EP0000389B1 - Process for the preparation of polyurethane resins - Google Patents

Description

The present invention relates to a process for the production of polyurethane plastics, preferably foams, using novel catalysts having tertiary nitrogen atoms which are incorporated into the polyurethane and at the same time act as aging and light stabilizers.

Polyurethane foams with a wide variety of physical properties have been made for a long time by the known isocyanate polyaddition process from compounds having several active hydrogen atoms, in particular compounds containing hydroxyl and / or carboxyl groups, and polyisocyanates, with the use of water and / or blowing agents and, if appropriate, catalysts, emulsifiers and other additives produced on an industrial scale (Angew. Chem. A, 59 (1948), p. 257). With a suitable choice of components, either elastic or rigid foams or all products lying between these extremes are obtained.

Polyurethane foams are preferably produced from liquid starting components, the starting materials to be reacted with one another either being mixed together in a one-step process or else a pre-adduct containing NCO groups is prepared from a polyol and an excess of polyisocyanate, which then, e.g. is foamed by reaction with water.

Tertiary amines have proven themselves as catalysts in the production of polyurethane foams primarily because they both react the reaction between hydroxyl or. Accelerate carboxyl groups and NCO groups (urethane reaction) as well as the reaction between water and isocyanates (blowing reaction), whereby the speeds of the two reactions running side by side can also be coordinated with one another in the one-shot process.

In addition to the reactions already mentioned, additional crosslinking reactions take place during the foaming process, with the formation of allophanate, biuret and cyanurate structures.

In view of this multitude of reactions, it is necessary to choose the catalyst so that on the one hand the synchronous course of the reactions is ensured and on the other hand the catalyst is not fixed too early by incorporation into the foam or later accelerates the hydrolytic degradation of the finished foam. This problem has not yet been fully satisfactorily resolved. In addition, the unpleasant smell of many tertiary amines used in practice is disadvantageous. In addition, polyurethane foams tend to be present in the presence of the most commonly used amine catalysts, e.g. Dabco @ or bis (dialkylaminoalkyl) ethers (DOS 1 804 361 and US Pat. No. 3,330,782) on their own or also laminated with colored plastic films (for example PVC films) for yellowing or discoloration and blackening under thermal stress or exposure to light . The blackening of colored plastic films, as they are technically used to cover polyurethane foams, e.g. automotive seats, refrigerators and electrical appliances. These adverse effects block the polyurethane foams and polyurethane plastics in many other possible areas of application.

Surprisingly, catalysts have now been found which, on their own or in a mixture with known amine catalysts, prevent discoloration of foam-backed plastic films (e.g. PVC films) under thermal stress and / or exposure to light, as well as aging effects in the case of free-foamed polyurethane plastics.

• (a) Polyisocyanaten mit
• (b) Verbindungen mit mindestens 2 gegenüber Isocyanaten reaktionsfähigen Wasserstoffatomen, in Gegenwart von
• (c) tertiären Aminen, welche gegenüber Isocyanaten reaktionsfähige Wasser stoffatome aufweisen, als Katalysatoren, gegebenenfalls unter Mitverwendung von
• (d) Treibmitteln, Stabilisatoren und weiteren an sich bekannten Zusatzstoffen,

welches dadurch gekennzeichnet ist, daß als Komponente (c)

• (A) Verbindungen der allgemeinen Formel
  
  und/oder
  
  und/oder
  
  und/oder
  
  
  gegebenenfalls in Gemisch mit bis zu 97 Mol-%, bezogen auf Gesamtmenge an katalysator, an anderen tertiären Aminen (B) als Co-Katalysator, eingesetzt werden, wobei
• die Reste R unabhängig voneinander gegebenenfalls verzweigte Alkylgruppen mit 1-4 C-Atomen, vorzugsweise Methylgruppen, darstellen,
• die Zahlen n unabhängig voneinander für 2 oder 3, vorzugsweise für 3,
• die Zahlen m unabhängig voneinander für 2 oder 3, vorzugsweise für 2, und k für eine ganze Zahl zwischen 1 und 5 stehen.

The present invention relates to a method for producing optionally cellular polyurethane plastics by reacting

• (a) Polyisocyanates with
• (b) Compounds with at least 2 isocyanate-reactive hydrogen atoms, in the presence of
• (c) tertiary amines which have hydrogen atoms which are reactive toward isocyanates, as catalysts, optionally with the use of
• (d) blowing agents, stabilizers and other additives known per se,

which is characterized in that as component (c)

• (A) Compounds of the general formula
  
  and or
  
  and or
  
  and or
  
  
  optionally in a mixture with up to 97 mol%, based on the total amount of catalyst, of other tertiary amines (B) as co-catalyst, where
• the radicals R independently of one another are optionally branched alkyl groups with 1-4 C atoms, preferably methyl groups,
• the numbers n independently of one another for 2 or 3, preferably for 3,
• the numbers m independently of one another represent 2 or 3, preferably 2, and k represents an integer between 1 and 5.

FR-A 2 085 965 likewise describes polyurethane catalysts which, in addition to a tertiary nitrogen atom, have a group which is reactive toward isocyanates. These catalysts correspond to the general formula

in which the two radicals R independently represent alkyl radicals or together with the nitrogen atom represent a heterocyclic radical and R 'represents a divalent organic radical, preferably an alkylene group having 2 to 10 carbon atoms. These catalysts are preferably used in combination with triethylenediamine. It has been shown, however, that such catalyst combinations are unable to solve the above-described problem of discoloration of plastic foils laminated with polyurethane foam when subjected to thermal stress or exposure to light.

According to the invention, preferred catalysts (A) are compounds of the general formulas (1) and (2).

The catalysts characterized by the general formulas (1) to (4) have a special position compared to the tertiary amines previously used due to their stabilizing action against thermal and photochemical aging. This is probably due to the fact that despite their content of active hydrogen atoms - due to steric hindrance - they are only very slowly incorporated into the polyurethane during the foaming process. As a result, they can surprisingly develop their stabilizing effect at the phase interfaces.

und

wobei R und n die oben angegebene Bedeutung haben.In the process according to the invention, in addition to the compounds (A) of the general formulas (1) to (4), amine catalysts (B) known per se in an amount of 3 to 97 mol%, preferably 10 to 90 mol%, particularly preferably 30 up to 70 Mo 1%, based on the total amount of catalyst, are also used, for example tertiary amines containing ether groups according to US Pat. No. 3,330,782, DAS 1 030 558 or DOS 1 804 361 or the ether group-free catalysts comprising at least 4 tertiary nitrogen atoms DOS 2 624 527 and DOS 2 624 528. However, according to the invention, preferred co-catalysts (B) are compounds which, in addition to at least one tertiary nitrogen atom, contain at least one amide group, in particular one formamide group. Such acylated amines are described in detail in DOS 2 523 633. According to the invention, the formylation products of the compounds (A) of the general formulas (1) to (4) and the compounds are particularly preferred in this context

and

where R and n have the meaning given above.

Examples of catalysts or co-catalysts to be used according to the invention are the following tertiary amines:

The catalysts to be used according to the invention can be prepared in a manner known per se, for example in DAS 1 154 269, DOS 2 523 633 and in "Die Angewandte Makromolekulare Chemie" 34, pp. 111-132 (1973), and from F Möller in Houben - Weyl, Xl / 2 (pp. 27-29).

According to the invention, a total of 0.01-5% by weight, preferably 0.1-3% by weight, based on the entire reaction mixture, of catalyst is generally used.

Suitable starting components according to the invention are aliphatic, cycloaliphatic, araliphatic, aromatic and heterocyclic polyisocyanates, as described, for example, by W. Siefken in Justus Liebgs Annalen der Chemie, 562, pages 75 to 136, for example ethylene diisocyanate, 1,4 -Tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, 1,12-dodecane diisocyanate, cyclobutane-1,3-diisocyanate, cyclohexane-1,3- and -1,4-diisocyanate and any mixtures of these isomers, 1-isocyanato-3,3, 5-trimethyl-5-isocyanatomethyl-cyclohexane (DAS 1 202 785, American patent specification 3 401 190), 2,4- and 2,6-hexahydrotoluenediisocyanate and any mixtures of these isomers, hexahydro-1,3- and / or -1, 4-phenylene diisocyanate, perhydro-2,4'- and / or -4,4'-diphenylmethane diisocyanate, 1,3- and 1,4-phenylene diisocyanate, 2,4- and 2,6-tolylene diisocyanate and any mixtures of these isomers, diphenylmethane-2,4'- and / or -4,4'-diisocyanate, naphthylene - 1,5 - diisocya nat, triphenylmethane - 4,4 ', 4 "- triisocyanate, Polyphenyl-polymethylene-polyisocyanates, as obtained by aniline-formaldehyde condensation and subsequent phosgenation and described, for example, in British Patents 874430 and 848 671, m- and p-isocyanatophenyl-sulfonyl-isocyanates according to American Patent 3,454,606, perchlorinated Aryl polyisocyanates as described, for example, in German Patent Specification 1,157,601 (US Pat. No. 3,277,138), polyisocyanates containing carbodiimide groups, as described in German Patent 1,092,007 (US Pat. No. 3,152,162), diisocyanates as described in U.S. Patent 3,492,330 describes polyisocyanates containing allophanate groups, as described, for example, in British Patent 994,890, Belgian Patent 761,626 and published Dutch patent application 7,102,524, polyisocyanates containing isocyanurate groups, as described, for example, in the United States German patent specification 3 001 973, in German patent specifications 1 022 789, 1 222 067 and 1 027 394 as well as in German laid-open specifications 1 929 034 and 2 004 048, polyisocyanates containing urethane groups, as described, for example, in Belgian patent specification 752 261 or are described in the American patent specification 3 394 164, polyisocyanates containing acylated urea groups according to the German patent specification 1 230 778, polyisocyanates containing biuret groups, as described, for example, in German patent specification 1 101 394 (American patent specifications 3 124 605 and 3 201 372) and in British Patent 889,050, polyisocyanates prepared by telomerization reactions, such as are described, for example, in US Pat. No. 3,654,106, polyisocyanates containing ester groups, as described, for example, in British Patents 965,474 and 1,072,956, in American Patent 3,567 763 and in the German Patentsch rift 1 231 688, reaction products of the above-mentioned isocyanates with acetals according to German patent 1,072,385 and polymeric fatty acid residues containing polyisocyanates according to American patent 3,455,883.

It is also possible to use the distillation residues obtained in the industrial production of isocyanate and containing isocyanate groups, optionally dissolved in one or more of the aforementioned polyisocyanates. It is also possible to use any mixtures of the aforementioned polyisocyanates.

The technically easily accessible polyisocyanates, e.g. 2,4- and 2,6-tolylene diisocyanate as well as any mixtures of these isomers ("TDI"), polyphenyl polymethylene polyisocyanates, such as those produced by aniline-formaldehyde condensation and subsequent phosgenation ("crude MDI") and carbodiimide groups, Polyisocyanates containing urethane groups, allophanate groups, isocyanurate groups, urea groups or biuret groups ("modified polyisocyanates").

Starting components to be used according to the invention are furthermore compounds having at least two isocyanate-reactive hydrogen atoms with a molecular weight of generally 400-10,000. These include compounds containing amino groups, thiol groups or carboxyl groups, preferably polyhydroxyl compounds, in particular compounds containing two to eight hydroxyl groups, especially those from molecular weight 800 to 10,000, preferably 1000 to 6000, e.g. at least two, generally 2 to 8, but preferably 2 to 4, hydroxyl-containing polyesters, polyethers, polythioethers, polyacetals, polycarbonates and polyesteramides, as are known per se for the production of homogeneous and cellular polyurethanes.

The hydroxyl group-containing polyesters are e.g. Reaction products of polyhydric, preferably dihydric and optionally additionally trihydric alcohols with merhydric, preferably dihydric, carboxylic acids. Instead of the free polycarboxylic acids, the corresponding polycarboxylic acid anhydrides or corresponding polycarboxylic acid esters of lower alcohols or mixtures thereof can also be used to produce the polyesters. The polycarboxylic acids can be aliphatic, cycloaliphatic, aromatic and / or heterocyclic in nature and optionally, e.g. by halogen atoms, substituted and / or unsaturated.

Examples of these include: succinic acid, adipic acid, cork acid, azelaic acid, sebacic acid, phthalic acid, isophthalic acid, trimellitic acid, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, tetrachlorophthalic anhydride, malefic acid, malefic acid, malefic acid, malefic acid, anhydride, maleic acid, malefic acid, fatty acid, malefic acid, anhydrous acid, malic acid, malefic acid, fatty acid, malefic acid, fatty acid, malefic acid, fatty acid, malefic acid such as, with monomeric fatty acids, terephthalic acid dimethyl ester and terephthalic acid - bis - glycol ester. Examples of polyhydric alcohols include ethylene glycol, propylene glycol - (1,2) and - (1,3), butylene glycol - (1,4) and - (2,3), hexanediol - (1,6), octanediol - (1, 8), neopentyl glycol, cyclohexanedimethanol (1,4 - bis - hydroxymethylcyclohexane), 2 - methyl - 1,3 - propanediol, glycerin, trimethylol propane, hexanetriol - (1,2,6), butanetriol - (1,2,4 ), Trimethylolethane, pentaerythritol, quinite, mannitol and sorbitol, methylglycoside, also daithylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycols, dipropylene glycol, polypropylene glycols, dibutylene glycol and polybutylene glycols. The polyesters may have a proportion of terminal carboxyl groups. Polyesters of lactones, for example _E- caprolactone or hydroxycarboxylic acids, for example co-hydroxycaproic acid, can also be used.

The at least two, generally two to eight, preferably two to three, hydroxyl-containing polyethers which are suitable according to the invention are also of the type known per se and are obtained, for example, by polymerizing epoxides such as ethylene oxide, propylene oxide, butylene oxide, tetrahydrofuran, styrene oxide or Epichlorohydrin with itself, for example in the presence of BF ₃ , or by addition of these epoxides, if appropriate in a mixture or in succession, to starting components with reactive hydrogen atoms such as water, alcohols, ammonia or amines, for example ethylene glycol, propylene glycol - (1,3) or - (1,2), trimethylolpropane, 4,4'-dihydroxy-diphenylpropane, aniline, ethanolamine or ethylenediamine. Sucrose polyethers, such as are described, for example, in German publications 1 176 358 and 1 064 938, are also suitable according to the invention. In many cases, those polyethers are preferred which predominantly (up to 90% by weight, based on all OH groups present in the polyether) have primary OH groups. Polyethers modified by vinyl polymers, such as those formed by polymerizing styrene and acrylonitrile in the presence of polyethers (American patents 3383 351, 3 304273, 3 523 093, 3 110695, German patent 1 152 536), are also suitable, as are OH groups containing polybutadienes.

Among the polythioethers, the condensation products of thiodiglycol with itself and / or with other glycols, dicarboxylic acids, formaldehyde, aminocarboxylic acids or amino alcohols should be mentioned in particular. Depending on the co-components, the products are polythio ether, polythio ether ester or polythio ether ester amide.

As polyacetals e.g. the compounds which can be prepared from glycols, such as diethylene glycol, triethylene glycol, 4,4'-dioxethoxydiphenyldimethylmethane, hexanediol and formaldehyde, are suitable. Polyacetals suitable according to the invention can also be prepared by polymerizing cyclic acetals.

Suitable polycarbonates containing hydroxyl groups are those of the type known per se, which e.g. by reacting diols such as propanediol - (1,3), butanediol - (1,4) and / or hexanediol - (1,6), diethylene glycol, triethylene glycol or tetraethylene glycol with diaryl carbonates, e.g. Diphenyl carbonate, or phosgene can be produced.

The polyester amides and polyamides include e.g. the predominantly linear condensates obtained from polyvalent saturated and unsaturated carboxylic acids or their anhydrides and polyvalent saturated and unsaturated amino alcohols, diamines, polyamines and their mixtures.

Polyhydroxyl compounds already containing urethane or urea groups and optionally modified natural polyols such as castor oil, carbohydrates or starch can also be used. Addition products of alkylene oxides with phenol-formaldehyde resins or with urea-formaldehyde resins can also be used in accordance with the invention.

Representatives of these compounds to be used according to the invention are e.g. in High Polymers, Vol. XVI, "Polyurethanes, Chemistry and Technology", written by Saunders-Frisch, Interscience Publishers, New York, London, Volume I, 1962, pages 32-42 and pages 44-54 and volume 11, 1964, Pages 5-6 and 198-199, as well as in the plastic manual, volume Vii, Vieweg-Höchtlen, Carl-Hanser-Verlag, Munich, 1966, e.g. on pages 45-71.

Of course, mixtures of the above-mentioned compounds with at least two isocyanate-reactive hydrogen atoms with a molecular weight of 400-10,000, e.g. Mixtures of polyethers and polyesters can be used.

Compounds with at least two isocyanate-reactive hydrogen atoms with a molecular weight of 32-400 are also suitable as starting components to be used according to the invention, if appropriate in a mixture with the higher molecular weight compounds mentioned. In this case too, this means hydroxyl groups and / or amino groups and / or thiol groups and / or carboxyl group-containing compounds, preferably compounds containing hydrocyclic groups and / or amino groups, which serve as chain extenders or crosslinking agents. These compounds generally have 2 to 8 isocyanate-reactive hydrogen atoms, preferably 2 or 3 reactive hydrogen atoms.

Examples of such compounds are: ethylene glycol, (1,2) and - (1,3) propylene glycol, (1,4) and - (2,3) butylene glycol, (1,5) pentanediol, hexanediol (1,6), octanedioi- (1,8), neopentyl glycol, 1,4-bis-hydroxymethyl-cyclohexane, 2-methyl-1,3-propanediol, glycerin, trimethylolpropane, hexanetriol- (1,2,6), Trimethylolethane, pentaerythritol, quinite, mannitol and sorbitol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycols with a molecular weight up to 400, dipropylene glycol, polypropylene glycols with a molecular weight up to 400, dibutylene glycol, polybutylene glycols 4,4'-diol'-diol, up to 400 hydroxymethyl hydroquinone, ethanolamine, diethanolamine, triethanolamine, 3-aminopropanol, ethylenediamine, 1,3-diaminopropane, 1-mercapto-3-aminopropane, 4-hydroxy- or -amino-phthalic acid, succinic acid adipic acid, hydrazine, N, N'- Dimethylhydrazine, 4,4'-diaminodiphenylmethane, toluenediamine, methylenebis-chloroaniline, methylene-bis-anthranils diaminobenzoic acid ester and the isomeric chlorophenylenediamines.

In this case, too, mixtures of different compounds with at least two hydrogen atoms reactive towards isocyanates with a molecular weight of 32-400 can be used.

According to the invention, however, polyhydroxyl compounds can also be used in which high molecular weight polyadducts or polycondensates are contained in finely dispersed or dissolved form. Such modified polyhydroxyl compounds are obtained if polyaddition reactions (e.g. reactions between polyisocyanates and amino-functional compounds) or polycondensation reactions (e.g. between formaldehyde and phenols and / or amines) are carried out directly in situ in the above-mentioned compounds containing hydroxyl groups. Such methods are described, for example, in German Auslegeschrift 1 168 075 and 1 260 142, and German Offenlegungsschriften 2,324,134, 2,423,984, 2,512,385, 2,513,815, 2,550,796, 2,550,797, 2,550,833 and 2,550 862. However, it is also possible to mix a finished aqueous polymer dispersion with a polyhydroxyl compound in accordance with US Pat. No. 3,869,413 or German Offenlegungsschrift 2,550,860 and then remove the water from the mixture.

When using modified polyhydroxyl compounds of the type mentioned above as the starting component in the polyisocyanate polyaddition process, polyurethane plastics with significantly improved mechanical properties are produced in many cases.

According to the invention, water and / or volatile organic substances can also be used as blowing agents. Organic foaming agents include Acetone, ethyl acetate, halogen-substituted alkanes such as methylene chloride, chloroform, ethylidene chloride, vinylidene chloride, monofluorotrichloromethane, chlorodifluoromethane, dichlorodifluoromethane, butane, hexane, heptane or diethyl ether are also suitable. A blowing effect can also be achieved by adding compounds which decompose at temperatures above room temperature with the elimination of gases, for example nitrogen. Azo compounds such as azoisobutyronitrile can be achieved. Further examples of propellants as well as details on the use of propellants can be found in the Kunststoff-Handbuch, Volume VII, published by Vieweg and Höchtlen, Carl-Hanser-Verlag, Munich 1966, e.g. on pages 108 and 109, 453 to 455 and 507 to 510.

According to the invention, other catalysts known per se can of course also be used, e.g. tertiary amines such as triethylamine, tributylamine, N-methylmorpholine, N-ethylmorpholine, N-cocomorpholine, N, N, N ', N'-tetramethyl-ethylenediamine, 1,4-diaza-bicyclo- (2,2,2 ) octane, N-methyl-N'-dimethylaminoethyl piperazine, N, N-dimethylbenzylamine, bis (N, N-diethylaminoethyl) adipate, N, N-diethylbenzylamine, pentamethyl-diethylenetriamine, N, N-dimethylcyclohexylamine , N, N, N ', N'-tetramethyl-1,3-butanediamine, N, N-dimethyl-ß-phenylethylamine, 1,2-dimethylimidazole and 2-methylimidazole. Mannich bases known per se from secondary amines such as dimethylamine and aldehydes, preferably formaldehyde, or ketones such as acetone, methyl ethyl ketone or cyclohexanone and phenols such as phenol, nonylphenol or bisphenol are also suitable as additional catalysts.

Tertiary amines which have hydrogen atoms active against isocyanate groups as catalysts are e.g. Triethanolamine, triisopropanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, N, N-dimethylethanolamine, and their reaction products with alkylene oxides, such as propylene oxide and / or ethylene oxide.

Silaamines with carbon-silicon bonds, such as those e.g. in German Patent 1,229,290 (corresponding to American Patent 3620984) are in question, e.g. 2,2,4-trimethyl-2-silamorpholine and 1,3-diethylaminomethyltetramethyl-disiloxane.

Suitable additional catalysts are also nitrogenous bases such as tetraalkylammonium hydroxides, alkali metal hydroxides such as sodium hydroxide, alkali phenolates such as sodium phenolate or alkali metal alcoholates such as sodium methylate. Hexahydrotriazines can also be used as catalysts.

According to the invention, organic metal compounds, in particular organic tin compounds, can also be used as catalysts.

Preferred organic tin compounds are tin (11) salts of carboxylic acids such as tin (ii) acetate, tin (II) octoate, tin (II) ethylhexoate and tin (II) laurate and the tin (IV) compounds, e.g. Dibutyltin oxide, dibutyltin dichloride, dibutyltin diacetate, dibutyltin dilaurate, dibutyltin maleate or dioctyltin diacetate can be considered. Of course, all of the above catalysts can be used as mixtures.

Further representatives of catalysts which may be used according to the invention and details of the mode of action of the catalysts are in the Plastic Handbuck, Volume VII, edited by Vieweg and Höchtlen, Carl-Hanser-Verlag, Munich 1966, e.g. described on pages 96 to 102.

According to the invention, surface-active additives such as emulsifiers and foam stabilizers can also be used.

Suitable emulsifiers are, for example, the sodium salts of castor oil sulfonates or salts of fatty acids with amines such as oleic acid diethylamine or stearic acid diethanolamine. Also alkali or ammonium salts of sulfonic acids such as dodecylbenzenesulonic acid or dinaphthyl methanedisulfonic acid or of fatty acids such as ricinoleic acid or of polymeric fatty acids can also be used as surface-active additives.

Polyether siloxanes, especially water-soluble representatives, are particularly suitable as foam stabilizers. These compounds are generally designed so that a copolymer of ethylene oxide and propylene oxide is linked to a polydimethylsiloxane residue. Such foam stabilizers are e.g. in U.S. Patents 2,834,748, 2,917,480, and 3,629,308.

According to the invention, reaction retarders, e.g. acidic substances such as hydrochloric acid or organic acid halides, further cell regulators of the type known per se such as paraffins or fatty alcohols or dimethylpolysiloxanes as well as pigments or dyes and flame retardants of the type known per se, e.g. tris-chloroethyl phosphate, tricresyl phosphate or ammonium phosphate and polyphosphate, also stabilizers against aging and weather influences, plasticizers and fungistatic and bacteriostatic substances and fillers such as barium sulfate, diatomaceous earth, carbon black or sludge chalk are also used.

Further examples of surface-active additives and foam stabilizers to be used according to the invention, as well as cell regulators, reaction retarders, stabilizers, flame-retardant substances, plasticizers, dyes and fillers, as well as fungistatic and bacteriostatic substances, and details on the use and action of these additives are given in the Plastics Manual, Volume VII by Vieweg and Höchtlen, Carl-Hanser-Verlag, Munich 1966, e.g. described on pages 103 to 113.

According to the invention, the reaction components are reacted according to the one-step process, the prepolymer process or the semi-prepolymer process, which are known per se, machine equipment often being used, e.g. those described in U.S. Patent 2,764,565. Details on processing devices that are also suitable according to the invention are given in the plastics manual, volume VII, published by Vieweg and Höchtlen, Carl-Hanser-Verlag, Munich 1966, e.g. described on pages 121 to 205.

In foam production, foaming is often carried out in molds according to the invention. The reaction mixture is introduced into a mold. Metal is used as the molding material, e.g. Aluminum, or plastic, e.g. Opoxy resin, in question. The foamable reaction mixture foams in the mold and forms the shaped body. The foam molding can be carried out so that the molded part has a cell structure on its surface, but it can also be carried out so that the molded part has a compact skin and a cellular core. According to the invention, one can proceed in this connection in such a way that so much foamable reaction mixture is introduced into the mold that the foam formed just fills the mold. However, it is also possible to work by adding more foamable reaction mixture to the mold than is necessary to fill the interior of the mold with foam. In the latter case, "overcharging" is used; such a procedure is e.g. known from U.S. Patents 3,178,490 and 3,182,104.

In the case of mold foaming, "external release agents" known per se, such as silicone oils, are often used. But you can also use so-called "internal release agents", optionally in a mixture with external release agents, such as those e.g. have become known from German Offenlegungsschriften 2 121 670 and 2 307 589.

Cold-curing foams can also be produced according to the invention (cf. British patent specification 1 162517, German patent application specification 2 153 086).

Of course, foams can also be produced by block foaming or by the double conveyor belt process known per se.

The process products are preferably flexible, semi-flexible or hard polyurethane foams. You will find the known use for such products, e.g. as mattresses and upholstery material in the furniture and automotive industry, also for the manufacture of fittings such as are used in the automotive industry and finally as insulation and means for heat or cold insulation, e.g. in the construction sector or in the refrigerated furniture industry.

The following examples illustrate the process according to the invention without limiting it. Unless otherwise noted, quantities are to be understood as parts by weight or percentages by weight.

example 1

100 g of a mixture of 100 parts of a copolyether started on trimethylolpropane and having an average molecular weight of 4800 and consisting of 87% propylene oxide and 13% ethylene oxide

2 parts of triethanolamine,

2.3 parts of water and

1.2 parts of a mixture of equal parts by weight of bis (dimethylamino-n-propyl) amine and N-methyl-N '- (3-formylaminopropyl) piperazine
are intensively mixed with 46 g of the phosgenation product of a technical aniline-formaldehyde condensate (viscosity: 200 cP at 25 ° C). The foam thus obtained is partially covered with a green-colored PVC film and stored at 100 ° C. in a drying cabinet. The lightfastness of the free-foamed product is determined separately based on DIN 54 004.

• Beispiel 1 wird wiederholt, jedoch unter Verwendung von 1,2 Teilen Tetramethyl-äthylendiamin anstelle des erfindungsgemäßen Katalysatorgemisches.

Comparative Example 1 a:

• Example 1 is repeated, but using 1.2 parts of tetramethylethylenediamine instead of the catalyst mixture according to the invention.

• Beispiel 1 wird wiederholt, jedoch unter Verwendung von 1,2 Teilen N-Dimethylamino-N'-(2-dimethylamino-propionyl)-aminal anstelle des erfindungsgemäßen Katalysatorgemisches.

Comparative Example 1b:

• Example 1 is repeated, but using 1.2 parts of N-dimethylamino-N '- (2-dimethylamino-propionyl) aminal instead of the catalyst mixture according to the invention.

• Beispiel 1 wird wiederholt, jedoch unter Verwendung von 1,2 Teilen eines Gemisches von gleichen Teilen Triäthylendiamin und 3-Dimethylamino-1-propylamin anstelle des erfindungsgemäßen Katalysatorgemisches.

Comparative Example 1c

• Example 1 is repeated, but using 1.2 parts of a mixture of equal parts of triethylenediamine and 3-dimethylamino-1-propylamine instead of the catalyst mixture according to the invention.

The results of the tests are summarized in the following table.

Example 2

The procedure is as described in Example 1, but 1.2 parts of bis (3-dimethylamino-n-propyl) amine are used.

The following results are obtained:

Example 3

The procedure is as described in Example 1, but with 1.2 parts of N, N-bis (3-dimethylamino-n-propyl) propylene diamine.

Example 4

The procedure is as described in Example 1, but with 1.2 parts of a mixture of equal parts by weight of bis- (3-dimethylamino-n-propyl) -amine and 1-N-formyl-4-N- (2-formylamino) -ethyl) -piperazine worked.

The following results are obtained:

Example 5

The procedure is as described in Example 1, but 1.2 parts of a mixture of equal parts by weight of bis- (3-dimethylamino-n-propyl) amine and methyl-bis- (3-N-formylamino propyl) amine are used.

The following result of the thermal and photochemical aging tests is obtained:

Example 6

The procedure is as described in Example 1, but 1.2 parts of a mixture of equal parts by weight of bis- (3-dimethylamino-n-propyl) amine and dimethylamino-n-propyl-formamide are used. The following results are obtained:

Claims (6)

1. et/ou

   

   R et n ayant les definitions données dans la revendication 1.
2. 5. Procédé suivant l'une quelconque des revendications 1 à 4, caractérisé en ce que R est un groupe méthyle, m est égal à 2 et n est égal à 3.
3. 1. Process for the production of optionally cellular polyurethane resins by the reaction of:

   (a) polyisocyanates, with

   (b) compounds having at least 2 isocyanate reactive hydrogen atoms, in the presence of

   (c) tertiary amines containing isocyanate reactive hydrogen atoms, as catalysts, optionally with the addition of

   (d) blowing agents, stabilizers and other known additives; characterised in that the compounds used as a component (c) are:

   (A) compounds of the general formula

   

   and/or

   

   and/or

   

   and /or

   

   optionally as mixtures with up to 97 mol%, based on the whole catalyst mixture, or other tertiary amines (B), in which formulae:

   the radicals R represent, independently of each other, optionally branched-chain alkyl groups having from 1 to 4 carbon atoms,

   the figures n represent, independently of each other, 2 or 3;

   the figures m represent, independently of each other, 2 or 3; and K represents an integer of from 1 to 5.
4. 2. Process according to claim 1, characterised in that from 30 to 70 mol% based on the whole catalyst mixture, of co-catalysts (B) are used,
5. 3. Process according to claim 1 or 2, characterised in that the compounds used as co-catalysts (B) have at least one tertiary nitrogen atom and at least one amide group.
6. 4. Process according to claim 3, characterised in that the compounds used as co-catalysts (B) are formylation products of the compounds (A) of the general formulae (1) to (4) in claim 1 and/or the compounds:

   

   

   

   and /or

   

   wherein R and n are as defined in claim 1.

   5. Process according to claims 1 to 4 characterised in that:

   R represents a methyl group,

   m represents 2 and

   n represents 3.