EP3207178A1

EP3207178A1 - Solidifying composition for paper and cardboard

Info

Publication number: EP3207178A1
Application number: EP15750736.9A
Authority: EP
Inventors: Hans-Joachim Haehnle; Christoph Hamers; Anton Esser; Stefan Spange; Katja TROMMLER; Hendryk WUERFEL; Susan SEIFERT; Tina WALTHER
Original assignee: BASF SE
Current assignee: BASF SE
Priority date: 2014-10-13
Filing date: 2015-08-14
Publication date: 2017-08-23
Also published as: WO2016058730A1; CN107002366A; CA2964420A1; BR112017007524A2; US20170233950A1; KR20170068561A; MX2017004893A

Abstract

The invention relates to an aqueous composition containing (a) polymers having primary amino groups and/or amidine groups with a total content of said groups of ≥1.5 meq/g polymer and (b) 0.01 - 50 mol-% 1,4-cyclohexandion (b) based on the total amount of primary amino groups and amidine groups of the polymers. The aqueous composition has a pH-value ≤6. The invention also relates to the use thereof as a solidifying agent and to a method for producing paper and cardboard, to the use of the aqueous composition and to the thus produced paper and cardboard.

Description

Solidification composition for paper and board

Description The invention relates to an aqueous composition containing

(A) polymers having primary amino groups and / or amidine groups with a total content of these groups of> 1, 5 meq / g polymer and (b) 0.01 to 50 mol% of 1, 4-cyclohexanedione (b) based on the total amount of primary

Amino groups and / or amidine groups of the polymers, wherein the aqueous composition has a pH <6. The present invention further relates to its use as a solidifier. Furthermore, the application relates to a process for the production of paper and board, use of the aqueous composition and hereafter produced paper and cardboard.

Today's papermaking processes are geared towards reducing resources or making better use of resources. In particular, developments are taking place to use shorter fiber lengths, to reduce the basis weights and to use a higher proportion of filler. All these innovations in turn have a negative impact on the strength, especially the dry strength of paper, so that especially in this direction new solidifiers are sought. Suitable solidifying agents include polyvinylamine, polyethyleneimine and polyacrylamides.

WO 2008/022905 teaches a process for the treatment of cellulose-containing fibers or fabrics containing them with a combination of polyvinylamines and polyether acetylacetates.

EP 2059539 describes the modification of the polyacrylamide with glyoxal, which lead to solidification in the papermaking process in that the aldehyde groups bound by the polymer react with the hydroxy groups of the cellulose, which ultimately causes crosslinking. However, glyoxilated polyacrylamides have a low storage stability, which can only be counteracted by a high dilution.

WO 03/066716 teaches the production of foams from water-absorbing basic polymers of polyvinylamine and a crosslinker. As a crosslinker, 1,4-cyclohexanedione is mentioned among others. According to the examples, an aqueous mixture containing Polyvi- nylamin, ethylene diglycidyl ether as a crosslinking agent and a surfactant is first foamed and then poured the foamed mixture on a flat surface and dried at 70 ° C. The basic foams thus obtained are used as hydrogels in hygiene articles such as diapers Accordingly, the above-mentioned aqueous composition, its use as a solidifier, especially for processes for producing paper and board have been found. Further, a process for producing paper and board using the aqueous composition of the present invention and the paper and paperboard prepared hereafter were found.

It has been found that the aqueous composition according to the invention, when added to the papermaking process, leads to solidification of the paper. An explanation of how the fibers solidify is that the composition results in a crosslinking reaction of the primary amino groups and optionally present amidine groups of the polymers with the 1,4-cyclohexanedione. Such a crosslinking reaction would be a pH-dependent equilibrium which, when added to the pulp, which generally has a pH in the range of 7 to 8, is shifted towards the crosslinked structure. As the paper dries, the balance would shift to the right side. The equilibrium of the aqueous composition is shifted to the side of the starting materials in the acid, so that the composition is particularly stable in acidic form.

The total content of primary amino groups and / or amidine groups is to be understood as the sum of the molar fractions of these groups given in milliequivalent per gram of polymer (solid).

If in the context of this application a "polymer having primary amino groups and / or amidine groups (solid)" is mentioned, this is understood to mean the amount of polymer without counterions, taking into account potentially charge-carrying structural units in the charged form, ie, for example, amino groups in the protonated form and acid groups in the deprotonated form, counterions of the charged structural units such as Na, chloride, phosphate, formate, acetate, etc. are not taken into account The determination of the underlying molecular weight of the polymer without counterion is described below in the examples primary amino groups and / or amidine groups having a total content of these groups of> 1, 5 meq / g polymer and 0.01 to 50 mol% of 1, 4-cyclohexanedione (b) based on the total amount of primary amino groups and amidine groups of the polymers (solid and 50% by weight of water based on the aqueous composition Particular preference is given to aqueous compositions containing from 60 to 98% by weight, in particular from 70 to 95% by weight, of water, based on the aqueous composition.

The composition according to the invention has a pH <6. It therefore has an acidic pH. Preferably, the compositions have a pH in the range of 2 to 6.

The determination of the pH is carried out on a sample of the aqueous composition at 25 ° C and atmospheric pressure by means of a pH electrode. Polymer with primary amino groups and / or amidine groups

The polymers having primary amino groups and / or amidine groups are polymers having primary amino groups and optionally amidine groups. They usually have average molecular weights M _w (determined by means of static light scattering) in the range from 10,000 to 10,000,000 daltons, preferably in the range from 20,000 to 5,000,000 daltons, particularly preferably in the range from 40,000 to 3,000,000 daltons. Very particularly preferred is an upper limit of the average molecular weight of 2,000,000 Dalton.

The average molecular weight M _w is understood here and below as the weight-average molecular weight.

Polymers having primary amino groups and / or amidine groups are known, cf. the DE 35 06 832 A1 and DE 10 2004 056 551 A1 referred to in the prior art. The following is both of homopolymers, so polymers of a monomer as well as copolymers mentioned. The term "copolymers" encompasses polymers of two monomers as well as of more than two monomers, for example terpolymers.

In the following, when referring to a copolymer obtainable by "polymerizing" followed by a list of monomers, it is to be understood that the monomer composition comprises these monomers as the main constituent Preferably, the monomer composition is at least 95% by weight , in particular to 100 wt .-%, of these monomers.

Preferably, the polymers are selected with primary amino groups and / or amidine groups of the group of polymer classes consisting of:

(A) Hydrolyzed homopolymers of N-vinylcarboxamide

(B) Hydrolyzed copolymers of N-vinylcarboxamide and other neutral monoethylenically unsaturated monomers

(C) Hydrolyzed copolymers of N-vinylcarboxamide and anionic monoethylenically unsaturated monomers

(D) Hydrolyzed copolymers of N-vinylcarboxamide and cationic monoethylenically unsaturated monomers

(E) Hydrolyzed homopolymers of N-vinylcarboxamide reacted polymer-analogously

(F) Hofmann degradation of homopolymers or copolymers of (meth) acrylamide

(G) polymers containing ethyleneimine units

(A) Partially and fully hydrolyzed homopolymers of N-vinylcarboxamide are obtainable by polymerizing at least one N-vinylcarboxamide of the formula H

CH ₂ = CH-IM (I),

xCO-R

in which R ¹ signifies H or C 1 to C 6 alkyl, preferably R ¹ signifies H, and if appropriate compounds (iii) which have at least two ethylenically unsaturated double bonds in the molecule, and subsequent partial or complete hydrolysis of the copolymerized into the polymer. th units of the monomers (I) to form amino groups.

The hydrolysis of the carboxylic acid amide radicals of the copolymerized units of the monomers (I) converts the group -NH-CO-R ¹ into the group -IMH 2. Hydrolyzed homopolymers of N-vinylcarboxamide are commonly referred to as polyvinylamines, which are characterized by their degree of hydrolysis.

Preference is given to partially and completely hydrolyzed homopolymers having a degree of hydrolysis

10 mol%, preferably> 20 mol%, in particular ^ 30 mol%. Their degree of hydrolysis is equivalent to the molar calculated total percentage of the primary amino groups and / or amidine groups of the polymers based on the N-vinylcarboxäureamideinheiten originally present. The degree of hydrolysis can be determined by analysis of the formic acid released in the hydrolysis. For example, the latter can be achieved enzymatically with the help of a test kit from Boehminger Mannheim. The total content of primary amino groups and / or amidine groups of the partially / fully hydrolyzed vinylformamide homopolymers is determined in a manner known per se from the degree of hydrolysis determined by means of analysis and the ratio of amidine / primary determined by ¹³ C-NMR spectroscopy. Calculated amino group.

In the case of copolymers or polymer-analogously reacted polymers, the molar composition of the structural units of the polymer present at the end of the reaction is determined on the basis of the amounts of monomers used, the particular degree of hydrolysis, the ratio of amidine to prim amino groups and optionally the proportion which has been reacted polymer-analogously , With the aid of the molar mass of the individual structural units, the molar fraction of primary amino groups and / or amidine units in meq, which is in 1 g of polymer, can be calculated therefrom. Amidine groups can form as is well known in partially hydrolyzed homo- and copolymers of vinylformamide. In the case of adjacent amino and formamide groups, ring closure and hence amidine formation can occur. This results in a six-membered ring with amide structure.

Since the amidine unit is in dynamic equilibrium with adjacent vinylamine and vinylformamide units and is also reactive with the 1,4-cyclohexanedione, they also contribute to the effectiveness in the inventive composition. The determination of the degree of hydrolysis recorded in the same way the formation of primary amino groups as well as amidine units, since in both cases exactly one molecule of formic acid is released.

(B) Hydrolyzed copolymers of N-vinylcarboxamide and other neutral ethylenically unsaturated monomers are obtainable by polymerizing

(i) at least one monomer of the formula

H

CH ₂ = CH-N (I),

CO in the R ¹ = H or C ¹ to C 6 alkyl,

(iia) at least one further neutral monoethylenically unsaturated monomer and (iii) optionally compounds which have at least two ethylenically unsaturated double bonds in the molecule and subsequent partial or complete hydrolysis of the units of the monomers (I) copolymerized into the polymer to form amino groups.

As the polymers (B), the reaction products obtained by copolymerizing

(i) N-vinylformamide and

(ii) acrylonitrile and / or vinyl acetate and subsequent removal of formyl groups from the copolymerized in the copolymer vinylformamide units to form amino groups are available.

In the case of copolymers with vinyl acetate, the ester group is usually hydrolyzed to the alcohol under the hydrolysis conditions to form vinyl alcohol units. This also applies to the copolymers (C) and (D) described below.

(C) Hydrolyzed copolymers of N-vinylcarboxamide and anionic monoethylenically unsaturated monomers are available by polymerization

(i) at least one monomer of the formula

H

CH ₂ = CH-N ^/ (I),

xCO-R in which R ^{1 is} H or C ^{1 to} C 6 alkyl,

(Uv) one or more monomers selected from monoethylenically unsaturated sulfonic acids, monoethylenically unsaturated phosphonic acids, monounsaturated esters of phosphoric acid, monoethylenically unsaturated carboxylic acids having 3 to 8 C atoms in the molecule and / or their alkali metal, alkaline earth metal or ammonium salts, and

(ii, a) optionally one or more further neutral monoethylenically unsaturated monomers, (iii) optionally compounds which have at least two ethylenically unsaturated double bonds in the molecule and subsequent partial or complete hydrolysis of the units of the monomers (I) copolymerized into the polymer Formation of amino groups.

Preference is given to amphoteric polymers having primary amino groups and / or amidine groups (C) by copolymerizing

(i) N-vinylformamide,

(ii, b) acrylic acid, methacrylic acid and / or their alkali metal, alkaline earth metal or ammonium salts and optionally

(ii, a) acrylonitrile and / or methacrylonitrile and subsequent partial or complete elimination of formyl groups from the copolymerized in the polymer N-vinylformamide to form amino groups are available. (D) Hydrolyzed copolymers of N-vinylcarboxamide and cationic monoethylenically unsaturated monomers are obtainable by polymerization of at least one monomer of the formula

H

CH ₂ = CH-N ^/

in which R ^{1 is} H or C ¹ to C 6 alkyl,

(iic) optionally one or more monomers selected from quaternized monoethylenically unsaturated monomers or protonatable secondary or tertiary amino groups-carrying monoethylenically unsaturated monomers

(iia) optionally one or more further neutral monoethylenically unsaturated monomers

(iii) optionally compounds which have at least two ethylenically unsaturated double bonds in the molecule and subsequent partial or complete hydrolysis of the units of the monomers I copolymerized into the polymer to form amino groups.

Examples of monomers of the formula I are N-vinylformamide, N-vinylacetamide, N-vinylpropionamide and N-vinylbutyramide. The monomers of group (i) may be used alone or in admixture in the copolymerization with the monomers of the other groups. The preferred monomer of this group is N-vinylformamide.

If N-vinylcarboxamides (i) are copolymerized together with (ii) at least one other monoethylenically unsaturated monomer and the copolymers then hydrolyzed to form amino groups, the copolymers (B), (C) and (D) are obtained.

By "further" monomers (iia) "are meant monomers which do not fall under the monomers of the formula I. Furthermore, they are neutral (uncharged), so carry neither cationic nor anionic radicals, and thus are different from the monomers of the groups (üb) and (iic). Examples of neutral monomers of the group (iia) are monoesters of α, β-ethylenically unsaturated mono- and dicarboxylic acids with C 1 -C 30 -alkanols, C 2 -C 3 -alkanediols, amides of α, β-ethylenically unsaturated monocarboxylic acids and their N-alkyl- and Ν, Ν-dialkyl derivatives, nitriles of α, β-ethylenically unsaturated mono- and dicarboxylic acids, esters of vinyl alcohol and allyl alcohol with C 1 -C 8 -monocarboxylic acids, N-vinyllactams, non-nitrogen-containing heterocycles having α, β-ethylenically unsaturated double bonds, Vinyl aromatics, vinyl halides, vinylidene halides, C 2 -C 8 monoolefins and mixtures thereof. Suitable representatives are, for example, methyl (meth) acrylate (this notation symbolizes both "acrylates" and "methacrylates" here as well as in the text below), methyl methacrylate,

Ethyl (meth) acrylate, ethyl methacrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, tert-butyl ethacrylate, n-ocytl (meth) acrylate, 1, 1 , 3,3-tetramethylbutyl (meth) acrylate, ethylhexyl (meth) acrylate and mixtures thereof.

Further suitable monomers of group (iia) are 2-hydroxyethyl (meth) acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate and mixtures thereof.

Further suitable monomers of group (iia) are acrylamide, methacrylamide, N-methyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N-isopropyl (meth) acrylamide, N-ethyl (meth ) acrylamide, n-propyl (meth) acrylamide, N- (n-butyl) (meth) acrylamide, tert-butyl (meth) acrylamide, n-octyl (meth) acrylamide, 1, 1, 3,3- Tetramethylbutyl (meth) acrylamide, ethylhexyl (meth) acrylamide and mixtures thereof.

Further examples of monomers of group (iia) are nitriles of α, β-ethylenically unsaturated mono- and dicarboxylic acids such as, for example, acrylonitrile and methacrylonitrile. The presence of units of these monomers in the copolymer during or after the hydrolysis leads to products which may have an additional type of amidine units, cf. e.g.

EP-A 0 528 409 or DE-A 43 28 975. In the hydrolysis of N-vinylcarboxamide polymers, 5-ring amidine units are formed in a secondary reaction by reacting vinylamine units with an adjacent nitrile group in the polymer.

These 5-ring amidines also contribute to the reactivity with the 1,4-cyclohexanedione. Since exactly one molecule of formic acid also forms in the formation of a 5-ring amidam, these are also included in the determination of the degree of hydrolysis and thus also in the calculation of the total proportion of primary amino groups and / or amidine groups. Suitable monomers of the group (iia) are furthermore N-vinyllactams and derivatives thereof, which, for. B. one or more Ci-C6-alkyl substituents (as defined above) may have. These include N-vinylpyrrolidone, N-vinylpiperidone, N-vinylcaprolactam, N-vinyl-5-methyl-2-pyrrolidone, N-vinyl-5-ethyl-2-pyrrolidone, N-vinyl-6-methyl-2-piperidone, N-vinyl-6-ethyl-2-piperidone, N-vinyl-7-methyl-2-caprolactam, N-vinyl-7-ethyl-2-caprolactam and mixtures thereof.

Further suitable monomers of group (iia) are ethylene, propylene, isobutylene, butadiene, styrene, α-methylstyrene, vinyl formate, vinyl acetate, vinyl propionate, vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride and mixtures thereof.

Particularly preferred monomers of group (iia) are acrylonitrile and vinyl acetate.

The aforementioned monomers (iia) can be used individually or in the form of any desired mixtures. Typically, they are used in amounts of 1 to 90 mol%, preferably 10 to 80 mol% and particularly preferably 10 to 60 mol%, based on the total monomer composition.

For the preparation of polymers having primary amino groups and / or amidine groups, suitable monoethylenically unsaturated monomers of group (ii) are also anionic monomers, which are referred to above as monomers (Ub). They may optionally be copolymerized with the neutral monomers (iia) and / or cationic monomers (iic) described above.

Anionic monomers are formed from monomers containing acidic groups by cleavage of protons. Examples of anionic monomers of the group (c) are ethylenically unsaturated C3 to Cs carboxylic acids such as acrylic acid, methacrylic acid, dimethacrylic acid, ethacrylic acid, maleic acid, fumaric acid, itaconic acid, mesaconic acid, citraconic acid, methyl enmalonic acid, allylacetic acid, vinylacetic acid and crotonic acid. Also suitable as monomers of this group are monomers containing sulfo groups, such as vinylsulfonic acid, acrylamido-2-methylpropanesulfonic acid, allyl- and methallylsulfonic acid and styrenesulfonic acid, phosphono-containing monomers, such as vinylphosphonic acid and monoalkylphosphate groups. The monomers of this group can be used alone or in admixture with each other, in partially or completely neutralized form in the copolymerization. For neutralization, for example, alkali metal or alkaline earth metal bases, ammonia, amines and / or alkanolamines are used. Examples of these are sodium hydroxide solution, potassium hydroxide solution, soda, potash, sodium bicarbonate, magnesium oxide, calcium hydroxide, calcium oxide, triethanolamine, ethanolamine, morpholine, diethylenetriamine or tetraethylenepentamine.

Acrylic acid, methacrylic acid, vinylsulfonic acid, vinylphosphonic acid, and acrylamido-2-methylpropanesulfonic acid are particularly preferred as monomers of group (g).

Cationic monomers contain basic groups and are cationizable either by quaternization cationic or by addition of protons. Suitable cationic monomers (iic) which are copolymerizable are the esters of α, β-ethylenically unsaturated mono- and dicarboxylic acids with aminoalcohols, preferably C2-C12-aminoalcohols. These may be C 1 -C 12 monoalkylated or dialkylated on the amine nitrogen. As the acid component of these esters are z. For example, acrylic acid, methacrylic acid, fumaric acid, maleic acid, itaconic acid, crotonic acid, maleic anhydride, monobutyl maleate and mixtures thereof. Preference is given to using acrylic acid, methacrylic acid and mixtures thereof.

Preferred monomers are dialkylaminoethyl (meth) acrylates, dialkylaminopropyl (meth) acrylates, dialkylaminoethyl (meth) acrylamides, dialkylaminopropyl (meth) acrylamides, diallyldimethylammonium chloride, vinylimidazole, alkylvinylimidazoles and the cationic monomers each neutralized and / or quaternized with mineral acids.

Specific examples of the esters of α, β-ethylenically unsaturated mono- and dicarboxylic acids with amino alcohols are N-methylaminomethyl (meth) acrylate, N-methylaminoethyl (meth) acrylate, N, N-dimethylaminomethyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate,, N, N-diethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylate, N, N-diethylaminopropyl meth) acrylate, N, N-dimethylaminocyclohexyl (meth) acrylate. Dialkylated amides of α, β-ethylenically unsaturated monocarboxylic and dicarboxylic acids with diamines are, for example, dialkylaminoethyl (meth) acrylamides, dialkylaminopropyl (meth) acrylamides, N- [2- (dimethylamino) ethyl] acrylamide, N- [2- (2- Dimethylamino) ethyl] methacrylamide, N- [3- (dimethylamino) propyl] acrylamide, N- [3- (dimethylamino) propyl] methacrylamide, N- [4- (dimethylamino) butyl] acrylamide, N- [4- (2- Dimethylamino) butyl] methacrylamide, N- [2- (diethylamino) ethyl] acrylamide, N- [2- (diethylamino) ethyl] methacrylamide.

Examples which may be mentioned of methylvinylimidazoles are 1-vinyl-2-methylimidazole, 3-vinylimidazole N-oxide, 2- and 4-vinylpyridine N-oxides and also betaine derivatives of these monomers. Particularly preferred monomers of group (iic) are diallyldimethylammonium chloride (DADMAC).

The cationic monomers may be completely or even partially neutralized or quaternized, e.g. each to 1 to 99%. Preferably used quaternizing agent for the cationic monomers is methyl chloride. However, the quaternization of the monomers can also be carried out with dimethyl sulfate, diethyl sulfate or with other alkyl halides such as ethyl chloride or benzyl chloride.

A further modification of the copolymers is possible by using in the copolymerization monomers of group (iii) which contain at least two double bonds in the molecule, eg. As triallylamine, methylenebisacrylamide, glycol diacrylate, glycol dimethacrylate, glycerol intracrylate, pentaerythritol triallyl ether, Ν, Ν-Divinylethylenharnstoff, tetraallylammonium chloride, at least two times with acrylic acid and / or methacrylic esterified polyalkylene glycols or polyols such as pentaerythritol, sorbitol and glucose. Monomers of group (iii) act as crosslinkers. Therefore, the monomer DADMAC is not counted to this group but to the cationic monomers. If at least one monomer of the above group is used in the polymerization, the amounts used are up to 2 mol%, e.g. B. 0.001 to 1 mol%.

Furthermore, it may be useful for modifying the polymers to combine the use of vorste-increasing crosslinker with the addition of regulators are typically used 0.001 to 5 mol% based on the total monomer composition. All the literature known regulators can be used, eg. As sulfur compounds such as mercaptoethanol, 2-ethylhexyl thioglycolate, thi-oglycolic acid and dodecyl mercaptan and sodium hypophosphite, formic acid or Tribromchlormethan.

The preparation of the above-described polymers having primary amino groups and / or amine groups of the classes (A), (B), (C) and (D) can be carried out by solution, precipitation, suspension or emulsion polymerization. Preference is given to solution polymerization in aqueous media. Suitable aqueous media are water and mixtures of water and at least one water-miscible solvent, e.g. Example, an alcohol such as methanol, ethanol, n-propanol or isopropanol.

The hydrolysis of the copolymers can be carried out in the presence of acids or bases or else enzymatically. In the case of hydrolysis with acids, the amino groups formed from the vinylcarboxylic acid amide units are present in salt form. The hydrolysis of vinylcarboxylic acid amide copolymers is described in detail in EP-A 0 438 744, page 8, line 20 to page 10, line 3. The remarks made there apply correspondingly to the preparation of the polymers to be used according to the invention having primary amino groups and / or amidine groups. The polymers having primary amino groups and / or amidine groups can also be used in the form of the free bases in the process according to the invention. Such polymers are useful, for example, in the hydrolysis of polymers containing vinylcarboxylic acid units with bases.

Preference is given to partially and fully hydrolyzed copolymers of the classes (B), (C) and (D) with a degree of hydrolysis of> 10 mol%, preferably> 20 mol%, in particular> 30 mol%. Preference is given to partially and completely hydrolyzed copolymers of the classes (B), (C) and (D) obtainable by polymerizing

30-99 mol% of at least one monomer of the formula

H

CH ₂ = CH-N ^/ (I),

xCO-R in which R ^{1 is} H or C ^{1 to} C 6 alkyl, 0-70 mol% of one or more further neutral monoethylenically unsaturated monomers (iia),

0 - 70 mol% of one or more monomers (UB) selected from monoethylenically unsaturated sulfonic acids, monoethylenically unsaturated phosphonic acids, monounsaturated esters of phosphoric acid, monoethylenically unsaturated carboxylic acids having 3 to 8 carbon atoms in the molecule and / or their alkali metal, alkaline earth metal or ammonium salts,

0 - 70 mol% of one or more monomers (iic) selected from quaternized monoethylenically unsaturated monomers and protonatable secondary or tertiary amino-carrying monoethylenically unsaturated monomers, each based on the total monomer composition and

optionally compounds which have at least two ethylenically unsaturated double bonds in the molecule, with the proviso that the sum of the proportions of the monomers (iia), (trans) and (iic) is in total 1 to 70 mol%, and subsequent partial or complete hydrolysis of the in the polymer copolymerized units of the monomers (I) to form amino groups. In particular, such copolymers are preferred with a degree of hydrolysis ^ 30 mol%.

Particularly preferred are partially and fully hydrolyzed copolymers of N-vinylcarboxylic acid amide with further neutral, anionic and / or cationic monoethylenically unsaturated monomers, this monomer being selected from acrylonitrile, vinyl acetate, sodium acrylate, DADMAC, [3- (dimethylamino) propyl] acrylamide, N- [3- (dimethylamino) propyl] methacrylamide and the available by reaction with methyl chloride quaternized compounds of dimethylamino) propyl] acrylamide or N- [3- (dimethylamino) propyl] methacrylamide of the last two compounds. In particular, those having a degree of hydrolysis are preferably 30 mol%. Very particular preference is given to partially or fully hydrolyzed copolymers of N-vinylcarboxamide with sodium acrylate, and a degree of hydrolysis of> 30 mol%.

E) Hydrolyzed homopolymers of N-vinylcarboxamide, which were reacted polymer-analogously

Furthermore, the polymer-analogously reacted polymers of polymers of class A), ie polymer-analogously reacted polyvinylamines, are suitable, provided that these reaction products have the total content of primary amino groups and / or amidine groups essential to the invention. Suitable polymer-analogous reactions are the reaction with Michael systems as described in WO2007 / 136756. Michael systems are compounds with an unsaturated double bond which are conjugated to an electron-withdrawing group. Suitable Michael systems fall under the general formula II

wherein R ² and R ³ independently of one another are H, alkyl, alkenyl, carbonyl, carboxyl or carboxamide and X ^{1 is} an electron-withdrawing group or an amino group. Examples thereof are known as Michael systems: acrylamide, N-alkylacrylamide, methacrylamide, Ν, Ν-dimethylacrylamide, N-alkylmethacrylamide, N- (2-methylpropanesulphonic acid acrylamide, N- (glycolic acid) acrylamide, N- [3- (propyl) trimethylammonium chloride] acrylamide, Acrylonitrile, methacrylonitrile, acrolein, methyl acrylate, alkyl acrylate, methyl methacrylate, alkyl methacrylate, aryl acrylate, aryl methacrylates, [2- (methacryloyloxy) ethyl] trimethylammonium chloride, N- [3- (dimethylamino) propyl] methacrylamide, N- Ethylacrylamide, 2-hydroxyethyl acrylate, 3-sulfopropyl acrylate,

2-hydroxyethyl methacrylate, glycidyl methacrylate, pentafluorophenyl acrylate, ethylene diacrylate, ethylene dimethacrylate, heptafluorobutyl-1-acrylate, poly (methyl methacrylate), acryloylmorpholine,

3- (acryloyloxy) -2-hydroxypropyl methacrylate, dialkyl maleate, dialkyl itaconate, dialkyl fumarate, 2-cyanoethyl acrylate, carboxyethyl acrylate, phenylthioethyl acrylate, 1-adamantyl methacrylate, dimethylaminoneopentyl acrylate, 2- (4-benzoyl-3-hydroxyphenoxy) ethyl acrylate and dimethylaminoethyl methacrylate.

Preferred as the Michael system acrylamide. The Michael systems are used in an amount of 1 to 75 mol% based on the primary amino groups and / or amidine groups. The reaction conditions for the reaction are described in WO2007 / 136756, the disclosure of which is expressly incorporated by reference.

E) Also preferred are polymer-analogous reactions of the primary amino groups and / or amidine groups of the polymers A). The reaction products preferably contain structural units selected from the group of polymer units (III), (IV), (V), (VI) and (VII)

(III), (V),

in which

X- is an anion, preferably, chloride, bromide or iodide;

Y is carbonyl or methylene or a single bond;

R _{4 is} hydrogen, linear or branched C 1 -C 22 -alkyl

R5 is linear or branched C 1 -C 6 -alkylene, or linear or branched C 1 -C 6 -alkenylene

R6 linear or branched Ci-Ci2-alkylene, which is optionally substituted with hydroxyl, preferably CH ₂ CH (OH) CH ₂ or -Ethylen

R7 is hydrogen, linear or branched C 1 -C 22 -alkyl, preferably methyl or ethyl

Rs is hydrogen, linear or branched C 1 -C 22 -alkyl, linear or branched C 1 -C 22 -alkoxy, amino, linear or branched C 1 -C 22 -alkylamino, linear or branched C 1 -C 22

Dialkylamino, preferably amino

R 9 is linear or branched C 1 -C 12 -alkylene, preferably ethylene;

R 10 is hydrogen, linear or branched C 1 -C 22 -alkyl, preferably methyl or ethyl

The reaction conditions for the reaction are described in WO2009 / 017781, the disclosure of which is expressly incorporated by reference.

Reaction products containing units of the formula III are obtainable by polymer-analogous reaction of the primary amino groups and / or amidine groups of the polyvinylamines (polymers A) with alkylating agents. The alkylation can furthermore be carried out with alkyl glycidyl ethers, glycidol (2,3-epoxy-1-propanol) or chloropropanediol. Preferred alkyl glycidyl ethers are butyl glycidyl ether, 2-ethylhexyl glycidyl ether, hexadecyl glycidyl ether and C12 / C14 glycidyl ether. The reaction with alkyl glycidyl ethers is generally carried out in water, but can also be carried out in aqueous / organic solvent mixtures.

Reaction products containing units of the formula IV and VI are obtainable by polymer-analogous reaction of the primary amino groups and / or amidine groups of the polyvinylamines (polymers A) with alkylating agents or acylating agents.

Such acylating agents are selected from succinic anhydride, substituted succinic anhydrides which are substituted by linear or crosslinked C 1 -C 18 -alkyl or linear or crosslinked C 1 -C 18 -alkenyl, maleic anhydride, glurar anhydride, 3-methylglutaric acid. anhydride. 2,2-dimethylsuccinic anhydride, cyclic alkylcarboxylic acid anhydrides, cyclic alkenylcarboxylic anhydrides, alkenylsuccinic anhydrides (ASA), chloroacetic acid, salts of chloroacetic acid, bromoacetic acid, salts of bromoacetic acid, halogen-substituted alkanoic acid acrylamides and halogen-substituted alkenyl acrylamides.

Such alkylating agents are selected from 3-chloro-2-hydroxypropyltrimethylammonium chloride, 2- (diethylamino) ethyl chloride hydrochlorides, (dialkylamino) alkyl chlorides such as 2- (dimethylamino) ethyl chloride, 3-chloro-2-hydroxypropylalkyl-dimethylammonium chlorides such as 3-chloro 2-hydroxypropyl lauryldimethylammonium chloride, 3-chloro-2-hydroxypropyl-cocoalkyldimethylammonium chloride, 3-chloro-2-hydroxypropylstearyldimethylammonium chloride, (haloalkyl) trimethylammonium chlorides such as (4-chlorobutyl) trimethylammonium chloride, (6-chlorohexyl) trimethylammonium chloride, (8- Chloroctyl) trimethylammonium chloride and glycidylpropyl) trimethylammonium chlorides. (F) Hofmann degradation of homopolymers or copolymers of (meth) acrylamide

Other suitable polymers with primary amino groups are the reaction products which can be obtained by Hofmann degradation of homopolymers or copolymers of acrylamide or methacrylamide in an aqueous medium in the presence of sodium hydroxide solution and sodium hypochlorite and subsequent decarboxylation of the carbamate groups of the reaction products in the presence of an acid , Such polymers are for example from EP-A 0 377 313 and

WO 2006/0751 15 known. The preparation of polymers containing vinylamine groups is discussed in detail, for example, in WO 2006/0751 15, page 4, line 25 to page 10, line 22 and in the examples on pages 13 and 14. The information given there applies to the characterization of the polymers containing vinylamine units prepared by Hofmann degradation. The polymer content without counterion and the content of the amino groups of this type of polymers is determined in a manner known per se by means of polyelectrolyte titration and NMR measurements.

It is based on polymers containing acrylamide and / or methacrylamide units. These are homopolymers or copolymers of acrylamide and methacrylamide. Suitable comonomers are, for example, dialkylaminoalkyl (meth) acrylamides, diallylamine, methyldiallylamine and also the salts of the amines and the quaternized amines. Also suitable as comonomers are dimethyldiallylammonium salts, acrylamidopropyltrimethylammonium chloride and / or methacrylamidopropyltrimethylammonium chloride, N-vinylformamide, N-vinylacetamide, N-vinylpyrrolidone, vinyl acetate and acrylic and methacrylic acid esters. When

Comonomers are also optionally anionic monomers such as acrylic acid, methacrylic acid, maleic anhydride, maleic acid, itaconic acid, acrylamidomethylpropanesulfonic acid, methylallyl sulfonic acid and vinylsulfonic acid and the alkali metal, Erdalkylimetall- and ammonium salts of said acidic monomers into consideration. The amount of water-insoluble monomers is chosen in the polymerization so that the resulting polymers are soluble in water. If appropriate, comonomers may also be used crosslinkers, for. B. ethylenically unsaturated monomers which contain at least two double bonds in the molecule such as triallylamine, methylenebisacrylamide, ethylene glycol diacrylate, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, triallylamine and Trimethyloltrimethacry-Iat. If a crosslinker is used, the amounts used are, for example, 5 to 5000 ppm. The polymerization of the monomers can be carried out by any known method, for. B. by free-radical initiated solution, precipitation or suspension polymerization. If appropriate, it is possible to work in the presence of customary polymerization regulators. When Hofmann degradation is for example from 20 to 40 wt .-% aqueous solutions of at least one acrylamide and / or methacrylamide units containing polymers. The ratio of alkali metal hypochlorite to (meth) acrylamide units in the polymer is decisive for the resulting content of amine groups in the polymer. The molar ratio of alkyl metal hydroxide to alkyl metal hypochlorite is, for example, 2 to 6, preferably 2 to 5. For a certain amine group content in the degraded polymer, the amount of alkali metal hydroxide required for the degradation of the polymer is calculated.

The Hofmann degradation of the polymer takes place z. In the temperature range of 0 to 45 ° C, preferably 10 to 20 ° C in the presence of quaternary ammonium salts as a stabilizer to prevent side reaction of the resulting amino groups with the amide groups of the starting polymer. After completion of the reaction with alkyllauge / alkali metal hypochlorite, the aqueous reaction solution is passed into a reactor in which an acid for the decarboxylation of the reaction product is initially introduced. The pH of the reaction product containing vinylamine units is adjusted to a value of 2 to 7. For example, the concentration of the degradation product containing vinylamine units is more than

3.5 wt .-%, usually it is above 4.5 wt .-%. The aqueous polymer solutions can be concentrated, for example, by means of ultrafiltration.

Further suitable polymers having primary amino groups are ethyleneimine units-containing polymers (G). They typically have a mixture of primary, secondary and tertiary amino groups. The content of the amino groups and their distributions to primary, secondary and tertiary amino groups of polymers containing ethyleneimine units are determined in a manner known per se by means of NMR. The polymers containing ethyleneimine units include all polymers obtainable by polymerization of ethyleneimine in the presence of acids, Lewis acids or haloalkanes, such as homopolymers of ethyleneimine or graft polymers of ethyleneimine, cf. US 2,182,306 or in US 3,203,910. If desired, these polymers can subsequently be subjected to crosslinking. As crosslinkers z. For example, all multifunctional compounds which contain reactive groups with respect to primary amino groups include, for example, multifunctional epoxides such as bisglycol ethers of oligo- or polyethylene oxides or other multifunctional alcohols such as glycerol or sugars, multifunctional carboxylic acid esters, mulifunctional isocyanates, polyfunctional acrylic or methacrylic acid esters, multifunctional Acrylic or methacrylic acid amides, epichlorohydrin, multifunctional acid halides, multifunctional nitriles, α, ω-chlorohydrin ethers of oligo- or polyethylene oxides or other multifunctional alcohols such as glycerol or sugars, divinylsulfone, maleic anhydride or ω-halocarboxylic acid chlorides, multifunctional haloalkanes especially α, ω- Dichloroalkanes. Further crosslinkers are described in WO 97/25367, pages 8 to 16.

For example, polymers containing ethyleneimine units are known from EP-A-041 1400,

DE 2434816 and US 4,066,494. The content of primary amino groups is usually 10 to 40 mol% in the described ethyleneimine-containing polymers.

As (b) ethyleneimine units containing polymers used z. B. in the inventive method, at least one water-soluble cationic polymer from the group of

Homopolymers of ethyleneimine,

polyethylenimines reacted with at least bifunctional crosslinkers,

polyethyleneamines grafted with ethyleneimine and reacted with at least bifunctional crosslinkers,

Reaction products of polyethylenimines with monobasic carboxylic acids to amidated polyethylenimines,

Michael addition products of polyethyleneimines to ethylenically unsaturated acids, salts, esters, amides or nitriles of monoethylenically unsaturated carboxylic acids, phosphonomethylated polyethyleneimines,

carboxylated polyethyleneimines and

alkoxylated polyethyleneimines.

Polymers which are obtained by first condensing at least one polycarboxylic acid with at least one polyamine to form polyamidoamines, then grafting with ethyleneimine and then crosslinking the reaction products with one of the above-mentioned compounds belong to the compounds preferably containing ethyleneimine units. A method for producing such compounds is, for example, in

DE-A-2434816 described, wherein α, ω-chlorohydrin ethers of oligo- or polyethylene oxides are used as crosslinking agents.

Such ultrafiltered products are described in detail in WO 00/67884 and WO 97/25367.

Reaction products of polyethyleneimines with monobasic carboxylic acids to amidated polyethyleneimines are known from WO 94/12560. Michael addition products of polyethyleneimines to ethylenically unsaturated acids, salts, esters, amides or nitriles of mono- ethylenically unsaturated carboxylic acids are the subject of WO 94/14873. Phosphonomethylated polyethyleneimines are described in detail in WO 97/25367. Carboxylated polyethyleneimines are, for example, by means of a streamer synthesis by reaction of polyethyleneimines with formaldehyde and ammonia / hydrogen cyanide and hydrolysis of the reaction available. Alkoxylated polyethyleneimines can be prepared by reacting polyethylenimines with alkylene oxides, such as ethylene oxide and / or propylene oxide.

The polymers containing ethyleneimine units have, for example, molecular weights of from 10,000 to 3,000,000. The cationic charge of the polymers containing ethyleneimine units is e.g. at least 4 meq / g. It is usually in the range of 8 to 20 meq / g.

The polymers having primary amino groups and / or amidine units also include hydrolyzed graft polymers of, for example, N-vinylformamide on polyalkylene glycols, polyvinyl acetate, polyvinyl alcohol, polyvinylformamides, polysaccharides such as starch, oligosaccharides or monosaccharides. The graft polymers are obtainable by free-radically polymerizing, for example, N-vinylformamide in aqueous medium in the presence of at least one of the stated grafting bases together with copolymerizable other monomers and then hydrolyzing the grafted vinylformamide units in a known manner. Such graft polymers are described, for example, in DE-A-19515943, DE-A-4127733, DE-A-1004121 1.

Furthermore, suitable polymers with primary amino groups and polymethyleneamines, as described in DE 10233930 and 10305807 are suitable.

It is likewise possible to use polycondensates which carry primary amino groups, such as polylysine, polyallylamines or polysaccharides which have primary amino groups, such as chitosan, as polymers having primary amino groups. The aqueous composition according to the invention is prepared by combining the individual components. As a rule, the aqueous solution of the polymer having primary amino groups and / or amidine groups is prepared, adjusted to a pH <6 at which crosslinking occurs to an insignificant extent, and the 1,4-cyclohexanedione is used as Solid substance too. Alternatively, the addition of the 1, 4-cyclohexanedione can also be carried out as an aqueous solution. According to another embodiment, it is possible to add the solution of the polymer having primary amino groups and / or amidine groups to the 1,4-cyclohexanedione which has been adjusted to the pH <6. However, preference is given to adding the 1,4-cyclohexanedione to the solution of the polymer having primary amino groups and / or amidine groups. The preparation of the mixture is preferably carried out at room temperature, but may optionally also be carried out at reduced temperatures to 0 ° C. Likewise, the preparation of the mixture can also be carried out at elevated temperature up to 100 ° C. Preferably, the addition is at room temperature.

For mixing all commercially available mixing units can be used, which can handle the viscosities of the polymer solutions. The mixing process should be carried out at least until a homogeneous aqueous composition is present. If 1, 4-cyclohexadione was used as a solid, the mixing process should be continued until the 1, 4-Cyclolhexadion has completely dissolved. It is beneficial to stir for at least one hour, but is not mandatory. It is also possible to mix 1, 4-cyclohexanedione as an aqueous solution in line in the solution of the polymer having primary amino groups and / or amidine groups.

The aqueous composition contains polymers having primary amino groups and / or amidine groups with a total content of these groups of> 1.5 meq / g of polymer (milliequivalent / gram of polymer). Preference is given to a total content of primary amino groups and / or amidine groups of 3 to 32 meq / g of polymer, in particular of 5 to 23 meq / g of polymer.

Based on the total amount of primary amino groups and amidine groups of the polymers are 0.01 to 50 mol%, preferably 0.1 to 30 mol%, in particular 0.2 to 15 mol%, 1, 4-Clohexhexandion used.

The aqueous composition according to the invention preferably contains

(A) 5 to 40 wt .-% based on the aqueous composition polymers having primary amino groups and / or amidine groups with a total content of primary amino groups and / or amidine groups of> 1, 5 meq / g of polymer and

(B) 0.1 to 30 mol% of 1, 4-cyclohexanedione (b) based on the total amount of primary amino groups and amidine groups of these polymers. Preference is given to aqueous composition according to the invention consisting of at least 95% by weight, in particular consisting of 100% by weight,

(a) 5 to 40% by weight, based on the aqueous composition, of polymers having primary amino groups and / or amidine groups with a total content of these groups of a1.5 meq / g of polymer,

(B) 0.1 to 30 mol% of 1, 4-cyclohexanedione (b) based on the total amount of primary amino groups and / or amidine groups of these polymers

and water. The present invention further relates to the use of the aqueous composition according to the invention as a solidifying agent in the process for the production of paper and board by increasing the pH by at least one stage.

The use of the aqueous composition according to the invention as solidifying agent is preferably carried out in the wet end. The addition can take place both to the filler, to the pulp or to the pulp. Preferably, the addition to the stock takes place before sheet formation. The present invention further relates to a process for producing paper and board by adding the aqueous mixture according to the invention to a paper stock having a pH in the range of 6 to 8 and subsequent dewatering of the paper stock with sheet formation and drying. Furthermore, the present invention relates to the paper and board produced by this method. Particularly preferred is a process for the preparation of testliners and wood-free papers.

Depending on the area-related mass, colloquially also referred to as basis weight, the name changes for the molded body made of fiber. In the following, paper is to be understood as meaning a weight per unit area of 7 g / m ² to 225 g / m ² and, under paperboard, a basis weight of more than 225 g / m ² .

The term paper stock (also referred to as pulp) is understood below to mean a mixture of substances suspended in water and consisting of one or more types of processed fibers and of various auxiliaries, prior to sheet formation. Depending on the stage in the production process of the paper, the paper stock thus additionally contains the composition according to the invention, optionally filler and optionally paper auxiliaries. If it is a reference to dry paper stock, the total paper pulp of pulp, composition used according to the invention, optionally filler and optionally paper auxiliaries without water to understand (pulp solid).

Suitable fillers are all pigments customarily used in the paper industry on the basis of metal oxides, silicates and / or carbonates, in particular of pigments from the group consisting of calcium carbonate used in the form of ground (GCC) lime, chalk, marble or precipitated calcium carbonate (PCC) talc, kaolin, bentonite, satin white, calcium sulfate, barium sulfate and titanium dioxide. It is also possible to use mixtures of two or more pigments.

The inventive method is used to produce paper and cardboard comprising dewatering a filler-containing paper stock. The filler content of the paper or the cardboard can be 5 to 40 wt .-% based on the paper or cardboard.

According to a preferred embodiment, a process for the production of paper is preferred whose filler content is 20 to 30 wt .-%. Such papers are, for example, wood-free papers.

According to a further preferred embodiment, a method for the production of paper is preferred whose filler content is 5 to 20 wt .-%. Such papers are used primarily as packaging papers.

According to a further preferred embodiment, a process for the production of paper is preferred whose filler content is 5 to 15 wt .-%. Such papers are used primarily for newspaper printing. According to another preferred embodiment, preference is given to a process for producing paper whose filler content is from 25 to 40% by weight, for example SC papers.

According to the invention, native and / or recovered fibers can be used as the fibrous material. All fibers of coniferous and hardwoods commonly used in the paper industry can be used, for example. Pulp, bleached and unbleached pulp and pulp from all annual plants. Wood pulp includes, for example, groundwood, thermo-mechanical pulp (TMP), chemo-thermo-mechanical pulp (CTMP), pressure groundwood, semi-pulp, high yield pulp and refiner mechanical pulp (RMP). As pulp, for example, sulphate, sulphite and soda pulps come into consideration. Preferably, unbleached pulp, also referred to as unbleached kraft pulp, is used. Suitable annual plants for the production of fibrous materials are for example rice, wheat, sugarcane and kenaf. Waste paper may also be used to make the pulps, either alone or blended with other pulps. For example, the waste paper can come from a deinking process. But it is not necessary that the waste paper to be used is subjected to such a process. Furthermore, it is also possible to start from fiber blends of a primary material and recycled coated broke.

In the case of bleached or unbleached pulp, a pulp having a freeness of 20 to 30 SR can be used. In general, a pulp with a freeness of about 30 SR is used, which is ground during the production of the pulp. Preferably, pulp is used which has a freeness of <30 SR.

The treatment of the pulp with the aqueous composition according to the invention is carried out in aqueous suspension. With the exception of cationic starch, the treatment of the pulp is preferably in the absence of other process chemicals commonly used in papermaking. It takes place in the papermaking process by adding the aqueous composition of the invention to an aqueous paper stock, preferably at a pulp concentration of 20 to 40 g / l. Particularly preferred is a process variant in which the aqueous composition according to the invention is added to the aqueous paper stock at a time which is before the addition of the filler.

According to a further preferred embodiment, the addition of the aqueous composition according to the invention to the thin material takes place, that is to say at a fiber concentration of 5 to 15 g / l.

The aqueous compositions according to the invention are preferably added in an amount of from 0.01 to 6% by weight of the polymer having primary amino groups and / or amidine groups (solid), based on pulp (solid). Particularly preferably, the aqueous composition is used in a ratio to the pulp, which is 0.05 to 5 wt .-% of the polymer having primary amino groups and / or amidine (solids) based on the pulp (solid). The dry content of the paper and pulp is the ratio of the mass of a sample which has been dried at a temperature of (105 ± 2) ° C under defined conditions to a constant mass to the mass of the sample before drying. The dry content is usually given as percentage by mass. The determination of the dry content is carried out according to DIN EN ISO 638 DE with the oven cabinet method. From the dry content of the pulp, the amount of pulp (solid) can be determined.

Typical application rates of the aqueous composition according to the invention are, based on the polymer, for example 0.2 to 50 kg, preferably 0.3 to 10 kg, in particular 0.5 to 50 kg of at least the polymer having primary amino groups and / or amidine groups, per ton of a dry pulp , With particular preference, the amounts of the aqueous composition of the invention based on the polymer having primary amino groups and / or amidine groups is from 0.4 to 3 kg, preferably from 0.6 to 3 kg of polymer (solid), per ton of dry pulp.

The reaction time of the aqueous composition according to the invention on a pure pulp or pulp after metering to sheet formation is, for example, 0.5 seconds to 2 hours, preferably 1.0 seconds to 15 minutes, particularly preferably 2 to 20 seconds.

According to the invention fillers having an average particle size (volume average) ^ 10 μηη, preferably from 0.3 to 5 μηη, in particular from up to 0.5 to 2 μηη used. The determination of the average particle size (volume average) of the fillers and of the particles of the powder composition is carried out in the context of this document generally by the method of quasi-elastic light scattering (DIN-ISO 13320-1), for example with a Mastersizer 2000 from. Malvern Instruments Ltd. The filler is preferably metered after the addition of the aqueous composition according to the invention. In this case, according to a preferred embodiment, the addition takes place in the stage in which the pulp is already present as a thin material, ie at a pulp concentration of 5 to 15 g / l. According to a further preferred embodiment, the filler is metered both in the thin and in the thick matter, wherein the ratio of the two addition amounts (addition of thick material / addition of thin material) is preferably from 5/1 to 1/5.

In addition to the aqueous composition according to the invention, customary paper auxiliaries can optionally be mixed with the paper stock, generally at a pulp concentration of 5 to 15 g / l. Conventional paper auxiliaries are, for example, sizing agents, wet strength agents, cationic or anionic retention aids based on synthetic polymers, and dual systems, dehydrating agents, other dry strength agents, optical stabilizers. lers, defoamers, biocides and paper dyes. These conventional paper additives can be used in the usual amounts.

The sizing agents to be mentioned are alkylketene dimers (AKD), alkenylsuccinic anhydrides (ASA) and rosin size.

Suitable retention agents are, for example, cationic polyacrylamides, cationic starch, cationic polyethylenimine or cationic polyvinylamine. In order to achieve a high retention of filler, it is recommended to add retention aids of this kind, which can be added to the thick material, but also to the thin material, for example.

Dry strength agents are synthetic dry strength agents such as polyvinylamine, polyethyleneimine, glyoxylated polyacrylamide (PAM), or natural dry strength agents such as starches based on derivatized starches (cationic) or natural starches which are oxidatively or enzymatically degraded. In order to achieve a high degree of effectiveness of the dry strength agents, the addition of synthetic dry strength agents is recommended, which can preferably be added to the thick stock but also to the thin stock.

The papers obtained with the aqueous composition according to the invention show very good performance properties. The addition of the aqueous composition of the invention results in excellent strengths, especially dry strength. The allows the same grammage and desired strength, the use of smaller amounts of auxiliaries or the production of paper with lower grammage while maintaining strength and thus a reduction in basis weight. Furthermore, due to higher solidifying effect, the use of less expensive fibers is possible (eg increase of waste paper content in semi-kraft kraftliner or increase of the chemo-thermal pulp in cartons or food cartons), increase the filler content in packaging papers and graphic papers. Preference is given to using aqueous compositions containing, as polymer having primary amino groups and / or amidine groups, a hydrolyzed homopolymer of N-vinylcarboxamide, preferably having a degree of hydrolysis of 30 mol%, for the preparation of testliners. According to a likewise preferred embodiment, aqueous compositions containing a polymer having primary amino groups and / or amidine groups are selected from hydrolyzed copolymers of N-vinylcarboxamide and other neutral monoethylenically unsaturated monomers, hydrolyzed copolymers of N-vinylcarboxamide and anionic monoethylenically unsaturated monomers, hydrolyzed copolymers of N-Vinylcarbonsäureamid and cationic monoethylenically unsaturated monomers, used for the production of wood-free papers. Particular preference is given to aqueous compositions comprising as polymer having primary amino groups and / or amidine groups a partially or fully hydrolyzed copolymers of N-vinylcarboxamide with further neutral, anionic and / or cationic monoethylically unsaturated monomers, this monomer being selected from acrylonitrile, vinyl acetate , Sodium acrylate, diallyldimethylammonium chloride, [3- (dimethylamino) propyl] acrylamide, N- [3- (dimethylamino) propyl] methacrylamide, [3- (trimethylammonium) propyl] acrylamido chloride and N- [3- (trimethylammonium) propyl] methacrylamide chloride Production of woodfree papers used. Particular preference is given to using aqueous compositions of the invention comprising as polymer having primary amino groups and / or amidine groups a partially or fully hydrolyzed copolymers of N-vinylcarboxamide with sodium acrylate and a degree of hydrolysis of 30 mol%, for the production of wood-free papers. It is believed, without being bound by theory, that the underlying equilibrium of polymer having primary amino groups and / or amidine groups + cyclohexanedione and the crosslinked product of these two substances at a pH above 6, shifted to the side of the crosslinked product becomes. According to this theory, such an equilibrium shift in the presence of the pulp in papermaking, where there is a pH above, would cause solidification.

Examples

The following examples are intended to explain the present invention in more detail. The percentages in the examples are by weight unless otherwise specified.

The following abbreviations are used below:

VFA: vinylformamide

NaAS: sodium acrylate

VAc: vinyl acetate

AN: acrylonitrile

DADMAC: diallyldimethylammonium chloride

PVFA: polyvinylformamide

Copo VFA / NaAS: Copolymer of vinylformamide and sodium acrylate

Copo VFAA / Ac: Copolymer of vinylformamide and vinyl acetate

Copo VFA AN / Na itaconate: copolymer of vinylformamide, acrylonitrile, sodium itaconate

Copo VFA / NaAS / AN: Copolymer of vinylformamide, sodium acrylate and acrylonitrile

Copo VFA DADMAC: Copolymer of vinylformamide and DADMAC

The K values were measured according to H. Fikentscher, Cellulose Chemistry, Vol. 13, 48-64 and 71-74 under the particular conditions indicated. The figures in parenthesis indicate the concentration of the polymer solution and the solvent.

The percentages in the examples are by weight unless otherwise specified Solid contents of the polymers were determined by distributing 0.5 to 1.5 g of the polymer solution in a 4 cm diameter tin cover and then drying in a circulating air drying cabinet at 140 ° C. for two hours. The ratio of the mass of the sample after drying under the above conditions to the mass during sampling gives the solids content of the polymer.

The water used in the examples was completely desalted.

Preparation of the polymers with primary amino groups and / or amidine groups

The production took place in two or three steps:

1) polymerization

2) hydrolysis of the polymers and optionally

3) polymer-analogous reaction

1) Polymerizations

Table 1: Overview of the polymerizations

¹ > K value determined in formamide

2 ⁾ K value determined in DMSO

3> K value determined in water Example P1 (VFA homopolymer, K value 45)

Feed 1 provided 423.1 g of N-vinylformamide (BASF)

As feed 2 9.7 g of ^2,2'-azobis (2-methylpropionamidine) dihydrochloride (Wako) was dissolved in 1 12.0 g of water at room temperature.

A 2 l glass apparatus with anchor stirrer, descending condenser, internal thermometer and nitrogen inlet tube was charged with 585.2 g of water and 4.6 g of 75% strength by weight phosphoric acid. At a speed of 100 rpm, about 8.2 g of a 25% strength by weight sodium hydroxide solution were added, so that a pH of 6.6 was achieved. The initial charge was heated to 80 ° C. and the pressure in the apparatus was reduced to such an extent that the reaction mixture began to boil at 80 ° C. (about 460 mbar). Feeds 1 and 2 were then started simultaneously and dosed synchronously at a constant 80 ° C. over a period of 3 hours. After completion of the addition, the reaction mixture was postpolymerized at 80 ° C for three more hours. During the entire polymerization and postpolymerization about 100 g of water were distilled off. Subsequently, the batch was cooled to room temperature under normal pressure.

A slightly yellow, viscous solution with a solids content of 36.4% by weight was obtained. The K value of the polymer was 45 (1.0% by weight in water). Example P2 (VFA homopolymer, K value 90)

Feed 1 provided 234 g of N-vinylformamide.

The feed 2, 2 g of 2,2-azobis (2-methylpropionamidine) dihydrochloride were dissolved in water at room temperature 56.8 1 ^'. 1080.0 g of water and 2.5 g of 75% strength by weight phosphoric acid were placed in a 2 l glass apparatus with anchor stirrer, descending condenser, internal thermometer and nitrogen inlet tube. At a speed of 100 rpm, 2.1 g of a 25% strength by weight sodium hydroxide solution were added, so that a pH of 6.6 was reached. The initial charge is heated to 73 ° C and the pressure in the apparatus is reduced so much that the reaction mixture just boiled at 73 ° C (about 350 mbar). Then feeds 1 and 2 were started simultaneously. At constant 73 ° C, the feed 1 was metered in one hour and 15 minutes and the feed 2 in 2 hours. After completion of the addition of feed 2, the reaction mixture was postpolymerized for three more hours at 73 ° C. During the entire polymerization and postpolymerization about 190 g of water were distilled off. Subsequently, the batch was cooled to room temperature under normal pressure.

A slightly yellow, viscous solution with a solids content of 19.7% by weight was obtained. The K value of the polymer was 90 (0.5% by weight in water)

Example P3 (VFA homopolymer, K value 120)

The feed 1, 1 g of 2,2-azobis (2-methylpropionamidine) dihydrochloride were dissolved in 108.9 of water at room temperature for 1 ^'. 961.0 g of water and 2.4 g of 75% strength by weight phosphoric acid were placed in a 2 l glass apparatus with anchor stirrer, descending condenser, internal thermometer and nitrogen inlet tube. At a speed of 100 rpm, about 3.7 g of a 25 wt .-% sodium hydroxide solution was added, so that a pH of 6.6 was reached. Then, 222.2 g of N-vinylformamide was added. The initial charge was heated to 62 ° C and the pressure in the apparatus was reduced to about 220 mbar, so that the reaction mixture began to boil at 62 ° C. Feed 1 was metered in at a constant 62 ° C. in four hours. The mixture was then postpolymerized at 62 ° C. for two hours. During the entire polymerization and postpolymerization about 200 g of water were distilled off. The batch was then diluted under normal pressure with 670 g of water and cooled to room temperature.

This gave a slightly yellow, viscous solution with a solids content of 12.6 wt .-%. The K value of the polymer was 120 (0.1% strength by weight in 5% strength by weight aqueous NaCl solution).

Example P4 (VFA / Na acrylate copolymer 80 mol% / 20 mol%, K value 86)

Feed 1 was a mixture of 293.7 g of water, 242.96 g of aqueous 32% by weight Na acrylate solution adjusted to pH 6.4, and 237.2 g of N-vinylformamide.

The feed 2, 4 g of 2,2-azobis (2-methylpropionamidine) dihydrochloride were dissolved in 203.6 of water at room temperature for 1 ^'.

In a 2 l glass apparatus with anchor stirrer, descending condenser, internal thermometer and nitrogen inlet tube, 659.4 g of water and 3.5 g of 75 wt .-% phosphoric acid were placed. At a speed of 100 rpm, 6.0 g of a 25 wt .-% sodium hydroxide solution was added, so that a pH of 6.6 was reached. The original was heated to 80 ° C and reduced the pressure in the apparatus to about 460 mbar, so that the reaction mixture at 80 ° C just began to boil. Then feeds 1 and 2 were started simultaneously. At constant 80 ° C, the feed 1 was added in two hours and the feed 2 in 2.5 hours. After completion of the addition of feed 2, the reaction mixture was postpolymerized for a further 2.5 hours at 80.degree. During the entire polymerization and postpolymerization about 170 g of water were distilled off. Subsequently, the batch was cooled to room temperature under normal pressure.

This gave a slightly yellow, viscous solution with a solids content of 21, 5 wt .-%. The K value of the copolymer was 86 (0.5% strength by weight in 5% strength by weight aqueous NaCl solution). Example P5 (VFA Na acrylate copolymer = 70 mol% / 30 mol%, K value 55 )

Feed 1 was a mixture of 147.3 g of water, 317.6 g of aqueous 32% by weight Na acrylate solution adjusted to pH 6.4, and 18.1 g of N-vinylformamide.

As feed 2 were 5.1 g of ^2,2-azobis (2-methylpropionamidine) dihydrochloride dissolved in 165.9 of water at room temperature.

573.4 g of water and 3.0 g of 75% strength by weight phosphoric acid were placed in a 2 l glass apparatus with anchor stirrer, descending condenser, internal thermometer and nitrogen inlet tube. At a speed of 100 rpm, 5.2 g of a 25 wt .-% sodium hydroxide solution was added, so that a pH of 6.6 was reached. The original was heated to 80 ° C and reduced the pressure in the apparatus to about 460 mbar, so that the reaction mixture at 80 ° C just began to boil. Then feeds 1 and 2 were started simultaneously. At constant 80 ° C, the feed 1 was added in two hours and the feed 2 in 2.5 hours. After completion of the addition of feed 2, the reaction mixture was re-polymerized at 80 ° C. for a further 2.5 hours. During the entire polymerization and postpolymerization about 170 g of water were distilled off. Subsequently, the batch was cooled to room temperature under normal pressure.

A slightly yellow, viscous solution with a solids content of 24.0% by weight was obtained. The K value of the copolymer was 55 (0.5% by weight in 5% strength by weight aqueous NaCl solution).

Example P6 (copolymer VFA Na acrylate = 70 mol% / 30 mol%). As feed 1, a mixture of 340.0 g of water, 176.5 g of aqueous 32% Na acrylate solution, which had been adjusted to pH 6.4, and 100.6 g of N-vinylformamide.

As feed 2 5.8 g of ^2,2'-azobis (2-methylpropionamidine) dihydrochloride were dissolved in 164.2 g of water at room temperature.

As feed 3 5.8 g of ^2,2'-azobis (2-methylpropionamidine) dihydrochloride were dissolved in 164.2 g of water at room temperature.

380 g of water and 1.2 g of 85% strength by weight phosphoric acid were placed in a 2 l glass apparatus with anchor stirrer, descending condenser, internal thermometer and nitrogen inlet tube. At a speed of 100 rpm, 4.2 g of a 25 wt .-% sodium hydroxide solution was added, so that a pH of 6.6 was reached. The original is heated to 80 ° C and the pressure in the apparatus reduced to about 450 mbar, so that the reaction mixture at 80 ° C just began to boil. Then feeds 1 and 2 were started simultaneously and dosed synchronously in 2 hours. The mixture was then postpolymerized for a further hour at 80 ° C. Thereafter, the feed 3 was added in 5 minutes and further polymerized at 80 ° C. for a further two hours. During the entire polymerization and postpolymerization, about 100 g of water were distilled off. Subsequently, the batch was cooled to room temperature under normal pressure.

A slightly yellow, viscous solution with a solids content of 16.0% by weight was obtained. The K value of the copolymer was 85 (determined to be 0.5% by weight in 5% strength by weight aqueous NaCl). Example P7 (copolymer VFA Na acrylate = 70 mol% / 30 mol%, K value 90)

Feed 1 was a mixture of 100.0 g of water, 224.6 g of aqueous 32 wt .-% sodium acrylate solution, which was adjusted to pH 6.4, and 128.0 g of N-vinylformamide provided as feed 2 azobis (2-methylpropionamidine) dihydrochloride was added 0.9 g of 2,2 ^'dissolved in 125.8 g of water at room temperature.

407 g of water and 1.9 g of 85% strength by weight phosphoric acid were placed in a 2 l glass apparatus with anchor stirrer, descending condenser, internal thermometer and nitrogen inlet tube. At a speed of 100 rpm about 3.7 g of a 25 wt .-% sodium hydroxide solution was added, so that a pH of 6.6 was reached. The original is heated to 80 ° C and the pressure in the apparatus reduced to about 450 mbar, so that the reaction mixture at 80 ° C just began to boil. Then feeds 1 and 2 were started simultaneously. At constant 80 ° C, the feed 1 was metered in in 1.5 hours and feed 2 in 2.5 hours. After completion of the addition of feed 2, the reaction mixture was postpolymerized for a further 2.5 hours at 80.degree. During the entire polymerization and postpolymerization about 143 g of water were distilled off. Subsequently, the batch was cooled to room temperature under normal pressure. Obtained was a yellow, viscous solution with a solids content of 23.8 wt .-%. The K value of the copolymer was 90 (0.5% by weight in 5% strength by weight aqueous NaCl solution).

Example P8 (copolymer VFA Na acrylate = 70 mol% / 30 mol%)

Feed 1 was a mixture of 330 g of water, 217.8 g of aqueous 32% by weight Na acrylate solution adjusted to pH 6.4, and 124.2 g of N-vinylformamide

As feed 2 0.3 g of 2,2-azobis (2-methylpropionamidine) dihydrochloride were ^'dissolved in 66.8 g of water at room temperature.

As feed 3 0.2 g of 2,2-azobis (2-methylpropionamidine) dihydrochloride were ^'dissolved in 17.4 g of water at room temperature.

A 2 l glass apparatus with anchor stirrer, descending condenser, internal thermometer and nitrogen inlet tube was charged with 668.3 g of water and 1.9 g of 75% strength by weight phosphoric acid. At a speed of 100 rpm, 3.1 g of a 25 wt .-% sodium hydroxide solution was added, so that a pH of 6.6 was reached. The original was heated to 73 ° C and the pressure in the apparatus reduced to about 340 mbar, so that the reaction mixture at 73 ° C just began to boil. Then feeds 1 and 2 were started simultaneously. At constant 73 ° C, the feed 1 was added in two hours and the feed 2 in 3 hours. After completion of the addition of feed 2, the reaction mixture was postpolymerized for 2 more hours at 73 ° C. Then, the feed 3 was added in 5 minutes and further polymerized at 73 ° C. for a further two hours. During the entire polymerization and postpolymerization about 190 g of water were distilled off. Subsequently, the batch was cooled to room temperature under normal pressure.

A slightly yellow, viscous solution with a solids content of 15.9% by weight was obtained. The K value of the copolymer was 122 (0.1% strength by weight in 5% strength by weight aqueous NaCl solution).

Example P9 (Copolymer VFA Na acrylate = 60 mol% / 40 mol%, K value 92)

Feed 1 was a mixture of 423.5 g aqueous 32 wt% Na acrylate solution adjusted to pH 6.4 and 155.1 g N-vinylformamide

As feed 2 2.1 g of 2,2-azobis (2-methylpropionamidine) dihydrochloride were ^'dissolved in 227.9 g of water at room temperature. 573.4 g of water and 3.0 g of 85% strength by weight phosphoric acid were placed in a 2 l glass apparatus with anchor stirrer, descending condenser, internal thermometer and nitrogen inlet tube. At a speed of 100 rpm, 5.2 g of a 25 wt .-% sodium hydroxide solution was added so that a pH of 6.6 was reached. The initial charge is heated to 77 ° C and the pressure in the apparatus is reduced to about 450 mbar, so that the reaction mixture begins to boil at 77 ° C. Then feeds 1 and 2 were started simultaneously. At constant 77 ° C, the feed 1 in 1, 5 hours and the feed 2 in 2.5 hours added. After completion of the addition of feed 2, the reaction mixture was postpolymerized for a further 2.5 hours at 80.degree. During the entire polymerization and postpolymerization, about 200 g of water were distilled off. Subsequently, the batch was cooled to room temperature under normal pressure. This gave a slightly yellow, viscous solution with a solids content of 25.0 wt .-%. The K value of the copolymer was 92 (0.5% by weight in 5% strength by weight aqueous NaCl solution).

Example P10 (copolymer VFA / VAc = 70 mol% / 30 mol%, K value 84)

Feed 1 provided 76.5 g of vinyl acetate

As feed 2 0.4 g of 2,2-azobis (2-methylpropionamidine) dihydrochloride were ^'dissolved in 98.2 g of water at room temperature.

As feed 3 0.1 g of 2,2-azobis (2-methylpropionamidine) dihydrochloride were ^'dissolved in 44.7 g of water at room temperature.

As feed 4 750 g of water were provided

In a 2 l glass apparatus with anchor stirrer, reflux condenser, internal thermometer and nitrogen inlet tube, 352.5 g of water, 2.2 g of 85% strength by weight phosphoric acid and 22.4 g of a 10% strength by weight aqueous Mowiol 44-88 solution were initially charged. At a speed of 100 rpm, 4.0 g of a 25% strength by weight sodium hydroxide solution were added in such a way that a pH of 6.5 was reached. Into the initial charge, 149.0 g of N-vinylformamide was added and nitrogen was introduced at 3 1 / h for half an hour to remove the oxygen present. Meanwhile, the original was heated to 65 ° C. Then the feed 1 was added in 5 minutes and then the feed 2 in 5 h. 1, 0 h after the start of the feed 2, the feed 4 is additionally started and added in 2.5 hours. After the end of feed 2, polymerization was continued at 65 ° C. for one hour, then feed 3 was added in 5 minutes, and the reaction mixture was heated to 70 ° C. At this temperature, polymerization was continued for a further 2 hours. Thereafter, the reflux condenser is replaced by a descending radiator. The pressure in the apparatus was lowered to 580 mbar and distilled off at 80 ° C about 68 g of water. At atmospheric pressure, the product was cooled to room temperature.

A finely divided, white suspension having a solids content of 15.5% by weight was obtained. The K value of the copolymer was 84 (0.5 wt% in formamide)) Example P1 1 (copolymer VFA / VAc = 60 mol% / 40 mol%, K value 74)

Feed 1 provided 100.1 g of vinyl acetate

As Feed 4, 750 g of water were provided. In a 2 l glass apparatus with anchor stirrer, reflux condenser, internal thermometer and nitrogen inlet tube, 352.8 g of water, 2.2 g of 85% by weight phosphoric acid and 22.4 g of a 10% by weight were added. aqueous Mowiol 44-88 solution. At a speed of 100 rpm, 4.0 g of a 25 wt .-% sodium hydroxide solution was added, so that a pH of 6.5 was reached. 125.2 g of N-vinylformamide were added to the initial charge and nitrogen was introduced at 3 1 / h for half an hour in order to remove the oxygen present. Meanwhile, the original was heated to 65 ° C. Then the feed 1 was added in 5 minutes and then the feed 2 in 5 hours. 1.5 hours after the start of feed 2, feed 4 is additionally started and added in 2.5 hours. After the end of feed 2, polymerization was continued at 65 ° C. for 1 hour, then feed 3 was added in 5 minutes and the reaction mixture was heated to 70 ° C. At this temperature, polymerization was continued for a further two hours. Thereafter, the reflux condenser is replaced by a descending radiator. The pressure in the apparatus was lowered to 540 mbar and distilled off at 80 ° C about 102 g of water. At atmospheric pressure, the product was cooled to room temperature.

A finely divided, white suspension having a solids content of 15.7% by weight was obtained. The K value of the copolymer was 74 (0.5% by weight in formamide))

Example P12 (Copolymer VFA / VAc = 50 mol% / 50 mol%, K value 68)

Feed 1 was 127.3 g of vinyl acetate

As feed 2 were 0.5 g of ^2,2-azobis (2-methylpropionamidine) dihydrochloride in 101 g of water dissolved 8 at room temperature.

As feed 3 0.1 g of 2,2-azobis (2-methylpropionamidine) dihydrochloride were ^'dissolved in 46.4 g of water at room temperature.

As feed 4 750 g of water were provided

338.4 g of water, 2.2 g of 85% strength by weight phosphoric acid and 23.2 g of a 10% strength by weight aqueous Mowiol 44-88 solution were initially taken in a 2 l glass apparatus with anchor stirrer, reflux condenser, internal thermometer and nitrogen inlet tube. At a speed of 100 rpm, 4.0 g of a 25 wt .-% sodium hydroxide solution was added, so that a pH of 6.5 was reached. Then, 106.2 g of N-vinylformamide was added to the receiver and nitrogen was introduced at 3 1 / h for half an hour to remove the oxygen present. Meanwhile, the original was heated to 65 ° C. Then the feed 1 was added in 5 min and then the feed 2 in 5 h. 2h after the start of feed 2, feed 4 was also added started and added in 2.5 h. After the end of feed 2, polymerization was continued at 65 ° C. for 1 h, then feed 3 was added in 5 min and the reaction mixture was heated to 70 ° C. At this temperature, polymerization was continued for a further two hours. Thereafter, the reflux condenser is replaced by a descending radiator. The pressure in the apparatus was lowered to 540 mbar and distilled off at 80 ° C about 200 g of water. The vacuum was broken and the product cooled to room temperature.

A finely divided, white suspension having a solids content of 16.5% by weight was obtained. The K value of the copolymer was 68 (0.5 wt% in formamide)) Example P13 (copolymer VFA AN / Na itaconate = 49.5 mol% / 49.5 mol% / 1.0 mol%, K value 175)

Feed 1 provided 221.3 g of acrylonitrile

Feed 2 provided 299.3 g of N-vinylformamide

As feed 3 0.7 g of 2,2-azobis (2-methylpropionamidine) dihydrochloride were ^'dissolved in 128.8 g of water at room temperature.

In a 2 l glass apparatus with anchor stirrer, reflux condenser, internal thermometer and nitrogen inlet tube, 1600.0 g of water, 5.2 g of 75% strength by weight phosphoric acid, 26.0 g of Luviskol K90 (polyvinylpyrrolidone, BASF) and 154.7 g of a 7% by weight % aqueous Itaconsäurelösung submitted. At a speed of 100 rpm, 37.4 g of a 25 wt .-% sodium hydroxide solution was added so that a pH of 6.8 was reached. Nitrogen was introduced into the receiver at 10 l / h for half an hour to remove the oxygen present. Meanwhile, the original was heated to 60 ° C. Then feeds 1 to 3 were started simultaneously. At constant 60 ° C., feed 1 was metered in in 3.5 hours, feed 2 in three hours and feed 3 in 4 hours. Then, the reaction mixture was postpolymerized at 60 ° C for a further 2.5 hours.

Subsequently, 546 g of water were added and the reflux condenser was replaced by a descending condenser. The pressure in the apparatus was lowered to 220 mbar and distilled off at 64 ° C 552 g of water. At atmospheric pressure, the product was cooled to room temperature.

A finely divided, white suspension having a solids content of 16.3% by weight was obtained. The K value of the copolymer was 175 (0.1% by weight in DMSO))

Example P14 (copolymer VFA / Na acrylate / AN = 50 mol% / 30 mol% / 20 mol%, K value 90)

As feed 1, 342.7 g of a 32% strength by weight aqueous Na acrylate solution were provided. As feed 2, 139.5 g of N-vinylformamide were provided

Feed 3 provided 41.2 g of acrylonitrile

As feed 4, 0 g of ^2,2'-azobis (2-methylpropionamidine) dihydrochloride were dissolved in 1 1 14.8 g of water at room temperature.

A 2 l glass apparatus with anchor stirrer, reflux condenser, internal thermometer and nitrogen inlet tube was charged with 540.0 g of water and 2.7 g of 75% strength by weight phosphoric acid. at At a speed of 100 rpm, 4.0 g of a 25% strength by weight sodium hydroxide solution were added in such a way that a pH of 6.7 was reached. Nitrogen was introduced into the receiver at 10 l / h for half an hour to remove the oxygen present. Meanwhile, the original was heated to 72 ° C. Then feeds 1 to 4 were started simultaneously. At constant 72 ° C, the feed 1 in two hours, the feed 2 in 1, 3 h, the feed 3 in 2.0 h and the feed 4 in three hours were added. The reaction mixture was then postpolymerized at 72 ° C. for a further 2.5 h.

Then, 121 g of water was added and the reflux condenser was replaced by a descending condenser. The pressure in the apparatus was lowered to 320 mbar and distilled off at 72 ° C 121 g of water. Under normal pressure, the product was cooled to room temperature.

This gave a slightly cloudy, viscous solution with a solids content of 25.6 wt .-%. The K value of the copolymer was 90 (0.5% by weight in 5% strength by weight aqueous NaCl solution). Example P15 (copolymer VFA DADMAC = 70 mol% / 30 mol%, K value 80)

Feed 1 provided 19.1 g of N-vinylformamide

As feed 2 2.1 g of 2,2-azobis (2-methylpropionamidine) dihydrochloride were ^'dissolved in 88.2 g of water at room temperature.

202.2 g of water and 2.2 g of 85% strength by weight phosphoric acid were placed in a 2 l glass apparatus with anchor stirrer, descending condenser, internal thermometer and nitrogen inlet tube. At a speed of 100 rpm, 3.0 g of a 25 wt .-% sodium hydroxide solution was added, so that a pH of 6.5 was reached. Subsequently, 176.8 g of a 65% strength by weight aqueous solution of diallyldimethylammonium chloride (Aldrich) were mixed in. Nitrogen was introduced into the receiver at 10 l / h for half an hour to remove the oxygen present. Meanwhile, the original was heated to 66 ° C. In the apparatus, the pressure was reduced to about 240 mbar, so that the reaction mixture at 66 ° C just boil began. Then feeds 1 and 2 were started simultaneously. At constant 66 ° C, the feed 1 was added in two hours and the feed 2 in 4 hours. After completion of the addition of feed 2, the reaction mixture was postpolymerized for a further hour at 66 ° C. Then, the pressure was increased to 360 mbar and the internal temperature to 75 ° C and then the mixture was further post-polymerized at 74 ° C for two hours. Under these conditions, the reaction mixture was still boiling. During the entire polymerization and postpolymerization, about 90 g of water were distilled off. Subsequently, 690 g of water were added, cooled under normal pressure, the approach to room temperature. A slightly yellow, viscous solution with a solids content of 20% was obtained. The K value of the copolymer was 80 (1% strength by weight in 5% strength by weight aqueous NaCl solution). 2. Hydrolyses

The hydrolyses described below in Examples H1 to H24 are summarized in Table 2. Table 2: Reaction conditions and polymer used for the hydrolysis

PG: polymer content without counterion

1> The degree of hydrolysis of vinyl acetate was> 95%

² > The required amount of acid was chosen so that the sodium acrylate units contained in the polymer were additionally protonated. ³ > The required amount of caustic soda was chosen so that the vinyl acetate units present in the molecule were completely hydrolyzed

4> The required amount of acid was chosen in such a way that the sodium ita conate units contained in the polymer were additionally protonated.

5> Amount of hydrolysis agent in mol% based on the molar amount of vinylformamide used for the starting polymer

⁶ > total content of prim. Amino groups and / or amidine units in 1 g of polymer without counterion

The degree of hydrolysis is the proportion in mol% of the hydrolyzed VFA units based on the VFA units originally present in the polymer.

The degree of hydrolysis of the hydrolyzed homopolymers or copolymers of N-vinylformamide was determined by enzymatic analysis of the formic acid / formates released during the hydrolysis (test set from Boehringer Mannheim).

Likewise, the degree of hydrolysis after hydrolysis of polymers carrying vinyl acetate units was determined on the basis of the liberated acetic acid / acetates using an analogous test set from Boehringer Mannheim.

The polymer content without counter-ions indicates the content of polymer in the aqueous solution in% by weight, counterions being ignored. It represents the sum of the parts by weight of all the structural units of the polymer in g which are present in 100 g of the solution. He is determined by calculation. In this case, potentially charge-carrying structural units in the charged form are included, ie, for example, amino groups in the protonated form and acid groups in the deprotonated form. Counter ions of the charged structural units such as Na, chloride, phosphate, formate, acetate, etc. are not considered. The calculation can be carried out by determining the molar amounts of the structural units of the polymer present at the end of the reaction for an approach starting from the amounts of monomers used, the degree of hydrolysis and, if appropriate, the amount of polymer analog, and using the molar masses of the polymer Structural units are converted into the weight fractions. The sum of the parts by weight gives the total amount of the polymer in this approach. The polymer content without Gegenion results from the ratio of the total amount of polymer to the total mass of the approach. The total content of primary amino groups and / or amidine groups can be carried out analogously to the procedure described above for the polymer content. Starting from the amounts of monomers used, the analytically determined degree of hydrolysis, the ratio of amidine groups to primary amino groups determined by ¹³ C-NMR spectroscopy and optionally the fraction which has been reacted polymer-analogously, the molar composition of the structural units present at the end of the reaction becomes of the polymer determined. With the aid of the molar mass of the individual structural units, the molar proportion of primary amino groups and / or amidine units in meq, which are in 1 g of polymer, can be calculated therefrom. Example H1 250.0 g of the polymer solution obtained according to P1 were mixed in a 500 ml four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser at a stirrer speed of 80 rpm with 6.4 g of a 40 wt .-% aqueous sodium bisulfite solution and then to 80 ° C. heated. Then 147.8 g of a 25% strength by weight aqueous sodium hydroxide solution were added. The mixture was kept at 80 ° C for three hours. The resulting product was cooled to room temperature and adjusted to pH 2.0 with 163.1 g of 37% strength by weight hydrochloric acid. A slightly yellow polymer solution was obtained. The degree of hydrolysis of the vinylformamide units was 70 mol%. Example H2

300.0 g of the polymer solution obtained according to P2 were heated to 80 ° C. in a four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser at a stirrer speed of 80 rpm. Then 157.3 g of a 25 wt .-% aqueous sodium hydroxide solution was added. The mixture was kept at 80 ° C for three hours. The resulting product was cooled to room temperature.

A slightly yellow polymer solution was obtained. The degree of hydrolysis of the vinylformamide units was 100 mol%.

Example H 3

700.0 g of the polymer solution obtained according to P2 were added in a 21 three-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser at a stirrer speed of 80 rpm with 9.8 g of a 40 wt .-% aqueous sodium bisulfite solution and then heated to 80 ° C. , Then 219.3 g of a 25 wt .-% aqueous sodium hydroxide solution was added. The mixture was kept at 80 ° C for three hours. The product obtained was cooled to room temperature and adjusted to pH 7.0 with 102.1 g of 37% strength by weight hydrochloric acid.

A slightly yellow polymer solution was obtained. The degree of hydrolysis of the vinylformamide units was 70 mol%.

Example H 4

400.0 g of the polymer solution obtained after P2 were heated to 80 ° C. in a four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser at a stirrer speed of 80 rpm. Then, 87.4 g of a 25 wt .-% aqueous sodium hydroxide solution was added. The mixture was kept at 80 ° C for three hours. The resulting product was cooled to room temperature and adjusted to pH 7.0 with 39.8 g of 37% strength by weight hydrochloric acid.

A slightly yellow polymer solution was obtained. The degree of hydrolysis of the vinylformamide units was 50 mol%.

Example H 5

136.1 g of the polymer solution obtained according to P2 were mixed in a 500 ml four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser at a stirrer speed of 80 rpm with 1, 9 g of a 40 wt .-% aqueous sodium bisulfite solution and then heated to 80 ° C. Then, 23.8 g of a 25% strength by weight aqueous sodium hydroxide solution were added. ben. The mixture was kept at 80 ° C for 4 hours. The resulting product was cooled to room temperature and adjusted to pH 3.0 with 24.7 g of 37% strength by weight hydrochloric acid. A slightly yellow polymer solution was obtained. The degree of hydrolysis of the vinylformamide units was 40 mol%.

Example H 6

603.3 g of the polymer solution obtained according to P2 were mixed in a four-necked flask with blade stirrer, internal thermometer, dropping funnel and reflux condenser at a stirrer speed of 80 rpm with 8.6 g of a 40% strength by weight aqueous sodium bisulphite solution and then at 80.degree C heated. Then 94.9 g of a 25% aqueous sodium hydroxide solution were added. The mixture was kept at 80 ° C for 4 hours. The resulting product was cooled to RT and adjusted to pH 3.0 with 31.7 g of 37% strength by weight hydrochloric acid.

A slightly yellow polymer solution was obtained. The degree of hydrolysis of the copolymerized vinylformamide units was 35 mol%.

Example H 7

250.0 g of the polymer solution obtained according to P3 were mixed in a 500 ml four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser at a stirrer speed of 80 rpm with 2.3 g of a 40% strength by weight aqueous sodium bisulfite solution and then to 80 ° C heated. Then, 34.7 g of a 25 wt .-% aqueous sodium hydroxide solution was added. The mixture was kept at 80 ° C for three hours. The resulting product was cooled to room temperature and adjusted to pH 3.0 with 31.7 g of 37% strength by weight hydrochloric acid. A slightly yellow polymer solution was obtained. The degree of hydrolysis of the vinylformamide units was 48 mol%.

Example H 8

300.0 g of the polymer solution obtained according to P4 were mixed in a 500 ml four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser at a stirrer speed of 80 rpm with 3.5 g of a 40% strength by weight aqueous sodium bisulphite solution and then to 80 ° C heated. Then, 53.6 g of a 25 wt .-% aqueous sodium hydroxide solution was added. The mixture was kept at 80 ° C for three hours. The resulting product was cooled to room temperature and adjusted to pH 7.5 with 24.1 g of 37% strength by weight hydrochloric acid. A slightly yellow polymer solution was obtained. The degree of hydrolysis of the vinylformamide units was 52 mol%.

Example H 9

1006.0 g of the polymer solution obtained according to P4 were in a 21 four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser at a stirrer speed of 80 rpm with 1 1, added 7 g of a 40 wt .-% aqueous sodium bisulfite solution and then to 80 ° C. heated. Then 395.4 g of a 25 wt .-% aqueous sodium hydroxide solution was added. The mixture was kept at 80 ° C for 7 hours. The resulting product was cooled to room temperature. A slightly yellow polymer solution was obtained. The degree of hydrolysis of the vinylformamide units was 100 mol%.

Example H10

300.0 g of the polymer solution obtained according to P5 were mixed in a 500 ml four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser at a stirrer speed of 80 rpm with 3.3 g of a 40% strength by weight aqueous sodium bisulphite solution and then at 80.degree heated. Then, 120.4 g of a 25 wt .-% aqueous sodium hydroxide solution was added. The mixture was kept at 80 ° C for three hours. The resulting product was cooled to room temperature.

Example H1 1

300.0 g of the polymer solution obtained according to P5 were mixed in a 500 ml four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser at a stirrer speed of 80 rpm with 3.3 g of a 40% strength by weight aqueous sodium bisulphite solution and then at 80.degree heated. Then, 50.2 g of a 25 wt .-% aqueous sodium hydroxide solution was added. The mixture was kept at 80 ° C for three hours. The resulting product was cooled to room temperature and adjusted to pH 7.5 by the addition of 22.6 g of 37% strength by weight hydrochloric acid.

A slightly yellow polymer solution was obtained. The degree of hydrolysis of the vinylformamide units was 52 mol%.

Example H12

600.0 g of the polymer solution obtained according to P6 were mixed in a 21 four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser at a stirrer speed of 80 rpm with 4.5 g of a 40% strength by weight aqueous sodium bisulphite solution and then heated to 80.degree , Then, 150.0 g of a 25% aqueous sodium hydroxide solution was added. The mixture was kept at 80 ° C for 7 hours. The resulting product was cooled to room temperature.

A slightly yellow polymer solution was obtained. The degree of hydrolysis of the vinylformamide units was 100 mol%. Example H13

847.2 g of the polymer solution obtained according to P7 were mixed in a 21 four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser at a stirrer speed of 80 rpm with 9.3 g of a 40 wt .-% aqueous sodium bisulfite solution and then heated to 80 ° C. , Then, 313.7 g of a 25% aqueous sodium hydroxide solution was added. The mixture was kept at 80 ° C for 7 hours. The resulting product was cooled to room temperature and adjusted to pH 8.5 by the addition of 1 17.0 kg of 37% strength by weight hydrochloric acid.

A slightly yellow polymer solution was obtained. The degree of hydrolysis of the vinylformamide units was 100 mol%. Example H14

846.5 of the polymer solution obtained according to PI were in a 21 four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser at a stirrer speed of 80 rpm with

236.3 g of demineralized water and 9.3 g of a 40 wt .-% aqueous sodium bisulfite solution and then heated to 80 ° C. Then, 128.3 g of a 25% aqueous sodium hydroxide solution was added. The mixture was kept at 80 ° C for 5 hours. The resulting product was cooled to room temperature and adjusted to pH 8.3 by the addition of 52.0 kg of 37% strength by weight hydrochloric acid.

Example H15

360.0 g of the polymer solution obtained according to P8 were mixed in a 500 ml four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser at a stirrer speed of 80 rpm with 2.5 g of a 40% strength by weight aqueous sodium bisulfite solution and then at 80 ° C. heated. Then, 41.3 g of 37% hydrochloric acid were added. The mixture was kept at 80 ° C for three hours. The resulting product was cooled to room temperature.

Example H16

638.4 g of the polymer solution obtained according to P8 were in an 11 four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser at a stirrer speed of 80 rpm with 4.7 g of a 40 wt .-% aqueous sodium bisulfite solution and then heated to 80 ° C. Then, 158.3 g of a 25 wt .-% sodium hydroxide solution was added. The mixture was kept at 80 ° C for 6 hours. The resulting product was cooled to room temperature.

Example H17

1224.3 g of the polymer solution obtained according to P8 were mixed in a 21 four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser at a stirrer speed of 80 rpm with 704.4 VU water and 8.9 g of a 40% strength by weight aqueous sodium bisulphite solution and then heated to 80 ° C. Then, 140.4 g of a 25gew .-% sodium hydroxide solution was added. The mixture was kept at 80 ° C for 5 hours. And then cooled to room temperature.

A slightly yellow polymer solution was obtained. The degree of hydrolysis of the vinylformamide units was 50 mol%. Example H18

102.9 g of the polymer solution obtained according to P9 were mixed in a four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser at a stirrer speed of 80 rpm with 10.5 g of a 40% strength by weight aqueous sodium bisulphite solution and then to 80.degree C heated. Then, 355.6 g of a 25 wt .-% sodium hydroxide solution was added. The mixture was kept at 80 ° C for 7 hours and then cooled to room temperature.

A slightly turbid polymer solution was obtained. The degree of hydrolysis of the vinylformamide units was 100 mol%.

Example H19

200.0 g of the polymer solution obtained according to P10 were in a 500 ml four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser at a stirrer speed of 80 rpm with 1, 5 g of a 40 wt .-% aqueous sodium bisulfite solution and then to 80 ° C. heated. Then, 73.4 g of a 25 wt .-% sodium hydroxide solution was added. The mixture was held at 80 ° C for three hours, with the suspension going into solution. The resulting product was cooled to room temperature.

A slightly turbid polymer solution was obtained. The degree of hydrolysis of the vinylformamide units and the vinylacetate units was 100 mol% in both cases.

Example H20

200.0 g of the polymer solution obtained according to P1 1 were mixed in a 500 ml four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser at a stirrer speed of 80 rpm with 1, 3 g of a 40 wt .-% aqueous sodium bisulfite solution and then to 80 ° C heated. Then, 72.0 g of a 25 wt .-% sodium hydroxide solution was added. The mixture was held at 80 ° C for three hours, with the suspension going into solution. The resulting product was cooled to room temperature.

A slightly turbid polymer solution was obtained. The degree of hydrolysis of the vinylformamide units and the vinylacetate units was 100 mol% in both cases. Example H21

200.0 g of the polymer solution obtained according to P12 were in a 500 ml four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser at a stirrer speed of 80 rpm with 1, 1 g of a 40 wt .-% aqueous sodium bisulfite solution and then to 80 ° C. heated. Then, 72.8 g of a 25gew .-% sodium hydroxide solution was added. The mixture was held at 80 ° C for three hours, during which the suspension went into solution. The resulting product was cooled to room temperature.

Example H22

450.0 g of the polymer solution obtained according to P13 were mixed in a 1 l four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser at a stirrer speed of 80 rpm with 450 g of water and 2.8 g of a 40% strength by weight aqueous sodium bisulphite solution and then added 54.6 g of 37% hydrochloric acid. The mixture was heated to boiling and held at reflux for 4 hours. The resulting product was cooled to room temperature.

This gave a yellowish polymer solution having a solids content of 8.6 wt .-%. The degree of hydrolysis of the vinylformamide units was 98 mol%.

Example H23

180.0 g of the polymer solution obtained according to P14 were mixed in a 500 ml four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser at a stirrer speed of 80 rpm with 1.5 g of a 40% strength by weight aqueous sodium bisulphite solution and then heated to reflux. 53.9 g of a 37% strength by weight hydrochloric acid were added and refluxed for 8 hours. The resulting product was cooled to room temperature.

A viscous, slightly cloudy polymer solution having a solids content of 22.5% by weight was obtained. The degree of hydrolysis of the vinylformamide units was 100 mol%.

Example H24

200.0 g of the polymer solution obtained according to P15 were heated to 80 ° C. in a 500 ml four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser at a stirrer speed of 80 rpm. After this temperature was reached, first, 1.4 g of a 25 wt .-% aqueous sodium bisulfite solution and then 44.6 g of a 25 wt .-% aqueous sodium hydroxide solution were added so that they mixed well. The reaction mixture was kept at 80 ° C for 3 hours and then cooled to room temperature. This gave a viscous, slightly yellow polymer solution having a solids content of 22.7 wt .-%. The degree of hydrolysis of vinylformamide units was 99 mole%.

3. Polymer analogue reactions

The polymer-analogous reactions explained in detail below are summarized in Table 3. All polymer-analogous reactions were carried out with the starting polymer H2, which is a fully hydrolyzed homopolymer of vinylformamide (polyvinylamine with a degree of hydrolysis of 100 mol%).

Table 3: Polymer-analogous reactions

¹⁾ QUAB 342 (alkylating agent from SKW, Germany)

² > amount of reagent used [mol%] based on prim. amino groups

3> total content of prim. Amino groups and / or amidine units in 1 g of polymer without counterion

PG: polymer content without counterion

The conversion of the subsequent reactions was determined by determining the residual content of the reagent in the final product. The methods used are given in the examples.

Example PA 1

250 g of the polymer solution obtained after H2 were introduced into a 500 ml four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser. While stirring (stirrer speed 80 rpm), the solution was diluted with 250 g of water and adjusted to a pH of 10 by adding about 17 g of 37% strength by weight hydrochloric acid. At room temperature, 18.9 g of a 50 wt .-% aqueous solution of acrylamide were added dropwise and the resulting solution slowly heated to 70 ° C. The solution was left at 70 ° C. for 6 hours and the adjusted pH was maintained by adding 25% strength by weight sodium hydroxide solution. It was then cooled to room temperature and the pH was adjusted to 8.3 by the addition of 10.2 g of 37% strength by weight hydrochloric acid.

The viscous solution obtained had a residual content of acrylamide of 20 ppm (HPLC) and had a polymer content without Gegenion of 5.4 wt .-%. Example PA 2

850 g of the polymer solution obtained after H2 were introduced into a 1 l four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser. With stirring (stirrer speed 80 rpm), the solution was adjusted to a pH of 9 by adding about 79 g of 37% strength by weight hydrochloric acid. 148.9 g of a 50% strength by weight aqueous acrylamide solution were added dropwise at room temperature and the resulting reaction mixture was slowly heated to 70.degree. The solution was stirred for 6 h at 70 ° C and then cooled to room temperature. The pH was then adjusted to a value of 8.4 by the addition of 3.7 g of 37% strength by weight hydrochloric acid.

The viscous solution obtained had a residual content of acrylamide (HPLC) of 40 ppm and had a polymer content without counterion of 13.3 wt .-%.

Example PA 3

200.0 g of the polymer solution obtained after H2 were placed in a 500 ml four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser. While stirring (stirrer speed 80 rpm), 4.6 g of benzyl chloride were added. The resulting dispersion was heated to 65 ° C and held at this temperature for three hours. This formed a clear, viscous solution with a polymer content without counterion of 8.2 wt .-%. The residual content of benzyl chloride (HPLC) was below the detection limit of 10 ppm.

Example PA 4

200.0 g of the polymer solution obtained after H2 were placed in a 500 ml three-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser. While stirring (stirrer speed 80 rpm), 200 g of water were added first. With 12.6 g of 37% hydrochloric acid, the pH was adjusted to 10 and then add 5.9 g of acrylonitrile. The resulting solution was heated to 75 ° C, held for 5 hours at this temperature and then cooled to room temperature. The resulting viscous solution had a residual content of acrylonitrile (head Space GC) of 130 ppm. The polymer content without Gegenion was 5.3 wt .-%. Example PA 5

200.0 g of the polymer solution obtained after H2 were placed in a 500 ml four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser. While stirring (stirrer speed 80 rpm), 200 g of water were added first. With 12.6 g of 37 wt .-% hydrochloric acid, the pH was adjusted to 10 and then add 1 1, 8 g of acrylonitrile. The resulting solution was heated to 75 ° C, held at this temperature for 5 hours and then cooled to room temperature. The viscous solution obtained had a residual content of acrylonitrile (headspace GC) of 300 ppm. The polymer content without counterion was 6.6 wt .-%. Example PA 6

200.0 g of the polymer solution obtained after H2 were placed in a 500 ml four-necked flask with paddle stirrer, internal thermometer, dropping funnel and reflux condenser. While stirring (stirrer speed 80 rpm) was first added 120 g of water and then 3.2 g of QUAB 342 (3-chloro-2-hydroxypropyl-lauryl-dimethylammoniumchloride, alkylating agent from SKW, Germany) was added. The resulting solution was heated to 66 ° C and held at this temperature for 5 hours. After this reaction time, a complete conversion of the alkylating agent could be detected by means of the Preußmann test. It was then cooled to room temperature. The viscous solution obtained had a polymer content without counterion of 4.5% by weight.

The performance of the Preußmann test is described, for example, in EP 1651699 page 4, line 50 to page 5 line 20. Example SP 1

The polymer used was identical to the Hofmann degradation product designated in WO 2006/0751 15 on page 13 in the table as C8 beta 2. It was prepared by reacting polyacrylamide with sodium hypochlorite in a molar ratio of 1: 1, and sodium hydroxide solution, the molar ratio of sodium hydroxide to sodium hypochlorite being 2: 1.

The polymer content without Gegenion was 4.5% and the content of primary amino groups 9.8 meq / g.

Preparation of the aqueous compositions according to the invention

Examples EF1 to EF44

The procedure was as follows:

250 g of the respective resulting solution of the polymer having primary amino groups and / or amidine groups (see Table 4) were placed in a 500 ml three-necked flask with paddle stirrer, pH electrode and dropping funnel at room temperature. The pH indicated in the table was then adjusted by adding 37% by weight hydrochloric acid or 25% strength by weight sodium hydroxide solution. Subsequently, 1, 4-cyclohexanedione (Aldrich) was added in solid form. The amount of cyclohexanedione used is shown in Table 4. The mixture was stirred for two hours at room temperature, completely dissolving the cyclohexanedione. The solution thus obtained was used for the performance tests. Table 4: Examples of compositions according to the invention

1, 4-CHD ³⁾ PG ⁴⁾

Eg starting polymer pH

[Mol%] [wt%]

EF1 H1 PVFA, K value 45; BG 70% 2.0 15 13.3

EF2 H2 PVFA, K value 90; HG> 95% 1, 0 8 6.2

EF3 H2 PVFA, K value 90; HG> 95% 1, 0 5 6.0

EF4 H3 PVFA, K value 90; HG70% 1, 0 8 8.9

EF5 H4 PVFA, K value 90; HG50% 3.0 2 10.0

EF6 H4 PVFA, K value 90; HG50% 3.0 5 5.5

EF7 H4 PVFA, K value 90; HG50% 3.0 8 9.8

EF8 H5 PVFA, K value 90; HG40% 3.0 8 10.8

EF9 H6 PVFA, K value 90; HG35% 3.0 8 1 1, 1

EF10 H7 PVFA, K value 120; HG50% 3.0 8 8.1

Copo VFA / NaAS = 80/20, K value 90,

EF1 1 H8 3.0 8 12.5

HG 50%

Copo VFA / NaAS = 80/20, K value 90,

EF12 H9 1, 4 5 7.9

HG> 95%

Copo VFA / NaAS = 70/30, K value 55,

EF13 H10 3.0 15 9.9

HG> 95%

Copo VFA / NaAS = 70/30, K value 55,

EF14 H1 1 3.0 15 15.5

HG 52%

Copo VFA / NaAS = 70/30, K value 85,

EF15 H12 3.0 5 1 1, 5

HG> 95%

Copo VFA / NaAS = 70/30, K value 90,

EF16 H13 2.0 2 8.4

HG> 95%

Copo VFA / NaAS = 70/30, K value 90,

EF17 H13 2.0 5 8.4

HG> 95%

Copo VFA / NaAS = 70/30, K value 90,

EF18 H13 2.0 8 8.5

HG> 95%

Copo VFA / NaAS = 70/30, K value 90,

EF19 H14 4 1 10.5

HG 50%

Copo VFA / NaAS = 70/30, K value 90,

EF20 H14 4 2 10.6

HG 50%

Copo VFA / NaAS = 70/30, K value 90,

EF21 H14 4 5 10.7

HG 50%

Copo VFA / NaAS = 70/30, K value 90,

EF22 H14 4 8 1 1, 0

HG 50%

Copo VFA / NaAS = 70/30, K value

EF23 ¹⁾ H15 4 5 10.2

120, BG 50%

Copo VFA / NaAS = 70/30, K value

EF24 H16 2.5 2 5.5

122, HG> 95%

Copo VFA / NaAS = 70/30, K value

EF25 H16 2.5 5 5.6

122, HG> 95% 1, 4-CHD ³⁾ PG ⁴⁾

Eg starting polymer pH

[Mol%] [wt%]

Copo VFA / NaAS = 70/30, K value

EF26 H16 2.5 8 5.7

122, HG> 95%

Copo VFA / NaAS = 70/30, K value

EF27 H17 3 2 6,7

122, HG 50%

Copo VFA / NaAS = 70/30, K value

EF28 H17 3 5 6,7

122, HG 50%

Copo VFA / NaAS = 70/30, K value

EF29 H17 3 8 6.8

122, HG 50%

Copo VFA / NaAS = 60/40, K value 90,

EF30 H18 2.3 5 10.1

HG> 95%

EF31 Copo VFAA / Ac = 70/30, K value 84,

2) H19 1, 0 5 5.4

HG> 95%

EF32 Copo VFAA / Ac = 60/40, K value 74,

2) H20 1, 0 5 5.4

HG> 95%

EF33 Copo VFAA / Ac = 50/50, K value 684,

2) H21 1, 0 5 5.4

HG> 95%

Copo VFA / AN / Na itaconate logo CNRS logo INIST

EF34

1) H22 49.5 / 49.5 / 1, 0, 1, 5 5 5.6

K value 174, HG> 95%

Copo VFA / AN / Na itaconate logo CNRS logo INIST

EF35

1) H22 49.5 / 49.5 / 1, 0, 1, 5 8 5.8

K value 174, HG> 95%

EF36 Copo VFA / Na AS / AN = 50/30/20,

1) H23 1, 5 5 1 1, 9

K value 90, HG> 95%

Copo VFA / DADMAC = 70/30,

EF37 H24 2 5 9.8

K value 80, HG> 95%

EF38 PA1 2 5 9.6

EF39 PA2 2 5 10,1

EF40 PA3 2 5 8.2

EF41 PA4 2 5 4.1

EF42 PA5 2 5 4,2

EF43 PA6 2 5 3.2

EF44 SP1 Hoffmann degradation product 1 5 2.3

HG: degree of hydrolysis

¹⁾ HCI hydrolysis

² ) VAc fully hydrolyzed

³⁾ 1, 4-CHD: Addition amount of 1, 4-cyclohexanedione in mol% based on the total amount of primary amino groups and amidine groups of the polymer

4> PG: polymer content without counterion Application examples

General manufacturing instructions for woodfree papers

A mixture of bleached birch sulphate and bleached pine sulphite was blotted open in a ratio of 70/30 at a solids concentration of 4% in the laboratory pulper until a freeness of 30-35 was reached. The opened fabric an optical brightener (Blankophor.RTM ^® PSG, Bayer AG) and a cationic starch (Hi-Cat ^® 5163 A) were then added. The digestion of the cationic starch was carried out as a 10 wt .-% starch slurry in a jet cooker at 130 ° C and 1 minute residence time. The metered amount of the optical brightener was 0.5% by weight of commercial product, based on the solids content of the paper stock suspension. The dosage of the cationic starch was 0.5 wt .-% of starch, based on the solids content of the pulp suspension. The pH of the substance was in the range between 7 and 8. The milled substance was then diluted by addition of water to a solids concentration of 0.35 wt .-%. In the next step, an aqueous composition of Examples EF1 1 - EF33 and EF36 was added to the paper stock. The amount of addition varied depending on the examples.

Subsequently, in each case 500 ml of the treated stock suspension were mixed with a 15% by weight filler slurry consisting of precipitated calcium carbonate (PCC). Finally, a cationic retention aid (Polymin ^® KE 540, BASF SE) was also added to the paper stock. The dosing amount of the retention agent was in each case 0.01% by weight of polymer (solid), based on the solids content of the entire paper stock suspension.

The paper stock suspensions thus prepared were used to prepare paper sheets on a Rapid Köthen sheet former according to ISO 5269/2 with a sheet weight of 80 g / m ² . The moist paper sheets were then dried for 7 minutes at 90 ° C. By trying different amounts of filler in the mixing of the filler with the treated pulp and a resulting adjustment of the respective amount of slurry, the filler content for each example and in the references to about 25 wt .-% can be adjusted. reference

For comparison, according to the general production instructions for wood-free paper, a paper stock suspension and paper sheets made therefrom without addition of an aqueous composition. The filler content in the reference sheet was also adjusted to 25% by weight.

Examples 1 -24

The aqueous compositions of the examples EF1 1 -EF33 and EF 36 according to the invention were used to produce paper sheets according to the production instructions for wood-free papers. The addition amount of the aqueous composition was 0.12% by weight of polymer having primary amino groups and / or amidine groups (solid) based on pulp (solid). Comparative Example 1 (Vbsp. 1)

According to the general preparation procedure for wood-free papers, paper sheets were prepared using instead of the aqueous composition according to the invention a 7 wt .-% aqueous solution of H17 (70/30 VFA / NaAS copolymer having a degree of hydrolysis of 50 and a K value of the unhydrolysed polymer of 122) was used. The addition amount of the aqueous composition was 0.12% by weight of polymer having primary amino groups and / or amidine groups (solid) based on pulp (solid).

Examples 25 - 48

The aqueous compositions of the examples EF1 1 -EF33 and EF 36 according to the invention were used to produce paper sheets according to the production instructions for wood-free papers. Incidentally, the addition amount of the aqueous composition was 0.24% by weight of polymer having primary amino groups and / or amidine groups (solid) based on pulp (solid). Comparative Example 2 (Vbsp. 2)

Papers were prepared according to the general preparation procedure for wood-free papers, using instead of the aqueous composition according to the invention a 7% strength by weight aqueous solution of H 17 (70/30 VFA / NaAS copolymer having a degree of hydrolysis of 50 and a K value of the unhydrolyzed polymer from 122). The amount of addition of the aqueous composition was 0.24% by weight of polymer of primary amino groups and / or amidine groups (solid) based on pulp (solid).

Testing the woodfree paper sheets

After a storage time in a climate chamber at a constant 23 ° C and 50% humidity for 12 hours, the dry breaking length of the sheets were determined according to DIN 54540, the internal strength according to DIN 54516 and the flexural strength according to DIN 53121. The results are shown in Table 5 (0.12% added) and in Table 6 (0.24% added).

Table 5: Testing of the woodfree paper sheets with an addition amount of the aqueous composition of 0.12% by weight of polymer having primary amino groups and / or amidine groups (solid) based on pulp (solid).

Ex. Aqueous filler content Dry cracking Internal bendingCompound. [%] length rigidity

[m] [N] [mN]

Reference - 24.5 3614 127 47.2

Vbsp. 1 - 24.5 4481 195.78

1 EF1 1 24.9 4698 232 59.1

2 EF12 25.1 4892 245 65.2

3 EF13 25.5 4256 188 56.9

4 EF14 24.8 4434 202 56.4

5 EF15 25.5 5187 288 69.2

6 EF16 24.9 4998 274 66.5

7 EF17 25.3 4912 281 67.3 Ex. Aqueous filler content Dry cracking Internal bending joint. [%] length strength rigidity

[m] [N] [mN]

8 EF18 24.7 4745 264 63.7

9 EF19 25.4 4691 231 59.3

10 EF20 25.3 4812 256 58.2

1 1 EF21 24.8 4790 261 60.1

12 EF22 25.1 4412 239 55.7

13 EF23 24.8 4789 258 56.9

14 EF24 24.7 5378 306 71, 4

15 EF25 25.4 551 1 339 70.1

16 EF26 25.1 5088 299 68.6

17 EF27 25.3 5290 31 1 72.3

18 EF28 25.5 5589 341 74.9

19 EF29 24.9 5134 302 68.4

20 EF30 24.5 4734 265 62.9

21 EF31 24.8 491 1 287 65.3

22 EF32 24.7 4845 288 67.1

23 EF33 25.3 4723 276 65.9

24 EF36 25.0 4845 267 74.3

It can be seen from the performance data that in each case the use of the composition EF27, EF28 or EF29 according to the invention, which contains the polymer H17 and 1,4-cyclohexanedione (Examples 17, 18 and 19), leads to markedly increased strengths of the papers Compared to papers which were produced only by using the polymer H17 (Vbsp. 1).

Table 6: Testing of the woodfree paper sheets with an addition amount of the aqueous composition of 0.24% by weight of polymer having primary amino groups and / or amidine groups (solid) based on pulp (solid).

Ex. Aqueous filler content Dry cracking Internal bending

Composition. [% By weight] Length Strength Stiffness

[m] [N] [mN]

Reference - 25.1 3614 127 47.2

Vbsp. 2 25.3 4255 161 54.1

25 EF1 1 24.7 4378 188 55.4

26 EF12 25.4 4456 185 56.9

27 EF13 25.1 4199 164 57.4

28 EF14 25.2 4244 178 52.5

29 EF15 25.4 4819 212 59.6

30 EF16 24.6 4765 204 56.8

31 EF17 24.8 4734 209 58.4 Ex. Aqueous filler content Dry cracking Internal bending joint. [% By weight] Length Strength Stiffness

[m] [N] [mN]

32 EF18 24.8 4512 194 58.9

33 EF19 25.2 4434 181 55.8

34 EF20 25.0 4687 193 56.6

35 EF21 25.3 4538 206 58.6

36 EF22 24.6 4227 189 53.2

37 EF23 24,7 451 1 21 1 54,4

38 EF24 25.1 5017 234 64.2

39 EF25 25.3 4945 241 63.2

40 EF26 24.5 4845 229 61, 9

41 EF27 25.4 5023 214 68.2

42 EF28 25.3 5123 281 69.9

43 EF29 24.7 4840 254 65.6

44 EF30 24.5 4478 223 58.9

45 EF31 24,6 441 1 221 61, 7

46 EF32 24.9 4528 218 63.7

47 EF33 25.1 4498 244 62.9

48 EF36 25.2 4634 217 69.6

It can be seen from the performance data that in each case the use of the composition EF27, EF28 and EF29 according to the invention, which contains the polymer H17 and 1,4-cyclohexanedione (Examples 41, 42 and 43), leads to markedly increased strengths of the papers to papers which were prepared only by using the polymer H17 (Vbsp. 2).

General Production Instructions for Testliner Example A1 to A44 Further compounds used as auxiliaries:

Retention agent: Percol 540 (polyacrylamide emulsion having a solids content of 43% of a cationic charge density of 1.7 mmol / 100 g and a K value of 240). Pretreatment of the pulp:

A stock of 100% waste paper (mixture of grades: 1.02, 1 .04, 4.01) was pitched with drinking water at a consistency of 4 wt .-% in a pulper speck-free and ground in a refiner to a freeness of 40 ° SR. This substance was then diluted with drinking water to a consistency of 0.8% by weight.

The pulp yielded a Shopper Riegler value of SR 40 in the dewatering test. The thus-pretreated paper stock based on waste paper was added with stirring in each case to the inventive compositions of Examples EF1-Fe44 given in Table 7. In this case, the addition amount of the aqueous composition was selected such that 0.3 wt .-% polymer with primary amino groups and / or amidine (solid) based on recycled paper pulp (solid) was used.

Subsequently, the retention agent (Percol 540) in the form of a 1 wt .-% aqueous solution was metered to the pulp, with 0.04 wt .-% polymer (solid) based on recycled paper pulp (solid) were used. The pH of the stock was kept constant at pH 7 (using 5% by weight sulfuric acid).

Subsequently, base papers were produced by means of a dynamic sheet former from Tech Pap, France. The paper was then dried with contact dryers to a paper moisture content of 5% by weight.

Reference (not according to the invention)

As a reference, according to the general production instructions for testliner, a paper stock suspension and paper sheets thereof were produced without the addition of an aqueous composition according to the invention.

Comparative Example A1 (not according to the invention)

For comparison, according to the general production instructions for testliner, a paper stock suspension and paper sheets were produced therefrom, the polymer H4 being used instead of the composition according to the invention.

In this case, the addition amount of the polymer H4 was selected such that 0.3 wt .-% polymer with primary amino groups (solid) based on waste paper pulp (solid) was used.

drainage test

In the examples, in each case 1 liter of the paper stock described above was used and in each case successively mixed with the aqueous composition given in the table with stirring and then dewatered using a Schopper-Riegler dewatering tester, wherein the time in seconds for a flow rate (Filtrate) of 600 ml. The concentration of the polymer having primary amino groups and / or amidine groups (solid) was in each case 1% by weight. The measurement results are given in the table.

The papers summarized below in Table 7 were prepared.

Technical application testing of raw papers

Before testing the paper, it was stored for 24 hours at 50% humidity and the following strength tests were carried out Bursting pressure according to DIN ISO 2758 (up to 600 kPa) and DIN ISO 2759 (above 600 kPa) SCT according to DIN 54518 (Shortspan compression test, determination of the strip crush resistance)

CMT according to DIN EN 23035 (Corona medium test, determination of flat crush resistance)

As can be seen from the results in Table 7, the use of the aqueous compositions according to the invention comprising polymers having primary amino groups and / or amidine groups and 1,4-cyclohexanedione makes it possible to significantly increase the paper strengths.

Table 7: Technical results

¹⁾ Amount of the polymer having primary amino groups and / or amidine groups (solid) which has been used in the form of the aqueous composition according to the invention.

The% value for CMT, SCT and Burst represents the increase in% compared to the reference.

It can be seen from the performance data that in each case the use of the composition EF5, EF6 or EF7 according to the invention, which contain the polymer H4 and 1,4-cyclohexanedione (Ex. A5, A6 and A7), leads to markedly increased strength of the papers Comparison to paper, which were produced only by using the polymer H4 (Vbsp. A1).

Claims

claims

Containing aqueous composition

(a) a polymer having primary amino groups and / or amidine groups with a total content of these groups of> 1, 5 meq / g of polymer and

(B) 0.01 to 50 mol% of 1, 4-cyclohexanedione (b) based on the total amount of primary amino groups and amidine groups of the polymer, wherein the aqueous composition has a pH <6.

Aqueous composition according to claim 1, characterized in that it contains ≥ 50% by weight of water, based on the aqueous composition.

Aqueous composition according to claim 1 or 2, characterized in that it has a pH in the range of 2 to 6.

Aqueous composition according to any one of claims 1 to 3, characterized in that the polymer having primary amino groups and / or amidine groups is selected from hydrolyzed homopolymers of N-vinylcarboxamide, hydrolyzed copolymers of N-vinylcarboxamide and other neutral monoethylenically unsaturated monomers, hydrolyzed copolymers of N -Vinylcarboxamide and anionic monoethylenically unsaturated monomers, hydrolyzed copolymers of N-vinylcarboxamide and cationic monoethylenically unsaturated monomers, hydrolyzed homopolymers of N-vinylcarboxamide, which have been reacted polymer-analogously, Hofmann degradation products of homopolymers or copolymers of

(Meth) acrylamide and ethyleneimine units containing polymers.

Aqueous composition according to any one of claims 1 to 4, characterized in that the polymer having primary amino groups and / or amidine groups is selected from hydrolyzed copolymers of N-vinylcarboxamide and other neutral monoethylenically unsaturated monomers, hydrolyzed copolymers of N-vinylcarboxamide and anionic monoethylenically unsaturated monomers , hydrolyzed copolymers of N-vinylcarboxylic acid amide and cationic monoethylenically unsaturated monomers, and their degree of hydrolysis is 10 10 mol%.

Aqueous composition according to any one of claims 1 to 5, characterized in that the polymer having primary amino groups and / or amidine groups is a partially and fully hydrolyzed copolymer obtainable by polymerizing

30-99 mol% of at least one monomer of the formula in which R ^{1 is} H or C ¹ to C 6 alkyl,

0 - 70 mol% of one or more other neutral monoethylenically unsaturated

Monomers (iia),

0-70 mol% of one or more monomers (abb) selected from monoethylenically unsaturated sulfonic acids, monoethylenically unsaturated phosphonic acids, monounsaturated esters of phosphoric acid, monoethylenically unsaturated carboxylic acids having 3 to 8 carbon atoms in the molecule and / or their alkali metal, alkaline earth metal or ammonium salts,

optionally compounds which have at least two ethylenically unsaturated double bonds in the molecule, with the proviso that the sum of the proportions of the monomers (iia), (trans) and (iic) is in total 1 to 70 mol%,

and subsequent partial or complete hydrolysis of the copolymerized in the polymer units of the monomers (I) to form amino groups.

Aqueous composition according to any one of claims 1 to 6, characterized in that the polymer having primary amino groups and / or amidine groups is a partially or fully hydrolyzed copolymers of N-vinylcarboxamide with other neutral, anionic and / or cationic monoethylenically unsaturated monomers, wherein said monomer is selected acrylonitrile, vinyl acetate, sodium acrylate, diallyldimethylammonium chloride, [3- (dimethylamino) propyl] acrylamide, N- [3- (dimethylamino) propyl] methacrylamide, [3- (trimethylammonium) propyl] acrylamido chloride and N- [3- ( Trimethyl ammonium) propyl] methacrylamide chloride.

Aqueous composition according to any one of claims 1 to 7, characterized in that the polymer having primary amino groups and / or amidine groups is a partially or fully hydrolyzed copolymers of N-vinylcarboxamide with sodium acrylate, and a degree of hydrolysis> 30 mol%.

Aqueous composition according to any one of claims 1 to 4, characterized in that the polymer having primary amino groups and / or amidine groups is a partial or fully hydrolyzed homopolymer of N-vinylcarboxamide and a degree of hydrolysis> 30 mol%.

10. An aqueous composition according to any one of claims 1 to 9, characterized in that the aqueous composition

(A) 5 to 40 wt .-% based on the aqueous composition of a polymer having primary amino groups and / or amidine groups with a total content of these groups of> 1, 5 meq / g of polymer and

(B) 0.1 to 30 mol% of 1, 4-cyclohexanedione (b) based on the total amount of primary amino groups and / or amidine groups of the polymers.

1 1. Use of the aqueous composition according to any one of claims 1 to 10 as a solidifying agent in the process of making paper and board by increasing the pH by at least one step.

12. A process for the production of paper or board comprising the addition of an aqueous composition according to any one of claims 1 to 10 to a paper stock having a pH in the range of 6 to 8 and then dewatering of the paper stock below

Sheet formation and drying.

13. The method according to claim 1 1, characterized in that the aqueous composition is added in an amount of 0.01 to 6 wt .-% of the polymer having primary amino groups and / or amidine groups, based on pulp.

14. The method according to claim 13, characterized in that waste paper is used as pulp. 15. The method according to claim 13 or 14, characterized in that 20 to 30 wt .-% filler based on the paper is used.

16. paper or board prepared according to a method of claims 12 to 15.