CA2036071A1

CA2036071A1 - Aqueous polymer dispersions

Info

Publication number: CA2036071A1
Application number: CA002036071A
Authority: CA
Inventors: Franz Matejcek; Maximilian Angel; Rudolf Schuhmacher
Original assignee: Individual
Current assignee: BASF SE
Priority date: 1990-02-16
Filing date: 1991-02-11
Publication date: 1991-08-17
Also published as: DE4004915A1; EP0442370B1; DE59107953D1; EP0442370A2; EP0442370A3

Abstract

O.Z. 0050/41405 Abstract of the Disclosure: Aqueous polymer dispersions obtainable by incorporating into an aqueous starting dispersion containing A) from 25 to 60 % by weight, based on the starting dispersion, of a polymer A as the disperse phase, built up from a) from 3 to 55 % by weight of one or more .alpha.,.beta.
monoethylenically unsaturated mono- or dicar-boxylic acids containing from 3 to 5 carbon atoms, of an anhydride of these acids or of a mixture of these monomers (monomers a), and b) from 45 to 97 % by weight of one or more other copolymerizable monomers (monomer b), in polymerized form and having, in disperse form, a mean particle size of from 20 to 400 nm, B) an effective amount of an emulsifier, and C) water as the remainder, at a temperature below the boiling point of pure water and above the glass transition point of the polymer A, from 5 to 60 mol-%, based on the number of moles of acid functions of the polymer A copolymerized in the form of the monomers a, of one or more of the divalent metals magnesium, calcium and zinc in the form of the oxide, hydroxide, carbonate or bicarbonate or in the form of a mixture of these basic salts, a process for their prepar-ation, binders prepared therefrom, and bitumen-treated roof sheeting produced using these binders.

Description

~C~7~

- o.z. 005~/41405 Aqueous polymer disper~ions The present invention relates to an aqueous polymer di persion obtainable by incorporating into an aqueous starting dispersion containing 5 A) from 25 to 60 % by weight, based on the starting dispersion, of a polymer A as the disperse phase, built up from a) from 3 to 55 % by weigh~ of one or more ~
monoethylenically unsaturated mono~ or dicar-10boxylic acids containing from 3 to 5 carbon atom~, of an anhydride of these acid~ or of a mixture of these monomers (monomers a), and b) from 45 to 97 ~ by weight of one or mors other copolymerizable monomers (monomer b), 15in polymerized form and having, in disperse form, a m~an particle size of from 20 to 400 nm, B) an effecti~e amount of an emulsifierl and C) water as the remainder, at a temperature below the boiling point of pure water and above ~he glass transition point of the polymer A,from 5 to 60 mol-%, based on the number of moles of acid function~ of the polymer A copolymerized in the form of the monomers a, of on~ or more of the divalent metals magnesium, calcium and zinc in the form of the oxide, hydroxide, carbonate or bicarbonate or in the form of a mixture of these ba~ic salts.
In addition, th~ present invention relates to a process for producing this polymer dispersion and to the use of the dispersion as a binder for a foaming, spray-ing, coating, bonding, sealing, coloring or impregnatingmaterial, to a binder prepared therefrom or nonwoven material for roof sheeting, and to nonwoven-based bitu-men-trsated roof sheeting con~aining this binder.
DE-B 10 51 436 describes aqueous polymer disper-sions having a polymer content of from 1 to 60 % by weight and containing, as the polymer, a copolymer built up from on~ or more lower alkyl e~ters of acrylic or 2 ~
- 2 - O.Z. 0050/41405 methacrylic acid and from 0.25 ~o 25 mol-% of acrylic, methacrylic or itaconic acid, and additionally containing a basic metal compound from the group comprising the oxides, hydroxides and other basic salts, for example the S acetates, of polyvalent metals, the amount of the basic metal compound being sufficient to neutralize from 0.25 to 25 mol-% of the carboxyl groups of the copolymer.
These aqueous synthetic resin dispersions are recommended for forming films which are to have increased internal strengthj the polymer dispersions which contain a rela-tively readily water-soluble metal compound, eg. an acetate, being preferred over polymer dispersions which contain a basic metal compound of lower water solubility, eg. an oxide or hydroxide, since the use of these les~
water soluble, basic metal compounds gives synthetic resin disper3ions which tend to form a sedLment on standing, are not entirely satisfactory with respect to their internal strQngth, and give films which are gener-ally cloudy. However, a disadvantage of synthetic resin disper4ions which contain a relatively readily water-soluble metal compound is that the anion~ causing the good water solubility of the metal compound, eg. the acetate anion, are generally on the one hand not inert and on the other hand are not a con~tituent of the water, which generally impairs tho properties of the ynthetic resin disporsions or means that they ~o not meet purity requirements. Accordingly, aqueou~ polymer dispersions containing polyvalent metals are also disadvantageous sincQ, although thay contain the metal, for example, in the form of an oxide or hydroxide, the metal i9, however, incorporated with the aid of non-inert auxiliary systems in order to avoid coagulation and sedimentation and to en~ure production of clear films of high internal strength. Examples of dispersions of this type are given, inter alia, in DE-A-18 11 247, in which, for example, the auxiliary system employed is ammonia, which is capable of complexing the metallic component~ in aqueous solution.

2 ~ 3 6 0 7 ~L

- 3 - O.Z. 0050/41405 It is an object of the present invention to provide aqueous polymer dispersions for producing films of high internal streng~h, avoiding said disadvantages, in particular even at an increased -~olids content. A
further object is to provide binders for nonwovens, which can be employed, for example, for bitumen-treated roof sheeting having good applicational properties, such as high heat resistance.
We have found that this ob~ect is achieved by the aqueous polymer dispersions defined at the outset.
We have furthermore found a preparation process for the preparation of these dispersions, their use as binders, nonwovens based on these dispersions, and bitumen-treated roof sheeting produced u~ing these nonwovens.
Good results are obtained when the polymer A i~
built up from 10 to 25% by weight of a) and from 75 to 90~ by weight of b).
Suitable monomers a are, inter alia, acrylic acid, methacrylic acid, maleic acid, fumaric acid, crotonic acid and itaconic acid. Preference is given to acrylic acid and methacrylic acid, the copolymerization of methacrylic acid being particularly advantageous.
Suitable monomers b are advantageously esters of acrylic or methacrylic acid with an aliphatic alcohol containing from 1 to 10 carbon atoms, the methyl, ethyl, isopropyl, n- and isobutyl, n-hexyl and 2-ethylhexyl esters being preferred. A particularly preferred acrylate i8 n-butyl acryla~e, which is advan~ageou ly copolymer-ized in amount~ of more than 50 ~ by weight, based on the total amount of the monomers. Good result3 are obtained by using 2-ethylhexyl esters.
Other suitable monomer~ b are aromatic vinyl compounds, such as styrane, vinyl e~ter~ of lower alkane-carboxylic acid3, such as vinyl acetate and vinyl pro-pionate, vinyl chloride, vinylidene chloride, nitriles oflower ~,~-monoethylenically unsaturated carboxylic acids, such as acrylonitrile and methacrylonitrile, and the 2~6~7:~

- 4 - o.Z. 0050/41405 amides of these car~oxylic acids, acrylates or methacryl-ates of lower polyhydric alcohols, un3aturated sulfonic and phosphonic acid~ and alkali metal salts thereof, such a~ ~odium vinylsulfonate, but also lower monounsaturated or polyunsaturated hydrocarbons, such as ethylene and butadiene. If the monomers b are alkali metal salts of monoethylenically unsaturated acids, their proportion by weight, based on the total amount of the monomers, should not exceed 1 % by weight. Methacrylonitrile, acrylamide, methacrylamide, hydroxyethyl acrylate, hydroxypropyl acrylate andtor in particular acrylonitrile is~are preferably copolymerized in amounts of from 4 to 15 ~ by weight, based on the to~al amoun~ of the monomers.
Groups of polymers A having good applicational propQrties have, in copolymerized form, the following monomer compositions:
I) from 3 to 45, preferably from 10 to 25 % by weight of monomer~ a from 55 to 97, preferably from 75 to 90 % by weight of one or more ester~ of acrylic and~or methacrylic acid with an aliphatic alcohol containing from 1 to lO carbon atom~, and from 0 to 40 ~ by weight of other copolymerizable monomers, II) from 3 to 30, preferably from lO to 30 ~ by weight of monomer~ a, from 35 to 52 ~ by weight of ~tyrene, and from 35 to 45 % by weight of butadiene, III) from 5 to 25, preferably from lO to 25 ~ by weight of monomar~ a, from 40 to 70 % by weight of vinyl acetate and/or vinyl propionate, and from 5 to 40 ~ by weight of ethylene, the group I compo~ition~ being particularly preferred.

- 5 - O.Z. ~050/~1405 ~ he groups IV to VI of polymers A having par-ticularly good water resi~tance have, in copolymerized form, the following monomer compositions:

IV) from 3 to 44.5 ~ by weight, preferably from 6 to 20 % by weight, of monomers a, from 55 to 96.5 ~ by weight, preferably from 60 to 90 % by weight, of one or more esters of acrylic or methacrylic acid with an aliphatic aicohol having from 1 to 10 carbon atoms, from 0.5 to S % by wèight, preferably from 0.9 to 4 % by weight, of N-methylolacryl-amide, N-methylolmethac~ylamide, acrylamidoglycolic acid or meth-acrylamidoglycolic acid, and from 0 to 40 ~ by weight of other copolymerizable monomer~, V) from 3 to 30, preferably from 10 to 25 % by weight of monomer~ a, from 35 to 48 ~ by weight of styrene, from 35 to 45 ~ by weight of butadiene, and from 0.5 to 5 % by weight, preferably from 0.9 to 4 ~ by wei~ht, of N-methylolacryl-amide, N-methylolmethacrylamide, acrylamidoglycolic acid or meth-acrylamidoglycolic acid, VI) from 5 to 20, preferably from 10 to 20 % by weight of monomers a, from 40 to 70 % by weight of vinyl acetate and~or vinyl propionate, from 5 to 40 % by welght of ethylene, and from 0.5 to S ~ by weight, preferably from 0.9 to 4 % by waight, of ~-methylolacryl-amide, N-meth~lolmethacrylamide, acrylamidoglycolic acid or meth-acrylamidoglycolic acid.

- 6 - o.z. 005 ~ 7 The percent by weight of the compositions I to VI
are each based on the total amount of the monomers.
N-Nethylol(meth)acrylamide is preferred over (meth)acrylamidoglycolic acid. Acrylamidoglycolic acid has the formula CH2=CH-CO-N-CHOH-COOH.
Good result~ are given by the group IV composi-tions.
In total, the proportions by weigh~ of the monomers participating in the structure of a polymer A
are preferably selected in such a manner that the polymer A has a glass transition poin~ of from -40 to 60C, preferably from -30 to 20C. The glass transition temperature can be measured in a known manner in accord-ance with AS~M Standard 3418/82 (midpoint temperature).
~he Tg can be estimated by applying the Fox relationship to the proportion~ by weight of the constituent monomers of a polymer. According to Fox (T.G. Fox, Bull. Am. Phys.
Soc. (Ser. IX) 1 (1956), 123), the following equation is a good approxLmation for the glas~ transition point ofcopolymers:

xl x2 xn + -- ~ .......
Tg T91 Tg2 T9n where Xl, X2, ..., Xn are the mas~ fraction~ of monomers 1, 2, ..., n, and Tg~, T~, ..., T~ are the qlass transition points in Relvin of the polymers in each case built up from only one of the monomers 1 t 2, or n. The gla~3 tran8ition point~ of these homopolymer of the abovemen~ioned monomer3 are in mo~t cases known and are li~ted, for example, in J. Brandrup, E.H. Immergut, Polymer Handbook l~t Ed., J. Wiley, Ne~
York, 1966, and 2nd Ed. J. Wiley, New York, lg75.

- 7 - O.Z. 0~50/41405 The aqueous starting di~p~rsions employed are preferably primary dispersions, ie. dispersions prepared by free-radical polymerization of the respective monomers a and b in aqueous medium under the known conditions of emulsion polymerization in the presence of water-soluble, free radical-forming initiator~ and emulsifiers. Preferred starting dispersions therefore comprise the polymer ~, emulsifier B and water as the remainder.
Particularly suitable water-soluble emulsion polymerization initiators are inorganic peroxides, of which particular preference i~ given to the peroxydisul-fates, that is those of sodium, potassium or ammonium.
Suitable emulsifiers are anionic, cationic and nonionic emulsifiers, preference being given to anionic emulsifiers, in particular used alone. Particularly ~ucce~sful emul~ifier~ are ethoxylated alkylphenols (EO
degree: from 3 to 30, alkyl radical: C~ to C10), ethoxy-lated fatty alcohols (EO degree: from 5 to 50, alkyl 2Q radical: CB to C25), the alkali metal ~alts of the sul-fated derivatives of these ethoxylation products and the alkali metal salts of alkyl~ulfonic acids, eg. sodium n-dodacylsulfonate or sodium n-tetradecyl~ulfonate, of alkylaryl~ulfonic acid~, eg. codium n-dodecylbenzenesul-fonate or qodium n-tetradecylbenzene~ulfonate, of higher fatty acids, 3uch as palmitic and ~tearic acid, and of disulfonated mono- or dialkyldiphenyl ethers.
The desired mean particle size a of the di~perse phase, from 20 to 400 nm, praferably from 20 to 300 nm (determined by the dynamic light ~cattering method, see for example E. L~ddecke and D. Horn, Chem. Ing. Tech. 54 (1982), 266 or H. Auweter and D. Horn, J. Coll. and Int.
Sci. 105 (1985), 399), can be controlled in a conven-tional manner by maan~ of the amount and type of the emulsifiers used, the polymer particles being larger the smaller the amount of emul~ifier u~ed. Ba-~ed on the amount of monomers employed, from 0.3 to 4 % by weight, ~ r.~ PJJ ~

- 8 - O.Z. 0050/41405 preferably from 0.4 to 3.5 ~ by weight, of emul~ifiers are generally employed. Aqueou~ starting dispersions whose light transparency (LT), after dilution to a solids content of 0.01 % by weight, and mea~ured using a commer-cially available photometer (at a wavelength of 0.546 ~m)and a path length of 25 mm relative to water (which i~
randomly given an LT of 100) is from 25 to 98, preferably from 65 to 95, are usually obtained. The LT of an aqueous polymer disper~ion is a qualitative measure of the mean particle size of the disperse phase. The emulsion poly-merization temperature and the amount of polymerization initiators used are set in a conventional manner such that a weight average molecular weight ~ of the dispersed polymer A of from 5 103 to 5 10~, preferably 105 to 2-106, is obtained. If necessary, molecular weiqht regulators, such as tert-dodecyl mercaptan, can also be used. Further possible assistants are buffer~, such as sodium pyrophos-phate. The emulsion polymerization temperature is gener-ally from 2S to 100C, preferably from 60 to 95C, and the polymerization initiator~ are usually used in amounts, ba~ed on the monomers, of from 0.1 to 3 ~ by weight.
The emulsion polymerization for the preparation of the polymer A can be carried out either batchwise or as a feed proces~, stepwise polymerization al~o being possible in both cases. Preference iR givQn to the feed process, in which some of the polymerization batch is heated to the polymerization temperature and the remain-der is subsequently added continuau~ly in ssparate feeds, of which one contains the monomer in pure or emul~ified form. Feeding of the monomers as an aqueous emulsion is preferred. The ~olid~ content of the ~tarting dispersion is preferably from 40 to 55 % by weight.
Of the suitable basic salts of the divalent metal~ magnesium, calcium and zinc, namely the oxides~
hydroxide~, carbonates and bicarbonate~, the o~ides are of particular interest. The metallic component u~ed is 2 ~3 ~ ~ 7 ~

- 9 - O.Z. 0050/41405 advantageously zinc, since it produces a particularly high internal strength of the films produced from the aqueous syn~hetic resin dispersions according to the invention and results, in a notable manner, in polymer dispersions having advantageous flow properties, in particular at high solids contents. The basic salts are generally incorporated as fine grains by stirring into the starting dispersion, whose p~ is preferably less than 3, for from 2 to 3 hours. Increased temperatures during stirring in favor incorporation of the basic salts.
The preferred ~rains have a sE~ surface area determined by the method of srunauer, Emmet and Teller (see P.W. Atkins, Phy~ikalische Chemie, VCH-Verlag, D-6940 Weinheim, 1987, page 799ff) of from 2 to 5 m2/g.
In an advantageous manner for application, the finely divided basic salts are stirred in after prior moistening, for example by preparing a paste having a solids content of from 10 to 80 ~ by weight, preferably from 20 to 70 % by weight, from the finely divided salt with addition of water, and subsequently incorporating the paste into the 3tarting dispersion. If necessary, small amounts of wetting agents can additionally be incorporated during preparation of the paste, it being ~5 expedient to employ the ~ame surfactants to prepare the starting dispersion as used during the emulsion polymerization.
Based on the number of moles of acid functions of the polymers A copolymerized in the form of the monomer~, with an anhydride group being counted as two a~id groups, advantagsously from 30 to 55 mol-% and particularly preferably from 40 to 55 mol-%, of one or more of the divalent metals magnesium, calcium or zinc in the form of an oxide, hydroxide, carbonate or bicarbonate are advan-tageously incorporated into the starting disper~ion. Theincorporation temperature is preferably 20C or more above the gla~s ~ransition point of the polymer A.

- 2 ~ 7 ~

- 10 - O.Z. ob'soJ4l40s The aqueous polymer dispersions according to the invention generally have no tendency toward sedLmentation on standing and hardly any coagulation occur~ during their preparation. Films produced from them are generally s clear and h~ve an increased internal strength. The latter is apparent, in particular, from the high modulus ~f elasticity, even at up to 200C, and increased ~alues or the tear strength. The water resistance also achieves good value~. Notably, the aqueous synthetic resin disper-sions according to the invention containing zinc as thedivalent metal have an increased frost resistance.
The aqueous polymer dispersions according to the invention are suitable a~ binders for foaming, ~praying, coating, bonding, sealing, coloring or impregnating materials. Depending on the particular application, it is also possible to add additives, such as fillers, external plasticizers, preservatives or other assistants. The aqueous synthetic resin di~persions according to the invention are particularly suitable as binders in non-2Q woven materials for the production of roof sheeting, inwhich the nonwoven materials are subjected to a bitumen bath at from about 180 to 200C. Preferred binders in nonwoven material~ for the production of roof sheeting are aqueous polymer di~per~ions who~e polymers A have a group I monomer composition and whose glass transition point is from -30 to 20C.
When used as binders in nonwovPn materials, the polymer dispersions according to the invention are expediently used in the dilute state, generally at an overall solids content of from 10 to 20 ~ by weight.
Nonwoven matarials are produced in a known manner by the con~olidation of nonwoven fiber fabrics, which may be spunbonded fabrics, or doubled, fiber reinforced, needle felted, rolled and/or ~hrink-treated nonwovens.
The application of the novel binders to the nonwoven is carried out in a customary manner by impregnating, foam impregnating, spraying, nip padding or printing, after - 11 - O.Z. 0050/41405 which exc~s binder is removed, for example by being squeezed off, and the impregnated nonwoven is then in ; general dried and heat-treated. The drying is carried out, for example, for from 1 to 15 minutes at from 100 to 200C. The amount of binder used is generally also such that the polymer content of the consolidated nonwoven fiber fabric is from 10 to 60~ by weight, based on the amount of fiber material.
Binders having particularly good wet strength are obtained if the polymer dispersions according to the invention, preferably those of composition II or III, in particular o~ composition I, are blende~ with from 0.5 to 20 parts by weight, preferably from 2 to 10 parts by weight, based on 100 parts by weight of the polymer of the aqueou~ polymer dispersion, of a methylol-containing resol or aminoplastic. These binders are used for non-woven materials for the production of roof sheeting. The above parts by weight are based on the dry weight of the polymer of the dispersion in accordance with DIN 53 189.
The resols and aminoplastics are, ~ery generally, condensation product~ based on carbonyl compounds, such as formaldehyde, and certain OH- or NH-containing com-pounds.
Aminoplastics, such as melamine or urea resins, are generally known, for example from Encyclopedia of Polymer Science and ~echnology, Interscience Publishers, 1965l Vol. 2, pag~ 1 ff., or Ullmann Encyclop~die der technischen Chemie, Verlag Chemie, 4th Edition, Voluma 7, pp. 403 to 423. The carbonyl compound usually employed is acetaldehyde, propionaldehyde, n-butyraldehyde, i obutyr-aldehyde, chloral, acetone or, in particular, formal-dehyde. Suitable N~-containing component~ are carbox-amide~, urethanes, sulfonamides, thiourea, guanidine, sulfurylamide, cyanamide, dicyanamide, guanamines and in particular urea and melamine. The condensation i~ carried out in a conventional manner with acid or base cataly~
usually at from 50 to 100C. Preference is given to - 12 - O.Z. 0050/4140~
water-soluble products which have a number average molecular weight of less than 3000, preferably from 400 to 1000, and contain free methylol groups.
Resols are preferred. They are likewise generally known from Encyclopedia of Polymer Science and Technology, Interscience Publisher~, 1969, Vol. 10, page 1 ff., and Ullmanns Encyclop~die der technischen Chemie, Verlag Chemie, Volume 18, 4th Edition, pages 245 to 257. Suitable carbonyl component~ are those men~ioned above. OH-containing compounds are phenol, which may be substituted by Cl- to Cl8-alkyl, such as p-t-butylphenol, p-isooctylphenol, p-phenylphenol, p-i~ononylphenol, amylphenol, cyclohexylphenol, dodecylphenol, cashew oil and in particular bisphenol A. The conden4ation is u~ually catalysed by bases or salt~ and i~ continued to a number average molecular weight of not more than 3000, preferably from 400 to 1000, so that free methylol groupc are present. Particular preference is given to a resol made from bisphenol A and formaldehyde in a ratio of from 1:2 to 1:4 containing about 3 to 4 methylol groups per molecule, in the form of an aqueous solution.
The resols or aminoplastics can be incorporated by methods known to those skilled in the art, preferably by mixing an aqueous ~olution thereof with the agueous di~persion. It may be appropriate to equalize the viscositie~ of the di~persion and solution by adding water in order to simplify mixing. The resultant mixture preferably has a p~ of from 6 to 8, in particular from 6.7 to 7.7.
Bitumen-treated, nonwoven-ba~ed roof ~heeting produced using the binders according to the invention has good ~ervice propertie~ and high heat re~i~tance.
It is generally produced, as de~cribed, for example, in US-A 4,518,658, by impregnating a nonwoven material, 5uch a~ spunbond, based on polye~ter~, for example polyethylene terephthalate, or a glass fiber~
reinforced nonwoven having a weight of from 120 to q~

- 13 - o.z. 0050/~1405 250 g/m2 with the binder so that, after drying, 100 parts by weight of the nonwoven generally contain from 10 to 25 parts by weight of the binder. Bitumen, usually at from about 180 to 200C, and, if de~ired, up to 5 parts S by weight, based on 100 parts by weight of bitumen, of customary auxiliaries, such as styrene-butadiene rubber, butadiene-nitrile rubber and inorganic fillers, are added to the nonwoven material treated in this w~y, to give a bitumen-treated roof web having a weight of from 2 to 8 kg/m2, particularly from 3 to 6 kg/m2.
EXAMPLES
Example 1 Various starting dispersion~ DAl to DA15 and comparative starting dispersions DAV1 to DAV3 DAl: A mixture of 591.3 g of water, 4.2 g of a 25 %
qtrength by weight aqueous qolution of sodium vinyl-sulfonate, 2.6 g of a 40 ~ strength by weight aqueous solution of sodium tetradecylsulfonate and 8~.3 g of an aqueous monomer emulsion Ml was heated to the polymerization temperature of 85C, with 43.6 g of an initiator solution comprising 12 g of sodium peroxydisulfate in 279 g of water being additionally added to the reaction mixture when the temperature had reached 70C. After polymerization for 15 minutes at 85C, the remainder of the initiator ~olution and ~he mono~er emul~ion Ml were added continuously to the reaction mixture via separate feeds over the course of 2 hours while maintaining the polymerization temperature, and the mixture was then polymerized for a further 1 hour.
Mls 591.4 g of water 1185 g of n-butyl acrylate 210 g of methacrylic acid 105 g of acrylonitrile 1.8 g of a 25 ~-strength by weight aqueous ~olution of sodium vinylsulfonate and 20~a7~

- 14 - O.Z. 0050/41405 14.6 g of a 40 % ~trength by weight aqueous solution of sodium n-tetradecyl-sulfonate.

DA2: A mixtuxe of 592.6 g of water, 4.2 g of a 25 strength by weight aqueou~ solution of sodium vin~l-sulfonate and 84.3 g of an aqueous monomer emulsion M2 was heated to ~he polymerization temperature of 85C, with 43.6 g of an initiator solution comprising 12 g of sodium peroxydi~ulfate in 279 g of water being additionally added to the reaction mixture when the temperature had reached 70Co After polymerization for 15 minutes at 85C, the remainder of the initiator solution and the monomer emulsion M2 were added continuou31y to the reaction mixture via separate feeds over the course of 2 hours while maintaining the pol~ymerization temperature, and the mixture was then polymerized for a further 1 hour.
M2: 590.2 g of water 1185 g of n-butyl acrylate 105 g of acrylonitrile 210 g of methacrylic acid 1.8 g of a 25 ~ ~trength by weight aqueous solution of sodium ~inylYulfonate and 17.2 g of a 40 % streng~h by wei~ht aqueous solution of sodium n-tetradecyl-~ulfonate.

DA3: A mixture of 592.6 g of water, 4.2 g of a 25 %
strength by weight aqueou~ Rolution of sodium vinyl-3ulfonate and 84.9 g of an agueou~ monomer ~mulsion M3 wa~ heated to the polymerization temperature of 85C, with 43.6 g of an initiator solution compri3ing 12 g of sodium pero~ydi~ulfate in 279 g of water being additionally added to the reaction mixture when the temparature had reached 70C. After - 15 - o.z. 0050/41405 polymerization for 15 minutes at 85C, the remainder of the initiator solution and the monomer emulsion M3 were added continuously to the reaction mixture via ~eparate feeds over the course of 2 hours while maintaining the polymerization temperature, and the mixture was then polymeri~ed for a further 1 hour.
N3: 530.2 g of water 1185 g of n-butyl acrylate 105 g of acrylonitrile 210 g of methacrylic acid 1.8 g of a 25 % ~trength by weight aqueous solution of ~odium vinyl~ulfonate 17.2 g of a 40 ~ strength by weight aqueous ~olution of ~odium n-tetradecyl-sulfonate and 75 g of a 20 % ~trength by weight aqueous ~olution of ethoxylated para-n-octyl-phenol (EO degree: 25) DAVl: A mixture of 592.6 g of water, 4.2 g of a 25 %
strength by weight aqueou~ solution of sodium vinylsulfonate and 84.7 g of an aqueou monomer emul~ion MVl was heated to the polymerization temperature of 85C, with 43.6 g of an initiator solution compri~ing 12 g of ~odium peroxydisulfate in 279 g of water being additionally added to the reaction mixture when the temperature had reached 70C. After polymerization for 15 minute3 at 85~C, the remainder of the initiator ~olution and the monomer emulsion MVl were added continuously to the reaction mixture via separate feeds over the cour3e of 2 hour~ while maintaining the polymerization temperature, and the mix~ure wa~ then polymerized for a further 1 hour.
MVl: 538.2 g of water 1185 g of n-butyl acrylate ~ 7 - 16 - O.Z. 0050/41405 105 g of acrylonitrile 210 g of methacrylic acid 1.8 g of a 2~ % strength by weight aqueous solution of sodium vinyl~ulfonate 3.7 g of a 40 ~ strength by weight aqueou~
solution of sodium n-tetradecyl-sulfonate and 75 g of a 20 % strength by weight aqueous solution of ethoxylated para-n-octyl-phenol (EO degree: 25) DA4: A mixture of 644 g of water, and 21.4 g of a 28 %
strength by weight aqueous solution of the sodium salt of the sulfated derivative of ethoxylated n-tetradecanol (EO degrees 2.5) wa~ heated to the polymeriæation temperature of 85C, with 24.9 g of an initiator solution comprising 9.6 g of sodium peroxydisulfate in 240 g of water being additionally added to the reaction mixture when the temperature had reache~ 70C. 5 minutes later, the remainder of the initiator solution and the monomer emul~ion M4 were added continuously to the reaction mixture via separate feeds over the course of 2 hours while maintaininq the temperature, and the mixtura wa~
then polymerized for a further 1 hour.
M4: 808 g of water 486 g of Btyrene 420 g of n-butyl acrylate 120 g of methyl methacrylate 174 g of methacrylic acid 128.5 g of a 28 ~ ~trength by weight aqueous solution of the sodium ~alt of the sulfated derivative of ethoxylated n-tatradecanol (EO degrees 2.5) DAS: A mixture of 659.4 g of water, and 106~8 g of an aqueous monomer emul~ion M5 was heated to the ~3~

17 - O.Z. 0050/41405 polymerization temperature of 85C, with 24.9 g of an initiator solution compri~ing 9.6 g of sodium peroxydisulfate in 240 g of water being additionally added to the reaction mixture when the temperature had reached 70C. After polymerization for 15 min-utes at 85C, the remainder of the ini~iator solu~
tion and the monomer emul3ion M5 were added continuously to the reaction mixture via separate feeds over the course of 2 hours while maintaining the polymerization temperature, and the mixture was then polymerized for a further 1 hour.
MS: 8 0 8 g o f water 486 g of 3tyrene 420 g of n-butyl acrylate 120 g of methyl methacrylat~
174 g of methacrylic acid 128.5 g of a 28 ~ strength by weight aqueou3 solution of the sodium salt of the ~ulfated derivative of ethoxylated n-tetradecanol (EO degree: 2.5) DA6: A mixture of 330 g of water, and 53.1 g of an aqueous monomer emulsion M6 was heated to the polymerization temperature of asoc~ with 12.4 g of an initiator solution comprising 4.8 g of sodium peroxydi~ulfate in 120 g of wat~r being additionally added to the reaction mixture when the temperature had reachod 70C. After polymerization for 15 min-utes at 85C, the remainder of the initiator ~olu-tion and the monomer emul~ion M6 were added continuou31y to the r~action mixture via ~eparate feeds over the course of 2 hour~ while maintaining the polymerization temperature, and the mixture wa~
then polymerized for a further 1 hour.
M6: 397.4 g of water 243 g of styrene 210 g of n-butyl acxylate ~3g~7~

- 18 - O.Z. 0050/41405 6 0 g o~ methyl mekhacrylate 87 g of methacrylic acid 60 g of a 20 % strength by weight aqueous solution of ethoxylated para-n-octyl-phenol (E0 degree: 25) and 6.4 g of a 28 % strength by weight aqueous solution of the sodium salt of the sulfonated derivative of ethoxylated n-tetradecanol (E0 degree: 2. 5 ) DA7: A mixture of 330 g of water, and 53.1 g of an aqueou~ monomer emulsion M7 was heated to the polymerization temperature o~ 85 C, with 12 . 4 g of an init~ator solu~ion compri~ing 4 7 8 g of sodium peroxydi~ulfate in 120 g of water being additionally added to the reaction mixture when the ~emperature had reached 70C. After polymerization for 15 min-utes at 85C, the remainder of the initiator solu-tion and the monomer emulsion M7 w~re added continuously to the reaction mixture via separate feed~ over the course of 2 hours while maintaining the polymerization temperature, and the mixture waY
then polymerized for a further 1 hour.
M7: 398.9 g of water 243 g of styrene 210 g of n-butyl acrylate 60 g of methyl methacrylate 87 g of methacrylic acid 60 g of a 20 % strength by weight aqueous solution of ethoxylated para-n octyl-phenol (E0 degree: 25) and 4.2 g of a 28 % str~ngth ~y weight aqueous solution of tha ~odium ~alt of the sulfated derivative of ethoxylated n-tetradecanol (E0 degree: 2~5) ~AV2: A mixturo of 330 g of water and 53.1 g of an aqueou~

2 0 3 6 ~ ~

- 19 - O.Z. 0050/41405 monomer emulsion MV2 was heated to the polymeriza-tion temperature of 85C, with 12.4 g of an initi-ator solution comprising 4.8 g of sodium peroxydi-sulfate in 120 g of water being additionally added to the reaction mixture when the tempera~ure had reached 70C. After polymeri~ation for 15 minutes at 85C, the xemainder of the initiator solution and the monomer emulsion MV2 were added continuously to the reaction mixture via separate feeds over the course of 2 hour~ while maintaining the polymer-ization temperature, and the mixtura was then polymerized for a further 1 hour.
MV2: 400.5 g of water 243 g of styrene 210 g of n-butyl acrylate 60 g of methyl methacrylate 87 g of methacrylic acid 60 g of a 20 ~ strength by weight aqueous solution of etho~ylated para-n-octyl-phenol (EO degree: 25j and 2.1 g of a 28 % strength by weight aqueous solution of the sodium salt o f the sulfated derivative of ethoxylated n-tetradecanol (EO degree: 2.5) DA8: A mixture of 591.5 g of water, 4.2 g of a 25 %
strength by weight aqueous solution of sodium vinyl-sulfonate and 84.6 g of an aqueou~ monomer emulsion M8 was heated to the polymerization temperature of 85C, with 43.6 g of an initiator solution comprising 12 g of sodium peroxydisulfate in ~79 g of watar being additionally added to the reaction mixture when the temperature had reached 70C. After polymerization for 15 minute~ at 85C, the remainder of the initiator solution and the monomer amulsion ~8 were added continuou~ly to the reaction mixture via separate feads over the cour~e of 2 hour3 whila maintaining the polymerization ~3~

- 20 - O.Z. 0050/41405 temperature, and the mixture was then polymerized for a further 1 hour.
M8: 583.9 g of water 1185 g of n-butyl acrylate 105 g of acrylonitrile 210 g of methacrylic acid 1.~ g of a 25 % s~rength by weight aqueous solution of sodium vinylsulfonate and 30 g of a 40 ~ strength by weight aqueous solution of sodium n-tetradecyl-sulfsnate.

DA9: As DAl, but the aqueous monomer emulsion M1 was replaced by a monomer emulsion M9.
M9: 591.5 g of water 1290 g of n-butyl acrylate 210 g of methacrylic acid 1.8 g of a 25 ~ strength by weight aqueous solution of sodium vinylsulfonate and 14.6 g of a 40 % ~trength by weight aqueous solution of sodium n-tetradecyl-sulfonate.

DA10: As DAl, but the queous monomer emulsion Ml was replaced by a monomer emulsion N10.
M10: 591.4 g of water 945 y of n-butyl acrylate 360 g of acrylonitrile 150 g of methacrylic acid 45 g of methacrylamide 1.8 g of a 25 % strength by weight aqueous solution of sodium vinyl ulfonate and 14.6 g of a 40 % strength by weight aqueous solution of sodium n-tetradecyl-sulfonate.

DA11: As DA1, but the aqueous monomer emulsion Ml was 2~3~

- 21 - o.z. 0050/41405 replaced by a monomer emulsion M11.
N11: 591.2 g of water 840 g of n butyl acrylate 105 g of acrylonitrile 375 g of mPthacrylic acid 180 g of methyl acrylate 1.8 g of a 25 % ~trength by weight aqueous solution of sodium vinylsulfonate and 14.6 g of a 40 ~ s~rength by weight aqueous solution of ~odium n-tetradecyl-sulfonate.

DAl2: As DAl, but the aqueous monomer emulsion ~l was replaced by a monomer emulsion Ml2 and the 12 g of sodium peroxydisulfate were replaced by 21 g of sodium peroxydi3ulfa~e.
M12: 591.5 g of water 840 g of n-butyl acrylate 105 g of acryloni~rile 175.5 g of acrylic acid 379.5 g of methyl methacrylate 1.8 g of a 25 % strength by weight aqueous solution of sodium vinylsulfonate 6 g of tert-dodecyl mercaptan and 14.6 g of a 40 ~ strength by weight aqueoug solution of sodium n-tetradecyl-sulfonate.

DA13: As DAl, but the aqueou~ monomer emul~ion Ml was replaced by a monomer emul3ion ~13.
M13: 591.4 g of wator 810 g of n-butyl acrylate 105 g of acrylonitrile 210 g of methacrylic acid 375 g of vinyl acetate 1.8 g of a 25 % 3trength by weight aqueous 2~b'~ 71 - 22 - O.Z. 0050/~1405 solution of sodium vinylsulfonate and 14.6 g of a 40 ~ s~rength by weight aqueous solution of sodium n-tetrad~cyl-sulfonate.

DA14: As DAl, but the aqueo~s monomer emul~ion M1 was replaced by a monomer emulsion M14.
M14: 591.2 g of water 1320 g of n-butyl acrylate 105 g of acrylonitrile 75 g of methacrylic acid 1.8 g of a 25 % strength by weight aqueou~
solution o~ sodium vinylsulfonate and 14.6 g of a 40 ~ strength by weight aqueous solution of sodium n-tetradecyl-lS sulfonate.

DA15: A misture of 136 kg of water, 1.33 kg of a 45 %
~trength by weight aqueous solution of a mixture of ~odium salts of disulfonated mono- and didodecyl-diphenyl ether~, 5.S kg of an initiator solution comprising 4 kg of sodium peroxydisulfa~e in 56 kg of water, and 59 kg of a monomer emulsion M15 is heated to the polymerization temperature of 90~C.
After polymerization for 20 minute~ at 90C, the remainder of the initiator ~olution and the monomer emulsion M15 were added continuously to the reaction mixturo via separate feeds over the cour~e of S hour~ while maintaining the polymerization temper-ature, and ~he mixture wa~ then polymerized for a further two hour~.
N15: 145.2 kg of water 40.0 kg of a 3 % ~trenqth by weight aqueous ~olution of ~odium pyropho~phste 12 kg of methacrylamide 200 kg of butadiene 148~0 kg of acrylic acid 203~7~

- 23 - O.Z. 0050/41405 7.2 kg of tert-dodecyl mercaptan 1.8 kg of a 15 ~ strength by weight aqueous solu~ion of sodium n-dodecylsulfate and 1.8 kg of a 45 % strength by weight aqueous ~olution of a mixture of sodium salts of disulfonated mono~ and didodecyl-diphenyl ethers.
DAV3: As DAl, but the aqueous monomer emulRion Ml was replaced by a monomer emulsion ~V3.
MV3: 421.5 g of water 1185 g of n-butyl acrylate 210 g of methacrylic acid 75 g of acrylonitrile 200 g of a 15% strength by weight aqueous solution of N-methylolmethacrylamide.

Small amounts of coagulate were removed by filtration (pore diameter: 1.2 10~4m) from the aqueous polymer disper~ions obtained in thi~ way.
Table 1 gives a summary of the essential features of the starting disper~ions DAl to DA15 and D~V1 and DAV2. The mean particle size a of the respective disperse phase was determined by the dynamic light scattering method u~ing an Autosizer IIC from ~alvern Instruments Ltd., Spring Lane South, Worcestershire, WR14 LAQ, England. The abbreviation SC denote~ solids content and Tg denoteR glass transition temperature. The Tg value~ were in all cases calculated by the Fox method, in which calculation a ~g valus of OC wa~ employed for the homopolymers of sodium vinyl~ulfonate and N-methylol-methacrylamide.

2 ~ 3 ~

- 24 - O.Z. 0050/41405 Starting SC LT ~(nm)Tg (C) dispersion (% by wt.) DAl 50 77 178.9 - 18 DA2 50 55 291.5 - 18 DA3 50.547 336.0 - 18 DAVl 49.9 6 473. 6 - 18 DA4 40.996 66.9 4~
DA5 40.586 108. 3 42 DA6 40.841 204.5 42 DA7 40O332 278.0 42 DAV2 39.9 9 439.7 42 DA8 50.166 - - 5 DA9 49.777 - - 26 DAlO 49.673 - 0 DAll 50.168 203.3 7 DAl2 50.~71 - 6 DAl3 50.374 185.9 0 DAl4 49.977 172.3 - 31 DA15 49.960 - - 13 DAV3 50.379 169.1 - 18 Zinc oxida-containing polymer dispersions DE1 to DE5 according to the invention and comparative dispersion~
DEVl to DEV6 An aqueous ZnO paste wa~ prepared by stirring 375 g of water into 625 g of ZnO (red ~sal quality from Netall und Farbwerke GmbH Grillo Werke AG, D-3380 Goslar, BET surface area from 3 to 5 m2), added in certain amounts to certain starting dispersions and stirred into these starting disper~ions at certain temperature~ for various times.
The coagulate formed was then removed by filtxa-tion (pore diamter: 1.2-10-~ m~, dried a~ 60C and deter~
mined gravimetrically. The di~per~ion obtained in this 203~n~

- 25 - O.Z. 0050/41405 way wa~ then left alone for 1 week, inspec~ed visually for sedimentation and used to produce a film.
DEl: Starting dispersion : 143.1 g of DA1 ZnO paste : 6.9 g Temperature : 25C
Stirring-in time : 2 h Coagulate : 0.0107 g After standing for one week, the dispersion DEl formed no ~ediment and produced clear films.
DE2: Starting dispersion : 136.6 g of DA2 ZnO paste : 6.5 g Temperature : 25C
Stirring-in tLme : 2 h Coagulate : 0.054 g After standing for one week, the dispersion DE2 formed no sediment and produced clear films.
DE3s Starting dispersion : 131.7 g of DA3 ZnQ pa~te : 6.3 g Temperature : 25C
Stirring-in time : 2 h Coagulate : 0.0277 g After standing for one week, the dispersion DE3 formed no sediment and produced clear films.
DEVl: Starting dispersion : 142.3 g of DAVl ZnO paste : 6.7 g Temperature : 25C
Stirring-in time : 2 h Coagulata : 0.0056 g After standing for one week, the dispersion DEVl formed a sQdiment.
DE4: Starting di8per8ion : 137.5 g o DA5 ZnO paste : 5.5 g T~mperaturQ : 70C
Stirring-in time : 2 h CoagulatQ : 0.0161 g After standing for one week, the dispersion DE4 fonmed no sediment and produced clear films.

7 ~
~ 26 - O.Z. 0050/41405 DE5: Starting dispersion : 130.8 g of DA6 ZnO paste : 5.2 g Temperature : 70C
Stirring-in time : 2 h Coagulate : O.0010 g After standing for one week, the dispersion DE5 formed no sediment and produced clear films.
DEV2: Starting dispersion : 143.4 g of DAV2 ZnO paste : 5.6 g Temperature : 25C
Stirring-in tLme : 4 h Coagulate s 0.0094 g After standing for one week, the di~persion DEV2 exhibited increased sedimentation and formed cloudy films.
DEV3: Starting disper~ion : 139 g of DAV2 Zno paste : 5.5 g Temperature : 70C
Stirring-in time : 2 h Coagulate : O.00631 g After standing for one week, the dispersion DEV3 exhibited sedimentation and formed cloudy films.
DEV4: Stasting dispersion : 140.6 g of DA5 ZnO pa~te : 5.6 g Tamperature : 25C
Stirring-in time : 4 h Coagulate : O.0387 g Ait~r ~tanding for one week, the dispersion DEV4 exhibited increased sedimentation and formed cloudy films.
DEV5: 5tarting dispersion s 132.7 g of DA6 ZnO paste : 5.3 g T~mperature o 25C
Stirring-in time : 4 h Coagulate : O.006S g After standing for one we0k, the disper~ion DEV5 exhibited sedimentation and formed cloudy film~.

2 ~ 3 ~
- 27 - O.Z. 0050/41405 DEV6: Starting dispersion : 124.0 g of DA7 ZnO paste : 5.0 g Temperature : 25C
Stirring-in time : 4 h Coagulate : 0.0078 g After standing for one week, the dispersion DEV6 exhibited sedimentation and formed cloudy films.

Flow behavior and frost stability a) Measurement methods The viszosity was determined in accordance with DIN 53019 using a rotation viscosimeter (Contraves -Rheometer 7978 STV FCN, Contraves AG, Zurich).
Cup 25 or 45 wa~ used; the measuremsnt was if possible carried out using ~peed I, II or III of the rheometer. To determine the frost stability, 400 g of dispersion were introduced into 500 ml capacity polyethylene bottles, and placed in a freezer at -50C for 8 hours. Tha dispersion was then thawed for 16 hours and assessed. A maximum of three cycles were carried out.
b) Test Flow behavior:
5.3 g of the ZnO paste from Example 2 were 2S stirrQd into 100 g of the starting dispersion DA1 at room temperature for 2 hours. A low vi~co~ity dispersion having a solids content of 50 % by weight was obtained. This dispersion was ~ub3equently diluted with water with ~tirring to a solids content of about 40 ~ by weight, and the viscosity was mea~ured:

~3~37i~
28 - O. Z . 0050/41405 Viscosity/mPas SC/% by wt. pH Cup Speed I II III

5.8 45 - 21 17 S 40 6.0 45 - - 8 501' 3.ol) 451) ~ 271' 22l) 1) Comparative ~alues for the starting dispersion DAl (without metal) Frost stabilitys The batches with different solids contents were te ted for frost stability. In the dispersion having a solids content of 50 ~ by weight, the viscosity increases, but the dispersion can be stirred up again. At a solidY content of 40 ~ by weight, the dispersion remains of low ~iscosity.
By contrast, the dispersion DAl (without metal) coagulates after the 1st cycle.

Testing of the internal strength at elavated temperature of nonwoven materials containing polymer dispersions according to the invention or comparative dispersions as binders.
a) Production of test strips The polymer dispersion wa~ applied by impregna-tion to a mechanically pre-strengthened 200 g/m2 polyester spunbond which is suitable for bitumen-treated roof sheeting, the exce~s bindar was then removed betwean two counterrotating xolls, and the binder-containing nonwoven material was exposed to a temperature of from 170 to 200C for 10 minutes.
The countarprassura of the roll~ was set 90 that the resultant material, from which rectan~ular test strips 320 mm in length and 50 mm in width were subsequently cut, contained 40 g of dry binder per m2.

- 29 - Z 005Q ~ 7 b) Te t procedure The test strips were clamped on their narrow sides (50 mm) between two opposing clamp~, of which one was fixed and the other movable. The movable clamp was attached to a position sensor ~nd, via a deflection roller, to an 8 kg weight.
The test strips were expo~ed to a temperature of 176C for 3 minutes and, as a measure of the inter-nal strength, the elongation (final length - initial length) and the contraction twidth of the test strip~ at the narrowe~t point) in each ca~e in mm, were determined.
c) Polymer dispersions used and measurement results - 5.3 g of the ZnO paste from Example 2 were stirred into 100 g of DA1 at 25C for 2 hours.
The dispersion obtained was then diluted to an o~arall solids content of 10 % by weight.
Elongation: 30.7 mm Contraction: 29.3 mm - A slurry of 2.2 g of calcium oxide in 5 g of water wa~ tirred into 100 g of DA1 at 25C for 2 hours. The resultant di~persion was then diluted to an overall solids content of 10 % by weight.
Elongation: 41.9 mm Contraction: 23.0 mm - A ~lurry of 1.6 g of magne~ium oxide in 5 g of water was stirred into 100 g of DAl at 25C for 2 hours. The re~ultant dispersion was then diluted to an overall ~olids content of 10 ~ by weight.
Elongation: 38.1 mm ~ontraction: 27.0 mm - A ~lurry of 1.4 g of MgO in 5 g of wa~er wa~
~tirred into 100 g of D~8 at 25C for 2 hour~.
The resultant disper~ion wa~ ~hen diluted to an o~erall solids content of 10 % by weight.

2~3~7~
- 30 ~ O.Z. 0050/41~05 Elongation: 38.9 mm Contraction: 21 mm - A slurry of 1.1 g of CaO in 5 g of wa~er was stirred into 100 g of DA8 at 25C for 2 hours.
The resultant dispersion was then diluted to an overall solids content of 10 ~ by weight.
Elongation: 35.7 mm Contraction: 22 mm - 4.5 g of the ZnO paste from Example 2 were stirred in~o 100 g of DA4 at 75C for 2 hours.
The disp~r~ion obtained was then diluted to an overall solids content of 10 % by weight.
Elongation: 35.8 mm Contraction: 23 mm lS - 4.4 g of ZnCO3-Zn(OH)2 were stirred into 100 g of DA1 at 25C for 2 hour~. The dispersion obtained was then diluted to an overall solids content of 10 % by weight.
Elongation: 33.2 mm Contraction: 26.5 mm - 5.4 g of the ZnO pa~ta from Example 2 were stirred into 100 g of DA12 a~ 75C for 2 hours.
The disper~ion obtained was then diluted to an overall solids content of 10 % by weight.
Elongation: 46 mm Contraction: 20.5 mm - 5.3 g of the ZnO paste from Example 2 were 3tirred into 100 g of DA9 at ~5C for 2 hours.
The dispersion obtained was then diluted to an overall solids content of 10 % by weigh~.
Elongations 40.5 mm Contraction: 22 mm - 1.6 g of the ZnO paste from Example 2 was stirred into 100 g of DA13 at 30C for 2 hours. The dispersion obtained wa~ then dilu~ed to an cverall ~olids content of 10 ~ by weight.
Elongation: 35.7 mm 2~36~
- 31 - O.Z. 0050/41405 Contraction: 25.5 mm _ 5.7 g of the ZnO paste from ~xample 2 were stirred into 100 g of DA11 at 75C for 2 hours.
~he dispersion obtained was then diluted to an overall solid~ content of 10 % by weight.
Elongation: 35 mm Contraction: 28.5 mm - l.9 g of the ZnO paste from Example 2 was stirred into 100 g of DA14 at 25C for 2 hours. The dispersion obtained was then diluted to an overall solids content of 10 % by weight.
Elongation: 45.9 mm Contraction: 16.5 mm - 3.7 g of the ZnO paste from Example 2 were ~tirred into 100 g of DA10 at 75C for ~ hours.
The disper~ion obtained was then diluted to an overall solid~ content of 10 % by weight.
Elongation: 38.3 mm Contraction: 25.5 mm In all ca~es, the disper3ion~ obtained before dilution exhibit, after ~tan ing for one week, no sedi~entation and produce clear film~.
- For compari~on, DAV3 wa~ used, likewise after dilution to a ~olid~ content of 10 % by weigh~.
Elongation: 53 mm Contraction: 14.5 mm EXANP~E S
Water re~i~tance te~ting of nonwoven materials containing the polymer disper~ion~ according to the invention.
DE6s A mixtur~ of 591.5 g of water, 2.6 g of a 40 %
~trength by weight aqueous solution of sodium tetradecyl~ulfonate, 4.2 g of a 25~ strength by weight aqueous ~olution of ~odium vinylsulfonate and 84.3 g of an aqueous monomer emul~ion M16 was heated to the polymerization temperature of B5~C, with 43.6 g of an initiator ~olution compri~ing 12 g of sodium peroxydisulfate in 279 g of water being 2 ~ 7 ~
- 32 - O.Z. 0050/41405 additionally added to the reaction mixture when the temperature had reached 70C. After polymerization for 15 minute~ at 85C, the remainder of the initiator solution and the monomer emulsion M16 were added continuously to the reaction mixture via separate feeds over ~he course of 2 hours while maintaining the polymeri~ation temperature, and the mixture was then polymerized for a further 1 hour.
Solids content of the dispersion 49.4 % by weight, LT 77 ~, a = 170.4 nm.
M16: 591.5 g of water 1170 g of n-butyl acrylate 210 g of methacrylic acid 105 g of acrylonitrile 15 g of acrylamido glycoli~ acid 1.8 g of a 25 % ~trength by weight aqueous solution of sodium vinylsulfonate and 14.6 g of a 40 % strength by weight aqueous solution of ~odium n-tetradecyl-sulfonate.
4.7 g of the ZnO pa~te men~ioned in Example 2 were stirred into 100 g of this dispersion at 25C, corresponding to 44 mol %.
DE7: The procedure is as in DE6, but the monomer emulsion M17 having the following composition is used:
M17O 591.5 g of water 1140 g of n-butyl acrylate 210 g of methacrylic aeid 105 g of acrylonitrile 45 g of acrylamidoglycolic acid 1.8 g of a 2S % strength by weight aqueous ~olution of ~odium vinylsulfonate and 14.5 g of a 40 % ~trangth by weight aqueous solution of sodiu~ n-tetradecyl-sulfonate.

~3~
- 33 - O.Z. 0050/41405 Solid~ content of the dispersion 49.5 % by weight, LT 49 96, d = 310 . 8 rllll~
4.7 g of the ZnO paste were stirred in as described for DE6.
5DE8: The procedure is as in DE6, but the monomer emulsion M18 having the following composition is used:
M18: 506.3 g of water 1185 g of n-butyl acrylate 10210 g of methacrylic acid 90 g of acrylonitrile 100 g of a 15 % strength by weiyht aqueous solution of N-methylolmethacryl~mide 1.8 g of a 25 % strength by weight aqueous 15solution o~ sodium vinylsulfonate and 14.6 g of a 40 ~ strength by weight aqueous solution of sodium n-tetradecyl-sulfonate.
Solids content of the dispersion 49.7 % by weight, 20LT 74 ~, d = 184.1 nm.
4.7 g of the ZnO paste were stirred in as described for DE6.
DE9: The procedure is as in DE6, but the monomer emulsion M19 having the following composition is useds M19s 421.3 g of water 1185 g of n-butyl acrylate 210 g of methacrylic acid 75 g of acrylonitrile 30200 g of a 15 ~ strength by weight aqueous solution of N-methylolmethacrylamide 1.8 g of a 25 % strength by weight aqueous solution of sodium vi.nylsulfonate and 14.6 g of a 40 ~ strength by weight aqueous 35solution of ~odium n-tetradecyl-sulfonate.

7 ~
- 34 - O.Z. 0050/41405 Solids content of the dispersion 49.5 % by weight, LT 7~ %, d - 166.5 nm.
4.7 g of the ZnO paste were stirred in as described for DE6.
DE10: The procedure is as in DE6, but the monomPr emul-sion M20 having the following composition is used:
M20: 294 g of water 1132.5 g of n-butyl acrylate 210 g of methacrylic acid 105 g of acrylonitrile 350 g of a 15 % strength by weight aqueous solution of N-methylolmethacrylamide 1.8 g of a 25 ~ ~trength by weight agueous solution of sodium vinylsulfonate and 14.6 g of a 40 ~ s~rength by weight aqueous solution of ~odium n-tetradecyl-sulfonate.
Solids content of the dicper~ion 49.5 ~ by weight, LT 78 ~
5.2 g of the ZnO pa~te were incorporated as described for DE6, corre~ponding to 49 mol %.
DEll: A mixture of 591.3 g of water, 2.6 g of a 40 %
strength by weight aqueous solution of sodium tetradecylsulfonate, 4.2 g of a 25% strength by weight aqueous solution of sodium vinylsulfonate and 84.3 g of the aqueous monomer emulsion Ml was heated to the polymerization temperature of 85C, with 43.6 g of an initiator solution comprising 12 g of sodium peroxydisulfa~e in 279 g of water being additionally added to the reaction mixture when the temperature had reached 70C. After polymerization for 15 minutes at 85C, the remainder of the initia~or solution and the monomer emulsion Nl were added continuou~ly to the reaction mixture via separate feed~ over the course of 2 hours while maintaining the polymerization temperature, and the mixture was then polymerized for a further 1 hour.

~Q3607~
- 35 - O.z. 0050/41405 Solids conten~ of the di~persion 50.0 % by weigh~, hT 77 %, d = 178.9 nm.
5.3 g of the ZnO paste were stirred in~o 100 g of this dispersion as described for DE6.
5 parts by weight of an aqueous solution of a resol having a solids content of 2 a % by weight were stirred into 95 parts by weight of this zinc-containing dispersion. The resol used comprised bis-phenol A and formaldehyde in a molar ratio of 1:3.7.
The alkali metal content was 5 ~.
Test method:
For the purpo~es of the present invention, the water resistance or wet streng~h of a nonwoven material is taken to mean the tear strength of the wet material after defined storage in water.
In order to make the effect of the binder clearly visible, a binder-free nonwoven comprising 70 ~ of cellulose and 30 % of viscose staple fiber with a weigh~
of 35 g/m2, produced by the wet nonwoven proces~
(E.A. Sch~ffmann, Wochenblat~ f. Papier~abrikation 97, No. 17 (1969), pp. 703-710), was chosen for the tests.
This material has no wet tear strength without binder.
Nonwoven pieces measuring about 30 cm by 22 cm were placed on a circulating polyester base woven material and, together with the woven material, passed through a shallow impregnation trough containing the binder liquor. The exces~ liquor was ~ubsequently removed from the material via a suction slot. The l quor con-centration and the vacuum applied to ~he suction slot were selected so that a binder application rate of about 50 % by weight, based on the fiber weight, wa3 achieved after drying. The drying temperature wa~ 170C.
Strips measuring 140 mm by 50 mm were ~tamped from the dried nonwoven materials. The strips were placed in water at room temperature containing 1 % of wetting agent. After one hour, the tear ~trength of the wet strips wa~ measured.

~3~7:~
- 36 - O.~. 0050/41405 Table 2 below shows the wet tear s~rengths obtained for the cellulose/viscose staple fiber nonwovens described containing various binders.

Binder Wet tear strength N/5 cm width

Claims

1. An aqueous polymer dispersion obtainable by incor-porating into an aqueous starting dispersion containing A) from 25 to 60 % by weight, based on the starting dispersion, of a polymer A as the disperse phase, built up from a) from 3 to 55 % by weight of one or more .alpha.,.beta.-monoethylenically unsaturated mono- or dicar-boxylic acids containing from 3 to 5 carbon atoms, of an anhydride of these acids or of a mixture of these monomers (monomers a), and b) from 45 to 97 % by weight of one or more other copolymerizable monomers (monomer b), in polymerized form and having, in disperse form, a mean particle size of from 20 to 400 nm, B) an effective amount of an emulsifier, and C) water as the remainder, at a temperature below the boiling point of pure water and above the glass transition point of the polymer A, from 5 to 60 mol-%, based on the number of moles of acid functions of the polymer A copolymerized in the form of the monomers a, of one or more of the divalent metals magnesium, calcium and zinc in the form of an oxide, hydroxide, carbonate or bicarbonate or in the form of a mixture of these basic salts.

2. An aqueous polymer dispersion as claimed in claim 1, whose polymer A has a glass transition point of from -40 to 60°C and which contains, based on the number of moles of the acid functions of the polymer a, copoly-merized in the form of the monomers a, from 40 to 55 mol-% of one or more of the divalent metals magnesium, calcium and zinc incorporated in the form of an oxide, hydroxide, carbonate or bicarbonate or in the form of a mixture of these basic salts.

3. An aqueous polymer dispersion as claimed in claim 1, whose polymer A in copolymerized form has one of the monomer compositions I to III:

- 38 - O.Z. 0050/41405 I) from 3 to 45 % by weight of monomers a from 55 to 97 % by weight of one or more esters of acrylic or methacrylic acid with an aliphatic alcohol containing from 1 to 10 carbon atoms, and from 0 to 40 % by weight of other copolymerizable monomers, II) from 3 to 30 % by weight of monomers a, from 35 to 52 % by weight of styrene, and from 35 to 45 % by weight of butadiene, III) from 5 to 25 % by weight of monomers a, from 40 to 70 % by weight of vinyl acetate, vinyl propionate or a mixture thereof, and from 5 to 40 % by weight of ethylene.

4. An aqueous polymer dispersion as claimed in claim 1, whose polymer A in copolymerized form has one of the monomer compositions IV to VI:

IV) from 3 to 44.5 % by weight of monomers a from 55 to 96.5 % by weight of one or more esters of acrylic or methacrylic acid with an aliphatic alcohol having from 1 to 10 carbon atoms, from 0.5 to 5 % by weight of N-methylolacrylamide N-methylolmethacrylamide, acryl-amidoglycolic acid or methacryl-amidoglycolic acid, and from 0 to 40 % by weight of other copolymerizable monomers, V) from 3 to 30 % by weight of monomers a, from 35 to 48 % by weight of styrene, from 35 to 45 % by weight of butadiene, and from 0.5 to 5 % by weight of N-methylolacrylamide, N-methylolmethacrylamide, acryl-- 39 - O.Z. 0050/41405 amidoglycolic acid or methacryl-amidoglycolic acid, VI) from 5 to 20 % by weight of monomers a, from 40 to 70 % by weight of vinyl acetate, vinyl propionate or a mixture thereof, from 5 to 40 % by weight of ethylene, and from 0.5 to 5 % by weight of N-methylolacrylamide, N-methylolmethacrylamide, acryl-amidoglycolic acid or methacryl-amidoglycolic acid.

5. An aqueous polymer dispersion as claimed in claim 1, which contains zinc oxide.

6. A process for the preparation of an aqueous polymer dispersion as claimed in claim 1, which comprises incorporating into an aqueous starting dispersion containing A) from 25 to 60 % by weight, based on the starting dispersion, of a polymer A as the disperse phase, built up from a) from 3 to 55 % by weight of one or more .alpha.,.beta.-monoethylenically unsaturated mono- or dicar-boxylic acids containing from 3 to 5 carbon atoms, of an anhydride of these acids or of a mixture of these monomers (monomers a), and b) from 45 to 97 % by weight of one or more other copolymerizable monomers (monomer b), in polymerized form and having, in disperse form, a mean particle size of from 20 to 400 nm, B) an effective amount of an emulsifier, and C) water as the remainder, at a temperature below the boiling point of pure water and above the glass transition point of the polymer A, from 5 to 60 mol-%, based on the number of moles of acid functions of the polymer A copolymerized in the form of the monomers a, of one or more of the divalent metals magnesium, calcium and zinc in the form of the oxide, - 40 - O.Z. 0050/41405 hydroxide, carbonate or bicarbonate or in the form of a mixture of these basic salts.

7. A method of using a polymer dispersion as claimed in claim 1 as a binder for a foaming, spraying, coating, bonding, sealing, coloring or impregnating material.

8. A nonwoven material which contains, as binder, a polymer of an aqueous polymer dispersion as claimed in claim 1.

9. A nonwoven material as claimed in claim 8, which contains from 0.5 to 20 parts by weight, based on 100 parts by weight of the polymer of the aqueous polymer dispersion, of a resol or aminoplastic.

10. Bitumen-treated roof sheeting based on a nonwoven material as claimed in claim 8.

11. Bitumen-treated roof sheeting based on a nonwoven material as claimed in claim 9.