DE19638086A1 - Process for reducing the odor emission of aqueous polymer dispersions - Google Patents

Abstract

The present invention relates to the use of active coal for reducing odor emissions from aqueous polymer dispersions and products obtained therefrom. It also pertains to aqueous polymer dispersions containing 0.1 to 20 wt.% of active coal, their use as a binder for fibre composites, and the fibre composites themselves.

Description

The present invention relates to a method for reducing the odor emission of aqueous polymer dispersions and of products made using such polymers are available.

Aqueous polymer dispersions, in particular those by aqueous emulsion polymerization of ethylenically unsaturated mono mers are generally still volatile parts that z. T. be perceived as an unpleasant odor can. Volatile constituents are, for example, residual monomers, non-polymerizable impurities of the monomers, volatile Reaction products of the monomers which under the Polymerisationsbe conditions are formed, volatile degradation products of the polymers or the adjuvants contained in the polymer dispersions.

In general, it is therefore necessary, the Polymerisatdispersio by physical or chemical aftertreatment to desodo Center. As physical methods are, for example, destilla tive process, in particular the steam distillation and to call stripping with inert gases. Not all dispersio However, these are sufficiently stable compared to these methods that occasionally coagulum occurs, causing either one maneuverable filtration before further processing or make the dispersion completely unusable.

The lowering of the residual monomers can also be chemically radical after-polymerization, in particular under the action of redox initiator systems, such as In DE-A-44 35 423, DE-A-44 19 518 and in DE-A-44 35 422, he consequences. However, in this way non-polymerizable Ver bonds are not removed.

Both by the chemical as well as by the physical Des Of course, odorization only ent pollution which are present in the dispersion before processing. Volatile impurities that first occur during processing of the Dispersion (eg drying) are formed in this way not removed. Furthermore, it is a disadvantage that neither by the physical still through the chemical deodorization the fleeting components can be completely removed. This effect  is more pronounced, the higher the glass transition temperature of the respective Is polymers. Thus, polymers tend with glass transition temperatures above 50 ° C to include volatile compounds and if necessary, release again only when heated. This has to Result that the using such Polymerisatdispersio manufactured products are the volatile components if contained and release them when heating to the environment.

This problem arises for example in products that used in the automotive industry, especially in vehicle interiors become. There are, especially in sunlight, Tempe reached a significant release of ge can lead to odoriferous compounds.

The present invention is therefore based on the object To provide a method that allows odor-forming Kompo remove or neutralize in polymer dispersions Sieren. At the same time, this procedure should not be negative affect the stability of the dispersions.

The adsorbing effect of adsorbents with respect to volatile ger organic substances is known (see Römpp Chemielexi Kon, 9th ed., Georg-Thieme-Verlag, "Adsorbents" and "Adsorp tion "), however, there are no hin in the prior art note the use of adsorbents for the deodorization of Polymer dispersions. When using adsorbents such as Ak that is, there is a risk that coal may be used to stabilize it tion of the polymer dispersions necessary surface acti bind substances and thus the polymer in become stable.

Surprisingly, it has now been found that even a small Amount of activated carbon in polymer dispersions the odor-causing is able to bind volatile impurities so strongly that these both in the polymer dispersions and in the under Ver use of the polymer dispersions olfactorily no longer be perceived.

The present invention thus relates to the use of Ak activated carbon to reduce the odor emission of aqueous polyme dispersions and of products using Such polymer dispersions are available. The present The present invention also relates to a method for reducing the Ge odor emission of aqueous polymer dispersions, characterized characterized in that one disperses to the aqueous polymer activated carbon.  

The activated carbon used usually has a specific Surface in the range of 500 to 2500 m² / g, preferably in Be rich 800 to 1800 m² / g and in particular in the range of 1000 to 1500 m² / g (Langmuir surface according to DIN 66 131). Be Preference is given to activated carbon with a high content of micropores (Po diameter <2 nm; see also Ullmann's Encyclopedia of Tech Nical Chemistry, 5 ed, Vol. A5, p. 1126). The pore volume of used activated carbon is preferably in the range of 0.2 to f 1.4 ml / g, preferably 0.4 to 0.8 ml / g. Of these, take the micro preferably from 0.2 to 0.5 ml / g, in particular from 0.3 to 0.4 ml / g. Suitable activated carbons are commercially available.

Coals may also be used instead of or together with the activated carbon substance molecular sieves are used.

The activated carbon is preferably used in amounts of from 0.2 to 20% by weight, in particular 0.5 to 10 wt .-% and most preferably 0.8 to 5 wt .-%, based on the polymeric constituents of the polymer dispersion of dispersion, used.

In the process according to the invention, the activated carbon is preferably following a conventional deodorization process (e.g. physical or chemical deodorization, s. o.) With the polymer Discussion brought into contact. This is preferably done by introducing the activated carbon into the polymer after the usual procedure, as for the addition of powdered Solids to polymer dispersions are known, for example way by means of a dissolver. The addition is usually done at room temperature, but it can also be at elevated temperature be performed.

The activated carbon is required either for deodorization derliche period in the polymer dispersion and at closing by a usual method, for example by Filtration, again removed, or she will be together with the poly further processed merisatdispersion. The latter approach will preferably, in particular when the polymer dispersion po contains polymeric ingredients with glass transition temperatures above 50 ° C.

If the activated carbon to be removed after deodorization is their residence time in the polymer dispersion for the success of Deodorization not essential. It is usually in the range from 10 minutes to 5 hours, preferably 0.5 hours to 3 hours. The deodorization is usually done at room temperature, they However, it can also be used to speed up adsorption  equilibrium on the activated carbon at higher temperatures, before However, preferably not carried out above 80 ° C.

The grain size of the activated carbon used depends on the desired th deodorizing variant. If the activated carbon after the Des odorization be separated by filtration, it is recommended an activated carbon with a particle size above 100 microns, preferably <200 microns and in particular with a grain size in the range of 0.5 to use up to 3 mm.

As far as the activated carbon remain in the polymer dispersion should, is usually a finely divided activated carbon with a Particle size less than 200 microns, preferably less than 120 microns, esp special smaller 80 microns used. Such activated carbons are the Also known in the art (see Ullmann's Encyclopedia of Technical Chemistry, 3rd ed., Vol. 91 S 808) and commercially he hältlich.

With regard to the type of polymer dispersions used be There are no restrictions. This can be a Act primary dispersion, d. H. a polymer dispersion the by the method of free-radical, aqueous suspension or Emulsion polymerization of ethylenically unsaturated monomers unmit was obtained. It can also be a secondary disperse act, d. H. a by radical solution polymerization obtained polymer is subsequently in an aqueous polymer Dispersion transferred.

With regard to the monomers used for the polymerization also no restrictions, but preferably he will according to the invention method is used in polymer dispersions, as monomers C₄-C₈-dienes, such as butadiene, chlorobutadiene, isoprene or vinylaromatic compounds, such as styrene, α-methylstyrene, α-butylstyrene, vinyltoluenes or vinylchlorobenzenes. at The monomers mentioned are relatively easily under poly conditions of polymerization, volatile, foul-smelling compounds forms. Dienes form, for example, by reaction with sel over or with other ethylenically unsaturated compounds volatile cyclohexene derivatives. From vinyl aromatic compounds arise, for example, by oxidative degradation of the double bond Ketones or aldehydes. In addition, vinyl aromatic Mo often already produce connections due to production, in where the double bond is hydrogenated and the unpleasant Ge can also help.  

Alkyl is understood to mean linear or branched alkyl groups, eg. Methyl, ethyl, n -propyl, i -propyl, n -butyl, 2-butyl, i-butyl, t -butyl, n -pentyl, n -hexyl, 2-methylpentyl n -heptyl, 2-methylhexyl, 2 -Ethylhexyl, n-octyl, decyl, dodecyl, etc. By Cy cloalkyl is preferably meant cyclopentyl or cyclohexyl, which is optionally substituted with C₁-C₄-alkyl or halogen. Aryl is preferably phenyl or naphthyl, which may optionally also carry 1 to 4 substituents, which are selected from C₁-C₄-alkyl, halogen, C₁-C₄-alkoxy or hydroxy, wel Ches may also be ethoxylated. Under aryl alcohols preference is phenol or α- or β-naphthol which may also be optionally sub stituted (see above). By hydroxyalkyl aromas is meant benzene or naphthalene which carry at least one hydroxyalkyl radical and optionally also have further substituents (see above). The flag C _n -C _m - indicates the range for the possible number of C atoms in a compound or a group.

The process according to the invention for deodorization is preferred also used in polymers which are esters as monomers or Diesters of ethylenically unsaturated C₃-C₆ carboxylic acids or di carboxylic acids with C₂-C₁₀-alkanols, C₅-C₁₀-cycloalkanols C₆-C₂₀-aryl alcohols or C₇-C₂₁-Hydroxyalkylaromaten contain, since here by hydrolysis both under reaction conditions as well Under processing conditions, alcohols may be formed which are too malodorous aldehydes or ketones can be oxidized. Preference is given to the esters of acrylic acid, of methacrylic acid, the Crotonic acid, maleic acid, fumaric acid, itaconic acid or citraconic acid with C₂-C₁₀ alkanols, preferably with C₄-C₈ alkanols, for. With n-butanol, 2-butanol, n-hexanol, 2-hexa nol or 2-ethylhexanol, e.g. B. n-butyl acrylate, n-butyl methacrylate, Di-n-butyl maleate, di-n-butyl fumarate, 2-ethylhexyl acrylate or 2-ethylhexyl.

In addition to the monomers mentioned, the polymer dispersions also contain other monomers in copolymerized form. Here are in especially the olefins, such as ethylene, propene, 1-butene or 1-hexene, the vinyl or allyl esters of C₁-C₁₈ aliphatic monocarboxylic acid ren, z. For example, vinyl acetate, vinyl propionate, vinyl butyrate, vinyl hexa noate, vinyl 2-ethylhexanoate, vinyldodecanoate or vinyl stearate, the C₁-C₁₂-alkyl vinyl ethers or the nitriles of the above Mono- or dicarboxylic acids, eg. For example, acrylonitrile, methacrylonitrile, Ma to call linolenitrile or fumaronitrile.

Furthermore, the polymers can also, depending on the purpose in copolymerized form modifying monomers. Hereby han These are usually monomers, their homopolymers  have an increased water solubility, z. B. at the obengenann th, ethylenically unsaturated mono- or dicarboxylic acids whose Anhydrides, their amides, their mono- or dialkylamides, their N-alkylol derivatives or their hydroxyalkyl esters or ethyle Unsaturated sulfonic acids. Also suitable are N-vinyl derivatives of lactams. The polymer dispersions can also crosslinking monomers, in particular those containing at least two have ethylenically unsaturated bonds, for. B. polyfunctional nelle esters of said α, β-unsaturated carboxylic acids with di- or polyols, alkenyl esters of said ethylenically unsaturated th carboxylic acids and / or N, N'-dialkenylurea derivatives einpo included lymerized.

In addition, the polymer dispersions usually have nor auxiliaries, in particular surface-active substances, such as Protective colloids or emulsifiers, thickeners, defoamers and / or Preservative on. Its effect is from the erfindungsge According added activated carbon not or not to a considerable extent affected. Conversely, these compounds are the erfindungsge mäß effect of the activated carbon is not contrary.

The preparation of the polymer dispersions is known. In the all Commonly, it is carried out by free radical polymerization preferably in polar solvents, especially in water is carried out. To set the desired Molekularge In other words, the molecular weight can regulate substances with ver be used. Suitable molecular weight regulators are, for. Ver compounds which have a thiol group and / or a silane group (for example t-dodecyl, n-dodecylmercaptan or mercaptopropyltri methoxysilane), allyl alcohols or aldehydes such as formaldehyde, Ace taldehyde etc.

Suitable starters are z. As inorganic peroxides, such as sodium peroxodisulfate or azo compounds. The polymerization can ever after monomer composition as solution or emulsion polymers carried out.

If the polymer dispersion by emulsion polymerization is made, this is done in the usual way. In general one uses a protective colloid, such as polyvinyl alcohol, polyvinyl pyrrolidone or cellulose derivatives or anionic and / or nich cationic emulsifiers, such as ethoxylated mono-, di- or trialkyl phenols, ethoxylated fatty alcohols and alkali or ammonium salts of C₈-C₁₂ alkyl sulfates, of sulfuric monoesters ethoxylier ter C₁₂-C₁₈ alkanols, C₁₂-C₁₈ alkyl sulfonic acids, C₉-C₁₈ alkylaryl sulfonic acids or sulfonated alkyl diphenyl ethers. The poly  Merization temperature is generally in the range of 50 to 120 ° C, especially 60 to 100 ° C.

As already mentioned above, remains in a preferred Ausfüh tion form of the process according to the invention, the activated carbon in the Polymer dispersion. Polymerisatdispersionen, the activated carbon and products made using such Po lymerisatdisperionen were prepared, are thus also Ge object of the present invention.

The whereabouts of the activated carbon in the polymer dispersion is preferred, for example, when the polymer dispersions contain polymer constituents having glass transition temperatures above 50 ° C. Of course, the process according to the invention for desodorizing can also be carried out with polymer dispersions having a glass transition temperature below 50 ° C. By the glass transition temperature T _g is meant the limit of the glass transition temperature which, according to G. Kaniks (Kolloid-Zeitschrift + Zeitschrift fur Polymers, Vol. 190, page 1, equation i), tends to increase with increasing molecular weight; it is determined by the DSC method (DSC, mid-point temperature, ASTM D3418-82).

It is often helpful to estimate the glass transition temperature T _{g of} the dispersed polymer. According to Fox (TG Fox, Bull. Am Phys. Soc. (Ser. II) 1, 123 [1956] and Ullmann's Encyclopaedia of Industrial Chemistry, Weinheim (1980), 17, 18) applies to the glass transition temperature of copolymers at high molecular weights in a good approximation

where X¹, X²,. , , X ^{n is} the mass fractions 1, 2,. , , n and T _g ¹, T _g ²,. , ., T _g ⁿ the glass transition temperatures of each of only one of the monomers 1, 2,. , . mean n built-up polymers in degrees Kelvin. The latter are z. For example, from Ullmann's Encyclopedia of Indu strial Chemistry, VCH, Weinheim, Vol. A 21 (1992) p 169 or from J. Bandrup, EH Immergut, Polymer Handbook 3 ^rd ed., J. Wiley, New York, 1989 , known.

As already stated above, polymers which contain polymer constituents with glass transition temperatures T _g <50 ° C. are problematic in terms of their odor emission when heated.

It has now been found that in the polymer dispersions residual activated carbon also after the processing of such Po lymerisatdispersionen is able to the odor-forming sub adsorb and firmly bind so that they are also at elevated temperature can no longer be released.

Polymerisatdispersionen, the polymer components with glass transition temperature Turen above 50 ° C, for example, as Bindemit tel in fiber composites Use that increases in use ren temperatures are exposed, for example in Schichtpreß materials for rollers, bearings, insulation materials, floor coverings or thermoformable needled nonwovens, such as those in the Automotive construction can be used.

Polymerisatdispersionen for the production of thermally be loadable fiber composites are included in the Rule 20 to 80 wt .-%, preferably 40 to 75 wt .-%, in particular der 50 to 70 wt .-%, based on the polymeric constituents, at least one polymer which has a glass transition temperature above 50 ° C preferably above 80 ° C and in particular in the range of 100 to 150 ° C and 20 to 80 wt .-%, preferably 25 to 60 wt .-%, in particular 30 to 50 wt .-% of at least a second Polymerisates whose glass transition temperature by 40 K, preferably 60 to 150 K lower than that of the other polymer component. It can use both mixtures of said polymer components as well as core / shell polymers wherein the core is in usually the polymer component with the high glass transition temperature and the shell ent, the component with the lower glass transition temperature holds. The hard component is usually from 50 to 100% by weight. vinyl aromatic monomers, in particular styrene and / or α-Me ethylstyrene, α, β-ethylenically unsaturated nitriles, in particular Acrylonitrile and / or methacrylonitrile, and / or C₁-C₄-alkyl methacrylate laten, in particular methyl methacrylate, ethyl methacrylate or t-butyl methacrylate, and / or C₆-C₂₀-Arylmethacrylten example example, phenyl methacrylate and from 0 to 20 wt .-% modifying Monomers, e.g. Acrylic acid, methacrylic acid, maleic anhydride, Acrylamide, methacrylamide, N-methylolacrylamide, N-methylolmetha crylamide, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate or vinylsulfonic acid, vinylbenzenesulfonic acid, acrylamidopropane sulfonic acid or its alkali metal or ammonium salts and ge optionally crosslinking monomers, e.g. As vinyl or Al lyl (meth) acrylate, bicyclodocenyl (meth) acrylate, Gly koldi (meth) acrylate, diethylene glycol di (meth) acrylate, N, N'-divinyl or N, N'-Diallylimidazolidon constructed.  

The component with the lower glass transition temperature is contained in the Rule 20 to 100 wt .-% of monomers selected from vinyl ethers of C₃-C₁₀-alkanols, branched and unbranched C₃-C₁₀-olefins, C₁-C₁₀ alkyl acrylates C₅-C₁₀ alkyl methacrylates C₅-C₁₀ cycloalkyl crylates and methacrylates, C₁-C₁₀ dialkyl maleates, C₁-C₁₀ dialkyl polymerized fumarates and / or butadiene. This is it in particular, ethyl acrylate, n-propyl acrylate, n-butyl acrylate lat, isobutyl acrylate, s-butyl acrylate, n-hexyl acrylate, n-hexylme thacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, di-n-bu tylmaleinate, di-n-butyl fumarate and / or butadiene. Most notably it is preferably n-butyl acrylate, 2-ethylhexyl acrylate and / or butadiene. Furthermore, the component never contains that Glass transition temperature 0 to 80 wt .-% of those monomers einpolymeri As the main component for the component with the high Glass temperature were called (see above). Furthermore, the compo nente with the low glass transition temperature also modifying and optionally also crosslinking monomers (see above) copolymerized contain.

If the polymer dispersions as a binder for thermo malleable needled nonwovens used in automotive engineering is the polyme with the high glass transition temperature from 50 to 99.5% by weight of styrene, 0 to 49.5 wt .-% acrylonitrile and 0.5 to 5 wt .-% α, β-olefinic built up unsaturated C₃-C₆ monocarboxylic acids. The polymer with the low glass transition temperature is then usually from 20 to 70 wt .-% butadiene and 30 to 80 wt .-% styrene and optionally Acrylonitrile and from 0 to 5 wt .-% α, β-monoolefinically unsatd C₃-C₆ monocarboxylic acids whose amides and / or their N-Me thylolderivaten and from 0 to 5 wt .-% of crosslinking monomers built up. The polymer with the low glass transition temperature can but also alone from the abovementioned acrylic acid esters, ins special n-butyl acrylate and / or 2-ethylhexyl acrylate constructed his.

The preparation of both polymers with the high glass temp rature as well as the polymers with the low glass transition temperature is preferably carried out according to the above-described method of aqueous emulsion polymerization. The production of said Core / shell polymers are also preferably carried out by aqueous emulsion polymerization, by first the component with the high glass transition temperature and then the component with the low glass transition temperature polymerized. Such methods are described for example in DE-A-32 00 072, to the is hereby fully incorporated by reference.  

The production of fiber composites by Verfes fibers with the aid of the polymer dispersions according to the invention by known processes (eg Ullmann's Encyclopaedia Technical Chemistry, 4th ed., Vol. 23, 1983, pp. 738-742). There in the polymer dispersions except the activated carbon the additives suitable for the respective purpose give, in particular fillers such as clays or chalk. Han It is the fiber composites already around him mentioned thermoformable needled nonwovens for the automotive industry, starting from needled non-wovens, which from the usual Fa sern, z. As polypropylene, polyamide, polyester fibers, according to conventional methods (Römpp, Chemielexikon, Georg-Thieme-Verlag, Stuttgart-New York, 9th ed., P. 4550 and Litera cited there tur) were produced. These fiber webs are impregnated by bath kidney, foam impregnation, spraying, flattening or printing impregnated with the polymer dispersions. This can be the Disper If necessary, dilute with water or with conventional thickening be thickened to the desired processing viscosity to cease. The nonwoven treatment with the dispersion closes In general, a drying and tempering of the resulting Fiber composite on. The drying conditions depend on the Type of dryer used, usually the dry temperature between 80 and 160 ° C, in particular in the range of 110 to 130 ° C. Suitable dryers are, for example, circulating air or Fresh air drying cupboards or drum dryers. Often done the use of infrared heaters for preheating.

The fiber composites thus available are also prone to ther Mixer load above 70 ° C does not cause the emission of unpleasant odors. Their mechanical properties correspond to the Fa serverbundwerkstoffen, the herge without the use of activated carbon were presented.

Examples I. Preparation of the polymer dispersions

The preparation of the polymer dispersion was carried out according to Ver drive the semi-continuous radical emulsion Polymeri sation.

Dispersion A Feed 1: 9.8 kg styrene 5.8 kg of butadiene 0.1 kg of itaconic acid   0.24 kg of acrylic acid 0.3 kg Texapon®NLS (commercial product of Henkel KGaA) 5.5 kg of demineralized water Feed 2: 95 g of sodium peroxydisulfate 1.1 kg of demineralized water Template: 5% of feed 1 5% of feed 2 9.4 kg of demineralized water

The original was heated to 70 ° C and anpolymeri 30 minutes Siert. Subsequently, the remaining feed 1 for 4.5 hours. and simultaneously with feed 1 starting the remaining feed 2 added over 5 hrs. This was followed by 0.5 hours at 70 ° C afterpolymerized. Thereafter, the dispersion of a physi subjected to deodorization. The solids content of the receive NEN dispersion was 50 wt .-%.

Dispersion B

The preparation was carried out as in dispersion A, but was on of Texapon®NLS Dowfax®2A1 used as an emulsifier.

II. Odor Evaluation of the Dispersion

The dispersions were mixed with different amounts of activated carbon and then subjected to odor assessment by eight experienced odor assessors. The activated carbon used had the following characteristics:
Langmuir surface: 1213 m² / g (according to DIN 66 131)
Micropore volume: 0.357 ml / g
Pore diameter according to Langmuir: 19 angstroms.

Separate samples were made by stirring activated carbon into the Polymer dispersion prepared. To be judged 100 ml each The dispersion was placed in a 200 ml wide-mouth glass bottle crowded. For each examiner, one product was added to each product Prepare sample and this one after the other and against each other ge testing. The odor scale ranges from 1 for a very low Ge smell up to 5 for a very strong smell. The results are in Table 1 summarized.  

III. Odor test of the consolidated nonwovens

The nonwovens to be consolidated are commercial polyester needled nonwovens (PES fleece) or polyester / polypro ply-needled nonwovens having a polyester / polypropylene ratio of 80/20 (PES80 / PP20 nonwoven), each having a basis weight of 200 g / m².

The needle-punched nonwovens were washed to remove adherent Ge scavengers (eg Avivagen). After drying was the nonwoven with the dispersions of I. impregnated (120 g 50% Dispersion per 100 g of nonwoven fabric). Then it was 20 minutes dried at 120 ° C in a fresh air oven.

A. Odor test at 70 ° C

A rectangular test piece (7 × 24 cm) is placed in a 3 liter wide Neck bottle set and bottle with a glass stopper closed with the interposition of a piece of filter paper. It is then 20 hours at 70 ° C in a drying oven he warms. Then leave the bottle for 1 hour on room temp Then cool the glass stopper and exchange the glass stopper for one Flat glass lid made.

In the assessment, the procedure is to hold the breath, push the lid of the vessel slightly to the side and at the same time insert the nose as far as possible into the opening, inhale a small amount of air in several portions and then immediately close the vessel again. Depending on the perceived odor intensity, the sample is assessed according to the following scale:
0 = odorless
1 = just noticeable
2 = clearly perceptible
3 = noticeable, but not disturbing
4 = bearable
5 = just bearable
h = disturbing
7 = harassing
8 = very annoying
9 = unbearable.

Then let two to three breaths pass to the To condition smell again and judges the next one Sample. If you have judged all the samples, a new one Assessment, such that at the sample with the low first note begins. In this way one arrives at a final assessment of the respective sample. The samples are from six Assessed and then the average of the respective Judgment formed.

B. Odor test at 80 ° C.

The test is analogous to the test at 70 ° C with the following Än requirements:

• - The test specimen has an area of 150 cm²
• - The bottle is stored for 2 hours at 80 ° C.
• - After removal from the drying cabinet, the test vessel is closed first cooled to 60 ° C and carried out the odor test.
• - After evaluation by three examiners, the vessel will be renewed Stored at 80 ° C for 30 minutes and then at 60 ° C a re-examination by other examiners.
• - The following odor scale is used:
  • 1 = imperceptible
    2 = perceptible, not disturbing
    3 = clearly perceptible, but not disturbing
    4 = disturbing
    5 = strongly disturbing
    6 = unbearable

C. Smoke test

A test piece (31 × 8 cm) is made by means of an infrared radiator heated to 230 ° C. The aerosols are formed under Side lighting observed against dark background and judged by their intensity. The intensity scale ranges from 0 for no noticeable quality development until 5 for a very strong quality development. You can also place intermediate notes become. The test is performed twice for each sample. The  Result is the worst value. The results from A. to C. are summarized in Table 2.

Table 2

Claims (14)

1. Use of activated carbon to reduce odor emission of aqueous polymer dispersions and of products, the use of such polymer dispersions he are available. 2. Use according to claim 1, wherein the pore volume in the Activated carbon contained micropores in the range of 0.2 to 0.5 ml / g is. 3. Use according to one of the preceding claims, wherein the Activated carbon has a mean particle size below 200 microns has. 4. Use according to one of the preceding claims, wherein the Activated carbon has a specific surface (according to Langmuir) in Be rich from 500 to 2000 m² / g. 5. Use according to one of the preceding claims, wherein the aqueous polymer dispersion at least one C₄-C₈-diene, a vinyl aromatic compound and / or an ester or diester an α, β-unsaturated C₃-C₆ carboxylic acid having a C₁-C₁₀-Al kanol, C₅-C₁₀-cycloalkanol C₆-C₂₀-aryl alcohol or a Contains C₇-C₂₁-hydroxyalkyl in copolymerized form. 6. A method for reducing the odor emission of aqueous Po lymerisatdispersionen, characterized in that one to the aqueous polymer dispersion activated carbon. 7. The method according to claim 6, characterized in that the Activated carbon in amounts of 0.1 to 20 wt .-%, based on the polymeric constituents of the polymer dispersion used becomes. 8. The method according to claim 7, characterized in that the Activated carbon remains in the polymer dispersion. 9. Aqueous polymer dispersion containing 0.1 to 20% by weight, based on the polymeric constituents of the polymer disperse sion, activated charcoal as defined by any one of claims 2 to 4 is defined.   10. Aqueous polymer dispersion according to claim 9, comprising Polymers defined in claim 5. 11. Use of the polymer dispersions according to Ansprü che 9 or 10 as a binder for fiber composites. 12. Use according to claim 11, wherein it is in the Faserver Bundwerkstoff is a thermoformable needle felt. 13. fiber composites containing as binder a poly Merisatdispersion according to any one of claims 9 or 10. 14. fiber composites according to claim 13, wherein it is at the fiber composite material around a thermoformable needle fleece acts.