It has hitherto not been possible to use thermal shaping processes directly on dispersions (mostly but not exclusively aqueous) of halogen-containing polymers, for example PVC slurry. The thermal lability inherent to halogen-containing polymers is an obstacle to this type of process, and an example of another factor present is that the water present which functions as a degradation catalyst. No water-soluble polymer stabilizers have been available permitting direct processing of the aqueous polymer dispersions produced during polymerization.

Conventional stabilizers, such as metal soaps or tin stabilizers, are unsuccessful in the direct processing of aqueous polymer dispersions, if only because of insolubility in water or incompatibility with water or immediate onset of hydrolysis.

There are many additives which can stabilize PVC. Compounds of the heavy metals lead, barium and cadmium are particularly well suited to this purpose, but are nowadays subject to criticism on environmental grounds or due to their heavy metal content (cf."Kunststoffadditive" [Plastics additives], R. Gachter/H. Müller, Carl Hanser Verlag, 3rd and 4th edn. , 1989 and 2001, pages 303-311 and"Kunststoff Handbuch PVC" [Plastics Handbook PVC], volume 2/1, W. Becker/D. Braun, Carl Hanser Verlag, 2nd edn. , 1985, pages 531-538; and also Kirk-Othmer:"Encyclopedia of Chemical Technology", 4th ed. , 1994, Vol. 12, Heat Stabilizers, pp. 1071-1091).

The object of the present invention was to provide a process for stabilizing a disper- sion of halogen-containing polymers.

The invention provides a process for stabilizing halogen-containing polymers in aqueous dispersion, where a stabilizer mixture compatible with the polymer disper- sion is added to an aqueous dispersion of the halogen-containing polymer. Particu- larly suitable stabilizer mixtures encompass perchlorate compounds and/or alkanolamines and/or salts of these.

The stabilizer mixtures which may be used according to the invention are compatible with the mostly aqueous polymer dispersion, or even soluble therein, and do not have any adverse effect on the dispersion of the polymer, for example breaking (coagulation) of the dispersion. For the purposes of this invention, the term disper- sions also includes suspensions, colloidal systems, and emulsions. The dispersions here (or suspensions, colloidal systems, or emulsions) are those of halogen- containing polymers in suitable dispersion or suspension media, as are produced in the production of SPVC, microSPVC or EPVC.

The provision of the process of the invention now makes it possible for the first time to realize, for example, unplasticized PVC coverings and coatings without prior drying of the PVC powder and without use of plasticizers. The stabilization process of the invention is, however, also applicable in the presence of plasticizers or lubricants, as long as these do not break the polymer dispersion.

The stabilizer systems presented of the process of the invention are used after polymerization, in a dispersion of the polymer, or else prior to or during the polym- erization procedure.

The resultant stabilized PVC dispersion, which is likewise provided by the present invention, can be applied to the article to be coated by means of a spray apparatus or of a doctor, or else by means of hot-melt rollers, and can be heat-treated in order to remove the adherent dispersion medium (e. g. water). The heat treatment at the same time melts, sinters, or gels the polymer on the article to be coated.

Examples of products of the process are polymer coatings on wood, felt, paper, metal, etc. , for example by dipping the materials mentioned into the dispersion (slurry) of the polymer and then (briefly) drying at an elevated temperature. The invention therefore also includes uses of the stabilized polymers of the invention for the production of articles and coatings.

It has been found that systems composed of at least one alkanolamine of the general formula (I) and/or of at least one perchlorate, in particular an alkaline earth metal perchlorate or alkali metal perchlorate, are particularly well suited for the process described for stabilizing halogen-containing polymers, in particular PVC.

The invention therefore provides a process for stabilizing halogen-containing poly- mers in aqueous dispersion, where a stabilizer mixture is added to an aqueous dispersion of the halogen-containing polymer and encompasses at least a) a perchlorate and/or b) an alkanolamine of the formula (I) where x= 1, 2 or 3 ; y= 1, 2,3, 4, 5or6 ; n = from 1 to 10 ; R1 and R2 = independently of one another H, Cl-C22-alkyl,- [- (CHR3a) y-CHR3b- O-] n-H,- [- (CHR3a) y-CHR36-0-] n-CO-R4, C2-C2o-alkenyl, C2-Ci8-acyl, C4-C8- cycloalkyl, where this may have OH substitution in the p-position, C6-Clo-aryl, C7-C10-alkaryl or C7-C10-aralkyl, or, if x = 1, R1 and R2 may also, together with the N, form a closed ring having from 4 to 10 members, composed of carbon atoms and, where appropriate, of up to 2 heteroatoms, or if x = 2, R1 may also be C2-Cls-alkylene which, at both (3-carbon atoms, may have OH substitu- tion and/or have interruption by one or more O atoms and/or one or more NR2 groups, or be dihydroxy-substituted tetrahydrodicyclopentadienylene, dihy- droxy-substituted ethylcyclohexanylene, dihydroxy-substituted 4, 4'- (bisphenol A dipropyl ether) ylene, isophoronylene, dimethylcyclohexanylene, dicyclo- hexylmethanylene or 3, 3'-dimethyldicyclohexylmethanylene, and if x = 3, Ri may also be trihydroxy-substituted (tri-N-propyl isocyanurate) triyl ; R3a and R3b = independently of one another C1-C22-alkyl, C2-C6-alkenyl, C6-C10- aryl, H or CH2-X-R5, where X = 0, S, -O-CO- or -CO-O-; R4 = C1-C18-alkyl/alkenyl or phenyl ; and Rs = H, C1-C22-alkyl, C2-C22-alkenyl or C6-Cio-aryl, and/or c) the salts of a) and b).

The invention further provides a process for stabilization in which use is made of stabilizer mixtures encompassing at least a) a perchlorate and/or b) a reaction product of a mono-or polyfunctional epoxide and ammonia or, respectively, a mono-or polyfunctional dialkyl (aryl)- or monoalkyl- (aryl) amine and/or c) salts of a) and b).

Examples of the alkanolamines of the general formula (I) are compounds where R1 and R2 = methyl, ethyl, propyl, butyl, cyclohexyl, octyl, lauryl, tetradecyl, hexadecyl, stearyl, oleyl, allyl, phenyl or benzyl or hydroxyalkyl and R3 = H, methyl, ethyl, propyl or butyl. Preference is given to alkanolamines where R'= lauryl, tetradecyl, hexade- cyl, stearyl, or oleyl, where R2 = hydroxyalkyl. It is also possible to use ethoxylates and propoxylates of triethanol-and triisopropanolamine, and also of fatty amines of vegetable or animal origin. Preference is given to trialkanolamines and monoal- kyl/alkenyldialkanolamines where R3 = H or methyl and y = 1, in particular fatty amines which have been reacted twice with ethylene oxide or with propylene oxide.

Other compounds with very good suitability can be found in the following list.

Methyl-or dimethylamine reacted once or twice with ethylene oxide or with propyl- ene oxide.

Propyl-or dipropylamine reacted once or twice with ethylene oxide or with propylene oxide.

Isopropyl-or diisopropylamine reacted once or twice with ethylene oxide or with propylene oxide.

Butyl-or dibutylamine reacted once or twice with ethylene oxide or with propylene oxide.

Isobutyl-or diisobutylamine reacted once or twice with ethylene oxide or with propylene oxide.

Pentyl-or dipentylamine reacted once or twice with ethylene oxide or with propylene oxide.

Isopentyl-or diisopentylamine reacted once or twice with ethylene oxide or with propylene oxide.

Hexyl-or dihexylamine reacted once or twice with ethylene oxide or with propylene oxide.

Isohexyl-or diisohexylamine reacted once or twice with ethylene oxide or with propylene oxide.

Heptyl-or diheptylamine reacted once or twice with ethylene oxide or with propylene oxide.

Isoheptyl-or diisoheptylamine reacted once or twice with ethylene oxide or with propylene oxide.

Octyl-or dioctylamine reacted once or twice with ethylene oxide or with propylene oxide.

Isooctyl-or diisooctylamine reacted once or twice with ethylene oxide or with propyl- ene oxide.

Nonyl-or dinonylamine reacted once or twice with ethylene oxide or with propylene oxide.

Isononyl-or diisononylamine reacted once or twice with ethylene oxide or with propylene oxide.

\ Decyl-or didecylamine reacted once or twice with ethylene oxide or with propylene oxide.

Isodecyl-or diisodecylamine reacted once or twice with ethylene oxide or with propylene oxide.

Undecyl-or diundecylamine reacted once or twice with ethylene oxide or with propylene oxide.

Isoundecyl-or diisoundecylamine reacted once or twice with ethylene oxide or with propylene oxide.

Dodecyl-or didodecylamine reacted once or twice with ethylene oxide or with propylene oxide.

Isododecyl-or diisododecylamine reacted once or twice with ethylene oxide or with propylene oxide.

Tridecyl-or ditridecylamine reacted once or twice with ethylene oxide or with propyl- ene oxide.

Isotridecyl-or diisotridecylamine reacted once or twice with ethylene oxide or with propylene oxide.

Tetradecyl-or ditetradecylamine reacted once or twice with ethylene oxide or with propylene oxide.

Hexadecyl-or dihexadecylamine reacted once or twice with ethylene oxide or with propylene oxide.

Octadecyl-or dioctadecylamine reacted once ortwice with ethylene oxide or with propylene oxide.

Eicosyl-or dieicosylamine reacted once or twice with ethylene oxide or with propyl- ene oxide.

Docosyl-or didocosylamine reacted once or twice with ethylene oxide or with propyl- ene oxide.

N-Methylbutylamine reacted with ethylene oxide or with propylene oxide.

N-Ethylbutylamine reacted with ethylene oxide or with propylene oxide.

Allyl-or diallylamine reacted once or twice with ethylene oxide or with propylene oxide.

Crotyl-or dicrotylamine reacted once or twice with ethylene oxide or with propylene oxide.

Octadecenyl-or dioctadecenylamine reacted once or twice with ethylene oxide or with propylene oxide.

Benzyl-or dibenzylamine reacted once or twice with ethylene oxide or with propylene oxide.

Cyclohexyl-or dicyclohexylamine reacted once or twice with ethylene oxide or with propylene oxide.

N-Methylcyclohexylamine reacted with ethylene oxide or with propylene oxide.

N-Ethylcyclohexylamine reacted with ethylene oxide or with propylene oxide.

4-Vinyl-1-cyclohexene diepoxide reacted twice with diethanol-or diisopropanolamine.

Dicyclopentadiene diepoxide reacted twice with diethanol-or diisopropanolamine.

Bisphenol A diglycidyl ether reacted twice with diethanol-or diisopropanolamine.

Trisglycidyl isocyanurate reacted three times with diethanol-or diisopropanolamine.

Preference is given to trialkanolamines and monoalkyl/ alkenyldialkanolamines where R3a and R3b = independently of one another H or methyl and y = 1.

The compounds of the general formula (I) where y = from 1 to 6, i. e. having up to 6 methylene groups between the amino group and the hydroxy-substituted carbon atom, have been found to be suitable for use as a PVC stabilizer in combination with a perchlorate salt.

According to the invention it is also possible to use compounds of the general formula (I) where x = 2, i. e. compounds which have two hydroxyalkylamino groups per molecule. Examples of these are N, N, N', N'- tetrakis (2-hydroxyethyl) ethylenediamine, N, N, N', N'-tetrakis (2-hydroxy-1- propyl) ethylenediamine, N, N, N', N'-tetrakis (2-hydroxyethyl) propylenediamine and N, N, N', N'-tetrakis (2-hydroxy-1-propyl) propylenediamine and N, N, N', N'-tetrakis (2- hydroxyethyl) hexamethylenediamine, preference being given to four-fold reactions of 1, 6-hexamethylene- or 1, 8-octamethylenediamine or neopentanediamine with ethylene oxide or with propylene oxide, or analogous reactions of bisaminomethylcy- clohexane or isophoronediamine or 4, 4'-diaminodicyclohexylmethane or 3,3'- dimethyl-4, 4'-diaminodicyclohexylmethane.

According to the invention, it is also possible to use compounds of the general formula (I) where x = 3, i. e. those which have three hydroxyalkylamino groups per molecule. An example of these is a reaction product of trisglycidyl isocyanurate with mono-or diethanolamine or mono-or dipropanolamine.

The alkanolamines of the general formula (I) are chemicals which can be purchased or can be prepared by known methods via N-alkylation of an appropriate amine or ammonia (cf. Kirk-Othmer, Vol. 2, Alkanolamines).

Examples of the preferred alkanolamines of the general formula (I) are tris (2- hydroxyethyl) amine, tris (2-hydroxy-l-propyl) amine, bis (2-hydroxyethyl)-2-hydroxy-1- propylamine, N-n-butyl-N, N-bis (2-hydroxyethyl) amine, N, N-bis (n-butyl)-N- (2-bis (2- hydroxyethyl) amine, N- (3-n-butyloxy-2-hydroxy-l-propyl)-N, N-bis (2- hydroxyethyl) amine, N- (1, 3-dihydroxy-2-hydroxymethyl-2-propyl)-N, N-bis (2- hydroxyethyl) amine, N, N-bis (2-hydroxyethyl)-N-palmitylamine, N, N-bis (2-hydroxy- ethyl)-N-oleylamine, N, N-bis (2-hydroxyethyl)-N-stearylamine, N- (2-hydroxyethyl)- morpholine and N-(2, 3-dihydroxy-1-propyl) morpholine, bishydroxyethylpiperazine and bishydroxyisopropylpiperazine and reaction products of glycidyl ethers with mono-or dialkylamine or ammonia, and also the alkanolamines derived therefrom, for example ethanolamine, diethanolamine, mono-and di-n-propanolamine, and mono-and di-isopropanolamine.

Very particular preference is also given to addition products of olefin oxides, such as octene oxide, decene oxide, dodecene oxide, tetradecene oxide, hexadecene oxide, octadecene oxide, eicosene oxide and docosene oxide, and also epoxystearyl alcohol with diethanol-or diisopropanolamine. These compounds with an OH function in the p-position at both ends of a relatively long alkyl chain, for example N- (2- hydroxyhexadecyl) diethanolamine, N- (2-hydroxy-3-octyloxypropyl) diethanolamine, N- (2-hydroxy-3-decyloxypropyl) diethanolamine, N- (2-hydroxy-3- octyloxypropyl) diethanolamine and bis-N- (2-hydroxy-3- phenyloxypropyl) ethanolamine are a particularly suitable component in the stabilizer systems of the invention.

This list is given only by way of example.

The perchlorates are known to the skilled worker. Examples are those of the formula M (ClO4) n, where M is H, Li, Na, K, Mg, Ca, Sr, Ba, Zn, Al, La, Ce or NH4 ; n is 1,2 or 3 as required by the valency of M. When use is made of aqueous dispersion systems it is also possible to use perchloric acid or to form this as active constituent in the medium.

Various commonly used supply forms (formulations) of the perchlorates may be used here; for example as salt or solution in water or in an organic solvent. Other exam- ples of these perchlorate formulations are perchlorate salts dissolved or complexed using alcohols (polyols, cyclodextrins) or using ether alcohols or ester alcohols or crown ethers, and another example is a dilute aqueous solution of perchloric acid.

Other embodiments are described in EP 0 394 547, EP 0 457 471 and WO 94/24200.

It is preferable to use sodium/potassium perchlorate salts.

The use of defined ethanolammonium perchlorate salts for inhibiting discoloration of chlorine-containing resin has also been disclosed in JP-A 61-9451 for"non-aqueous" PVC stabilization. These perchlorate salts have an ammonium salt structure and can be obtained by adding primary, secondary or tertiary ethanolamines to a perchloric acid solution.

Ammonium perchlorate salts are generally compounds sensitive to heat and shock and therefore are associated with a certain risk of explosion, making them unsuitable in principle for large-scale industrial applications in plastics processing.

This application also permits for the first time the risk-free use of ammonium per- chlorate via the use according to the invention of a dissolved, aqueous stabilizer system.

The invention also provides a stabilization process in which combinations of the stabilizer mixtures encompassing at least one perchlorate and at least one compound of the general formula (I) are used with at least one other conventional additive or stabilizer. Preference is given to the use of polyols and disaccharide alcohols, hydro- talcites, zeolites (aluminosilicates of alkali metals or of alkaline earth metals), fillers, metal soaps, other compounds of alkali metals or of alkaline earth metals, dyes, levelling aids, lubricants, plasticizers, pigments, epoxidized fatty esters and other epoxy compounds, antioxidants, UV absorbers, light stabilizers, optical brighteners and blowing agents.

Like the polymer, these additives or other stabilizers may be finely distributed in the dispersion and thus uniformly incorporated into the polymer through subsequent further processing.

The possible reaction products of the components used are also encompassed.

Examples of these additional components are listed and illustrated below (cf. "Hand- book of PVC-Formulating"by E. J. Wickson, John Wiley & Sons, New York 1993).

Polyols and disaccharide alcohols Examples of possible compounds of this type are: pentaerythritol, dipentaerythritol, tripentaerythritol, trimethylolethane, bis (trimethylolpropane), polyvinyl alcohol, bis (trimethylolethane), trimethylolpropane, sugars, sugar alcohols.

Of these, preference is given to the disaccharide alcohols.

It is also possible to use polyol syrups, such as sorbitol syrup, mannitol syrup and maltitol syrup.

Examples of the amounts of the polyols used are from 0. 01 to 20 parts by weight, advantageously from 0.1 to 20 parts by weight and in particular from 0.1 to 10 parts by weight, based on 100 parts by weight of PVC.

Hydrotalci The chemical composition of these compounds is known to the skilled worker, e. g. from the patents DE 3 843 581, US 4,000, 100, EP 0 062 813 and WO 93/20135.

Compounds from the hydrotalcite series may be described by the following general formula M2+ 1-xM3+x (OH) 2 (Ab-) xxb d H2O, where M2+ = one or more of the metals selected from the group consisting of Mg, Ca, Sr, Zn and Sn M3+ = Al or B, A"an anion of valency n, b is a number from 1 to 2, 0 < x < 0. 5, d is a number from 0 to 20.

Preference is given to compounds with An = OH-, ClO4-, HCO3-, CH3COO-, C6H5COO-, CO32-, (CHOHCOO) 22-, (CH2COO) 2, CH3CHOHCOO-, HPO3- or HPO42-.

Examples of hydrotalcites are Al2O3. 6MgO. CO2. 12H20 (i), Mg4, SAl2 (OH) 13. C03. 3. 5H20 (ii), 4MgO. Al203. C02. 9H20 (iii), 4MgO. Al203. C02. 6H20, ZnO. 3MgO. Al203. CO2. 8-9H20 and ZnO. 3MgO. Al2O3. CO2. 5-6H20.

Very particular preference is given to the types Alkamizer 2, Alkamizer P 93-2 (ex Kyowa) and L-CAM (lithium-modified hydrotalcite ex Fuji). It is preferable to use dehydrated hydrotalcites.

Zeolites (aluminosilicates of alkali metals and/or of alkaline earth metals) These may be described by the following general formula Mx/n [(AlO2) x (SiO2) y]. wH2O, where n is the charge on the cation M; M is an element of the first or second main group, such as Li, Na, K, Mg, Ca, Sr or Ba; y: x is a number from 0.8 to 15, preferably from 0.8 to 1.2 ; and w is a number from 0 to 300, preferably from 0.5 to 30.

Examples of zeolites are sodium aluminosilicates of the formulae Na2All2Sil2048. 27 H20 [zeolite A], Na6Al6Si6O24. 2 NaX. 7.5 H20, X = OH, halogen, ClO4 [sodalite] ; Na6Al6Si3o072. 24 H20 ; Na8Al8Si4o096. 24 H20; Na16Al16Si24O80. 16 H20 ; Na16AI16Si32096. 16 H20 ; Na56Al56Si136O384. 250 H20 [zeolite Y], Na86Al86Sui106O384. 264 H20 [zeolite X]; or the zeolites which can be prepared by partial or complete exchange of the Na atoms by Li atoms, K atoms, Mg atoms, Ca atoms, Sr atoms or Zn atoms, for exam- ple (Na, K) 10Al10Si22O64. 20 H20 ; Ca4.5Na3[(AlO2)12(SiO2)12]. 30 H20; K9Na3[(AlO2)12(SiO2)12]. 27 H20.

Very particular preference is given to Na zeolite A and Na zeolite P.

The hydrotalcites and/or zeolites may be used in amounts of, for example, 0.1 to 20 parts by weight, expediently 0.1 to 10 parts by weight and in particular 0.1 to 5 parts by weight, based on 100 parts by weight of halogen-containing polymer.

Fillers Fillers such as calcium carbonate, dolomite, wollastonite, magnesium oxide, magne- sium hydroxide, silicates, china clay, talc, glass fibres, glass beads, wood flour, mica, metal oxides or metal hydroxides, carbon black, graphite, rock flour, heavy spar, glass fibres, talc, kaolin and chalk are used. Preference is given to chalk (HANDBOOK OF PVC FORMULATING E. J. Wickson, John Wiley & Sons, Inc. , 1993, pp. 393-449) and reinforcing agents (TASCHENBUCH der Kunststoffadditive [Plastics Additives Handbook], R. Gachter & H. Müller, Carl Hanser, 1990, pp. 549-615).

The fillers may be used in amounts of preferably at least one part by weight, for example 5 to 200 parts by weight, expediently 5 to 150 parts by weight and in particular from 5 to 100 parts by weight, based on 100 parts by weight of PVC.

Metal soaps Metal soaps are primarily metal carboxylates, preferably of relatively long-chain carboxylic acids. Well-know examples of these are stearates and laurates, and also oleates and salts of relatively short-chain aliphatic or aromatic carboxylic acids, such as acetic acid, propionic acid, butyric acid, valeric acid, hexanoic acid, sorbic acid; oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, fumaric acid, citric acid, benzoic acid, salicylic acid, phthalic acids, hemimellitic acid, trimellitic acid, pyromellitic acid.

Metals which should be mentioned are: Li, Na, K, Mg, Ca, Sr, Ba, Zn, Al, La, Ce and rare earth metals. Use is frequently made of so-called synergistic mixtures, such as barium/zinc stabilizers, magnesium/zinc stabilizers, calcium/zinc stabilizers or cal- cium/ magnesium/zinc stabilizers. The metal soaps may be used either alone or in mix- tures. An overview of common metal soaps is found in Ullmann's Encyclopedia of Industrial Chemistry, 5th Ed., Vol. A16 (1985), pp. 361 et seq.

The metal soaps or mixtures of these may be used in amounts of, for example, 0.001 to 10 parts by weight, expediently 0.01 to 8 parts by weight, particularly preferably 0.05 to 5 parts by weight, based on 100 parts by weight of PVC.

Alkali metal and alkaline earth metal compounds For the purposes of the present invention, these are mainly the carboxylates of the acids described above, but also corresponding oxides or, respectively, hydroxides or carbonates. Mixtures of these with organic acids are also possible. Examples are LiOH, NaOH, KOH, CaO, Ca (OH) 2, MgO, Mg (OH) 2, Sr (OH) 2, AI (OH) 3, CaCO3 and MgC03 (and also basic carbonates, such as magnesia alba and huntite), and also fatty-acid salts of Na and of K. In the case of alkaline earth metal carboxylates and Zn carboxylates it is also possible to use adducts of these with MO or M (OH) 2 (M = Ca, Mg, Sr or Zn), so-called"overbased"compounds. In addition to the stabilizers according to the invention it is preferable to use alkali metal carboxylates, alkaline earth metal carboxylates and/or aluminium carboxylates. t Lubricants Examples of possible lubricants are: montan wax, fatty acid esters, PE waxes, amide waxes, chloroparaffins, glycerol esters and alkaline earth metal soaps, and fatty ketones, and also the lubricants, or combinations of the lubricants, listed in EP 0 259 783. Calcium stearate is preferred.

Plasticizers Examples of organic plasticizers are those from the following groups : A) Phthalate : such as preferably di-2-ethylhexyl, diisononyl and diisodecyl phthalate, also known by the common abbreviations DOP (dioctyl phthalate, di-2- ethylhexylphthalate), DINP (diisononyl phthalate), DIDP (diisodecyl phthalate).

B) Esters of aliphatic dicarboxylic acids, in particular esters of adipic, azelaic, and sebacic acid: preferably di-2-ethylhexyl adipate and diisooctyl adipate.

C) Trimellitic esters, such as tri-2-ethylhexyl trimellitate, triisodecyl trimellitate (mixture), triisotridecyl trimellitate, triisooctyl trimellitate (mixture), and also tri-C6- C8-alkyl, tri-C6-C10-alkyl, tri-c7-cs-alkyl and tri-C9-Cll-alkyl trimellitate. Common abbreviations are TOTM (trioctyl trimellitate, tri-2-ethylhexyl trimellitate), TIDTM (triisodecyl trimellitate) and TITDTM (triisotridecyl trimellitate).

D) Epoxy plasticizers : these are primarily epoxidized unsaturated fatty acids, e. g. epoxidized soybean oil.

E) Polymeric plasticizers : the commonest starting materials for preparing polyester plasticizers are: dicarboxylic acids, such as adipic, phthalic, azelaic or sebacic acid; diols, such as 1, 2-propanediol, 1, 3-butanediol, 1, 4-butanediol, 1, 6-hexanediol, neopentyl glycol and diethylene glycol.

F) Phosphoric esters: a definition of these esters is given in the abovementioned "Taschenbuch der Kunststoffadditive" ["Plastics Additives Handbook"], Chapter 5.9. 5, pp. 408-412. Examples of these phosphoric esters are tributyl phosphate, tri-2- ethylbutyl phosphate, tri-2-ethylhexyl phosphate, trichloroethyl phosphate, 2-ethylhexyl diphenyl phosphate, cresyl diphenyl phosphate, triphenyl phosphate, tricresyl phosphate and trixylenyl phosphate. Preference is given to tris (2-ethylhexyl) phosphate and Reofoso 50 and 95 (Ciba Spezialitatenchemie).

G) Chlorinated hydrocarbons (paraffins) H) Hydrocarbons I) Monoesters, e. g. butyl oleate, phenoxyethyl oleate, tetrahydrofurfuryl oleate and alkylsulfonates.

J) Glycol esters, e. g. diglycol benzoates.

A definition of these plasticizers and examples of the same are given in"Kunststof- fadditive" ["Plastics Additives"], R. Gachter/H. Müller, Carl Hanser Verlag, 3rd Ed., 1989, Chapter 5.9. 6, pp. 412-415, and in"PVC Technology", W. V. Titow, 4th Ed., Elsevier Publ., 1984, pp. 165-170. It is also possible to use mixtures of different plasticizers.

The plasticizers may be used in amounts of, for example, 5 to 20 parts by weight, expediently 10 to 20 parts by weight, based on 100 parts by weight of PVC. Rigid or semirigid PVC preferably comprises up to 10%, particularly preferably up to 5%, of plasticizer, or no plasticizer.

Pigments Suitable substances are known to the skilled worker. Examples of inorganic pigments are TiOz, pigments based on zirconium oxide, BaS04, zinc oxide (zinc white) and lithopones (zinc sulphide/barium sulphate), carbon black, carbon black-titanium dioxide mixtures, iron oxide pigments, Sb203, (Ti, Ba, Sb) O2, Cr203, spinels, such as cobalt blue and cobalt green, Cd (S, Se), ultramarine blue. Examples of organic pigments are azo pigments, phthalocyanine pigments, quinacridone pigments, perylene pigments, diketopyrrolopyrrole pigments and anthraquinone pigments. TiO2 in micronized form is also preferred. A definition and further descriptions are found in the"Handbook of PVC Formulating", E. J. Wickson, John Wiley & Sons, New York, 1993.

Epoxidized fatty acid esters and other epoxy compounds The stabilizer combination of the invention may, additionally and preferably comprise at least one epoxidized fatty acid ester. Possible compounds here are especially esters of fatty acids from natural sources (fatty acid glycerides), such as soya oil or rapeseed oil. However, it is also possible to use synthetic products, such as epoxi- dized butyl oleate. Use may also be made of epoxidized polybutadiene and polyiso- prene, if desired also in a partially hydroxylated form, or of glycidyl acrylate and glycidyl methacrylate as homo-or copolymer. These epoxy compounds may also have been applied to an alumino salt compound; in this connection see also DE-A-4 031 818.

Antioxidants Alkylated monophenols, e. g. 2, 6-di-tert-butyl-4-methylphenol, alkylthiomethylphe- nols, e. g. 2, 4-dioctylthiomethyl-6-tert-butylphenol, alkylated hydroquinones, e. g. 2,6- di-tert-butyl-4-methoxyphenol, hydroxylated thiodiphenyl ethers, e. g. 2, 2'-thiobis (6- tert-butyl-4-methylphenol), alkylidenebisphenols, e. g. 2, 2'-methylenebis (6-tert-butyl- 4-methylphenol), benzyl compounds, e. g. 3,5, 3', 5'-tetratert-butyl-4, 4'-di- hydroxydibenzyl ether, hydroxybenzylated malonate, e. g. dioctadecyl 2,2-bis (3,5-di- tert-butyl-2-hydroxybenzyl) malonate, hydroxybenzyl aromatics, e. g. 1, 3,5-tris (3,5-di- tert-butyl-4-hydroxybenzyl)-2, 4, 6-trimethylbenzene, triazine compounds, e. g. 2,4-bis- octylmercapto-6- (3, 5-di-tert-butyl-4-hydroxyanilino)-1, 3,5-triazine, phosphonates and phosphonites, e. g. dimethyl 2, 5-di-tert-butyl-4-hydroxybenzylphosphonate, acylaminophenols, e. g. 4-hydroxylauranilide, esters of beta- (3, 5-di-tert-butyl-4- hydroxyphenyl) propionic acid, beta- (5-tert-butyl-4-hydroxy-3-methylphenyl) propionic acid, beta- (3, 5-dicyclohexyl-4-hydroxyphenyl) propionic acid, esters of 3,5-di-tert- butyl-4-hydroxyphenylacetic acid with mono-or polyhydric alcohols, amides of beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid, for example, N, N'-bis (3,5-di-tert- butyl-4-hydroxyphenylpropionyl) hexamethylenediamine, vitamin E (tocopherol) and derivatives.

Examples of the amounts of the antioxidants used are from 0.01 to 10 parts by weight, advantageously from 0.1 to 10 parts by weight and in particular from 0.1 to 5 parts by weight, based on 100 parts by weight of PVC.

UV absorbers and light stabilizers Examples of these are: 2- (2'-hydroxyphenyl) benzotriazoles, such as 2- (2'-hydroxy-5'- methylphenyl) benzotriazole, 2-hydroxybenzophenones, esters of unsubstituted or substituted benzoic acids, such as 4-tert-butylphenyl salicylate, phenyl salicylate, acrylates, nickel compounds, oxalamides, such as 4, 4'-dioctyloxyoxanilide, 2,2'- dioctyloxy-5, 5'-di-tert-butyloxanilide, 2- (2-hydroxyphenyl)-1, 3,5-triazines, such as 2,4, 6-tris (2-hydroxy-4-octyloxyphenyl)-1, 3,5-triazine, 2- (2-hydroxy-4- octyloxyphenyl)-4, 6-bis (2, 4-dimethylphenyl)-1, 3, 5-triazine, sterically hindered amines, such as bis (2,2, 6, 6-tetramethylpiperidin-4-yl) sebacate, bis (2,2, 6,6-tetra- methylpiperidin-4-yl) succinate.

Blowing agents Examples of blowing agents are organic azo compounds and organic hydrazo com- pounds, tetrazoles, oxazines, isatoic anhydride, and also soda and sodium bicarbon- ate. Preference is given to azodicarbonamide and sodium bicarbonate and also mixtures of these.

Other additives which may be used are impact modifiers and processing aids, gelling agents, antistats, biocides, metal deactivators, optical brighteners, flame retardants, antifogging agents, compatibilizers, and dispersing agents, such as alkylsulphonates, arylsulphonates, polyvinyl alcohols, sorbitan esters, xanthogenates, alkyl ether derivatives, etc. (see also"Tensid-Taschenbuch" [Surfactants handbook], H. Stache, K. Kossvig, Carl Hanser Verlag, 3rd Edn. , 1990). A general description of additives is given in"Kunststoffadditive" ["Plastics Additives"], R. Gachter/H. Mutter, Carl Hanser Verlag, 3rd Edn. , 1989, and 4th Edn. 2001, and in"Handbook of Polyvinyl Chloride Formulating"E. J. Wilson, J. Wiley & Sons, 1993, and also in"Plastics Additives"G.

Pritchard, Chapman & Hall, London, 1st edition, 1998.

Impact modifiers are also described in detail in"Impact Modifiers for PVC", J. T.

Lutz/D. L. Dunkelberger, John Wiley & Sons, 1992.

The invention further provides compositions which comprise a halogen-containing polymer which has been stabilized by the process of the invention. Examples of this composition are polymer dispersions or else polymer powders after drying. The stabilizer mixture here has almost homogeneous distribution in the polymer. A feature of the polymer dispersions stabilized according to the invention is that (until further processing) they remain stable without coagulation, and they therefore exhibit no agglomeration of very finely distributed polymer particles which cannot be held in the dispersion, and therefore remain unbroken.

To achieve stabilization in the chlorine-containing polymer in these compositions, it is advantageous to use from 0.01 to 10 parts by weight, preferably from 0.1 to 5 parts by weight, of the compounds of the general formula (I) listed under (b), based on the entire dispersion.

Examples of the amount used of the perchlorates listed under (a) or solutions of these are from 0.001 to 5 parts by weight, advantageously from 0.01 to 3 parts by weight, particularly preferably from 0.01 to 2 parts by weight, based on the entire dispersion.

Finally, use may be made of amounts of from 0.01 to 10 parts by weight, preferably from 0.1 to 5 parts by weight, of the salts of (a) and (b) listed under (c).

Preference is given to compositions in which the ratio of the compounds (or mixtures of these) of the formula (I) listed under (b) to the perchlorate listed under (a), based on weight, is in the range from 0.01 : 1 to 50: 1.

The halogen-containing polymers are preferably chlorine-containing polymers, in particular PVC. Examples of the chlorine-containing polymers to be stabilized are: polymers of vinyl chloride, of vinylidene chloride, vinyl resins whose structure con- tains vinyl chloride units, for example copolymers of vinyl chloride and vinyl esters of aliphatic acids, in particular vinyl acetate, copolymers of vinyl chloride with esters of (meth) acrylic acid and with acrylonitrile, copolymers of vinyl chloride with diene compounds and with unsaturated dicarboxylic acids or anhydrides of these, for example copolymers of vinyl chloride with diethyl maleate, diethyl fumarate, or maleic anhydride, post-chlorinated polymers and copolymers of vinyl chloride, copolymers of vinyl chloride and of vinylidene chloride with unsaturated aldehydes, ketones and other compounds, for example acrolein, crotonaldehyde, vinyl methyl ketone, vinyl methyl ether, vinyl isobutyl ether, and the like ; polymers of vinylidene chloride and copolymers of the same with vinyl chloride and with other polymerizable compounds; polymers of vinyl chloroacetate and of dichlorodivinyl ether; chlorinated polymers of vinyl acetate, chlorinated polymeric esters of acrylic acid and of alpha- substituted acrylic acid; polymers of chlorinated styrenes, such as dichlorostyrene ; chlorinated rubbers; chlorinated polymers of ethylene ; polymers and post-chlorinated polymers of chlorobutadiene and copolymers of these with vinyl chloride, chlorinated natural and synthetic rubbers, and mixtures of the polymers mentioned with each other or with other polymerizable compounds. For the purposes of the invention, PVC includes copolymers with polymerizable compounds, such as acrylonitrile, vinyl acetate, or ABS, and the materials may involve suspension or emulsion polymers.

Preference is given to a PVC homopolymer or a PVC homopolymer combined with polyacrylates, or else polyvinyl alcohol and polyvinyl acetate.

Use may also be made of graft polymers of PVC with EVA, ABS and MBS. Other preferred substrates are mixtures of the abovementioned homo-and copolymers, in particular vinyl chloride homopolymers, with other thermoplastic and/or elastomeric polymers, in particular blends with ABS, MBS, NBR, SAN, EVA, CPE, MBAS, PMA, PMMA, EPDM and with polylactones, in particular those from the group ABS, NBR, NAR, SAN and EVA. The abbreviations used for the copolymers are familiar to the skilled worker and have the following meaning: ABS: acrylonitrile-butadiene-styrene ; SAN: styrene-acrylonitrile ; NBR: acrylonitrile-butadiene ; NAR: acrylonitrile-acrylate ; EVA: ethylene-vinyl acetate. Other particular materials which may be used are acrylate-based styrene-acrylonitrile copolymers (ASA).

Polymer compositions which comprise a mixture of from 25 to 75% by weight of PVC and 75 to 25% by weight of the copolymers mentioned as components (i) and (ii) are a preferred component here. Compositions composed of (i) 100 parts by weight of PVC and (ii) from 0 to 300 parts by weight of ABS and/or SAN-modified ABS and from 0 to 80 parts by weight of the copolymers NBR, NAR and/or EVA, PMA, PMMA, but in particular EVA, PMA and PMMA, are a particularly important component.

For the purposes of this invention, stabilization may also particularly be achieved by using dispersions or suspensions of very finely dispersed halogen-containing poly- mers, the polymers here being those described in more detail above which have undergone some degradation through processing, use or storage. Particular prefer- ence is given to recycled PVC material.

The compounds which may be used concomitantly according to the invention, and also the chlorine-containing polymers, are well known to the skilled worker and are described in detail in"Kunststoffadditive" [Plastics additives], R. Gachter/H. Müller, Carl Hanser Verlag, 3rd and 4th Edn. , 1989 and 2001; in DE 197 41 778 and EP-A 99 105 418.0 of 17.03. 1999, expressly incorporated herein by way of reference.

The stabilized halogen-containing, in particular chlorine-containing, polymer composi- tions of the invention are plasticized or unplasticized, or plasticizer-free or substan- tially plasticizer-free compositions.

The compositions of the invention in the form of unplasticized formulations are particularly suitable for packaging films, crash pad films (automobiles), foams, apparatus housings (computers, household devices), PVC-containing paints, coating substrates of any type, such as paper, paper board, carpets, textile, wood, metal, glass, felt, fibre materials, fibres, highly filled mouldings, coated decorative films, roofing films, office films or wallpapers.

Concomitant use may be made of lubricants or plasticizers, as long as the dispersion of the halogen-containing polymer remains unbroken.

The invention also provides uses of the compositions of the invention for the produc- tion or coating of articles, and the resultant articles. The invention in particular includes a process for producing unplasticized PVC coatings by dipping articles into a dispersion of polymer stabilized according to the invention.

Examples of the use of the compositions of the invention as a plastisol replacement are synthetic leather, floor coverings, textile coatings, wallpapers, coil coatings and underbody protection for motor vehicles, and examples of sinter PVC applications of the compositions of the invention are slush, slush mould, coil coatings, moulding and laminates.

The following methods for incorporating the stabilizers are advantageous: as a solution (there is an advantage of the inventive combination with this supply form, since the solvent can be water), emulsion or dispersion, or direct addition to the polymer dispersion (polymerization dispersion), during or after the polymerization.

The halogen-containing polymer stabilized according to the invention may be pre- pared in a manner known per se, but it is possible to dispense with the drying of the polymer powder, and instead use the entire polymer dispersion (polymerization dispersion) for further processing, and, where appropriate, mix other additives with the polymer. The stabilizers here may be added individually or in a mixture, or else in the form of what are known as masterbatches. This is particularly applicable to PVC.

Examples of uses for which PVC stabilized according to the invention is particularly suitable are packaging films, sheeting, foams, heavy profiles, filled moulding, construction profiles, sidings, office films and apparatus housings (computers, household devices), floor coverings, wallpapers and coatings, which are particularly preferred.

For further details in this connection see"Kunststoffhandbuch PVC", Volume 2/2 W. Becker/H. Braun, Carl Hanser Verlag, 2nd Edn., 1985, pp. 1236-1277.

The examples below illustrate the invention but do not limit the same. As is also the case in the remainder of the Description, the parts and percentages given are based on weight.

A feature of the polymer dispersions is that they remain stable with no coagulation until they are processed (production of a moulding).

Table 1 Stabilizers used Stabilizer Name 1 Solution of 30% sodium perchlorate monohydrate in water 2 Triethanolamine 3 Solution of 13% sodium perchlorate monohydrate in triethanolamine 4 Solution of 13% sodium perchlorate monohydrate in triisopropanolamine 5 Solution of 13% sodium perchlorate monohydrate in bis (2-hydroxyethyl)-substituted soya amine 6 Bis (2-hydroxyethyl)-substitied soya amine 7 Solution of 20% zinc chloride in water 8 Saturated aqueous sodium hydrogen carbonate solution 9 Epoxidized soya bean oil 10 Mark T 682 organotin stabilizer (commercially available product from Crompton Vinyl Additives GmbH) Example 1: Statistical heat test (thermal stability) 1 g of a mixture of 100 parts of an aqueous PVC dispersion (1) and [X] parts of a stabilizer (described in Table 1) were placed on an aluminium dish and dried at 190°C in a drying cabinet for 10 sec and gelled at 190°C for a further 10 sec. Using a 2-minute interval, the specimen was then subjected to 10 minutes of heat-ageing at 190°C.

The discoloration of the specimen was determined as Yellowness Index (YI) to ASTM D1925-70. Low values mean good starting colour and therefore good stabilization.

PVC dispersion (1) : composed of about 40% of PVC and 60% of water with addi- tives, the additives being composed of polyvinyl alcohol, a stearate and a phthalate.

Table 2 No. Stabilizer [X] parts YI after 10 min 1 without stabilizer 103.0 2 1 0. 5 77. 9 3 2 0. 5 64. 4 4 3 0.5 47.8 5 4 0.5 55.5 6 5 1.0 49.9 6 5 1.0 49.9 7 6 1.0 86.2 8 7 0. 1 116.0 9 8 1.0 111.0 10 9 1.0 97.0 11 10 0. 1 92. 2 The comparative Examples 8 to 11 in Table 2 show poorer thermal stability, as can be seen from the YI values at 10 min.

Example 2: Statistical heat test (starting colour) The specimens tested were produced as described in Example 1. The same PVC suspension (1) was used.

Table 3 No. Stabilizer [X] parts YI after 2 min without stabilizer 18.5 2 1 0. 5 1. 6 3 2 0. 5 3. 9 4 3 0. 5 3. 6 5 6 1.0 5.6 6 7 0.1 9.9 7 8 1.0 20.8 8 9 1. 0 4. 4 9 10 0. 1 5. 0 Table 3 shows that stabilization according to the invention provides improved starting colour.

Example 3: Statistical heat test (thermal stability) The specimens tested were produced as described in Example 1.

PVC dispersion (2): composed of about 60% of PVC and 40% of water with additives composed of an alkylbenzoic acid derivative, a stearate and an alcohol.

Table 4 No. Stabilizer [X] parts YI after 10 min 1 without stabilizer 87.3 2 1 0.5 74.6 3 2 0.5 78.2 4 3 0.5 32.9 5 3 1.0 44.4 6 4 0.5 63.2 7 5 1.0 46.8 8 6 1.0 69.3 9 7 0.1 110.0 10 8 1.0 102.0 11 10 0.1 90.3 The comparative Examples 9 to 11 in Table 4 show poorer thermal stability, as can be seen from the YI values at 10 min.

Example 4: Statistical heat test (starting colour) The specimens tested were produced as described in Example 3. The same PVC dispersion (2) was used.

Table 5 No. Stabilizer [X] parts YI after 2 min 1 without stabilizer 16.4 2 1 0. 5 6. 8 3 2 0. 5 4. 3 4 3 0. 5 7. 2 5 3 1.0 0.1 6 4 0. 5 2. 3 7 5 1. 0 3.2 8 6 1.0 3.7 8 6 1.0 3.7 10 8 1.0 20.6 11 10 0.1 9.4 Table 5 shows that stabilization according to the invention also provides better starting colour.

Example 5: Statistical heat test The specimens tested were produced as described in Example 1.

PVC dispersion (3): composed of about 40% of PVC and 60% of water with additives composed of an alkylsulphonate, a sorbitan ester and a stearate.

Table 6 No. Stabilizer [X] parts I 2 min 10 min 1 without stabilizer 7.9 99.6 2 1 0.5 6.4 68.3 3 2 0.5 2.4 38.3 4 3 0. 5 2. 5 15. 1 5 I 4 I 0.5 2. 5 1 31. 4--1 The way in which stabilization of the invention acts is apparent in the improvement in starting colour (YI after 2 min) and in better thermal stability (YI after 10 min).

Example 6: Statistical heat test The specimens tested were produced as described in Example 1.

PVC dispersion (4): composed of about 40% of PVC and 60% of water with an additive composed of a sorbitan ester.

Table 7 YI No. Stabilizer [X] parts 2 min 10 min 1 without stabilizer 0.1 89.6 2 1 0. 5 0. 5 61. 9 3 2 0. 5-0. 2 89. 6 4 3 0. 5-2. 7 16. 3 5 4 0. 5-0. 7 36. 0 The way in which stabilization of the invention acts is apparent in the improvement in starting colour (YI after 2 min) and in better thermal stability (YI after 10 min).

Example 7: Statistical heat test The specimens tested were produced as described in Example 1.

PVC dispersion (5): composed of about 50% of PVC and 50% of water with additives composed of a 4-alkylbenzenesulphonic acid derivative and a lubricant.

Table 8 YI No. Stabilizer [X] parts 2 min 10 min 1 without stabilizer 5.6 66.8 2 1 0. 5 2. 7 44. 1 3 2 0.5 1.1 37.4 4 3 0.5 1.2 24.4 5 4 0. 5 0. 9 24. 5 The way in which stabilization of the invention acts is apparent in the improvement in starting colour (YI after 2 min) and in better thermal stability (YI after 10 min).

Example 8: Dispersion stability A ready-to-use coating slurry was prepared by blending 100 parts of an aqueous PVC dispersion (1) and [X] parts of a stabilizer, and stability was assessed immediately after preparation and after 30 days.

PVC dispersion (1) : composed of about 40% of PVC and 60% of water with additives composed of polyvinyl alcohol, a stearate and a phthalate.

Table 9 Stability after No. Stabilizer [X] Preparation 30 days parts 1 without stabi-dispersion dispersion lizer 2 1 0.5 dispersion dispersion 3 2 0.5 dispersion dispersion 4 3 0. 5 dispersion dispersion 5 4 0.5 dispersion dispersion 8 7 0. 1 coagulates coagulates 9 8 1.0 coagulates coagulates 10 9 1.0 dispersion coagulates 11 10 0.1 coagulates coagulates It was clear that stable ready-to-use PVC dispersions could be prepared using the stabilizers of the invention.

Example 9: PVC coatings 2 g of a mixture of 100 parts of an aqueous PVC dispersion (1) and 1.0 part of a stabilizer as described in Table 1 was applied to a"K-300"cellulose filter plate (diameter 6 cm) from the company Seitz and heated in a drying cabinet for 30 min at 60°C. The coated filter plate was then subjected to heat-ageing at 190°C. The discoloration of the specimen was determined as Yellowness Index (YI) to ASTM D1925-70. Low values mean good starting colour and therefore good stabilization.

PVC dispersion (1) : composed of about 40% of PVC and 60% of water with additives composed of polyvinyl alcohol, a stearate and a phthalate.

Table 10 No. Stabilizer YI after 10 min 1 without stabilizer 80.6 2 1 52. 0 3 2 51. 6 4 3 45. 2 5 4 51. 9 6 5 50. 6 7 6 60. 7 8 7 > 120 9 8 111.0 10 9 97.0 11 10 112. 4 It was apparent that useful thermally stable PVC coatings can be produced using the stabilizers of the invention.