DE2146511A1 - Wet strength resins, process for their preparation and use - Google Patents

Description

Dr. Hans-Heinrich Willrath d - 52 Wiesbaden 1 h . sept .

Dr. Dieter Weber Postf _a * i327 v / _P f

Gustav Freytag Strafe Ϊ5

Dipl.-Phys. Klaus Seiffert 2 1 Λ 6 51 1 * ^{mm 37i720}

^{r J} t Itvyl II telegram address: WILLPATENT

PATENT LAWYERS
Docket_70-3 * l

ROHMANDHAAS COMPANY Independence Mall West Philadelphia, PA 19105

WET STRENGTH RESINS, PROCESS FOR THEIR PRODUCTION

AND USE

Priority Date Sept. 22, 1970 in USA, Ser.No.7 ^ 99

U.S. Patent 3,288,770 describes the preparation water-soluble polymers containing quaternary ammonium and allegedly capable of increasing the wet strength of Improve paper by adding certain quaternary ammonium chloride salt monomers, such as those in general, to water formula

H ₂ C = C (R) -CH ₂ A

.Cl N ⁺ "(I) H ₂ C = C (R ') - CH ₂ B

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Postal check: f-rankfutt / M «ln 6763 Bank: Dresdner Bank AG, Wiesbaden, account no. 276 B07

-Z-

dissolves, in which A and B independently of one another are alkyl, Hydroxyalkyl or phenyl radicals which have amido, carbon-lower alkoxy, lower alkoxy, mono- and dicyloxy, cyano, thio-lower alkoxy, thiophenoxy or lower alkoxy groups (the one Form keto group), 5- and 6-membered cycloalkyl groups and only a nitro group and alkyl groups only in Phenylreet can contain a halogen atom (chlorine, bromine, fluorine and iodine).

The symbols R and R * mean independently of one another Hydrogen atoms, chlorine atoms, bromine atoms or low molecular weight alkyl groups or phenyl radicals with substituents as defined above for A and B.

A catalytic amount of a free radical generating polymerization catalyst is also included in the Solution given, or it may already be in it The polymerization catalyst is preferably a peroxide catalyst such as tert-butyl peroxide, but can also others are used.

The resulting solution is maintained at a temperature between 0 ° C and 100 ⁰ C for about 1 to 72 hours, depending on the temperature. The solid polymer can then be isolated from the reaction mixture and is essentially a linear homopolymeric molecular chain of repeating units of the formula

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2H6511

(II)

According to the present invention, new polymers are obtained by polymerizing a tertiary diallylamine of the general formula

H ₂ C = C (R) -CK,

(in)

wherein R is a hydrogen atom or a methyl group, R ^{1 is} a hydrogen atom or a methyl group, and R ° is an alkyl group having 1-8 carbon atoms, an aryl group having 6-8 carbon atoms or a hydroxyalkyl group

man

with 1-8 carbon atoms means whereon the polymer with an epihalohydrin of the general formula

(IV)

quaternized, where Y is a halogen, such as chlorine, fluorine, Is bromine or iodine.

o-CH - CH ₀

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That before the quaternization with the epihalohydrin obtained polymer has units of the following formula in the form of salts thereof with an acid, like hydrochloric acid ι

R ⁰
Alternatively, the amine monomer is first quaternized with an epihalohydrin to give a monomer of the formula.

H ₂ C »C (R ') - CH ₂ CH ₂ -CH-OH or

/ \ · ^Χ "(VII) H ₂ C = C (R ') - CH ₂ CH ₂ CH (OH) -

where R, R ¹ , R ° and Y are as defined above and X ** is an anion such as F ~, Cl ", Br", l " , OH", RCOO ", SOjl ⁼ ,,

NO ₃ , ClO ^, PO ^ -, or RSO ₃ , and R is a phenyl radical

or means a low molecular weight alkyl group with 1-4 carbon atoms. This « monomer is then polymerized.

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The quaternary polymer obtained has units one or both of the following forms

_(A)

R °

CH

• "CH ₂ - CR R

where R, R 'and R have the above meaning, Y is a halogen atom and X "is an anion such as P", Cl ", Br", I ", CH", RCOO ", SO ^ *, NO ₃ ", ClO ^ "P0 ^S or RSO" means wherein R is a Phenylreat or a low molecular weight alkyl group having '1 - k is atoms coals "t off * Each · .the first four-mentioned anions can verwende- of in the quaternization by appropriate selection' , ■ ' th epihalohydrins are obtained. Addition of an • inorganic base, such as sodium hydroxide, to the quaternized polymer delivers the OH ** anion and converts the

Units convert to (A) form when the pH is 8-9

J ■ " ⁶ "

6AD ORIGINAL

achieved. The (B) form occurs at pH values below 8 and is almost exclusively present when the pH is 5 or less. Other anions can be obtained by merely adding the appropriate acid to the base form of (a), which addition ultimately converts essentially all units of the (B) form with the relevant anion of the added acid. During storage, it is preferred that these inputs ψ units of the polymer to a large extent or have substantially the total Fora (b). Immediately prior to use, particularly when used for the wetting of paper, these units are largely or essentially converted into the (A) form by the addition of inorganic bases such as alkali hydroxide.

These monomers of the formula III can also be mixed with one or more other monoethylenically unsaturated monomers. be polymerized with a group of the formula HgCeC <^ ml, such as with vinyl esters of aliphatic Cj-Cja acids, such as vinyl acetate, vinyl laurate and vinyl stearate, esters of acrylic acid or methacrylic acid with Cj-Cg alcohols including the C 1 _{-C 18 alkenols} , Benzyl alcohol, cyclohexyl alcohol and isobornyl alcohol, such as methyl acrylate or methacrylate, ethyl acrylate or methacrylate, butyl acrylate or methacrylate, 2-ethylhexyl acrylate or methacrylate, octadecyl acrylate or methacrylate, vinyl aromatic hydrocarbons,

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such as styrene, isopropenyltoluene and various dialkylstyrenes, acrylonitrile, methacrylonitrile, ethacrylonitrile and phenylacrylonitrile, acrylamides, methaorylamides, ethacrylamides, N-methylolacrylamides, N-monoalkyl and N-dialkyl acrylamides, N-dialkyl acrylamides and N-methacrylamides, such as -methacrylamides, propyl, butyl and N-dimethyl, ethyl, propyl, butyl acrylamides, alkacrylamides such as N-monophenyl and N-diphenyl acrylamides and methacrylamides, vinyl ethers such as butyl vinyl ethers, N-vinyl lactarns such as N-vinylpyrrolidone, and olefins, such as ethylene, fluorinated vinyl compounds, such as vinylidene fluoride, ß-hydroxyethyl aorylate or methacrylate or any hydro jyl-containing or amine-containing monomers mentioned in column 2 or 3 of US Pat. No. 3,150,112, vinyl chloride and vinylidene chloride, Alkyl vinyl ketones, such as methyl vinyl ketone, ethyl vinyl ketone and methyl isopropenyl ketone, itaconic acid diesters which contain a single CHeC C ^ group, such as dimethyl, diethyl, dipro pyl, dibutyl and other saturated aliphatic diesters of itaconic acid with a monohydric alcohol, diphenylitaconate, di (p> henylethyl) itaconate, allyl and methallyl ethers of saturated aliphatic monocarboxylic acids, such as allyl propionate and methallyl acetate, allyl acetate and allyl acetate and methallyl valerates, vinylthiophene, h- vinylpyridine, vinylpyrrole and acids such as acrylic acid, methacrylic acid, itaconic acid and <X-methylene_glutaric acid.

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The Waaserlöslichkelt can be guaranteed by one either the amount of or the mixed monomiesis of limited hydrophobic character or one or more hydrophilic monomers as part or as a total amount of the mixed monomers rgehaite8 adds For example, mixed polymers, which is as little as 10 Mo1- $ units of the Formula V, become water-soluble or easily dispersible in water when quaternized if the

r other units of the copolymer are only moderately hydrophobic, such as methyl methacrylate, ethyl acrylate or methyl acrylate or mixtures thereof. If the more hydrophobic mixed monomers are used, such as butyl acrylate or methacrylate, 2-ethylhexyl acrylate or methacrylate, acrylonitrile, styrene, vinyl toluene, vinyl chloride and vinylidene chloride or mixtures thereof, the smallest amount of the units of the formula V that is required to when quaternized, the water solubility mn is 13-20 mol ~ $

k. By incorporating at least about one MoI- ^ hydrophilic monomers, such as an acid, for example acrylic acid, methacrylic acid or itakonaäiare, or an amide (such as acrylamide, methacrylamide, H-methyl © laeryl <»amide or N-methylacrylamide), β-hydroxyethyl acrylate and β-ureido ethyl acrylate, one can accordingly undertake a moderate or less strong reduction in the amount of the units of the formula V and still retain the water in the finally quaterniextea P ο lysis r-. This rule also applies in general to the quaternized polymers, which are

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nized monomers of the formulas VX and VIX.

The polymerization of the monomer of formula III cd he the quaternary compound thereof with epichlorohydrin can

ο ο at a temperature of 0 C to 100 C, preferably im

Range of 50-80 C, be carried out in an aqueous medium containing about 0.1-3 wt .- ^, based on the monomer weight, of an initiator with free radicals, such as a peroxy catalyst, for example tert-butyl hydroperoxide, hydrogen peroxide or a Ammonium or alkali metal persulfate. They can be used together with sodium hydrogen sulfite or other reducing agents in redox systems. Instead, the polymerization can also be brought about by irradiation. If homopolymers are desired, an emulsifier is unnecessary since the monomer of Formula III is generally soluble either as a base * or as its salt, such as its hydrochloride. If mixed polymers are prepared from a mixture of a monomer of the formula III with water-insoluble mixed monomers, an emulsifier (of the nonionic or cationic type) for the latter in an amount of 0.1-6 wt .- ^, preferably from 0.5 to k wt .- ^, based on the weight of the water-insoluble monomers to be emulsified. As emulators, tert-octyl or tert-nonylphenoxypolyethoxyethanols with about 10 - 50 or more oxyethylene groups, octadecylamine sulfate, cyclohexyl diethyl (dodecyj) amine sulfate, octadecyltrimethylamraonumbroraid,

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Polyethoxyamines or mixtures of 2 or more such emulsifiers are used.

The quaternization of the monomer of formula III or one Polymer thereof can be in an aqueous medium containing the hydrochloric acid salt of the monomer or the polymer contains under acidic conditions (pH 6 or less) by adding an epihalohydrine of the above formula IV will.

The reaction can be carried out at room temperature to about 80 ° C. In general, the process should be controlled in such a way that a temperature exceeding about 80 ° C. is avoided, temperatures above 50 ° C. being preferably avoided. The reaction is most conveniently carried out in aqueous media, preferably in water itself. The starting salts and the epihalohydrin are sufficiently water-soluble to make water completely suitable as a reaction medium. The epihalohydrin is preferably used in a stoichiometric amount or in an excess thereof. The aqueous medium can contain a water-miscible cosolvent when R is an alkyl group with k or more carbon atoms. No catalyst is required for the reaction. However, it is essential that the pH is kept on the acidic side during the reaction in order to prevent undesired side reactions. The response is quick, even when working at room temperature. Your termination

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can be easily determined by looking at the instillation of Aeintiter followed because the amine group is quaternized. In general, epihalohydrin is added to of the aqueous starting salt solution at such a rapid rate as the temperature control in allowed to the reaction system.

A polymerization inhibitor can be present in the reaction medium when the monomer is alkylated. Examples of inhibitors are such as monomethyl ethers of hydroquinone, hydroquinone and phenothiazine. The amount of inhibitor can be from 0.01 f> to 1 j> , depending on the weight of the Auegange salt

The monomers of the formulas VI and VII quaternized with epihalohydrin can be used directly for copolymerization with acrylonitrile in order to modify its antistatic, color and moisture-restoring properties. The resulting mixed polymer, which contains 0.2 to 1 % by weight of the quaternary Asiiiou ium compound according to the present invention, can also be deformed fibers or threads which can be easily processed into textile yarns and fabrics which show a reduced tendency to generate static charges Develop frictional contact, are more dyeable, especially with acidic dyes, and feel better due to increased moisture absorption or re-uptake. Instead of the quaiernized

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BATH ORIGINAL

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Monomer according to the invention directly with the acrylonitrile to form the main component of fibers or films to copolymerize, a homopolymer or copolymer of the quaternized monomer of the formula VX or VII with one or more other monomers, such as vinyl acetate, ethyl acrylate, styrene or vinyl benzene sulfonate be blended in a relatively small amount with the acrylonitrile polymer, which is the main component ^ which then forms fibers or films to be formed from the mixture.

A quaternized compound of formula VI or VXI can be used for sizing paper. A small amount in the range of 0.2-5% by weight or more of the compound, based on dry fiber weight, may be admixed into the paper pulp in the hollander, or before or after the paper pulp leaves the hollander. A polymerization initiator can be added simultaneously or shortly before or shortly after the addition of the monomer to the pulp. The effect achieved in the dry paper obtained therefrom varies depending on the pH of the system pH is less than 7, the obtained © paper shows a sizing effect, if the pulp is neutral or alkaline or is rendered alkaline _s such as at a pH ~ W © rt from 8 to 10, can also be obtained at any point of the Drying of the archwire formed ine obtained dimensional stability.

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2U6511

In any case, an aqueous dispersion can also be added to the pulp Neutral or acidic polymers can be added, such as poly- (lfchyl acrylate), which is obtained by emulsion polymerization had received. In such a case, the quaternized monomer of formula VI or VII or a serves polymer formed therefrom in situ to anchor the further polymer on the fibers. Instead of one Additional polymer can also be an aqueous dispersion of a wax, such as polyethylene, a pigment or Mineral filler or a material such as one modified with a long chain alcohol Urine to ff formaldehyde resin, which is used in the following Calendering of the paper serves as a transparency maker, can be added.

The reaction of the amine salt polymer (whether homopolymer or Mixed polymer) with the epihalohydrin provides a polymer with units containing the quaternary ammonium groups Formula (a) and (b) included. The relative amounts of (a) and (b) vary depending on the exact reaction conditions, but in a typical case they are present in approximately equivalent amounts. Lowering the pH value apparently reduces the proportion of (a). At pH values of 6 or less, the tendency to gel, attributed to the glycidyl group of (a) iet, inhibited, while with increasing pH up to neutral or alkaline conditions the mixed poly-

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^ H 2U6511

mer to an insoluble state even at room temperature hardens quickly, the higher the pH and the concentration of the polymer, the faster the hardening process is. Apparently groups (B) are converted into groups (a) when the pH is made alkaline, and the alkali-catalyzed conversion of the glyeidyl groups can cause curing and insolubilization of the polymer.

If, however, the polymers according to the present invention, which contain the group (β), are diluted to very low solids contents (2 - 10 * β>) at 5 - 50 ° C. in water, then the pH value can be reduced to 9 without gelation -12 can be increased. The polymer thus obtained is stable for a limited period of time at low solids contents (2-10 ^), although such a polymer cannot be stored indefinitely without gelation or loss of functionality Activated for 1-5 hours, they are two to three times more effective than wet strength resins than they would be with known activation.Dless's alkaline activation process is of particular importance because polymers treated in this way have particular value as wet strength resins for Have paper when the paper is hardened at a pH value of 6 - 10. Although the alkaline activation process for the Poljoerhe rs plate is because of the

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ΖΗ65Ί1

above mentioned stability problems and the required low solids levels (2-10 $) is not practical, it can be convenient for the polymer user, such as in a paper mill.

These properties of the polymers containing groups (b) with or without a monominal content of groups (a) enable the polymer manufacturer to produce very stable polymer compositions, such as latices thereof, to store them and to deliver them to the end user such as the paper maker. Steller, stt transport, of these polymer compositions to any pH conditions, such as at a pH value of 2 - t 5 * "ü ^r simple gluing or at a pH ¥ ert of 7 t> is ^{1 1} or higher for curing of the polymer in paper to develop high wet strength.

Homopolymers or copolymers containing at least 10 mole percent of units (a) or (b) or a weight thereof are generally water soluble to the extent of at least 1% by weight at room temperature, and in most cases they will dissolve to form aqueous solutions with a content of $ 20 or more, the concentration being greater, the greater the viscosity «,

The homopolymers are generally useful as flocculants, such as in the clarification of water χχηύ aqueous. Suspensions, thus the addition "from about 0 _s 01 - 0 _f 5 wt. 56,

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BATH ORIGINAL

2 U 6 5 1 1

based on the weight of suspended solids, of a homopolymer containing units (a) or (b) municipal wastewater to flocculate the suspended matter and remove it by filtration or settling and to facilitate decanting · The homopolymers ^ are thus useful for flocculating aqueous suspensions of any kind and especially for domestic and industrial sewage neutral, clean or alka-P lic character. As mentioned above, they can be used to glue paper and as an anchor for others Layering agents are used, which are applied in aqueous dispersions or suspensions. they are also effective in making mineral fillers provided papers, the retention of which must be avoided.

she
prop up by anchoring the fillers on the

Improve fibers and clarify the white water obtained. The effect of gluing and flocculating ^ is general for all pH values of the systems to which they are applied.

The treatment of paper pulp with the homopolymers (especially after alkaline activation) under neutral or alkaline conditions, if necessary with preceding or subsequent stirring, provides a remarkable Increase in wet strength. The amount of polymer used for this purpose can range from 0.05 to 7 Wt .- ^ or more, based on the dry weight of the Fibers in the pulp, lying with the wet strength with

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BATH ORIGINAL

<γγ 2U6511

the increase in the proportion increases up to about h - 5 $, after which the wet strength remains the same and the glue effect increases.

The water-soluble copolymers which contain 10 mol $ or more of units of the formula (a), regardless of whether units of the formula (b) are also present or not, and also those whose units consist essentially of (a) and (b) are useful for the same purposes as mentioned above for the homopolymers. For use as wet strength resin for paper, the copolymers preferably contain about 35 to 100 units of the formula (a) and units of the formula (b), and optimally these resins are subjected to the alkaline activation process at a solids content of 2-10 ° immediately prior to use.

Copolymers containing 0.25-25 percent by weight or more of units of the formula (b) are useful for many purposes. For example, skid copolymers of acrylonitrile with 0.25-5 Ί ° units of the formula (Β) are particularly useful for the production of fibers and films with improved dyeability, greater resistance to the formation of electrostatic charges through frictional contact and better feel due to greater moisture adsorption. Copolymers containing about 0.5 to 30 $ or more units of the formula (b) with an ester of acrylic acid or of methacrylic acid, such as ethyl

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2 U 6 5 1

acrylate, butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate with or without styrene or vinyl toluene, are quite satisfactory for stabilizing woolen fabrics against shrinkage during washing, for binding non-woven fabrics, for finishing leather, as a binding agent for pigmented compositions, for pigment coloring of textiles, for the production of mineral-coated papers and for lithographic Far-P ben, for gluing paper and as thermosetting coatings for metals, wood, plastics, glass, masonry of all Types, plaster walls and the like.

To assist those skilled in the art in practicing the present invention, the following procedures are presented proposed by way of illustration, with parts and percentages by weight parts and percentages by weight be and the Temperatures are given in C unless otherwise stated.

i) a) A pressure vessel is charged with 50 g (O _t h5h mol) methyldiallylamine and k "} g (O _s kh mol) of concentrated hydrochloric acid charged. To this solution, 1 g tert-butyl hydroperoxide was added. The solution is purified, the vessel tightly closed and heated for 96 hours to 60 ° C. At the end of this time, part of the solution, when titrated with an aqueous standard base, produces a neutralization curve, the center point (pK) of which drops at pH 8.6.

3.

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BAD OfHGINAL

2U651

■ eres diallylmethylarainhydrochlorid has its midpoint (pK _Q ) at pH 10.8. Therefore all of the Amiijpolymer is present.

b) The polymer solution (10 g) is diluted with 200 g of deionized water and 5f6 epichlorohydrin is added. At the end of 7 days at 25 C, an amine titration confirms the absence of titratable AaIn and thus complete quaternization. The pH is adjusted to 2 with concentrated HCl to get a finished resin solution of 6.6 % solids.

2) The resin obtained in i) b) is "activated" by treating 76 g of the resin solution with 10 g of a five percent aqueous sodium hydroxide solution and 14 g of deionized water. This resin solution, which now contains 5 ° solids, is left to stand for five hours. 15 ° g of deionized water are then added in order to lower the solids content to 2 ia. 5 ml of this two percent resin solution are mixed with 2 liters of a one percent slurry of light hardwood-softwood kraft pulp (5Ο / 5Ο, 0.5 solids). The pulp is stirred at pH 7.9 to 36Ο CSF (Canadian Standard Freeness). The pulp is then processed into a sheet with a final consistency of O _t o4 * jL. the

Elbows are then made for 2 minutes at 93 ° C.

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2'651 '

2 dry. The basis weight of the sheets is 62 g per m. The wet strength in kg / cm is determined in a Scott IP tester after immersion in water from Zh C for one hour. A commercially available wet-strength resin, a polyamide resin which has been modified with epichlorohydrin, according to US Pat. No. 2 9-26 116, is used in the same way in various levels and tested for comparison purposes. The results are compiled in the table below

TABEL

Weight- ^ Resin, 'Moisture Strength (kg / cm) Example calculated on the dry weight of the pulp 1 day 28 days

Resin according to 1b) 0.5 0.57 0.73

trade süb- 0.25 liches resin 0.50 ti 1.00 ti 2.00 η

0.35 0.43 0.46 0.64 0.57 0.80 0.68 0.95

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Claims (1)

Claims 1 · Monomeric compound of the general formula ₂₂ R ° H ₂ C = C (R ') - CH ₂ / ^ CH ₂ -CH-CH ₂ or ^x 2 ^ y ⁿ 2 H ₂ C = C (R) -CH ₂ R ^c H ₂ CC (Rt) -CH / ^X CH ₂ CH (OH) -CH ₂ Y where R is a hydrogen atom or a methyl group, R ^{1 is} an hydrogen atom or methyl group and R is an alkyl group with 1 to 8 carbon atoms, an aryl group with 6-8 carbon atoms or a hydroxyalkyl group with 1 to 8 carbon atoms, Y is a halogen atom and X ~ Means anion. 2, polymer containing units of the general formulas -CHp-C-R (A) R ⁰ CHoCH-CH, / ^CH2 \ -CH ₅ -CR Rt-C- ί ϊ ^{(Β) H} 2 \ / ^li 2 209813/1822 ^u S BAD C «K3tNAt. 2H6511 where R is a hydrogen atom or a methyl group, R ' is a hydrogen atom or a methyl group and R is a An alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 8 carbon atoms, or a hydroxyalkyl group with 1 to 8 carbon atoms, Y is a halogen atom and X ~ is an anion. 3. Polymer according to claim 2, characterized in that it ™ at least 0.25 wt .- $ of the units (a) or (b) or both, and in addition to units of at least one other monoethylenically unsaturated monomer having a group H ₉ C = C <C contains. H. Polymer according to claim 3 »characterized in that it contains at least 10 mol $ of units (a) or (b) or both with up to 9 ° mol $ of units of at least one other monoethylenically unsaturated monomer with one | Contains group HpC = C <C. 5. Polymer according to claim h, characterized in that it contains at least 25 mol $ of the units (a) or (b) or both with up to 75 mol ^ 6 units of at least one other monoethylenically unsaturated monomer with a group H ₂ C = C <contains. 6. A method for the preparation of a monomeric compound according to claim 1, characterized in that one in one - 23 - 209813/1822 2U6511 aqueous medium at a pH in the range from about 2 to 6 and at room temperature to 80 C an epihalohydrin with a salt of an amine of the formula H ₂ C = C (R) -CH ₂ ^ NR ⁰ (III) H ₂ C = C (R ') - CH ₂
implements. 7. The method according to claim 6, characterized in that the epihalohydrin with a polymer of an amine salt the formula H ₂ C = C (R) -CH ₂ N-R ° (Hl) H ₂ C = C (R *) - CH ₂
implements. 8. A method for activating a water-soluble polymer according to claim 2, characterized in that it is brought to a solids concentration of about 2 to about 10 $ at a pH value of 9 to 12 and this pH value during 1 to Maintains 5 hours at 5-50 ^° C. 9 «use of a polymer prepared according to claim 7 or 8 as an additive to paper pulp in an amount of from about 0 _F 05 to 7 wt .- ^, based on the fiber weight. 209813/1822