DE2002754B2 - Process for the production of a polyurethane foam - Google Patents

Description

In the previous production of polyurethane foam, it was common practice to react relatively quickly To use components so that the glass bubbles formed to form the foam cells were quickly enclosed. The hardening had to contribute to this high speed with an almost instantaneous steep increase in viscosity. Because the bubble formation or expansion and hardening at the same time took place, it was very difficult to control the height of a squeegee-formed foam, before it was hardened and could not be further processed. Therefore, on a large scale, they were largely Forming method used to make the height of a μ Polyurethane foams to control the object formed.

From US-PS 3046 177 and 31 81 199 is still known that unpredictable irregularities in the behavior of polyurethane foam mixtures their Make long distance transport extremely disadvantageous. If you also bring the expanding Mix on rough surfaces, like the back of a carpet, on 50, it practically expands over that entire area to the same extent, and a rough or uneven surface is formed on the obtained Foam off. Both of these patents cited teach the instant formation and shaping of the Foam.

In US-PS 31 88 296 a process is described in which rapidly reacting polyurethane-forming reactants under extremely high pressures, e.g. B. at 1050 kg / cm ² , are injected into each other, whereby air under pressure is introduced tangentially into a special system to form a turbulent flow. The air then acts as a nucleating agent for the foaming gas formed by the chemical reaction. The rate of reaction is so fast that mixing must normally be done in 0.5 to 25 seconds.

Vigorous mixing of the reactive ingredients and a catalyst is used in the process of U.S. Patent 3,046,177. In this procedure the reaction begins almost immediately in the special mixer used there, and the reacting mixture becomes immediately emptied onto a mold surface, where it is simultaneously distributed and shaped with air jets, when it is in its final stage of expansion

According to that described in US Pat. No. 3,108,976 Process is carried out either from a liquid foam precursor, e.g. B. containing an NCO groups Prepolymers, optionally with the addition of crosslinking agents and catalysts, by introducing Air at positive, normal or negative pressure, a foamed mixture is formed, which after reducing the Pressure over the mixture expands and hardens, or it becomes a foam precursor and air in the same Foamed mixture produced in this manner after reducing the pressure and expanding it with the Catalyst or crosslinker mixed and cured

The object of the invention is to provide a method for producing a polyurethane foam, that before its hardening at room temperature and normal pressure in its structure and also chemically is stable, but can still be edited Can be transported over greater distances and / or temporarily stored and then shaped and which can nevertheless be cured quickly to the non-adhesive state by applying heat.

The invention thus relates to a method for producing a polyurethane foam by reacting a non-aqueous, liquid mixture of a) an organic polyisocyanate, b) a polyhydroxyl compound, c) a surfactant and d) a metal catalyst in the presence of a pore-forming gas. The procedure is through characterized in that a mixture of components a) and b) either with trimethylsiloxy-silicate copolymers as surface-active agent c) and customary metal catalysts d) or with Organosilicone stabilizers as surface-active agent C) and nickel acetylacetonate, diacetonitrile diacetylacetonate nickel, diphenyl nitrile diacetylacetonate nickel and bis-itriphenylphosphine I-diacelylacetonate nickel as Metal catalysts d) produces which in 2600 seconds at 25 ± 0.5 ° C a viscosity of no more than about 10,000 cP and only at a temperature of at least 70 "C essentially is reactive, and in this mixture an inert gas by mechanical beating uniformly dispersed in such a way that the density is less than 45% of the

Density is the non-foamed mixture UNJ then the foam at a temperature of at least 70 ⁰ C, optionally in the deformed state cures.

The mixture used can also contain a crosslinking agent, as long as its presence does not initiate substantial polymerization at room temperature. Other additives can also be used Creation of special effects, such as colorants and filler material, can also be used as long as they do not Initiate substantial polymerization at room temperature. The liquid mixture is not aqueous; H. she does not contain water, but the water contained in the raw materials of technical purity can be tolerated.

The non-aqueous, liquid mixture is practically chemically stable and is not subject to any substantial Polymerization when the viscosity of one is the most liquid Phase-forming test mixture that only contains the niclu foamed, booked, polyurethane-forming components, surface-active center! and catalytic converters contains no more than about 10,000 cP in 2600 seconds when kept at a temperature between 24.5-25.5 "C. The materials are in dear Test mixture present in the same relative amounts as that used to form the foam Mixture.

The test mixture is assessed as follows: the components mentioned are mixed for about 1 minute and 7.5 cm ^{3 of} them are placed in a Brookfield LVT viscometer with a small, jacketed test chamber. Then they are kept at a temperature of 24.5-25.5 "C, and their viscosity is determined over the period specified above about 125 ⁰ C hardens in the non-sticky state

Polyisocyanates which can be used according to the invention are those of the general formula:

Q (NCO),

in which / is an integer of 2 or more and C ^{1 is} a substituted or unsubstituted hydrocarbon group, e.g. B. an alkylene or arylene group, or a group of the general formula

Q'-Z-Q ',

in which Q 'stands for an alkylene or arylene group andl Z is -O-, -CO-, -S-, -S-Q'-S- or -SOr radical, examples of such compounds include. Hexamethylene diisocyanate, 1,8-diisocyanato-p-menthane,

Xylylene diisocyanate,

1 -Meth3; | -2,4 ~ diisocyanatocyclohexane, the Phenylene diisocyanates, the Toluylene diisocyanate, the Chlorophenylene diisocyanates,

Diphenylmethane ^ '- diisocyanate, bo

Naphthalene-1,5-diisocyanate, Triphenylmethane-4,4 ', 4 "-triisocyanate and Isopropylbenzene ^ / i-diisocyanate. Q can also stand for a polyurethane radical with the valency /; in this case μ

Q (NCO), a product commonly known as a prepolymer. These prepolymers are formed by Implementation of a stoichiometric excess of one of the above and below illustrated polyisocyanates with an active hydrogen-containing compound, in particular the im polyhydroxy-containing materials or polyols described below. Usually the polyisocyanate used in a 30 to 200% stoichiometric excess based on equivalents of isocyanate groups per equivalent of hydroxyl group in the polyol.

According to the invention, the dimers and trimers of diisocyanates as well as

Ethyl phosphone diisocyanate, C ₂ H ₅ P (O) (NCO) ₂ and Phenylphosphone diisocyanate,

C ₆ H ₅ P (O) (NCO) ₂

and the one in Siefken, Ann. 562 (1949), page 75 ff. described polyisocyanates are used.

The polyisocyanates mentioned below, used alone or as a mixture, are particularly suitable can be:

2,4-tolylene diisocyanate

2,6-tolylene diisocyanate,

raw Toluy lendiisocy anat,

Bis (4-isocyanatophenyl) methane,

Polyphenylmethylene polyisocyanates, by phosgenation of Aniline-formaldehyde condensation products getting produced,

Dianisidine diisocyanate, Xylylene diisocyanate, Bis (2-isocyanatoethyl) fumarate Bis (2-! SocyanatoethyI) carbonate

1,6-H exame thy lene diisocyanate,

1,4-tetramethylene diisocyanate

1,10-decamethylene diisocyanate,

Cumene-2,4-diisocyanate,

4-methoxy-13-phenylene diisocyanate

4-chloro-13-phenylene diisocyanate

4-bromo-13-phenylene diisocyanate,

4-ethoxy-1,3-phenylene diisocyanate.

2,4'-diisocyanatodiphenyl ether,

S. e-dimethyl-1-4 phenylene diisocyanate

2,4-dimethyl-13-phenylene diisocyanate

4,4'-diisocyanatodiphenyl ether,

Bis-S.e-p-isocyanatoäthylJ-bicyclo- [2.2.1] -hept-2-en,

Benzidine diisocyanate,

4,6-dimethyl-1,3-phenylene diisocyanate

9,10-anthracene diisocyanate,

4,4 'diisocyanatodibenzyl,

JJ-DimethyM ^ '- diisocyanatodiphenylmethane,

2,6-dimethyl-4,4'-diisocyanatodiphenyl,

2,4-diisocyanatostilbene,

33'-dimethyl-4-4'-diisocyanatodiphenyl,

33'-dimethoxy-4,4'-diisocyanatodiphenyl,

1,4-anthracene diisocyanate

23-fluoro diisocyanate,

1,8-naphthalene diisocyanate,

2,6-diisocyanatobenzofuran and

2,4,6-toluene triisocyanate.

In general, the aromatic polyisocyanates are preferred because of their greater reactivity

Furthermore, those polyisocyanates can also be used in which the isocyanate groups of polyisocyanates listed above with a monofunctional organic compound, e.g. B. a

Phenol, see Ann, Vol 562 (1949), pages 205-229, Reinhold Plastics Applications Series on Polyurethanes by BA Dombrow (published by Reinhold Publishing Corp. New York, 1957) and Saunders & Frisch, Polyurethanes: Chemistry and tech nology ^r i, Part 1, Chemistry, pages 118-121 (published by Interscience Publishers, 1962). The blocked polyisocyanates allow the more reactive polyisocyanates to be used. Their use can also be used to regulate the setting of the polymerization or curing temperature of the foam. One or more isocyanate groups in the polyisocyanate molecule can be blocked to provide the desired level of reactivity. Furthermore, the catalysts described in US Pat. No. 2,886,555 can be used in order to set the cleavage or delaminating temperature to the desired value.

The amount of polyisocyanate used varies somewhat depending on the kind of the one to be prepared Polyurethane foam. In general, the equivalent ratio of NCO groups to the total should be active hydrogen groups in the range from 0.8: 1 to 2.0: 1, preferably in the range from 1.0: 1 to 1.5: 1, lie.

Polyhydrocarbons are also used as polyhydroxy compounds for the process according to the invention terminal hydroxyl groups (cf. US Pat. No. 2,877,212), polyformals with terminal hydroxyl groups (cf. US-PS 28 70 097), fatty acid triglycerides (see. US-PS jo

28 33 730 and 27 87 601), polyester with terminal ends Hydroxyl groups (see US Pat. No. 26 98 838, 29 21 915, 25 91884, 28 66 762, 28 50 476, 26 02 783, 27 29 618, 27 79 689, 28 11 493 and 26 21 166), perfluoromethylene with terminal hydroxymethyl groups (see. US-PS

29 11 390 and 29 02 473), polyalkylene ether glycols (cf. US-PS 28 08 391 and GB-PS 7 33 624), polyalkylene arylene ether glycols (see. US-PS 28 08 391) and polyalkylene ether triols (see. US-PS 28 66 774) are suitable.

Particularly preferred polyhydroxyl compounds are polyether polyols obtained by the addition of alkylene oxides, such as ethylene oxide, propylene oxide and their Mixtures of water or polyvalent organic compounds, such as

Ethylene glycol, propylene glycol ¹ , Trimethylene glycol, 1,2-butylene glycol, I3-butanediol, 1,4-butanediol,

1,5-pentanediol, 1,2-hexanediol,

1,10-decanediol, 1,2-cyclohexanediol,

2-butene-1,4-diol, 3-cyclohexene-1,1-dimethanol,

4-methyl-3-cyclohexene-l, 1 -dimethanol,

3-methyl-1,5-pentanediol,

Diethylene glycol,

(2-hydroxyethoxy) -l-propanoI, 4- (2-hydroxyethoxy) -l-butanol,

5- (2-hydroxypropoxy) -1 -pentanol,

1 - (2 • hydroxymethoxy) -2-hexano'i,

1 - (2-hydroxypropoxy) -2-octanol,

3-allyloxy-l3-pentandio !, 2-allyloxymethyl-2 * methyl-1,3-propanediol,

3- (o-propenylphenoxy) -1, 2-propanediol,

2,2'-Diisopropylidene-bis (p-phenyleneoxy) -diethanol,

Glycerin, 5,2,6 hexanetriol, µ

1,1,1-trimethylolathane,

1,1,1 -trimethylolpropane,

3- (2-hydroxyethoxy) -1,2-propanediol,

3- (2-hydroxypropoxy) -1, 2-propanediol,

2,4-dimethyl-2- (2-hydroxyethoxy) -methylpentanediol-1,5,

l, l, l-Tris - [(2-hydroxyethoxy) methyl] ethane,

1,1,1 -Tris- [2-hydroxypropoxy) methyl] propane,

Diethylene glycol, dipropylene glycol, Pentaerythritol, sorbitol, cane sugar, Lactose, «-methyl glucoside, Ä-hydroxyalkyl glucoside, Novolak resins, phosphoric acid, Tribenzenephosphoric acid and Polyphosphoric acids such as Tripolyphosphoric acid and Tetrapolyphosphoric acid,

getting produced. The alkylene oxides used in the manufacture of polyoxyalkylene polyols normally have 2 to 4 carbon atoms. Preferred propylene oxide and mixtures of propylene oxide with ethylene oxide are used.

A preferred class of polyether polyols used in accordance with the present invention can be represented by the following general formula are shown

R [(OC _n H _2n ) _: OH] "

Herein, R denotes hydrogen when a = 1, or an a-valent hydrocarbon radical when a denotes an integer from 2 to 8, π is in each case an integer from 2 to 4, preferably 3, and each ζ is an integer with a value from 2 to 200, preferably from 15 to 100.

Further suitable polyhydroxyl compounds are the polymers obtained from cyclic esters with a reduced viscosity of at least 0.15, preferably from 0.2 to 15 and more, measured at a concentration of 0.2 g of polymer in 100 cm ^{3 of} solvent, e.g. B. cyclohexanone, benzene, chloroform or toluene, at 30 ^° C. The preferred polymers have a reduced viscosity of 03 to 10. These polymers are homopolymers or copolymers, which units of the general formula

in which each R is individually hydrogen, an alkyl radical, a halogen atom or an alkoxy radical, A Sau Ji substance, χ is an integer from 1 to 4 and y is an integer from Ibis 4, ζ is 0 or 1 and the sum of x + yi-z is at least 4 and not greater than 6, and the total number of groups R which do not share hydrogen is not more than 3, preferably not more than 2. The radicals R include e.g. B the methyl, ethyl, isopropyl, η-butyl, sec-butyl, tert-butyl and hexyl groups, chlorine, bromine and iodine, as well as methoxy, ethoxy, n-butoxy, n- Hexoxy, 2-ethylhexoxy and dodecoxy groups. Preferably, each R is a hydrogen, a lower alkyl, e.g. methyl, ethyl, n-propyl, isobutyl, and / or a lower alkoxy, e.g. B. methoxy, ethoxy, propoxy or n-butoxy group. Furthermore, the total number of carbon atoms in the substituents R is preferably not less than 8.

ί ^R ' - (A), - f R \ O
Il ο— JC - C- Il
—C- ^ ^R R.

Also suitable as polyhydroxy compounds are those polymers which contain both the repeating Structural unit of the general formula (I) and such units of the general formula

(ID

contain. Each R 'is individually hydrogen, an alkyl, cycloalkyl, aryl or chloroalkyl radical, or the two variables R 'together with the ethylene part of the oxyethylene chain of unit (II) form one

Monomers in a polyol (cf. GB-PS 10 63 222 and US-PS 33 83 35l). Suitable monomers for producing the polymer / polyols include acrylonitrile, vinyl chloride, styrene, butadiene, vinylidene chloride and the ethylenically unsaturated monomers listed in the aforementioned patents. Suitable polyols are both those listed above and those mentioned in the GB-PS and US-PS. The polymer / polyols can contain between 1 to 70% by weight, preferably 5 to 50% by weight and in particular 10 to 40% by weight, of monomer polymerized in the polyol. They are conveniently prepared by polymerizing the monomers in the selected polyol at a temperature from 40 to 150 ⁰ C in the presence of a free radical polymerization catalyst such as peroxides, persulfates, percarbonates, perborates and azo compounds. The polymer obtained /

ι ^ ιιυαιιμι

im / iiiciitviisui ^ hji

TVIIIIUIIILII

having 4 to 8 carbon atoms, preferably 5 to 6 carbon atoms; w is an integer from I to 10. It is preferred that the repeating unit (I I) contain 2 to 12 carbon atoms. Examples of R 'are the methyl, ethyl, n-propyl, isopropyl, tert-butyl ·. Hexyl, dodecyl, 2-chloroethyI, phenyl, phenethyl, Ethylphenyl, cyclopentyl, cyclohexyl and cycloheptyl radical. R 'is preferably hydrogen, a lower alkyl, e.g. methyl, ethyl, n-propyl or isopropyl. or a chloroalkyl, e.g. B. 2-chloroethyl radical.

The repeating unit (I) is represented by the oxy group (-O-) of a unit with the carbonyl group

connected to a second unit; i.e. the bond is not made by direct bonding of two carbonyl groups,

O O C C

According to the invention, polymers obtained from cyclic esters have an average Molecular weight from 500 to 2000 preferred.

The manufacture the. ^{c <} : r polymers is z. B. in the ίο US-PS 30 21 309 to 30 21 317, 31 69 945 and 29 62 524 described.

Cyclic ester / alkylene oxide copolymers with structural units (I) and (II) can be prepared by reacting a mixture of cyclic ester and alkylene oxide monomers, a surface-active agent such as a solid, relatively high molecular weight polyvinyl stearate or lauryl methacrylate / vinyl chloride copolymer (reduced viscosity in cyclohexanone at 30 ° C = 03 to 1.0), in f) the presence of an inert normally-liquid saturated aliphatic hydrocarbon such as heptane and phosphorus pentafluoride as a catalyst at elevated temperature, for. example, at about 80 ⁰ C for a period sufficient for the formation of these copolymers b5

As further polyhydroxy compounds suitable according to the invention are polymer / polyols that are obtained "by polymerization of ethylenically unsaturated Mixture of free polyol, free polymer and graft polymer / polyol complexes. The polymer / polyols are suitable for the production of polyurethane foams with a relatively high load capacity.

According to the invention, mixtures of polyether polyols, mixtures of polymer / polyols, dipropylene glycol and a cyclist i: cn ester polymer, mixtures of Polyether polyol, dipropylene glycol and polymer / polyol as well as mixtures of polyether polyol and dipropylene glycol can be used.

The polyol or polyol mixture used in the present invention can be used over a wide range have varying hydroxyl numbers. In general, the hydroxyl numbers of the polyols or their Mixtures between 28 to 1000, preferably between 100 to 800, are.

What polyo! or which particular polyol blend is used depends on the end use of the polyurethane foam. Molecular weight and hydroxyl number are selected accordingly, that flexible, semi-flexible or rigid foams are obtained. Including the polyol or polyol blend the optionally used crosslinking agent preferably has a hydroxyl number of 200 to 1000, if hard foams are to be produced, for for semi-flexible foams it is 50 to 250, and for flexible foams 45 to 70.

In order to stabilize the foam in the method according to the invention, two different requirements are to be adhered to Conditions relating to the combination of surfactant c) and metal catalyst d) required. One condition is that a trimethylsiloxy-silicate copolymer is used as the surface-active agent to be used in combination with a conventional metal catalyst. A preferred one The stabilizer is a copolymer of essentially SiOr (SiIicat) units. and (CHj ^ SiOoj- (trimethylsiloxy) units from 0.8: 1 to 2.2: 1, preferably from 1: 1 to 2.0: 1. These trimethylsiloxy silicate mixed polymers and processes for their production are described in BE-PS 7 20 212. A There is a surprising advantage in using these trimethylsiloxy-silicate copolymers their ability to increase the catalytic effectiveness of commonly used metal catalysts, such as dibutycin dilaurate, to retard synergistically at room temperature, while at the same time having an accelerating effect during curing at elevated temperatures

allow. This is particularly important since it is possible according to the invention to use catalysts which would normally be too active to allow lathering without substantial curing at room temperatures to allow. The usual metal catalysts are used in the usual concentrations. These Catalysts include both inorganic metal compounds and metal compounds with organic ones Groups. Organic tin compounds are particularly suitable. The metal catalysts can each can be used alone or in admixture. Organic tin compounds include stannous acylates. like the dialkyltin salts of carboxylic acids. Other useful but less preferred latent metal catalysts are the metal diorganodithiocarbamates. in which the organic groups, e.g. B. alkyl groups with up to / u 18 carbon atoms, preferably with 1 to 8 carbon atoms.

The second condition requires the use of nickel acetylacetonate, diacetonitrile diacetylacetonate nickel, Diphenylnitrildiacetylacetonatonicke! and bis (triphenylphosphine-diacetvlacetonatonickel as metal catalyst d) in combination with organosilicone stabilizers as surfactant c). Some of the surface-active organosilicone stabilizers are crosslinked Siloxane-polyoxyalkylene block mixture polymers in which the siloxane blocks and polyoxyalkylenes blocks by silicon-carbon or silicon-Sauprsioff-carbon conditions are connected, and mixtures thereof are suitable. The siloxane blocks consist of hydrocarbon siloxane groups and have combined an average of at least two valences of silicon per block with these conditions. At least a portion of the polyoxyalkylene blocks consists of oxylalkylene groups and is polyvalent; H. there are at least two valences of carbon and / or carbon-bonded oxygen per block with these Ties combined. Any remaining polyoxyalkylene blocks consist of oxyalkylene groups and are monovalent, i.e. H. they only have one valence carbon or carbon-bonded oxygen per block combined in these terms. Furthermore, the usual organopolysiloxane-polyoxyalkylene block copolymers, z. B. those in U.S. Patents 2,834,748, 2,846,458, 2,868,824, 2917,480 and 3,057,901 described, are used; however, they are less preferred than those equally suitable and in Combination with the usual metal catalysts used trimethylsiloxy-silicate copolymers and the partially crosslinked copolymers. The partially crosslinked copolymers and the trimethylsiloxy-silicate mixed polymers are expediently used when monomeric polyisocyanates such. B. toluene diisocyanate, for foam production is used.

The amount of organosilicone stabilizer used in the process according to the invention can be above a vary widely, e.g. B. from 0.5 to 10 parts by weight per 100 parts by weight of the polyhydroxyl compound. It there is no measurable benefit when using the organosilicone stabilizer in amounts below 0.5 or over 10 parts by weight, based on 100 parts by weight of polyhydroxyl compound. The Orgar.osiiiconstabjüsator is preferably used in an amount of 1.0 to 6.0 parts by weight, based on 100 parts by weight of polyhydroxyl compound, used. The amount of metal catalyst used in the non-aqueous liquid mixture is preferably between 0.03 to 3.0 parts by weight per 100 parts by weight of the polyhydroxyl compound.

The non-aqueous, liquid mixture can contain other ingredients such as dyes, fillers and pigments, included to create desired effects.

Air is most conveniently used as the pore-forming agent, due to its cheapness and easy availability. If necessary, however, other gases can also be used which are at room temperature and atmospheric pressure are gaseous and against all components of the non-aqueous, liquid mixture are practically inert or not able to react. These other gases include e.g. B. nitrogen, Carbon dioxide and even fluorocarbons, which are usually gaseous at room temperature.

The inert gas is mechanically hammered into the non-aqueous, liquid mixture with the aid of a High shear device such. B. a Hobart mixer or an Oakes mixer, evenly dispersed. The gas can be incorporated under pressure, as is common in an Oakes mixer, or it can be extracted from the overlying atmosphere by beating, as in a Hobart mixer will. The mechanical impact is preferably carried out at a pressure not exceeding 7.8 to 14.7 bar. It will stresses, however, that a common readily available mixer is used and not a particular one Plant is necessary.

The one beaten into the non-aqueous, liquid mixture The amount of inert gas must be sufficient to form a foam with a density of the ambient atmospheric pressure of less than 45%, preferably less than about 35%, of the density the non-aqueous, liquid mixture before foaming. The mechanical striking is done via a few seconds in an Oakes mixer, or 3 to 30 minutes in a Hobart mixer, or as appropriate Requirement to achieve the desired foam density in the mixing device used.

The foam obtained after mechanical beating is practically chemically and structurally stable, but can easily be processed ^{at room temperature, ie at 15 to 30 ° C.} The foam consistency is very similar to the consistency of an eraser cream released by an aerosol and has a density of less than 45%, preferably less than about 35%, of the density of the non-foamed mixture.

The resulting foam is then cured at a temperature of at least 7O ⁰ C, optionally in the deformed 7ustand.

The foams so produced are useful in the manufacture of flexible to rigid molded ones Foams. The uncured foams can, for. B. deformed and then by heat forming padded panels, dashboards, sun visors or armrests for automobiles, Aircraft and ships are cured, or they can be applied to the back of carpeting, to form a foam cushion cover on textiles to create lining material for Wadding and / or applied and cured for thermal insulation.

Due to their chemical and structural stability before curing, the foams can easily be deformed by molding or squeegeeing. Since there is practically no substantial chemical expansion, i. H. Expansion due to being in the non-aqueous liquid

Il

Mixture of gas formed by chemical reaction, or expansion due to volatilization of a Liquid and practically only thermal expansion takes place during heat curing, dimensional changes are easy to foresee and to check. For these reasons it is also possible to reproduce rough and uneven surfaces, such as B. when covering rough backs of carpets to avoid. This was through use; chemically expanded foams not possible.

As can be seen from the following examples, the process according to the invention, by choosing a suitable amount and type of surface-active agent, allows a certain amount of the foamed mixture to sink into the spaces between the back of a carpet. After subsequent heat curing, this expired material not only binds the applied foam back to the carpet, but also serves to connect the cheeses on the carpet back to one another. In this case, the mixture containing the enveloped gas is applied to the back of a carpet material in which the fibers pass through the carpet backing material and protrude over the back in a practically uniform, thick layer, and the mixture is cured ^{at a temperature of over 70 ° C.} A cured polyurethane foam of practically uniform thickness is thereby formed as an integral rear side of the carpet with simultaneous binding of the fibers within the rear side of the carpet. The usual carpet material is used, for. B. jute or polypropylene, and the fibers can mechanically by conventional means, e.g. B. sewing or needling, be anchored to the carpet backing material.

The fibers can consist of any conventional carpet raw material, e.g. B. made of cotton, rayon. Wool. Nylon. Acrylonitrile polymers and vinyl halide polymers. They can be in any suitable form, e.g. B. in the form of pile yarns that form a cut or looped pile on the front of the carpet backing material. The foam can be prepared by any suitable method, e.g. B. by squeegee coating applied. The backside coating can be of any desired thickness and e.g. B. 1.5 to 13 mm thick.

The uncured foamed mixture can be easily transported by a conveyor belt or by pipes from the place of its manufacture to the place of its use.

The following examples illustrate the process of the invention. All parts and percentages are based on weight. In the formulas given for the organosilicon stabilizers, Me for the methyl group and Bu for the butyl group.

Rpicntp] 1
- -. - _r - - -

3 mixtures A to C were prepared which contained the amounts of starting materials given in Table I in parts by weight. All blends had a viscosity below 10,000 cP. after being kept at 24.5-25.5 ⁰ C 2600 seconds and no mixture gelled when it was kept at room temperature for more than 1 hour.

The mixtures were mixed in a 4.5 liter Hobart N-50 mixer using a 10 wire broom Mechanically beaten for minutes. Each mixture formed a foam with a density below 45% of the Density of the mixture before foaming. This one did not become one by heat treatment cured adhesive flexible polyurethane foam.

The trimethylsiloxy-silicate copolymer was used in a comparative experiment in mixture C by an equal amount by weight of a surface-active copolymer with the average formula

Me, SiO [VIe ₂ SiO] -, [Me () | C, ll "Oi _: " (C _: 1I ₁ O) _2n Cl 1,, SiMeO _{] 5 ,, SiMc 1} replaced. The comparison mixture obtained gelled in 6 minutes at room temperature.

Table I.

100
0.1 6.0

100
0.2 6.0

100
0.4
6.0

26.0 26.0 26.0

Pol yol I *)

Dibutyltin diluur.nl

Trimethylsiloxy silicate mixture

polymer (50 Ge «.-" »in

Xylene) **)

Mixture of 80% by weight

2,4-toluene diisocyanate and

20% by weight of 2,6-toluene

diisocyanate

*) Glycerine propylene oxide adduki, average Molecular weight about 1000. Hydroxyl number 168. of the average formula

H ₂ C-CXCH ₆ O) - ^ H

HC

CXC ₁ H ₆ OI ^ H 0 (CH-Cu H

*) Molar ratio of SiO _r units to (CH ₃ I ₁ SiO ₁ ,, units

13 14

For D i e 1 2 stable foam with a density of less than 45%

^p that of the liquid mixture. To

In Example 1, the heating of the foam was in the mixture A to 125 ⁰ C, it cured to a

Dibutyltin dilaurate by 0.02 parts by weight stannous octoate non-sticky, pliable foam in less than

replaced. The mixture obtained had finished after 2600-10 minutes.

Seconds at 24.5-25.5 ° C a viscosity of about I _n the following examples are set forth in Table 2

900 cP. According to Example 1, a listed surface-active agent was used from the mixture.

Table 2
Surface active agents

No. Form!

1. Me ₁ SiO (Mc-SiOh- [MeO (C Ml "),", (C-II ₄ O) .- ,, -QH ₁₁ SiMcOk _n SiMc;

2. McSiOIMe-SiOI- [MeO (CMl ₁₁ O); , (C-Il ₄ OK, X ₅ 11,, SiMeOk ₁₁ SiMe,
1 Me, SiO (Me, SiO] -.- [MeO (C, H ₆ O), - i (C; H ₄ O); " _h C; H ₍ , SiMeO] ,,, SiMe-,

4. Mc ₁ SiO [Me-SiO) - ^ MeO (C ₁ H ₁₁ O) I, _(C: I, O) _4, C ₁ H ₁₁ SiMeO ^ ₁₁ SIMC!.

5. Me, Si0 [Me, Si0] - "[Bu0 (C, H ₍₁ 0) _M (C-H40) _l .,., C; H ₍ , SiMe0], ..- SiMe,

6. Mc ₁ SiO [Me-SiOWMeO (C-II ₄ O) -C ₁ H ₁₁ SiMeO] -SiMe ₁

7. Me ₁ SiO [Me-SiO] I ₁ [MeO (CH ₄ O) _1n C ₁ II ₁₁ SiMeOl ^ SiMe-,
+ Methoxytriglycol in a 50:50 mixture by weight

8. Me, Si0 [Me _: Si0] ₄₁ [Me0 (C ₁ H, 0) ₍₁ (CH ₄ 0); -, C-, II, SiMe0] ,,, SiMe ₁

9. Partially crosslinked siloxane-polyoxylakylene block copolymer and butyl monoether of polyoxypropylene glycol with a viscosity of 65 Savbolt Universal seconds at 38 C in a 50:50 mixture by weight *)

*) The siloxane block in the siloxane-polyoxyalkylene block copolymer corresponds to the average formula

Me-, SiO [Me-Si01i -. [SiMeO]; , SiMe- ,;
per siloxane block there were 1.1 mol / divalent polyoxyethylene blocks bonded to silicon - "it of the average formula

-C ₁ M ₆ O (C _- -H ₄ OX ₁ H ₆
and 4.4 mol of monovalent silicon-bonded polyoxyethylene blocks with the average formula per siloxane block

HO (CH ₁ O) -CMI ,, -.
before.

Example j

The following ingredients were made into 5 mixes, essentially a Triisocyana! exist ·, and the

σ; π A is called F JipreKtH! ¹ '■ ·· ■ has the following properties:

_{β c} - parts by weight

Polyol II *) 1000 isocyanate equivalent 133.5

Polyisocyanate 12.0 viscosity, cP at 25 C 250
Surface active agent according to Hydrolyzed «« Chlorine,% 035

Table 3 mn Specific weight, g / cm ³ at 20 ° C 1.2

κι- ι ι. "Flash point; ⁰ C 218

N.ckelacetylacetonate 0.5 NCO content. % (Minimum) 31

*) Mixture of diols and triplets, produced by Gehall an insoluble

Addition of ethylene oxide and propylene oxide in a solid none
Ratio, the average 14 wt .-% oxyethylene unit

th and 86% by weight of oxypropylene units, based on the _b0 each mixture A to E was as in Example 1 10

entire oxyalkylene units, delivered_, mechanically beaten to a mixture of minutes , with one

A ⁰ ASJA 5KS5ÄÄ2SSS! ^s _D ^ch r ^te _h T ^{c hung} _d 4 ^{der fn T} _k ^abeII r, ³ H ^ge H ^nannfe i!

about 3700th density was obtained. It was structural and chemical

"Polyisocyanate of the general formula stable for at least 60 minutes and resulted in the values in Table 3

b5 listed flow rate Each foamed

NCO INCOI NCO ^te mixture cured in less than 10 minutes

I I! 125 ° C to a non-sticky, pliable foam

C ₆ H ₁ CH ₂ -IQH, -L-CH ₂ C ₆ H ₁ .

Table 3

mixture

No. of surfactant according to table 2

Density of the foamed drainage speed; Mischuni; cm ^{3 expired before} curing per 100 cm ³

foamed uncured

Mix in

g / cm ³ 30 min.

60 min.

A. B. C. D. E.

3 4th 5 6th 8th

0.420 0.610 0.303 0.364 0.434 0 0 0 0 0

2 10

1 10

Example 4 Hydroxyl number about 48, with the average formula

A mixture was made from the following ingredients:

Polyol I from Example 1 toluylene diisocyanate nickel acetylacetonate trimethylsiloxy silicate copolymer 50% by weight in xylene (molar ratio of SiO ₂ units to (CH ₃ ) 3SiOo3 units 2: 1)

Parts by weight 100.0 26.0 03

6.0

HCO (QH ₆ OWC ₁ H ₄ OV ₂ H H ₂ CO (C ₃ H ₆ OW (C ₁ H ₄ OU _-2 H

**) Mixture with an average hydroxyl number of about 785, the about 133 parts of ethylene glycol and about 863 parts of an Ethyloxidadducttriols with an average _{] S} molecular weight of about 7.69 and the average

formula

H ₂ CO (C ₂ H ₄ O) ₁ JH HCO (C ₂ H ₄ O) ₁ JH H ₂ CO (C ₂ H ₄ O) ₁ JH

The viscosity of the mixture was about 450 cP after 2600 seconds at 24.5-25.5 ° C.

The mixture was foamed as in Example 1 by beating for 10 minutes. The foam obtained had a density of about 0.16 g / cm ³ and was applied to a substrate in a thickness of 6 mm

applied. The coated substrate was 5 minutes,. _{B. r} ", _MJ1 . "^

Cured at 25 "C. A non-45 cyanate of Example 1 and 16 parts by weight of a polyol of the adhesive, uniform foam with a mean average cell size formula and a density of about 0.125 g / cm ^{3 were formed} .

contains * · *) Reaction product of 84 parts by weight of toluene diiso-

Example 5

This example shows the range of foam densities and running speeds that can be achieved by the method according to the invention.

Mixtures A to} were prepared from the following ingredients;

Parts by weight Polyol Hl) 95.0 Polyol IV ··) 5.0 NCO prepolymer ···) 20.6 Surfactant according to Table 4 10.0 Nickel acetylacetonate 05

60

*) Ethylene oxide / propylene oxide adduct with glycerine, average molecular weight about 3525, average H ₁ C

HC - _{O (C 1} H ₆ O) ₁₉ H H ₁ CO (CH ₆ O) ₂₉ H

with an average molecular weight of about 259 and an OH number of about 650, which is 323% by weight free NCO groups included

The viscosity of each resultant mixture was after 2600 seconds at 24.5-25.5 C ^s well under 10,000 cP.

Each mixture A to J was mechanically beaten for 10 minutes as in Example I, a foamed mixture with the density stated in Table 4 being obtained. Each foam was structurally and chemically stable for at least 50 minutes and was cured in less than 10 minutes at 125 ^C C to a non-tacky, semi-flexible foam with the density given in Table 4

909 534/42

Table 4

17 18

Mixture No. of surface foam density; g / cm ^{3 run-off} speed;

active agent expired cm ^J per 100 cm

according to table 2 before hardening after hardening foamed non-hardened

Mix in

30 min. 60 min.

A 1 0.515 0.386 0 1

B 2 0.303 0.280 0 0

C 3 0.413 0.341 0 0

D 4 0.552 0.455 0 0.5

E 5 0.290 0.279 0 0

F 6 0.276 0.233 0 0

G 7 0.292 0.268 0 2

H 8 0.293 0.271 0 0

I 9 0.242 0.232 0 0

J I *) 0.476 0.320 ö i

*) Trimethylsiluxy-silicate copolymer (molar ratio SiO ₂ units to (CHj) 3 SiO _0, 5 units 2: 1), SO wt .-% in Polyol I of Example 1. Fig.

Claims (4)

Patent claims: 1. A method for producing a polyurethane foam by implementing a non-aqueous gen, liquid mixture a) an organic polyisocyanate, b) a polyhydroxyl compound, c) a surfactant and d) a metal catalyst ι υ in the presence of a pore-forming gas, characterized in that one Mixture of components a) and b) either with trimethylsiloxy-silicate copolymers as surface-active agent c) and customary Metallka- ι> catalysts d) or with organosilicone stabilizers as surface-active agents c) and nickel acetylacetonate, diacetonitrile diacetylacetonate nickel, diphenyl nitrile diacetylacetonaton nickel and bis (triphenylpnosphine) diacetyla- cetonatonickel produced as Meiallkaiaiysatoren d), soft in 2600 seconds at 25 ± 0.5 ⁰ C a viscosity of not more than about 10000 cPs and which is only ^{essentially reactive at a temperature of at least 70 0} C, and in this mixture an inert gas is evenly dispersed by mechanical beating in such a way that the density is less than 45% of the density of the non-foamed mixture, and then the foam cures at a temperature of at least 70 ° C., optionally in the deformed state 2. The method according to claim 1, characterized in that organic tin compounds are used as the usual metal catalysts a 3. The method according to claim 1 and 2, characterized in that the inert gas is air used 4. Use of the method according to claims 1 to 3 for the production of backside coatings of carpet materials by applying the foam to the back of the carpet material and subsequent curing. 45