MXPA98001852A - Production of rigid foams based on isocyanates, pirorereparent - Google Patents

Abstract

A process for the production of rigid flame retardant foams, based on isocyanates, is presented by the reaction of: a) organic and / or organic polyisocyanates modified with b) at least one higher molecular weight compound having at least two reactive hydrogen atoms and, if desired c) low molecular weight chain extenders and / or crosslinkers in the presence of d) flame retardants, e) water, f) blowing agents and g) other auxiliaries and / or additives, comprising the use, as agents of expansion, of a mixture of at least one hydrocarbon which is in the liquid state at room temperature and which has 5 or more carbon atoms in the molecule with at least one hydrocarbon which is in a gaseous state at room temperature and which has 4 or less carbon atoms in the molecule

Description

PRODUCTION OF RIGID BASED FOAMS AND ISO IANATOS, PIPOPPETAPDANTES The present invention relates to a process for the production of rigid foams based on i-co-os, pyro-retardants that are empanded without the use of luorochlorohydrocarbons (FCHC), to a mixture of agents of e = pan for the production of these rigid foams based on isocyanates, pyretargettes, and their predominant use as an active material in the sector of construction. Rigid puzzles based on J OCJ anatos, particularly polyurethane foams and isocurated foams, have been known for a long time to be used primarily for insulation against heat or against cold, for example, in cooling devices , in the construction sector, in hot water tanks and in long-distance heating pipes. Until recently, the blowing agents used to produce these foams were FCHCs, especially tr-chlorofluoromethane. Due to its destructive effect on the ozone layer of the atmosphere, these materials must be replaced by materials that do not have a potential to destroy: ozone layer (ODP) and a very low global warming potential (GWP) . For these reasons, hydrocarbons have been proposed as agents of the future. Among the hydrocarbons, the isomers of pentane have a-? Its essential function, its relatively low boiling points, makes them very suitable substances for the production of rigid foams based on isocyanates. The use of pentane derivatives has already been mentioned in the third edition of unststoff-Handbuch, ed. G. Bect-er and D. Braun, Vol. 7, ed. G. Oertel, Carl Hanser Verlag, Munich, Vienna, 1993, for example, on page 115 et seq. The exchange of FCHCs by alternative expansion agents, such as HFCHCs, HFHCs, C02 and particularly low-cost hydrocarbons, increases the cost of achieving a uniformly good rate of retardant performance. This is especially apparent in high amounts of retarder agents that must be added to the formulations. Increased amounts of flame retardants create considerable costs and can give foams with inferior properties. The search for expansion agents based on my efficient carbonates that favorably influence the performance of fire protection and therefore require a very small amount of flame retardant to provide adequate fire protection is therefore an important technical search. The use of hydrocarbons as physical blowing agents as an alternative to the halogen-containing blowing agents, and par- ticularly the expansion of rigid paliuretane foams using pentane, are also described in detail in the p > ubl ications of Heilig, G., Kunststoffe 81 < 1991), pgs. 622-625, and Heilig, G. et al., Kunststoffe 81 (1991), p. 790-794, where reference is also made, inter alia, to the required high proportions of pirorretard ntes. EP-A-041269 proposes, inter alia, as a possibility for the production of rigid polyurethane foams having a low thermal conductivity, mixtures of cyclopentane and / or cyclohexane expansion agents with hydrocarbons having 4 or more. fewer carbon atoms. Thus, it is preferred to operate without rhein retardants. An increased protection against flames is not a purpose of the invention described herein. Our own Patent Application No. 19526979.9 describes the use, as blowing agents, of cyclopentane and / or other low-boiling hydrocarbons together with low molecular weight manofluoric alcohols, containing primary or secondary hydroxide, if desired in association with water, to improve the flow behavior in the foam formation reaction mixture. In the case of rigid polyurethane foams that have low densities and an increased thermal insulation capacity, EP-A-0657495 discloses, as mixtures of halogen-free blowing agents, azeotropic mixtures of cycloaliphatic hydrocarbons having from 5 to 7 carbon atoms with carba-1-ions, ketones. or ethers that are in liquid state at room temperature. Due to their high polarity, the oxygen containing constituents employed in the described azeotropic mixtures are dissolved at a significant magnitude in the polyurethane matrix. The resulting asphyxiating effect affects the mechanical properties. Particularly in the case of low density foams, a tendency to shrink is created. It is an object of the present invention to discover expansion agents that do not have the indicated limitations and that beneficially affect the performance of foams in case of fire. We have found that this object is achieved, surprisingly by the use, as extension agents, of a mixture of at least one hydrocarbon which is in the liquid state at room temperature and which has 5 or more carbon atoms in the molecule with at least one gaseous hydrocarbon at room temperature and having 4 or fewer carbon atoms in the molecule. The invention therefore provides a process for the production of rigid foams based on isogranate, flame retardants by the reaction of: a) organic and / or organic polyisocytes modified with b) at least one compound of molecular weight - ^ s high that has to the menu-- »two reactive hydrogen atoms and, if desired c) extenders of ba chains or molecular weight and / or reticlers in the presence of d) pi retardants, e) water, f) expansion agents and g) other auxiliaries and / or additives, comprising the use, as blowing agents, of a mixture of at least one hydrocarbon which is in the liquid state at room temperature and which has 5 or more carbon atoms in the molecule with less a gaseous hydrocarbon at room temperature and having 4 or less carbon atoms in the molecule. The invention also provides a blowing agent mixture for the production of rigid foams based on isocyanate, flame retardants and their use as a material in isolation in the field of construction. A particularly surprising discovery was that the additional use of gaseous, highly flammable hydrocarbons with 4 or less carbon atoms, which also includes high energy b fuels in known as liquefied petroleum gases, reduces the combusibility of the foams. . From the class consisting of hydrocarbons that are in the liquid state at room temperature and having 5 or more carbon atoms in the molecule, cyclic and non-cyclic representatives can be used. The desired effects are achieved with the use of alkanes and alkenes. Preference is given to u >They have 5 or 6 carbon atoms, such as, for example, N-hexane and its isomers, 1-, 2- and 3-hexene and their isomers, c? clohe, anus and me? lohexane. Particularly advantageous and therefore particularly preferred hydrocarbons are N-pentane, isopentane, neopentane and cyclopentane. However, it is also possible to employ other liquid hydrocarbons, particularly alkanes and alkenes and their isomers having from seven to ten atoms of carbon in the molecule, for example n-heptane, n-octane, n-nonane, n-decane and their isomers, I-cyclohexane, the isomers of dime and the cyclohexane and the isomers of heptene, actene, noneno and decene. These liquid hydrocarbons can be used individually or in mixtures between them. Of the lase consisting of hydrocarbons that are in a gaseous state at room temperature, and having four or fewer carbon atoms in the molecule, those with three or four carbon atoms, such as propane, cyclopropane, propene, are preferred. ci lobu ano, 1 -butene, cis- and trans-2-butene, isobutene and met i lcic lopropano. The use of n-butane and isobutane is especially preferred. It is also possible, however, to use methane, ethane and ethene. These gaseous hydrocarbons can be used alone or in mixtures between them. The hydrocarbons which are in the liquid state at room temperature and which have 5 or more carbon atoms in the molecule are preferably used in an amount of 0.1 to 10 * /. in weight, particularly in an amount of 2 to 6? by weight, based on the total amount of the foam. The hydrocarbons which are in the gaseous state at room temperature and which have four or less carbon atoms in the molecule are preferably used in an amount of 0.1 to 10% by weight, particularly in an amount of 2 to 6%. by weight, based on the total amount of the foam. For the production of rigid foams based on isocyanates, flame retardants in accordance with the present invention, it is preferred to employ a mixture of blowing agents consisting of a mixture of a number of hydrocarbons which are in the liquid state at room temperature and which have a mixture of hydrocarbons. or more carbon atoms in the molecule with a number of hydrocarbons that are in a gaseous state at room temperature and that have 4 or less carbon atoms in the molecule; This mixture of expansion agents develops its expansion effect together with the carbon dioxide produced from water and isociety. the mixture of hydrocarbons found in this liquid at room temperature and have 5 or more carbon atoms in the molecule with hydrocarbons that are in a gaseous state at room temperature and that have 4 or less carbon atoms in the molecule can be prepared separately by pre-mixing these components, for example in a ba or pressure autoclave. This mixture is added after preference to the polio component! in a conventional way. It is also possible to add the hydrocarbon components individually in the material flow, preferably in the polyol component, immediately before it passes through the mixed head to mix the polyol component and the iso-linate component. The addition in the mixing head of specific multiple components is also possible. The handling of hydrocarbons with pumps, measuring devices and storage vessels is carried out in a known manner. The rigid isocyanate-based, pyretardant based foams according to the present invention are produced by the reaction, in a manner known per se, of a) organic polyisocyanates and? organic modified with b > at least one compound of higher molecular weight having at least two reactive hydrogen atoms and, if desired, c > chain extenders of ba or molecular weight and / or crosslinkers in the presence of d) py retardants, e) water, f) the mixture of novel expansion agents and g) other auxiliaries and / or additives. These rigid foams based on isocyanate are especially foams containing urethane groups and / or isocyanurate groups and / or biuret groups and / or allophanate groups and / or uretdione groups and / or urea groups and / or arbodiimide groups as characteristic structural chemical elements. With the exception of expansion agents (d), the constituents used for the production of the rigid foams based on isocyanate in the novel process are known per se, and are individually described with inuación. a) Suitable organic isolates are the aliphatic, cycloal ifatic, aphatic and preferably aramidic isocyanates and the aramics known per se. Specific examples are: alkylene diisocyanates having from 4 to 12 carbon atoms in the alkylene radical, as well as 1, 12-d 11 dodecane sortarate, 1,4-diisocyanate of 2-e 11 amet i 1 no, 1, 5- ii so wool to 2- eti Ipenta ei lena, 1, -d? iso ianato de tet ramet i leño and preferably 1, 6-d? hexamet isocyanate and wood; di-cycloal isocyanates, for example 1,3- and 1,4-d? cyclohexy aniscianate and any desired mixture of these isomers, 1-? or? a to-3,3,5-tmett 11-5- isocinatom ti lci lohexane (diisocyanate of isophorone), 2,4- and 2,6-hexahydrothol diisocyanate and mixtures of corresponding isomers, 4,4'-, 2,2'- / 2,4'-diisocyanates of dicyclohexylmethane and mixtures of corresponding isomers, and preferably aromatic isocyanates and polyisocyanates such as 2,4- and 2-diisocyanates. , Tol-6-diisocyanate full and the corresponding isomer mixtures, 4,4'-, 2,4'- and 2,2'-d? Isocyanate of diphenylmethane and mixtures of corresponding isomers, mixtures of diphenylmethane 4,4'- and 2,4'-diisolates, polyisocyanates of polyphenol and polypropylene, mixtures of 4,4'-, 2,4'- and 2,2'-diisolanes of di-phenemethane and polyisocyanates of polynuclear poly (pure MDI) and those of crude MDI and di-isocyanates of full tol. The organic di- and polyisocyanates can be used individually or in the form of their mixtures. It is frequently used modified iso-janatos pol i fune i ona ie products obtained by chemical reaction of organic di- and / or polyisocyanates. Examples are di- and / or polyisocyanates containing ester groups, ureas, biuret groups, aliphatic groups, carbohydrate groups, iso-nur-to groups, uretdione groups and / or urethane groups. Specific examples are: pal isocyanates, preferably aromatic, containing urethane groups and having NCO contents of 33.6 to 15 * /. by weight, preferably from 31 to 21! > . by weight, based on the total weight, for example, with diol s, triols, dical diaceters, low molecular weight or low molecular weight polymers having molecular weights of up to 6000, particularly having weight Molecules of up to 1500, 4, 4 '-di-di-methane diisocyanate, mixtures of modified 4,4'- and 2,4'-di-phenylmethane diisocyanate, modified raw MDI or 2,4- and / or 2.6 ~ d? tolylene isocyanate, examples of dialkylene glycols or polyalkylene glycans, which may be used indi idually or as mixtures, are: full diet, dipropylene, polyoxyethylene, polypropylene and polyoxypropyl-polyole ioxieti lengl icoles, and the corresponding trioles and / or tetroles. Other suitable compounds are prepolies containing NCO groups and having NCO contents of 25 to 3.5. by weight, preferably from 21 to 1% by weight, based on the total weight, and prepared from polyester polyols and / or preferably polyether polyols described in conjunction with and 4,4 '-di iso vana of di-phenol-1-methane, mixtures of 2,4'- and 4'-di-di-a-di-phenylenediane, 2,4'- and / or 2,6-diisocyanate of tolylene or crude MDI . Polyisocyanates containing liquid carbodiimide groups and / or isocyanurate rings and having an NCO content of 33.6 to 1% by weight, preferably 31 to 2% * /% by weight, based on total weight, for example those based on in 4,4'-, 2,4'- and / or 2,2'-di-di-ferul ethane and / or 2,4- and / or 2,6-di-tolylene isocyanate also proved to be tools. The modified polyisoathates can, if desired, be mixed with each other or with unmodified organic polyisocyanates, such as 2,4'- or 4,4'-diphenylmethane diisocyanate, crude MDI, 2,4- and / or tolylene 2,6-diisocyanate. Organic polymers which have proven to be especially useful are mixtures of isomers of diphenylmethane diisocyanate or crude MDI having an isomer content of diphenylmethane diisocyanate of 33 to 55% by weight, and polyisocyanate mixtures which contain urethane groups and based on diphenylmethane diisocyanate having an NCO content of 15 to 33% by weight, b) Compounds (b) of molecular weight more than or having at least two reactive hydrogen atoms are those which have a function from 2 to 8, preferably from 2 to 6, and a molecular weight of 300 to 8000, preferably 300 to 300O. Examples of compounds having proven utility are polyether polyols and / or preferably polyols selected from the class consisting of polyether polyols, polyester palols, polythioether polyols, polyether polyols, hydroxyl containing polysaccharides, polycarbonate aliphatics containing hydroxyl and mixtures of at least two of the mentioned polyols. Preference is given to the use of polyester polyols and / or polyether polyols. The hydration number of the polyhydroxy compounds herein is generally 150 to 850 mg K0H / g and preferably 200 to 600 mg KOH / g. Suitable polyesters of polyesters can be prepared, for example, from organic dicarboxylic acids having from 2 to 12 carbon atoms, preferably dicarboxylic acids at ions having 4 to 6 carbon atoms, and alcohols i-hydroxides, preferably diols, having from 2 to 12 carbon atoms, preferably from 2 to 6 carbon atoms. Examples of organic acids are: succimeric acid, gluthac acid, adipic acid, s? Bepic acid, azelaic acid, sebacic acid, decandicarboxylic acid, aleic acid, fumaric acid, phthalic acid, isophthalic acid and Acid teref ico. The dicarboxylic acids here can also be used either in mixtures between them or individually. The corresponding derivatives of dicarboxylic acids, such as steres d? Carbo. <; Alcohols having 1 to 4 carbon atoms or dicarboxylic anhydrides can also be used in place of the free dicarboxylic acids. Preference is given to the use of mixtures of dicarboxylic acids of succinic acid, glutApco and adipic in a proportion of mixtures of, for example, 20 to 35: from 35 to 50: from 20 to 32 part by weight, and in particular Acid adípieo. Examples of dihydric and polyhydric alcohols, particularly diols, are: ethanediol, diethyl glycol, 1,2- and 1,3-propandol, dipropyl glycol, 1,4-butanediol, 1,5-pentanediol, 1 , 6-hexand? Ol, 1, 10-decand? Ol, glycerol and tr i et i lolpropane. Preference is given to the use of etandial, di etiolglycol, 1,4-butanediol, 1,5-pentandol, 1,6-hexanediol, or mixtures of at least two of the said diols, particularly mixtures of 1 , 4-butandol, 1,5-pentanediol, and 1,6-hexandol. Lactone-derived polyester polyols, such as, for example, epsi-caprolactone, or hydroxycarboxylic acids, such as, for example, ega-hydroxycaproic, may also be used. To prepare the polyester polyols, the organic polycarboxylic acids, for example aramics and preferably aliphatics and / or their derivatives and polyhydric alcohols can be polymerized without catalysts or preferably in the presence of esterification catalysts conveniently in an atmosphere of inert gas, such as nitrogen, carbon monoxide, helium, argon, etc., in the form of a melt at a temperature between 150 and 250 ° C, preferably between 180 and 220 ° C, under reduced pressure if desired, up to the index of desired acidity, preferably less than 10, more preferably less than 2. In a preferred embodiment, the esterification mixture is polycondensed at the temperatures mentioned above until an acid number of 80 to 30 is obtained, preferably from 40 to 30, under atmospheric pressure, and then under a pressure of less than 500 mbar, preferably from 50 to 150 mbar. Examples of suitable esterification catalysts are iron, cadmium, cobalt, chromium, zinc, antimony, magnesium, titanium and tin, in the form of metals, metal oxides or metal salts. The polycondensation can, however, also be carried out in the liquid phase in the presence of diluents and / or entrainers, such as, for example, benzene, toluene, xylene or chlorobenzene, for the removal of the condensation water with azeotropic distillation. To prepare the polyester polyols, the organic polycarboxylic acids and / or their derivatives and polyhydric alcohols are advantageously polyconcentrated in a malar proportion of 1: from 1 to 1.8, preferably 1: from 1.0 to 1.2. The resulting polyester polyols preferably have a functionality of 2 to 4, particularly 2 to 3, and a molecular weight of 480 to 3000, preferably 600 to 2000, and particularly 600 to 1500. However, polyols which They are used in particular polyester polyols in particular, they are polyester pallets prepared by known processes from one or more full-oxide oxides having from 2 to 4 carbon atoms in the alkylene radical, for example by ammonium polymerization using alkali metal hydroxides, such as for example sodium hydroxide or potassium hydroxide, or alkali metal alkoxides with, for example, sodium, sodium, potassium heptoxide or potassium isopropoxide as catalysts and with addition of at least one initiator molecule having from 2 to 8, preferably from 2 to 6 reactive hydrogen atoms in its structure, or by cationic polymerisation empl with Lewis acid, such as, for example, antimony pentachloride, boron fluoride etherate, etc., or bleaching earths or catalysts. Examples of oxides of suitable full strength are tetrahydrofurans, 1,3-propylene oxide, 1,2- and 2,3-buylene oxide, styrene oxide and preferably ethylene oxide and sodium oxide., 2-prop? him or The alkylene oxides can be used individually, alternately in sequence or as mixtures. Examples of initiator molecules are: water, organic di-carboxylic acids, such as, for example, succinic acid, adipic acid, ophthalmic acid and terephthalic acid, ifrathic and aromatic diamines which may be unsubstituted or may have an substitution N-mono-, N, N- or N, NO-d? alqu? 1, which have from 1 to 4 carbon atoms in an alkyl radical, such as, for example, ethylene diamine, dietary supplement, intravenous agent, 1,3-propyl, lendiami n, 1,3- or 1, 4-but i lendi mi n, 1,2-, 1,3-, 1,4-, 1.5- or 1, 6-hexameth and lend lamina, feni lendla ina, 2 , 3-, 2,4-, or 2, - ol i lendiamine, 4,4'-, 2,4'- or 2, -dia substituted or unsubstituted mono- or dialkyl dialdehyde. Other initiator molecules which are suitable are: alkanolamines, for example ethanolane and N-methyl- and N-et-i-ethanolamine, dialkanolamines, such as, for example, diethanolamine and N-methyl and N-et i-lietethanol, and t-alkanolamines, as for example tpetanola ina, and ammonia. Preference is given to the use of polyhydric alcohols, particularly dihydroxyl and / or trihydric alcohols, such as, for example, ethanediol, 1,2-propandol, 1,3-propandol, diethylglycole, dipropyl, 1, 4-butand. ol, 1,6-hexanediol, glycerol, tri et iolpropane, pentaep tri tol, sorbitan and sucrose.

The preferred polyols, of reference palióles de pol ioxo op i leño and polio! they have a polyoxynole-polyolethylene structure, have a functionality preferably of 2 to 6 and particularly of 2 to 4, and molecular weights of 300 to 3000 preferably 300 to 2000, and particularly of 400 to 2000, and suitable polymethyl tetramethyl glycols have a molecular weight of up to approximately 3,500. Other suitable polyol polyols are polyether polyols modified with polymers, preferably polyether graft polyols, particularly those based on styrene and / or Acrylated and prepared by the in situ polymerization of acrylonitrile, styrene or preferably mixtures of styrene and acrylonitrile, for example in a weight ratio of 90:10 to 10:90, preferably from 70:30 to 30:70, conveniently in the aforementioned polyester polyols, based on the information provided in the German patents nos. 11 ti 394, 12 22 669 (US 3 304 273, 3 383 351, 3 523 093), 11 52 536 (GB 10 40 452) and 11 52 537 (GB 987 618), and dispersions of polyester polyol that they contain, for example, as a dispersed phase, usually an amount of 1 to 50% by weight, preferably 2 to 25% by weight, examples being polyureas, polyhydrates, melamine and / or polyurethanes containing linked tertiary amino groups, and which are described, for example, in EP-B-011 752 (US 4 304 708), US-A-4 374 209 and DE-A-2 1 4 ^. The pali ether polyols can, like the polyester pallets, in the individual or in the form of mixtures. They can also be mixed with the graft polyester polyols or the polyester polyols and with the polyester amides containing hydroxide, polyketals, polycarbonates, and / or polyether polyamines. Examples of hydroxyl-containing polyacetals are those compounds which are usually prepared from glycols, for example dietary glycol, toluene, 4,4'-dihydroxyethoxydi-phenyldimethenemethane or hexandiol and formaldehyde. Suitable polyacetals can also be prepared by polymerization of cyclic acetals. Suitable hydroxyl-containing carbonates are those of the type known per se, which can be prepared, for example, by the reaction of diols, for example 1,3-propanedione, 1,4-butane, and / or 1, 6. -hexand? ol, die i lengl icol, trieti lengl icol or tetrae i lengl icol with diaplated carbonates, such as for example carbonate of differen or phosgene. Examples of polyester amides are the predominantly linear compounds obtained from saturated or polybasic unsaturated carboxylic acids and / or their anhydrides and / or saturated polyol and / or unsaturated alcohols or mixtures of polyhydric alcohols and ammoalcohols and / or pol laminates.

Suitable polyether polyols can be prepared from the polyether polyesters mentioned above - by known processes, for example, the polyalcoalkylene ionization of polyoxyalkylene polyols followed by the hydrogenation of the resultant nickel < US 3 267 050) or the partial or complete addition of polyol IO polyols with amines or ammonia in the presence of hydrogen and catalysts (DE 12 15 373). c) Rigid foams based on isocyanate can be produced with or without the additional use of chain extenders and / or reticulate. The addition of chain extenders, crosslinkers or other, if desired, mixtures of these can prove to be useful, however, to modify the mechanical properties, for example rigidity. The former chain-linkers and / or the crosslinkers used are diols and / or triols having molecular weights of less than 400, preferably from 60 to 300. Examples of these are aliphatic diols, ie,! i phthalates and / or araliphatics having 2 to 14, preferably 4 to 10 carbon atoms, such as, for example, polyglotol, 1, 3-propandol, 1, 10-decane, or-, m- and p-dihydroxycyclohexane, di et i lengl icol, dipropyl glycol and, preferably, 1,4-butanediol, 1,6-hexanediol and bis (2-hydroxyl et? 1) -hydroquinone, triols, for example 1,2 , 4- and 1,3,5-tr ihi rox iciclohexano, glycerol yti me i lolpropano, and polyalkylene oxides containing low molecular weight hydrophilic based on ethylene oxide and / or 1,2-pro full oxide and the aforementioned diols and / or triols as initiator molecules. If chain extenders, refiners or mixtures of these are used for the production of rigid foams based on isocyanates, these are conveniently used in an amount of about 2 to 2014 by weight, preferably 2 to 81. by weight , based on the weight of component (b). d) The rigid isocyanate-based foams according to the present invention are flame retardant. The flame retardants used can be any of the usual materials used for this purpose in the chemistry of polyurethanes. Halogen compounds and phosphorus compounds are used predatantly. Examples of suitable ferrous irritants are tricresila phosphate, tris (2-chloroet i) phosphate phosphate, tris (2-chloropropyl) phosphate, tris (1,3-chloropropyl) phosphate, tris phosphate. (2, -di-bromopro), and tetrakis phosphate (2-chloroethexethane-ethylphosphonate, diethyllaminomethyl-1-phosphonate, and commercially available halogen-containing polyols that are commercially available. Isocyanate-based rigid foam of the future should only be produced using halogen-free additives, the pipellants should also be free of halogen, examples of which are phosphoric acid, phosphorous acid or phosphonic acid derivatives, which react with the natural gas; these may, if desired, be combined with liquid and / or non-reactive halogen-free solids, for example those made from organic phosphoric acid derivatives, phosphonic acid or phosphorous acid and / or phosphoric acid salts . Apart from the aforementioned materials, it is also possible to use organic or inorganic flame retardants, for example phosphorus or alumina hydrate, antimony trioxide, arsenic oxide, ammonium polyphosphate and calcium sulfate, expandable graphite or cyanuric acid derivatives. , for example elamina, or mixtures of at least two flame retardants, such as, for example, ammonium polyphosphate and melamine and, if desired, corn starch or ammonium polyphosphate, melamine and graphite e, < pand? t) him Particular reference is made to tris phosphate. -clorapropí lo), derivatives of phosphonic acid, ammonium poly folate and graphite expand ib le. The use of the novel mixture (f) of halogen-free blowing agents of liquid and gaseous hydrocarbons avoids the use of large quantities of unnecessary hydrocarbons. " therefore makes an indirect contribution to 1 - protection against flames. It has generally been found convenient to use from 5 to 50 parts by weight, preferably from 5 to 25 parts by weight, of the aforementioned polypropylene per 100 parts by weight of component fb). e) Water is used as a chemical expansion agent and reacts with isocose component (a) bleach groups with carbon dioxide formation. The water is preferably added to component (b) in an amount of 0.5 to 51. by weight, based on the weight of component (b). The addition of water can be combined with the use of the blowing agents to be used in accordance with the present invention. f) For the production of rigid pyretardant foams, based on isocyanate, according to the present invention, as described above, a mixture of blowing agents consisting of a mixture of at least one hydrocarbon is prepared. non-cyclic that is in liquid state at ambient temperature and that has 5 or more carbon atoms in the molecule and at least one hydrocarbon that is in a gaseous state at room temperature and that have 4 or less carbon atoms in the molecule. As described above, the novel mixture of blowing agents is advantageously introduced into the polyol component consisting of the formative components (b), (d), (e), the catalysts (g) and, if -i, (c) and other auxiliaries and O aditi or * - (g), or the hydrocarbons are added in a manner i div í ul. g) For the production of rigid foams or flame retardants, catalysts are usually used and, if desired, other auxiliaries and / or additives. The compounds used as catalysts (g) are particularly those which cause a marked acceleration of the reaction of the compounds of component (b) containing reactive hydrogen atoms, particularly hydroxyl groups and (c) if used, with the polymers. organic isocyanates, modified or unmodified (a).

As suitable catalysts (g), the isocyanate groups can, however, also be introduced to react with each other, preferably providing isocyanurate structures, in addition to the adducts between the isocyanates a) and the compounds < b) that have groups with active hydrogen. The catalysts used are therefore particularly those which accelerate the reactions of the isacyanates, specifically urethane, urea and isocyanurate formation. Preferred compounds for this purpose are tertiary amines, tin compounds, bismuth compounds, alkali metal carboisylates, metal earbaxylates -3 of alkaline earths, quaternary ammonium salts, s- he: hydratriac inas and trt s (dí I u i l nomet 11) phenol es. Examples of suitable catalysts are organometallic compounds, preferably organotin compounds, such as, for example, tin salts (11) of organic carboxylic acids, for example tin (II) acetate, tin (II) octoate, tin ethylhexoate ( II) and laura or tin (II), and dialkyl salts year (IV) of organic carboxylic acids, such as dibutyltin diacetate, dibutyltin dilaurate, dibutyltin maleate, and dioctyltin diacetate. The organometallic compounds are used alone or, preferably, in combination with highly basic amines, for example, for such as 2,3-dimeti 1-3, 4,5,6-tetrahydrapyrimidine, tertiary amines, for example triethyl amines. Laminate, tributylamine, dimethybenzyl, N-methyl-, IM-ethyl- and N -hexahexylmorphine, N, N, N ', N'- tetrame i let i lend amine, N, N,', -te ramet i lbutandi mine, N, N, ', N' -tetramet i 1 - 1, 6-hex and iami na, pentamet Idiet ilentriamin, tetramet i 1 diaminoetyl ether, bis (di et i laminopropi 1) ure, dimet i lp ipera ina, 3j2-dimet i 1 imidazo], 1-azab? c ic lo (3.3.0) octane and 1,4-d? azabicyclo (2.2.2) octane, and alkanolamine compounds, such as, for example, rietanolamine, isopropanolamine, N-methyl- and N-ethyldiethanolamine and dimethylatanolamine.

Other suitable factors are: tri (di l qui la non lqui 1) -s-he, .ah ídrotna i ñas, parti.culmente tris < N, N ~ d? et il mero op.11) -s- hexahydrotpazin, hydroxides of tetraa lichi lamomos, such as for example tetramethyl ammonium hydroxide, alkali metal hydroxides, such as for example sodium hydroxide and oxalic alkali metal alkoxides eg sodium methoxide e potassium isopropoxide, and alkali metal salts of long chain fatty acids having from 10 to 20 carbon atoms and with or without OH side groups. It is preferable to employ from 0.001 to 514 by weight, particularly from 0.05 to 2% by weight, of catalyst or combination of catalysts, based on the weight of component (b). Additional auxiliaries or additives (g) can, if desired, also be incorporated into the reaction mixture for the production of the rigid isocyanate-based foams according to the invention in addition to the catchers. Examples of these are surfers, foam stabilizers, cell regulators, fillers, dyes, pigments, agents for protection against hydrolysis and substances with a fungistatic and bactericidal action. Examples of suitable surfactants are compounds which serve to promote the generation of the initial materials and, if desired, are also suitable for regulating the cellular structure of the p3Ast? Cos. Examples of these are e ulsif icants, such as, for example, the sodium salts of castor oil, or of fatty acids, and salts of:? > Fatty acids with amines, such as, for example, diethylamine oleate, diethanolamine stearate, diethanolamine ricinoleate, salts of sulphonic acids, such as, for example, ammonium salts or alkaline metals of dodec and lbence acids, or dinf ti lme nd iu 1 phonic and pcinoleic acid; foam stabilizers, for example, copolol, 1-loxano-oxalkyl wood, and other organopolysi loxanesAlkyl 1 phenol is oxetaxides, oxethylated fatty alcohols, paraffin oils, castor oil esters, pcinoleic acid esters, ro or Turkish oil and peanut oil, and cell regulators, such as paraffins, fatty alcohols and dimet i Ipol i si loxane. Suitable compounds for improving the emulsification action, the cell structure and / or the stabilization of the cell are also the aligamépc acrylates having radicals of polyalkyl loxyalkylene and fluoroalkane camo side groups in accordance with the above described . The surfactants are usually used in amounts of 0.01 to 5 parts by weight, based on 100 parts by weight of the compiept (b). The term "rearers", particularly reinforcing fillers, means the usual organic and inorganic reagents, reinforcing agents, weighting agents, agents for improving the abrasion behavior of the coating, coating agents, etc., which are known per se. Specific examples are: inorganic fillers, such as, for example, silicate minerals, for example phyllosilicates, such as, for example, antigapta, serpentine, hornblende, amphiboles, cpsotyl and talc.; metal oxides, such as, for example, kaolin, aluminum oxide, titanium oxides and iron oxides, such as, for example, gis, barite, inorganic pigments, for example cadmium sulfide, zinc sulphide and glass, etc. Preferably use kaolin (Chinese clay), aluminum silicate and coprec? P? of barium sulfate and aluminum silicate, and natural and synthetic fibrous minerals, such as, for example, olastonite, metal fibers and particularly glass fibers of varying lengths which can be provided with a size if desired. Examples of organic reamers are: starch, carbon, melamine, rosin, cyclopentadienyl resins, graft polymers, cellulose fibers, polyamide fibers, polyacrylonitrile fibers, polyurethane fibers, polyester fibers based on esters of organic acids and aromatic and / or aliphatic acids, and particularly carbon fibers. Inorganic and organic fillers can be used individually or as mixtures and are incorporated with * - or advantage in the reaction mixture in amounts of 0.5 to 5014 by weight, preferably 1 to 4014 by weight, in Liase on the weight of the components (a) to ic), where, however, the content of mats, Nonwovens and fabrics made from natural and synthetic fibers can reach values up to 80. Additional details regarding the initial materials mentioned above can be found in the specialized literature, for example in the Monograph by HJ Saunders and 1.C. Frisch, High Polymers, Vol. XVI, Polyurethanes, Parts 1 and 2, Interscience Publishers 1962 and 1964, or the above-mentioned \ unststoffhandbuch, Polyurethane, Vol. VII, Carl Hanser Verlag, Munich, Vienna, Rie., 2d. and 3rd editions, 1966, 1983 and 1993. For the production of rigid isocyanate-based foams, modified organic (a), organic and / or organic polyisocyanates, higher molecular weight compounds having at least two hydrogen atoms reagents (b) and, if desired, chain extenders / or re-catchers (c) react in quantities that give a pri- PurI'- "i" of equivalents between NC0 groups in the polysaccharides (a) and the total of the reactive hydrogen atoms in components (b), and if employed, (c) from 0.85 to 1.75: 3, preferably from 1.0 to 1.3.1, and particularly from 1.1 to 3.2: 1. the rigid foams based on isocyanate contain, 3] less up to a certain point, isocyanurate groups in their structures, the ratio between the NCO groups in the pal 11 soc aanites (a) and the total of the reactive hydrogen atoms in component (b) and, if used, (c) is available from 1.5 to 60: 1, preferably from 3 to 8: 1. 3 rigid foams Isocyanate-based adducts according to the present invention produce d < Preference by means of the molding process or spraying, using particularly block or esp > umas of mold or continuous production in the process of double conveyor belt. It is advantageous to operate with the monostable process, for example, using high-pressure or pressure-fed technology, in open or closed molds. It has proved especially useful to operate the process of the components and combine the components for (b), (d), (e), (f) and catalysts (g) and, if used (c) and other auxiliaries and / or additives (g) in the component (A) and using the organic polyassociates and / or the modified polysiloxanes (a) or mixtures of these piol socianates and, if desired, blowing agent ( f) as the component (B) The initial components are mixed at a temperature comprised between 15 and 90 ° C, preferably 20 to 60 ° C, par- ticularly 20 to 35 ° C, and introduced into the open mold or, if The mixing can be carried out, as already established, mechanically using a spiral mixer or another agitator.The temperature of the mold is conveniently located between 20 and 13 ° C, preferably from 30 to 60 ° C, and in particular from 45 to 50 ° C. In closed molds, it is also possible to use more mixture. of the foam forming reaction that is required to completely fill the mold, thereby providing compressed foams. Rigid polyurethane foams or rigid molded foams produced by the novel process need 0.02 to 0.75 g / cm3, preferably 0.025 to 0.24 g / cm3, and particularly 0.03 to 0.1 g / cm3. The products are preferably used as thermally insulating construction materials. The invention will be described in greater detail using the following working examples: Working example 1-4 and comparative examples 3-2: The following polyol (polyol) mixture was prepared for the formulations provided in Table 1 for the examples and example > Comparatives: polyether alcohol based on sorbitol / 48 parts by weight propylene oxide, hydroxyl number 355 mg KOH / g, Polyethylene glycol, 5 parts by weight hrrsxyl index 190 mg KOH / g, Castor oil, 15 parts by weight hydroxyl number 165 mg OH-'g, Tpchloro oprapium phosphate, 20 parts by weight Di-phenyl-1-cresi phosphate 10 parts by weight Foam stabilizer based on 2 parts by weight organ 11 icona (DABCO DC 193, Air Products), The following physical expansion agents were used for the examples and comparative examples: Expansion agent 1 (according to the invention): n-pentane 68 parts by weight isopenta to 7 parts by weight n-butane weight 10 parts by weight isobutane 5 parts by weight Expansion agent 2 (according to the invention): Cyclopentane 72 parts by weight n-butane 28 parts by weight Expansion agent 3 (according to the invention): n-pentane 70 parts , in weight isopentane 8 parts by weight n-butane 7 parts by weight isobutane 4 parts by weight propane 1 part by weight Expansion agent 4 (comparative): n-pentane 80 parts by weight isopentane parts by weight Expansion agent 5 ( compare io): Ciclspentane 100 parts in weight P In order to produce the rigid polyurethane polyurethane foams, in each case a load of 500 g of the formulations illustrated in Table 1 was repaired in a mixing vessel and 480 g of this material were transferred into a mold. of foam with lid of dimensions 230 x 210 and 200 mm, a global foam density of approximately 55 g / dm3 achieved with a compaction of approximately 10 percent. After a hardening time of one hour, the foam was removed from the mold and the fire performance was determined in accordance with DIN 4102 24 hours after production. The results of this fire test are provided in the lower part of the table and show the improved fire performance obtained by using the novel expansion agents. In effect expansion of the new mixtures of e-pansin agents is better than the expansion effect obtained from the use only of hydrocarbons that are in the liquid state at room temperature. Table 1 Table 1 Example E in the Example Example 1 2 3 4 Polio! pa is in weight 10 <; "< 300 300 10 Acura pai s in weight 1.3 1.3 1.3 1.1 Part Weight Agent 7 Expansion 1 Part Weight Agent 8 Expansion 2 Torque Agent is by Weight 7 8 Expansion 3 Bulk Weight Agent Expa in 4 Expansion Weight Part Agent 5 Weight Share Solution 2.5 2.5 2.5 2.5 potassium acetate in ethylene glycol (4214) Pentamet il- parts by weight 0.8 0.8 0.8 0.8 dieti lend mine Product parts by weight 190 390 190 390 crude MDI (content of NCO 33.! * /,) OHN mg ^ 0H / g 311.99 311.99 311.99 299.53 index of 2.53 2.53 2.53 2.63 isoc ianato Classification of B2 B2 B2 B2 _--- > m 1 to open 1 DIN 4102 Flame ura cm 12.9 33.4 13.1 33.7 Table 1 Comparative Example Comparative Example 1 2 Polio] 1 0 100 Water 1.4 1.4 Expansion agent 1 Extraction agent 2 Expansion agent 3 Expansion agent 4 8 Expansion agent 5 9 2.5 2.5 potassium acetate solution in ethylene glycol < 42 * /. ) Pentametildiet i lendiami na 0.8 0.8 Crude product MDI 190 190 (content of NCO 31.1 *) OHN 318.22 318.22 Isocyanic acid 2.48 2.48 Classification of flammable-B3 B3 lity DIN 4102 To 1 ura of flame 35 .''- 35.8

Claims (14)

1. CLAIMS 1. A process for producing a rigid foams based on isocyanates, pyretardants by the reaction of organic and / or organic modified polymers with b) at least one higher molecular weight compound having at least two reactive hydrogen atoms and, if desired c) ex-chain binders or molecular weight and / or recyclers in the presence of d) flame retardants, e) water, f) novel expansion agents and g) other auxiliaries and / or additives, comprising the use, co or blowing agents, of a mixture of at least one hydrocarbon which is in the liquid state at room temperature and has 5 CD plus carbon atoms in the molecule with at least one hydrocarbon found in Gaseous state at room temperature and having 4 or less carbon atoms in the molecule.
2. 2. A process according to claim 1, wherein the hydrocarbons which are in the liquid state at room temperature and which have 5 or more carbon atoms in the molecule are used in an amount of 0.3 to 1014 by weight, based on the total amount of foam.
3. 3. A process according to claim 1, wherein the hydrocarbons which are in the gaseous state at room temperature and which have 4 or less carbon atoms in the molecule are used in an amount of 0.1 to 3014 by weight, based on in the total amount of foam.
4. 4. A process according to claim 1, wherein the hydrocarbons which are in the liquid state at room temperature and have 5 or more carbon atoms in the molecule are cyclopentane, cyclohexane and / or meth i1-iclohexane.
5. 5. A process in accordance with rei indication 1, where the hydrocarbons that are in the liquid state at room temperature and that have 5 or more carbon atoms in the molecule are non-cyclic hydrocarbons.
6. 6. A process according to claim 5, wherein the cyclic hydrocarbons which are in the liquid state at room temperature and which have 5 or more carbon atoms in the molecule are n-pentane and / isopyranne.
7. 7. A process according to claim 5, wherein the non-cyclic hydrocarbons that are in the liquid state at room temperature and have 5 or more carbon atoms in the molecule are n-hexane and / or its isomers.
8. 8. A process in accordance with that claimed in 58 rei indication 1, where the hydrocarbons that are in liquid state at room temperature and that have 5 or more carbon atoms in the molecule are alkenes.
9. 9. A process according to claim 1, wherein the hydrocarbons which are in the liquid state at room temperature and which have 5 or more carbon atoms in the molecule are hexenes / or their isomers.
10. 10. A process according to claim 1, wherein the hydrocarbons which are in a gaseous state at room temperature and which have 4 or less carbon atoms in the molecule have 3 or 4 carbon atoms.
11. 11. A process according to claim 3, wherein the hydrocarbon which is in the gaseous state at room temperature and has 4 or less carbon atoms in the molecule is n-butane.
12. 12. A process in accordance with rei indication 1, wherein the hydrocarbon which is in the gaseous state at room temperature and which has 4 or less carbon atoms in the molecule is isobutane.
13. 13. A mixture of blowing agents for producing rigid pyretardant foams, based on isocyanate, according to claim 1, which consists of a mixture of at least one hydrocarbon which is in the liquid state at room temperature and has 5 or more carbon atoms in the molecule with? 1 minus a gaseous hydrocarbon at room temperature and having 4 or less carbon atoms in the molecule, in association with the carbon dioxide produced from water and isoc rt-to.
14. 14. The use of a rigid flame retardant foam based on isocyanate produced in accordance with that claimed in claim 1 as insulation material in the construction sector.