 5% to 95% by weight of a water-soluble and / or water-swellable polysaccharide selected from the group consisting of carrageenan, xanthan gum, karaya gum, tragacanth gum, chitosan, guar gum, locust Bean Gum, Sclerotium Gum, Gellan Gum, Agar, Fenugreek Gum, Konjac Gum, or a chemically modified form of these polysaccharides, and b) 5% to 95% by weight of a synthetic polymer containing one or more repeating structural units of the Contains or consists of formula (1)

in which R ¹ , R ² , R ^{3 are} hydrogen, methyl or ethyl, Y is a chemical bond, O, CH ₂ , C (CH ₃ ) H, C (O) NR ² , A is a chemical bond, O, arylene, phenylene, linear or branched C ₁ -C ₁₂ alkylene, a linear mono-hydroxyalkylene group having 2 to 6 carbon atoms, or a linear or branched di-hydroxyalkylene group with 3 to 6 carbon atoms, and DS (O) POH, POR ³ or PO ^- Q ⁺ and Q ^{+ represents} a counterion and which is characterized in that component b) was radically grafted onto component a) in a precipitation polymerization in a polar solvent or a polar solvent mixture. Water-soluble or water-swellable hybrid polymer according to Claim 1 in which the structural units of the formula (1) are derived from monomers from the group consisting of acryloyldimethyltaurate, acryloyl-1,1-dimethyl-2-methyltaurate, acryloyltaurate, acryloyl-N-methyltaurate, 3-allyloxy-2-hydroxy-1 propanesulphonic acid, vinylsulfonic acid, styrenesulfonic acid, vinylphosphonic acid, 2-acrylamido-2-methylpropanephosphonic acid, preferably acryloyldimethyltaurate, vinylsulfonic acid, vinylphosphonic acid and styrenesulfonic acid. Water-soluble or water-swellable hybrid polymer according to claims 1 and / or 2, wherein the counterion Q + is selected from H +, NH Zn ₄ +, morpholine, ethanolamine, Li +, Na +, K +, ½ Ca ++, ½ Mg ++ ½ ++, and mixtures thereof Ions, and more preferably NH ₄ +, Na +, morpholine and ethanolamine. Water-soluble or water-swellable hybrid polymer according to one or more of Claims 1 to 3 in which the grafted synthetic polymer of component b) is preferably derived from 20 to 100 mol%, in particular 35 to 90 mol% and most preferably 40 to 80 mol% of one or more independent recurring structural units of the general formula (1) of acryloyldimethyltaurate, vinylsulphonic acid or vinylphosphonic acid. Water-soluble or water-swellable hybrid polymer according to one or more of Claims 1 to 4 in which, in addition to the structural units of the formula (1), further structural units are contained within component b) derived from functionalized acrylic or methacrylic acid esters, acrylic or methacrylic acid amides, polyglycolacrylic or methacrylic acid esters, polyglycolacrylacrylic or methacrylic acid amides, dipropylene glycolacrylic or methacrylic acid esters , Dipropylene glycol acrylic or methacrylic acid amides, ethoxylated fatty alcohol acrylates or methacrylates, propoxylated fatty alcohol acrylates, linear or cyclic N-vinylamides or N-methvinyl amides, or anionic structural units derived from monomers of general formula (2):

wherein R ¹ , R ^{3 is} hydrogen, methyl or ethyl, C (O) O ^- Z ⁺ X, Y is a chemical bond, O, CH ₂ , C (O) O, OC (O), C (O) NR ³ or NR ³ C (O), M is a chemical bond, - [C (O) O-CH ₂ -CH ₂ ] _n -, a linear or branched alkylene group having 1 to 6 carbon atoms, a linear or branched, mono- or polyunsaturated alkenylene group with 2 to 6 carbon atoms, a linear mono-hydroxyalkylene group having 2 to 6 carbon atoms or a linear or branched di-hydroxyalkylene group having 3 to 6 carbon atoms, n is an integer from 1 to 5, and Z + is H ⁺ , NH ₄ ⁺ , organic ammonium ions [HNR ⁵ R ⁶ R ⁷ ] ⁺ , wherein R ⁵ , R ⁶ and R ^{7 are} independently hydrogen, a linear or branched alkyl group having 1 to 22 carbon atoms, a linear or branched, mono- or polyunsaturated alkenyl group having 2 to 22 Carbon atoms, a C ₆ -C ₂₂ -Alkylamidopropylgruppe, a linear mono-hydroxyalkyl group having 2 to 10 carbon atoms or a linear or branched di-hydroxyalkyl group having 3 to 10 carbon atoms, and wherein at least one of R ⁵ , R ⁶ and R ^{7 is} not hydrogen, Li ⁺ , Na ⁺ , K ⁺ , ½ Ca ⁺⁺ , ½ Mg ⁺⁺ , ½ Zn ⁺⁺ or ⅓ Al ⁺⁺⁺ or stands for mixtures of these ions. Water-soluble or water-swellable hybrid polymer according to one or more of Claims 1 to 5 in which in addition to the structural units of the formula (1) further structural units derived from monomers selected from the group consisting of N-vinylformamide (NVF), N-vinylacetamide, N-methyl-N-vinylacetamide (VIMA), N- Vinyl-2-pyrrolidone (NVP), N, N-diethylacrylamide (DMAA), acrylamide (AM), methacrylamide (MAM), methyl acrylate, methymethyl acrylate, tert-butyl acrylate, acrylic acid (AS), methacrylic acid, 2-carboxyethyl acrylate, 2-carboxyethyl acrylate Oligomers, itaconic acid glycerol propoxylate triacrylate (GPTA), trimethylolpropane triacrylate (TMPTA), pentaerythritol diacrylate monostearate (PEAS) and polyethylene glycol diacrylate. Water-soluble or water-swellable hybrid polymer according to one or more of Claims 1 to 6 in which within component b) 30 to 85 mol%, in particular 40 to 80 mol% of one or more independent recurring structural units of the general formula (1), preferably derived from acryloyldimethyltaurate, vinylsulphonic acid, styrenesulfonic acid or vinylphosphonic acid and 15 to 70 mol%, in particular 20 to 60 mol%, of one or more independent recurring structural units preferably derived from acrylamide, N-methyl-N-vinylacetamide, N vinylformamide, N-vinyl-2-pyrrolidone, acrylic acid and methacrylic acid. Water-soluble or water-swellable hybrid polymer according to one or more of Claims 1 to 7 in which, within component b), from 18 to 59.5 mol%, in particular from 22.5 to 54.25 mol%, of one or more independent recurring structural units of the general formula (1), preferably derived from acryloyldimethyltaurate, vinylsulphonic acid, styrenesulphonic acid or the vinylphosphonic acid, 40 to 70 mol%, in particular 45 to 67.5 mol%, of one or more independent recurring neutral structural units, preferably acrylamide, N-methyl-N-vinylacetamide, N vinylformamide, or N-vinyl-2-one pyrrolidone and 0.5 to 12 mol%, in particular 0.75 to 10 mol%, of one or more independent recurring anionic structural units derived from one or more monomers having at least one carboxylate anion and preferably of acrylic acid, carboxyethyl acrylate, Methacrylic acid or the alkali or alkaline earth salts of the compounds mentioned are included. Water-soluble or water-swellable hybrid polymer according to one or more of Claims 1 to 8th in which the distribution of the various structural units within component b) is random, block-like, alternating or gradient-like. Water-soluble or water-swellable hybrid polymer according to one or more of Claims 1 to 9 in which the grafted-on structural units within component b) on component a) are linear, branched or crosslinked. A process for producing a water-soluble or water-swellable hybrid polymer according to one or more of Claims 1 to 10 in which component a) and monomers from which the structural units of components b) are derived are radically polymerized in precipitation in a polar solvent or solvent mixture, and optionally the monomers of components b before the polymerization or the hybrid polymer after polymerization with ammonia, or a NH ₄ ⁺ , Li ⁺ , Na ⁺ , K ⁺ , Ca ⁺⁺ , Mg ⁺⁺ , Zn ⁺⁺ - Al ⁺⁺⁺ or Zr ⁺⁺⁺⁺ containing base preferably with the corresponding hydroxides, bicarbonates and carbonates are neutralized. A process for the preparation of a water-soluble or water-swellable hybrid polymer Claim 11 wherein the graft polymerization is carried out as a radical precipitation polymerization in a polar solvent or solvent mixture, and the solvent or solvent mixture has a boiling point of 20 to 110 ° C, preferably from 40 to 95 ° C, particularly preferably from 50 to 90 ° C. Process for the preparation of a water-soluble or water-swellable hybrid polymer according to claims 11 and / or 12 wherein the grafting polymerization is carried out in a solvent mixture containing one or more polar solvents selected from the group of methanol, ethanol, 1-propanol, 2-propanol, 2-methyl-2-propanol, 1-butanol, 2-butanol, dimethyl ketone, diethyl ketone, tetrahydropyran, tetrahydrofuran, 2-methyltetrahydrofuran, 1,3-dioxane, 1,4-dioxane, preferably, ethanol, 1-propanol, 2-propanol , 2-methylpropan-2-ol, 1-butanol, 2-butanol, dimethyl ketone, tetrahydrofuran, 2-methyltetrahydrofuran, 1,3-dioxane, more preferably 2-propanol, 2-methylpropan-2-ol, dimethyl ketone, tetrahydrofuran, 2 Methyltetrahydrofuran, 1,3-dioxane, particularly preferably 2-methylpropan-2-ol and dimethyl ketone. A process for producing a water-soluble or water-swellable hybrid polymer according to one or more of Claims 11 to 13 wherein the graft polymerization is carried out in a solvent mixture containing 1 to 99.5 wt .-%, preferably 5 to 95 wt .-% and particularly preferably 10 to 90 wt .-% of 2-methylpropan-2-ol. A process for producing a water-soluble or water-swellable hybrid polymer according to one or more of Claims 11 to 14 wherein the graft polymerization is carried out in a solvent mixture containing 0.5 to 30 wt .-%, preferably 1 to 20 wt .-% water and more preferably 2 to 15 wt .-% water. A process for producing a water-soluble or water-swellable hybrid polymer according to one or more of Claims 11 to 15 wherein the polar solvent after the graft polymerization is separated from the product by filtration, preferably pressure filtration, or distillation. Drilling mud containing one or more water-soluble or water-swellable hybrid polymers according to Anspuch 1 to 10.