EP3947505A1 - Methods for producing flame-retardant pur/pir foam materials - Google Patents

Abstract

The invention relates to flame-retardant polyurethane foam materials or polyurethane/polyisocyanurate foam materials (also referred to individually or collectively as "PUR/PIR foam materials" below) and to methods for producing PUR/PIR foam materials by reacting a reaction mixture containing A1 an isocyanate-reactive component, A2 a propellant, A3 a catalyzer, A4 optionally an additive, and A5 a flame retardant with B an isocyanate component, wherein the production is carried out using an index of 80 to 600. The invention is characterized in that the flame retardant A5 contains diethyl (hydroxymethyl)phosphonate and optionally the dimer thereof as component A5.1.

Description

Process for the production of flame-retardant PUR- / PIR-Sdiaiimstoffe

The present invention relates to flame-retardant polyurethane foams or polyurethane / polyisocyanurate foams (hereinafter referred to individually or collectively as “PUR / PIR foams”) containing dibutylhydroxymethylphosphonate, as well as processes for producing PUR / PIR foams.

Like all organic polymers, PUR / PIR foams are also flammable, whereby the large surface area per unit of mass in foams intensifies this behavior. PUR / PIR foams are often used as insulation materials, for example as insulation in the construction industry. In many areas of application of PUR / PIR foams, fire protection equipment through added flame retardants is therefore necessary.

Halogen-containing compounds and nitrogen and phosphorus compounds are preferably used as flame retardants. Compounds that contain halogens and low-valent phosphorus compounds are typical representatives of flame retardants that suffocate flames. Higher valent phosphorus compounds are supposed to cause catalytic cleavage of the polyurethanes and thereby lead to the formation of a solid, polyphosphate-containing, charred surface. This intumescent layer protects the material from further combustion (G.W. Becker, D. Braun: Polyurethane. In: G. Oertel (Ed.), Kunststoff Handbuch, Munich, Carl Hanser Verlag, 1983, 2, 104-1-5).

A disadvantage, especially of the halogen-containing representatives of these classes, is that they are persistent and relatively volatile and can thus migrate out of the foam (JC Quagliano, VM Wittemberg, ICG Garcia: Recent Advances on the Utilization of Nanoclays and Organophosphorus Compounds in Polyurethane Foams for Increasing Flame Retardancy. In: J. Njuguna (Ed.), Structural Nanocomposites, Engineering Materials, Berlin Heidelberg, Springer Verlag, 2013, 1, 249-258) and when used in the combustion process, corrosive hydrohalic acid is formed.

Due to the increasing spread of organic halogen compounds, some of which are harmful to health in the environment, interest is directed towards halogen-free alternatives, e.g. on halogen-free phosphate esters and phosphite esters (SV Eevchik, ED Weil: A Review of Recent Progress in Phosphorus-based Flame Retardants, J. Fire Sci., 2006, 24, 345-364, M. M Velencoso et al. Angewandte Chemie Int. Ed . 2018, 57, 10450-10467) and on red phosphorus.

The most widespread are PUR and PIR foams that are made flame-retardant with organic phosphates such as tris (2-chloroisopropyl) phosphate (TCPP) and triethyl phosphate (TEP). Organic phosphonic acid esters such as dimethylpropane phosphonate (DMPP, DE 44 18 307 Al) or diethylethylphosphonate (DEEP, US 5,268,393) and others (WO 2006/108833 A1 and EP 1 142 940 A2) are described as halogen-free flame retardants for rigid foams based on isocyanate. Solid ammonium polyphosphate (APP) has also already been used as a flame retardant (US 2014/066532 A1 and US 5,470,891); formulations on this basis are not storage-stable due to the tendency of APP to sediment.

But these halogen-free alternatives also have disadvantages: In some cases they are sensitive to hydrolysis under the alkaline conditions typical for PUR / PIR foam systems, or their effectiveness is not satisfactory. TEP is a strong plasticizer and, given the quantities required for adequate flame retardancy, often leads to insufficient compressive strength of foams. Red phosphorus has disadvantages, e.g. with regard to rapid absorption of moisture and rapid oxidation, which leads to a loss of flame retardancy and possibly the formation of toxic phosphines, and is also prone to powder explosions. Often times, red phosphorus is microencapsulated to eliminate these problems. (F. Chen, Y.-Z. Wang: A review on flame retardant technology in China. Part 1: development of flame retardants, Polym. Adv. Technol., 2010, 21, 1-26).

US 3,385,801 and WO 2010/080425 disclose the production of dialkyl-a-hydroxyalkylphosphonates and their use as flame retardants. No information is given on the influence of the dialkyl-a-hydroxyalkylphosphonates on the mechanical properties, especially the elasticity and the toughness when subjected to tensile loading of polyurethane foams.

The object of the present invention is to enable the production of PUR / PIR foams with halogen-free flame retardants, the PUR / PIR foams having good flame retardancy and improved mechanical properties, preferably none of them classified as carcinogenic, mutagenic or toxic to reproduction Substances are used.

This object could be achieved by the use according to the invention of a component A5.1 as a flame retardant in the production of PUR / PIR foams.

The invention relates to a process for producing PUR / PIR foams by converting a reaction mixture containing them

Al is an isocyanate-reactive component

A2 propellant

A3 catalyst A4 if necessary with additive A5 flame retardant

B of an isocyanate component, the production being carried out with an index of 80 to 600, characterized in that the flame retardant A5 contains dibutylhydroxymethylphosphonate and optionally its dimer as component A5.1.

Surprisingly, it was found that the PUR / PIR foams according to the invention comprising a component A5.1 have good flame retardancy despite low phosphorus contents. In a particular embodiment, the kinetic properties of the formulations according to the invention for the production of PUR / PIR foams are also improved. In a further particular embodiment, the mechanical properties, such as tensile strength, elongation at break, toughness and open-cell content of the PUR / PIR foams are also improved.

At least one compound selected from the group consisting of polyether polyols, polyester polyols, polyether ester polyols, polycarbonate polyols and polyether-polycarbonate polyols is used as the isocyanate-reactive component Al. Polyester polyols and / or polyether polyols are preferred. The isocyanate-reactive component Al can preferably have a hydroxyl number between 25 to 800 mg KOH / g, in particular 50 to 500 mg KOH / g, particularly preferably 100 to 400 mg KOH / g and very particularly preferably 100 to 300 mg KOH / g. The individual polyol component preferably has a number average molecular weight of 120 g / mol to 6000 g / mol, in particular 400 g / mol to 2000 g / mol and particularly preferably 400 g / mol to 700 g / mol.

The number average molar mass M _n (also: molecular weight) is determined in the context of this invention by gel permeation chromatography according to DIN 55672-1 (August 2007).

The OH number (also: hydroxyl number) indicates the OH number in the case of an individually added polyol. Information on the OH number for mixtures relates to the number-average OH number of the mixture, calculated from the OH numbers of the individual components in their respective molar proportions. The OH number indicates the amount of potassium hydroxide in milligrams, which is equivalent to the amount of acetic acid bound during acetylation of one gram of substance. In the context of the present invention, the OH number is determined in accordance with the DIN 53240-1 standard (June 2013). In the context of the present invention, “functionality” denotes the theoretical average functionality calculated from the known starting materials and their quantitative ratios (number of functions in the molecule that are reactive toward isocyanates or toward polyols).

The equivalent weight indicates the ratio of the number average molecular mass and the functionality of the isocyanate-reactive component. The equivalent weight data for mixtures are calculated from equivalent weights of the individual components in their respective molar proportions and relate to the number-average equivalent weight of the mixture.

The polyester polyols of component Al can, for example, polycondensates of polyhydric alcohols, preferably diols, with 2 to 12 carbon atoms, preferably with 2 to 6 carbon atoms, and polycarboxylic acids, such as e.g. Di-, tri- or even tetracarboxylic acids, or hydroxycarboxylic acids or factons, aromatic dicarboxylic acids or mixtures of aromatic and aliphatic dicarboxylic acids are preferably used. Instead of the free polycarboxylic acids, it is also possible to use the corresponding polycarboxylic acid anhydrides or corresponding polycarboxylic acid esters of lower alcohols to prepare the polyesters. Phthalic anhydride, terephthalic acid and / or isophthalic acid are preferably used.

Particularly suitable carboxylic acids are: succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, decanedicarboxylic acid, tetrahydrophthalic acid, hexahydrophthalic acid, cyclohexanedicarboxylic acid, tetrachlorophthalic acid, itaconic acid, malonic acid, itaconic acid, malonic acid, 2,2-dimethylsuccinic acid, 3,3-methyl-succinic acid, dicarboxylic acid , Dodecanedioic acid, endomethylenetetrahydrophthalic acid, dimer fatty acid, trimer fatty acid, citric acid, trimellitic acid, benzoic acid, trimellitic acid, maleic acid, fumaric acid, phthalic acid, isophthalic acid and terephthalic acid. It is also possible to use derivatives of these carboxylic acids, for example dimethyl terephthalate. The carboxylic acids can be used either individually or as a mixture. The carboxylic acids used are preferably adipic acid, sebacic acid and / or succinic acid, particularly preferably adipic acid and / or succinic acid.

Hydroxycarboxylic acids which can also be used as reactants in the production of a polyester polyol with terminal hydroxyl groups are, for example, hydroxycaproic acid, hydroxybutyric acid, hydroxydecanoic acid, hydroxystearic acid and the like. Suitable factons include caprolactone, propiolactone, butyrolactone and homologues.

Bio-based starting materials and / or their derivatives are particularly suitable for the production of polyester polyols, such as B. castor oil, polyhydroxy fatty acids, ricinoleic acid, Hydroxyl-modified oils, grape seed oil, black caraway seed oil, pumpkin seed oil, borage seed oil, soybean oil, wheat seed oil, rapeseed oil, sunflower seed oil, peanut oil, apricot kernel oil, pistachio oil, almond oil, olive oil, macadamia nut oil, hazelnut oil, wild rose oil, sea buckthorn oil, hazelnut oil, wild rose oil, sea buckthorn oil Walnut oil, fatty acids, hydroxyl-modified and epoxidized fatty acids and fatty acid esters, for example based on myristoleic acid, palmitoleic acid, oleic acid, vaccenic acid, petroselic acid, gadoleic acid, erucic acid, nervonic acid, finoleic acid, alpha- and gamma-finolenic acid, and cupervanodonic acid, stearidonic acid, arachidonic acid. Esters of ricinoleic acid with polyfunctional alcohols, for example glycerol, are particularly preferred. The use of mixtures of such bio-based acids with other carboxylic acids, for example phthalic acids, is also preferred.

Examples of suitable diols are ethylene glycol, butylene glycol, diethylene glycol, triethylene glycol, polyalkylene glycols such as polyethylene glycol, furthermore 1,2-propanediol, 1,3-propanediol, cyclohexanedimethanol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol and Isomers, neopentyl glycol or neopentyl glycol hydroxypivalate. Ethylene glycol, diethylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol or mixtures of at least two of the diols mentioned, in particular mixtures of 1,4-butanediol, 1,5-pentanediol and 1, are preferably used 6-hexanediol.

In addition, polyols such as trimethylolpropane, glycerol, erythritol, pentaerythritol, trimethylolbenzene or trishydroxyethyl isocyanurate can also be used, glycerol and trimethylolpropane being preferred.

Monohydric alkanols can also be used.

Polyether polyols used according to the invention are obtained by production methods known to the person skilled in the art, such as, for example, by anionic polymerization of one or more alkylene oxides having 2 to 4 carbon atoms with alkali hydroxides, such as sodium or potassium hydroxide, alkali alcoholates, such as sodium methylate, sodium or potassium ethylate or potassium isopropylate, or aminic alkoxylation Catalysts, such as dimethylethanolamine (DMEOA), imidazole and / or imidazole derivatives, using at least one starter molecule which contains 2 to 8, preferably 2 to 6, reactive hydrogen atoms bonded.

Suitable alkylene oxides are, for example, tetrahydrofuran, 1,3-propylene oxide, 1,2- or 2,3-butylene oxide, styrene oxide and preferably ethylene oxide and 1,2-propylene oxide. The alkylene oxides can be used individually, alternately in succession or as mixtures. Preferred alkylene oxides are propylene oxide and ethylene oxide, and ethylene oxide is particularly preferred. The alkylene oxides can be converted in combination with CO2. As starter molecules, for example: water, organic dicarboxylic acids such as succinic acid, adipic acid, phthalic acid and terephthalic acid, aliphatic and aromatic, optionally N-mono-, N, N- and N, N'-dialkyl-substituted diamines with 1 to 4 carbon atoms in the alkyl radical such as optionally mono- and dialkyl-substituted ethylenediamine, diethylenetriamine, triethylenetetramine, 1,3-propylenediamine, 1,3- or 1,4-butylenediamine, 1,2-, 1,3-, 1,4-, 1,5- and 1,6-hexamethylenediamine, phenylenediamines, 2,3-, 2,4- and 2,6-tolylenediamine, and 2,2'-, 2,4'- and 4,4'-diaminodiphenylmethane.

Preference is given to using two or polyhydric alcohols such as ethanediol, 1,2- and 1,3-propanediol, diethylene glycol, dipropylene glycol, 1,4-butanediol, 1,6-hexanediol, triethanolamine, bisphenols, glycerol, trimethylolpropane, pentaerythritol, sorbitol and Sucrose.

Polycarbonate polyols which can be used are polycarbonates containing hydroxyl groups, for example polycarbonate diols. These arise in the reaction of carbonic acid derivatives, such as diphenyl carbonate, dimethyl carbonate or phosgene, with polyols, preferably diols.

Examples of such diols are ethylene glycol, 1,2- and 1,3-propanediol, 1,3- and 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, neopentyl glycol, 1,4-bishydroxymethylcyclohexane, 2- Methyl-1,3-propanediol, 2,2,4-trimethylpentanediol-1,3, dipropylene glycol, polypropylene glycols, dibutylene glycol, polybutylene glycols, bisphenols and lactone-modified diols of the type mentioned above.

Instead of or in addition to pure polycarbonate diols, it is also possible to use polyether-polycarbonate diols, which are obtainable, for example, by copolymerizing alkylene oxides, such as propylene oxide, with CO 2.

Polyetherester polyols which can be used are those compounds which contain ether groups, ester groups and OH groups. Organic dicarboxylic acids with up to 12 carbon atoms are suitable for the preparation of the polyetherester polyols, preferably aliphatic dicarboxylic acids with 4 to 6 carbon atoms or aromatic dicarboxylic acids, which are used individually or in a mixture. Examples are suberic acid, azelaic acid, decanedicarboxylic acid, furandicarboxylic acid, maleic acid, malonic acid, phthalic acid, pimelic acid and sebacic acid, and in particular glutaric acid, fumaric acid, succinic acid, adipic acid, phthalic acid, terephthalic acid and isoterephthalic acid. In addition to organic dicarboxylic acids, derivatives of these acids, for example their anhydrides and their esters and half esters with low molecular weight, monofunctional alcohols having 1 to 4 carbon atoms, can also be used. The proportional use of the bio-based starting materials mentioned above, in particular of fatty acids or fatty acid derivatives (oleic acid, soybean oil, etc.) is also possible and can have advantages, for example in With regard to the storage stability of the polyol formulation, dimensional stability, fire behavior and compressive strength of the foams.

Polyether polyols obtained by alkoxylating starter molecules such as polyhydric alcohols are used as a further component for the production of the polyether ester polyols. The starter molecules are at least difunctional, but can optionally also contain proportions of higher-functional, in particular trifunctional, starter molecules.

Starter molecules are, for example, diols such as 1,2-ethanediol, 1,3-propanediol, 1,2-propanediol, 1,4-butanediol, 1,5-pentenediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,10-decanediol, 2-methyl-1,3-propanediol, 2,2-dimethyl-1,3-propanediol, 3-methyl-1,5-pentanediol, 2-butyl-2-ethyl-l, 3-propanediol, 2-butene-l, 4-diol and 2-butyne-l, 4-diol, ether diols such as diethylene glycol, triethylene glycol, tetraethylene glycol, dibutylene glycol, tributylene glycol, tetrabutylene glycol, dihexylene glycol, Trihexylene glycol, tetrahexylene glycol and oligomer mixtures of alkylene glycols such as diethylene glycol. Starter molecules with functionalities other than OH can also be used alone or in a mixture.

In addition to the diols, compounds with more than 2 Zerewitinoff-active hydrogens, especially with number-average functionalities from 3 to 8, in particular from 3 to 6, for example 1,1,1-trimethylolpropane, triethanolamine, can also be used as starter molecules for the production of the polyethers , Glycerine, sorbitan and pentaerythritol as well as polyethylene oxide polyols started on triols or tetraoene.

Polyetherester polyols can also be prepared by alkoxylation, in particular ethoxylation and / or propoxylation, of reaction products obtained by reacting organic dicarboxylic acids and their derivatives and components with Zerewitinoff-active hydrogens, especially diols and polyols. As derivatives of these acids, for example, their anhydrides can be used, such as phthalic anhydride.

Production processes for the polyols are described, for example, by Ionescu in “Chemistry and Technology of Polyols for Polyurethanes”, Rapra Technology Limited, Shawbury 2005, page 55 ff. (Chapter 4: Oligo- Polyols for Elastic Polyurethanes), page 263 ff. (Ch . 8: Polyester Polyols for Elastic Polyurethanes) and in particular on page 321 ff. (Chapter 13: Polyether Polyols for Rigid Polyurethane Foams) and page 419 ff. (Chapter 16: Polyester Polyols for Rigid Polyurethane Foams). It is also possible to obtain polyester and polyether polyols from suitable polymer recyclates via glycolysis. Suitable polyether-polycarbonate polyols and their production are described, for example, in EP 2 910 585 A1, [0024] - [0041]. Examples of polycarbonate polyols and their production can be found, inter alia, in EP 1 359 177 A1. The The preparation of suitable polyetherester polyols is described in WO 2010/043624 A and in EP 1 923 417 A, among others.

In addition, the isocyanate-reactive component Al can contain low molecular weight isocyanate-reactive compounds, preferably di- or trifunctional amines and alcohols, preferably diols and / or triols with molar masses M _n less than 400 g / mol, in particular from 60 to 300 g / mol, for example triethanolamine, diethylene glycol, ethylene glycol and glycerine are used. If low molecular weight isocyanate-reactive compounds are used to produce the rigid polyurethane foams, for example in the function of chain extenders and / or crosslinking agents, these are expediently used in an amount of up to 5% by weight, based on the total weight of component Al Commitment.

In addition to the polyols and isocyanate-reactive compounds described above, component Al can contain further isocyanate-reactive compounds, for example graft polyols, polyamines, polyamino alcohols and polythiols. Of course, the isocyanate-reactive components described also include compounds with mixed functionalities.

The component Al can consist of one or more of the above-mentioned isocyanate-reactive components.

Physical blowing agents such as low-boiling organic compounds such as e.g. Hydrocarbons, halogenated hydrocarbons, ethers, ketones, carboxylic acid esters or carbonic acid esters. Organic compounds which are inert to isocyanate component B and have boiling points below 100 ° C., preferably below 50 ° C. at atmospheric pressure are particularly suitable. These boiling points have the advantage that the organic compounds evaporate under the influence of the exothermic polyaddition reaction. Examples of such, preferably used organic compounds are alkanes, such as heptane, hexane, n- and iso-pentane, preferably technical mixtures of n- and iso-pentanes, n- and iso-butane and propane, cycloalkanes, such as. B. cyclopentane and / or cyclohexane, ethers, such as. B. furan, dimethyl ether and diethyl ether, ketones, such as. B. acetone and methyl ethyl ketone, carboxylic acid alkyl esters, such as. B. methyl formate, dimethyl oxalate and ethyl acetate and halogenated hydrocarbons, such as. B. methylene chloride, dichloromonofluoromethane, difluoromethane, trifluoromethane, difluoroethane, tetrafluoroethane, chlorodifluoroethane, l, l-dichloro-2,2,2-trifluoroethane, 2,2-dichloro-2-fluoroethane and heptafluoropropane. The use of (hydro) fluorinated olefins, such as. B. HFO 1233zd (E) (Trans-l-chloro-3,3,3-trifluoro-l-propene) or HFO 1336mzz (Z) (cis-1, 1,1, 4,4,4-

Hexafluoro-2-butene) or additives such as FA 188 from 3M (l, l, l, 2,3,4,5,5,5-nonafluoro-4- (trifluoromethyl) pent-2-en). Also mixtures of two or more of the organic mentioned Connections can be used. The organic compounds can also be used in the form of an emulsion composed of small droplets.

Chemical blowing agents such as water, carboxylic acid and mixtures thereof can also be used as blowing agent A2. These react with isocyanate groups to form the propellant gas, as in the case of water, for example, carbon dioxide is formed and in the case of z. B. formic acid produces carbon dioxide and carbon monoxide. At least one compound selected from the group consisting of formic acid, acetic acid, oxalic acid and ricinoleic acid is preferably used as the carboxylic acid. Water is particularly preferably used as the chemical blowing agent.

Preferably, no halogenated hydrocarbons are used as blowing agents.

At least one compound selected from the group consisting of physical and chemical blowing agents is used as blowing agent A2. Only physical blowing agent is preferably used. In a preferred embodiment, the blowing agents A2 used have an average global warming potential (GWP) of <120, preferably a GWP of <20.

As catalyst A3 for the production of the PUR / PIR foams, compounds are used which accelerate the reaction of the reactive hydrogen atoms, in particular compounds containing hydroxyl groups, with the isocyanate component B, e.g. B. tertiary amines or metal salts. The catalyst components can be metered into the reaction mixture or completely or partially in the isocyanate-reactive component A1.

For example, tertiary amines such as triethylamine, tributylamine, dimethylbenzylamine, dicyclohexylmethylamine, dimethylcyclohexylamine, N, N, N ', N'-

Tetramethyldiaminodiethylether, bis (dimethylaminopropyl) urea, N-methyl- or N-ethylmorpholine, N-cyclohexylmorpholine, N, N, N ', N'-tetramethylethylenediamine, N, N, N, N-tetramethylbutanediamine, N, N, N, N-Tetramethylhexanediamine-1,6, pentamethyldiethylenetriamine, bis [2- (dimethylamino) ethyl] ether, dimethylpiperazine, N-dimethylaminoethylpiperidine, 1,2-dimethylimidazole, 1-azabicyclo- (3,3,0) -octane , 1,4-Diaza-bi-cyclo- (2,2,2) -octane (Dabco) and alkanolamine compounds such as triethanolamine, triisopropanolamine, N-methyl- and N-ethyldiethanolamine, dimethylaminoethanol, 2- (N, N-dimethylaminoethoxy ) ethanol, N, N ', N "-Tris- (dialkylaminoalkyl) hexahydrotriazine, for example N, N', N" -Tris- (dimethylaminopropyl) hexahydrotriazine and triethylenediamine.

It can also be metal salts such. B. alkali or transition metal salts can be used. The transition metal salts used are, for example, zinc, bismuth, iron, lead or, preferably, tin salts. Examples of transition metal salts used are iron (II) chloride, zinc chloride, lead octoate, tin dioctoate, tin diethylhexoate and dibutyltin dilaurate. Especially The transition metal salt is preferably selected from at least one compound from the group consisting of tin dioctoate, tin diethylhexoate and dibutyltin dilaurate. Examples of alkali metal salts are alkali alcoholates, such as. B. sodium methylate and potassium isopropylate, alkali metal carboxylates, such as. B. potassium acetate, and alkali metal salts of long-chain fatty acids with 10 to 20 carbon atoms and optionally pendant OH groups. One or more alkali metal carboxylates are preferably used as the alkali metal salt.

Also suitable as catalyst A3 are: amidines, such as. B. 2,3-dimethyl-3,4,5,6-tetrahydropyrimidine, tetraalkylammonium hydroxides, such as. B. tetramethylammonium hydroxide, alkali hydroxides, such as. B. sodium hydroxide, and tetraalkylammonium or phosphonium carboxylates. Mannich bases and salts of phenols are also suitable catalysts. It is also possible to run the reactions without catalysis. In this case, the catalytic activity of polyols started with amines is used.

If a larger excess of polyisocyanate is used during foaming, the following are also possible catalysts for the trimerization reaction of the excess NCO groups with one another: Catalysts forming isocyanurate groups, for example ammonium ions or alkali metal salts, especially ammonium or alkali metal carboxylates, alone or in combination with tertiary amines. The isocyanurate formation leads to particularly flame-retardant PIR foams.

The above-mentioned catalysts can be used alone or in combination with one another.

If necessary, one or more additives can be used as component A4. Examples of component A4 are surface-active substances, foam stabilizers, cell regulators, fillers, dyes, pigments, anti-hydrolysis agents, fungistatic and bacteriostatic substances.

Suitable surface-active substances are, for example, compounds which serve to support the homogenization of the starting materials and are optionally also suitable for regulating the cell structure of the plastics. Examples include emulsifiers, such as the sodium salts of castor oil sulfates or of fatty acids, and salts of fatty acids with amines, for example oleic diethylamine, stearic diethanolamine, ricinolic acid diethanolamine, salts of sulfonic acids, for example alkali or ammonium salts of dodecylbenzylbenzylbenzate or dinaphthyl sulfonate; Foam stabilizers, such as siloxane oxalkylene copolymers and other organopolysiloxanes, ethoxylated alkylphenols, ethoxylated fatty alcohols, paraffin oils, castor oil or ricinoleic acid esters, Turkish red oil and peanut oil, and cell regulators such as paraffins, fatty alcohols and dimethylpolysiloxanes. To improve the The above-described oligomeric acrylates with polyoxyalkylene and fluoroalkane radicals as side groups are also suitable for emulsifying effect, the cell structure and / or stabilization of the foam.

The usual organic and inorganic fillers, reinforcing agents, weighting agents, agents for improving the abrasion behavior in paints, coating agents, etc., known per se, are to be mentioned as fillers, in particular reinforcing fillers. The following may be mentioned in detail: inorganic fillers such as silicate minerals, for example sheet silicates such as. B. antigorite, serpentine, sepiolite, hornblende, amphibole, chrismotile, montmorillonite and talc, metal oxides such as kaolin, aluminum oxides, titanium oxides and iron oxides, metal salts such as chalk, huntite, barite and inorganic pigments such as magnetite, goethite, cadmium sulfide and zinc sulfide, as well as glass and others as well as natural and synthetic fibrous minerals such as wollastonite, metal and especially glass fibers of various catches, which can optionally be sized. Examples of organic fillers are: carbon, melamine, rosin, cyclopentadienyl resins and graft polymers and cellulose fibers, polyamide, polyacrylonitrile, polyurethane, polyester fibers based on aromatic and / or aliphatic dicarboxylic acid esters and carbon fibers.

A flame retardant A5 is used to produce the PUR / PIR foams, the flame retardant A5 according to the invention containing as component A5.1 dibutylhydroxymethylphosphonate and optionally its dimer. The preparation of the compounds of component A5.1 is known per se and is described, for example, in WO 2010/080425. As a rule, the preparation takes place in the presence of a catalyst and can be carried out without a solvent or in the presence of a solvent.

The compounds of component A5.1 are preferably prepared using a catalyst selected from the group consisting of phosphorus bases, such as phosphazenes or alkali phosphates, alkali carbonates and amines, with the exception of tertiary trialkylamines, particularly preferably selected from the group consisting of phosphorus bases and alkali carbonates .. A phosphorus base is particularly preferably used as a catalyst. Sodium or potassium are preferably used as the alkali metal for the alkali metal phosphates and alkali metal carbonates.

It is also preferred that component A5.1 is prepared without a solvent or in a phosphorus-containing solvent (e.g. hydroxymethylphosphonate).

If the dimer of dibutylhydroxymethylphosphonate is contained in component A5.1, the dimer of dibutylhydroxymethylphosphonate is preferably in a proportion of 0.1 to 30.0 % By weight, particularly preferably 1.0 to 25.0% by weight, very particularly preferably 4.0 to 15.0% by weight, based on the total weight of the dibutylhydroxymethylphosphonate.

In addition to component A5.1, the flame retardant A5 can contain other flame retardants such as phosphates, such as. B. triethyl phosphate (TEP), triphenyl phosphate (TPP), tricresyl phosphate, diphenyl cresyl phosphate (DPK), tert-butylphenyl diphenyl phosphate, resorcinyl diphenyl phosphate (also as oligomer) and bisphenol-A bis (diphenyl phosphate) (also as oligomer). Phosphonates such as diethylethylphosphonate (DEEP), dimethylpropylphosphonate (DMPP), diethanolaminomethylphosphonic acid diethyl ester, Veriquel ^® R100 or “E06-16” from ICL, and also mixed phosphonates such as ethylbutylhydroxymethylphosphonate and phosphinates such as 9,10-oxa-dihydro-10 -phosphorylphenanthrene-10-oxide (DOPO), salts of diphenylphosphinous acid and salts of diethylphosphinous acid Et ₂ P0 ₂ H (Exolit ^® OP 1235, Exolit ^® OP 935, Exolit ^® OP 935, Exolit ^® OP L 1030) can be used. Further suitable flame retardants A5 are, for example, brominated esters, brominated ethers (Ixol) or brominated alcohols such as dibromoneopentyl alcohol, tribromoneopentyl alcohol, tetrabromophthalate diol, and chlorinated phosphates such as tris (2-chloroethyl) phosphate, tris (2-chloropropyl) phosphate (TCPP), tris (1,3-dichloropropyl) phosphate, tris (2,3-dibromopropyl) phosphate, tetrakis (2-chloroethyl) ethylene diphosphate, as well as commercially available halogen-containing flame retardant polyols. Diphenyl cresyl phosphate, triethyl phosphate and bisphenol A bis (diphenyl phosphate) are preferred. It is particularly preferred that no halogen-containing flame retardants are used.

The proportion of component A5.1 in the flame retardant A5 is preferably 30.0% by weight to 100.0% by weight, more preferably 50.0 to 100.0% by weight, in particular 80.0 to 100.0% by weight -%, each based on the total mass of the flame retardant A5.

The proportion of component A5.1 in the reaction mixture is preferably 0.1% by weight to 30.0% by weight, preferably 5.0% by weight to 25.0% by weight, in particular 10.0 to 25% , 0% by weight, based in each case on the total mass of the component Al = 100% by weight.

Suitable isocyanate component B are, for. B. polyisocyanates, d. H. Isocyanates with an NCO functionality of at least 2 are possible. Examples of such suitable polyisocyanates are

1,4-butylene diisocyanate, 1,5-pentane diisocyanate, 1,6-hexamethylene diisocyanate (FIDI), isophorone diisocyanate (IPDI), 2,2,4- and / or 2,4,4-trimethylhexamethylene diisocyanate, the isomeric bis (4,4'- isocyanatocyclohexyl) methanes or mixtures thereof with any isomer content, 1,4-cyclohexylene diisocyanate, 1,4-phenylene diisocyanate, 2,4- and / or 2,6-tolylene diisocyanate (TDI), 1,5-naphthylene diisocyanate, 2,2'- and / or 2,4'- and / or 4,4'-diphenylmethane diisocyanate (MDI) and / or higher homologues (polymeric MDI), 1,3- and / or

1,4-bis- (2-isocyanato-prop-2-yl) -benzene (TMXDI), 1,3-bis- (isocyanatomethyl) benzene (XDI), as well as alkyl-2,6-diisocyanatohexanoate (lysine diisocyanate) with CI- bis C6 alkyl groups. Prefers the isocyanate component B is selected from at least one compound from the group consisting of MDI, polymeric MDI and TDI.

In addition to the above-mentioned polyisocyanates, modified diisocyanates with uretdione, isocyanurate, urethane, carbodiimide, uretonimine, allophanate, biuret, amide, iminooxadiazinedione and / or oxadiazinetrione structure, and unmodified polyisocyanate with more than 2 NCO groups per molecule such as, for example, 4-isocyanatomethyl-1,8-octane diisocyanate (nonane triisocyanate) or triphenylmethane-4,4 ', 4 "-triisocyanate, can also be used.

Instead of or in addition to the abovementioned polyisocyanates, suitable NCO prepolymers can also be used as isocyanate component B. The prepolymers can be prepared by reacting one or more polyisocyanates with one or more polyols, corresponding to the polyols described under the isocyanate-reactive components A1.

The isocyanate index (also called index or isocyanate index) is understood to mean the quotient of the amount of substance [mol] of isocyanate groups actually used and the amount of substance [mol] of isocyanate-reactive groups actually used, multiplied by 100:

Index = (moles of isocyanate groups / moles of isocyanate-reactive groups) * 100

According to the invention, the index in the reaction mixture is 80 to 600, preferably 100 to 500, preferably 200 to 400. This index is particularly preferably in a range from 240 to 400 in which a high proportion of polyisocyanurates (PIR) is present (the foam becomes referred to as PIR foam or PUR / PIR foam) and leads to a higher flame retardancy of the PUR / PIR foam itself. Another particularly preferred range for the isocyanate index is the value range from 90 to 150, in particular from 110 to 150 (the foam is referred to as polyurethane foam (PUR foam)) in which the PUR / PIR foam, for example, is less brittle tends.

The NCO value (also: NCO content, isocyanate content) is determined using EN ISO 11909 (May 2007). Unless otherwise stated, the values are at 25 ° C.

The invention also relates to a PUR / PIR foam which is produced by the method according to the invention.

The PUR / PIR foams according to the invention are produced by one-step processes known to the person skilled in the art, in which the reaction components are reacted continuously or discontinuously with one another and then either manually or with the aid of mechanical devices in the high-pressure or low-pressure process after discharge onto a conveyor belt or in suitable forms for Curing are brought. Examples are in US-A 2,764,565, in G. Oertel (ed.) "Kunststoff-Handbuch", Volume VII, Carl Hanser Verlag, 3rd Edition, Munich 1993, p. 267 ff., And in K. Uhlig ( Ed.) "Polyurethan Taschenbuch", Carl Hanser Verlag, 2nd edition, Vienna 2001, pp. 83-102.

The PUR / PIR foams according to the invention are preferably used for the production of composite elements. The foaming usually takes place here in a continuous or discontinuous manner against at least one cover layer.

The invention therefore also relates to the use of a PUR / PIR foam according to the invention as insulation foam and / or as an adhesion promoter in composite elements, the composite elements comprising a layer comprising a PUR / PIR foam according to the invention and at least one cover layer. The cover layer is at least partially contacted by a layer comprising the PUR / PIR foam according to the invention. Composite elements of the type of interest here are also known as sandwich elements or insulation panels and are generally used as components for soundproofing, insulation, hall construction or facade construction. The cover layers can e.g. Metal sheets, plastic sheets or up to 7 mm thick chipboard form, depending on the purpose of the composite elements. The one or two cover layers can each be a flexible cover layer, e.g. around an aluminum foil, paper, multi-layer cover layers made from paper and aluminum or from mineral fleece, and / or around a rigid cover layer, e.g. made of sheet steel or chipboard.

In a first embodiment, the invention relates to a process for producing PUR / PIR foams by converting a reaction mixture containing them

Al is an isocyanate-reactive component

A2 propellant

A3 catalyst

A4 optionally additive

A5 flame retardant with

B an isocyanate component, the production being carried out with an index from 80 to 600, characterized in that the flame retardant A5 contains as component A5.1 dibutylhydroxymethylphosphonate and optionally its dimer.

In a second embodiment, the invention relates to a method according to the first embodiment, characterized in that the isocyanate-reactive component Al contains a polyester polyol.

In a third embodiment, the invention relates to a method according to the second embodiment, characterized in that the polyester polyol has an OH number in the range from 100 to 400 mg KOH / g.

In a fourth embodiment, the invention relates to a method according to one of embodiments 1 to 3, characterized in that the blowing agent A2 is selected from one or more compounds from the group consisting of halogen-free chemical blowing agents, halogen-free physical blowing agents and (hydro) fluorinated olefins.

In a fifth embodiment, the invention relates to a method according to one of the

Embodiments 1 to 4, characterized in that the flame retardant A5 contains 30.0% by weight to 100.0% by weight, based on the total mass of the flame retardant A5, of component A5.1.

In a sixth embodiment, the invention relates to a method according to one of embodiments 1 to 5, characterized in that the proportion of component A5.1 is 0.1% by weight to 30.0% by weight, based on the total mass of the component Al = 100% by weight and preferably 0.04-0.4 mol of phosphonate per kg of foam.

In a seventh embodiment, the invention relates to a method according to one of the

Embodiments 1 to 6, characterized in that the flame retardant A5 does not contain any halogen-containing flame retardants.

In an eighth embodiment, the invention relates to a method according to one of the

Embodiments 1 to 7, characterized in that component A5.1 was prepared by means of a catalyst selected from at least one compound from the group consisting of phosphorus-containing bases, alkali carbonates and amines, with the exception of tertiary trialkylamines.

In a ninth embodiment, the invention relates to a method according to one of embodiments 1 to 7, characterized in that component A5.1 was produced using a phosphorus base as a catalyst. In a tenth embodiment, the invention relates to a method according to one of embodiments 1 to 7, characterized in that component A5.1 was produced in the absence of tertiary amines and without phosphorus-free solvents.

In an eleventh embodiment, the invention relates to a method according to one of embodiments 1 to 10, characterized in that component A5.1 is a mixture of dibutylhydroxymethylphosphonate and 0.1 to 30% by weight, based on the total weight of the dibutylhydroxymethylphosphonate used Dimer of dibutyl hydroxymethyl phosphonate.

In a twelfth embodiment, the invention relates to a method according to the first embodiment, characterized in that containing the reaction mixture

Al 50% by weight to 100% by weight of one or more polyester polyols and 0% by weight to 20% by weight of one or more polyether polyols, each based on the total weight of component Al,

A2 water and physical blowing agents,

A3 catalyst,

A4 if necessary additive,

A5 Flame retardant containing A5.1 Dibutylhydroxymethylphosphonat and optionally its dimer ,, with

B polymeric isocyanate is reacted.

In a thirteenth embodiment, the invention relates to a method according to the first embodiment, characterized in that it contains a reaction mixture

Al is a polyester polyol with a hydroxyl number of 50 mg KOH / g to 400 mg KOH / g,

A2 propellant, containing a compound selected from the group consisting of halogen-free chemical propellants, halogen-free physical propellants and (hydro) fluorinated olefins,

A3 catalyst containing alkali metal carboxylate and / or di- or trialkylaminomethylphenol, A4 additive, containing a foam stabilizer,

A5 flame retardant containing A5.1 dibutylhydroxymethylphosphonate and optionally its dimer, is reacted with B monomeric and polymeric MDI.

In a fourteenth embodiment, the invention relates to a PUR / PIR foam, obtainable by the method according to one of embodiments 1 to 13.

In a fifteenth embodiment, the invention relates to the use of PUR / PIR foams according to the fourteenth embodiment for producing an insulation material.

In a sixteenth embodiment, the invention relates to a method according to one of embodiments 1 to 13, characterized in that the production takes place with an index from 110 to 150.

In a seventeenth embodiment, the invention relates to a method according to one of embodiments 1 to 13, characterized in that production takes place with a code number from 240 to 390.

Examples

The OH number (hydroxyl number) was determined in accordance with DIN 53240-1 (June 2013). The acid number was determined in accordance with DIN EN ISO 2114 (November 2006). The viscosity was determined on a Physica MCR 501 rheometer from Anton Paar. A cone-plate configuration with a distance of 1 mm was selected (DCP25 measuring system). The polyol (0.1 g) was applied to the rheometer plate and subjected to a shear of 0.01 to 1000 1 / s at 25 ° C. and the viscosity was measured every 10 s for 10 minutes. The viscosity given is averaged over all measuring points.

Diethylhydroxymethylphosphonate (DEHMP) and dibutylhydroxymethylphosphonate (DBHMP) are determined by means of proton-decoupled ³¹ P-NMR spectroscopy on the basis of their signals at 23.8 and

23.7 ppm identified (H3PO4 = 0.0 ppm). The dimers are each made up of two doublets (J _PP = 59 Hz)

17.8 and 25.2 ppm for DEHMP and 18.2 and 25.3 ppm for DBHMP. The O-acetylated derivatives can be identified by their ³¹ P signals at 17.85 ppm (acetylated DEHMP) and 18.0 ppm (acetylated DBHMP) and doublets at 16.7 and 19.7 ppm (dimers of the acetylated DEHMP) Identify or doublets at 16.9 or 19.8 ppm (dimers of the acetylated DBHMP). An indicator D / M is given below which gives the ³¹ P-NMR integrals of the doublet associated with the dimer in the range of 16.5-18.5 ppm to the monomer. The conversion of the indicator D / M to a weight ratio of monomer to dimer takes place under the assumption of the same relaxation time of all phosphorus atoms in the ³¹ P-NMR and neglecting possibly superimposed trace impurities

Input materials:

Al-1 86% by weight of an aliphatic polyester polyol with an OH number of 214 mg KOH / g and a viscosity of 2000 mPas at 25 ° C, produced by reacting a mixture of adipic acid, succinic acid and glutaric acid with ethylene glycol,

14% by weight of an aliphatic polyether polyol with an OH number of 28, 90 mol% of primary OH groups and a viscosity of 860 mPas at 25 ° C (Desmophen ^® L 2830, Covestro Deutschland AG)

Al-2 93% by weight of a polyester polyol based on terephthalic acid, adipic acid and

Diethylene glycol with OH number 195 mg KOH / g,

7 wt .-% of a polyether polyol with a central block of propylene oxide and two terminal blocks of ethylene oxide Al-3 wt .-% of an aromatic 100 polyester polyol having an OH number of 240 mg KOH / g (Stepanpol ^® PS-2352, Fa. Stepan Company)

A2-1 n-pentane

A2-2 water A2-3 mixture of cyclo-pentane and iso-pentane in a weight ratio of 30/70

A3-1 dimethylcyclohexylamine

A3-2 25 wt% potassium acetate in diethylene glycol

A4-1 polyether-modified silicone (Tegostab ^® B8421, Evonik)

A5-1 tris (2-chloroisopropyl) phosphate (Levagard ^® PP, Lanxess) A5-2 diphenyl cresyl phosphate (Disflamoll ^® DPK, Lanxess)

A5-3 cyclic phosphonate with a proportion of 19% by weight phosphorus (Aflammit® PLF

710, Thor GmbH)

BI polymeric MDI with a viscosity of 700 mPas at 25 ° C and an NCO content of 31.5% by weight (Desmodur ^® 44V70L, Covestro Deutschland AG)

A5-4: Production of diethylhydroxymethylphosphonate (DEHMP)

138.1 g diethyl phosphite (1 mol), 36.04 g paraformaldehyde (1.2 mol), 0.2 dm ³ isobutanol, 0.15 dm ³ cyclopentane and 6.9 g potassium carbonate (50 mmol, 5 mol%) are mixed at 35 ° C and heated to reflux for one hour while stirring in a 1 dm ³ four-necked flask with reflux condenser, nitrogen blanket and thermometer. After cooling and filtering, the solvents are drawn off from the mixture on a rotary evaporator at 60 ° C. up to a final vacuum of 10 mbar. A yield of 178.25 grams of a clear liquid remains. The OH number is 300 mg KOH / g, the acid number 5.83 mg KOH / g. D / M = 0.011

Calculated weight ratio of monomer to dimer = 98: 2

A5-5: Production of diethylhydroxymethylphosphonate (DEHMP)

138.1 g diethyl phosphite (1 mol), 0.35 dm ³ 1-butanol and 36.04 g paraformaldehyde (1.2 mol) with stirring in a 0.5 dm ³ four-necked flask with reflux condenser, nitrogen blanket and thermometer at 35 ° C heated. 6.9 grams of dry potassium carbonate are added in portions. The temperature is kept at <60 ° C. with the aid of a water bath. After the addition, the reaction mixture is stirred at 60 ° C. for a total of 1 hour. After cooling and filtering, the solution and the mixture are distilled on a rotary evaporator from increasing to 60 ° C. over four hours to a final vacuum of 10 mbar. A yield of 180 grams is obtained. D / M = 0.009

Calculated weight ratio of monomer to dimer = 98: 2

A5.1-1: Production of dibutylhydroxymethylphosphonate (DBHMP) with potassium phosphate as a catalyst

97.4 g of dibutyl phosphite (0.5 mol), 25.03 g of tributyl phosphite (0.1 mol) and 3.4 g of potassium phosphate K3PO4 (16 mmol, 1.6 mol%) are mixed and, with stirring, in a 0, 5 dm ³ four-necked flask with reflux condenser, nitrogen blanket and thermometer heated to 65 ° C. In parallel, 31.5 g of paraformaldehyde (1.05 mol) in 58.2 g of dibutyl phosphite (0.3 mol) are stirred up in a PE squirt bottle with a magnetic stirrer at 20 ° C. The suspension is dosed in six portions into the four-necked flask. The temperature is kept at <75 ° C. with the aid of a water bath. After the sixth portion, 19.4 g of dibutyl phosphite (0.1 mol) are poured into the squirt bottle and the remaining paraformaldehyde adhering to the walls is rinsed into the four-necked flask. After the addition, the reaction mixture is stirred at 75 ° C. for a total of 4 hours. After cooling, the solution and 9.0 grams of distillate are drawn off from the mixture on a rotary evaporator, increasing from 60 ° C. to 75 ° C. over four hours up to a final vacuum of 10 mbar. A yield of 212.9 grams of a clear liquid remains. The OH number is 212 mg KOH / g, the acid number 0.5 mg KOH / g.

D / M = 0.11

Calculated weight ratio of monomer to dimer = 84:16 A5.1-2: Production of butyl ethyl hydroxymethyl phosphonate with potassium phosphate as a catalyst

97.4 g of dibutyl phosphite (0.5 mol), 16.62 g of triethyl phosphite (0.1 mol) and 1.36 g of potassium phosphate K3PO4 (6.4 mmol, 0.64 mol%) are mixed and, with stirring, in a 0.5 dm ³ four-necked flask with reflux condenser, nitrogen blanket and thermometer heated to 70 ° C. In parallel, 31.5 g of paraformaldehyde (1.05 mol) in 58.2 g of dibutyl phosphite (0.3 mol) are stirred up in a PE squirt bottle with a magnetic stirrer at 20 ° C. The suspension is dosed in six portions into the four-necked flask. The temperature is kept at <75 ° C. with the aid of a water bath. After the sixth portion, 19.4 g of dibutyl phosphite (0.1 mol) are poured into the squirt bottle and the remaining paraformaldehyde adhering to the walls is rinsed into the four-necked flask. After the addition, the reaction mixture is stirred at 75 ° C. for a total of 4 hours. After cooling, the solution and the mixture are drawn off on a rotary evaporator, increasing from 60 ° C. to 75 ° C. over four hours to a final vacuum of 10 mbar distillate (0.9 grams). After filtering through a folded paper filter, there remains a filter residue of 7.6 grams and a yield of 204 grams of a clear liquid. The OH number is 210 mg KOH / g, the acid number 1.45 mg KOH / g.

D / M = 0.06

Calculated weight ratio of monomer to dimer = 91: 9

A5.1-3: Production of dibutylhydroxymethylphosphonate (DBHMP) with potassium phosphate as a catalyst

97.4 g of dibutyl phosphite (0.5 mol), 25.03 g of tributyl phosphite (0.1 mol) and 1.36 g of potassium phosphate K3PO4 (6.4 mmol, 0.64 mol%) are mixed and, with stirring, in a 0.5 dm ³ four-necked flask with reflux condenser, nitrogen blanket and thermometer heated to 70 ° C. In parallel, 31.5 g of paraformaldehyde (1.05 mol) in 58.2 g of dibutyl phosphite (0.3 mol) are stirred up in a PE squirt bottle with a magnetic stirrer at 20 ° C. The suspension is dosed in six portions into the four-necked flask. The temperature is kept at <75 ° C. with the aid of a water bath. After the sixth portion, 19.4 g of dibutyl phosphite (0.1 mol) are poured into the squirt bottle and the remaining paraformaldehyde adhering to the walls is rinsed into the four-necked flask. After the addition, the reaction mixture is stirred at 75 ° C. for a total of 4 hours. After cooling, the solution and the mixture are drawn off on a rotary evaporator, increasing from 60 ° C. to 75 ° C. over four hours to a final vacuum of 10 mbar distillate (5.75 grams). It remains after filtering over one Pleated paper filter had a filter residue of 8.4 grams and a yield of 207 grams of a clear liquid. The OH number is 213 mg KOH / g, the acid number 0.48 mg KOH / g.

D / M = 0.07

Calculated weight ratio of monomer to dimer = 90:10

A5.1-4: Production of dibutylhydroxymethylphosphonate with phosphazene as a catalyst

97.4 g of dibutyl phosphite (0.5 mol), 25.03 g of tributyl phosphite (0.1 mol) and 0.1 g of phosphazene base BTPP (0.32 mmol, 0.032 mol%) are mixed and, with stirring, in a 0, 5 dm ³ four-necked flask with reflux condenser, nitrogen blanket and thermometer heated to 70 ° C. In parallel, 31.5 g of paraformaldehyde (1.05 mol) in 58.2 g of dibutyl phosphite (0.3 mol) are stirred up in a PE squirt bottle with a magnetic stirrer at 20 ° C. The suspension is dosed in six portions into the four-necked flask. The temperature is kept at <75 ° C. with the aid of a water bath. After the sixth portion, 19.4 g of dibutyl phosphite (0.1 mol) are poured into the squirt bottle and the remaining paraformaldehyde adhering to the walls is rinsed into the four-necked flask. After the addition, the reaction mixture is stirred at 75 ° C. for a total of 4 hours. Then the reaction mixture is very clear. After cooling, 8.7 grams of distillate are drawn off from the mixture on a rotary evaporator, increasing from 60 ° C. to 90 ° C. over three hours up to a final vacuum of 10 mbar. A yield of 216.2 grams of a clear liquid remains. The OH number is 203 mg KOH / g, the acid number 1.3 mg KOH / g.

D / M = 0.039

Calculated weight ratio of monomer to dimer = 94: 6

A5.1-5: Production of dibutylhydroxymethylphosphonate with diisopropylethylamine as a catalyst

33.33 mL of the batch of A5-4, 31.5 g of paraformaldehyde (1.05 mol) and 3.05 g of diisopropyethylamine (23.6 mmol, 2.36 mol%) are mixed and stirred in a 0, 5 dm ³ four-necked flask with reflux condenser, nitrogen blanket and thermometer heated to 50 ° C. A mixture of 175 g of dibutyl phosphite (0.9 mol) and 25.03 g of tributyl phosphite (0.1 mol) is metered into the four-necked flask in portions. The temperature is kept at <50 ° C. with the aid of a water bath. After the addition, the mixture is kept at 75 ° C. for two hours touched. Then the reaction mixture is very clear. 14.13 grams of distillate are withdrawn from the raw material on a rotary evaporator, increasing from 45 ° C. to 75 ° C. over three hours to an ultimate vacuum of 10 mbar. A yield of 245.87 grams of a clear liquid remains. The OH number is 204 mg KOH / g, the acid number 2.9 mg KOH / g. D / M = 0.054

Calculated weight ratio of monomer to dimer = 92: 8

A5.1-6: Production of acetylated diethylhydroxymethylphosphonate

In a 0.1 dm ³ round bottom flask, 45 g of A5-5 are stirred with 25 g of acetic anhydride. The reaction is initially slightly exothermic. After standing overnight at room temperature, the mixture is distilled on a rotary evaporator from increasing to 100 ° C. over four hours to a final vacuum of 10 mbar. A yield of 57 grams is obtained. D / M = 0.016

Calculated weight ratio of monomer to dimer = 98: 2.

Production and testing of PUR / PIR foams

The flame spread of the PUR / PIR foams was measured by applying flame to the edges with the small burner test according to DIN 4102-1 (May 1998) on a sample measuring 18 cm x 9 cm x 2 cm. The heat release was measured in accordance with ISO 5660-1 (March 2015) with the "cone calorimeter".

The bulk density was measured in accordance with DIN EN ISO 845 (October 2009).

Tensile tests in accordance with DIN 53430 (September 1975) were used to determine tensile strength (ö _Fmax ), elongation at break (s _Bmch ) and a measure of toughness (ö _Fmax * e _Bmch / 2) on tensile rods (milled according to DIN 53430 5.1). The open-cell content of the PUR / PIR foams was measured with an Accupyk 1330 device on test specimens measuring 5 cm x 3 cm x 3 cm in accordance with DIN EN ISO 4590 (August 2003).

On the basis of the polyol components, PUR / PIR foams were produced in the laboratory by mixing 0.3 dm ^{3 of} a reaction mixture in a paper cup. For this purpose, the flame retardant, foam stabilizer, catalysts and water and pentane as blowing agents were added to the respective polyol component and stirred briefly. The mixture obtained was mixed with the isocyanate and the reaction mixture was poured into a paper mold (3 × 3 × 1 dm ³ ) and completely reacted in it. The exact formulations of the individual experiments are given in the tables below, as are the results of the physical measurements on the samples obtained.

Table la shows the use of dibutyl hydroxymethylphosphonate as a flame retardant (Example 3) in comparison with flame retardants which are representative of the prior art. The PUR / PIR foam produced with the flame retardant according to the invention from Example 3 shows a low flame spread and heat release despite a lower content of flame retardant chlorine and phosphorus. In addition, the PUR / PIR foam from Example 3 has improved values in the tensile test according to DIN 53430 (September 1975) and a lower open-cell content compared with Comparative Examples 1 and 2. Table la

* Comparative example

¹ The data% by weight and mol / kg relate to the total mass of components Al to B l = 100% by weight Table lb shows that the flame retardant according to the invention results in a PUR / PIR foam with improved mechanical properties compared to butyl ethyl hydroxymethylphosphonate as a flame retardant.

Table lb

* Comparative example

¹ The data% by weight and mol / kg relate to the total mass of the components Al bis

Bl = 100% by weight Table 2

¹ The data% by weight and mol / kg relate to the total mass of components A1 to B1 = 100% by weight

Table 2 shows the comparison of the PUR / PIR foams from Examples 6 to 8, which according to the invention contain a component A5.1 as a flame retardant. Components A5.1 in Table 2 were prepared using a phosphorus-containing base (Examples 6 and 6) or an amine (Example 8) as a catalyst. The PUR / PIR foams of Examples 6 to 8 have the same vertical flame propagation. The PUR / PIR foams of Examples 6 and 7 produced according to a preferred embodiment, however, show more advantageous kinetics, which is characterized by the higher ratio of start time / rise time. Table 3

* Comparative example

¹ The data% by weight and mol / kg relate to the total mass of components A1 to B1 = 100% by weight

The results of Tables 3 and 4 show that when acetylated diethylhydroxymethylphosphonate is used as component A5 (Examples 10, 12 and 13), good flame retardancy is obtained. Table 4

* Comparative example

¹ The data% by weight and mol / kg relate to the total mass of the components A1 to B1 = 100% by weight ² The adhesion to paper is assessed according to German school grades by a trained employee.

Claims

Claims

1. A process for the production of PUR / PIR foams by reacting a reaction mixture containing them

Al is an isocyanate-reactive component

A2 propellant

A3 catalyst

A4 optionally additive

A5 flame retardant with

B of an isocyanate component, the production being carried out with an index of 80 to 600, characterized in that the flame retardant A5 contains dibutylhydroxymethylphosphonate and optionally its dimer as component A5.1.

2. The method according to claim 1, characterized in that the isocyanate-reactive component Al contains a polyester polyol.

3. The method according to claim 2, characterized in that the polyester polyol has an OH number in the range from 100 to 400 mg KOH / g.

4. The method according to any one of claims 1 to 3, characterized in that the blowing agent A2 is selected from one or more compounds from the group consisting of halogen-free chemical blowing agents, halogen-free physical blowing agents and (hydro) fluorinated olefins.

5. The method according to any one of claims 1 to 4, characterized in that the

Flame retardant A5 30.0% by weight to 100.0% by weight, based on the total mass of the flame retardant A5, which contains component A5.1.

6. The method according to any one of claims 1 to 5, characterized in that the proportion of component A5.1 0.1 wt .-% to 30.0 wt .-%, based on the total mass of component Al = 100 wt. %, and preferably 0.04-0.4 mol of phosphonate per kg of foam.

7. The method according to any one of claims 1 to 6, characterized in that the

Flame retardant A5 does not contain any halogenated flame retardants.

8. The method according to any one of claims 1 to 7, characterized in that component A5.1 was prepared by means of a catalyst selected from at least one compound from the group consisting of phosphorus bases, alkali carbonates and amines, with the exception of tertiary trialkylamines .

9. The method according to any one of claims 1 to 7, characterized in that component A5.1 was produced by means of a phosphorus base as a catalyst.

10. The method according to any one of claims 1 to 7, characterized in that component A5.1 was prepared in the absence of tertiary amines and without phosphorus-free solvents.

11. The method according to any one of claims 1 to 10, characterized in that component A5.1 is a mixture of dibutylhydroxymethylphosphonate and 0.1 to 30% by weight, based on the total weight of the dibutylhydroxymethylphosphonate used.

12. The method according to claim 1, characterized in that containing the reaction mixture

Al 50% by weight to 100% by weight of one or more polyester polyols and 0% by weight to 20% by weight of one or more polyether polyols, each based on the total weight of component Al,

A2 water and physical blowing agents,

A3 catalyst,

A4 if necessary additive,

A5 flame retardant containing A5.1 dibutylhydroxymethylphosphonate and optionally its dimer with

B polymeric isocyanate is reacted.

13. The method according to claim 1, characterized in that containing a reaction mixture

Al is a polyester polyol with a hydroxyl number of 50 mg KOH / g to 400 mg KOH / g,

A2 propellant, containing a compound selected from the group consisting of halogen-free chemical propellants, halogen-free physical propellants and (hydro) fluorinated olefins,

A3 catalyst containing alkali metal carboxylate and / or di- or trialkylaminomethylphenol,

A4 additive, containing a foam stabilizer,

A5 flame retardant containing A5.1 dibutylhydroxymethylphosphonate and optionally its dimer with

B monomeric and polymeric MDI is implemented.

14. PUR / PIR foam, obtainable by the process according to any one of claims 1 to 13.

15. Use of PUR / PIR foams according to claim 14 for producing an insulation material.