DE19917919A1 - Polymer hydrogel mixture, useful for the production of absorption materials, comprises a hydrogel forming polymer having acidic groups and a hydrogel forming polymer having amine and/or imine groups. - Google Patents

Abstract

A hydrogel forming polymer mixture (I) contains: (A) a hydrogel forming polymer having acidic groups; and (B) a hydrogel forming polymer having amine and /or imine groups such that the ratio of acid groups in (A) to the sum of amine and/or imine groups in (B) is 1:9-9:1.

Description

The present invention relates to hydrogel-forming polymer mixtures containing

• a) a hydrogel-forming polymer I with acid residues and
• b) a hydrogel-forming polymer II with amino and / or Imino residues,

where the ratio of the acid residues to the sum of amino / - Imino residues is 1: 9 to 9: 1, as well as the use of these mixtures in absorbent hygiene articles.

The development of new hydrogel-forming polymers, so-called Superabsorbent, with better absorbent properties is after still of great interest, especially in the area of disposable hy Good articles such as diapers or incontinence pads have good absorption properties go hand in hand with great comfort. About it In addition, better superabsorbents enable the use of fewer Superabsorbent amounts, which means the production of thinner hygiene articles enables and is therefore of economic importance since it Packaging and transportation costs reduced.

Superabsorbents show in terms of their absorption capacity Deionized water often gives satisfactory results however, read in exchange for body fluids such as urine sen. This effect of the "poisoning" of the super absorber becomes generally due to the salinity of body fluids guided.

To minimize this effect, WO 96/15162, WO 96/15163, WO 96/17681 and WO 98/37149 a superabsorbent Material consisting of an anionic and a cat ionic superabsorbent material, which cationic superabsorbent material has polymer units that are quaternary amine functions and bisallylbisalkylammoniu mions are attributable.

Mixtures of anionic and cationic are also super absorbent materials, the latter being quaternary amine radio possess ions, i.e. cannot be deprotonated, in the  WO 92/20735, WO 96/15180, DE-A-196 40 329 and WO 98/24832 ben. The polydiallyldimethylammonium hydroxide used herein must be made by polymerizing the corresponding chloride be and then by extensive washing with sodium hydroxide solution are converted to the hydroxide form before it after drying with the anionic superabsorbent mate rial can be mixed.

Furthermore, the salinity of body fluids became the cause for the so-called "gel-blocking" effect, a reduced one Further transport of liquid into deeper superabsorbent layers ten, seen so that US 5,599,335, US 5,669,894 and US 5,562,646 a test method relating to this requirement (Sa line Flow Conductivity SFC) and the resulting requirement describe the profile.

EP-A-0210756 teaches an absorbent mixture of one sorbent mixture of a cation and an anion exchange material that is modified in both cases Is cellulose fiber.

The object of the present invention was to develop a new hydrogel to provide molding polymer blend which is the salt concentration of liquids is reduced and good absorbent Has properties.

Accordingly, the above polymer blends have been found.

Hydrogel-forming polymers I are water-insoluble polymers free acid groups. Crosslinked polyacids, ins special polycarboxylic acids, some of which may exist as a salt nen. Polymers I with an acid group density are preferred (mval / g) <4, especially <8, especially <12.

Preferred polymers I are those obtained by crosslinking polymerization or copolymerization of monoethylenic acid groups unsaturated monomers are produced. It is also possible Lich, the monoethylenically unsaturated acid groups To (co) polymerize monomers without crosslinker and subsequently to network.

Monomers bearing such acid groups are, for example, mono-ethylenically unsaturated C ₃ -C ₂₅ -carboxylic acids or anhydrides such as acrylic acid, methacrylic acid, ethacrylic acid, α-chloroacrylic acid, crotonic acid, maleic acid, maleic anhydride, itaconic acid, citraconic acid, mesaconic acid, glutaconic acid, aconitic acid and fumaric acid. Also suitable are monoethylenically unsaturated sulfonic or phosphonic acids, for example vinylsulfonic acid, allylsulfonic acid, sulfoethyl acrylate, sulfoethyl methacrylate, sulfopropyl acrylate, sulfopropyl methacrylate, 2-hydroxy-3-acryloxypropyl sulfonic acid, 2-hydroxy-3-methacryloxypropylsulfonic acid, vinyl phosphonic acid, vinyl phosphonic acid, vinyl phosphonic acid Acrylamido-2-methyl-propanesulfonic acid. The monomers can be used alone or as a mixture with one another.

Monomers used with preference are acrylic acid, methacrylic acid, Vinylsulfonic acid, acrylamidopropanesulfonic acid or mixtures these acids, e.g. B. mixtures of acrylic acid and methacrylic acid, Mixtures of acrylic acid and acrylamidopropanesulfonic acid or Mixtures of acrylic acid and vinyl sulfonic acid.

To optimize properties, it may be useful to use additional monoethylenically unsaturated compounds which do not carry an acid group but are copolymerizable with the monomers bearing acid groups. These include, for example, the amides and nitriles of monoethylenically unsaturated carboxylic acids, e.g. B. acrylamide, methacrylamide and N-vinylformamide, N-Vinylaceta mid, N-Methyl-N-vinylacetamide, acrylonitrile and methacrylonitrile. Other suitable compounds are, for example, vinyl esters of saturated C ₁ -C ₄ -carboxylic acids such as vinyl formate, vinyl acetate or vinyl propionate, alkyl vinyl ethers with at least 2 C atoms in the alkyl group, such as, for. B. ethyl vinyl ether or butyl vinyl ether, esters of monoethylenically unsaturated C ₃ - to C ₆ -carboxylic acids, for. B. esters of monohydric C ₁ - to C ₁₈ alcohols and acrylic acid, methacrylic acid or maleic acid, half esters of maleic acid, e.g. B. maleic acid monomethyl ester, N-vinyl lactams such as N-vinyl pyrrolidone or N-vinyl caprolactam, acrylic acid and methacrylic acid esters of alkoxylated monohydric, saturated alcohols, e.g. B. from Alko fetch with 10 to 25 carbon atoms that have been reacted with 2 to 200 moles of ethylene oxide and / or propylene oxide per mole of alcohol, such as monoacrylic acid esters and monomethacrylic acid esters of polyethylene glycol or polypropylene glycol, the molecular weights (M _N ) of Polyalkylene glycols can be up to 2000, for example. Other suitable monomers are styrene and alkyl-substituted styrenes such as ethylstyrene or tert. Butyl styrene.

These monomers not bearing acid groups can also be used in Mixture with other monomers are used, for. B. Mixtures from vinyl acetate and 2-hydroxyethyl acrylate in any Relationship. These will not be monomers bearing acid groups the reaction mixture in amounts between 0 and 80% by weight, preferably less than 50 wt .-% added.  

Compounds which have at least 2 have ethylenically unsaturated double bonds. examples for Compounds of this type are N, N'-methylene-bisacrylamide, poly ethylene glycol diacrylates and polyethylene glycol dimethacrylates, the each of polyethylene glycols with a molecular weight of 106 to 8500, preferably 400 to 2000, trimethylol propane triacrylate, trimethylolpropane trimethacrylate, ethylene glycol diacrylate, propylene glycol diacrylate, butanediol diacrylate, hexane diol diacrylate, hexanediol dimethacrylate, allyl methacrylate, Diacrylates and dimethacrylates from block copolymers Ethylene oxide and propylene oxide, two or three times with acrylic acid or methacrylic acid esterified polyhydric alcohols, such as Glycerin or pentaerythritol, triallylamine, tetraallylethylene diamine, divinylbenzene, diallyl phthalate, polyethylene glycol divinyl ethers of polyethylene glycols with a molecular weight of 126 to 4000, trimethylol propanediallyl ether, butanediol divinyl ether, Pentaerythritol triallyl ether and / or divinyl ethylene urea. Preferably, water-soluble crosslinking agents are used, e.g. B. N, N'- Methylene bisacrylamide, polyethylene glycol diacrylates and polyethylene lenglycol-dimethacrylate, which is derived from addition products of 2 up to 400 moles of ethylene oxide with 1 mole of a diol or polyol derive vinyl ethers from addition products from 2 to 400 mol Ethylene oxide with 1 mole of a diol or polyol, ethylene glycol diacrylate, ethylene glycol dimethacrylate or triacrylates and tri methacrylates of addition products of 6 to 20 moles of ethylene oxide to 1 mol of glycerol, pentaerythritol triallyl ether and / or divinyl urea.

Compounds which have min least a polymerizable ethylenically unsaturated group and contain at least one further functional group. The funk tional group of these crosslinkers must be able to use the functional groups, essentially the acid groups of the mono to react. Suitable functional groups are for example hydroxyl, amino, epoxy and aziridino groups. Can be used for. B. Hydroxyalkyl esters of the above ten monoethylenically unsaturated carboxylic acids, e.g. B. 2-hydroxy ethyl acrylate, hydroxypropyl acrylate, hydroxybutyl acrylate, hydroxy ethyl methacrylate, hydroxypropyl methacrylate and hydroxybutyl meth acrylate, dialkyldiallylammonium halides such as dimethyldiallylam monium chloride, diethyl diallyl ammonium chloride, allyl piperidinium bromide, N-vinylimidazoles such as e.g. B. N-vinylimidazole, 1-vinyl-2-methylimidazole and N-vinylimidazolines such as N-vinylimida zoline, 1-vinyl-2-methylimidazoline, 1-vinyl-2-ethylimidazoline or 1-vinyl-2-propylimidazoline, which is in the form of the free bases, in quaternized form or used as a salt in the polymerization can be set. Dialkylaminoalkyl are also suitable  acrylates and dialkylaminoalkyl methacrylates, dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl acrylate and diethylaminoethyl methacrylate. The basic esters will preferably used in quaternized form or as a salt. Furthermore, e.g. B. Glycidyl (meth) acrylate can also be used. The crosslinkers in the reaction mixture are, for example, from 0.001 to 20 and preferably from 0.01 and 14 wt .-% present.

As usual, the polymerization is initiated by an initia gate triggered. As initiators to initiate the polymerization can all radicals bil under the polymerization conditions End initiators are used, which are usually in the Production of superabsorbents can be used. Also one Initiation of the polymerization by the action of electrons blasting onto the polymerizable, aqueous mixture is possible. However, the polymerization can also take place in the absence of In itiators of the type mentioned above through the action of high-energy Radiation can be triggered in the presence of photoinitiators. As Polymerization initiators can all be found under the Polymerisa conditions used in radical-decomposing compounds be, e.g. B. peroxides, hydroperoxides, hydrogen peroxide, per sulfates, azo compounds and the so-called redox catalysts. The use of water-soluble initiators is preferred. In in some cases it is advantageous to use mixtures of different poly to use polymerization initiators, e.g. B. Mixtures of water peroxide and sodium or potassium peroxodisulfate. Mixtures made of hydrogen peroxide and sodium peroxodisulfate can be used in any any ratio can be used. Suitable organic per oxides are, for example, acetylacetone peroxide, methyl ethyl ketone peroxide, tert-butyl hydroperoxide, cumene hydroperoxide, tert-amyl perpivalate, tert-butyl perpivalate, tert-butyl perneohexanoate, tert-butyl perisobutyrate, tert-butyl per-2-ethylhexanoate, tert.- Butyl perisononanoate, tert-butyl permaleate, tert-butyl perbenzoate, Di (2-ethylhexyl) peroxidicarbonate, dicyclohexylperoxydicarbonate, Di (4-tert-butylcyclohexyl) peroxydicarbonate, dimyristilperoxi dicarbonate, diacetyl peroxydicarbonate, allyl perester, cumyl peroxy neodecanoate, tert-butylper-3,5,5-tri-methylhexanoate, acetylcy clohexyl sulfonyl peroxide, dilauryl peroxide, dibenzoyl peroxide and tert-amyl perneodecanoate. Particularly suitable polymerisationini tiators are water-soluble azo starters, e.g. B. 2,2'-Azo bis- (2-amidinopropane) dihydrochloride, 2,2'-azobis- (N, N'-di methylene) isobutyramidine dihydrochloride, 2- (carbamoylazo) iso butyronitrile, 2,2'-azobis [2- (2'-imidazolin-2-yl) propane] dihydro chloride and 4,4'-azobis (4-cyanovaleric acid). The mentioned Po polymerization initiators are used in conventional amounts,  e.g. B. in amounts of 0.01 to 5, preferably 0.1 to 2.0 wt .-%, based on the monomers to be polymerized.

Redox catalysts are also suitable as initiators. The redox catalysts contain at least one of the above per-compounds as the oxidizing component and as reducing component, for example, ascorbic acid, glucose, sorbose, ammonium or alkali metal hydrogen sulfite, sulfite, thiosulfate, hyposulfite, pyrosulfite or sulfide, metal salts , such as iron (II) ions or silver ions or sodium hydroxymethylsulfoxy lat. Ascorbic acid or sodium sulfite is preferably used as the reducing component of the redox catalyst. Based on the amount of monomers used in the polymerization, 3 is used, for example. 10 ^-6 to 1 mol% of the reducing component of the redox catalyst system and 0.001 to 5.0 mol% of the oxidizing component of the redox catalyst.

If the polymerisation by exposure to high energy Triggers radiation, is usually used as an initiator called photoinitiators. This can be, for example so-called α-splitter, H-abstracting systems or azides act. Examples of such initiators are benzophenone deri vate such as Michlers ketone, phenanthrene derivatives, fluorene derivatives, Anthraquinone derivatives, thioxanone derivatives, coumarin derivatives, Benzoin ethers and their derivatives, azo compounds such as those above called radical formers, substituted hexaarylbisimidazoles or Acylphosphine oxides. Examples of azides are: 2- (N, N-dimethyla mino) ethyl 4-azidocinnamate, 2- (N, N-dimethylamino) ethyl 4-azido naphthyl ketone, 2- (N, N-dimethylamino) ethyl 4-azidobenzoate, 5-Azido-1-naphthyl-2 '- (N, N-dimethylamino) ethyl sulfone, N- (4-sulfo nylazidophenyl) maleimide, N-acetyl-4-sulfonylazidoaniline, 4-sul fonylazidoaniline, 4-azidoaniline, 4-azidophenacyl bromide, p-azide topzoic acid, 2,6-bis (p-azidobenzylidene) cyclohexanone and 2,6-bis (p-azidobenzylidene) -4-methylcyclohexanone. The photo If they are used, initiators are usually in Amounts of 0.01 to 5 wt .-%, based on the polymerize the monomers applied.

In the subsequent crosslinking, polyacids are formed by the polymerization of the above monoethylenically unsaturated acids and optionally monoethylenic unsaturated comonomers were produced and the one molecule Lar lar greater than 5000, preferably greater than 50,000, with Compounds implemented at least two against acid have groups reactive groups. This implementation can be done at  Room temperature or at elevated temperatures up to 200 ° C respectively.

The suitable functional groups have already been mentioned above, d. H. Hydroxyl, amino, epoxy, isocyanate, ester, amido and Aziridino groups. Examples of such crosslinkers are ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, Polyethylene glycol, glycerin, polyglycerin, propylene glycol, poly propylene glycol, block copolymers of ethylene oxide and propylene oxide, sorbitan fatty acid ester, ethoxylated sorbitan fatty acid ester, trimethylolpropane, pentaerythritol, 1,3-butanediol, 1,4-butanediol, polyvinyl alcohol, sorbitol, polyglycidyl ether such as Ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, Glycerol diglycidyl ether, glycerol polyglycidyl ether, diglycerol po lyglycidyl ether, polyglycerol polyglycidyl ether, sorbitol polyglyci dyl ether, pentaerythritol polyglycidyl ether, propylene glycol diglyci dyl ether and polypropylene glycol diglycidyl ether, polyaziridine ver bonds such as 2,2-bishydroxymethylbutanol-tris [3- (1-aziridinyl) - propionate], 1,6-hexamethylene diethylene urea, diphenylmethane bis-4,4'-N, N'-diethylene urea, halo epoxy compounds such as Epichlorohydrin and α-methylfluorohydrin, polyisocyanates such as 2, 4-tolylene diisocyanate and hexamethylene diisocyanate, alkylene carbonates such as 1,3-dioxolan-2-one and 4-methyl-1,3-dioxolan-2-one, furthermore bisoxazolines and oxazolidones, furthermore polyquaternary ones Amines such as condensation products of dimethylamine with epichlor hydrine, homo- and copolymers of diallyldimethylammonium chloride as well as homopolymers and copolymers of dimethylamino ethyl (meth) acrylate, optionally with, for example, methyl chloride are quaternized.

Other suitable crosslinkers for postcrosslinking are polyvalent ones Metal ions that are able to form ionic crosslinks form. Examples of such crosslinkers are magnesium, calcium, Barium and aluminum ions. These crosslinkers are, for example as hydroxides, carbonates or hydrogen carbonates of the aqueous po added lymerizable solution. Other suitable crosslinkers are multifunctional bases that are also able to to form ionic crosslinks, for example polyamines or their quaternized salts. Examples of polyamines are ethylene diamine, diethylene triamine, triethylene tetramine, tetraethylene pent amine, pentaethylene hexamine and polyethylene imines as well as polyvinyl amines with molecular weights of up to 4000000 each.

The crosslinkers are polyacrylic acid or polyacrylic acid salts in amounts of 0.5 to 25% by weight, preferably from 1 to 15% by weight, based on the amount of polyacids used added.  

The crosslinked polyacids are used in the invention Polymer mixture preferably used unneutralized. Yet it may be advantageous to partially overhaul the acid functions tralize. The degree of neutralization becomes essentially smaller than 50%, preferably less than 30%. As neutralization middle come into question:

Alkali metal bases or ammonia or amines. Preferably Na tron lye or potash lye used. The neutralization can ever but also with the help of sodium carbonate, sodium hydrogen carbonate, Potassium carbonate or potassium hydrogen carbonate or other carbon ten or hydrogen carbonates or ammonia. In addition, prim., Sec. And tert. Amines can be used.

As a technical process for the manufacture of these products can all methods are used, which are usually used in the manufacture position of superabsorbers are used, as z. B. in Chapter 3 in "Modern Superabsorbent Polymer Technology", F. L. Buchholz and A. T. Graham, Wiley-VCH, 1998.

Polymerization in aqueous solution is preferred as so-called called gel polymerization. 10 to 70% by weight aqueous solutions of the monomers and, if appropriate, a suitable one Graft base in the presence of a free radical initiator polymerisation of the Trommsdorff-Norrish effect.

The polymerization reaction can take place in the temperature range between 0 and 150 ° C, preferably between 10 and 100 ° C, both at normal pressure as well as under increased or reduced pressure leads. As usual, the polymerization can also be carried out in a Protective gas atmosphere, preferably under nitrogen become.

By reheating the polymer gels for several hours at temperature range 50 to 130 ° C, preferably 70 to 100 ° C, the quali properties of the polymers can be improved.

Suitable polymers I are also graft (co) polymers of one or more hydrophilic monomers on a suitable graft basis, cross-linked, acid groups-bearing cellulose or Starch ether and ester, cross-linked carboxymethyl cellulose, or in aqueous liquids swellable natural products with acid groups, such as alginates and carrageenans.

Suitable graft bases can be of natural or synthetic origin. Examples are starch, cellulose or cellulose derivatives and other polysaccharides and oligosaccharides, poly vinyl alcohol, polyalkylene oxides, in particular polyethylene oxides and polypropylene oxides, polyamines, polyamides and hydrophilic polyesters. Suitable polyalkylene oxides have, for example, the formula

wherein
R ¹ and R ² independently of one another are hydrogen, alkyl, alkenyl or acrylic,
X is hydrogen or methyl and
n is an integer from 1 to 10,000.

R ¹ and R ^{2 are} preferably hydrogen, (C ₁ -C ₄ ) alkyl, (C ₂ -C ₆ ) alkenyl or phenyl.

Under polymer II, amino radicals are to be understood as primary amino groups according to the IUPAC rules and not amido groups in which the NH ₂ radical is linked to a carbonyl radical. Accordingly, imino residue according to the IUPAC rules are to be understood as secondary amino groups (-NH-) and not imido groups in which the NHR residue is linked to a carbonyl residue.

As hydrogel-forming polymers II, the following amino and / or Iminorest-bearing polymers suitable by crosslinking were made water-insoluble. Preferred polymers are Polymers, copolymers and graft copolymers of "vinylamine" or Ethyleneimine, which can be polymer-analog modified.

• a) So-called polyvinylamines, i.e. polymers with the grouping -CH ₂ -CH (NH ₂ ) - as a characteristic building block, are accessible via polymer-analogous reactions. As such polymer-analogous reactions, those skilled in the art are, for example, the hydrolysis of poly-N-vinyl amides such as poly-N-vinyl formamide, poly-N-vinyl acetamide, of poly-N-vinyl imides such as poly-N-vinyl succinimide and poly-N-vinyl phthalimide and the Hofmann degradation of polyacrylamide when exposed to basic hypochlorite.

Polyvinylamines by polymerizing N-vinyl are preferred formamide and subsequent polymer-analogous reaction according to the DE-A-31 28 478. The molecular weight of the uncrosslinked Polyvi nylamins corresponds to a K value (determined according to H. Fikentscher in 1 wt .-% aqueous solution at 25 ° C) of 30-250.  

The polymers consisting of N-vinylformamide units can be by means of acidic, basic or enzymatic hydrolysis Hydrolysing the corresponding polyvinylamines. Is particularly preferred basic hydrolysis. In this way, degrees of hydrolysis are of 5 -95% available. Completely hydrolyzed are particularly preferred based products, d. H. maximum 100%, usually 95%. The The degree of hydrolysis is determined by enzymatic determination of the formate or by polyelectrolyte titration of the available amine functions NEN determined with potassium polyvinyl sulfate solution.

Crosslinked polyvinylamines are preferably used as polymers II sets that were previously desalinated. Desalted means that the salt content of low molecular weight salts (molecular weight < 500) ≦ 8% by weight based on the polymer. Desalination is, for example, by dialysis or ultrafiltration ren with a membrane of the exclusion limit 1000 D performed. The degree of desalination can be determined using gel permeation chromatography Check phie (GPC). Desalination is advantageous after polymer-analogous reaction and before the crosslinking reaction leads.

The desalted polymer solutions II are usually in ver thin solutions 2-10 wt .-% used for crosslinking.

As mentioned above, polymers II are preferred which are obtained by crosslinking tion of polyvinylamine with a K value of 30-250, preferred 50-230, especially 70-200, can be obtained. There with the high molecular weight polyvinylamines slow down crosslinking and possibly incomplete, poly are particularly preferred crosslinked vinylamines, which in the uncrosslinked state have a K value of Have 70-180.

Copolymers are suitable as further hydrogel-forming polymers II of "vinylamine", that is copolymers of, for example, vinyl form amide and comonomers by the polymera described above converted into formal copolymers of vinylamine be delt.

In principle, all monomers which can be copolymerized with vinylformamide are suitable as comonomers. The following monounsaturated monomers may be mentioned by way of example:
Acrylamide, methacrylamide, acrylonitrile, methacrylonitrile, vinyl acetate, vinyl propionate, styrene, ethylene, propylene, N-vinyl pyrrolidone, N-vinyl caprolactam, N-vinyl imidazole, monomers containing sulfone or phosphonate groups, vinyl glycol, acrylamido (methacryla mido) alkylene trialkyammon , Diallyl-dialkylammonium salts, (C ₁ -C ₄ ) alkyl vinyl ethers such as methyl vinyl ether, ethyl vinyl ether, isopropyl vinyl ether, n-propyl vinyl ether, t-butyl vinyl ether, N substituted alkyl (meth) acrylamides substituted by a (C ₁ -C ₄ ) alkyl group such as N -Methyl acrylamide, N-isopropylacrylamide and N, N-dimethylacrylamide as well as (C ₁ -C ₂₀ ) -alkyl (meth) acrylic acid esters such as methyl acrylate, ethyl methacrylate, propyl acrylate, butyl acrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxymethyl acrylate, hydroxypropyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, hydroxypropyl methacrylate, hydroxypropyl methacrylate, hydroxypropyl methacrylate, hydroxypropyl methacrylate, hydroxypropyl methacrylate, , 2-methylbutyl acrylate, 3-methylbutyl acrylate, 3-pentyl acrylate, neopentyl acrylate, 2-methylpentyl acrylate, hexyl acrylate, cyclohexyl acrylate, 2-et hylhexyl acrylate, phenyl acrylate, heptyl acrylate, benzyl acrylate, tolyl acrylate, octyl acrylate, 2-octyl acrylate, nonylacrylate and octyl methacrylate.

Specific copolymers should be mentioned in detail. So be z. B. DE-A-35 34 273 copolymers of N-vinylformamide with vinyl acetate, vinyl propionate, (C ₁ -C ₄ ) alkyl vinyl ether, methacrylic acid and acrylic acid esters, acrylonitrile and acrylamide and their homologues and vinyl pyrrolidone.

The concentration of the N-vinylformamide can be 10-95 mol% gene that of the comonomers 5-90 mol%.

Graft polymers of alkylene oxide units and N- Vinylformamide according to DE-A-195 15 943 after hydrolysis have been crosslinked as polymers II. Such graft polymers can be achieved by radical polymerization of N-vinylformamide in the presence of, for example, polyethylene glycols and subsequently producing basic saponification.

Other advantageous graft bases are polyvinyl acetate and / or polyvinyl alcohol. According to DE-A-195 26 626 this can Polymeric N-vinylformamide by radical polymerization be grafted and the polymer thus obtained hydrolyzed and on finally crosslinked to form polymers II.

Also copolymers are made of vinyl acetate, acrylic acid, methacrylic Acid, acrylamide and acrylonitrile suitable graft base for N- Vinylformamide. Furthermore, according to DE-A-41 27 733, mono-, Oligo and polysaccharides, which may be oxidative, enzyma table or hydrolytically degraded advantageous graft were for N-vinylformamide, the proportion by weight of which is 20 to 95% based on the total amount of monomer + graft base. These graft polymers are then hydrolysed into the converted free amines and finally crosslinked to polymers II.  

The graft polymers are preferred with N-vinylformamide as one ziges monomer formed. However, it is possible up to 50 wt .-% of N-vinylformamide by the above-mentioned comonomers of N-Vinylfor mamids to be replaced.

Furthermore, the polyvinylamines, their copolymers and graft copolymers modified by further polymer-analogous reactions his. These reactions are varied and can teach anyone book of organic chemistry such as B. "Advanced Organic Chemistry" by Jerry March, 3rd edition, John Willey & Sons 1985 become.

For the many possible reactions with primary amines here are some representative. In the presence of Formic acid or formic acid orthoesters react vicinal Ami nogroups of polyvinylamine to six-membered cyclic Amidines, as described, for example, in US Pat. No. 5,401,808. It may well be that some of the amino groups with vici nalen formamide groups reacted to cyclic amidine structures Has. Likewise, according to DE-A 43 28 975, copolymers made of acrylic nitrile, methacrylonitrile or their homologues, as well as acrylic and Methacrylic esters with N-vinylformamide in intramolecular condensates tion reactions during or after hydrolysis of the formamide group to the corresponding amino groups, with neighboring nitrile or carboxylic acid ester groups to the corresponding 2-amino-1-imidazoline or the corresponding γ-lactam structures react. The proportion of polymer-converted amino group can be up to 50 mol%.

In addition to these intramolecular, polymer-analogous reactions of Polyvinylamines are a variety of other such reactions possible. These include amidation, alkylation, sulfonamide bil dung, urea formation, thiourea formation, carbamate formation, Acylation with acids, lactones, acid anhydrides and acid chlorides, thiocarbamation, carboxymethylation, phosphono methylation, Michael addition to name a few. So here Posed polyvinylamine derivatives are also used in the manufacture of crosslinked polymers II. The are preferred polymer-analogous reactions before the crosslinking of the polyvinylamines, the copolymers and the graft copolymers of the "vinylamine" leads. The proportion of the amino groups reacted polymer analogously carries up to 50%, preferably 10 to 30 mol%, of the amino group pen of the polymer used. Through subsequent networking polymers obtained are preferred.  

• a) Furthermore, polyethyleneimines are grafted with ethyleneimine Polyamidoamines or grafted polyamines, which are reacted with α, β-unsaturated carboxylic acids, their esters or by the reac tion of formaldehyde with HCN or alkali metal cyanides (Strecker Reak tion) are modified.

Another class of amino groups, preferably polymers containing ethyleneimine units, is known from WO-A-94/12560. These are water-soluble, crosslinked, partially amidated polyethyleneimines, which are obtainable from

• - Reaction of polyethyleneimines with monobasic carboxylic acids or their esters, anhydrides, acid chlorides or acid amides with amide formation and
• - Implementation of the amidated polyethyleneimines with at least two Crosslinkers containing functional double bonds.

The molecular weights of the polyethyleneimines in question can amount to up to 2 million and are preferably in the range of 1000 to 50000. The polyethyleneimines are partially based carboxylic acids amidated so that, for example, 0.1 to 90, preferably 1 to 50% of the amidatable nitrogen atoms in the Polyethyleneimines is present as an amide group. Suitable, at least two crosslinkers containing functional double bonds are above called. Halogen-free crosslinkers are preferably used.

In the reaction of compounds containing amino groups with Crosslinkers are, for example, based on 1 part by weight of one Compound containing amino groups 0.1 to 50, preferably 1 up to 5 parts by weight of at least one crosslinker.

Other addition products containing amino groups, which after the Networking can be used as a component in superabsorbers are polyethyleneimines and quaternized polyethyleneimines. The Polyethyleneimines and the quaternized polyethyleneimines can optionally with at least two functional groups containing crosslinker be implemented. The Quaternization of Polyethyleneimines can, for example, with alkyl halides such as Methyl chloride, ethyl chloride, hexyl chloride, benzyl chloride or Lauryl chloride and made with, for example, dimethyl sulfate become. Other suitable polymers containing amino groups are polyethylene imines modified by the Strecker reaction, e.g. B. the reaction products of polyethyleneimines with formaldehyde and Sodium cyanide with hydrolysis of the resulting nitriles the corresponding carboxylic acids. These products can be given if with one containing at least two functional groups  Crosslinkers can be implemented or with themselves under amide Networking the formation and leakage of water.

Alkoxylated polyethyleneimines are also suitable for example by reacting polyethyleneimine with ethylene oxide and / or propylene oxide are available. The alkoxylated Polyethyleneimines are functional with at least two Crosslinker containing groups implemented and so water-insoluble made. The alkoxylated polyethyleneimines contain Group 0.1 to 100, preferably 1-3 alkylene oxide units. The Molecular weight of the polyethyleneimines can be up to two million gen. Poly is preferably used for the alkoxylation ethyleneimines with molecular weights from 1000 to 50000. Other suitable gnete water-soluble amino group-containing polymers are Um settlement products of polyethyleneimines with diketenes, e.g. B. from Polyethyleneimines with a molecular weight of 1000 to 50000 with distea ryldiketen, which are then networked.

Crosslinked polyethyleneimines are, for example, in EP 0895 521 described.

The polyethyleneimine is made in a conventional manner by cationic Polymerization in the presence of polymerization catalysts such as acids, Lewis acids, acidic metal salts or alkylation reagents polymerized. Polyethyleneimines with a Molecular Ge weight from 5000 to 5000000 (determined by sta statistical light scattering) are preferred to polymers II nets.

Crosslinker for the production of the hydrogel-forming polymers II are bi- or polyfunctional, that is, they have two or more active groups with the amino or imino residues of the Polymers can react. In addition to the low molecular weight crosslinkers can also use polymers and copolymers that are preferably water soluble are used as crosslinkers.

Suitable bifunctional or polyfunctional crosslinkers are, for example

• 1. Di- and polyglycidyl compounds
• 2. Di- and polyhalogen compounds
• 3. Compounds with two or more isocyanate groups, the bloc can be kiert
• 4. Polyaziridines
• 5. Carbonic acid derivatives
• 6. Connections with two or more activated double bin additions that can add Michael
• 7. Di- and polycarboxylic acids and their acid derivatives  
• 8. monoethylenically unsaturated carboxylic acids, their esters, Amides and anhydrides
• 9. Di- and polyaldehydes and di- and polyketones

Preferred crosslinkers (I) are, for example, those in the US-A-4144123 describes bischlorohydrin ethers of polyalkylene glycols. Furthermore, phosphoric acid diglycidyl ether and ethyl called lenglycoldiglycidylether.

Other crosslinkers are the reaction products of at least trihydric alcohols with epichlorohydrin to reaction products, which have at least two chlorohydrin units, e.g. B. are used as polyhydric alcohols glycerol, ethoxylated or propoxylated glycerols, polyglycerols with 2 to 15 glyces rin units in the molecule and optionally ethoxylated and / or propoxylated polyglycerols. Crosslinkers of this type are known for example from DE-A-29 16 356.

Suitable crosslinkers (2) are α, ω- or vicinal dichloroalkanes, for example 1,2 dichloroethane, 1,2 dichloropropane, 1,3-dichloro butane and 1,6-dichlorohexane.

Furthermore, EP-A-0 025 515 contains α, ω-dichloropolyalkylene glycols which are preferably 1-100, especially 1-100, ethylene oxide have known as crosslinkers.

Crosslinkers (3) which block blocked isocyanate Groups included, e.g. B. Trimethylhexamethylene diisocyanate bloc cated with 2,2,3,6-tetramethyl-piperidinone-4. Such crosslinkers are known, cf. for example from DE-A-40 28 285.

Crosslinkers containing aziridine units are also preferred (4) based on polyethers or substituted hydrocarbons fabrics, e.g. B. 1,6-bis-N-aziridinomethane, cf. US-A-3 977 923. In this class of crosslinkers still includes at least two aziridinos reaction products of dicarboxylic acid esters containing groups with ethyleneimine and mixtures of the crosslinkers mentioned.

Halogen-free crosslinkers of group (4) are reaction products which are esterified by reacting dicarboxylic acid and which are completely esterified with monohydric alcohols having 1 to 5 carbon atoms, with ethyleneimine. Suitable dicarboxylic acid esters are, for example, oxalic acid redimethyl ester, oxalic acid diethyl ester, succinic acid dimethyl ester, succinic acid diethyl ester, adipic acid dimethyl ester, adipate acid diethyl ester and glutaric acid dimethyl ester. For example, the reaction of diethyl oxalate with ethylene imine gives bis- [β- (1-aziridino) ethyl] oxalic acid amide. The dicarboxylic acid esters are reacted with ethyleneimine, for example in a molar ratio of 1 to at least 4. Reactive groups of these crosslinkers are the terminal aziridine groups. These crosslinkers can be characterized, for example, using the formula:

where n = 0 to 22.

Crosslinkers (5) are ethylene carbonate, propylene carbonate and urine fabric, thiourea, guanidine, dicyandiamide or 2-oxazolidinone and examples of its derivatives. From this group of Monomers are preferably propylene carbonate, urea and gua nidin used.

Crosslinkers (6) are reaction products of polyether diamines, Alkylene diamines, polyalkylene polyamines, alkylene glycols, poly alkylene glycols or their mixtures with monoethylenic unsaturated carboxylic acids, esters, amides or anhydrides mono ethylenically unsaturated carboxylic acids, the reaction pro products at least two ethylenically unsaturated double bonds, Carboxamide, carboxyl or ester groups as functional Have groups, as well as methylene bisacrylamide and divinyl sulfone.

Crosslinkers (6) are, for example, reaction products of poly ether diamines with preferably 2 to 50 alkylene oxide units, alkylene diamines such as ethylene diamine, propylene diamine, 1,4-diamino butane and 1,6-diaminohexane, polyalkylene polyamines with molecular weights <5000 z. B. diethylenetriamine, triethylenetetramine, dipropylenetriamine, tripropylenetetramine, dihexamethylenetriamine and aminopropylethylenediamine, alkylene glycols, polyalkylene glycols or mixtures thereof

• Monoethylenically unsaturated carboxylic acids,
• Esters of monoethylenically unsaturated carboxylic acids,
• - Amides of monoethylenically unsaturated carboxylic acids or
• - anhydrides of monoethylenically unsaturated carboxylic acids and  
• - methylene bisacrylamide.

These implementation products as well as their production are in the EP-A-873 371 and expressly as crosslinkers thinks.

Crosslinkers which are particularly preferred are those reaction products of maleic anhydride mentioned herein with α, ω-polyether diamines with a molecular weight of 400 to 5000, the conversion tion products of polyethyleneimines with a molecular weight of 129 to 50000 with maleic anhydride and the reaction products of Ethylene diamine or triethylene tetramine with maleic anhydride in the Molar ratio of 1: at least 2.

The compounds of the formula are preferably used as crosslinker (6)

in the X, Y, Z = O, NH
and Y additionally CH ₂
m, n = 0-4
p, q = 0-45000
mean,
which contain at least 2 carboxyl groups and are obtainable by reacting polyether diamines, ethylenediamine or polyalkylene polyamines with maleic anhydride or at least 2 Michael addition products containing ester groups from polyether diamines, polyalkylene polyamines or ethylenediamine and esters of acrylic acid or methacrylic acid each containing monovalent 1 to 4 carbon atoms Alcohol crosslinker (7).

Further halogen-free crosslinkers of groups (6), (7) and (8) are at least dibasic saturated carboxylic acids such as dicarboxylic acids and the salts, diesters and diamides derived therefrom. These compounds can, for example, using the formula

X-CO- (CH ₂ ) _n -CO-X

in which X = OH, OR ¹ , N (R ² ) ₂
R ¹ = C ₁ to C ₂₂ alkyl,
R ² = H, C ₁ -C ₂₂ alkyl and
n = 0 to 22
be characterized. In addition to the dicarboxylic acids of the above-mentioned formula, monoethylenically unsaturated dicarboxylic acids such as maleic acid or itaconic acid are suitable, for example. The esters of the dicarboxylic acids in question are preferably derived from alcohols having 1 to 4 carbon atoms. Suitable dicarboxylic acid esters are, for example, dimethyl oxalate, diethyl oxalate, diisopropyl oxalate, dimethyl succinate, diethyl succinate, diisopropyl succinate, di-n-propyl succinate, diisobutyl amide and adipate adipate, adipate adipate. Suitable esters of ethylenically unsaturated dicarboxylic acids are, for example, dimethyl maleate, diethyl maleate, diisopropyl maleate, dimethyl itaconate and diisopropyl itacon. In addition, substituted dicarboxylic acids and their esters such as tartaric acid (D, L-form and as a racemate) and tartaric acid esters such as tartaric acid dimethyl ester and tartaric acid di ethyl ester come into consideration.

Suitable dicarboxylic anhydrides are, for example, maleic acid anhydride, itaconic anhydride and succinic anhydride. Next There are crosslinking agents (7) as dimethyl maleate, maleic acid diethyl ester and maleic acid, for example, are suitable. The network tion of amino group-containing compounds with the foregoing The crosslinkers mentioned take place with the formation of amide groups or in the case of amides such as adipic acid diamide by transamidation. Malein acid esters, monoethylenically unsaturated dicarboxylic acids and their anhydrides can both by formation of carboxamide groups as well as by adding NH groups to crosslink the component (e.g. polyamidoamines) in the manner of a Michael Ad dition bring about networking.

To the at least dibasic saturated carboxylic acids of Ver Network class (7) includes, for example, tri- and tetracarbon acids such as citric acid, propane tricarboxylic acid, nitrilotriacetic acid acid, ethylenediaminetetraacetic acid, butanetetracarboxylic acid and Diethylenetriaminepentaacetic acid. As a crosslinker of the group (7) also come from the abovementioned carboxylic acids conducted salts, esters, amides and anhydrides z. B. tartaric dimethy  lester, tartaric acid diethyl ester, adipic acid dimethyl ester, adipine acid diethyl ester into consideration.

Suitable crosslinkers of group (7) are also polycarbonate acids produced by polymerizing monoethylenic unsaturated carboxylic acids, anhydrides, esters or amides are true. Comes as monethylenically unsaturated carboxylic acids men z. As acrylic acid, methacrylic acid, fumaric acid, maleic acid and / or itaconic acid. So are suitable as crosslinkers such. B. Polyacrylic acid copolymers of acrylic acid and methacrylic acid or copolymers of acrylic acid and maleic acid. As Comono mere its vinyl ether, vinyl formate, vinyl acetate and vinyl lactam mentioned as an example.

Other suitable crosslinkers (7) z. B. by radical polymerization of anhydrides such as maleic anhydride in an inert solvent such as toluene, xylene, ethylbenzene, isopropylbenzene or solvent mixtures. In addition to the homopolymeric copolymers of maleic anhydride come into consideration, for. B. copolymers of acrylic acid and maleic anhydride or copolymers of maleic anhydride and a C ₂ - to C ₃₀ olefin.

Preferred crosslinkers (7) are, for example, copolymers of maleic anhydride and isobutene or copolymers of maleic anhydride and diisobutene. The copolymers containing anhydride groups can optionally be modified by reaction with C ₁ -C ₂₀ alcohols or ammonia or amines and can be used in this form as crosslinking agents.

Preferred polymeric crosslinkers (7) are, for example, copolymers from acrylamide and acrylic esters, such as, for example, hydroxyethyl crylate or methyl acrylate being the molar ratio of acrylamide and acrylic esters can vary from 90:10 to 10:90. In addition to the Ter copolymers can also be used, where for example combinations of acrylamide, methacrylamide, acrylic esters or methacrylic esters can be used.

The molecular weight M _{w of} the homopolymers and copolymers is, for. B. up to 10,000, preferably 500 to 5000. Polymers of the type mentioned above are, for. B. described in EP-A-0 276 464, US-A-3 810 834, GB-A-1 411 063 and US-A-4 818 795. The at least dibasic saturated carboxylic acids and the polycarboxylic acids can also be in the form of the alkali - Or ammonium salts are used as crosslinkers. The sodium salts are preferably used. The polycarboxylic acids can be partially, e.g. B. 10 to 50 mol% or completely neutralized.

Crosslinkers (8) which are preferably used are acrylic acid and acrylic acid methyl ester, acrylic acid ethyl ester, acrylamide and methacrylamide.

Suitable halogen-free crosslinkers of group (8) are e.g. B. mono ethylenically unsaturated monocarboxylic acids such as acrylic acid, meth acrylic acid and crotonic acid and the amides, esters and anhydrides derived therefrom. The esters can be derived from alcohols having 1-22, preferably 1 to 18, carbon atoms. The amides are preferably unsubstituted, but can carry a C ₁ -C ₂₂ alkyl radical as a substituent.

It is of course also possible to use mixtures of two or two to use multiple networkers.

For the production of the superabsorbers according to the invention, ins particularly preferred those that are free of organically bound Ha are lied. Therefore, for the production of cross-linked polymers II, which are each insoluble in water, preferably halogen-free Crosslinker used.

The crosslinkers described above can be used either alone or in Mix in the reaction with water-soluble, amino groups ent polymers or polyalkylene polyamines are used. The crosslinking reaction is in all cases as far as ge leads to the fact that the resulting products are no longer water-soluble but are still swellable. The crosslinking reaction takes place by heating the reaction components at temperatures of Room temperature to 220, preferably at temperatures of 50-180 ° C. If the crosslinking reaction at temperatures above from 100 ° C in an aqueous medium, it is advantageous the resulting condensate (water, lower alcohols, ammonia, Amines together with the existing dilution water distill until the reaction mixture has solidified. The The polymer film is then comminuted and, if necessary, with cooling ground with dry ice in a coffee grinder.

Polymers II which do not have a crosslinker are also preferred were added, but because of their comonomers Are capable of self-networking. Such copolymers of vinyl form amides are thermally nachver after their hydrolysis nets.  

Comonomers suitable for self-crosslinking are acrylic acid esters, methacrylic acid esters and their homologues, and acrylamide and acrylonitrile.

For self-crosslinking, copolymers in particular are based suitable from acrylic, methacrylic acid esters or their homologues, but also those based on acrylic, methacrylic acid or their Homologues. The proportion of N-vinylformamide is usually between 50 and 99 mol%, that of the comonomers between 1 and 50 Mol%. A proportion of 5-15 mol% is particularly advantageous Comonomer content and 85-95 mol% as N-vinylformamide content where where the sum of the monomer proportions is always 100 mol%. Such co polymers are initially practical under basic conditions completely saponified, if necessary desalted and then crosslinked at temperatures of 80-220, preferably 120-180 ° C. Ge if necessary, the crosslinking of such copolymers by white accelerate teren addition of polyvinylamines or polyethyleneimines be inclined.

The ratios in which the two hydrogel-forming polyme Ren I and II are mixed together, next to each other their influencing factors primarily according to the density of the acid or Amine groups (val / g) and the acid or base strengths. Mix Ratios can range from 20: 1 to 1:20 (weight) vary. Mixing ratios between 10: 1 and 1:10, particularly preferably between 7: 3 and 3: 7.

Basically, the following options are available for producing the mixture:

• a) mixing the separately prepared powders,
• b) mixing the water-containing gels,
• c) mixing a water-containing gel with a powder,
• d) adding powders or gels of one component to Reaction mixture for the production of the other compo nente,
• e) Targeted formation of a bowl-shaped particle in the the core one component and the shell the other Component.
• f) All com commercially available units for mixing powders is suitable. The particle size of the particles to be mixed is  between 30 and 2000 µm, preferably between 100 and 850 µm. It Both components are the same as well to mix different particle sizes. The use of different particle sizes in both components be advantageous in that differences in Uptake rate or ion exchange rate of the two components can be coordinated can. It can also be advantageous to re a component to use relatively coarse and the other very fine, so the finely divided component on the surface of the coarser component is agglomerated. Possibly this process can be done by adding agglomeration aids means such as B. polyethylene glycols, water, polyols under be supported. Another option is from to use both components very fine powder and them with the addition of agglomeration aids as above listed to agglomerates with a size between 100 µm and 1500 µm to agglomerate. It can also be beneficial this Agglomeration with a surface post-crosslinking too combi kidneys, in such a way that post-crosslinking is also possible agglomeration causes. The advantage of agglomeration (regardless of which variant) it can be seen that In this way, particles are formed that contain both components together, so that when using these mixtures in e.g. B. hygiene articles no separation of the two components can kick. Especially when mixtures with very different Chen particle sizes of the two components are used this effect is pronounced. The separation of both components As a result, the ion exchange process takes a long time Diffusion paths have to be overcome that are too strongly acidic locally or basic pH values. This behavior is not acceptable for use in hygiene articles. Next agglomeration offers the advantage that high uptake speeds can be realized without much finely divided powders must be used because of their Dust generation is undesirable.
• g) Another possibility, the problem described above Avoiding component separation is to avoid the mix aqueous gels with each other and then connect them eats to dry and grind. Particles are obtained ten, which contain both components firmly bound together ten, so that a separation of the two components is not possible is. It is to be expected that the strong ionic interactions on both gel components build and so the basic and acidic components firmly together connect others (see DE-A-196 40 329). Training a  classic polyelectrolyte complex is not to be expected, since the two polyelectrolytes each in a separate network plant are involved. Since both components in their manufacture position as aqueous gels, it is advantageous for Mix these gels. But it is also possible Use gels that dry out by swelling with water products are obtained. Furthermore, it can also be done be involved in the manufacture of the components Partially dry the gels before they are mixed. The Mixing itself can be done with different equipment follow, such as B. meat grinders, kneaders, extruders, planet whale Zen extruder or mixer. The devices used must be one ensure homogeneous, fine-particle mixing of both components can afford without the network structure of the gels through strong shear damage. The water content of the mix ten gels is between 5 and 99.8% by weight, preferably between 60 and 99% by weight. The water content of the two mixed Gels can be the same or different. Advantageous In this variant, the fact that no se separate drying steps are required for both components and the gel mixtures obtained have a higher gel strength speed and thus easier handling.
• h) A limit case of variant b) represents the mixture of the gel one component with the powder of the other component. The procedure and the equipment used are the same as in case b). During the mixing process, the powder component, the gel component z. Dewater, so that this approach is the limit case of variant b) in the event that gels with extremely different Chen water contents are mixed. It is expected that in this case other structures within a party kels are obtained than in the event that gels with ver comparable water contents are mixed. In the latter Case the particles will have a structure in which the components side by side in comparable large domains available. The size relationships of the domains will be decided dend by the mixing ratio and the solids content of the gels used. In the former case, the component added in powder form an island structure in a matrix of the component used in gel form point. Depending on the desired range of properties, it can be be part of realizing one or the other structure ren.  
• i) Another way to get immiscible products come the addition of powders or gels to some Component to the reaction mixture of the other component. Care should be taken to ensure that there are no undesirable reaks expire. So z. B. with the addition of cross-linked Polyvinylamine to a reaction mixture of acrylic acid The crosslinker and initiator immediately see a Micheal addition between the primary amino groups of the gel and acrylic acid underway come. Provided that no unwanted Re actions can occur, it is possible to use the powder or also add a gel to the reaction mixture of the other component add to any point in the course of the reaction. This variant is expected to receive products the boundary layer between the components is one whose structure than in the case of gel or powder blends. At least one of the two components lies here partly still uncrosslinked, or even as a mixture of monomers in front. This allows more orderly in the boundary layer Structures with stronger interactions up to poly form electrolyte complexes and it is expected that the Boundary layer is significantly thicker than the previous one existing variants. This effect should improve gel stability heights and the achievable range of properties in the sense surface post-crosslinking.
• j) A variant of the method d) represents the production of a Core shell structure. Particles of one com component with a reaction mixture to produce the 2. Component coated, e.g. B. by spraying. After or during the reaction the core-shell product obtained dried. To achieve certain layer thicknesses it may be necessary to repeat the coating several times. On the other hand, it is also conceivable to use such a procedure also multi-layered particles with alternating Build up layers of the two components. To build one times, but especially complex layer structures especially a process control in a fluidized bed. The there is a major advantage of such a procedure in the fact that structures defined here with uniform and selectively adjustable layer thicknesses can be produced nen.

It may also be useful to add the mixtures described to be mixed with superabsorbers already on the market, d. H. add acidic or basic crosslinked polymers, their acidic or basic groups are neutralized to at least 50%. The  Share of these standard superabsorbents should be less than 50%, are preferably less than 25%.

In addition, the polymer I and II in known per se Post-crosslinked in an aqueous gel phase or as a dried, ge ground and sieved polymer particles post-crosslinked his.

In a preferred embodiment of the invention, the Absorp tion properties of the mixtures of polymers I thus obtained and polymers II by a subsequent surface improved even further. Here, an exclusive Crosslinking of the polymers I, an exclusive crosslinking of the Polymers II or, particularly preferably, a crosslinking of a ho homogeneous mixture of both types of polymer. To do this Compounds associated with the functional groups of the polymers can react with crosslinking, preferably in the form of a hydrous solution on the surface of the hydrogel particles upset. The water-based solution can be water-miscible contain organic solvents. Suitable solvents are Alcohols such as methanol, ethanol, i-propanol or acetone.

Suitable post-crosslinking agents are, for example

• - Di- or polyglycidyl compounds such as phosphonic acid diglyci dyl ether or ethylene glycol diglycidyl ether, Bischlorhydri ether of polyalkylene glycols,
• - alkoxysilyl compounds,
• - Compounds containing polyaziridines, aziridine units based on polyethers or substituted hydrocarbons substances, for example bis-N-aziridinomethane,
• - Polyamines or polyamidoamines and their implementation pro products with epichlorohydrin,
• - Polyols such as ethylene glycol, 1,2-propanediol, 1,4-butanediol, glycerol, methyltriglycol, polyethylene glycols with an average molecular weight M _w of 200-10000, di- and polyglycerol, pentaerythritol, sorbitol, the oxyethylates of these polyols and their esters with carboxylic acids or carbonic acid such as ethylene carbonate or propylene carbonate,
• Carbonic acid derivatives such as urea, thiourea, guanidine, Dicyandiamide, 2-oxazolidinone and its derivatives, bisoxa zoline, polyoxazolines, di- and polyisocyanates,
• - Di- or polyaldehydes such as glyoxal, succindi aldehyde or aldehyde starch,
• - Di- or polyketones
• - Connections with two or more activated double bin additions that can add Michael, like for example divinyl sulfone, methylenebisacrylamide or Ethylene glycol dimethacrylate,
• - Di- and polycarboxylic acids and their anhydrides, esters, Acid chlorides and nitriles such as oxalic acid, Glutaric acid, adipic acid, maleic anhydride, tatronic acid, Malic acid, tartaric acid or citric acid,
• - Di- and poly-N-methylol compounds such as Methylenebis (N-methylol methacrylamide) or melamine formal dehyde resins,
• - Di- and polyhalogen compounds such as α, ω-dichloropolyalkylene glycols, α, ω- or vicinal dichloroalkanes e.g. B. 1,2-dichloro ethane, 1,2-dichloropropane, 1,3-dichlorobutane or 1.6 Dichlorohexane,
• - Compounds with two or more blocked isocyanate groups such as trimethylhexamethylene diisocyanate blocked with 2,2,3,6-tetramethyl-piperidinone-4,
• - Monoethylenically unsaturated carboxylic acids, such as wise (meth) acrylic acid or crotonic acid, and their esters, Amides, and anhydrides.

If necessary, acidic catalysts such as p-toluene can be used olsulfonic acid, phosphoric acid, boric acid or ammonium dihydrogen phosphate can be added.

Particularly suitable post-crosslinking agents are di- or polygly cidyl compounds such as ethylene glycol diglycidyl ether, the implementation products of polyamidoamines with epichlorohydrin and 2-oxazo lidinone, which with both amino and carboxyl groups under Ver network can react.  

The crosslinking agent solution is preferably applied by application spray a solution of the crosslinker in reaction mixers or Mixing and drying plants. Suitable ones known to the person skilled in the art Mixing units for spraying the crosslinker solution onto the poly Mer particles are, for example, Patterson-Kelly mixers, DRAIS Turbulence mixer, Lödige mixer, NARA paddle mixer, Screw mixer, plate mixer, fluid bed dryer, Schugi Mixer (Flexo-Mix) or PROCESSALL. For crosslinking small Native quantities on a laboratory scale are suitable for kitchen mixers, such as accessories play a WARING blender. After spraying the crosslinker solution can follow a temperature treatment step, preferably in a downstream dryer, at a temperature between 80 and 230 ° C, preferably 80-190 ° C, and particularly preferably between 100 and 160 ° C, over a period of 5 minutes to 6 hours, preferably 10 minutes to 2 hours and particularly preferably 10 minutes grooves up to 1 hour, both fission products and solution middle parts can be removed. The drying can also take place in the mixer itself, by heating the jacket or Blowing in a preheated carrier gas.

In the case of the presence of particles, the structures are attached other adjacent domains or regions of polymers I and Po lymeren II, an additional networking of these Do man or area limits also by a temperature treatment done without adding a crosslinker. The water content of the par Particle before this temperature treatment is preferably 0 to 50% by weight, particularly preferably 1 to 30% by weight and most preferably 2 to 20% by weight. The temperature in this temperature step is between 80 and 230 ° C, preferably 80-190 ° C, and particularly preferably between 100 and 160 ° C, over a period of 5 minutes ten to 6 hours, preferably 10 minutes to 2 hours and in particular preferably 10 minutes to 1 hour. The temperature treatment after drying the particles in one step switched dryer take place, the desired water content the particles by spraying water or a mixture, consisting of water and one or more water miscible or ganic solvents. Preferably, the Temperature treatment step, however, when drying the hydro gel particles by first moving the hydrogel to a desired one dried water content and then the temperature undergoes treatment. The heat treatment can done in a separate dryer or preferably in the same Drying apparatus, which is also used to dry the hydrogel on the desired water content was used. Without a theory to be bound, the inventors believe that in this Temperature treatment at the domain or area boundaries Acid groups of polymer I with the amino groups of polymer II  Form covalent amide bonds, so that an additional Networking results.

In a particularly preferred embodiment of the invention, the hydrophilicity of the particle surface of the mixtures of polymers I and polymers II is additionally modified by the formation of complexes. The complexes are formed on the outer shell of the hydrogel particles by spraying on solutions of bivalent or multivalent metal salt solutions and / or bivalent or more anions, the metal cations with the functional groups of the anionic polymer and the multivalent anions can react with the functional groups of the cationic polymer to form complexes. Examples of divalent or polyvalent metal cations are Mg ²⁺ , Ca ²⁺ , Al ³⁺ , Sc ³⁺ , Ti ⁴⁺ , Mn ²⁺ , Fe ²⁺ / ³⁺ . CO ²⁺ , Ni ²⁺ , Cu ⁺ / ²⁺ , Zn ²⁺ , Y ³⁺ , Zr ⁴⁺ , Ag ⁺ , La ³⁺ , Ce ⁴⁺ _, Hf ⁴⁺ , and Au ⁺ / ³⁺ , preferred metal Cations are Mg ²⁺ , Ca ²⁺ , Al ³⁺ , Ti ⁴⁺ , Zr ⁴⁺ and La ³⁺ , and particularly preferred metal cations are Al ³⁺ , Ti ⁴⁺ and Zr ⁴⁺ . Examples of divalent or polyvalent anions are sulfate, phosphate, borate and oxalate. Of the metal cations mentioned and the polyvalent anions mentioned, all salts are suitable which have sufficient solubility in the solvent to be used. Water, alcohols, DMF, DMSO and mixtures of these components can be used as solvents for the salts. Water and water / alcohol mixtures such as water / methanol or water / 1,2-propanediol are particularly preferred.

Spraying the salt solution onto the particles of the mixture hydrogel-forming polymers I and II can be both before and after the surface post-crosslinking of the particles. In a particularly preferred method is used to spray the Salt solution in the same step with spraying the crosslinker Solution, where both solutions are separated one after the other or the same are sprayed on in time via two nozzles, or crosslinker and Salt solution can be sprayed together via a nozzle.

Optionally, a further modification of the particles of the mixture of polymers I and polymers II can be carried out by admixing finely divided inorganic solids, such as, for example, silica, bentonite, aluminum oxide, titanium dioxide and iron (II) oxide, which further enhances the effects of surface treatment . The addition of hydrophilic silica or of aluminum oxide with an average size of the primary particles of 4 to 50 nm and a specific surface area of 50-450 m ² / g is particularly preferred. The admixture of finely divided inorganic solids is preferably carried out after the surface modification by crosslinking / complex formation, but can also be carried out before or during these surface modifications.

In a number of process steps it can be useful to use additives. Additives in the sense of the present inventions are finely divided, powdery or fibrous substances which are inert to the manufacturing conditions of the components and the mixtures and which can be organic or inorganic in nature. Examples of such additives are:
Finely divided silicon dioxide, pyrogenic silicas, precipitated silicas in hydrophilic or hydrophobic modifications, zeolite, titanium dioxide, zirconium dioxide, talc, bentonites of all kinds, cellulose, silicates of all kinds, guar gum, tarakum flour, Johan nisbrot kernel flour, all types of starches, calcium, barium sulfate sulfate .

They can be used both as process aids and as carriers Find material use.

To handle in the preparation of mixtures according to the invention the gels are all sticky in more or less pronounced form rig. In order to overcome this disadvantage, it can be used especially in the Zer smaller, be useful when mixing or drying 0.1 to 10 wt .-% of one or a combination of several of the above Add additives before or during the process step. This measure makes the surface of the gels fine partial additive and thus reduces the stickiness or at least drastically reduced. This addition also has an effect on the properties of the end product. Because the ge dried powder particles on the surface with the additive the flowability of the powders obtained is verified improves. Furthermore, the dried gels tend to in contact with damp atmosphere, absorb water and thereby sticking. The addition of the above additives also reduces this sticking effect. Therefore, it can make sense be to add such additives to the end product. This is the case if they are in the previous process steps are not needed.

To increase the surface area, to reduce diffusion pathways and around the functional groups of the gels To make it accessible, it may make sense to use the above to produce acidic or basic gels on a support. A sol cher carrier must therefore have a large specific surface point. The additives mentioned above have this property on, especially pyrogenic silicas, bentonites and talc  are preferred. For the preparation of such acidic or basic Components can be the carrier material in the production of the com components are simply added to the reaction mixtures. As Alternatively, there is the possibility of the carrier material aims to coat with the reaction mixture z. B. by Auf spray in a fluidized bed. The amount of carrier used material ranges between 5% and 80%. Can continue Surfactants and blowing agents are used as auxiliaries.

The following test methods were used to study the polymer mixtures according to the invention used:

CRC (Centrifuge Retention Capacity)

To determine the CRC I, 0.2 g of polymer powder (grain fraction 106-850 µm) weighed into a 60 × 85 mm tea bag, the is then welded. The tea bag is then placed in one Excess 0.9% by weight saline solution (at least 0.83 l saline solution / 1 g polymer powder). After 30 minutes The tea bag is taken out of the saline solution and swelling time Centrifuged at 250 g for three minutes. By weighing the zen centrifuged tea bags is held tight by the polymer powder determined amount of liquid.

PUP 0.7 psi (Performance Under Pressure 0.7 psi)

The test method for determining the PUP 0.7 psi (pound / square inch, 0.7 psi = 4826.5 Pa) is used in U.S. 5,599,335 ben.

PUP 1.4 psi (Performance Under Pressure 1.4 psi)

The PUP 1.4 psi is determined in the same way as the PUP 0.7 psi, but under a weight load of 1.4 psi (9653 Pa).

PUP 0.014 psi (Performance Under Pressure 0.014 psi)

The PUP 1.4 psi is determined in the same way as the PUP 0.7 psi, but under a weight load of 0.014 psi (96.5 Pa), i.e. H. without weight, only with the plastic insert for that Weight.

SFC (Saline Flow Conductivity)

The test method for determining the SFC is described in U.S. 5,599,335 described.

SFC Index (Saline Flow Conductivity Index)

The SFC index is obtained from three SFC measurements with different weight loads using the following formula:

SFC index = [SFC (0.3 psi). 10 ⁷ g / cm ³ s]. [SFC (0.6 psi). 10 ⁷ g / cm ³ s] + [SFC (0.9 psi). 10 ⁷ g / cm ³ s]

The SFC (0.3 psi) corresponds to the SFC (0.3 psi = 2068.5 Pa). The SFC (0.6 psi) swells the Hydrogels and the flow measurement under a weight load of 0.6 psi (4137 Pa), with the SFC (0.9 psi) the swelling takes place and flow measurement at a weight load of 0.9 psi (6205.5 Pa).

PAI (NaCl) (Pressure Absorbency Index (NaCl))

The Pressure Absorbency Index (NaCl) is determined in accordance with the description of the PAI test method in EP-A-0 615 736, with the difference of a measuring time extended up to 16 hours.

PAI (Jayco) (Pressure Absorbency Index (Jayco))

The determination of the Pressure Absorbency Index (Jayco) is carried out analogously to the determination of the Pressure Absorbency Index (NaCl) described above, but the liquid to be absorbed is, however, a synthetic urine replacement solution with the following composition: 1000 g distilled water, 2.0 g KCl , 2.0 g Na ₂ SO ₄ , 0.85 g (NH ₄ ) H ₂ PO ₄ , 0.15 g (NH ₄ ) ₂ HPO ₄ , 0.19 g CaCl ₂ , 0.23 g MgCl ₂ .

Diffusing Absorbency Under Pressure

The method for determining the diffusing absorbency under pres sure is carried out analogously to the description in EP-A-0712 659, but with the following modifications: the weight of polymer is 0.9 g instead of 1.5 g; the polymer sample is measured in the grain size range 106-850 µm; the weight load on the measurement is 0.7 psi (4826.5 Pa) instead of 0.3 psi (2068.5 Pa); the residual solution is a synthetic urine replacement solution with the following composition: 1000 g distilled water, 2.0 g KCl, 2.0 g Na ₂ SO ₄ , 0.85 g (NH ₄ ) H ₂ PO ₄ , 0.15 g (NH ₄ ) ₂ HPO ₄ , 0.19 g CaCl ₂ , 0.23 g MgCl ₂ instead of 0.9% by weight saline; the measuring time be 4 h instead of 1 h.

Wicking performance

The wicking performance is measured ana log for measuring the wicking parameter as in the EP-A-0 532 002. Deviating from the measurement of the Wic The king parameter is the measurement of wicking performance with 2 g Polymer (grain size distribution 106-850 µm) only with a pre degree of swelling of 10 g 0.9% by weight NaCl solution / 1 g polymer guided. The wicking distance, which indicates the wel length of the polymer particles after a test time of 1 h the blue colored test liquid is swollen and the wic king-capacity, that of the additionally added during this time Corresponds to the amount of liquid.

Acquisition Time / Rewet under pressure

The examination is carried out on so-called laboratory pads. To produce these laboratory pads, 11.2 g of cellulose fluff and 23.7 g of hydrogel are swirled homogeneously in an air chamber and placed on a 12 × 26 cm mold by applying a slight negative pressure. This composition is then wrapped in tissue paper and pressed twice at a pressure of 20 bar for 15 seconds. A laboratory pad manufactured in this way is attached to a horizontal surface. The center of the pad is determined and marked. Synthetic urine replacement solution is applied through a plastic plate with a ring in the middle (inner diameter of the ring 6.0 cm, height 4.0 cm). The plate is loaded with additional weights so that the total load on the pad is 13.6 g / cm ² . The plastic plate is placed on the pad so that the center of the pad is also the center of the feed ring. It is given three times 80 ml synthetic urine replacement solution. The synthetic urine replacement solution is prepared by dissolving 1.14 g of magnesium sulfate heptahydrate, 0.64 g of calcium chloride, 8.20 g of sodium chloride, 20 g of urea in 1 kg of deionized water. The synthetic urine replacement solution is measured in a measuring cylinder and applied in one shot through the ring in the plate to the pad. Simultaneously with the task, the time is measured which is necessary for the solution to penetrate completely into the pad. The measured time is noted as Acquisition Time 1. The pad is then loaded with a plate for 20 minutes, the load being kept at 13.6 g / cm ² . After this time the plate is removed, 10 g ± 0.5 g of the filter paper (Schleicher & Schuell, 1450 CV) are placed on the center and with a weight (area 10 × 10 cm, weight 3.5 kg) for 15 s charged. After this time, the weight is removed and the filter paper is weighed back. The difference in weight is noted as Rewet 1. Then the plastic plate with the feed ring is placed on the pad again and the second application of the liquid takes place. The measured time is noted as Acquisition Time 2. The procedure is repeated as described, but 45 g ± 0.5 g filter paper is used for the Rewet examination. The Re wet 2 is noted. The same procedure is used to determine acquisition time 3. When determining Re wet 3, 50 g ± 0.5 g filter paper are used.

RAC factor (re-absorbing capacity factor of sheared gel)

For the determination (generally double determination) of the RACF, 1.2 g of polymer in an aluminum dish (diameter 4 cm, edge height 3 mm) are mixed with 12.0 g of 0.9% by weight NaCl solution and allowed to swell for 30 minutes, whereby during this time the sample is covered to protect it from drying out. 1.10 g of the pre-swollen gel are weighed into a plexiglass cylinder (inner diameter = 25 mm, height 33 mm) with a 140 μm sieve bottom and covered with a plexiglass disc. The cylinder with substance and disc is weighed, the weight registered as W1. The plexiglass disc is then loaded with a metal weight (plexiglass disc + weight = 245 g, which corresponds to a pressure of 50 g / cm ² or 4905 Pa) and the entire measuring unit is placed in a 13 ml 0.9% by weight NaCl - Solution filled Petri dish (diameter = 100 mm, height = 10 mm). After 60 minutes of swelling, the measuring unit is lifted out of the Petrichale, the weight is removed, excess saline solution adhering to the sieve bottom is stripped off and the measuring cell is weighed back with swollen gel and plexiglass disk, the weight is registered as W2. The rest (11 g) of the pre-swollen gel after removal of the amount of gel for the previously described double determination is transferred to a polyethylene bag measuring 30 × 150 mm and the open side of the bag is vacuum-sealed. The bag is fixed on a foil bag tester with an adhesive strip and then subjected to a roll-down test, which means that it is rolled over 50 times with a roll of 2 kg (yes 25 times in the opposite direction). The resulting mechanically loaded gel is now used in the same way as previously described for absorption under a pressure load of 50 g / cm ² (re-absorbing capacity of sheared gel). The weight of the measuring cell with gel and disk before the 60 minute absorption is recorded as W3, the weight after absorption as W4. The re-absorbing capacity factor is now understood to be the ratio of absorption after absorption before shear of the gel, multiplied by 100:

RAC factor = [(W4 - W3) / weight of gel sheared / 10)]. 100 / [(W2 - W1) / (initial weight gel unsheared / 10)]

DATGLAP 0.7 psi / 0.9 psi (Demand Absorb xy Through Gel Layer Against Pressure 0.7 psi / 0.9 psi)

The method for determining DATGLAP is divided into two stages. In the first stage, an AUL (Absorption Under Load) is measured under a weight load of 0.7 psi (0.7 psi = 4826.5 Pa), for which purpose the same measuring cell and the same equipment are used and the procedure is almost identical to that in determining the PUP 0, 7 psi, the method of which is described in US Pat. No. 5,599,355. However, the DATGLAP / level 1 differs from the PUP in two points:

• 1. After sprinkling the test substance on the sieve bottom of the A Plexiglas (outer diameter = 5.98 cm so that it is in the measuring cell without jamming / tilting Swelling of the gel can be moved up / inside diameter = 4.9 cm / thickness = 0.32 cm), covered with smooth chem sieve cloth as the bottom of the measuring cell, placed, and in such a way that the ring with its covering a through smooth surface gives off upwards while downwards towards the bottom of the measuring cell in the area of the inner ring knife quasi at a height of 0.32 cm a chamber between between the two sieve tensions. On the string The plastic cover plate is then weighted poses.
• 2. As a test solution at DATGLAP, no synthetic one is used Urine but 0.9% saline is used.

After a med period of 1 hour, a new measuring unit of the same type as before is written (but smaller in diameter to the Plexiglaszylin) on the remaining plexiglass ring remaining in the measuring cell and resting on the gel after removing the weight and the plastic cover plate to fit from the first measuring stage), set and leave for 4 hours. The measurement of the liquid absorption begins again when the second measuring unit is placed on the sieve ring of the first measuring unit. The second measuring cell has the following dimensions: outer diameter = 5.98 cm / inner diameter = 5.03 cm. The test substance distributed on the sieve bottom of the second measuring cell is covered beforehand with a plexiglass disk (5.018 cm diameter) and loaded with a weight (plexiglass plate + weight = 1331 g → 67.3 g / cm ² = 6606 Pa).

DATGLAP = (DAAP-TGL / DAAP regulator). (DAAP-Regular + DAAP-TGL) [g / g]

DAAP-TGL = Demand Absorbance Against Pressure Through Gel Layer after 4 hours, in [g / g] = measured value from 2nd stage with 2nd measuring cell
DAAP-Regular = Demand Absorbance Against Pressure after 1 hour, in [g / g] = measured value from 1st stage with 1st measuring cell

Polymer mixtures with an SFC index of minimum are preferred at least 10,000, preferably ≧ 100,000, in particular ≧ 200,000 and particularly preferred ≧ 300000.

Furthermore, are especially for use in hygiene articles Polymer mixtures with a Pressure Absorbency Index (NaCl) of ≧ 100, preferably ≧ 130, especially ≧ 150 and especially before moves ≧ 180 after a swelling time of 16 h, preferably 4 h, suitable.

In particular, polymer mixtures are preferred which have a Pres sure Absorbency Index (Jayco) of at least 150, preferably ≧ 200, in particular ≧ 225 and particularly preferably from ≧ 250 to have a swelling time of 16 h, preferably 4 h.

In addition, polymer mixtures with a diffusing absorber bency Under Pressure of at least 30 g / g preferred ≧ 40 g / g, m in particular ≧ 45 g / g and particularly preferably ≧ 50 g / g advantage arrested.

Polymer mixtures which are in the wicking perforation are also advantageous mance test a wicking distance of at least 5 cm, preferred 8 cm, in particular ≧ 10 cm and particularly preferably ≧ 15 cm and a wicking capacity of at least 5 g, preferably ≧ 8 g, ins have particular ≧ 10 g, particularly preferably ≧ 13 g.

Polymer mixtures which are in the acquisition are also preferred Time / Rewet under pressure test an acquisition time 3 of at most 25 s, preferably ≦ 20 s, in particular ≦ 15 s, very particularly ≦ 10 s and a rewet 3 of at most 9 g, preferably ≦ 5 g, ins particularly ≦ 3 g and particularly preferably ≦ 2 g.

Polymer mixtures which have a RAC factor of at least 80, preferably ≧ 90, in particular ≧ 100 and especially preferably have from ≧ 120.  

In addition, polymer mixtures with a DATGLAP of minde at least 50 g / g, preferably ≧ 65 g / g, in particular ≧ 80 g / g and whole particularly preferred vorteilhaft 90 g / g advantageous.

In particular, polymers are preferred which prefer several of these have properties. So polymer blends with one SFC index ≧ 10,000 and a wicking distance of ≧ 5 cm and a wicking capacity of at least 5 g is preferred. Especially polymer mixtures with an acquisition time 3 are preferred of at most 25 s and a rewet 3 of at most 9 g and one SFC ≧ 10,000 and / or a diffusing absorbance under pressure from ≧ 30 g / g. Polymer mixtures are very particularly preferred with an SFC index of ≧ 1000, a PAI of ≧ 150 after one Swelling time of 16 h, a diffusing absorbance under pressure of at least 30 g / g, a wicking distance of ≧ 5 cm, a wic king capacity of ≧ 5 g, an acquisition time 3 of at most 25 s and a rewet 3 of maximum 9 g.

Polymer mixtures with polymers I based are preferred Acrylic acid and / or methacrylic acid.

Polymer mixtures are preferred whose polymer I ver is polyacrylic acid, whose carboxylic acid groups from 0 to 50% are present as an alkali or ammonium salt.

Polymer mixtures with crosslinked copo are also preferred lymer from acrylic acid or methacrylic acid with vinylsulfonic acid or acrylamidopropanesulfonic acid as polymer I.

Polymer mixtures in which the Polymers I with oligo- or polyethylene glycol diacrylates or cross-linked methacrylates with molecular weights of 200 to 1000 were.

Polymer mixtures whose polymer II is a poly are preferred ethyleneimine, an ethyleneimine-grafted polyamide amine, and / or is grafted polyamine that are cross-linked.

Polymer mixtures whose polymer II is also preferred cross-linked polyvinylamine.

Polymer mixtures whose polymer II is preferred are also preferred Copolymerization of vinyl formamide and one or more mono ethylenically unsaturated compounds, subsequent hydrolysis and optionally desalting and subsequent crosslinking has been.  

Polymer mixtures whose polymer II is a graft are preferred copolymer of vinylformamide on polymeric compounds is that then hydrolyzed, optionally desalted and crosslinked has been.

Polymer mixtures whose polymer II is preferred Copolymer of vinyl formamide and monoethylenically unsaturated Mono- and / or polycarboxylic acids, which is then hydroly If necessary, desalinated and crosslinked by heating, the means without the addition of crosslinker.

Polymer mixtures whose polymer II is preferred Copolymer of vinyl formamide and monoethylenically unsaturated Mono- and / or polycarboxylic acids that hydrolyze is given if desalted, cross-linked by heating and then with a cationic polymer or copolymer based on poly vinylamine or polyethyleneimine and / or with at least one bifunctional networkers can be further networked.

Polymer mixtures whose polymer II is also preferred olyethlenimine, a polyamidoamine grafted with ethyleneimine or a polyamine is that by reaction with α, β-unsaturated car bonic acids, their esters or by Strecker reaction polymerana log was modified and then thermally crosslinked.

Polymer mixtures whose polymer II is preferred are also preferred Crosslinking of a polyvinylamine with a K value of 40 to 220, in particular 70 to 160 were obtained.

Polymer mixtures whose polymer II is also preferred one or more crosslinkers of groups (1), (5), (6), (7), (8) and (9) was made.

Polymer mixtures with a ratio of acid are preferred residues to the sum of amino / imino residues from 2: 1 to 1: 8.

Polymer mixtures which are produced by mixing Polymer gel I and polymer gel II can be obtained.

Polymer mixtures which are produced by mixing are particularly preferred of polymer gel I and polymer powder II or of polymer powder I and polymer gel II can be obtained.

Polymer mixtures which are produced by addition are particularly preferred a mixture component I or II as a powder in the reaction mixture of the other component can be obtained.  

Polymer mixtures which contain polymer powder I, Contain polymer powder II and agglomeration aids.

Polymer mixtures which are preferred after mixing the Polymers I and II are post-crosslinked. The hereby obtained intraparticular mixtures with a domain structure structure, island structure and / or core-shell structure are preferred.

Polymer mixtures which have an agglomeration are also preferred cured, post-crosslinked powder mixture.

The polymer mixtures according to the invention have good application technical characteristics. You have an advantageous SFC Index, good PAI values as well as for table salt as well Jayco. They also show excellent diffusing absorbency Under pressure. They also score in the wicking performance test good results. Of particular note are their good ones Values in the Acguisition Time / Rewet test under pressure.

The following examples are intended to illustrate the invention without it to restrict.

example 1 a) Preparation of a cross-linked polyacrylic acid

350 g (4.86 mol) of acrylic acid together with 3.84 g of poly ethylene glycol diacrylate of a polyethylene glycol the mole mass 400 and 0.88 g sodium peroxodisulfate in 1046.16 g de still water dissolved. The solution is at room temperature transferred to a 2 liter dewar. The Dewar comes with a Plug closed, the one gas outlet and one to the Bottom-reaching gas inlet pipe carries. Through the gas nitrogen is passed through the inlet tube for 30 min to remove dissolved oxygen. Then 2.92 g a 0.3 wt .-% ascorbic acid solution as a coinitiator added and homogeneous by a strong stream of nitrogen mixed in. After the polymerization has started, the Turned off nitrogen flow and the gas inlet tube from the Dewar pulled out. After an overnight reaction, a Mash part of the gel block obtained in a meat grinder and in a vacuum drying cabinet at 85 ° C overnight in a Va vacuum dried. The second part was without additional loading used for further experiments. The dried gel was ground and the fraction with a particle size between sieved 100 µm and 850 µm.  

b) Preparation of a crosslinked with ethylene glycol diglycidyl ether Polyvinylamine

2241 g of a 12.3% by weight aqueous polyvinylamine solution (K value 85) become homogeneous at room temperature with a Solution of 13.77 g ethylene glycol diglycidyl ether in 100 g least Mixed water. Then the mixture is in heated to 75 ° C for 2 hours in a water bath. Part of the the gel obtained is used directly for further experiments, the rest is dried at 85 ° C. and vacuum overnight. The the product obtained is ground and the fraction with a Particle size between 100 microns and 850 microns sieved.

c) Preparation of the powder mixture

10 g each of the sieved powders obtained according to a) and b) products were mixed homogeneously.

Example 2 Preparation of a gel-gel mixture

86.40 g of undried poly produced according to Example 1a) acrylic acid gel and 157.30 g of undried material according to Example 1b) posed polyvinylamine gel are thereby intimately ge together mixes that 3 times together by a commercial Meat grinder to be rotated. The gel mixture obtained is over Dried in a vacuum at 85 ° C. overnight. After grinding, the Fraction with a particle size between 100 microns and 850 microns abge seven.

Example 3

64.8 g of undried polyacrylic prepared according to Example 1a) acid gel and 183.5 g of undried material prepared according to Example 1b) tes polyvinylamine are mixed intimately, that they go together 3 times through a commercial meat grinder be rotated. The gel mixture obtained is at overnight 85 ° C dried in vacuo. After grinding, the fraction is with sieved a particle size between 100 microns and 850 microns.

Example 4

100 g of a 12.5% by weight aqueous polyvinylamine solution (K- Value 85) and a solution of 0.63 g of ethylene glycol diglycidyl ether in 4.38 g dist. Water are homogenized at room temperature mixes. Then 12.5 g of the according to Example 1a) are obtained  made powdery, cross-linked polyacrylic acid by strong Stirring also mixed homogeneously. The reaction mixture is heated to 75 ° C in a water bath for 2 hours. The received Gel is crushed, dried at 85 ° C and vacuum overnight, ground and the fraction with a particle size between 100 microns and sieved 850 µm.

Example 5

• a) 100 g of a 13.6% by weight aqueous polyvinylamine solution (K value 85) and a Lö 19320 00070 552 001000280000000200012000285911920900040 0002019917919 00004 19201 solution of 0.41 g of N, N'-methylene bisacrylic amide in 9.93 g dist. Water become homogeneous at room temperature mixed. The reaction mixture is in water for 2 hours bath heated to 75 ° C. The gel obtained is crushed at 85 ° C and vacuum dried overnight, ground and the frak tion with a particle size between 100 µm and 850 µm seven.
• b) 10 g each of the sieved powder products from the examples 1a) and 5a) were mixed homogeneously.

Example 6

• a) 100 g of a 37.4% by weight aqueous polyethyleneimine solution (MW approx. 500000) becomes homogeneous at room temperature with 2.99 g Ethylene glycol diglycidyl ether mixed. Then the Mixture warmed to 75 ° C in a water bath for 2 hours. Part of the gel obtained is used directly for further experiments used, the rest is ge at 85 ° C and vacuum overnight dries. The product obtained is added with Troc keneis ground and the fraction with a particle size between sieved 100 µm and 850 µm.
• b) 10 g each of the sieved powder products from the examples 1a) and 6a) were mixed homogeneously.

The advantageous application properties of inventive polymer mixtures of Examples 1-6 are in Table 0 compiled.  

Example 7

• a) In a well insulated by foamed plastic material Polyethylene container with a capacity of 10 l 3450 g of deionized water and 1400 g of acrylic acid submitted. 14 g of allyl methacrylate are added to this solution with stirring add and inertize the solution by passing stick material. At a temperature of approx. 10 ° C the initiato ren, consisting of 0.57 g of 2,2'-azobisamidino propane dihydroch loride, dissolved in 50 g deionized water, 69 mg water peroxide, dissolved in 50 g of deionized water and 27 mg ascorbic acid, dissolved in 50 g deionized water, added and stirred in succession. The reaction solution is then left standing without stirring, being by the onset Polymerization, in the course of which the temperature reaches approx. 92 ° C increases, a firm gel is formed.
• b) 1000 g of a 6% by weight aqueous polyvinylamine solution (K- Value 137) and a solution of 4.8 g methylenebisacrylamide in 240 ml of deionized water become homo at room temperature gene mixed. The reaction mixture is then without Stir for 6 h at 80 ° C, taking a firm gel will hold.
• c) The two gels are mechanically crushed and the comminuted gels are in a ratio of 1: 1, based on the Solids content of the gels, by repeated common Wol fen mixed together. The mixed gel is in a vacuum drying cabinet at 80-100 ° C dried, ground and at 106-850 µm sieved.

The product has the following properties:
PUP 0.014 psi = 55.2 g / g after 240 min
PUP 0.7 psi = 51.4 g / g after 240 min
PUP 1.4 psi = 41.7 g / g after 240 min
CRC = 20.7 g / g
SFC = 1055 x 10 ⁷ cm ³ s / g

SFC index

SFC (0.3 psi) = 1055 x 10 ^-7

cm ³

s / g
SFC (0.6 psi) = 315 x 10 ^-7

cm ³

s / g
SFC (0.9 psi) = 47 x 10 ^-7

cm ³

s / g
SFC Index = 378745

PAI (NaCl)

AUL 0.01 psi = 43.8 g / g after 240 min
AUL 0.29 psi = 41.6 g / g after 240 min
AUL 0.57 psi = 37.9 g / g after 240 min
AUL 0.90 psi = 34.9 g / g after 240 min
PAI = 158.2
AUL 0.01 psi = 50.3 g / g after 16 h
AUL 0.29 psi = 47.8 g / g after 16 h
AUL 0.57 psi = 44.2 g / g after 16 h
AUL 0.90 psi = 40.7 g / g after 16 h
PAI = 183.0

PAI (Jayco)

AUL 0.01 psi = 63.6 g / g after 240 min
AUL 0.29 psi = 58.1 g / g after 240 min
AUL 0.57 psi = 55.3 g / g after 240 min
AUL 0.90 psi = 52.9 g / g after 240 min
PAI = 229.9
AUL 0.01 psi = 70.4 g / g after 16 h
AUL 0.29 psi = 64.8 g / g after 16 h
AUL 0.57 psi = 61.9 g / g after 16 h
AUL 0.90 psi = 58.3 g / g after 16 h
PAI = 255.4
Diffusing Absorbency Under Pressure = 51.6 g / g
Wicking Performance: Wicking Distance = 11 cm
Wicking Capacity = 13.1 g

Acquisition Time / Rewet under pressure

Acquisition time 1 = 38 s
Acquisition time 2 = 32 s
Acquisition time 3 = 13 s
Rewet 1 <0.1 g
Rewet 2 <0.1 g
Rewet 3 <1.4 g
RAC factor = 101
DATGLAP = 86.2 g / g

Production of surface post-crosslinked polymer I Base polymer gel A

8.0 kg of pure acrylic acid are added to a 40 l plastic bucket Diluted 24 kg of water. 37 g (0.457  Wt .-%, based on acrylic acid) pentaerythritol triallyl ether with stirring, and inertizes the closed bucket by passing nitrogen through it. The polymerization is then by adding 4 g of 2-2'-azobis-amidinopro-dihydrochloride, ge dissolves in 100 ml of water, 460 mg of hydrogen peroxide and 170 mg Ascorbic acid, also dissolved in 100 ml of water, star tet. Approx. 3 hours after the reaction has ended, the gel is me chanically crushed.

Polymer A0

The base polymer gel A is at 50 ° C under vacuum in a drying cabinet dried, ground in a coffee grinder, and finally at 100-800 µm sieved.

Polymer A1

The polymer gel A0 is crosslinked in a Waring laboratory mixer sprayed zer solution of the following composition: 2.5% by weight 1,2-propanediol, 2.5% by weight water, 0.2% by weight ethylene glycol digly cidyl ether, based on the polymer used. Then will the moist product at 120 ° C for 120 minutes in a circulating air dryer cabinet annealed. The dried product is abge at 850 microns sieves to remove lumps.

Polymer A2

The basic polymer gel A is mixed with as much sodium hydroxide solution until a degree of neutralization of 10 mol%, based on the one used Acrylic acid. The partially neutralized gel will then dried, ground, sieved and post-crosslinked.

Polymer A3

The base polymer gel A is mixed with as much sodium hydroxide solution until a degree of neutralization of 20 mol%, based on the one used Acrylic acid. The partially neutralized gel will then analogous to the production of polymer A1 dried, ground, ge sieves and cross-links.

Polymer A4

The base polymer gel A is mixed with as much sodium hydroxide solution until a degree of neutralization of 30 mol%, based on the one used Acrylic acid. The partially neutralized gel will then analogous to the production of polymer A1 dried, ground, ge sieves and cross-links.

Polymer A5

The base polymer gel A is mixed with as much sodium hydroxide solution until a degree of neutralization of 40 mol%, based on the one used  Acrylic acid. The partially neutralized gel will then analogous to the production of polymer A1 dried, ground, ge sieves and cross-links.

Polymer A6

The base polymer gel A is mixed with as much sodium hydroxide solution until a degree of neutralization of 40 mol%, based on the one used Acrylic acid. The partially neutralized gel will then dried on a drum dryer, ground in a pin mill and sieved at 100-800 µm. Post-networking takes place in one Lödige mixer, using 1 kg of polymer powder over a two-component sprayed a crosslinker solution of the following composition: 4% by weight of methanol, 6% by weight of water, 0.2% by weight of 2-oxazolidinone, based on polymer powder used. Then that will moist product at 180 ° C for 90 minutes in a forced-air drying cabinet annealed. The dried product is sieved at 850 m to To remove lumps.

Polymer A7

The base polymer gel A is neutralized analogously to polymer A6, dried and ground. Then the powder is in one Waring laboratory mixer sprayed with crosslinker solution. The solution is composed so that the following dosage based on a set base polymer is reached: 0.30 wt .-% 2-oxo-tetrahy dro-1,3-oxazin, 3% by weight 1,2-propanediol, 7% by weight water, and 0.2% by weight boric acid. The moist polymer is then at 175 ° C for 60 min. dried.

Polymer A8

1040 g of pure acrylic acid are placed in a 5 l polymerization flask diluted with 2827 g of deionized water. Adds to this solution 5.2 g of allyl methacrylate are added with stirring, and the mixture is rendered inert the sealed flask by passing nitrogen through it. The Polymerization is then accomplished by adding 0.52 g of 2-2'-azobisami dinopropane dihydrochloride, dissolved in 25 ml deionized water, 165 mg hydrogen peroxide 35% by weight, dissolved in 12 g completely salted water and 20.8 mg ascorbic acid, dissolved in 15 ml full desalinated water started. Approx. 3 hours after finishing the Reaction, the gel is crushed mechanically and at 50 ° C below Vacuum dried in a drying cabinet, in a coffee grinder ground, and finally sieved at 150-800 microns.

The polymer obtained in this way is mixed in a Waring laboratory mixer Sprayed crosslinker solution of the following composition: 2.5% by weight 1,2-propanediol, 2.5% by weight water, 0.2% by weight ethylene glycol digly cidyl ether, based on the polymer used. Then will the moist product at 120 ° C for 120 minutes in a circulating air dryer  cabinet annealed. The dried product is abge at 850 microns sieves to remove lumps.

Production of post-crosslinked polymer II Polymer B1

In 2123 g 5.5% by weight salt-free polyvinylamine solution (K- Value 137) was 4.1 g of ethylene glycol diglycidyl ether at room temperature rature stirred homogeneously, the solution at 60 ° C overnight pert. The resulting gel was crushed mechanically, at 80 ° C dried in vacuo, ground and sieved at 150-800 µm. This Polymer is mixed in a Waring laboratory mixer with a cross-linking solution sprayed. The solution is composed so that the following Dosage based on the base polymer used is achieved: 0.20% by weight ethylene glycol diglycidyl ether, 2.5% by weight 1,2-propane diol and 2.5 wt% water. The moist polymer then becomes 120 ° C for 60 min. dried.

Base polymer B

621 g of a commercially available polyethyleneimine (POLYMIN® P, Visko Brookfield at 20 ° C, approx. 22000 m Pas) with 279 g least Mix the water into a homogeneous solution. At room temperature 6.0 g of ethylene glycol diglycidyl ether, dissolved in 100 g least Water, stirred in and homogenized. The mixture turns on finally annealed for 6 hours at 80 ° C in the covered form. The resulting gel is then mechanically crushed Dried 80 ° C in vacuo, ground and sieved at 150-850 microns.

Polymer B2

The base polymer B is crosslinked in a Waring laboratory mixer sprayed zer solution of the following composition: 2.5% by weight 1,2-propanediol, 2.5% by weight water, 0.2% by weight ethylene glycol digly cidyl ether, based on the polymer used. Then will dry the moist product at 120 ° C for 120 minutes in a vacuum cabinet annealed. The dried product is abge at 850 microns sieves to remove lumps.

Polymer B3

The base polymer B is crosslinked in a Waring laboratory mixer sprayed zer solution. The solution is so composed that reached the following dosage based on the base polymer used is: 0.20% by weight ethylene glycol diglycidyl ether, 2.5% by weight 1,2-propanediol and 2.5% by weight water. The wet polymer will then at 120 ° C for 60 min. dried.  

Polymer B4

The base polymer B is crosslinked in a Waring laboratory mixer sprayed zer solution. The solution is so composed that reached the following dosage based on the base polymer used is: 0.20 wt .-% glutardialdehyde, 3.0 wt .-% 1,2-propanediol and 2.0 wt% water. The moist polymer is then at 120 ° C for 60 min. dried.

Polymer B5

The base polymer B is crosslinked in a Waring laboratory mixer sprayed zer solution. The solution is so composed that reached the following dosage based on the base polymer used is: 0.2 wt .-% 2-oxazolidinone, 3.0 wt .-% 1,2-propanediol and 2.0 wt% water. The moist polymer is then at 180 ° C for 60 min. dried and screened at 850 µm.

The polymers made according to the above examples were single tested, the results are in Table 1 below summarized:

Table 1

Examples 8.1 to 8.16

Polymers A and B that were post-crosslinked became homogeneous Mixtures created. The polymers used, their Mi  conditions and the application-technical measurement results the mixtures are shown in Table 2.

Post-crosslinking of mixtures of base polymer powders of polymers I and II Example 9.1-9.3

Polymer powder produced according to Examples A0 to A8, however Without surface post-crosslinking, polymer powder was used represents according to the example B and B1 (without upper described there surface post-crosslinking) homogeneously mixed and in a Waring-La Bormischer with crosslinking solution (2.5 wt .-% 1,2-propanediol, 0.2 % By weight of ethylene glycol diglycidyl ether and 2.5% by weight of water) speaks and then dried at 120 ° C for 60 minutes. Used Polymer types, mixing ratios and test results are in Table 3 summarized below.  

Example 10

100 g of a graft copolymer based on polyethylene glycol average molecular weight 9000 (70 g) and N-vinylformamide (30 g) with a K value of. . . . was diluted with 900 g of demineralized water, with 20 g of a 40 wt .-% sodium bisulfite solution and 67 g of one 25 wt .-% aqueous sodium hydroxide solution stirred at 80 ° C. In the course Over a period of 24 hours, a further 20.1 g of 25% strength by weight NaOH solution solution admitted. The degree of hydrolysis was 81.4% of theory at pH 3.5 with polyelectrolyte titration. This polymer solution was using ultrafiltration on a membrane (exclusion limit 1000 D) desalinated.

200 g of a polymer solution desalinated in this way (non-volatile content 5%) were mixed with 0.2 g of acrylic acid and crosslinked in a vacuum oven at 175 ° C. in a teflon-coated tub for 10 minutes. The polymer thus obtained was dry and could easily be ground. A 1: 1 powder mixture of this polymer and a crosslinked polyacrylic acid (base polymer A0) was examined for its application properties.
Intake capacity (30 min) [g / g]: 32.7
Absorption capacity (4 h) [g / g]: 46.3
Retention (30 min) [g / g]: 19.2
AAP (0.7 psi) [g / g]: 17.0

Example 11

50 g of a high molecular weight polyethyleneimine (molecular weight 500000) with a solids content of 49.5 wt .-% with 100 parts a copolymer of acrylamide (98 g) and hydroxyethyl acrylate (2nd g) K value 72.1 and a solids content of 14.8% by weight and in a laboratory kneader from Jahnke & Kunkel for 1 hour kneaded. The gel was dried in vacuo at 70 ° C. for 24 h and turned on finally ground.

A 1: 1 powder mixture of this polymer and a crosslinked polyacrylic acid (according to Example 1a) was examined for its absorbent properties.
Absorption capacity (30 min) [g / g]: 26.5
Retention (30 min) [g / g]: 10.4
AAP (0.3 psi) [g / g]: 17.6

Example 12

600 g of a fully desalinated polyvinylamine homopolymer with a K value of 91, a degree of hydrolysis of 90.1% and a solids content of 4% by weight were mixed with 1 g of acrylic acid in a laboratory kneader and crosslinked at a temperature of 100.degree . During this time, a further 600 g of the polyvinylamine were added and a total of 490 g of water were distilled off. After a period of 5 hours the polymer was insoluble in water. The gel was then dried at 75 ° C. in vacuo for 24 h and then ground. A 1: 1 powder mixture of this polymer and a crosslinked polyacrylic acid (base polymer A0) was tested.
Intake capacity (30 min) [g / g]: 30.3
Retention (30 min) [g / g]: 15.1
Retention (4 h) [g / g]: 23.3
Absorption capacity (4 h) [g / g]: 42.0
AAP (0.7 psi) [g / g]: 16.2
AAP (0.7 psi Jayco) [g / g]: 15.3
AAP (0.7 psi Jayco, 4 h) [g / g]: 22.3

Example 13

500 g of a fully desalinated polyvinylamine homopolymer with a K value of 85, a degree of hydrolysis of 92.1% and a solids content of 6.7% by weight were mixed in a laboratory kneader with 1 g of methyl acrylate and at a temperature of 100 ° C networked. During this time, a further 500 g of the polyvinylamine were added and a total of 360 g of water were distilled off. After a period of 5 hours the polymer was insoluble in water. The gel was then dried at 75 ° C. in vacuo for 24 h and then ground. A 1: 1 powder mixture of this polymer and a crosslinked polyacrylic acid (base polymer A0) was tested as a super absorber.
Absorption capacity (30 min) [g / g]: 28.7
Retention (30 min) [g / g]: 17.9
AAP (0.3 psi) [g / g]: 15.3

Example 14

200 g of a fully desalinated polyvinylamine homopolymer solution (not liquid content 5%) were mixed with 0.4 g of urea and 175 ° C in a Teflon-coated tub for 10 minutes in Networked vacuum drying cabinet. The polymer thus obtained was after a further drying step at 185 ° C brittle and dry and could be ground easily.

A 1: 1 powder mixture of this polymer and a crosslinked polyacrylic acid from Example 1a) was tested.
Absorption capacity (30 min) [g / g]: 24.9
Retention (30 min) [g / g]: 10.1
Absorption capacity (4 h) [g / g]: 41.9
Retention (4 h) [g / g]: 16.5
AAP (0.7 psi 1 h) [g / g]: 15.6

Example 15

200 g of a fully desalinated polyvinylamine homopolymer solution (not volatile content 5%) were mixed with 0.4 g propylene carbonate and at 175 ° C in a Teflon coated tub for 10 minutes networked in the vacuum drying cabinet. The polymer thus obtained was brittle after a further drying step at 185 ° C. dry and could be easily ground.

A 1: 1 powder mixture of this polymer and a crosslinked polyacrylic acid from Example 1a) was tested as a superabsorbent.
Absorption capacity (30 min) [g / g]: 25.0
Retention (30 min) [g / g]: 10.6
Absorption capacity (4 h) [g / g]: 40.6
Retention (4 h) [g / g]: 16.8
AAP (0.7 psi 1 h) [g / g]: 16.4

Claims (17)

1. Containing hydrogel-forming polymer mixture

• a) a hydrogel-forming polymer I with acid residues and
• b) a hydrogel-forming polymer II with amino and / or imino residues,

wherein the ratio of the acid residues to the sum of amino / imino residues is 1: 9 to 9: 1. 2. Hydrogel-forming polymer mixture according to claim 1, characterized characterized in that the hydrogel-forming polymer I crosslinked Is polyacrylic acid, the carboxylic acid groups of 0 to 50% be present as an alkali or ammonium salt. 3. hydrogel-forming polymer mixture according to claim 1 or 2, characterized in that the hydrogel-forming polymer II is cross-linked and a polyethyleneimine, one with ethyleneimine is grafted polyamidoamine and / or grafted polyamine. 4. hydrogel-forming polymer mixture according to claim 1 or 2, characterized in that the hydrogel-forming polymer II is a cross-linked polyvinylamine. 5. Hydrogel-forming polymer mixture according to claims 1 or 2, characterized in that the hydrogel-forming polymer II by copolymerization of vinylformamide and one or several monoethylenically unsaturated compounds, thereon following hydrolysis and optionally desalination and on closing networking was obtained. 6. hydrogel-forming polymer mixture according to claim 1 or 2, because characterized in that the hydrogel-forming polymer II a graft copolymer of vinyl formamide on polymeric compound is then hydrolyzed, if necessary desalinated and cross-linked.   7. hydrogel-forming polymer mixture according to claims 1, 2 and 5, characterized in that the hydrogel-forming Po lymer II is a copolymer of vinyl formamide and monoethylene is unsaturated mono- and / or polycarboxylic acids finally hydrolyzed, optionally desalted and Heating was networked. 8. hydrogel-forming polymer mixture according to claims 1, 2 and 5, characterized in that the hydrogel-forming Po lymer II is a copolymer of vinyl formamide and monoethylene is unsaturated mono- and / or polycarboxylic acids, the hydro lysed, optionally desalted, crosslinked by heating was and then with a cationic polymer or Copolymer based on polyvinylamine or polyethyleneimine and / or with at least one bifunctional crosslinker be networked. 9. hydrogel-forming polymer mixture according to claims 1 to 3, characterized in that polymer II is a polyethylenei min. a polyamidoamine grafted with ethyleneimine or a Polyamine is that by reaction with α, β-unsaturated car bonic acids, their esters or by Strecker reaction polyme was modified analogously and then thermally crosslinked has been. 10. Hydrogel-forming polymer mixture according to claim 1 with a SFC index of ≧ 10000. 11. Hydrogel-forming polymer mixture according to claim 1 with a PAI index (NaCl) of ≧ 100 after a swelling time of 16 h. 12. Hydrogel-forming polymer mixture according to claim 1 with a PAI index (Jayco) of ≧ 150 after a swelling time of 16 h. 13. Hydrogel-forming polymer mixture according to claim 1 with a Diffusing absorbency under pressure of ≧ 30 g / g. 14. Hydrogel-forming polymer mixture according to claim 1 with a Wicking Distance ≧ 5 g in the Wickings Performance Test. 15. Hydrogel-forming polymer mixture according to claim 1 with a Acquisition Time 3 of ≦ 9 g in the Acquisition Time / Rewet test vacuum.   16. The hydrogel-forming polymer mixture according to claim 1, which by Mixing polymer gel I and polymer powder II or Polymer powder I and polymer gel II is obtained. 17. The hydrogel-forming polymer mixture according to claim 1, which by Add a mixture component I or II as a powder in the Reaction mixture of the other component is obtained.